Google Git
Sign in
ara-mdk / platform / external / v8 / 80d68eab642096c1a48b6474d6ec33064b0ad1f5 / . / src / arm / code-stubs-arm.cc
blob: f75ee8bde8add583efd789b1ce5b2e82a7fb0451 [file] [log] [blame]
// Copyright 2010 the V8 project authors. All rights reserved.
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following
// disclaimer in the documentation and/or other materials provided
// with the distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#include "v8.h"
#if defined(V8_TARGET_ARCH_ARM)
#include "bootstrapper.h"
#include "code-stubs.h"
#include "regexp-macro-assembler.h"
namespace v8 {
namespace internal {
#define __ ACCESS_MASM(masm)
static void EmitIdenticalObjectComparison(MacroAssembler* masm,
Label* slow,
Condition cc,
bool never_nan_nan);
static void EmitSmiNonsmiComparison(MacroAssembler* masm,
Register lhs,
Register rhs,
Label* lhs_not_nan,
Label* slow,
bool strict);
static void EmitTwoNonNanDoubleComparison(MacroAssembler* masm, Condition cc);
static void EmitStrictTwoHeapObjectCompare(MacroAssembler* masm,
Register lhs,
Register rhs);
void FastNewClosureStub::Generate(MacroAssembler* masm) {
// Create a new closure from the given function info in new
// space. Set the context to the current context in cp.
Label gc;
// Pop the function info from the stack.
__ pop(r3);
// Attempt to allocate new JSFunction in new space.
__ AllocateInNewSpace(JSFunction::kSize,
r0,
r1,
r2,
&gc,
TAG_OBJECT);
// Compute the function map in the current global context and set that
// as the map of the allocated object.
__ ldr(r2, MemOperand(cp, Context::SlotOffset(Context::GLOBAL_INDEX)));
__ ldr(r2, FieldMemOperand(r2, GlobalObject::kGlobalContextOffset));
__ ldr(r2, MemOperand(r2, Context::SlotOffset(Context::FUNCTION_MAP_INDEX)));
__ str(r2, FieldMemOperand(r0, HeapObject::kMapOffset));
// Initialize the rest of the function. We don't have to update the
// write barrier because the allocated object is in new space.
__ LoadRoot(r1, Heap::kEmptyFixedArrayRootIndex);
__ LoadRoot(r2, Heap::kTheHoleValueRootIndex);
__ str(r1, FieldMemOperand(r0, JSObject::kPropertiesOffset));
__ str(r1, FieldMemOperand(r0, JSObject::kElementsOffset));
__ str(r2, FieldMemOperand(r0, JSFunction::kPrototypeOrInitialMapOffset));
__ str(r3, FieldMemOperand(r0, JSFunction::kSharedFunctionInfoOffset));
__ str(cp, FieldMemOperand(r0, JSFunction::kContextOffset));
__ str(r1, FieldMemOperand(r0, JSFunction::kLiteralsOffset));
// Initialize the code pointer in the function to be the one
// found in the shared function info object.
__ ldr(r3, FieldMemOperand(r3, SharedFunctionInfo::kCodeOffset));
__ add(r3, r3, Operand(Code::kHeaderSize - kHeapObjectTag));
__ str(r3, FieldMemOperand(r0, JSFunction::kCodeEntryOffset));
// Return result. The argument function info has been popped already.
__ Ret();
// Create a new closure through the slower runtime call.
__ bind(&gc);
__ Push(cp, r3);
__ TailCallRuntime(Runtime::kNewClosure, 2, 1);
}
void FastNewContextStub::Generate(MacroAssembler* masm) {
// Try to allocate the context in new space.
Label gc;
int length = slots_ + Context::MIN_CONTEXT_SLOTS;
// Attempt to allocate the context in new space.
__ AllocateInNewSpace(FixedArray::SizeFor(length),
r0,
r1,
r2,
&gc,
TAG_OBJECT);
// Load the function from the stack.
__ ldr(r3, MemOperand(sp, 0));
// Setup the object header.
__ LoadRoot(r2, Heap::kContextMapRootIndex);
__ str(r2, FieldMemOperand(r0, HeapObject::kMapOffset));
__ mov(r2, Operand(Smi::FromInt(length)));
__ str(r2, FieldMemOperand(r0, FixedArray::kLengthOffset));
// Setup the fixed slots.
__ mov(r1, Operand(Smi::FromInt(0)));
__ str(r3, MemOperand(r0, Context::SlotOffset(Context::CLOSURE_INDEX)));
__ str(r0, MemOperand(r0, Context::SlotOffset(Context::FCONTEXT_INDEX)));
__ str(r1, MemOperand(r0, Context::SlotOffset(Context::PREVIOUS_INDEX)));
__ str(r1, MemOperand(r0, Context::SlotOffset(Context::EXTENSION_INDEX)));
// Copy the global object from the surrounding context.
__ ldr(r1, MemOperand(cp, Context::SlotOffset(Context::GLOBAL_INDEX)));
__ str(r1, MemOperand(r0, Context::SlotOffset(Context::GLOBAL_INDEX)));
// Initialize the rest of the slots to undefined.
__ LoadRoot(r1, Heap::kUndefinedValueRootIndex);
for (int i = Context::MIN_CONTEXT_SLOTS; i < length; i++) {
__ str(r1, MemOperand(r0, Context::SlotOffset(i)));
}
// Remove the on-stack argument and return.
__ mov(cp, r0);
__ pop();
__ Ret();
// Need to collect. Call into runtime system.
__ bind(&gc);
__ TailCallRuntime(Runtime::kNewContext, 1, 1);
}
void FastCloneShallowArrayStub::Generate(MacroAssembler* masm) {
// Stack layout on entry:
//
// [sp]: constant elements.
// [sp + kPointerSize]: literal index.
// [sp + (2 * kPointerSize)]: literals array.
// All sizes here are multiples of kPointerSize.
int elements_size = (length_ > 0) ? FixedArray::SizeFor(length_) : 0;
int size = JSArray::kSize + elements_size;
// Load boilerplate object into r3 and check if we need to create a
// boilerplate.
Label slow_case;
__ ldr(r3, MemOperand(sp, 2 * kPointerSize));
__ ldr(r0, MemOperand(sp, 1 * kPointerSize));
__ add(r3, r3, Operand(FixedArray::kHeaderSize - kHeapObjectTag));
__ ldr(r3, MemOperand(r3, r0, LSL, kPointerSizeLog2 - kSmiTagSize));
__ LoadRoot(ip, Heap::kUndefinedValueRootIndex);
__ cmp(r3, ip);
__ b(eq, &slow_case);
if (FLAG_debug_code) {
const char* message;
Heap::RootListIndex expected_map_index;
if (mode_ == CLONE_ELEMENTS) {
message = "Expected (writable) fixed array";
expected_map_index = Heap::kFixedArrayMapRootIndex;
} else {
ASSERT(mode_ == COPY_ON_WRITE_ELEMENTS);
message = "Expected copy-on-write fixed array";
expected_map_index = Heap::kFixedCOWArrayMapRootIndex;
}
__ push(r3);
__ ldr(r3, FieldMemOperand(r3, JSArray::kElementsOffset));
__ ldr(r3, FieldMemOperand(r3, HeapObject::kMapOffset));
__ LoadRoot(ip, expected_map_index);
__ cmp(r3, ip);
__ Assert(eq, message);
__ pop(r3);
}
// Allocate both the JS array and the elements array in one big
// allocation. This avoids multiple limit checks.
__ AllocateInNewSpace(size,
r0,
r1,
r2,
&slow_case,
TAG_OBJECT);
// Copy the JS array part.
for (int i = 0; i < JSArray::kSize; i += kPointerSize) {
if ((i != JSArray::kElementsOffset) || (length_ == 0)) {
__ ldr(r1, FieldMemOperand(r3, i));
__ str(r1, FieldMemOperand(r0, i));
}
}
if (length_ > 0) {
// Get hold of the elements array of the boilerplate and setup the
// elements pointer in the resulting object.
__ ldr(r3, FieldMemOperand(r3, JSArray::kElementsOffset));
__ add(r2, r0, Operand(JSArray::kSize));
__ str(r2, FieldMemOperand(r0, JSArray::kElementsOffset));
// Copy the elements array.
__ CopyFields(r2, r3, r1.bit(), elements_size / kPointerSize);
}
// Return and remove the on-stack parameters.
__ add(sp, sp, Operand(3 * kPointerSize));
__ Ret();
__ bind(&slow_case);
__ TailCallRuntime(Runtime::kCreateArrayLiteralShallow, 3, 1);
}
// Takes a Smi and converts to an IEEE 64 bit floating point value in two
// registers. The format is 1 sign bit, 11 exponent bits (biased 1023) and
// 52 fraction bits (20 in the first word, 32 in the second). Zeros is a
// scratch register. Destroys the source register. No GC occurs during this
// stub so you don't have to set up the frame.
class ConvertToDoubleStub : public CodeStub {
public:
ConvertToDoubleStub(Register result_reg_1,
Register result_reg_2,
Register source_reg,
Register scratch_reg)
: result1_(result_reg_1),
result2_(result_reg_2),
source_(source_reg),
zeros_(scratch_reg) { }
private:
Register result1_;
Register result2_;
Register source_;
Register zeros_;
// Minor key encoding in 16 bits.
class ModeBits: public BitField<OverwriteMode, 0, 2> {};
class OpBits: public BitField<Token::Value, 2, 14> {};
Major MajorKey() { return ConvertToDouble; }
int MinorKey() {
// Encode the parameters in a unique 16 bit value.
return result1_.code() +
(result2_.code() << 4) +
(source_.code() << 8) +
(zeros_.code() << 12);
}
void Generate(MacroAssembler* masm);
const char* GetName() { return "ConvertToDoubleStub"; }
#ifdef DEBUG
void Print() { PrintF("ConvertToDoubleStub\n"); }
#endif
};
void ConvertToDoubleStub::Generate(MacroAssembler* masm) {
#ifndef BIG_ENDIAN_FLOATING_POINT
Register exponent = result1_;
Register mantissa = result2_;
#else
Register exponent = result2_;
Register mantissa = result1_;
#endif
Label not_special;
// Convert from Smi to integer.
__ mov(source_, Operand(source_, ASR, kSmiTagSize));
// Move sign bit from source to destination. This works because the sign bit
// in the exponent word of the double has the same position and polarity as
// the 2's complement sign bit in a Smi.
STATIC_ASSERT(HeapNumber::kSignMask == 0x80000000u);
__ and_(exponent, source_, Operand(HeapNumber::kSignMask), SetCC);
// Subtract from 0 if source was negative.
__ rsb(source_, source_, Operand(0), LeaveCC, ne);
// We have -1, 0 or 1, which we treat specially. Register source_ contains
// absolute value: it is either equal to 1 (special case of -1 and 1),
// greater than 1 (not a special case) or less than 1 (special case of 0).
__ cmp(source_, Operand(1));
__ b(gt, &not_special);
// For 1 or -1 we need to or in the 0 exponent (biased to 1023).
static const uint32_t exponent_word_for_1 =
HeapNumber::kExponentBias << HeapNumber::kExponentShift;
__ orr(exponent, exponent, Operand(exponent_word_for_1), LeaveCC, eq);
// 1, 0 and -1 all have 0 for the second word.
__ mov(mantissa, Operand(0));
__ Ret();
__ bind(&not_special);
// Count leading zeros. Uses mantissa for a scratch register on pre-ARM5.
// Gets the wrong answer for 0, but we already checked for that case above.
__ CountLeadingZeros(zeros_, source_, mantissa);
// Compute exponent and or it into the exponent register.
// We use mantissa as a scratch register here. Use a fudge factor to
// divide the constant 31 + HeapNumber::kExponentBias, 0x41d, into two parts
// that fit in the ARM's constant field.
int fudge = 0x400;
__ rsb(mantissa, zeros_, Operand(31 + HeapNumber::kExponentBias - fudge));
__ add(mantissa, mantissa, Operand(fudge));
__ orr(exponent,
exponent,
Operand(mantissa, LSL, HeapNumber::kExponentShift));
// Shift up the source chopping the top bit off.
__ add(zeros_, zeros_, Operand(1));
// This wouldn't work for 1.0 or -1.0 as the shift would be 32 which means 0.
__ mov(source_, Operand(source_, LSL, zeros_));
// Compute lower part of fraction (last 12 bits).
__ mov(mantissa, Operand(source_, LSL, HeapNumber::kMantissaBitsInTopWord));
// And the top (top 20 bits).
__ orr(exponent,
exponent,
Operand(source_, LSR, 32 - HeapNumber::kMantissaBitsInTopWord));
__ Ret();
}
// See comment for class.
void WriteInt32ToHeapNumberStub::Generate(MacroAssembler* masm) {
Label max_negative_int;
// the_int_ has the answer which is a signed int32 but not a Smi.
// We test for the special value that has a different exponent. This test
// has the neat side effect of setting the flags according to the sign.
STATIC_ASSERT(HeapNumber::kSignMask == 0x80000000u);
__ cmp(the_int_, Operand(0x80000000u));
__ b(eq, &max_negative_int);
// Set up the correct exponent in scratch_. All non-Smi int32s have the same.
// A non-Smi integer is 1.xxx * 2^30 so the exponent is 30 (biased).
uint32_t non_smi_exponent =
(HeapNumber::kExponentBias + 30) << HeapNumber::kExponentShift;
__ mov(scratch_, Operand(non_smi_exponent));
// Set the sign bit in scratch_ if the value was negative.
__ orr(scratch_, scratch_, Operand(HeapNumber::kSignMask), LeaveCC, cs);
// Subtract from 0 if the value was negative.
__ rsb(the_int_, the_int_, Operand(0), LeaveCC, cs);
// We should be masking the implict first digit of the mantissa away here,
// but it just ends up combining harmlessly with the last digit of the
// exponent that happens to be 1. The sign bit is 0 so we shift 10 to get
// the most significant 1 to hit the last bit of the 12 bit sign and exponent.
ASSERT(((1 << HeapNumber::kExponentShift) & non_smi_exponent) != 0);
const int shift_distance = HeapNumber::kNonMantissaBitsInTopWord - 2;
__ orr(scratch_, scratch_, Operand(the_int_, LSR, shift_distance));
__ str(scratch_, FieldMemOperand(the_heap_number_,
HeapNumber::kExponentOffset));
__ mov(scratch_, Operand(the_int_, LSL, 32 - shift_distance));
__ str(scratch_, FieldMemOperand(the_heap_number_,
HeapNumber::kMantissaOffset));
__ Ret();
__ bind(&max_negative_int);
// The max negative int32 is stored as a positive number in the mantissa of
// a double because it uses a sign bit instead of using two's complement.
// The actual mantissa bits stored are all 0 because the implicit most
// significant 1 bit is not stored.
non_smi_exponent += 1 << HeapNumber::kExponentShift;
__ mov(ip, Operand(HeapNumber::kSignMask | non_smi_exponent));
__ str(ip, FieldMemOperand(the_heap_number_, HeapNumber::kExponentOffset));
__ mov(ip, Operand(0));
__ str(ip, FieldMemOperand(the_heap_number_, HeapNumber::kMantissaOffset));
__ Ret();
}
// Handle the case where the lhs and rhs are the same object.
// Equality is almost reflexive (everything but NaN), so this is a test
// for "identity and not NaN".
static void EmitIdenticalObjectComparison(MacroAssembler* masm,
Label* slow,
Condition cc,
bool never_nan_nan) {
Label not_identical;
Label heap_number, return_equal;
__ cmp(r0, r1);
__ b(ne, &not_identical);
// The two objects are identical. If we know that one of them isn't NaN then
// we now know they test equal.
if (cc != eq || !never_nan_nan) {
// Test for NaN. Sadly, we can't just compare to Factory::nan_value(),
// so we do the second best thing - test it ourselves.
// They are both equal and they are not both Smis so both of them are not
// Smis. If it's not a heap number, then return equal.
if (cc == lt || cc == gt) {
__ CompareObjectType(r0, r4, r4, FIRST_JS_OBJECT_TYPE);
__ b(ge, slow);
} else {
__ CompareObjectType(r0, r4, r4, HEAP_NUMBER_TYPE);
__ b(eq, &heap_number);
// Comparing JS objects with <=, >= is complicated.
if (cc != eq) {
__ cmp(r4, Operand(FIRST_JS_OBJECT_TYPE));
__ b(ge, slow);
// Normally here we fall through to return_equal, but undefined is
// special: (undefined == undefined) == true, but
// (undefined <= undefined) == false! See ECMAScript 11.8.5.
if (cc == le || cc == ge) {
__ cmp(r4, Operand(ODDBALL_TYPE));
__ b(ne, &return_equal);
__ LoadRoot(r2, Heap::kUndefinedValueRootIndex);
__ cmp(r0, r2);
__ b(ne, &return_equal);
if (cc == le) {
// undefined <= undefined should fail.
__ mov(r0, Operand(GREATER));
} else {
// undefined >= undefined should fail.
__ mov(r0, Operand(LESS));
}
__ Ret();
}
}
}
}
__ bind(&return_equal);
if (cc == lt) {
__ mov(r0, Operand(GREATER)); // Things aren't less than themselves.
} else if (cc == gt) {
__ mov(r0, Operand(LESS)); // Things aren't greater than themselves.
} else {
__ mov(r0, Operand(EQUAL)); // Things are <=, >=, ==, === themselves.
}
__ Ret();
if (cc != eq || !never_nan_nan) {
// For less and greater we don't have to check for NaN since the result of
// x < x is false regardless. For the others here is some code to check
// for NaN.
if (cc != lt && cc != gt) {
__ bind(&heap_number);
// It is a heap number, so return non-equal if it's NaN and equal if it's
// not NaN.
// The representation of NaN values has all exponent bits (52..62) set,
// and not all mantissa bits (0..51) clear.
// Read top bits of double representation (second word of value).
__ ldr(r2, FieldMemOperand(r0, HeapNumber::kExponentOffset));
// Test that exponent bits are all set.
__ Sbfx(r3, r2, HeapNumber::kExponentShift, HeapNumber::kExponentBits);
// NaNs have all-one exponents so they sign extend to -1.
__ cmp(r3, Operand(-1));
__ b(ne, &return_equal);
// Shift out flag and all exponent bits, retaining only mantissa.
__ mov(r2, Operand(r2, LSL, HeapNumber::kNonMantissaBitsInTopWord));
// Or with all low-bits of mantissa.
__ ldr(r3, FieldMemOperand(r0, HeapNumber::kMantissaOffset));
__ orr(r0, r3, Operand(r2), SetCC);
// For equal we already have the right value in r0: Return zero (equal)
// if all bits in mantissa are zero (it's an Infinity) and non-zero if
// not (it's a NaN). For <= and >= we need to load r0 with the failing
// value if it's a NaN.
if (cc != eq) {
// All-zero means Infinity means equal.
__ Ret(eq);
if (cc == le) {
__ mov(r0, Operand(GREATER)); // NaN <= NaN should fail.
} else {
__ mov(r0, Operand(LESS)); // NaN >= NaN should fail.
}
}
__ Ret();
}
// No fall through here.
}
__ bind(&not_identical);
}
// See comment at call site.
static void EmitSmiNonsmiComparison(MacroAssembler* masm,
Register lhs,
Register rhs,
Label* lhs_not_nan,
Label* slow,
bool strict) {
ASSERT((lhs.is(r0) && rhs.is(r1)) ||
(lhs.is(r1) && rhs.is(r0)));
Label rhs_is_smi;
__ tst(rhs, Operand(kSmiTagMask));
__ b(eq, &rhs_is_smi);
// Lhs is a Smi. Check whether the rhs is a heap number.
__ CompareObjectType(rhs, r4, r4, HEAP_NUMBER_TYPE);
if (strict) {
// If rhs is not a number and lhs is a Smi then strict equality cannot
// succeed. Return non-equal
// If rhs is r0 then there is already a non zero value in it.
if (!rhs.is(r0)) {
__ mov(r0, Operand(NOT_EQUAL), LeaveCC, ne);
}
__ Ret(ne);
} else {
// Smi compared non-strictly with a non-Smi non-heap-number. Call
// the runtime.
__ b(ne, slow);
}
// Lhs is a smi, rhs is a number.
if (CpuFeatures::IsSupported(VFP3)) {
// Convert lhs to a double in d7.
CpuFeatures::Scope scope(VFP3);
__ SmiToDoubleVFPRegister(lhs, d7, r7, s15);
// Load the double from rhs, tagged HeapNumber r0, to d6.
__ sub(r7, rhs, Operand(kHeapObjectTag));
__ vldr(d6, r7, HeapNumber::kValueOffset);
} else {
__ push(lr);
// Convert lhs to a double in r2, r3.
__ mov(r7, Operand(lhs));
ConvertToDoubleStub stub1(r3, r2, r7, r6);
__ Call(stub1.GetCode(), RelocInfo::CODE_TARGET);
// Load rhs to a double in r0, r1.
__ Ldrd(r0, r1, FieldMemOperand(rhs, HeapNumber::kValueOffset));
__ pop(lr);
}
// We now have both loaded as doubles but we can skip the lhs nan check
// since it's a smi.
__ jmp(lhs_not_nan);
__ bind(&rhs_is_smi);
// Rhs is a smi. Check whether the non-smi lhs is a heap number.
__ CompareObjectType(lhs, r4, r4, HEAP_NUMBER_TYPE);
if (strict) {
// If lhs is not a number and rhs is a smi then strict equality cannot
// succeed. Return non-equal.
// If lhs is r0 then there is already a non zero value in it.
if (!lhs.is(r0)) {
__ mov(r0, Operand(NOT_EQUAL), LeaveCC, ne);
}
__ Ret(ne);
} else {
// Smi compared non-strictly with a non-smi non-heap-number. Call
// the runtime.
__ b(ne, slow);
}
// Rhs is a smi, lhs is a heap number.
if (CpuFeatures::IsSupported(VFP3)) {
CpuFeatures::Scope scope(VFP3);
// Load the double from lhs, tagged HeapNumber r1, to d7.
__ sub(r7, lhs, Operand(kHeapObjectTag));
__ vldr(d7, r7, HeapNumber::kValueOffset);
// Convert rhs to a double in d6 .
__ SmiToDoubleVFPRegister(rhs, d6, r7, s13);
} else {
__ push(lr);
// Load lhs to a double in r2, r3.
__ Ldrd(r2, r3, FieldMemOperand(lhs, HeapNumber::kValueOffset));
// Convert rhs to a double in r0, r1.
__ mov(r7, Operand(rhs));
ConvertToDoubleStub stub2(r1, r0, r7, r6);
__ Call(stub2.GetCode(), RelocInfo::CODE_TARGET);
__ pop(lr);
}
// Fall through to both_loaded_as_doubles.
}
void EmitNanCheck(MacroAssembler* masm, Label* lhs_not_nan, Condition cc) {
bool exp_first = (HeapNumber::kExponentOffset == HeapNumber::kValueOffset);
Register rhs_exponent = exp_first ? r0 : r1;
Register lhs_exponent = exp_first ? r2 : r3;
Register rhs_mantissa = exp_first ? r1 : r0;
Register lhs_mantissa = exp_first ? r3 : r2;
Label one_is_nan, neither_is_nan;
__ Sbfx(r4,
lhs_exponent,
HeapNumber::kExponentShift,
HeapNumber::kExponentBits);
// NaNs have all-one exponents so they sign extend to -1.
__ cmp(r4, Operand(-1));
__ b(ne, lhs_not_nan);
__ mov(r4,
Operand(lhs_exponent, LSL, HeapNumber::kNonMantissaBitsInTopWord),
SetCC);
__ b(ne, &one_is_nan);
__ cmp(lhs_mantissa, Operand(0));
__ b(ne, &one_is_nan);
__ bind(lhs_not_nan);
__ Sbfx(r4,
rhs_exponent,
HeapNumber::kExponentShift,
HeapNumber::kExponentBits);
// NaNs have all-one exponents so they sign extend to -1.
__ cmp(r4, Operand(-1));
__ b(ne, &neither_is_nan);
__ mov(r4,
Operand(rhs_exponent, LSL, HeapNumber::kNonMantissaBitsInTopWord),
SetCC);
__ b(ne, &one_is_nan);
__ cmp(rhs_mantissa, Operand(0));
__ b(eq, &neither_is_nan);
__ bind(&one_is_nan);
// NaN comparisons always fail.
// Load whatever we need in r0 to make the comparison fail.
if (cc == lt || cc == le) {
__ mov(r0, Operand(GREATER));
} else {
__ mov(r0, Operand(LESS));
}
__ Ret();
__ bind(&neither_is_nan);
}
// See comment at call site.
static void EmitTwoNonNanDoubleComparison(MacroAssembler* masm, Condition cc) {
bool exp_first = (HeapNumber::kExponentOffset == HeapNumber::kValueOffset);
Register rhs_exponent = exp_first ? r0 : r1;
Register lhs_exponent = exp_first ? r2 : r3;
Register rhs_mantissa = exp_first ? r1 : r0;
Register lhs_mantissa = exp_first ? r3 : r2;
// r0, r1, r2, r3 have the two doubles. Neither is a NaN.
if (cc == eq) {
// Doubles are not equal unless they have the same bit pattern.
// Exception: 0 and -0.
__ cmp(rhs_mantissa, Operand(lhs_mantissa));
__ orr(r0, rhs_mantissa, Operand(lhs_mantissa), LeaveCC, ne);
// Return non-zero if the numbers are unequal.
__ Ret(ne);
__ sub(r0, rhs_exponent, Operand(lhs_exponent), SetCC);
// If exponents are equal then return 0.
__ Ret(eq);
// Exponents are unequal. The only way we can return that the numbers
// are equal is if one is -0 and the other is 0. We already dealt
// with the case where both are -0 or both are 0.
// We start by seeing if the mantissas (that are equal) or the bottom
// 31 bits of the rhs exponent are non-zero. If so we return not
// equal.
__ orr(r4, lhs_mantissa, Operand(lhs_exponent, LSL, kSmiTagSize), SetCC);
__ mov(r0, Operand(r4), LeaveCC, ne);
__ Ret(ne);
// Now they are equal if and only if the lhs exponent is zero in its
// low 31 bits.
__ mov(r0, Operand(rhs_exponent, LSL, kSmiTagSize));
__ Ret();
} else {
// Call a native function to do a comparison between two non-NaNs.
// Call C routine that may not cause GC or other trouble.
__ push(lr);
__ PrepareCallCFunction(4, r5); // Two doubles count as 4 arguments.
__ CallCFunction(ExternalReference::compare_doubles(), 4);
__ pop(pc); // Return.
}
}
// See comment at call site.
static void EmitStrictTwoHeapObjectCompare(MacroAssembler* masm,
Register lhs,
Register rhs) {
ASSERT((lhs.is(r0) && rhs.is(r1)) ||
(lhs.is(r1) && rhs.is(r0)));
// If either operand is a JSObject or an oddball value, then they are
// not equal since their pointers are different.
// There is no test for undetectability in strict equality.
STATIC_ASSERT(LAST_TYPE == JS_FUNCTION_TYPE);
Label first_non_object;
// Get the type of the first operand into r2 and compare it with
// FIRST_JS_OBJECT_TYPE.
__ CompareObjectType(rhs, r2, r2, FIRST_JS_OBJECT_TYPE);
__ b(lt, &first_non_object);
// Return non-zero (r0 is not zero)
Label return_not_equal;
__ bind(&return_not_equal);
__ Ret();
__ bind(&first_non_object);
// Check for oddballs: true, false, null, undefined.
__ cmp(r2, Operand(ODDBALL_TYPE));
__ b(eq, &return_not_equal);
__ CompareObjectType(lhs, r3, r3, FIRST_JS_OBJECT_TYPE);
__ b(ge, &return_not_equal);
// Check for oddballs: true, false, null, undefined.
__ cmp(r3, Operand(ODDBALL_TYPE));
__ b(eq, &return_not_equal);
// Now that we have the types we might as well check for symbol-symbol.
// Ensure that no non-strings have the symbol bit set.
STATIC_ASSERT(LAST_TYPE < kNotStringTag + kIsSymbolMask);
STATIC_ASSERT(kSymbolTag != 0);
__ and_(r2, r2, Operand(r3));
__ tst(r2, Operand(kIsSymbolMask));
__ b(ne, &return_not_equal);
}
// See comment at call site.
static void EmitCheckForTwoHeapNumbers(MacroAssembler* masm,
Register lhs,
Register rhs,
Label* both_loaded_as_doubles,
Label* not_heap_numbers,
Label* slow) {
ASSERT((lhs.is(r0) && rhs.is(r1)) ||
(lhs.is(r1) && rhs.is(r0)));
__ CompareObjectType(rhs, r3, r2, HEAP_NUMBER_TYPE);
__ b(ne, not_heap_numbers);
__ ldr(r2, FieldMemOperand(lhs, HeapObject::kMapOffset));
__ cmp(r2, r3);
__ b(ne, slow); // First was a heap number, second wasn't. Go slow case.
// Both are heap numbers. Load them up then jump to the code we have
// for that.
if (CpuFeatures::IsSupported(VFP3)) {
CpuFeatures::Scope scope(VFP3);
__ sub(r7, rhs, Operand(kHeapObjectTag));
__ vldr(d6, r7, HeapNumber::kValueOffset);
__ sub(r7, lhs, Operand(kHeapObjectTag));
__ vldr(d7, r7, HeapNumber::kValueOffset);
} else {
__ Ldrd(r2, r3, FieldMemOperand(lhs, HeapNumber::kValueOffset));
__ Ldrd(r0, r1, FieldMemOperand(rhs, HeapNumber::kValueOffset));
}
__ jmp(both_loaded_as_doubles);
}
// Fast negative check for symbol-to-symbol equality.
static void EmitCheckForSymbolsOrObjects(MacroAssembler* masm,
Register lhs,
Register rhs,
Label* possible_strings,
Label* not_both_strings) {
ASSERT((lhs.is(r0) && rhs.is(r1)) ||
(lhs.is(r1) && rhs.is(r0)));
// r2 is object type of rhs.
// Ensure that no non-strings have the symbol bit set.
Label object_test;
STATIC_ASSERT(kSymbolTag != 0);
__ tst(r2, Operand(kIsNotStringMask));
__ b(ne, &object_test);
__ tst(r2, Operand(kIsSymbolMask));
__ b(eq, possible_strings);
__ CompareObjectType(lhs, r3, r3, FIRST_NONSTRING_TYPE);
__ b(ge, not_both_strings);
__ tst(r3, Operand(kIsSymbolMask));
__ b(eq, possible_strings);
// Both are symbols. We already checked they weren't the same pointer
// so they are not equal.
__ mov(r0, Operand(NOT_EQUAL));
__ Ret();
__ bind(&object_test);
__ cmp(r2, Operand(FIRST_JS_OBJECT_TYPE));
__ b(lt, not_both_strings);
__ CompareObjectType(lhs, r2, r3, FIRST_JS_OBJECT_TYPE);
__ b(lt, not_both_strings);
// If both objects are undetectable, they are equal. Otherwise, they
// are not equal, since they are different objects and an object is not
// equal to undefined.
__ ldr(r3, FieldMemOperand(rhs, HeapObject::kMapOffset));
__ ldrb(r2, FieldMemOperand(r2, Map::kBitFieldOffset));
__ ldrb(r3, FieldMemOperand(r3, Map::kBitFieldOffset));
__ and_(r0, r2, Operand(r3));
__ and_(r0, r0, Operand(1 << Map::kIsUndetectable));
__ eor(r0, r0, Operand(1 << Map::kIsUndetectable));
__ Ret();
}
void NumberToStringStub::GenerateLookupNumberStringCache(MacroAssembler* masm,
Register object,
Register result,
Register scratch1,
Register scratch2,
Register scratch3,
bool object_is_smi,
Label* not_found) {
// Use of registers. Register result is used as a temporary.
Register number_string_cache = result;
Register mask = scratch3;
// Load the number string cache.
__ LoadRoot(number_string_cache, Heap::kNumberStringCacheRootIndex);
// Make the hash mask from the length of the number string cache. It
// contains two elements (number and string) for each cache entry.
__ ldr(mask, FieldMemOperand(number_string_cache, FixedArray::kLengthOffset));
// Divide length by two (length is a smi).
__ mov(mask, Operand(mask, ASR, kSmiTagSize + 1));
__ sub(mask, mask, Operand(1)); // Make mask.
// Calculate the entry in the number string cache. The hash value in the
// number string cache for smis is just the smi value, and the hash for
// doubles is the xor of the upper and lower words. See
// Heap::GetNumberStringCache.
Label is_smi;
Label load_result_from_cache;
if (!object_is_smi) {
__ BranchOnSmi(object, &is_smi);
if (CpuFeatures::IsSupported(VFP3)) {
CpuFeatures::Scope scope(VFP3);
__ CheckMap(object,
scratch1,
Heap::kHeapNumberMapRootIndex,
not_found,
true);
STATIC_ASSERT(8 == kDoubleSize);
__ add(scratch1,
object,
Operand(HeapNumber::kValueOffset - kHeapObjectTag));
__ ldm(ia, scratch1, scratch1.bit() | scratch2.bit());
__ eor(scratch1, scratch1, Operand(scratch2));
__ and_(scratch1, scratch1, Operand(mask));
// Calculate address of entry in string cache: each entry consists
// of two pointer sized fields.
__ add(scratch1,
number_string_cache,
Operand(scratch1, LSL, kPointerSizeLog2 + 1));
Register probe = mask;
__ ldr(probe,
FieldMemOperand(scratch1, FixedArray::kHeaderSize));
__ BranchOnSmi(probe, not_found);
__ sub(scratch2, object, Operand(kHeapObjectTag));
__ vldr(d0, scratch2, HeapNumber::kValueOffset);
__ sub(probe, probe, Operand(kHeapObjectTag));
__ vldr(d1, probe, HeapNumber::kValueOffset);
__ vcmp(d0, d1);
__ vmrs(pc);
__ b(ne, not_found); // The cache did not contain this value.
__ b(&load_result_from_cache);
} else {
__ b(not_found);
}
}
__ bind(&is_smi);
Register scratch = scratch1;
__ and_(scratch, mask, Operand(object, ASR, 1));
// Calculate address of entry in string cache: each entry consists
// of two pointer sized fields.
__ add(scratch,
number_string_cache,
Operand(scratch, LSL, kPointerSizeLog2 + 1));
// Check if the entry is the smi we are looking for.
Register probe = mask;
__ ldr(probe, FieldMemOperand(scratch, FixedArray::kHeaderSize));
__ cmp(object, probe);
__ b(ne, not_found);
// Get the result from the cache.
__ bind(&load_result_from_cache);
__ ldr(result,
FieldMemOperand(scratch, FixedArray::kHeaderSize + kPointerSize));
__ IncrementCounter(&Counters::number_to_string_native,
1,
scratch1,
scratch2);
}
void NumberToStringStub::Generate(MacroAssembler* masm) {
Label runtime;
__ ldr(r1, MemOperand(sp, 0));
// Generate code to lookup number in the number string cache.
GenerateLookupNumberStringCache(masm, r1, r0, r2, r3, r4, false, &runtime);
__ add(sp, sp, Operand(1 * kPointerSize));
__ Ret();
__ bind(&runtime);
// Handle number to string in the runtime system if not found in the cache.
__ TailCallRuntime(Runtime::kNumberToStringSkipCache, 1, 1);
}
void RecordWriteStub::Generate(MacroAssembler* masm) {
__ add(offset_, object_, Operand(offset_));
__ RecordWriteHelper(object_, offset_, scratch_);
__ Ret();
}
// On entry lhs_ and rhs_ are the values to be compared.
// On exit r0 is 0, positive or negative to indicate the result of
// the comparison.
void CompareStub::Generate(MacroAssembler* masm) {
ASSERT((lhs_.is(r0) && rhs_.is(r1)) ||
(lhs_.is(r1) && rhs_.is(r0)));
Label slow; // Call builtin.
Label not_smis, both_loaded_as_doubles, lhs_not_nan;
// NOTICE! This code is only reached after a smi-fast-case check, so
// it is certain that at least one operand isn't a smi.
// Handle the case where the objects are identical. Either returns the answer
// or goes to slow. Only falls through if the objects were not identical.
EmitIdenticalObjectComparison(masm, &slow, cc_, never_nan_nan_);
// If either is a Smi (we know that not both are), then they can only
// be strictly equal if the other is a HeapNumber.
STATIC_ASSERT(kSmiTag == 0);
ASSERT_EQ(0, Smi::FromInt(0));
__ and_(r2, lhs_, Operand(rhs_));
__ tst(r2, Operand(kSmiTagMask));
__ b(ne, &not_smis);
// One operand is a smi. EmitSmiNonsmiComparison generates code that can:
// 1) Return the answer.
// 2) Go to slow.
// 3) Fall through to both_loaded_as_doubles.
// 4) Jump to lhs_not_nan.
// In cases 3 and 4 we have found out we were dealing with a number-number
// comparison. If VFP3 is supported the double values of the numbers have
// been loaded into d7 and d6. Otherwise, the double values have been loaded
// into r0, r1, r2, and r3.
EmitSmiNonsmiComparison(masm, lhs_, rhs_, &lhs_not_nan, &slow, strict_);
__ bind(&both_loaded_as_doubles);
// The arguments have been converted to doubles and stored in d6 and d7, if
// VFP3 is supported, or in r0, r1, r2, and r3.
if (CpuFeatures::IsSupported(VFP3)) {
__ bind(&lhs_not_nan);
CpuFeatures::Scope scope(VFP3);
Label no_nan;
// ARMv7 VFP3 instructions to implement double precision comparison.
__ vcmp(d7, d6);
__ vmrs(pc); // Move vector status bits to normal status bits.
Label nan;
__ b(vs, &nan);
__ mov(r0, Operand(EQUAL), LeaveCC, eq);
__ mov(r0, Operand(LESS), LeaveCC, lt);
__ mov(r0, Operand(GREATER), LeaveCC, gt);
__ Ret();
__ bind(&nan);
// If one of the sides was a NaN then the v flag is set. Load r0 with
// whatever it takes to make the comparison fail, since comparisons with NaN
// always fail.
if (cc_ == lt || cc_ == le) {
__ mov(r0, Operand(GREATER));
} else {
__ mov(r0, Operand(LESS));
}
__ Ret();
} else {
// Checks for NaN in the doubles we have loaded. Can return the answer or
// fall through if neither is a NaN. Also binds lhs_not_nan.
EmitNanCheck(masm, &lhs_not_nan, cc_);
// Compares two doubles in r0, r1, r2, r3 that are not NaNs. Returns the
// answer. Never falls through.
EmitTwoNonNanDoubleComparison(masm, cc_);
}
__ bind(&not_smis);
// At this point we know we are dealing with two different objects,
// and neither of them is a Smi. The objects are in rhs_ and lhs_.
if (strict_) {
// This returns non-equal for some object types, or falls through if it
// was not lucky.
EmitStrictTwoHeapObjectCompare(masm, lhs_, rhs_);
}
Label check_for_symbols;
Label flat_string_check;
// Check for heap-number-heap-number comparison. Can jump to slow case,
// or load both doubles into r0, r1, r2, r3 and jump to the code that handles
// that case. If the inputs are not doubles then jumps to check_for_symbols.
// In this case r2 will contain the type of rhs_. Never falls through.
EmitCheckForTwoHeapNumbers(masm,
lhs_,
rhs_,
&both_loaded_as_doubles,
&check_for_symbols,
&flat_string_check);
__ bind(&check_for_symbols);
// In the strict case the EmitStrictTwoHeapObjectCompare already took care of
// symbols.
if (cc_ == eq && !strict_) {
// Returns an answer for two symbols or two detectable objects.
// Otherwise jumps to string case or not both strings case.
// Assumes that r2 is the type of rhs_ on entry.
EmitCheckForSymbolsOrObjects(masm, lhs_, rhs_, &flat_string_check, &slow);
}
// Check for both being sequential ASCII strings, and inline if that is the
// case.
__ bind(&flat_string_check);
__ JumpIfNonSmisNotBothSequentialAsciiStrings(lhs_, rhs_, r2, r3, &slow);
__ IncrementCounter(&Counters::string_compare_native, 1, r2, r3);
StringCompareStub::GenerateCompareFlatAsciiStrings(masm,
lhs_,
rhs_,
r2,
r3,
r4,
r5);
// Never falls through to here.
__ bind(&slow);
__ Push(lhs_, rhs_);
// Figure out which native to call and setup the arguments.
Builtins::JavaScript native;
if (cc_ == eq) {
native = strict_ ? Builtins::STRICT_EQUALS : Builtins::EQUALS;
} else {
native = Builtins::COMPARE;
int ncr; // NaN compare result
if (cc_ == lt || cc_ == le) {
ncr = GREATER;
} else {
ASSERT(cc_ == gt || cc_ == ge); // remaining cases
ncr = LESS;
}
__ mov(r0, Operand(Smi::FromInt(ncr)));
__ push(r0);
}
// Call the native; it returns -1 (less), 0 (equal), or 1 (greater)
// tagged as a small integer.
__ InvokeBuiltin(native, JUMP_JS);
}
// This stub does not handle the inlined cases (Smis, Booleans, undefined).
// The stub returns zero for false, and a non-zero value for true.
void ToBooleanStub::Generate(MacroAssembler* masm) {
Label false_result;
Label not_heap_number;
Register scratch = r7;
// HeapNumber => false iff +0, -0, or NaN.
__ ldr(scratch, FieldMemOperand(tos_, HeapObject::kMapOffset));
__ LoadRoot(ip, Heap::kHeapNumberMapRootIndex);
__ cmp(scratch, ip);
__ b(&not_heap_number, ne);
__ sub(ip, tos_, Operand(kHeapObjectTag));
__ vldr(d1, ip, HeapNumber::kValueOffset);
__ vcmp(d1, 0.0);
__ vmrs(pc);
// "tos_" is a register, and contains a non zero value by default.
// Hence we only need to overwrite "tos_" with zero to return false for
// FP_ZERO or FP_NAN cases. Otherwise, by default it returns true.
__ mov(tos_, Operand(0), LeaveCC, eq); // for FP_ZERO
__ mov(tos_, Operand(0), LeaveCC, vs); // for FP_NAN
__ Ret();
__ bind(&not_heap_number);
// Check if the value is 'null'.
// 'null' => false.
__ LoadRoot(ip, Heap::kNullValueRootIndex);
__ cmp(tos_, ip);
__ b(&false_result, eq);
// It can be an undetectable object.
// Undetectable => false.
__ ldr(ip, FieldMemOperand(tos_, HeapObject::kMapOffset));
__ ldrb(scratch, FieldMemOperand(ip, Map::kBitFieldOffset));
__ and_(scratch, scratch, Operand(1 << Map::kIsUndetectable));
__ cmp(scratch, Operand(1 << Map::kIsUndetectable));
__ b(&false_result, eq);
// JavaScript object => true.
__ ldr(scratch, FieldMemOperand(tos_, HeapObject::kMapOffset));
__ ldrb(scratch, FieldMemOperand(scratch, Map::kInstanceTypeOffset));
__ cmp(scratch, Operand(FIRST_JS_OBJECT_TYPE));
// "tos_" is a register and contains a non-zero value.
// Hence we implicitly return true if the greater than
// condition is satisfied.
__ Ret(gt);
// Check for string
__ ldr(scratch, FieldMemOperand(tos_, HeapObject::kMapOffset));
__ ldrb(scratch, FieldMemOperand(scratch, Map::kInstanceTypeOffset));
__ cmp(scratch, Operand(FIRST_NONSTRING_TYPE));
// "tos_" is a register and contains a non-zero value.
// Hence we implicitly return true if the greater than
// condition is satisfied.
__ Ret(gt);
// String value => false iff empty, i.e., length is zero
__ ldr(tos_, FieldMemOperand(tos_, String::kLengthOffset));
// If length is zero, "tos_" contains zero ==> false.
// If length is not zero, "tos_" contains a non-zero value ==> true.
__ Ret();
// Return 0 in "tos_" for false .
__ bind(&false_result);
__ mov(tos_, Operand(0));
__ Ret();
}
// We fall into this code if the operands were Smis, but the result was
// not (eg. overflow). We branch into this code (to the not_smi label) if
// the operands were not both Smi. The operands are in r0 and r1. In order
// to call the C-implemented binary fp operation routines we need to end up
// with the double precision floating point operands in r0 and r1 (for the
// value in r1) and r2 and r3 (for the value in r0).
void GenericBinaryOpStub::HandleBinaryOpSlowCases(
MacroAssembler* masm,
Label* not_smi,
Register lhs,
Register rhs,
const Builtins::JavaScript& builtin) {
Label slow, slow_reverse, do_the_call;
bool use_fp_registers = CpuFeatures::IsSupported(VFP3) && Token::MOD != op_;
ASSERT((lhs.is(r0) && rhs.is(r1)) || (lhs.is(r1) && rhs.is(r0)));
Register heap_number_map = r6;
if (ShouldGenerateSmiCode()) {
__ LoadRoot(heap_number_map, Heap::kHeapNumberMapRootIndex);
// Smi-smi case (overflow).
// Since both are Smis there is no heap number to overwrite, so allocate.
// The new heap number is in r5. r3 and r7 are scratch.
__ AllocateHeapNumber(
r5, r3, r7, heap_number_map, lhs.is(r0) ? &slow_reverse : &slow);
// If we have floating point hardware, inline ADD, SUB, MUL, and DIV,
// using registers d7 and d6 for the double values.
if (CpuFeatures::IsSupported(VFP3)) {
CpuFeatures::Scope scope(VFP3);
__ mov(r7, Operand(rhs, ASR, kSmiTagSize));
__ vmov(s15, r7);
__ vcvt_f64_s32(d7, s15);
__ mov(r7, Operand(lhs, ASR, kSmiTagSize));
__ vmov(s13, r7);
__ vcvt_f64_s32(d6, s13);
if (!use_fp_registers) {
__ vmov(r2, r3, d7);
__ vmov(r0, r1, d6);
}
} else {
// Write Smi from rhs to r3 and r2 in double format. r9 is scratch.
__ mov(r7, Operand(rhs));
ConvertToDoubleStub stub1(r3, r2, r7, r9);
__ push(lr);
__ Call(stub1.GetCode(), RelocInfo::CODE_TARGET);
// Write Smi from lhs to r1 and r0 in double format. r9 is scratch.
__ mov(r7, Operand(lhs));
ConvertToDoubleStub stub2(r1, r0, r7, r9);
__ Call(stub2.GetCode(), RelocInfo::CODE_TARGET);
__ pop(lr);
}
__ jmp(&do_the_call); // Tail call. No return.
}
// We branch here if at least one of r0 and r1 is not a Smi.
__ bind(not_smi);
__ LoadRoot(heap_number_map, Heap::kHeapNumberMapRootIndex);
// After this point we have the left hand side in r1 and the right hand side
// in r0.
if (lhs.is(r0)) {
__ Swap(r0, r1, ip);
}
// The type transition also calculates the answer.
bool generate_code_to_calculate_answer = true;
if (ShouldGenerateFPCode()) {
if (runtime_operands_type_ == BinaryOpIC::DEFAULT) {
switch (op_) {
case Token::ADD:
case Token::SUB:
case Token::MUL:
case Token::DIV:
GenerateTypeTransition(masm); // Tail call.
generate_code_to_calculate_answer = false;
break;
default:
break;
}
}
if (generate_code_to_calculate_answer) {
Label r0_is_smi, r1_is_smi, finished_loading_r0, finished_loading_r1;
if (mode_ == NO_OVERWRITE) {
// In the case where there is no chance of an overwritable float we may
// as well do the allocation immediately while r0 and r1 are untouched.
__ AllocateHeapNumber(r5, r3, r7, heap_number_map, &slow);
}
// Move r0 to a double in r2-r3.
__ tst(r0, Operand(kSmiTagMask));
__ b(eq, &r0_is_smi); // It's a Smi so don't check it's a heap number.
__ ldr(r4, FieldMemOperand(r0, HeapObject::kMapOffset));
__ AssertRegisterIsRoot(heap_number_map, Heap::kHeapNumberMapRootIndex);
__ cmp(r4, heap_number_map);
__ b(ne, &slow);
if (mode_ == OVERWRITE_RIGHT) {
__ mov(r5, Operand(r0)); // Overwrite this heap number.
}
if (use_fp_registers) {
CpuFeatures::Scope scope(VFP3);
// Load the double from tagged HeapNumber r0 to d7.
__ sub(r7, r0, Operand(kHeapObjectTag));
__ vldr(d7, r7, HeapNumber::kValueOffset);
} else {
// Calling convention says that second double is in r2 and r3.
__ Ldrd(r2, r3, FieldMemOperand(r0, HeapNumber::kValueOffset));
}
__ jmp(&finished_loading_r0);
__ bind(&r0_is_smi);
if (mode_ == OVERWRITE_RIGHT) {
// We can't overwrite a Smi so get address of new heap number into r5.
__ AllocateHeapNumber(r5, r4, r7, heap_number_map, &slow);
}
if (CpuFeatures::IsSupported(VFP3)) {
CpuFeatures::Scope scope(VFP3);
// Convert smi in r0 to double in d7.
__ mov(r7, Operand(r0, ASR, kSmiTagSize));
__ vmov(s15, r7);
__ vcvt_f64_s32(d7, s15);
if (!use_fp_registers) {
__ vmov(r2, r3, d7);
}
} else {
// Write Smi from r0 to r3 and r2 in double format.
__ mov(r7, Operand(r0));
ConvertToDoubleStub stub3(r3, r2, r7, r4);
__ push(lr);
__ Call(stub3.GetCode(), RelocInfo::CODE_TARGET);
__ pop(lr);
}
// HEAP_NUMBERS stub is slower than GENERIC on a pair of smis.
// r0 is known to be a smi. If r1 is also a smi then switch to GENERIC.
Label r1_is_not_smi;
if (runtime_operands_type_ == BinaryOpIC::HEAP_NUMBERS) {
__ tst(r1, Operand(kSmiTagMask));
__ b(ne, &r1_is_not_smi);
GenerateTypeTransition(masm); // Tail call.
}
__ bind(&finished_loading_r0);
// Move r1 to a double in r0-r1.
__ tst(r1, Operand(kSmiTagMask));
__ b(eq, &r1_is_smi); // It's a Smi so don't check it's a heap number.
__ bind(&r1_is_not_smi);
__ ldr(r4, FieldMemOperand(r1, HeapNumber::kMapOffset));
__ AssertRegisterIsRoot(heap_number_map, Heap::kHeapNumberMapRootIndex);
__ cmp(r4, heap_number_map);
__ b(ne, &slow);
if (mode_ == OVERWRITE_LEFT) {
__ mov(r5, Operand(r1)); // Overwrite this heap number.
}
if (use_fp_registers) {
CpuFeatures::Scope scope(VFP3);
// Load the double from tagged HeapNumber r1 to d6.
__ sub(r7, r1, Operand(kHeapObjectTag));
__ vldr(d6, r7, HeapNumber::kValueOffset);
} else {
// Calling convention says that first double is in r0 and r1.
__ Ldrd(r0, r1, FieldMemOperand(r1, HeapNumber::kValueOffset));
}
__ jmp(&finished_loading_r1);
__ bind(&r1_is_smi);
if (mode_ == OVERWRITE_LEFT) {
// We can't overwrite a Smi so get address of new heap number into r5.
__ AllocateHeapNumber(r5, r4, r7, heap_number_map, &slow);
}
if (CpuFeatures::IsSupported(VFP3)) {
CpuFeatures::Scope scope(VFP3);
// Convert smi in r1 to double in d6.
__ mov(r7, Operand(r1, ASR, kSmiTagSize));
__ vmov(s13, r7);
__ vcvt_f64_s32(d6, s13);
if (!use_fp_registers) {
__ vmov(r0, r1, d6);
}
} else {
// Write Smi from r1 to r1 and r0 in double format.
__ mov(r7, Operand(r1));
ConvertToDoubleStub stub4(r1, r0, r7, r9);
__ push(lr);
__ Call(stub4.GetCode(), RelocInfo::CODE_TARGET);
__ pop(lr);
}
__ bind(&finished_loading_r1);
}
if (generate_code_to_calculate_answer || do_the_call.is_linked()) {
__ bind(&do_the_call);
// If we are inlining the operation using VFP3 instructions for
// add, subtract, multiply, or divide, the arguments are in d6 and d7.
if (use_fp_registers) {
CpuFeatures::Scope scope(VFP3);
// ARMv7 VFP3 instructions to implement
// double precision, add, subtract, multiply, divide.
if (Token::MUL == op_) {
__ vmul(d5, d6, d7);
} else if (Token::DIV == op_) {
__ vdiv(d5, d6, d7);
} else if (Token::ADD == op_) {
__ vadd(d5, d6, d7);
} else if (Token::SUB == op_) {
__ vsub(d5, d6, d7);
} else {
UNREACHABLE();
}
__ sub(r0, r5, Operand(kHeapObjectTag));
__ vstr(d5, r0, HeapNumber::kValueOffset);
__ add(r0, r0, Operand(kHeapObjectTag));
__ mov(pc, lr);
} else {
// If we did not inline the operation, then the arguments are in:
// r0: Left value (least significant part of mantissa).
// r1: Left value (sign, exponent, top of mantissa).
// r2: Right value (least significant part of mantissa).
// r3: Right value (sign, exponent, top of mantissa).
// r5: Address of heap number for result.
__ push(lr); // For later.
__ PrepareCallCFunction(4, r4); // Two doubles count as 4 arguments.
// Call C routine that may not cause GC or other trouble. r5 is callee
// save.
__ CallCFunction(ExternalReference::double_fp_operation(op_), 4);
// Store answer in the overwritable heap number.
#if !defined(USE_ARM_EABI)
// Double returned in fp coprocessor register 0 and 1, encoded as
// register cr8. Offsets must be divisible by 4 for coprocessor so we
// need to substract the tag from r5.
__ sub(r4, r5, Operand(kHeapObjectTag));
__ stc(p1, cr8, MemOperand(r4, HeapNumber::kValueOffset));
#else
// Double returned in registers 0 and 1.
__ Strd(r0, r1, FieldMemOperand(r5, HeapNumber::kValueOffset));
#endif
__ mov(r0, Operand(r5));
// And we are done.
__ pop(pc);
}
}
}
if (!generate_code_to_calculate_answer &&
!slow_reverse.is_linked() &&
!slow.is_linked()) {
return;
}
if (lhs.is(r0)) {
__ b(&slow);
__ bind(&slow_reverse);
__ Swap(r0, r1, ip);
}
heap_number_map = no_reg; // Don't use this any more from here on.
// We jump to here if something goes wrong (one param is not a number of any
// sort or new-space allocation fails).
__ bind(&slow);
// Push arguments to the stack
__ Push(r1, r0);
if (Token::ADD == op_) {
// Test for string arguments before calling runtime.
// r1 : first argument
// r0 : second argument
// sp[0] : second argument
// sp[4] : first argument
Label not_strings, not_string1, string1, string1_smi2;
__ tst(r1, Operand(kSmiTagMask));
__ b(eq, &not_string1);
__ CompareObjectType(r1, r2, r2, FIRST_NONSTRING_TYPE);
__ b(ge, &not_string1);
// First argument is a a string, test second.
__ tst(r0, Operand(kSmiTagMask));
__ b(eq, &string1_smi2);
__ CompareObjectType(r0, r2, r2, FIRST_NONSTRING_TYPE);
__ b(ge, &string1);
// First and second argument are strings.
StringAddStub string_add_stub(NO_STRING_CHECK_IN_STUB);
__ TailCallStub(&string_add_stub);
__ bind(&string1_smi2);
// First argument is a string, second is a smi. Try to lookup the number
// string for the smi in the number string cache.
NumberToStringStub::GenerateLookupNumberStringCache(
masm, r0, r2, r4, r5, r6, true, &string1);
// Replace second argument on stack and tailcall string add stub to make
// the result.
__ str(r2, MemOperand(sp, 0));
__ TailCallStub(&string_add_stub);
// Only first argument is a string.
__ bind(&string1);
__ InvokeBuiltin(Builtins::STRING_ADD_LEFT, JUMP_JS);
// First argument was not a string, test second.
__ bind(&not_string1);
__ tst(r0, Operand(kSmiTagMask));
__ b(eq, &not_strings);
__ CompareObjectType(r0, r2, r2, FIRST_NONSTRING_TYPE);
__ b(ge, &not_strings);
// Only second argument is a string.
__ InvokeBuiltin(Builtins::STRING_ADD_RIGHT, JUMP_JS);
__ bind(&not_strings);
}
__ InvokeBuiltin(builtin, JUMP_JS); // Tail call. No return.
}
// Tries to get a signed int32 out of a double precision floating point heap
// number. Rounds towards 0. Fastest for doubles that are in the ranges
// -0x7fffffff to -0x40000000 or 0x40000000 to 0x7fffffff. This corresponds
// almost to the range of signed int32 values that are not Smis. Jumps to the
// label 'slow' if the double isn't in the range -0x80000000.0 to 0x80000000.0
// (excluding the endpoints).
static void GetInt32(MacroAssembler* masm,
Register source,
Register dest,
Register scratch,
Register scratch2,
Label* slow) {
Label right_exponent, done;
// Get exponent word.
__ ldr(scratch, FieldMemOperand(source, HeapNumber::kExponentOffset));
// Get exponent alone in scratch2.
__ Ubfx(scratch2,
scratch,
HeapNumber::kExponentShift,
HeapNumber::kExponentBits);
// Load dest with zero. We use this either for the final shift or
// for the answer.
__ mov(dest, Operand(0));
// Check whether the exponent matches a 32 bit signed int that is not a Smi.
// A non-Smi integer is 1.xxx * 2^30 so the exponent is 30 (biased). This is
// the exponent that we are fastest at and also the highest exponent we can
// handle here.
const uint32_t non_smi_exponent = HeapNumber::kExponentBias + 30;
// The non_smi_exponent, 0x41d, is too big for ARM's immediate field so we
// split it up to avoid a constant pool entry. You can't do that in general
// for cmp because of the overflow flag, but we know the exponent is in the
// range 0-2047 so there is no overflow.
int fudge_factor = 0x400;
__ sub(scratch2, scratch2, Operand(fudge_factor));
__ cmp(scratch2, Operand(non_smi_exponent - fudge_factor));
// If we have a match of the int32-but-not-Smi exponent then skip some logic.
__ b(eq, &right_exponent);
// If the exponent is higher than that then go to slow case. This catches
// numbers that don't fit in a signed int32, infinities and NaNs.
__ b(gt, slow);
// We know the exponent is smaller than 30 (biased). If it is less than
// 0 (biased) then the number is smaller in magnitude than 1.0 * 2^0, ie
// it rounds to zero.
const uint32_t zero_exponent = HeapNumber::kExponentBias + 0;
__ sub(scratch2, scratch2, Operand(zero_exponent - fudge_factor), SetCC);
// Dest already has a Smi zero.
__ b(lt, &done);
if (!CpuFeatures::IsSupported(VFP3)) {
// We have an exponent between 0 and 30 in scratch2. Subtract from 30 to
// get how much to shift down.
__ rsb(dest, scratch2, Operand(30));
}
__ bind(&right_exponent);
if (CpuFeatures::IsSupported(VFP3)) {
CpuFeatures::Scope scope(VFP3);
// ARMv7 VFP3 instructions implementing double precision to integer
// conversion using round to zero.
__ ldr(scratch2, FieldMemOperand(source, HeapNumber::kMantissaOffset));
__ vmov(d7, scratch2, scratch);
__ vcvt_s32_f64(s15, d7);
__ vmov(dest, s15);
} else {
// Get the top bits of the mantissa.
__ and_(scratch2, scratch, Operand(HeapNumber::kMantissaMask));
// Put back the implicit 1.
__ orr(scratch2, scratch2, Operand(1 << HeapNumber::kExponentShift));
// Shift up the mantissa bits to take up the space the exponent used to
// take. We just orred in the implicit bit so that took care of one and
// we want to leave the sign bit 0 so we subtract 2 bits from the shift
// distance.
const int shift_distance = HeapNumber::kNonMantissaBitsInTopWord - 2;
__ mov(scratch2, Operand(scratch2, LSL, shift_distance));
// Put sign in zero flag.
__ tst(scratch, Operand(HeapNumber::kSignMask));
// Get the second half of the double. For some exponents we don't
// actually need this because the bits get shifted out again, but
// it's probably slower to test than just to do it.
__ ldr(scratch, FieldMemOperand(source, HeapNumber::kMantissaOffset));
// Shift down 22 bits to get the last 10 bits.
__ orr(scratch, scratch2, Operand(scratch, LSR, 32 - shift_distance));
// Move down according to the exponent.
__ mov(dest, Operand(scratch, LSR, dest));
// Fix sign if sign bit was set.
__ rsb(dest, dest, Operand(0), LeaveCC, ne);
}
__ bind(&done);
}
// For bitwise ops where the inputs are not both Smis we here try to determine
// whether both inputs are either Smis or at least heap numbers that can be
// represented by a 32 bit signed value. We truncate towards zero as required
// by the ES spec. If this is the case we do the bitwise op and see if the
// result is a Smi. If so, great, otherwise we try to find a heap number to
// write the answer into (either by allocating or by overwriting).
// On entry the operands are in lhs and rhs. On exit the answer is in r0.
void GenericBinaryOpStub::HandleNonSmiBitwiseOp(MacroAssembler* masm,
Register lhs,
Register rhs) {
Label slow, result_not_a_smi;
Label rhs_is_smi, lhs_is_smi;
Label done_checking_rhs, done_checking_lhs;
Register heap_number_map = r6;
__ LoadRoot(heap_number_map, Heap::kHeapNumberMapRootIndex);
__ tst(lhs, Operand(kSmiTagMask));
__ b(eq, &lhs_is_smi); // It's a Smi so don't check it's a heap number.
__ ldr(r4, FieldMemOperand(lhs, HeapNumber::kMapOffset));
__ cmp(r4, heap_number_map);
__ b(ne, &slow);
GetInt32(masm, lhs, r3, r5, r4, &slow);
__ jmp(&done_checking_lhs);
__ bind(&lhs_is_smi);
__ mov(r3, Operand(lhs, ASR, 1));
__ bind(&done_checking_lhs);
__ tst(rhs, Operand(kSmiTagMask));
__ b(eq, &rhs_is_smi); // It's a Smi so don't check it's a heap number.
__ ldr(r4, FieldMemOperand(rhs, HeapNumber::kMapOffset));
__ cmp(r4, heap_number_map);
__ b(ne, &slow);
GetInt32(masm, rhs, r2, r5, r4, &slow);
__ jmp(&done_checking_rhs);
__ bind(&rhs_is_smi);
__ mov(r2, Operand(rhs, ASR, 1));
__ bind(&done_checking_rhs);
ASSERT(((lhs.is(r0) && rhs.is(r1)) || (lhs.is(r1) && rhs.is(r0))));
// r0 and r1: Original operands (Smi or heap numbers).
// r2 and r3: Signed int32 operands.
switch (op_) {
case Token::BIT_OR: __ orr(r2, r2, Operand(r3)); break;
case Token::BIT_XOR: __ eor(r2, r2, Operand(r3)); break;
case Token::BIT_AND: __ and_(r2, r2, Operand(r3)); break;
case Token::SAR:
// Use only the 5 least significant bits of the shift count.
__ and_(r2, r2, Operand(0x1f));
__ mov(r2, Operand(r3, ASR, r2));
break;
case Token::SHR:
// Use only the 5 least significant bits of the shift count.
__ and_(r2, r2, Operand(0x1f));
__ mov(r2, Operand(r3, LSR, r2), SetCC);
// SHR is special because it is required to produce a positive answer.
// The code below for writing into heap numbers isn't capable of writing
// the register as an unsigned int so we go to slow case if we hit this
// case.
if (CpuFeatures::IsSupported(VFP3)) {
__ b(mi, &result_not_a_smi);
} else {
__ b(mi, &slow);
}
break;
case Token::SHL:
// Use only the 5 least significant bits of the shift count.
__ and_(r2, r2, Operand(0x1f));
__ mov(r2, Operand(r3, LSL, r2));
break;
default: UNREACHABLE();
}
// check that the *signed* result fits in a smi
__ add(r3, r2, Operand(0x40000000), SetCC);
__ b(mi, &result_not_a_smi);
__ mov(r0, Operand(r2, LSL, kSmiTagSize));
__ Ret();
Label have_to_allocate, got_a_heap_number;
__ bind(&result_not_a_smi);
switch (mode_) {
case OVERWRITE_RIGHT: {
__ tst(rhs, Operand(kSmiTagMask));
__ b(eq, &have_to_allocate);
__ mov(r5, Operand(rhs));
break;
}
case OVERWRITE_LEFT: {
__ tst(lhs, Operand(kSmiTagMask));
__ b(eq, &have_to_allocate);
__ mov(r5, Operand(lhs));
break;
}
case NO_OVERWRITE: {
// Get a new heap number in r5. r4 and r7 are scratch.
__ AllocateHeapNumber(r5, r4, r7, heap_number_map, &slow);
}
default: break;
}
__ bind(&got_a_heap_number);
// r2: Answer as signed int32.
// r5: Heap number to write answer into.
// Nothing can go wrong now, so move the heap number to r0, which is the
// result.
__ mov(r0, Operand(r5));
if (CpuFeatures::IsSupported(VFP3)) {
// Convert the int32 in r2 to the heap number in r0. r3 is corrupted.
CpuFeatures::Scope scope(VFP3);
__ vmov(s0, r2);
if (op_ == Token::SHR) {
__ vcvt_f64_u32(d0, s0);
} else {
__ vcvt_f64_s32(d0, s0);
}
__ sub(r3, r0, Operand(kHeapObjectTag));
__ vstr(d0, r3, HeapNumber::kValueOffset);
__ Ret();
} else {
// Tail call that writes the int32 in r2 to the heap number in r0, using
// r3 as scratch. r0 is preserved and returned.
WriteInt32ToHeapNumberStub stub(r2, r0, r3);
__ TailCallStub(&stub);
}
if (mode_ != NO_OVERWRITE) {
__ bind(&have_to_allocate);
// Get a new heap number in r5. r4 and r7 are scratch.
__ AllocateHeapNumber(r5, r4, r7, heap_number_map, &slow);
__ jmp(&got_a_heap_number);
}
// If all else failed then we go to the runtime system.
__ bind(&slow);
__ Push(lhs, rhs); // Restore stack.
switch (op_) {
case Token::BIT_OR:
__ InvokeBuiltin(Builtins::BIT_OR, JUMP_JS);
break;
case Token::BIT_AND:
__ InvokeBuiltin(Builtins::BIT_AND, JUMP_JS);
break;
case Token::BIT_XOR:
__ InvokeBuiltin(Builtins::BIT_XOR, JUMP_JS);
break;
case Token::SAR:
__ InvokeBuiltin(Builtins::SAR, JUMP_JS);
break;
case Token::SHR:
__ InvokeBuiltin(Builtins::SHR, JUMP_JS);
break;
case Token::SHL:
__ InvokeBuiltin(Builtins::SHL, JUMP_JS);
break;
default:
UNREACHABLE();
}
}
// This function takes the known int in a register for the cases
// where it doesn't know a good trick, and may deliver
// a result that needs shifting.
static void MultiplyByKnownIntInStub(
MacroAssembler* masm,
Register result,
Register source,
Register known_int_register, // Smi tagged.
int known_int,
int* required_shift) { // Including Smi tag shift
switch (known_int) {
case 3:
__ add(result, source, Operand(source, LSL, 1));
*required_shift = 1;
break;
case 5:
__ add(result, source, Operand(source, LSL, 2));
*required_shift = 1;
break;
case 6:
__ add(result, source, Operand(source, LSL, 1));
*required_shift = 2;
break;
case 7:
__ rsb(result, source, Operand(source, LSL, 3));
*required_shift = 1;
break;
case 9:
__ add(result, source, Operand(source, LSL, 3));
*required_shift = 1;
break;
case 10:
__ add(result, source, Operand(source, LSL, 2));
*required_shift = 2;
break;
default:
ASSERT(!IsPowerOf2(known_int)); // That would be very inefficient.
__ mul(result, source, known_int_register);
*required_shift = 0;
}
}
// This uses versions of the sum-of-digits-to-see-if-a-number-is-divisible-by-3
// trick. See http://en.wikipedia.org/wiki/Divisibility_rule
// Takes the sum of the digits base (mask + 1) repeatedly until we have a
// number from 0 to mask. On exit the 'eq' condition flags are set if the
// answer is exactly the mask.
void IntegerModStub::DigitSum(MacroAssembler* masm,
Register lhs,
int mask,
int shift,
Label* entry) {
ASSERT(mask > 0);
ASSERT(mask <= 0xff); // This ensures we don't need ip to use it.
Label loop;
__ bind(&loop);
__ and_(ip, lhs, Operand(mask));
__ add(lhs, ip, Operand(lhs, LSR, shift));
__ bind(entry);
__ cmp(lhs, Operand(mask));
__ b(gt, &loop);
}
void IntegerModStub::DigitSum(MacroAssembler* masm,
Register lhs,
Register scratch,
int mask,
int shift1,
int shift2,
Label* entry) {
ASSERT(mask > 0);
ASSERT(mask <= 0xff); // This ensures we don't need ip to use it.
Label loop;
__ bind(&loop);
__ bic(scratch, lhs, Operand(mask));
__ and_(ip, lhs, Operand(mask));
__ add(lhs, ip, Operand(lhs, LSR, shift1));
__ add(lhs, lhs, Operand(scratch, LSR, shift2));
__ bind(entry);
__ cmp(lhs, Operand(mask));
__ b(gt, &loop);
}
// Splits the number into two halves (bottom half has shift bits). The top
// half is subtracted from the bottom half. If the result is negative then
// rhs is added.
void IntegerModStub::ModGetInRangeBySubtraction(MacroAssembler* masm,
Register lhs,
int shift,
int rhs) {
int mask = (1 << shift) - 1;
__ and_(ip, lhs, Operand(mask));
__ sub(lhs, ip, Operand(lhs, LSR, shift), SetCC);
__ add(lhs, lhs, Operand(rhs), LeaveCC, mi);
}
void IntegerModStub::ModReduce(MacroAssembler* masm,
Register lhs,
int max,
int denominator) {
int limit = denominator;
while (limit * 2 <= max) limit *= 2;
while (limit >= denominator) {
__ cmp(lhs, Operand(limit));
__ sub(lhs, lhs, Operand(limit), LeaveCC, ge);
limit >>= 1;
}
}
void IntegerModStub::ModAnswer(MacroAssembler* masm,
Register result,
Register shift_distance,
Register mask_bits,
Register sum_of_digits) {
__ add(result, mask_bits, Operand(sum_of_digits, LSL, shift_distance));
__ Ret();
}
// See comment for class.
void IntegerModStub::Generate(MacroAssembler* masm) {
__ mov(lhs_, Operand(lhs_, LSR, shift_distance_));
__ bic(odd_number_, odd_number_, Operand(1));
__ mov(odd_number_, Operand(odd_number_, LSL, 1));
// We now have (odd_number_ - 1) * 2 in the register.
// Build a switch out of branches instead of data because it avoids
// having to teach the assembler about intra-code-object pointers
// that are not in relative branch instructions.
Label mod3, mod5, mod7, mod9, mod11, mod13, mod15, mod17, mod19;
Label mod21, mod23, mod25;
{ Assembler::BlockConstPoolScope block_const_pool(masm);
__ add(pc, pc, Operand(odd_number_));
// When you read pc it is always 8 ahead, but when you write it you always
// write the actual value. So we put in two nops to take up the slack.
__ nop();
__ nop();
__ b(&mod3);
__ b(&mod5);
__ b(&mod7);
__ b(&mod9);
__ b(&mod11);
__ b(&mod13);
__ b(&mod15);
__ b(&mod17);
__ b(&mod19);
__ b(&mod21);
__ b(&mod23);
__ b(&mod25);
}
// For each denominator we find a multiple that is almost only ones
// when expressed in binary. Then we do the sum-of-digits trick for
// that number. If the multiple is not 1 then we have to do a little
// more work afterwards to get the answer into the 0-denominator-1
// range.
DigitSum(masm, lhs_, 3, 2, &mod3); // 3 = b11.
__ sub(lhs_, lhs_, Operand(3), LeaveCC, eq);
ModAnswer(masm, result_, shift_distance_, mask_bits_, lhs_);
DigitSum(masm, lhs_, 0xf, 4, &mod5); // 5 * 3 = b1111.
ModGetInRangeBySubtraction(masm, lhs_, 2, 5);
ModAnswer(masm, result_, shift_distance_, mask_bits_, lhs_);
DigitSum(masm, lhs_, 7, 3, &mod7); // 7 = b111.
__ sub(lhs_, lhs_, Operand(7), LeaveCC, eq);
ModAnswer(masm, result_, shift_distance_, mask_bits_, lhs_);
DigitSum(masm, lhs_, 0x3f, 6, &mod9); // 7 * 9 = b111111.
ModGetInRangeBySubtraction(masm, lhs_, 3, 9);
ModAnswer(masm, result_, shift_distance_, mask_bits_, lhs_);
DigitSum(masm, lhs_, r5, 0x3f, 6, 3, &mod11); // 5 * 11 = b110111.
ModReduce(masm, lhs_, 0x3f, 11);
ModAnswer(masm, result_, shift_distance_, mask_bits_, lhs_);
DigitSum(masm, lhs_, r5, 0xff, 8, 5, &mod13); // 19 * 13 = b11110111.
ModReduce(masm, lhs_, 0xff, 13);
ModAnswer(masm, result_, shift_distance_, mask_bits_, lhs_);
DigitSum(masm, lhs_, 0xf, 4, &mod15); // 15 = b1111.
__ sub(lhs_, lhs_, Operand(15), LeaveCC, eq);
ModAnswer(masm, result_, shift_distance_, mask_bits_, lhs_);
DigitSum(masm, lhs_, 0xff, 8, &mod17); // 15 * 17 = b11111111.
ModGetInRangeBySubtraction(masm, lhs_, 4, 17);
ModAnswer(masm, result_, shift_distance_, mask_bits_, lhs_);
DigitSum(masm, lhs_, r5, 0xff, 8, 5, &mod19); // 13 * 19 = b11110111.
ModReduce(masm, lhs_, 0xff, 19);
ModAnswer(masm, result_, shift_distance_, mask_bits_, lhs_);
DigitSum(masm, lhs_, 0x3f, 6, &mod21); // 3 * 21 = b111111.
ModReduce(masm, lhs_, 0x3f, 21);
ModAnswer(masm, result_, shift_distance_, mask_bits_, lhs_);
DigitSum(masm, lhs_, r5, 0xff, 8, 7, &mod23); // 11 * 23 = b11111101.
ModReduce(masm, lhs_, 0xff, 23);
ModAnswer(masm, result_, shift_distance_, mask_bits_, lhs_);
DigitSum(masm, lhs_, r5, 0x7f, 7, 6, &mod25); // 5 * 25 = b1111101.
ModReduce(masm, lhs_, 0x7f, 25);
ModAnswer(masm, result_, shift_distance_, mask_bits_, lhs_);
}
void GenericBinaryOpStub::Generate(MacroAssembler* masm) {
// lhs_ : x
// rhs_ : y
// r0 : result
Register result = r0;
Register lhs = lhs_;
Register rhs = rhs_;
// This code can't cope with other register allocations yet.
ASSERT(result.is(r0) &&
((lhs.is(r0) && rhs.is(r1)) ||
(lhs.is(r1) && rhs.is(r0))));
Register smi_test_reg = r7;
Register scratch = r9;
// All ops need to know whether we are dealing with two Smis. Set up
// smi_test_reg to tell us that.
if (ShouldGenerateSmiCode()) {
__ orr(smi_test_reg, lhs, Operand(rhs));
}
switch (op_) {
case Token::ADD: {
Label not_smi;
// Fast path.
if (ShouldGenerateSmiCode()) {
STATIC_ASSERT(kSmiTag == 0); // Adjust code below.
__ tst(smi_test_reg, Operand(kSmiTagMask));
__ b(ne, &not_smi);
__ add(r0, r1, Operand(r0), SetCC); // Add y optimistically.
// Return if no overflow.
__ Ret(vc);
__ sub(r0, r0, Operand(r1)); // Revert optimistic add.
}
HandleBinaryOpSlowCases(masm, &not_smi, lhs, rhs, Builtins::ADD);
break;
}
case Token::SUB: {
Label not_smi;
// Fast path.
if (ShouldGenerateSmiCode()) {
STATIC_ASSERT(kSmiTag == 0); // Adjust code below.
__ tst(smi_test_reg, Operand(kSmiTagMask));
__ b(ne, &not_smi);
if (lhs.is(r1)) {
__ sub(r0, r1, Operand(r0), SetCC); // Subtract y optimistically.
// Return if no overflow.
__ Ret(vc);
__ sub(r0, r1, Operand(r0)); // Revert optimistic subtract.
} else {
__ sub(r0, r0, Operand(r1), SetCC); // Subtract y optimistically.
// Return if no overflow.
__ Ret(vc);
__ add(r0, r0, Operand(r1)); // Revert optimistic subtract.
}
}
HandleBinaryOpSlowCases(masm, &not_smi, lhs, rhs, Builtins::SUB);
break;
}
case Token::MUL: {
Label not_smi, slow;
if (ShouldGenerateSmiCode()) {
STATIC_ASSERT(kSmiTag == 0); // adjust code below
__ tst(smi_test_reg, Operand(kSmiTagMask));
Register scratch2 = smi_test_reg;
smi_test_reg = no_reg;
__ b(ne, &not_smi);
// Remove tag from one operand (but keep sign), so that result is Smi.
__ mov(ip, Operand(rhs, ASR, kSmiTagSize));
// Do multiplication
// scratch = lower 32 bits of ip * lhs.
__ smull(scratch, scratch2, lhs, ip);
// Go slow on overflows (overflow bit is not set).
__ mov(ip, Operand(scratch, ASR, 31));
// No overflow if higher 33 bits are identical.
__ cmp(ip, Operand(scratch2));
__ b(ne, &slow);
// Go slow on zero result to handle -0.
__ tst(scratch, Operand(scratch));
__ mov(result, Operand(scratch), LeaveCC, ne);
__ Ret(ne);
// We need -0 if we were multiplying a negative number with 0 to get 0.
// We know one of them was zero.
__ add(scratch2, rhs, Operand(lhs), SetCC);
__ mov(result, Operand(Smi::FromInt(0)), LeaveCC, pl);
__ Ret(pl); // Return Smi 0 if the non-zero one was positive.
// Slow case. We fall through here if we multiplied a negative number
// with 0, because that would mean we should produce -0.
__ bind(&slow);
}
HandleBinaryOpSlowCases(masm, &not_smi, lhs, rhs, Builtins::MUL);
break;
}
case Token::DIV:
case Token::MOD: {
Label not_smi;
if (ShouldGenerateSmiCode() && specialized_on_rhs_) {
Label lhs_is_unsuitable;
__ BranchOnNotSmi(lhs, &not_smi);
if (IsPowerOf2(constant_rhs_)) {
if (op_ == Token::MOD) {
__ and_(rhs,
lhs,
Operand(0x80000000u | ((constant_rhs_ << kSmiTagSize) - 1)),
SetCC);
// We now have the answer, but if the input was negative we also
// have the sign bit. Our work is done if the result is
// positive or zero:
if (!rhs.is(r0)) {
__ mov(r0, rhs, LeaveCC, pl);
}
__ Ret(pl);
// A mod of a negative left hand side must return a negative number.
// Unfortunately if the answer is 0 then we must return -0. And we
// already optimistically trashed rhs so we may need to restore it.
__ eor(rhs, rhs, Operand(0x80000000u), SetCC);
// Next two instructions are conditional on the answer being -0.
__ mov(rhs, Operand(Smi::FromInt(constant_rhs_)), LeaveCC, eq);
__ b(eq, &lhs_is_unsuitable);
// We need to subtract the dividend. Eg. -3 % 4 == -3.
__ sub(result, rhs, Operand(Smi::FromInt(constant_rhs_)));
} else {
ASSERT(op_ == Token::DIV);
__ tst(lhs,
Operand(0x80000000u | ((constant_rhs_ << kSmiTagSize) - 1)));
__ b(ne, &lhs_is_unsuitable); // Go slow on negative or remainder.
int shift = 0;
int d = constant_rhs_;
while ((d & 1) == 0) {
d >>= 1;
shift++;
}
__ mov(r0, Operand(lhs, LSR, shift));
__ bic(r0, r0, Operand(kSmiTagMask));
}
} else {
// Not a power of 2.
__ tst(lhs, Operand(0x80000000u));
__ b(ne, &lhs_is_unsuitable);
// Find a fixed point reciprocal of the divisor so we can divide by
// multiplying.
double divisor = 1.0 / constant_rhs_;
int shift = 32;
double scale = 4294967296.0; // 1 << 32.
uint32_t mul;
// Maximise the precision of the fixed point reciprocal.
while (true) {
mul = static_cast<uint32_t>(scale * divisor);
if (mul >= 0x7fffffff) break;
scale *= 2.0;
shift++;
}
mul++;
Register scratch2 = smi_test_reg;
smi_test_reg = no_reg;
__ mov(scratch2, Operand(mul));
__ umull(scratch, scratch2, scratch2, lhs);
__ mov(scratch2, Operand(scratch2, LSR, shift - 31));
// scratch2 is lhs / rhs. scratch2 is not Smi tagged.
// rhs is still the known rhs. rhs is Smi tagged.
// lhs is still the unkown lhs. lhs is Smi tagged.
int required_scratch_shift = 0; // Including the Smi tag shift of 1.
// scratch = scratch2 * rhs.
MultiplyByKnownIntInStub(masm,
scratch,
scratch2,
rhs,
constant_rhs_,
&required_scratch_shift);
// scratch << required_scratch_shift is now the Smi tagged rhs *
// (lhs / rhs) where / indicates integer division.
if (op_ == Token::DIV) {
__ cmp(lhs, Operand(scratch, LSL, required_scratch_shift));
__ b(ne, &lhs_is_unsuitable); // There was a remainder.
__ mov(result, Operand(scratch2, LSL, kSmiTagSize));
} else {
ASSERT(op_ == Token::MOD);
__ sub(result, lhs, Operand(scratch, LSL, required_scratch_shift));
}
}
__ Ret();
__ bind(&lhs_is_unsuitable);
} else if (op_ == Token::MOD &&
runtime_operands_type_ != BinaryOpIC::HEAP_NUMBERS &&
runtime_operands_type_ != BinaryOpIC::STRINGS) {
// Do generate a bit of smi code for modulus even though the default for
// modulus is not to do it, but as the ARM processor has no coprocessor
// support for modulus checking for smis makes sense. We can handle
// 1 to 25 times any power of 2. This covers over half the numbers from
// 1 to 100 including all of the first 25. (Actually the constants < 10
// are handled above by reciprocal multiplication. We only get here for
// those cases if the right hand side is not a constant or for cases
// like 192 which is 3*2^6 and ends up in the 3 case in the integer mod
// stub.)
Label slow;
Label not_power_of_2;
ASSERT(!ShouldGenerateSmiCode());
STATIC_ASSERT(kSmiTag == 0); // Adjust code below.
// Check for two positive smis.
__ orr(smi_test_reg, lhs, Operand(rhs));
__ tst(smi_test_reg, Operand(0x80000000u | kSmiTagMask));
__ b(ne, &slow);
// Check that rhs is a power of two and not zero.
Register mask_bits = r3;
__ sub(scratch, rhs, Operand(1), SetCC);
__ b(mi, &slow);
__ and_(mask_bits, rhs, Operand(scratch), SetCC);
__ b(ne, &not_power_of_2);
// Calculate power of two modulus.
__ and_(result, lhs, Operand(scratch));
__ Ret();
__ bind(&not_power_of_2);
__ eor(scratch, scratch, Operand(mask_bits));
// At least two bits are set in the modulus. The high one(s) are in
// mask_bits and the low one is scratch + 1.
__ and_(mask_bits, scratch, Operand(lhs));
Register shift_distance = scratch;
scratch = no_reg;
// The rhs consists of a power of 2 multiplied by some odd number.
// The power-of-2 part we handle by putting the corresponding bits
// from the lhs in the mask_bits register, and the power in the
// shift_distance register. Shift distance is never 0 due to Smi
// tagging.
__ CountLeadingZeros(r4, shift_distance, shift_distance);
__ rsb(shift_distance, r4, Operand(32));
// Now we need to find out what the odd number is. The last bit is
// always 1.
Register odd_number = r4;
__ mov(odd_number, Operand(rhs, LSR, shift_distance));
__ cmp(odd_number, Operand(25));
__ b(gt, &slow);
IntegerModStub stub(
result, shift_distance, odd_number, mask_bits, lhs, r5);
__ Jump(stub.GetCode(), RelocInfo::CODE_TARGET); // Tail call.
__ bind(&slow);
}
HandleBinaryOpSlowCases(
masm,
&not_smi,
lhs,
rhs,
op_ == Token::MOD ? Builtins::MOD : Builtins::DIV);
break;
}
case Token::BIT_OR:
case Token::BIT_AND:
case Token::BIT_XOR:
case Token::SAR:
case Token::SHR:
case Token::SHL: {
Label slow;
STATIC_ASSERT(kSmiTag == 0); // adjust code below
__ tst(smi_test_reg, Operand(kSmiTagMask));
__ b(ne, &slow);
Register scratch2 = smi_test_reg;
smi_test_reg = no_reg;
switch (op_) {
case Token::BIT_OR: __ orr(result, rhs, Operand(lhs)); break;
case Token::BIT_AND: __ and_(result, rhs, Operand(lhs)); break;
case Token::BIT_XOR: __ eor(result, rhs, Operand(lhs)); break;
case Token::SAR:
// Remove tags from right operand.
__ GetLeastBitsFromSmi(scratch2, rhs, 5);
__ mov(result, Operand(lhs, ASR, scratch2));
// Smi tag result.
__ bic(result, result, Operand(kSmiTagMask));
break;
case Token::SHR:
// Remove tags from operands. We can't do this on a 31 bit number
// because then the 0s get shifted into bit 30 instead of bit 31.
__ mov(scratch, Operand(lhs, ASR, kSmiTagSize)); // x
__ GetLeastBitsFromSmi(scratch2, rhs, 5);
__ mov(scratch, Operand(scratch, LSR, scratch2));
// Unsigned shift is not allowed to produce a negative number, so
// check the sign bit and the sign bit after Smi tagging.
__ tst(scratch, Operand(0xc0000000));
__ b(ne, &slow);
// Smi tag result.
__ mov(result, Operand(scratch, LSL, kSmiTagSize));
break;
case Token::SHL:
// Remove tags from operands.
__ mov(scratch, Operand(lhs, ASR, kSmiTagSize)); // x
__ GetLeastBitsFromSmi(scratch2, rhs, 5);
__ mov(scratch, Operand(scratch, LSL, scratch2));
// Check that the signed result fits in a Smi.
__ add(scratch2, scratch, Operand(0x40000000), SetCC);
__ b(mi, &slow);
__ mov(result, Operand(scratch, LSL, kSmiTagSize));
break;
default: UNREACHABLE();
}
__ Ret();
__ bind(&slow);
HandleNonSmiBitwiseOp(masm, lhs, rhs);
break;
}
default: UNREACHABLE();
}
// This code should be unreachable.
__ stop("Unreachable");
// Generate an unreachable reference to the DEFAULT stub so that it can be
// found at the end of this stub when clearing ICs at GC.
// TODO(kaznacheev): Check performance impact and get rid of this.
if (runtime_operands_type_ != BinaryOpIC::DEFAULT) {
GenericBinaryOpStub uninit(MinorKey(), BinaryOpIC::DEFAULT);
__ CallStub(&uninit);
}
}
void GenericBinaryOpStub::GenerateTypeTransition(MacroAssembler* masm) {
Label get_result;
__ Push(r1, r0);
__ mov(r2, Operand(Smi::FromInt(MinorKey())));
__ mov(r1, Operand(Smi::FromInt(op_)));
__ mov(r0, Operand(Smi::FromInt(runtime_operands_type_)));
__ Push(r2, r1, r0);
__ TailCallExternalReference(
ExternalReference(IC_Utility(IC::kBinaryOp_Patch)),
5,
1);
}
Handle<Code> GetBinaryOpStub(int key, BinaryOpIC::TypeInfo type_info) {
GenericBinaryOpStub stub(key, type_info);
return stub.GetCode();
}
void TranscendentalCacheStub::Generate(MacroAssembler* masm) {
// Argument is a number and is on stack and in r0.
Label runtime_call;
Label input_not_smi;
Label loaded;
if (CpuFeatures::IsSupported(VFP3)) {
// Load argument and check if it is a smi.
__ BranchOnNotSmi(r0, &input_not_smi);
CpuFeatures::Scope scope(VFP3);
// Input is a smi. Convert to double and load the low and high words
// of the double into r2, r3.
__ IntegerToDoubleConversionWithVFP3(r0, r3, r2);
__ b(&loaded);
__ bind(&input_not_smi);
// Check if input is a HeapNumber.
__ CheckMap(r0,
r1,
Heap::kHeapNumberMapRootIndex,
&runtime_call,
true);
// Input is a HeapNumber. Load it to a double register and store the
// low and high words into r2, r3.
__ Ldrd(r2, r3, FieldMemOperand(r0, HeapNumber::kValueOffset));
__ bind(&loaded);
// r2 = low 32 bits of double value
// r3 = high 32 bits of double value
// Compute hash (the shifts are arithmetic):
// h = (low ^ high); h ^= h >> 16; h ^= h >> 8; h = h & (cacheSize - 1);
__ eor(r1, r2, Operand(r3));
__ eor(r1, r1, Operand(r1, ASR, 16));
__ eor(r1, r1, Operand(r1, ASR, 8));
ASSERT(IsPowerOf2(TranscendentalCache::kCacheSize));
__ And(r1, r1, Operand(TranscendentalCache::kCacheSize - 1));
// r2 = low 32 bits of double value.
// r3 = high 32 bits of double value.
// r1 = TranscendentalCache::hash(double value).
__ mov(r0,
Operand(ExternalReference::transcendental_cache_array_address()));
// r0 points to cache array.
__ ldr(r0, MemOperand(r0, type_ * sizeof(TranscendentalCache::caches_[0])));
// r0 points to the cache for the type type_.
// If NULL, the cache hasn't been initialized yet, so go through runtime.
__ cmp(r0, Operand(0));
__ b(eq, &runtime_call);
#ifdef DEBUG
// Check that the layout of cache elements match expectations.
{ TranscendentalCache::Element test_elem[2];
char* elem_start = reinterpret_cast<char*>(&test_elem[0]);
char* elem2_start = reinterpret_cast<char*>(&test_elem[1]);
char* elem_in0 = reinterpret_cast<char*>(&(test_elem[0].in[0]));
char* elem_in1 = reinterpret_cast<char*>(&(test_elem[0].in[1]));
char* elem_out = reinterpret_cast<char*>(&(test_elem[0].output));
CHECK_EQ(12, elem2_start - elem_start); // Two uint_32's and a pointer.
CHECK_EQ(0, elem_in0 - elem_start);
CHECK_EQ(kIntSize, elem_in1 - elem_start);
CHECK_EQ(2 * kIntSize, elem_out - elem_start);
}
#endif
// Find the address of the r1'st entry in the cache, i.e., &r0[r1*12].
__ add(r1, r1, Operand(r1, LSL, 1));
__ add(r0, r0, Operand(r1, LSL, 2));
// Check if cache matches: Double value is stored in uint32_t[2] array.
__ ldm(ia, r0, r4.bit()| r5.bit() | r6.bit());
__ cmp(r2, r4);
__ b(ne, &runtime_call);
__ cmp(r3, r5);
__ b(ne, &runtime_call);
// Cache hit. Load result, pop argument and return.
__ mov(r0, Operand(r6));
__ pop();
__ Ret();
}
__ bind(&runtime_call);
__ TailCallExternalReference(ExternalReference(RuntimeFunction()), 1, 1);
}
Runtime::FunctionId TranscendentalCacheStub::RuntimeFunction() {
switch (type_) {
// Add more cases when necessary.
case TranscendentalCache::SIN: return Runtime::kMath_sin;
case TranscendentalCache::COS: return Runtime::kMath_cos;
default:
UNIMPLEMENTED();
return Runtime::kAbort;
}
}
void StackCheckStub::Generate(MacroAssembler* masm) {
// Do tail-call to runtime routine. Runtime routines expect at least one
// argument, so give it a Smi.
__ mov(r0, Operand(Smi::FromInt(0)));
__ push(r0);
__ TailCallRuntime(Runtime::kStackGuard, 1, 1);
__ StubReturn(1);
}
void GenericUnaryOpStub::Generate(MacroAssembler* masm) {
Label slow, done;
Register heap_number_map = r6;
__ LoadRoot(heap_number_map, Heap::kHeapNumberMapRootIndex);
if (op_ == Token::SUB) {
// Check whether the value is a smi.
Label try_float;
__ tst(r0, Operand(kSmiTagMask));
__ b(ne, &try_float);
// Go slow case if the value of the expression is zero
// to make sure that we switch between 0 and -0.
if (negative_zero_ == kStrictNegativeZero) {
// If we have to check for zero, then we can check for the max negative
// smi while we are at it.
__ bic(ip, r0, Operand(0x80000000), SetCC);
__ b(eq, &slow);
__ rsb(r0, r0, Operand(0));
__ StubReturn(1);
} else {
// The value of the expression is a smi and 0 is OK for -0. Try
// optimistic subtraction '0 - value'.
__ rsb(r0, r0, Operand(0), SetCC);
__ StubReturn(1, vc);
// We don't have to reverse the optimistic neg since the only case
// where we fall through is the minimum negative Smi, which is the case
// where the neg leaves the register unchanged.
__ jmp(&slow); // Go slow on max negative Smi.
}
__ bind(&try_float);
__ ldr(r1, FieldMemOperand(r0, HeapObject::kMapOffset));
__ AssertRegisterIsRoot(heap_number_map, Heap::kHeapNumberMapRootIndex);
__ cmp(r1, heap_number_map);
__ b(ne, &slow);
// r0 is a heap number. Get a new heap number in r1.
if (overwrite_ == UNARY_OVERWRITE) {
__ ldr(r2, FieldMemOperand(r0, HeapNumber::kExponentOffset));
__ eor(r2, r2, Operand(HeapNumber::kSignMask)); // Flip sign.
__ str(r2, FieldMemOperand(r0, HeapNumber::kExponentOffset));
} else {
__ AllocateHeapNumber(r1, r2, r3, r6, &slow);
__ ldr(r3, FieldMemOperand(r0, HeapNumber::kMantissaOffset));
__ ldr(r2, FieldMemOperand(r0, HeapNumber::kExponentOffset));
__ str(r3, FieldMemOperand(r1, HeapNumber::kMantissaOffset));
__ eor(r2, r2, Operand(HeapNumber::kSignMask)); // Flip sign.
__ str(r2, FieldMemOperand(r1, HeapNumber::kExponentOffset));
__ mov(r0, Operand(r1));
}
} else if (op_ == Token::BIT_NOT) {
// Check if the operand is a heap number.
__ ldr(r1, FieldMemOperand(r0, HeapObject::kMapOffset));
__ AssertRegisterIsRoot(heap_number_map, Heap::kHeapNumberMapRootIndex);
__ cmp(r1, heap_number_map);
__ b(ne, &slow);
// Convert the heap number is r0 to an untagged integer in r1.
GetInt32(masm, r0, r1, r2, r3, &slow);
// Do the bitwise operation (move negated) and check if the result
// fits in a smi.
Label try_float;
__ mvn(r1, Operand(r1));
__ add(r2, r1, Operand(0x40000000), SetCC);
__ b(mi, &try_float);
__ mov(r0, Operand(r1, LSL, kSmiTagSize));
__ b(&done);
__ bind(&try_float);
if (!overwrite_ == UNARY_OVERWRITE) {
// Allocate a fresh heap number, but don't overwrite r0 until
// we're sure we can do it without going through the slow case
// that needs the value in r0.
__ AllocateHeapNumber(r2, r3, r4, r6, &slow);
__ mov(r0, Operand(r2));
}
if (CpuFeatures::IsSupported(VFP3)) {
// Convert the int32 in r1 to the heap number in r0. r2 is corrupted.
CpuFeatures::Scope scope(VFP3);
__ vmov(s0, r1);
__ vcvt_f64_s32(d0, s0);
__ sub(r2, r0, Operand(kHeapObjectTag));
__ vstr(d0, r2, HeapNumber::kValueOffset);
} else {
// WriteInt32ToHeapNumberStub does not trigger GC, so we do not
// have to set up a frame.
WriteInt32ToHeapNumberStub stub(r1, r0, r2);
__ push(lr);
__ Call(stub.GetCode(), RelocInfo::CODE_TARGET);
__ pop(lr);
}
} else {
UNIMPLEMENTED();
}
__ bind(&done);
__ StubReturn(1);
// Handle the slow case by jumping to the JavaScript builtin.
__ bind(&slow);
__ push(r0);
switch (op_) {
case Token::SUB:
__ InvokeBuiltin(Builtins::UNARY_MINUS, JUMP_JS);
break;
case Token::BIT_NOT:
__ InvokeBuiltin(Builtins::BIT_NOT, JUMP_JS);
break;
default:
UNREACHABLE();
}
}
void CEntryStub::GenerateThrowTOS(MacroAssembler* masm) {
// r0 holds the exception.
// Adjust this code if not the case.
STATIC_ASSERT(StackHandlerConstants::kSize == 4 * kPointerSize);
// Drop the sp to the top of the handler.
__ mov(r3, Operand(ExternalReference(Top::k_handler_address)));
__ ldr(sp, MemOperand(r3));
// Restore the next handler and frame pointer, discard handler state.
STATIC_ASSERT(StackHandlerConstants::kNextOffset == 0);
__ pop(r2);
__ str(r2, MemOperand(r3));
STATIC_ASSERT(StackHandlerConstants::kFPOffset == 2 * kPointerSize);
__ ldm(ia_w, sp, r3.bit() | fp.bit()); // r3: discarded state.
// Before returning we restore the context from the frame pointer if
// not NULL. The frame pointer is NULL in the exception handler of a
// JS entry frame.
__ cmp(fp, Operand(0));
// Set cp to NULL if fp is NULL.
__ mov(cp, Operand(0), LeaveCC, eq);
// Restore cp otherwise.
__ ldr(cp, MemOperand(fp, StandardFrameConstants::kContextOffset), ne);
#ifdef DEBUG
if (FLAG_debug_code) {
__ mov(lr, Operand(pc));
}
#endif
STATIC_ASSERT(StackHandlerConstants::kPCOffset == 3 * kPointerSize);
__ pop(pc);
}
void CEntryStub::GenerateThrowUncatchable(MacroAssembler* masm,
UncatchableExceptionType type) {
// Adjust this code if not the case.
STATIC_ASSERT(StackHandlerConstants::kSize == 4 * kPointerSize);
// Drop sp to the top stack handler.
__ mov(r3, Operand(ExternalReference(Top::k_handler_address)));
__ ldr(sp, MemOperand(r3));
// Unwind the handlers until the ENTRY handler is found.
Label loop, done;
__ bind(&loop);
// Load the type of the current stack handler.
const int kStateOffset = StackHandlerConstants::kStateOffset;
__ ldr(r2, MemOperand(sp, kStateOffset));
__ cmp(r2, Operand(StackHandler::ENTRY));
__ b(eq, &done);
// Fetch the next handler in the list.
const int kNextOffset = StackHandlerConstants::kNextOffset;
__ ldr(sp, MemOperand(sp, kNextOffset));
__ jmp(&loop);
__ bind(&done);
// Set the top handler address to next handler past the current ENTRY handler.
STATIC_ASSERT(StackHandlerConstants::kNextOffset == 0);
__ pop(r2);
__ str(r2, MemOperand(r3));
if (type == OUT_OF_MEMORY) {
// Set external caught exception to false.
ExternalReference external_caught(Top::k_external_caught_exception_address);
__ mov(r0, Operand(false));
__ mov(r2, Operand(external_caught));
__ str(r0, MemOperand(r2));
// Set pending exception and r0 to out of memory exception.
Failure* out_of_memory = Failure::OutOfMemoryException();
__ mov(r0, Operand(reinterpret_cast<int32_t>(out_of_memory)));
__ mov(r2, Operand(ExternalReference(Top::k_pending_exception_address)));
__ str(r0, MemOperand(r2));
}
// Stack layout at this point. See also StackHandlerConstants.
// sp -> state (ENTRY)
// fp
// lr
// Discard handler state (r2 is not used) and restore frame pointer.
STATIC_ASSERT(StackHandlerConstants::kFPOffset == 2 * kPointerSize);
__ ldm(ia_w, sp, r2.bit() | fp.bit()); // r2: discarded state.
// Before returning we restore the context from the frame pointer if
// not NULL. The frame pointer is NULL in the exception handler of a
// JS entry frame.
__ cmp(fp, Operand(0));
// Set cp to NULL if fp is NULL.
__ mov(cp, Operand(0), LeaveCC, eq);
// Restore cp otherwise.
__ ldr(cp, MemOperand(fp, StandardFrameConstants::kContextOffset), ne);
#ifdef DEBUG
if (FLAG_debug_code) {
__ mov(lr, Operand(pc));
}
#endif
STATIC_ASSERT(StackHandlerConstants::kPCOffset == 3 * kPointerSize);
__ pop(pc);
}
void CEntryStub::GenerateCore(MacroAssembler* masm,
Label* throw_normal_exception,
Label* throw_termination_exception,
Label* throw_out_of_memory_exception,
bool do_gc,
bool always_allocate,
int frame_alignment_skew) {
// r0: result parameter for PerformGC, if any
// r4: number of arguments including receiver (C callee-saved)
// r5: pointer to builtin function (C callee-saved)
// r6: pointer to the first argument (C callee-saved)
if (do_gc) {
// Passing r0.
__ PrepareCallCFunction(1, r1);
__ CallCFunction(ExternalReference::perform_gc_function(), 1);
}
ExternalReference scope_depth =
ExternalReference::heap_always_allocate_scope_depth();
if (always_allocate) {
__ mov(r0, Operand(scope_depth));
__ ldr(r1, MemOperand(r0));
__ add(r1, r1, Operand(1));
__ str(r1, MemOperand(r0));
}
// Call C built-in.
// r0 = argc, r1 = argv
__ mov(r0, Operand(r4));
__ mov(r1, Operand(r6));
int frame_alignment = MacroAssembler::ActivationFrameAlignment();
int frame_alignment_mask = frame_alignment - 1;
#if defined(V8_HOST_ARCH_ARM)
if (FLAG_debug_code) {
if (frame_alignment > kPointerSize) {
Label alignment_as_expected;
ASSERT(IsPowerOf2(frame_alignment));
__ sub(r2, sp, Operand(frame_alignment_skew));
__ tst(r2, Operand(frame_alignment_mask));
__ b(eq, &alignment_as_expected);
// Don't use Check here, as it will call Runtime_Abort re-entering here.
__ stop("Unexpected alignment");
__ bind(&alignment_as_expected);
}
}
#endif
// Just before the call (jump) below lr is pushed, so the actual alignment is
// adding one to the current skew.
int alignment_before_call =
(frame_alignment_skew + kPointerSize) & frame_alignment_mask;
if (alignment_before_call > 0) {
// Push until the alignment before the call is met.
__ mov(r2, Operand(0));
for (int i = alignment_before_call;
(i & frame_alignment_mask) != 0;
i += kPointerSize) {
__ push(r2);
}
}
// TODO(1242173): To let the GC traverse the return address of the exit
// frames, we need to know where the return address is. Right now,
// we push it on the stack to be able to find it again, but we never
// restore from it in case of changes, which makes it impossible to
// support moving the C entry code stub. This should be fixed, but currently
// this is OK because the CEntryStub gets generated so early in the V8 boot
// sequence that it is not moving ever.
masm->add(lr, pc, Operand(4)); // Compute return address: (pc + 8) + 4
masm->push(lr);
masm->Jump(r5);
// Restore sp back to before aligning the stack.
if (alignment_before_call > 0) {
__ add(sp, sp, Operand(alignment_before_call));
}
if (always_allocate) {
// It's okay to clobber r2 and r3 here. Don't mess with r0 and r1
// though (contain the result).
__ mov(r2, Operand(scope_depth));
__ ldr(r3, MemOperand(r2));
__ sub(r3, r3, Operand(1));
__ str(r3, MemOperand(r2));
}
// check for failure result
Label failure_returned;
STATIC_ASSERT(((kFailureTag + 1) & kFailureTagMask) == 0);
// Lower 2 bits of r2 are 0 iff r0 has failure tag.
__ add(r2, r0, Operand(1));
__ tst(r2, Operand(kFailureTagMask));
__ b(eq, &failure_returned);
// Exit C frame and return.
// r0:r1: result
// sp: stack pointer
// fp: frame pointer
__ LeaveExitFrame();
// check if we should retry or throw exception
Label retry;
__ bind(&failure_returned);
STATIC_ASSERT(Failure::RETRY_AFTER_GC == 0);
__ tst(r0, Operand(((1 << kFailureTypeTagSize) - 1) << kFailureTagSize));
__ b(eq, &retry);
// Special handling of out of memory exceptions.
Failure* out_of_memory = Failure::OutOfMemoryException();
__ cmp(r0, Operand(reinterpret_cast<int32_t>(out_of_memory)));
__ b(eq, throw_out_of_memory_exception);
// Retrieve the pending exception and clear the variable.
__ mov(ip, Operand(ExternalReference::the_hole_value_location()));
__ ldr(r3, MemOperand(ip));
__ mov(ip, Operand(ExternalReference(Top::k_pending_exception_address)));
__ ldr(r0, MemOperand(ip));
__ str(r3, MemOperand(ip));
// Special handling of termination exceptions which are uncatchable
// by javascript code.
__ cmp(r0, Operand(Factory::termination_exception()));
__ b(eq, throw_termination_exception);
// Handle normal exception.
__ jmp(throw_normal_exception);
__ bind(&retry); // pass last failure (r0) as parameter (r0) when retrying
}
void CEntryStub::Generate(MacroAssembler* masm) {
// Called from JavaScript; parameters are on stack as if calling JS function
// r0: number of arguments including receiver
// r1: pointer to builtin function
// fp: frame pointer (restored after C call)
// sp: stack pointer (restored as callee's sp after C call)
// cp: current context (C callee-saved)
// Result returned in r0 or r0+r1 by default.
// NOTE: Invocations of builtins may return failure objects
// instead of a proper result. The builtin entry handles
// this by performing a garbage collection and retrying the
// builtin once.
// Enter the exit frame that transitions from JavaScript to C++.
__ EnterExitFrame();
// r4: number of arguments (C callee-saved)
// r5: pointer to builtin function (C callee-saved)
// r6: pointer to first argument (C callee-saved)
Label throw_normal_exception;
Label throw_termination_exception;
Label throw_out_of_memory_exception;
// Call into the runtime system.
GenerateCore(masm,
&throw_normal_exception,
&throw_termination_exception,
&throw_out_of_memory_exception,
false,
false,
-kPointerSize);
// Do space-specific GC and retry runtime call.
GenerateCore(masm,
&throw_normal_exception,
&throw_termination_exception,
&throw_out_of_memory_exception,
true,
false,
0);
// Do full GC and retry runtime call one final time.
Failure* failure = Failure::InternalError();
__ mov(r0, Operand(reinterpret_cast<int32_t>(failure)));
GenerateCore(masm,
&throw_normal_exception,
&throw_termination_exception,
&throw_out_of_memory_exception,
true,
true,
kPointerSize);
__ bind(&throw_out_of_memory_exception);
GenerateThrowUncatchable(masm, OUT_OF_MEMORY);
__ bind(&throw_termination_exception);
GenerateThrowUncatchable(masm, TERMINATION);
__ bind(&throw_normal_exception);
GenerateThrowTOS(masm);
}
void JSEntryStub::GenerateBody(MacroAssembler* masm, bool is_construct) {
// r0: code entry
// r1: function
// r2: receiver
// r3: argc
// [sp+0]: argv
Label invoke, exit;
// Called from C, so do not pop argc and args on exit (preserve sp)
// No need to save register-passed args
// Save callee-saved registers (incl. cp and fp), sp, and lr
__ stm(db_w, sp, kCalleeSaved | lr.bit());
// Get address of argv, see stm above.
// r0: code entry
// r1: function
// r2: receiver
// r3: argc
__ ldr(r4, MemOperand(sp, (kNumCalleeSaved + 1) * kPointerSize)); // argv
// Push a frame with special values setup to mark it as an entry frame.
// r0: code entry
// r1: function
// r2: receiver
// r3: argc
// r4: argv
__ mov(r8, Operand(-1)); // Push a bad frame pointer to fail if it is used.
int marker = is_construct ? StackFrame::ENTRY_CONSTRUCT : StackFrame::ENTRY;
__ mov(r7, Operand(Smi::FromInt(marker)));
__ mov(r6, Operand(Smi::FromInt(marker)));
__ mov(r5, Operand(ExternalReference(Top::k_c_entry_fp_address)));
__ ldr(r5, MemOperand(r5));
__ Push(r8, r7, r6, r5);
// Setup frame pointer for the frame to be pushed.
__ add(fp, sp, Operand(-EntryFrameConstants::kCallerFPOffset));
// Call a faked try-block that does the invoke.
__ bl(&invoke);
// Caught exception: Store result (exception) in the pending
// exception field in the JSEnv and return a failure sentinel.
// Coming in here the fp will be invalid because the PushTryHandler below
// sets it to 0 to signal the existence of the JSEntry frame.
__ mov(ip, Operand(ExternalReference(Top::k_pending_exception_address)));
__ str(r0, MemOperand(ip));
__ mov(r0, Operand(reinterpret_cast<int32_t>(Failure::Exception())));
__ b(&exit);
// Invoke: Link this frame into the handler chain.
__ bind(&invoke);
// Must preserve r0-r4, r5-r7 are available.
__ PushTryHandler(IN_JS_ENTRY, JS_ENTRY_HANDLER);
// If an exception not caught by another handler occurs, this handler
// returns control to the code after the bl(&invoke) above, which
// restores all kCalleeSaved registers (including cp and fp) to their
// saved values before returning a failure to C.
// Clear any pending exceptions.
__ mov(ip, Operand(ExternalReference::the_hole_value_location()));
__ ldr(r5, MemOperand(ip));
__ mov(ip, Operand(ExternalReference(Top::k_pending_exception_address)));
__ str(r5, MemOperand(ip));
// Invoke the function by calling through JS entry trampoline builtin.
// Notice that we cannot store a reference to the trampoline code directly in
// this stub, because runtime stubs are not traversed when doing GC.
// Expected registers by Builtins::JSEntryTrampoline
// r0: code entry
// r1: function
// r2: receiver
// r3: argc
// r4: argv
if (is_construct) {
ExternalReference construct_entry(Builtins::JSConstructEntryTrampoline);
__ mov(ip, Operand(construct_entry));
} else {
ExternalReference entry(Builtins::JSEntryTrampoline);
__ mov(ip, Operand(entry));
}
__ ldr(ip, MemOperand(ip)); // deref address
// Branch and link to JSEntryTrampoline. We don't use the double underscore
// macro for the add instruction because we don't want the coverage tool
// inserting instructions here after we read the pc.
__ mov(lr, Operand(pc));
masm->add(pc, ip, Operand(Code::kHeaderSize - kHeapObjectTag));
// Unlink this frame from the handler chain. When reading the
// address of the next handler, there is no need to use the address
// displacement since the current stack pointer (sp) points directly
// to the stack handler.
__ ldr(r3, MemOperand(sp, StackHandlerConstants::kNextOffset));
__ mov(ip, Operand(ExternalReference(Top::k_handler_address)));
__ str(r3, MemOperand(ip));
// No need to restore registers
__ add(sp, sp, Operand(StackHandlerConstants::kSize));
__ bind(&exit); // r0 holds result
// Restore the top frame descriptors from the stack.
__ pop(r3);
__ mov(ip, Operand(ExternalReference(Top::k_c_entry_fp_address)));
__ str(r3, MemOperand(ip));
// Reset the stack to the callee saved registers.
__ add(sp, sp, Operand(-EntryFrameConstants::kCallerFPOffset));
// Restore callee-saved registers and return.
#ifdef DEBUG
if (FLAG_debug_code) {
__ mov(lr, Operand(pc));
}
#endif
__ ldm(ia_w, sp, kCalleeSaved | pc.bit());
}
// This stub performs an instanceof, calling the builtin function if
// necessary. Uses r1 for the object, r0 for the function that it may
// be an instance of (these are fetched from the stack).
void InstanceofStub::Generate(MacroAssembler* masm) {
// Get the object - slow case for smis (we may need to throw an exception
// depending on the rhs).
Label slow, loop, is_instance, is_not_instance;
__ ldr(r0, MemOperand(sp, 1 * kPointerSize));
__ BranchOnSmi(r0, &slow);
// Check that the left hand is a JS object and put map in r3.
__ CompareObjectType(r0, r3, r2, FIRST_JS_OBJECT_TYPE);
__ b(lt, &slow);
__ cmp(r2, Operand(LAST_JS_OBJECT_TYPE));
__ b(gt, &slow);
// Get the prototype of the function (r4 is result, r2 is scratch).
__ ldr(r1, MemOperand(sp, 0));
// r1 is function, r3 is map.
// Look up the function and the map in the instanceof cache.
Label miss;
__ LoadRoot(ip, Heap::kInstanceofCacheFunctionRootIndex);
__ cmp(r1, ip);
__ b(ne, &miss);
__ LoadRoot(ip, Heap::kInstanceofCacheMapRootIndex);
__ cmp(r3, ip);
__ b(ne, &miss);
__ LoadRoot(r0, Heap::kInstanceofCacheAnswerRootIndex);
__ pop();
__ pop();
__ mov(pc, Operand(lr));
__ bind(&miss);
__ TryGetFunctionPrototype(r1, r4, r2, &slow);
// Check that the function prototype is a JS object.
__ BranchOnSmi(r4, &slow);
__ CompareObjectType(r4, r5, r5, FIRST_JS_OBJECT_TYPE);
__ b(lt, &slow);
__ cmp(r5, Operand(LAST_JS_OBJECT_TYPE));
__ b(gt, &slow);
__ StoreRoot(r1, Heap::kInstanceofCacheFunctionRootIndex);
__ StoreRoot(r3, Heap::kInstanceofCacheMapRootIndex);
// Register mapping: r3 is object map and r4 is function prototype.
// Get prototype of object into r2.
__ ldr(r2, FieldMemOperand(r3, Map::kPrototypeOffset));
// Loop through the prototype chain looking for the function prototype.
__ bind(&loop);
__ cmp(r2, Operand(r4));
__ b(eq, &is_instance);
__ LoadRoot(ip, Heap::kNullValueRootIndex);
__ cmp(r2, ip);
__ b(eq, &is_not_instance);
__ ldr(r2, FieldMemOperand(r2, HeapObject::kMapOffset));
__ ldr(r2, FieldMemOperand(r2, Map::kPrototypeOffset));
__ jmp(&loop);
__ bind(&is_instance);
__ mov(r0, Operand(Smi::FromInt(0)));
__ StoreRoot(r0, Heap::kInstanceofCacheAnswerRootIndex);
__ pop();
__ pop();
__ mov(pc, Operand(lr)); // Return.
__ bind(&is_not_instance);
__ mov(r0, Operand(Smi::FromInt(1)));
__ StoreRoot(r0, Heap::kInstanceofCacheAnswerRootIndex);
__ pop();
__ pop();
__ mov(pc, Operand(lr)); // Return.
// Slow-case. Tail call builtin.
__ bind(&slow);
__ InvokeBuiltin(Builtins::INSTANCE_OF, JUMP_JS);
}
void ArgumentsAccessStub::GenerateReadElement(MacroAssembler* masm) {
// The displacement is the offset of the last parameter (if any)
// relative to the frame pointer.
static const int kDisplacement =
StandardFrameConstants::kCallerSPOffset - kPointerSize;
// Check that the key is a smi.
Label slow;
__ BranchOnNotSmi(r1, &slow);
// Check if the calling frame is an arguments adaptor frame.
Label adaptor;
__ ldr(r2, MemOperand(fp, StandardFrameConstants::kCallerFPOffset));
__ ldr(r3, MemOperand(r2, StandardFrameConstants::kContextOffset));
__ cmp(r3, Operand(Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR)));
__ b(eq, &adaptor);
// Check index against formal parameters count limit passed in
// through register r0. Use unsigned comparison to get negative
// check for free.
__ cmp(r1, r0);
__ b(cs, &slow);
// Read the argument from the stack and return it.
__ sub(r3, r0, r1);
__ add(r3, fp, Operand(r3, LSL, kPointerSizeLog2 - kSmiTagSize));
__ ldr(r0, MemOperand(r3, kDisplacement));
__ Jump(lr);
// Arguments adaptor case: Check index against actual arguments
// limit found in the arguments adaptor frame. Use unsigned
// comparison to get negative check for free.
__ bind(&adaptor);
__ ldr(r0, MemOperand(r2, ArgumentsAdaptorFrameConstants::kLengthOffset));
__ cmp(r1, r0);
__ b(cs, &slow);
// Read the argument from the adaptor frame and return it.
__ sub(r3, r0, r1);
__ add(r3, r2, Operand(r3, LSL, kPointerSizeLog2 - kSmiTagSize));
__ ldr(r0, MemOperand(r3, kDisplacement));
__ Jump(lr);
// Slow-case: Handle non-smi or out-of-bounds access to arguments
// by calling the runtime system.
__ bind(&slow);
__ push(r1);
__ TailCallRuntime(Runtime::kGetArgumentsProperty, 1, 1);
}
void ArgumentsAccessStub::GenerateNewObject(MacroAssembler* masm) {
// sp[0] : number of parameters
// sp[4] : receiver displacement
// sp[8] : function
// Check if the calling frame is an arguments adaptor frame.
Label adaptor_frame, try_allocate, runtime;
__ ldr(r2, MemOperand(fp, StandardFrameConstants::kCallerFPOffset));
__ ldr(r3, MemOperand(r2, StandardFrameConstants::kContextOffset));
__ cmp(r3, Operand(Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR)));
__ b(eq, &adaptor_frame);
// Get the length from the frame.
__ ldr(r1, MemOperand(sp, 0));
__ b(&try_allocate);
// Patch the arguments.length and the parameters pointer.
__ bind(&adaptor_frame);
__ ldr(r1, MemOperand(r2, ArgumentsAdaptorFrameConstants::kLengthOffset));
__ str(r1, MemOperand(sp, 0));
__ add(r3, r2, Operand(r1, LSL, kPointerSizeLog2 - kSmiTagSize));
__ add(r3, r3, Operand(StandardFrameConstants::kCallerSPOffset));
__ str(r3, MemOperand(sp, 1 * kPointerSize));
// Try the new space allocation. Start out with computing the size
// of the arguments object and the elements array in words.
Label add_arguments_object;
__ bind(&try_allocate);
__ cmp(r1, Operand(0));
__ b(eq, &add_arguments_object);
__ mov(r1, Operand(r1, LSR, kSmiTagSize));
__ add(r1, r1, Operand(FixedArray::kHeaderSize / kPointerSize));
__ bind(&add_arguments_object);
__ add(r1, r1, Operand(Heap::kArgumentsObjectSize / kPointerSize));
// Do the allocation of both objects in one go.
__ AllocateInNewSpace(
r1,
r0,
r2,
r3,
&runtime,
static_cast<AllocationFlags>(TAG_OBJECT | SIZE_IN_WORDS));
// Get the arguments boilerplate from the current (global) context.
int offset = Context::SlotOffset(Context::ARGUMENTS_BOILERPLATE_INDEX);
__ ldr(r4, MemOperand(cp, Context::SlotOffset(Context::GLOBAL_INDEX)));
__ ldr(r4, FieldMemOperand(r4, GlobalObject::kGlobalContextOffset));
__ ldr(r4, MemOperand(r4, offset));
// Copy the JS object part.
__ CopyFields(r0, r4, r3.bit(), JSObject::kHeaderSize / kPointerSize);
// Setup the callee in-object property.
STATIC_ASSERT(Heap::arguments_callee_index == 0);
__ ldr(r3, MemOperand(sp, 2 * kPointerSize));
__ str(r3, FieldMemOperand(r0, JSObject::kHeaderSize));
// Get the length (smi tagged) and set that as an in-object property too.
STATIC_ASSERT(Heap::arguments_length_index == 1);
__ ldr(r1, MemOperand(sp, 0 * kPointerSize));
__ str(r1, FieldMemOperand(r0, JSObject::kHeaderSize + kPointerSize));
// If there are no actual arguments, we're done.
Label done;
__ cmp(r1, Operand(0));
__ b(eq, &done);
// Get the parameters pointer from the stack.
__ ldr(r2, MemOperand(sp, 1 * kPointerSize));
// Setup the elements pointer in the allocated arguments object and
// initialize the header in the elements fixed array.
__ add(r4, r0, Operand(Heap::kArgumentsObjectSize));
__ str(r4, FieldMemOperand(r0, JSObject::kElementsOffset));
__ LoadRoot(r3, Heap::kFixedArrayMapRootIndex);
__ str(r3, FieldMemOperand(r4, FixedArray::kMapOffset));
__ str(r1, FieldMemOperand(r4, FixedArray::kLengthOffset));
__ mov(r1, Operand(r1, LSR, kSmiTagSize)); // Untag the length for the loop.
// Copy the fixed array slots.
Label loop;
// Setup r4 to point to the first array slot.
__ add(r4, r4, Operand(FixedArray::kHeaderSize - kHeapObjectTag));
__ bind(&loop);
// Pre-decrement r2 with kPointerSize on each iteration.
// Pre-decrement in order to skip receiver.
__ ldr(r3, MemOperand(r2, kPointerSize, NegPreIndex));
// Post-increment r4 with kPointerSize on each iteration.
__ str(r3, MemOperand(r4, kPointerSize, PostIndex));
__ sub(r1, r1, Operand(1));
__ cmp(r1, Operand(0));
__ b(ne, &loop);
// Return and remove the on-stack parameters.
__ bind(&done);
__ add(sp, sp, Operand(3 * kPointerSize));
__ Ret();
// Do the runtime call to allocate the arguments object.
__ bind(&runtime);
__ TailCallRuntime(Runtime::kNewArgumentsFast, 3, 1);
}
void RegExpExecStub::Generate(MacroAssembler* masm) {
// Just jump directly to runtime if native RegExp is not selected at compile
// time or if regexp entry in generated code is turned off runtime switch or
// at compilation.
#ifdef V8_INTERPRETED_REGEXP
__ TailCallRuntime(Runtime::kRegExpExec, 4, 1);
#else // V8_INTERPRETED_REGEXP
if (!FLAG_regexp_entry_native) {
__ TailCallRuntime(Runtime::kRegExpExec, 4, 1);
return;
}
// Stack frame on entry.
// sp[0]: last_match_info (expected JSArray)
// sp[4]: previous index
// sp[8]: subject string
// sp[12]: JSRegExp object
static const int kLastMatchInfoOffset = 0 * kPointerSize;
static const int kPreviousIndexOffset = 1 * kPointerSize;
static const int kSubjectOffset = 2 * kPointerSize;
static const int kJSRegExpOffset = 3 * kPointerSize;
Label runtime, invoke_regexp;
// Allocation of registers for this function. These are in callee save
// registers and will be preserved by the call to the native RegExp code, as
// this code is called using the normal C calling convention. When calling
// directly from generated code the native RegExp code will not do a GC and
// therefore the content of these registers are safe to use after the call.
Register subject = r4;
Register regexp_data = r5;
Register last_match_info_elements = r6;
// Ensure that a RegExp stack is allocated.
ExternalReference address_of_regexp_stack_memory_address =
ExternalReference::address_of_regexp_stack_memory_address();
ExternalReference address_of_regexp_stack_memory_size =
ExternalReference::address_of_regexp_stack_memory_size();
__ mov(r0, Operand(address_of_regexp_stack_memory_size));
__ ldr(r0, MemOperand(r0, 0));
__ tst(r0, Operand(r0));
__ b(eq, &runtime);
// Check that the first argument is a JSRegExp object.
__ ldr(r0, MemOperand(sp, kJSRegExpOffset));
STATIC_ASSERT(kSmiTag == 0);
__ tst(r0, Operand(kSmiTagMask));
__ b(eq, &runtime);
__ CompareObjectType(r0, r1, r1, JS_REGEXP_TYPE);
__ b(ne, &runtime);
// Check that the RegExp has been compiled (data contains a fixed array).
__ ldr(regexp_data, FieldMemOperand(r0, JSRegExp::kDataOffset));
if (FLAG_debug_code) {
__ tst(regexp_data, Operand(kSmiTagMask));
__ Check(nz, "Unexpected type for RegExp data, FixedArray expected");
__ CompareObjectType(regexp_data, r0, r0, FIXED_ARRAY_TYPE);
__ Check(eq, "Unexpected type for RegExp data, FixedArray expected");
}
// regexp_data: RegExp data (FixedArray)
// Check the type of the RegExp. Only continue if type is JSRegExp::IRREGEXP.
__ ldr(r0, FieldMemOperand(regexp_data, JSRegExp::kDataTagOffset));
__ cmp(r0, Operand(Smi::FromInt(JSRegExp::IRREGEXP)));
__ b(ne, &runtime);
// regexp_data: RegExp data (FixedArray)
// Check that the number of captures fit in the static offsets vector buffer.
__ ldr(r2,
FieldMemOperand(regexp_data, JSRegExp::kIrregexpCaptureCountOffset));
// Calculate number of capture registers (number_of_captures + 1) * 2. This
// uses the asumption that smis are 2 * their untagged value.
STATIC_ASSERT(kSmiTag == 0);
STATIC_ASSERT(kSmiTagSize + kSmiShiftSize == 1);
__ add(r2, r2, Operand(2)); // r2 was a smi.
// Check that the static offsets vector buffer is large enough.
__ cmp(r2, Operand(OffsetsVector::kStaticOffsetsVectorSize));
__ b(hi, &runtime);
// r2: Number of capture registers
// regexp_data: RegExp data (FixedArray)
// Check that the second argument is a string.
__ ldr(subject, MemOperand(sp, kSubjectOffset));
__ tst(subject, Operand(kSmiTagMask));
__ b(eq, &runtime);
Condition is_string = masm->IsObjectStringType(subject, r0);
__ b(NegateCondition(is_string), &runtime);
// Get the length of the string to r3.
__ ldr(r3, FieldMemOperand(subject, String::kLengthOffset));
// r2: Number of capture registers
// r3: Length of subject string as a smi
// subject: Subject string
// regexp_data: RegExp data (FixedArray)
// Check that the third argument is a positive smi less than the subject
// string length. A negative value will be greater (unsigned comparison).
__ ldr(r0, MemOperand(sp, kPreviousIndexOffset));
__ tst(r0, Operand(kSmiTagMask));
__ b(ne, &runtime);
__ cmp(r3, Operand(r0));
__ b(ls, &runtime);
// r2: Number of capture registers
// subject: Subject string
// regexp_data: RegExp data (FixedArray)
// Check that the fourth object is a JSArray object.
__ ldr(r0, MemOperand(sp, kLastMatchInfoOffset));
__ tst(r0, Operand(kSmiTagMask));
__ b(eq, &runtime);
__ CompareObjectType(r0, r1, r1, JS_ARRAY_TYPE);
__ b(ne, &runtime);
// Check that the JSArray is in fast case.
__ ldr(last_match_info_elements,
FieldMemOperand(r0, JSArray::kElementsOffset));
__ ldr(r0, FieldMemOperand(last_match_info_elements, HeapObject::kMapOffset));
__ LoadRoot(ip, Heap::kFixedArrayMapRootIndex);
__ cmp(r0, ip);
__ b(ne, &runtime);
// Check that the last match info has space for the capture registers and the
// additional information.
__ ldr(r0,
FieldMemOperand(last_match_info_elements, FixedArray::kLengthOffset));
__ add(r2, r2, Operand(RegExpImpl::kLastMatchOverhead));
__ cmp(r2, Operand(r0, ASR, kSmiTagSize));
__ b(gt, &runtime);
// subject: Subject string
// regexp_data: RegExp data (FixedArray)
// Check the representation and encoding of the subject string.
Label seq_string;
__ ldr(r0, FieldMemOperand(subject, HeapObject::kMapOffset));
__ ldrb(r0, FieldMemOperand(r0, Map::kInstanceTypeOffset));
// First check for flat string.
__ tst(r0, Operand(kIsNotStringMask | kStringRepresentationMask));
STATIC_ASSERT((kStringTag | kSeqStringTag) == 0);
__ b(eq, &seq_string);
// subject: Subject string
// regexp_data: RegExp data (FixedArray)
// Check for flat cons string.
// A flat cons string is a cons string where the second part is the empty
// string. In that case the subject string is just the first part of the cons
// string. Also in this case the first part of the cons string is known to be
// a sequential string or an external string.
STATIC_ASSERT(kExternalStringTag !=0);
STATIC_ASSERT((kConsStringTag & kExternalStringTag) == 0);
__ tst(r0, Operand(kIsNotStringMask | kExternalStringTag));
__ b(ne, &runtime);
__ ldr(r0, FieldMemOperand(subject, ConsString::kSecondOffset));
__ LoadRoot(r1, Heap::kEmptyStringRootIndex);
__ cmp(r0, r1);
__ b(ne, &runtime);
__ ldr(subject, FieldMemOperand(subject, ConsString::kFirstOffset));
__ ldr(r0, FieldMemOperand(subject, HeapObject::kMapOffset));
__ ldrb(r0, FieldMemOperand(r0, Map::kInstanceTypeOffset));
// Is first part a flat string?
STATIC_ASSERT(kSeqStringTag == 0);
__ tst(r0, Operand(kStringRepresentationMask));
__ b(nz, &runtime);
__ bind(&seq_string);
// subject: Subject string
// regexp_data: RegExp data (FixedArray)
// r0: Instance type of subject string
STATIC_ASSERT(4 == kAsciiStringTag);
STATIC_ASSERT(kTwoByteStringTag == 0);
// Find the code object based on the assumptions above.
__ and_(r0, r0, Operand(kStringEncodingMask));
__ mov(r3, Operand(r0, ASR, 2), SetCC);
__ ldr(r7, FieldMemOperand(regexp_data, JSRegExp::kDataAsciiCodeOffset), ne);
__ ldr(r7, FieldMemOperand(regexp_data, JSRegExp::kDataUC16CodeOffset), eq);
// Check that the irregexp code has been generated for the actual string
// encoding. If it has, the field contains a code object otherwise it contains
// the hole.
__ CompareObjectType(r7, r0, r0, CODE_TYPE);
__ b(ne, &runtime);
// r3: encoding of subject string (1 if ascii, 0 if two_byte);
// r7: code
// subject: Subject string
// regexp_data: RegExp data (FixedArray)
// Load used arguments before starting to push arguments for call to native
// RegExp code to avoid handling changing stack height.
__ ldr(r1, MemOperand(sp, kPreviousIndexOffset));
__ mov(r1, Operand(r1, ASR, kSmiTagSize));
// r1: previous index
// r3: encoding of subject string (1 if ascii, 0 if two_byte);
// r7: code
// subject: Subject string
// regexp_data: RegExp data (FixedArray)
// All checks done. Now push arguments for native regexp code.
__ IncrementCounter(&Counters::regexp_entry_native, 1, r0, r2);
static const int kRegExpExecuteArguments = 7;
__ push(lr);
__ PrepareCallCFunction(kRegExpExecuteArguments, r0);
// Argument 7 (sp[8]): Indicate that this is a direct call from JavaScript.
__ mov(r0, Operand(1));
__ str(r0, MemOperand(sp, 2 * kPointerSize));
// Argument 6 (sp[4]): Start (high end) of backtracking stack memory area.
__ mov(r0, Operand(address_of_regexp_stack_memory_address));
__ ldr(r0, MemOperand(r0, 0));
__ mov(r2, Operand(address_of_regexp_stack_memory_size));
__ ldr(r2, MemOperand(r2, 0));
__ add(r0, r0, Operand(r2));
__ str(r0, MemOperand(sp, 1 * kPointerSize));
// Argument 5 (sp[0]): static offsets vector buffer.
__ mov(r0, Operand(ExternalReference::address_of_static_offsets_vector()));
__ str(r0, MemOperand(sp, 0 * kPointerSize));
// For arguments 4 and 3 get string length, calculate start of string data and
// calculate the shift of the index (0 for ASCII and 1 for two byte).
__ ldr(r0, FieldMemOperand(subject, String::kLengthOffset));
__ mov(r0, Operand(r0, ASR, kSmiTagSize));
STATIC_ASSERT(SeqAsciiString::kHeaderSize == SeqTwoByteString::kHeaderSize);
__ add(r9, subject, Operand(SeqAsciiString::kHeaderSize - kHeapObjectTag));
__ eor(r3, r3, Operand(1));
// Argument 4 (r3): End of string data
// Argument 3 (r2): Start of string data
__ add(r2, r9, Operand(r1, LSL, r3));
__ add(r3, r9, Operand(r0, LSL, r3));
// Argument 2 (r1): Previous index.
// Already there
// Argument 1 (r0): Subject string.
__ mov(r0, subject);
// Locate the code entry and call it.
__ add(r7, r7, Operand(Code::kHeaderSize - kHeapObjectTag));
__ CallCFunction(r7, kRegExpExecuteArguments);
__ pop(lr);
// r0: result
// subject: subject string (callee saved)
// regexp_data: RegExp data (callee saved)
// last_match_info_elements: Last match info elements (callee saved)
// Check the result.
Label success;
__ cmp(r0, Operand(NativeRegExpMacroAssembler::SUCCESS));
__ b(eq, &success);
Label failure;
__ cmp(r0, Operand(NativeRegExpMacroAssembler::FAILURE));
__ b(eq, &failure);
__ cmp(r0, Operand(NativeRegExpMacroAssembler::EXCEPTION));
// If not exception it can only be retry. Handle that in the runtime system.
__ b(ne, &runtime);
// Result must now be exception. If there is no pending exception already a
// stack overflow (on the backtrack stack) was detected in RegExp code but
// haven't created the exception yet. Handle that in the runtime system.
// TODO(592): Rerunning the RegExp to get the stack overflow exception.
__ mov(r0, Operand(ExternalReference::the_hole_value_location()));
__ ldr(r0, MemOperand(r0, 0));
__ mov(r1, Operand(ExternalReference(Top::k_pending_exception_address)));
__ ldr(r1, MemOperand(r1, 0));
__ cmp(r0, r1);
__ b(eq, &runtime);
__ bind(&failure);
// For failure and exception return null.
__ mov(r0, Operand(Factory::null_value()));
__ add(sp, sp, Operand(4 * kPointerSize));
__ Ret();
// Process the result from the native regexp code.
__ bind(&success);
__ ldr(r1,
FieldMemOperand(regexp_data, JSRegExp::kIrregexpCaptureCountOffset));
// Calculate number of capture registers (number_of_captures + 1) * 2.
STATIC_ASSERT(kSmiTag == 0);
STATIC_ASSERT(kSmiTagSize + kSmiShiftSize == 1);
__ add(r1, r1, Operand(2)); // r1 was a smi.
// r1: number of capture registers
// r4: subject string
// Store the capture count.
__ mov(r2, Operand(r1, LSL, kSmiTagSize + kSmiShiftSize)); // To smi.
__ str(r2, FieldMemOperand(last_match_info_elements,
RegExpImpl::kLastCaptureCountOffset));
// Store last subject and last input.
__ mov(r3, last_match_info_elements); // Moved up to reduce latency.
__ str(subject,
FieldMemOperand(last_match_info_elements,
RegExpImpl::kLastSubjectOffset));
__ RecordWrite(r3, Operand(RegExpImpl::kLastSubjectOffset), r2, r7);
__ str(subject,
FieldMemOperand(last_match_info_elements,
RegExpImpl::kLastInputOffset));
__ mov(r3, last_match_info_elements);
__ RecordWrite(r3, Operand(RegExpImpl::kLastInputOffset), r2, r7);
// Get the static offsets vector filled by the native regexp code.
ExternalReference address_of_static_offsets_vector =
ExternalReference::address_of_static_offsets_vector();
__ mov(r2, Operand(address_of_static_offsets_vector));
// r1: number of capture registers
// r2: offsets vector
Label next_capture, done;
// Capture register counter starts from number of capture registers and
// counts down until wraping after zero.
__ add(r0,
last_match_info_elements,
Operand(RegExpImpl::kFirstCaptureOffset - kHeapObjectTag));
__ bind(&next_capture);
__ sub(r1, r1, Operand(1), SetCC);
__ b(mi, &done);
// Read the value from the static offsets vector buffer.
__ ldr(r3, MemOperand(r2, kPointerSize, PostIndex));
// Store the smi value in the last match info.
__ mov(r3, Operand(r3, LSL, kSmiTagSize));
__ str(r3, MemOperand(r0, kPointerSize, PostIndex));
__ jmp(&next_capture);
__ bind(&done);
// Return last match info.
__ ldr(r0, MemOperand(sp, kLastMatchInfoOffset));
__ add(sp, sp, Operand(4 * kPointerSize));
__ Ret();
// Do the runtime call to execute the regexp.
__ bind(&runtime);
__ TailCallRuntime(Runtime::kRegExpExec, 4, 1);
#endif // V8_INTERPRETED_REGEXP
}
void CallFunctionStub::Generate(MacroAssembler* masm) {
Label slow;
// If the receiver might be a value (string, number or boolean) check for this
// and box it if it is.
if (ReceiverMightBeValue()) {
// Get the receiver from the stack.
// function, receiver [, arguments]
Label receiver_is_value, receiver_is_js_object;
__ ldr(r1, MemOperand(sp, argc_ * kPointerSize));
// Check if receiver is a smi (which is a number value).
__ BranchOnSmi(r1, &receiver_is_value);
// Check if the receiver is a valid JS object.
__ CompareObjectType(r1, r2, r2, FIRST_JS_OBJECT_TYPE);
__ b(ge, &receiver_is_js_object);
// Call the runtime to box the value.
__ bind(&receiver_is_value);
__ EnterInternalFrame();
__ push(r1);
__ InvokeBuiltin(Builtins::TO_OBJECT, CALL_JS);
__ LeaveInternalFrame();
__ str(r0, MemOperand(sp, argc_ * kPointerSize));
__ bind(&receiver_is_js_object);
}
// Get the function to call from the stack.
// function, receiver [, arguments]
__ ldr(r1, MemOperand(sp, (argc_ + 1) * kPointerSize));
// Check that the function is really a JavaScript function.
// r1: pushed function (to be verified)
__ BranchOnSmi(r1, &slow);
// Get the map of the function object.
__ CompareObjectType(r1, r2, r2, JS_FUNCTION_TYPE);
__ b(ne, &slow);
// Fast-case: Invoke the function now.
// r1: pushed function
ParameterCount actual(argc_);
__ InvokeFunction(r1, actual, JUMP_FUNCTION);
// Slow-case: Non-function called.
__ bind(&slow);
// CALL_NON_FUNCTION expects the non-function callee as receiver (instead
// of the original receiver from the call site).
__ str(r1, MemOperand(sp, argc_ * kPointerSize));
__ mov(r0, Operand(argc_)); // Setup the number of arguments.
__ mov(r2, Operand(0));
__ GetBuiltinEntry(r3, Builtins::CALL_NON_FUNCTION);
__ Jump(Handle<Code>(Builtins::builtin(Builtins::ArgumentsAdaptorTrampoline)),
RelocInfo::CODE_TARGET);
}
// Unfortunately you have to run without snapshots to see most of these
// names in the profile since most compare stubs end up in the snapshot.
const char* CompareStub::GetName() {
ASSERT((lhs_.is(r0) && rhs_.is(r1)) ||
(lhs_.is(r1) && rhs_.is(r0)));
if (name_ != NULL) return name_;
const int kMaxNameLength = 100;
name_ = Bootstrapper::AllocateAutoDeletedArray(kMaxNameLength);
if (name_ == NULL) return "OOM";
const char* cc_name;
switch (cc_) {
case lt: cc_name = "LT"; break;
case gt: cc_name = "GT"; break;
case le: cc_name = "LE"; break;
case ge: cc_name = "GE"; break;
case eq: cc_name = "EQ"; break;
case ne: cc_name = "NE"; break;
default: cc_name = "UnknownCondition"; break;
}
const char* lhs_name = lhs_.is(r0) ? "_r0" : "_r1";
const char* rhs_name = rhs_.is(r0) ? "_r0" : "_r1";
const char* strict_name = "";
if (strict_ && (cc_ == eq || cc_ == ne)) {
strict_name = "_STRICT";
}
const char* never_nan_nan_name = "";
if (never_nan_nan_ && (cc_ == eq || cc_ == ne)) {
never_nan_nan_name = "_NO_NAN";
}
const char* include_number_compare_name = "";
if (!include_number_compare_) {
include_number_compare_name = "_NO_NUMBER";
}
OS::SNPrintF(Vector<char>(name_, kMaxNameLength),
"CompareStub_%s%s%s%s%s%s",
cc_name,
lhs_name,
rhs_name,
strict_name,
never_nan_nan_name,
include_number_compare_name);
return name_;
}
int CompareStub::MinorKey() {
// Encode the three parameters in a unique 16 bit value. To avoid duplicate
// stubs the never NaN NaN condition is only taken into account if the
// condition is equals.
ASSERT((static_cast<unsigned>(cc_) >> 28) < (1 << 12));
ASSERT((lhs_.is(r0) && rhs_.is(r1)) ||
(lhs_.is(r1) && rhs_.is(r0)));
return ConditionField::encode(static_cast<unsigned>(cc_) >> 28)
| RegisterField::encode(lhs_.is(r0))
| StrictField::encode(strict_)
| NeverNanNanField::encode(cc_ == eq ? never_nan_nan_ : false)
| IncludeNumberCompareField::encode(include_number_compare_);
}
// StringCharCodeAtGenerator
void StringCharCodeAtGenerator::GenerateFast(MacroAssembler* masm) {
Label flat_string;
Label ascii_string;
Label got_char_code;
// If the receiver is a smi trigger the non-string case.
__ BranchOnSmi(object_, receiver_not_string_);
// Fetch the instance type of the receiver into result register.
__ ldr(result_, FieldMemOperand(object_, HeapObject::kMapOffset));
__ ldrb(result_, FieldMemOperand(result_, Map::kInstanceTypeOffset));
// If the receiver is not a string trigger the non-string case.
__ tst(result_, Operand(kIsNotStringMask));
__ b(ne, receiver_not_string_);
// If the index is non-smi trigger the non-smi case.
__ BranchOnNotSmi(index_, &index_not_smi_);
// Put smi-tagged index into scratch register.
__ mov(scratch_, index_);
__ bind(&got_smi_index_);
// Check for index out of range.
__ ldr(ip, FieldMemOperand(object_, String::kLengthOffset));
__ cmp(ip, Operand(scratch_));
__ b(ls, index_out_of_range_);
// We need special handling for non-flat strings.
STATIC_ASSERT(kSeqStringTag == 0);
__ tst(result_, Operand(kStringRepresentationMask));
__ b(eq, &flat_string);
// Handle non-flat strings.
__ tst(result_, Operand(kIsConsStringMask));
__ b(eq, &call_runtime_);
// ConsString.
// Check whether the right hand side is the empty string (i.e. if
// this is really a flat string in a cons string). If that is not
// the case we would rather go to the runtime system now to flatten
// the string.
__ ldr(result_, FieldMemOperand(object_, ConsString::kSecondOffset));
__ LoadRoot(ip, Heap::kEmptyStringRootIndex);
__ cmp(result_, Operand(ip));
__ b(ne, &call_runtime_);
// Get the first of the two strings and load its instance type.
__ ldr(object_, FieldMemOperand(object_, ConsString::kFirstOffset));
__ ldr(result_, FieldMemOperand(object_, HeapObject::kMapOffset));
__ ldrb(result_, FieldMemOperand(result_, Map::kInstanceTypeOffset));
// If the first cons component is also non-flat, then go to runtime.
STATIC_ASSERT(kSeqStringTag == 0);
__ tst(result_, Operand(kStringRepresentationMask));
__ b(nz, &call_runtime_);
// Check for 1-byte or 2-byte string.
__ bind(&flat_string);
STATIC_ASSERT(kAsciiStringTag != 0);
__ tst(result_, Operand(kStringEncodingMask));
__ b(nz, &ascii_string);
// 2-byte string.
// Load the 2-byte character code into the result register. We can
// add without shifting since the smi tag size is the log2 of the
// number of bytes in a two-byte character.
STATIC_ASSERT(kSmiTag == 0 && kSmiTagSize == 1 && kSmiShiftSize == 0);
__ add(scratch_, object_, Operand(scratch_));
__ ldrh(result_, FieldMemOperand(scratch_, SeqTwoByteString::kHeaderSize));
__ jmp(&got_char_code);
// ASCII string.
// Load the byte into the result register.
__ bind(&ascii_string);
__ add(scratch_, object_, Operand(scratch_, LSR, kSmiTagSize));
__ ldrb(result_, FieldMemOperand(scratch_, SeqAsciiString::kHeaderSize));
__ bind(&got_char_code);
__ mov(result_, Operand(result_, LSL, kSmiTagSize));
__ bind(&exit_);
}
void StringCharCodeAtGenerator::GenerateSlow(
MacroAssembler* masm, const RuntimeCallHelper& call_helper) {
__ Abort("Unexpected fallthrough to CharCodeAt slow case");
// Index is not a smi.
__ bind(&index_not_smi_);
// If index is a heap number, try converting it to an integer.
__ CheckMap(index_,
scratch_,
Heap::kHeapNumberMapRootIndex,
index_not_number_,
true);
call_helper.BeforeCall(masm);
__ Push(object_, index_);
__ push(index_); // Consumed by runtime conversion function.
if (index_flags_ == STRING_INDEX_IS_NUMBER) {
__ CallRuntime(Runtime::kNumberToIntegerMapMinusZero, 1);
} else {
ASSERT(index_flags_ == STRING_INDEX_IS_ARRAY_INDEX);
// NumberToSmi discards numbers that are not exact integers.
__ CallRuntime(Runtime::kNumberToSmi, 1);
}
// Save the conversion result before the pop instructions below
// have a chance to overwrite it.
__ Move(scratch_, r0);
__ pop(index_);
__ pop(object_);
// Reload the instance type.
__ ldr(result_, FieldMemOperand(object_, HeapObject::kMapOffset));
__ ldrb(result_, FieldMemOperand(result_, Map::kInstanceTypeOffset));
call_helper.AfterCall(masm);
// If index is still not a smi, it must be out of range.
__ BranchOnNotSmi(scratch_, index_out_of_range_);
// Otherwise, return to the fast path.
__ jmp(&got_smi_index_);
// Call runtime. We get here when the receiver is a string and the
// index is a number, but the code of getting the actual character
// is too complex (e.g., when the string needs to be flattened).
__ bind(&call_runtime_);
call_helper.BeforeCall(masm);
__ Push(object_, index_);
__ CallRuntime(Runtime::kStringCharCodeAt, 2);
__ Move(result_, r0);
call_helper.AfterCall(masm);
__ jmp(&exit_);
__ Abort("Unexpected fallthrough from CharCodeAt slow case");
}
// -------------------------------------------------------------------------
// StringCharFromCodeGenerator
void StringCharFromCodeGenerator::GenerateFast(MacroAssembler* masm) {
// Fast case of Heap::LookupSingleCharacterStringFromCode.
STATIC_ASSERT(kSmiTag == 0);
STATIC_ASSERT(kSmiShiftSize == 0);
ASSERT(IsPowerOf2(String::kMaxAsciiCharCode + 1));
__ tst(code_,
Operand(kSmiTagMask |
((~String::kMaxAsciiCharCode) << kSmiTagSize)));
__ b(nz, &slow_case_);
__ LoadRoot(result_, Heap::kSingleCharacterStringCacheRootIndex);
// At this point code register contains smi tagged ascii char code.
STATIC_ASSERT(kSmiTag == 0);
__ add(result_, result_, Operand(code_, LSL, kPointerSizeLog2 - kSmiTagSize));
__ ldr(result_, FieldMemOperand(result_, FixedArray::kHeaderSize));
__ LoadRoot(ip, Heap::kUndefinedValueRootIndex);
__ cmp(result_, Operand(ip));
__ b(eq, &slow_case_);
__ bind(&exit_);
}
void StringCharFromCodeGenerator::GenerateSlow(
MacroAssembler* masm, const RuntimeCallHelper& call_helper) {
__ Abort("Unexpected fallthrough to CharFromCode slow case");
__ bind(&slow_case_);
call_helper.BeforeCall(masm);
__ push(code_);
__ CallRuntime(Runtime::kCharFromCode, 1);
__ Move(result_, r0);
call_helper.AfterCall(masm);
__ jmp(&exit_);
__ Abort("Unexpected fallthrough from CharFromCode slow case");
}
// -------------------------------------------------------------------------
// StringCharAtGenerator
void StringCharAtGenerator::GenerateFast(MacroAssembler* masm) {
char_code_at_generator_.GenerateFast(masm);
char_from_code_generator_.GenerateFast(masm);
}
void StringCharAtGenerator::GenerateSlow(
MacroAssembler* masm, const RuntimeCallHelper& call_helper) {
char_code_at_generator_.GenerateSlow(masm, call_helper);
char_from_code_generator_.GenerateSlow(masm, call_helper);
}
class StringHelper : public AllStatic {
public:
// Generate code for copying characters using a simple loop. This should only
// be used in places where the number of characters is small and the
// additional setup and checking in GenerateCopyCharactersLong adds too much
// overhead. Copying of overlapping regions is not supported.
// Dest register ends at the position after the last character written.
static void GenerateCopyCharacters(MacroAssembler* masm,
Register dest,
Register src,
Register count,
Register scratch,
bool ascii);
// Generate code for copying a large number of characters. This function
// is allowed to spend extra time setting up conditions to make copying
// faster. Copying of overlapping regions is not supported.
// Dest register ends at the position after the last character written.
static void GenerateCopyCharactersLong(MacroAssembler* masm,
Register dest,
Register src,
Register count,
Register scratch1,
Register scratch2,
Register scratch3,
Register scratch4,
Register scratch5,
int flags);
// Probe the symbol table for a two character string. If the string is
// not found by probing a jump to the label not_found is performed. This jump
// does not guarantee that the string is not in the symbol table. If the
// string is found the code falls through with the string in register r0.
// Contents of both c1 and c2 registers are modified. At the exit c1 is
// guaranteed to contain halfword with low and high bytes equal to
// initial contents of c1 and c2 respectively.
static void GenerateTwoCharacterSymbolTableProbe(MacroAssembler* masm,
Register c1,
Register c2,
Register scratch1,
Register scratch2,
Register scratch3,
Register scratch4,
Register scratch5,
Label* not_found);
// Generate string hash.
static void GenerateHashInit(MacroAssembler* masm,
Register hash,
Register character);
static void GenerateHashAddCharacter(MacroAssembler* masm,
Register hash,
Register character);
static void GenerateHashGetHash(MacroAssembler* masm,
Register hash);
private:
DISALLOW_IMPLICIT_CONSTRUCTORS(StringHelper);
};
void StringHelper::GenerateCopyCharacters(MacroAssembler* masm,
Register dest,
Register src,
Register count,
Register scratch,
bool ascii) {
Label loop;
Label done;
// This loop just copies one character at a time, as it is only used for very
// short strings.
if (!ascii) {
__ add(count, count, Operand(count), SetCC);
} else {
__ cmp(count, Operand(0));
}
__ b(eq, &done);
__ bind(&loop);
__ ldrb(scratch, MemOperand(src, 1, PostIndex));
// Perform sub between load and dependent store to get the load time to
// complete.
__ sub(count, count, Operand(1), SetCC);
__ strb(scratch, MemOperand(dest, 1, PostIndex));
// last iteration.
__ b(gt, &loop);
__ bind(&done);
}
enum CopyCharactersFlags {
COPY_ASCII = 1,
DEST_ALWAYS_ALIGNED = 2
};
void StringHelper::GenerateCopyCharactersLong(MacroAssembler* masm,
Register dest,
Register src,
Register count,
Register scratch1,
Register scratch2,
Register scratch3,
Register scratch4,
Register scratch5,
int flags) {
bool ascii = (flags & COPY_ASCII) != 0;
bool dest_always_aligned = (flags & DEST_ALWAYS_ALIGNED) != 0;
if (dest_always_aligned && FLAG_debug_code) {
// Check that destination is actually word aligned if the flag says
// that it is.
__ tst(dest, Operand(kPointerAlignmentMask));
__ Check(eq, "Destination of copy not aligned.");
}
const int kReadAlignment = 4;
const int kReadAlignmentMask = kReadAlignment - 1;
// Ensure that reading an entire aligned word containing the last character
// of a string will not read outside the allocated area (because we pad up
// to kObjectAlignment).
STATIC_ASSERT(kObjectAlignment >= kReadAlignment);
// Assumes word reads and writes are little endian.
// Nothing to do for zero characters.
Label done;
if (!ascii) {
__ add(count, count, Operand(count), SetCC);
} else {
__ cmp(count, Operand(0));
}
__ b(eq, &done);
// Assume that you cannot read (or write) unaligned.
Label byte_loop;
// Must copy at least eight bytes, otherwise just do it one byte at a time.
__ cmp(count, Operand(8));
__ add(count, dest, Operand(count));
Register limit = count; // Read until src equals this.
__ b(lt, &byte_loop);
if (!dest_always_aligned) {
// Align dest by byte copying. Copies between zero and three bytes.
__ and_(scratch4, dest, Operand(kReadAlignmentMask), SetCC);
Label dest_aligned;
__ b(eq, &dest_aligned);
__ cmp(scratch4, Operand(2));
__ ldrb(scratch1, MemOperand(src, 1, PostIndex));
__ ldrb(scratch2, MemOperand(src, 1, PostIndex), le);
__ ldrb(scratch3, MemOperand(src, 1, PostIndex), lt);
__ strb(scratch1, MemOperand(dest, 1, PostIndex));
__ strb(scratch2, MemOperand(dest, 1, PostIndex), le);
__ strb(scratch3, MemOperand(dest, 1, PostIndex), lt);
__ bind(&dest_aligned);
}
Label simple_loop;
__ sub(scratch4, dest, Operand(src));
__ and_(scratch4, scratch4, Operand(0x03), SetCC);
__ b(eq, &simple_loop);
// Shift register is number of bits in a source word that
// must be combined with bits in the next source word in order
// to create a destination word.
// Complex loop for src/dst that are not aligned the same way.
{
Label loop;
__ mov(scratch4, Operand(scratch4, LSL, 3));
Register left_shift = scratch4;
__ and_(src, src, Operand(~3)); // Round down to load previous word.
__ ldr(scratch1, MemOperand(src, 4, PostIndex));
// Store the "shift" most significant bits of scratch in the least
// signficant bits (i.e., shift down by (32-shift)).
__ rsb(scratch2, left_shift, Operand(32));
Register right_shift = scratch2;
__ mov(scratch1, Operand(scratch1, LSR, right_shift));
__ bind(&loop);
__ ldr(scratch3, MemOperand(src, 4, PostIndex));
__ sub(scratch5, limit, Operand(dest));
__ orr(scratch1, scratch1, Operand(scratch3, LSL, left_shift));
__ str(scratch1, MemOperand(dest, 4, PostIndex));
__ mov(scratch1, Operand(scratch3, LSR, right_shift));
// Loop if four or more bytes left to copy.
// Compare to eight, because we did the subtract before increasing dst.
__ sub(scratch5, scratch5, Operand(8), SetCC);
__ b(ge, &loop);
}
// There is now between zero and three bytes left to copy (negative that
// number is in scratch5), and between one and three bytes already read into
// scratch1 (eight times that number in scratch4). We may have read past
// the end of the string, but because objects are aligned, we have not read
// past the end of the object.
// Find the minimum of remaining characters to move and preloaded characters
// and write those as bytes.
__ add(scratch5, scratch5, Operand(4), SetCC);
__ b(eq, &done);
__ cmp(scratch4, Operand(scratch5, LSL, 3), ne);
// Move minimum of bytes read and bytes left to copy to scratch4.
__ mov(scratch5, Operand(scratch4, LSR, 3), LeaveCC, lt);
// Between one and three (value in scratch5) characters already read into
// scratch ready to write.
__ cmp(scratch5, Operand(2));
__ strb(scratch1, MemOperand(dest, 1, PostIndex));
__ mov(scratch1, Operand(scratch1, LSR, 8), LeaveCC, ge);
__ strb(scratch1, MemOperand(dest, 1, PostIndex), ge);
__ mov(scratch1, Operand(scratch1, LSR, 8), LeaveCC, gt);
__ strb(scratch1, MemOperand(dest, 1, PostIndex), gt);
// Copy any remaining bytes.
__ b(&byte_loop);
// Simple loop.
// Copy words from src to dst, until less than four bytes left.
// Both src and dest are word aligned.
__ bind(&simple_loop);
{
Label loop;
__ bind(&loop);
__ ldr(scratch1, MemOperand(src, 4, PostIndex));
__ sub(scratch3, limit, Operand(dest));
__ str(scratch1, MemOperand(dest, 4, PostIndex));
// Compare to 8, not 4, because we do the substraction before increasing
// dest.
__ cmp(scratch3, Operand(8));
__ b(ge, &loop);
}
// Copy bytes from src to dst until dst hits limit.
__ bind(&byte_loop);
__ cmp(dest, Operand(limit));
__ ldrb(scratch1, MemOperand(src, 1, PostIndex), lt);
__ b(ge, &done);
__ strb(scratch1, MemOperand(dest, 1, PostIndex));
__ b(&byte_loop);
__ bind(&done);
}
void StringHelper::GenerateTwoCharacterSymbolTableProbe(MacroAssembler* masm,
Register c1,
Register c2,
Register scratch1,
Register scratch2,
Register scratch3,
Register scratch4,
Register scratch5,
Label* not_found) {
// Register scratch3 is the general scratch register in this function.
Register scratch = scratch3;
// Make sure that both characters are not digits as such strings has a
// different hash algorithm. Don't try to look for these in the symbol table.
Label not_array_index;
__ sub(scratch, c1, Operand(static_cast<int>('0')));
__ cmp(scratch, Operand(static_cast<int>('9' - '0')));
__ b(hi, &not_array_index);
__ sub(scratch, c2, Operand(static_cast<int>('0')));
__ cmp(scratch, Operand(static_cast<int>('9' - '0')));
// If check failed combine both characters into single halfword.
// This is required by the contract of the method: code at the
// not_found branch expects this combination in c1 register
__ orr(c1, c1, Operand(c2, LSL, kBitsPerByte), LeaveCC, ls);
__ b(ls, not_found);
__ bind(&not_array_index);
// Calculate the two character string hash.
Register hash = scratch1;
StringHelper::GenerateHashInit(masm, hash, c1);
StringHelper::GenerateHashAddCharacter(masm, hash, c2);
StringHelper::GenerateHashGetHash(masm, hash);
// Collect the two characters in a register.
Register chars = c1;
__ orr(chars, chars, Operand(c2, LSL, kBitsPerByte));
// chars: two character string, char 1 in byte 0 and char 2 in byte 1.
// hash: hash of two character string.
// Load symbol table
// Load address of first element of the symbol table.
Register symbol_table = c2;
__ LoadRoot(symbol_table, Heap::kSymbolTableRootIndex);
// Load undefined value
Register undefined = scratch4;
__ LoadRoot(undefined, Heap::kUndefinedValueRootIndex);
// Calculate capacity mask from the symbol table capacity.
Register mask = scratch2;
__ ldr(mask, FieldMemOperand(symbol_table, SymbolTable::kCapacityOffset));
__ mov(mask, Operand(mask, ASR, 1));
__ sub(mask, mask, Operand(1));
// Calculate untagged address of the first element of the symbol table.
Register first_symbol_table_element = symbol_table;
__ add(first_symbol_table_element, symbol_table,
Operand(SymbolTable::kElementsStartOffset - kHeapObjectTag));
// Registers
// chars: two character string, char 1 in byte 0 and char 2 in byte 1.
// hash: hash of two character string
// mask: capacity mask
// first_symbol_table_element: address of the first element of
// the symbol table
// scratch: -
// Perform a number of probes in the symbol table.
static const int kProbes = 4;
Label found_in_symbol_table;
Label next_probe[kProbes];
for (int i = 0; i < kProbes; i++) {
Register candidate = scratch5; // Scratch register contains candidate.
// Calculate entry in symbol table.
if (i > 0) {
__ add(candidate, hash, Operand(SymbolTable::GetProbeOffset(i)));
} else {
__ mov(candidate, hash);
}
__ and_(candidate, candidate, Operand(mask));
// Load the entry from the symble table.
STATIC_ASSERT(SymbolTable::kEntrySize == 1);
__ ldr(candidate,
MemOperand(first_symbol_table_element,
candidate,
LSL,
kPointerSizeLog2));
// If entry is undefined no string with this hash can be found.
__ cmp(candidate, undefined);
__ b(eq, not_found);
// If length is not 2 the string is not a candidate.
__ ldr(scratch, FieldMemOperand(candidate, String::kLengthOffset));
__ cmp(scratch, Operand(Smi::FromInt(2)));
__ b(ne, &next_probe[i]);
// Check that the candidate is a non-external ascii string.
__ ldr(scratch, FieldMemOperand(candidate, HeapObject::kMapOffset));
__ ldrb(scratch, FieldMemOperand(scratch, Map::kInstanceTypeOffset));
__ JumpIfInstanceTypeIsNotSequentialAscii(scratch, scratch,
&next_probe[i]);
// Check if the two characters match.
// Assumes that word load is little endian.
__ ldrh(scratch, FieldMemOperand(candidate, SeqAsciiString::kHeaderSize));
__ cmp(chars, scratch);
__ b(eq, &found_in_symbol_table);
__ bind(&next_probe[i]);
}
// No matching 2 character string found by probing.
__ jmp(not_found);
// Scratch register contains result when we fall through to here.
Register result = scratch;
__ bind(&found_in_symbol_table);
__ Move(r0, result);
}
void StringHelper::GenerateHashInit(MacroAssembler* masm,
Register hash,
Register character) {
// hash = character + (character << 10);
__ add(hash, character, Operand(character, LSL, 10));
// hash ^= hash >> 6;
__ eor(hash, hash, Operand(hash, ASR, 6));
}
void StringHelper::GenerateHashAddCharacter(MacroAssembler* masm,
Register hash,
Register character) {
// hash += character;
__ add(hash, hash, Operand(character));
// hash += hash << 10;
__ add(hash, hash, Operand(hash, LSL, 10));
// hash ^= hash >> 6;
__ eor(hash, hash, Operand(hash, ASR, 6));
}
void StringHelper::GenerateHashGetHash(MacroAssembler* masm,
Register hash) {
// hash += hash << 3;
__ add(hash, hash, Operand(hash, LSL, 3));
// hash ^= hash >> 11;
__ eor(hash, hash, Operand(hash, ASR, 11));
// hash += hash << 15;
__ add(hash, hash, Operand(hash, LSL, 15), SetCC);
// if (hash == 0) hash = 27;
__ mov(hash, Operand(27), LeaveCC, nz);
}
void SubStringStub::Generate(MacroAssembler* masm) {
Label runtime;
// Stack frame on entry.
// lr: return address
// sp[0]: to
// sp[4]: from
// sp[8]: string
// This stub is called from the native-call %_SubString(...), so
// nothing can be assumed about the arguments. It is tested that:
// "string" is a sequential string,
// both "from" and "to" are smis, and
// 0 <= from <= to <= string.length.
// If any of these assumptions fail, we call the runtime system.
static const int kToOffset = 0 * kPointerSize;
static const int kFromOffset = 1 * kPointerSize;
static const int kStringOffset = 2 * kPointerSize;
// Check bounds and smi-ness.
__ ldr(r7, MemOperand(sp, kToOffset));
__ ldr(r6, MemOperand(sp, kFromOffset));
STATIC_ASSERT(kSmiTag == 0);
STATIC_ASSERT(kSmiTagSize + kSmiShiftSize == 1);
// I.e., arithmetic shift right by one un-smi-tags.
__ mov(r2, Operand(r7, ASR, 1), SetCC);
__ mov(r3, Operand(r6, ASR, 1), SetCC, cc);
// If either r2 or r6 had the smi tag bit set, then carry is set now.
__ b(cs, &runtime); // Either "from" or "to" is not a smi.
__ b(mi, &runtime); // From is negative.
__ sub(r2, r2, Operand(r3), SetCC);
__ b(mi, &runtime); // Fail if from > to.
// Special handling of sub-strings of length 1 and 2. One character strings
// are handled in the runtime system (looked up in the single character
// cache). Two character strings are looked for in the symbol cache.
__ cmp(r2, Operand(2));
__ b(lt, &runtime);
// r2: length
// r3: from index (untaged smi)
// r6: from (smi)
// r7: to (smi)
// Make sure first argument is a sequential (or flat) string.
__ ldr(r5, MemOperand(sp, kStringOffset));
STATIC_ASSERT(kSmiTag == 0);
__ tst(r5, Operand(kSmiTagMask));
__ b(eq, &runtime);
Condition is_string = masm->IsObjectStringType(r5, r1);
__ b(NegateCondition(is_string), &runtime);
// r1: instance type
// r2: length
// r3: from index (untaged smi)
// r5: string
// r6: from (smi)
// r7: to (smi)
Label seq_string;
__ and_(r4, r1, Operand(kStringRepresentationMask));
STATIC_ASSERT(kSeqStringTag < kConsStringTag);
STATIC_ASSERT(kConsStringTag < kExternalStringTag);
__ cmp(r4, Operand(kConsStringTag));
__ b(gt, &runtime); // External strings go to runtime.
__ b(lt, &seq_string); // Sequential strings are handled directly.
// Cons string. Try to recurse (once) on the first substring.
// (This adds a little more generality than necessary to handle flattened
// cons strings, but not much).
__ ldr(r5, FieldMemOperand(r5, ConsString::kFirstOffset));
__ ldr(r4, FieldMemOperand(r5, HeapObject::kMapOffset));
__ ldrb(r1, FieldMemOperand(r4, Map::kInstanceTypeOffset));
__ tst(r1, Operand(kStringRepresentationMask));
STATIC_ASSERT(kSeqStringTag == 0);
__ b(ne, &runtime); // Cons and External strings go to runtime.
// Definitly a sequential string.
__ bind(&seq_string);
// r1: instance type.
// r2: length
// r3: from index (untaged smi)
// r5: string
// r6: from (smi)
// r7: to (smi)
__ ldr(r4, FieldMemOperand(r5, String::kLengthOffset));
__ cmp(r4, Operand(r7));
__ b(lt, &runtime); // Fail if to > length.
// r1: instance type.
// r2: result string length.
// r3: from index (untaged smi)
// r5: string.
// r6: from offset (smi)
// Check for flat ascii string.
Label non_ascii_flat;
__ tst(r1, Operand(kStringEncodingMask));
STATIC_ASSERT(kTwoByteStringTag == 0);
__ b(eq, &non_ascii_flat);
Label result_longer_than_two;
__ cmp(r2, Operand(2));
__ b(gt, &result_longer_than_two);
// Sub string of length 2 requested.
// Get the two characters forming the sub string.
__ add(r5, r5, Operand(r3));
__ ldrb(r3, FieldMemOperand(r5, SeqAsciiString::kHeaderSize));
__ ldrb(r4, FieldMemOperand(r5, SeqAsciiString::kHeaderSize + 1));
// Try to lookup two character string in symbol table.
Label make_two_character_string;
StringHelper::GenerateTwoCharacterSymbolTableProbe(
masm, r3, r4, r1, r5, r6, r7, r9, &make_two_character_string);
__ IncrementCounter(&Counters::sub_string_native, 1, r3, r4);
__ add(sp, sp, Operand(3 * kPointerSize));
__ Ret();
// r2: result string length.
// r3: two characters combined into halfword in little endian byte order.
__ bind(&make_two_character_string);
__ AllocateAsciiString(r0, r2, r4, r5, r9, &runtime);
__ strh(r3, FieldMemOperand(r0, SeqAsciiString::kHeaderSize));
__ IncrementCounter(&Counters::sub_string_native, 1, r3, r4);
__ add(sp, sp, Operand(3 * kPointerSize));
__ Ret();
__ bind(&result_longer_than_two);
// Allocate the result.
__ AllocateAsciiString(r0, r2, r3, r4, r1, &runtime);
// r0: result string.
// r2: result string length.
// r5: string.
// r6: from offset (smi)
// Locate first character of result.
__ add(r1, r0, Operand(SeqAsciiString::kHeaderSize - kHeapObjectTag));
// Locate 'from' character of string.
__ add(r5, r5, Operand(SeqAsciiString::kHeaderSize - kHeapObjectTag));
__ add(r5, r5, Operand(r6, ASR, 1));
// r0: result string.
// r1: first character of result string.
// r2: result string length.
// r5: first character of sub string to copy.
STATIC_ASSERT((SeqAsciiString::kHeaderSize & kObjectAlignmentMask) == 0);
StringHelper::GenerateCopyCharactersLong(masm, r1, r5, r2, r3, r4, r6, r7, r9,
COPY_ASCII | DEST_ALWAYS_ALIGNED);
__ IncrementCounter(&Counters::sub_string_native, 1, r3, r4);
__ add(sp, sp, Operand(3 * kPointerSize));
__ Ret();
__ bind(&non_ascii_flat);
// r2: result string length.
// r5: string.
// r6: from offset (smi)
// Check for flat two byte string.
// Allocate the result.
__ AllocateTwoByteString(r0, r2, r1, r3, r4, &runtime);
// r0: result string.
// r2: result string length.
// r5: string.
// Locate first character of result.
__ add(r1, r0, Operand(SeqTwoByteString::kHeaderSize - kHeapObjectTag));
// Locate 'from' character of string.
__ add(r5, r5, Operand(SeqTwoByteString::kHeaderSize - kHeapObjectTag));
// As "from" is a smi it is 2 times the value which matches the size of a two
// byte character.
__ add(r5, r5, Operand(r6));
// r0: result string.
// r1: first character of result.
// r2: result length.
// r5: first character of string to copy.
STATIC_ASSERT((SeqTwoByteString::kHeaderSize & kObjectAlignmentMask) == 0);
StringHelper::GenerateCopyCharactersLong(masm, r1, r5, r2, r3, r4, r6, r7, r9,
DEST_ALWAYS_ALIGNED);
__ IncrementCounter(&Counters::sub_string_native, 1, r3, r4);
__ add(sp, sp, Operand(3 * kPointerSize));
__ Ret();
// Just jump to runtime to create the sub string.
__ bind(&runtime);
__ TailCallRuntime(Runtime::kSubString, 3, 1);
}
void StringCompareStub::GenerateCompareFlatAsciiStrings(MacroAssembler* masm,
Register left,
Register right,
Register scratch1,
Register scratch2,
Register scratch3,
Register scratch4) {
Label compare_lengths;
// Find minimum length and length difference.
__ ldr(scratch1, FieldMemOperand(left, String::kLengthOffset));
__ ldr(scratch2, FieldMemOperand(right, String::kLengthOffset));
__ sub(scratch3, scratch1, Operand(scratch2), SetCC);
Register length_delta = scratch3;
__ mov(scratch1, scratch2, LeaveCC, gt);
Register min_length = scratch1;
STATIC_ASSERT(kSmiTag == 0);
__ tst(min_length, Operand(min_length));
__ b(eq, &compare_lengths);
// Untag smi.
__ mov(min_length, Operand(min_length, ASR, kSmiTagSize));
// Setup registers so that we only need to increment one register
// in the loop.
__ add(scratch2, min_length,
Operand(SeqAsciiString::kHeaderSize - kHeapObjectTag));
__ add(left, left, Operand(scratch2));
__ add(right, right, Operand(scratch2));
// Registers left and right points to the min_length character of strings.
__ rsb(min_length, min_length, Operand(-1));
Register index = min_length;
// Index starts at -min_length.
{
// Compare loop.
Label loop;
__ bind(&loop);
// Compare characters.
__ add(index, index, Operand(1), SetCC);
__ ldrb(scratch2, MemOperand(left, index), ne);
__ ldrb(scratch4, MemOperand(right, index), ne);
// Skip to compare lengths with eq condition true.
__ b(eq, &compare_lengths);
__ cmp(scratch2, scratch4);
__ b(eq, &loop);
// Fallthrough with eq condition false.
}
// Compare lengths - strings up to min-length are equal.
__ bind(&compare_lengths);
ASSERT(Smi::FromInt(EQUAL) == static_cast<Smi*>(0));
// Use zero length_delta as result.
__ mov(r0, Operand(length_delta), SetCC, eq);
// Fall through to here if characters compare not-equal.
__ mov(r0, Operand(Smi::FromInt(GREATER)), LeaveCC, gt);
__ mov(r0, Operand(Smi::FromInt(LESS)), LeaveCC, lt);
__ Ret();
}
void StringCompareStub::Generate(MacroAssembler* masm) {
Label runtime;
// Stack frame on entry.
// sp[0]: right string
// sp[4]: left string
__ ldr(r0, MemOperand(sp, 1 * kPointerSize)); // left
__ ldr(r1, MemOperand(sp, 0 * kPointerSize)); // right
Label not_same;
__ cmp(r0, r1);
__ b(ne, &not_same);
STATIC_ASSERT(EQUAL == 0);
STATIC_ASSERT(kSmiTag == 0);
__ mov(r0, Operand(Smi::FromInt(EQUAL)));
__ IncrementCounter(&Counters::string_compare_native, 1, r1, r2);
__ add(sp, sp, Operand(2 * kPointerSize));
__ Ret();
__ bind(&not_same);
// Check that both objects are sequential ascii strings.
__ JumpIfNotBothSequentialAsciiStrings(r0, r1, r2, r3, &runtime);
// Compare flat ascii strings natively. Remove arguments from stack first.
__ IncrementCounter(&Counters::string_compare_native, 1, r2, r3);
__ add(sp, sp, Operand(2 * kPointerSize));
GenerateCompareFlatAsciiStrings(masm, r0, r1, r2, r3, r4, r5);
// Call the runtime; it returns -1 (less), 0 (equal), or 1 (greater)
// tagged as a small integer.
__ bind(&runtime);
__ TailCallRuntime(Runtime::kStringCompare, 2, 1);
}
void StringAddStub::Generate(MacroAssembler* masm) {
Label string_add_runtime;
// Stack on entry:
// sp[0]: second argument.
// sp[4]: first argument.
// Load the two arguments.
__ ldr(r0, MemOperand(sp, 1 * kPointerSize)); // First argument.
__ ldr(r1, MemOperand(sp, 0 * kPointerSize)); // Second argument.
// Make sure that both arguments are strings if not known in advance.
if (string_check_) {
STATIC_ASSERT(kSmiTag == 0);
__ JumpIfEitherSmi(r0, r1, &string_add_runtime);
// Load instance types.
__ ldr(r4, FieldMemOperand(r0, HeapObject::kMapOffset));
__ ldr(r5, FieldMemOperand(r1, HeapObject::kMapOffset));
__ ldrb(r4, FieldMemOperand(r4, Map::kInstanceTypeOffset));
__ ldrb(r5, FieldMemOperand(r5, Map::kInstanceTypeOffset));
STATIC_ASSERT(kStringTag == 0);
// If either is not a string, go to runtime.
__ tst(r4, Operand(kIsNotStringMask));
__ tst(r5, Operand(kIsNotStringMask), eq);
__ b(ne, &string_add_runtime);
}
// Both arguments are strings.
// r0: first string
// r1: second string
// r4: first string instance type (if string_check_)
// r5: second string instance type (if string_check_)
{
Label strings_not_empty;
// Check if either of the strings are empty. In that case return the other.
__ ldr(r2, FieldMemOperand(r0, String::kLengthOffset));
__ ldr(r3, FieldMemOperand(r1, String::kLengthOffset));
STATIC_ASSERT(kSmiTag == 0);
__ cmp(r2, Operand(Smi::FromInt(0))); // Test if first string is empty.
__ mov(r0, Operand(r1), LeaveCC, eq); // If first is empty, return second.
STATIC_ASSERT(kSmiTag == 0);
// Else test if second string is empty.
__ cmp(r3, Operand(Smi::FromInt(0)), ne);
__ b(ne, &strings_not_empty); // If either string was empty, return r0.
__ IncrementCounter(&Counters::string_add_native, 1, r2, r3);
__ add(sp, sp, Operand(2 * kPointerSize));
__ Ret();
__ bind(&strings_not_empty);
}
__ mov(r2, Operand(r2, ASR, kSmiTagSize));
__ mov(r3, Operand(r3, ASR, kSmiTagSize));
// Both strings are non-empty.
// r0: first string
// r1: second string
// r2: length of first string
// r3: length of second string
// r4: first string instance type (if string_check_)
// r5: second string instance type (if string_check_)
// Look at the length of the result of adding the two strings.
Label string_add_flat_result, longer_than_two;
// Adding two lengths can't overflow.
STATIC_ASSERT(String::kMaxLength < String::kMaxLength * 2);
__ add(r6, r2, Operand(r3));
// Use the runtime system when adding two one character strings, as it
// contains optimizations for this specific case using the symbol table.
__ cmp(r6, Operand(2));
__ b(ne, &longer_than_two);
// Check that both strings are non-external ascii strings.
if (!string_check_) {
__ ldr(r4, FieldMemOperand(r0, HeapObject::kMapOffset));
__ ldr(r5, FieldMemOperand(r1, HeapObject::kMapOffset));
__ ldrb(r4, FieldMemOperand(r4, Map::kInstanceTypeOffset));
__ ldrb(r5, FieldMemOperand(r5, Map::kInstanceTypeOffset));
}
__ JumpIfBothInstanceTypesAreNotSequentialAscii(r4, r5, r6, r7,
&string_add_runtime);
// Get the two characters forming the sub string.
__ ldrb(r2, FieldMemOperand(r0, SeqAsciiString::kHeaderSize));
__ ldrb(r3, FieldMemOperand(r1, SeqAsciiString::kHeaderSize));
// Try to lookup two character string in symbol table. If it is not found
// just allocate a new one.
Label make_two_character_string;
StringHelper::GenerateTwoCharacterSymbolTableProbe(
masm, r2, r3, r6, r7, r4, r5, r9, &make_two_character_string);
__ IncrementCounter(&Counters::string_add_native, 1, r2, r3);
__ add(sp, sp, Operand(2 * kPointerSize));
__ Ret();
__ bind(&make_two_character_string);
// Resulting string has length 2 and first chars of two strings
// are combined into single halfword in r2 register.
// So we can fill resulting string without two loops by a single
// halfword store instruction (which assumes that processor is
// in a little endian mode)
__ mov(r6, Operand(2));
__ AllocateAsciiString(r0, r6, r4, r5, r9, &string_add_runtime);
__ strh(r2, FieldMemOperand(r0, SeqAsciiString::kHeaderSize));
__ IncrementCounter(&Counters::string_add_native, 1, r2, r3);
__ add(sp, sp, Operand(2 * kPointerSize));
__ Ret();
__ bind(&longer_than_two);
// Check if resulting string will be flat.
__ cmp(r6, Operand(String::kMinNonFlatLength));
__ b(lt, &string_add_flat_result);
// Handle exceptionally long strings in the runtime system.
STATIC_ASSERT((String::kMaxLength & 0x80000000) == 0);
ASSERT(IsPowerOf2(String::kMaxLength + 1));
// kMaxLength + 1 is representable as shifted literal, kMaxLength is not.
__ cmp(r6, Operand(String::kMaxLength + 1));
__ b(hs, &string_add_runtime);
// If result is not supposed to be flat, allocate a cons string object.
// If both strings are ascii the result is an ascii cons string.
if (!string_check_) {
__ ldr(r4, FieldMemOperand(r0, HeapObject::kMapOffset));
__ ldr(r5, FieldMemOperand(r1, HeapObject::kMapOffset));
__ ldrb(r4, FieldMemOperand(r4, Map::kInstanceTypeOffset));
__ ldrb(r5, FieldMemOperand(r5, Map::kInstanceTypeOffset));
}
Label non_ascii, allocated, ascii_data;
STATIC_ASSERT(kTwoByteStringTag == 0);
__ tst(r4, Operand(kStringEncodingMask));
__ tst(r5, Operand(kStringEncodingMask), ne);
__ b(eq, &non_ascii);
// Allocate an ASCII cons string.
__ bind(&ascii_data);
__ AllocateAsciiConsString(r7, r6, r4, r5, &string_add_runtime);
__ bind(&allocated);
// Fill the fields of the cons string.
__ str(r0, FieldMemOperand(r7, ConsString::kFirstOffset));
__ str(r1, FieldMemOperand(r7, ConsString::kSecondOffset));
__ mov(r0, Operand(r7));
__ IncrementCounter(&Counters::string_add_native, 1, r2, r3);
__ add(sp, sp, Operand(2 * kPointerSize));
__ Ret();
__ bind(&non_ascii);
// At least one of the strings is two-byte. Check whether it happens
// to contain only ascii characters.
// r4: first instance type.
// r5: second instance type.
__ tst(r4, Operand(kAsciiDataHintMask));
__ tst(r5, Operand(kAsciiDataHintMask), ne);
__ b(ne, &ascii_data);
__ eor(r4, r4, Operand(r5));
STATIC_ASSERT(kAsciiStringTag != 0 && kAsciiDataHintTag != 0);
__ and_(r4, r4, Operand(kAsciiStringTag | kAsciiDataHintTag));
__ cmp(r4, Operand(kAsciiStringTag | kAsciiDataHintTag));
__ b(eq, &ascii_data);
// Allocate a two byte cons string.
__ AllocateTwoByteConsString(r7, r6, r4, r5, &string_add_runtime);
__ jmp(&allocated);
// Handle creating a flat result. First check that both strings are
// sequential and that they have the same encoding.
// r0: first string
// r1: second string
// r2: length of first string
// r3: length of second string
// r4: first string instance type (if string_check_)
// r5: second string instance type (if string_check_)
// r6: sum of lengths.
__ bind(&string_add_flat_result);
if (!string_check_) {
__ ldr(r4, FieldMemOperand(r0, HeapObject::kMapOffset));
__ ldr(r5, FieldMemOperand(r1, HeapObject::kMapOffset));
__ ldrb(r4, FieldMemOperand(r4, Map::kInstanceTypeOffset));
__ ldrb(r5, FieldMemOperand(r5, Map::kInstanceTypeOffset));
}
// Check that both strings are sequential.
STATIC_ASSERT(kSeqStringTag == 0);
__ tst(r4, Operand(kStringRepresentationMask));
__ tst(r5, Operand(kStringRepresentationMask), eq);
__ b(ne, &string_add_runtime);
// Now check if both strings have the same encoding (ASCII/Two-byte).
// r0: first string.
// r1: second string.
// r2: length of first string.
// r3: length of second string.
// r6: sum of lengths..
Label non_ascii_string_add_flat_result;
ASSERT(IsPowerOf2(kStringEncodingMask)); // Just one bit to test.
__ eor(r7, r4, Operand(r5));
__ tst(r7, Operand(kStringEncodingMask));
__ b(ne, &string_add_runtime);
// And see if it's ASCII or two-byte.
__ tst(r4, Operand(kStringEncodingMask));
__ b(eq, &non_ascii_string_add_flat_result);
// Both strings are sequential ASCII strings. We also know that they are
// short (since the sum of the lengths is less than kMinNonFlatLength).
// r6: length of resulting flat string
__ AllocateAsciiString(r7, r6, r4, r5, r9, &string_add_runtime);
// Locate first character of result.
__ add(r6, r7, Operand(SeqAsciiString::kHeaderSize - kHeapObjectTag));
// Locate first character of first argument.
__ add(r0, r0, Operand(SeqAsciiString::kHeaderSize - kHeapObjectTag));
// r0: first character of first string.
// r1: second string.
// r2: length of first string.
// r3: length of second string.
// r6: first character of result.
// r7: result string.
StringHelper::GenerateCopyCharacters(masm, r6, r0, r2, r4, true);
// Load second argument and locate first character.
__ add(r1, r1, Operand(SeqAsciiString::kHeaderSize - kHeapObjectTag));
// r1: first character of second string.
// r3: length of second string.
// r6: next character of result.
// r7: result string.
StringHelper::GenerateCopyCharacters(masm, r6, r1, r3, r4, true);
__ mov(r0, Operand(r7));
__ IncrementCounter(&Counters::string_add_native, 1, r2, r3);
__ add(sp, sp, Operand(2 * kPointerSize));
__ Ret();
__ bind(&non_ascii_string_add_flat_result);
// Both strings are sequential two byte strings.
// r0: first string.
// r1: second string.
// r2: length of first string.
// r3: length of second string.
// r6: sum of length of strings.
__ AllocateTwoByteString(r7, r6, r4, r5, r9, &string_add_runtime);
// r0: first string.
// r1: second string.
// r2: length of first string.
// r3: length of second string.
// r7: result string.
// Locate first character of result.
__ add(r6, r7, Operand(SeqTwoByteString::kHeaderSize - kHeapObjectTag));
// Locate first character of first argument.
__ add(r0, r0, Operand(SeqTwoByteString::kHeaderSize - kHeapObjectTag));
// r0: first character of first string.
// r1: second string.
// r2: length of first string.
// r3: length of second string.
// r6: first character of result.
// r7: result string.
StringHelper::GenerateCopyCharacters(masm, r6, r0, r2, r4, false);
// Locate first character of second argument.
__ add(r1, r1, Operand(SeqTwoByteString::kHeaderSize - kHeapObjectTag));
// r1: first character of second string.
// r3: length of second string.
// r6: next character of result (after copy of first string).
// r7: result string.
StringHelper::GenerateCopyCharacters(masm, r6, r1, r3, r4, false);
__ mov(r0, Operand(r7));
__ IncrementCounter(&Counters::string_add_native, 1, r2, r3);
__ add(sp, sp, Operand(2 * kPointerSize));
__ Ret();
// Just jump to runtime to add the two strings.
__ bind(&string_add_runtime);
__ TailCallRuntime(Runtime::kStringAdd, 2, 1);
}
#undef __
} } // namespace v8::internal
#endif // V8_TARGET_ARCH_ARM