src/ia32/codegen-ia32.cc - platform/external/v8 - Git at Google

 // Copyright 2011 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_IA32)

 #include "codegen.h"

 namespace v8 {
 namespace internal {


 // -------------------------------------------------------------------------
 // Platform-specific RuntimeCallHelper functions.

 void StubRuntimeCallHelper::BeforeCall(MacroAssembler* masm) const {
   masm->EnterInternalFrame();
 }


 void StubRuntimeCallHelper::AfterCall(MacroAssembler* masm) const {
   masm->LeaveInternalFrame();
 }


 #define __ masm.

 static void MemCopyWrapper(void* dest, const void* src, size_t size) {
   memcpy(dest, src, size);
 }


 OS::MemCopyFunction CreateMemCopyFunction() {
   size_t actual_size;
   // Allocate buffer in executable space.
   byte* buffer = static_cast<byte*>(OS::Allocate(1 * KB,
                                                  &actual_size,
                                                  true));
   if (buffer == NULL) return &MemCopyWrapper;
   MacroAssembler masm(NULL, buffer, static_cast<int>(actual_size));

   // Generated code is put into a fixed, unmovable, buffer, and not into
   // the V8 heap. We can't, and don't, refer to any relocatable addresses
   // (e.g. the JavaScript nan-object).

   // 32-bit C declaration function calls pass arguments on stack.

   // Stack layout:
   // esp[12]: Third argument, size.
   // esp[8]: Second argument, source pointer.
   // esp[4]: First argument, destination pointer.
   // esp[0]: return address

   const int kDestinationOffset = 1 * kPointerSize;
   const int kSourceOffset = 2 * kPointerSize;
   const int kSizeOffset = 3 * kPointerSize;

   int stack_offset = 0;  // Update if we change the stack height.

   if (FLAG_debug_code) {
     __ cmp(Operand(esp, kSizeOffset + stack_offset),
            Immediate(OS::kMinComplexMemCopy));
     Label ok;
     __ j(greater_equal, &ok);
     __ int3();
     __ bind(&ok);
   }
   if (CpuFeatures::IsSupported(SSE2)) {
     CpuFeatures::Scope enable(SSE2);
     __ push(edi);
     __ push(esi);
     stack_offset += 2 * kPointerSize;
     Register dst = edi;
     Register src = esi;
     Register count = ecx;
     __ mov(dst, Operand(esp, stack_offset + kDestinationOffset));
     __ mov(src, Operand(esp, stack_offset + kSourceOffset));
     __ mov(count, Operand(esp, stack_offset + kSizeOffset));


     __ movdqu(xmm0, Operand(src, 0));
     __ movdqu(Operand(dst, 0), xmm0);
     __ mov(edx, dst);
     __ and_(edx, 0xF);
     __ neg(edx);
     __ add(Operand(edx), Immediate(16));
     __ add(dst, Operand(edx));
     __ add(src, Operand(edx));
     __ sub(Operand(count), edx);

     // edi is now aligned. Check if esi is also aligned.
     Label unaligned_source;
     __ test(Operand(src), Immediate(0x0F));
     __ j(not_zero, &unaligned_source);
     {
       // Copy loop for aligned source and destination.
       __ mov(edx, count);
       Register loop_count = ecx;
       Register count = edx;
       __ shr(loop_count, 5);
       {
         // Main copy loop.
         Label loop;
         __ bind(&loop);
         __ prefetch(Operand(src, 0x20), 1);
         __ movdqa(xmm0, Operand(src, 0x00));
         __ movdqa(xmm1, Operand(src, 0x10));
         __ add(Operand(src), Immediate(0x20));

         __ movdqa(Operand(dst, 0x00), xmm0);
         __ movdqa(Operand(dst, 0x10), xmm1);
         __ add(Operand(dst), Immediate(0x20));

         __ dec(loop_count);
         __ j(not_zero, &loop);
       }

       // At most 31 bytes to copy.
       Label move_less_16;
       __ test(Operand(count), Immediate(0x10));
       __ j(zero, &move_less_16);
       __ movdqa(xmm0, Operand(src, 0));
       __ add(Operand(src), Immediate(0x10));
       __ movdqa(Operand(dst, 0), xmm0);
       __ add(Operand(dst), Immediate(0x10));
       __ bind(&move_less_16);

       // At most 15 bytes to copy. Copy 16 bytes at end of string.
       __ and_(count, 0xF);
       __ movdqu(xmm0, Operand(src, count, times_1, -0x10));
       __ movdqu(Operand(dst, count, times_1, -0x10), xmm0);

       __ mov(eax, Operand(esp, stack_offset + kDestinationOffset));
       __ pop(esi);
       __ pop(edi);
       __ ret(0);
     }
     __ Align(16);
     {
       // Copy loop for unaligned source and aligned destination.
       // If source is not aligned, we can't read it as efficiently.
       __ bind(&unaligned_source);
       __ mov(edx, ecx);
       Register loop_count = ecx;
       Register count = edx;
       __ shr(loop_count, 5);
       {
         // Main copy loop
         Label loop;
         __ bind(&loop);
         __ prefetch(Operand(src, 0x20), 1);
         __ movdqu(xmm0, Operand(src, 0x00));
         __ movdqu(xmm1, Operand(src, 0x10));
         __ add(Operand(src), Immediate(0x20));

         __ movdqa(Operand(dst, 0x00), xmm0);
         __ movdqa(Operand(dst, 0x10), xmm1);
         __ add(Operand(dst), Immediate(0x20));

         __ dec(loop_count);
         __ j(not_zero, &loop);
       }

       // At most 31 bytes to copy.
       Label move_less_16;
       __ test(Operand(count), Immediate(0x10));
       __ j(zero, &move_less_16);
       __ movdqu(xmm0, Operand(src, 0));
       __ add(Operand(src), Immediate(0x10));
       __ movdqa(Operand(dst, 0), xmm0);
       __ add(Operand(dst), Immediate(0x10));
       __ bind(&move_less_16);

       // At most 15 bytes to copy. Copy 16 bytes at end of string.
       __ and_(count, 0x0F);
       __ movdqu(xmm0, Operand(src, count, times_1, -0x10));
       __ movdqu(Operand(dst, count, times_1, -0x10), xmm0);

       __ mov(eax, Operand(esp, stack_offset + kDestinationOffset));
       __ pop(esi);
       __ pop(edi);
       __ ret(0);
     }

   } else {
     // SSE2 not supported. Unlikely to happen in practice.
     __ push(edi);
     __ push(esi);
     stack_offset += 2 * kPointerSize;
     __ cld();
     Register dst = edi;
     Register src = esi;
     Register count = ecx;
     __ mov(dst, Operand(esp, stack_offset + kDestinationOffset));
     __ mov(src, Operand(esp, stack_offset + kSourceOffset));
     __ mov(count, Operand(esp, stack_offset + kSizeOffset));

     // Copy the first word.
     __ mov(eax, Operand(src, 0));
     __ mov(Operand(dst, 0), eax);

     // Increment src,dstso that dst is aligned.
     __ mov(edx, dst);
     __ and_(edx, 0x03);
     __ neg(edx);
     __ add(Operand(edx), Immediate(4));  // edx = 4 - (dst & 3)
     __ add(dst, Operand(edx));
     __ add(src, Operand(edx));
     __ sub(Operand(count), edx);
     // edi is now aligned, ecx holds number of remaning bytes to copy.

     __ mov(edx, count);
     count = edx;
     __ shr(ecx, 2);  // Make word count instead of byte count.
     __ rep_movs();

     // At most 3 bytes left to copy. Copy 4 bytes at end of string.
     __ and_(count, 3);
     __ mov(eax, Operand(src, count, times_1, -4));
     __ mov(Operand(dst, count, times_1, -4), eax);

     __ mov(eax, Operand(esp, stack_offset + kDestinationOffset));
     __ pop(esi);
     __ pop(edi);
     __ ret(0);
   }

   CodeDesc desc;
   masm.GetCode(&desc);
   ASSERT(desc.reloc_size == 0);

   CPU::FlushICache(buffer, actual_size);
   OS::ProtectCode(buffer, actual_size);
   return FUNCTION_CAST<OS::MemCopyFunction>(buffer);
 }

 #undef __

 } }  // namespace v8::internal

 #endif  // V8_TARGET_ARCH_IA32
	// Copyright 2011 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_IA32)

	#include "codegen.h"

	namespace v8 {
	namespace internal {


	// -------------------------------------------------------------------------
	// Platform-specific RuntimeCallHelper functions.

	void StubRuntimeCallHelper::BeforeCall(MacroAssembler* masm) const {
	masm->EnterInternalFrame();
	}


	void StubRuntimeCallHelper::AfterCall(MacroAssembler* masm) const {
	masm->LeaveInternalFrame();
	}


	#define __ masm.

	static void MemCopyWrapper(void* dest, const void* src, size_t size) {
	memcpy(dest, src, size);
	}


	OS::MemCopyFunction CreateMemCopyFunction() {
	size_t actual_size;
	// Allocate buffer in executable space.
	byte* buffer = static_cast<byte>(OS::Allocate(1 KB,
	&actual_size,
	true));
	if (buffer == NULL) return &MemCopyWrapper;
	MacroAssembler masm(NULL, buffer, static_cast<int>(actual_size));

	// Generated code is put into a fixed, unmovable, buffer, and not into
	// the V8 heap. We can't, and don't, refer to any relocatable addresses
	// (e.g. the JavaScript nan-object).

	// 32-bit C declaration function calls pass arguments on stack.

	// Stack layout:
	// esp[12]: Third argument, size.
	// esp[8]: Second argument, source pointer.
	// esp[4]: First argument, destination pointer.
	// esp[0]: return address

	const int kDestinationOffset = 1 * kPointerSize;
	const int kSourceOffset = 2 * kPointerSize;
	const int kSizeOffset = 3 * kPointerSize;

	int stack_offset = 0; // Update if we change the stack height.

	if (FLAG_debug_code) {
	__ cmp(Operand(esp, kSizeOffset + stack_offset),
	Immediate(OS::kMinComplexMemCopy));
	Label ok;
	__ j(greater_equal, &ok);
	__ int3();
	__ bind(&ok);
	}
	if (CpuFeatures::IsSupported(SSE2)) {
	CpuFeatures::Scope enable(SSE2);
	__ push(edi);
	__ push(esi);
	stack_offset += 2 * kPointerSize;
	Register dst = edi;
	Register src = esi;
	Register count = ecx;
	__ mov(dst, Operand(esp, stack_offset + kDestinationOffset));
	__ mov(src, Operand(esp, stack_offset + kSourceOffset));
	__ mov(count, Operand(esp, stack_offset + kSizeOffset));


	__ movdqu(xmm0, Operand(src, 0));
	__ movdqu(Operand(dst, 0), xmm0);
	__ mov(edx, dst);
	__ and_(edx, 0xF);
	__ neg(edx);
	__ add(Operand(edx), Immediate(16));
	__ add(dst, Operand(edx));
	__ add(src, Operand(edx));
	__ sub(Operand(count), edx);

	// edi is now aligned. Check if esi is also aligned.
	Label unaligned_source;
	__ test(Operand(src), Immediate(0x0F));
	__ j(not_zero, &unaligned_source);
	{
	// Copy loop for aligned source and destination.
	__ mov(edx, count);
	Register loop_count = ecx;
	Register count = edx;
	__ shr(loop_count, 5);
	{
	// Main copy loop.
	Label loop;
	__ bind(&loop);
	__ prefetch(Operand(src, 0x20), 1);
	__ movdqa(xmm0, Operand(src, 0x00));
	__ movdqa(xmm1, Operand(src, 0x10));
	__ add(Operand(src), Immediate(0x20));

	__ movdqa(Operand(dst, 0x00), xmm0);
	__ movdqa(Operand(dst, 0x10), xmm1);
	__ add(Operand(dst), Immediate(0x20));

	__ dec(loop_count);
	__ j(not_zero, &loop);
	}

	// At most 31 bytes to copy.
	Label move_less_16;
	__ test(Operand(count), Immediate(0x10));
	__ j(zero, &move_less_16);
	__ movdqa(xmm0, Operand(src, 0));
	__ add(Operand(src), Immediate(0x10));
	__ movdqa(Operand(dst, 0), xmm0);
	__ add(Operand(dst), Immediate(0x10));
	__ bind(&move_less_16);

	// At most 15 bytes to copy. Copy 16 bytes at end of string.
	__ and_(count, 0xF);
	__ movdqu(xmm0, Operand(src, count, times_1, -0x10));
	__ movdqu(Operand(dst, count, times_1, -0x10), xmm0);

	__ mov(eax, Operand(esp, stack_offset + kDestinationOffset));
	__ pop(esi);
	__ pop(edi);
	__ ret(0);
	}
	__ Align(16);
	{
	// Copy loop for unaligned source and aligned destination.
	// If source is not aligned, we can't read it as efficiently.
	__ bind(&unaligned_source);
	__ mov(edx, ecx);
	Register loop_count = ecx;
	Register count = edx;
	__ shr(loop_count, 5);
	{
	// Main copy loop
	Label loop;
	__ bind(&loop);
	__ prefetch(Operand(src, 0x20), 1);
	__ movdqu(xmm0, Operand(src, 0x00));
	__ movdqu(xmm1, Operand(src, 0x10));
	__ add(Operand(src), Immediate(0x20));

	__ movdqa(Operand(dst, 0x00), xmm0);
	__ movdqa(Operand(dst, 0x10), xmm1);
	__ add(Operand(dst), Immediate(0x20));

	__ dec(loop_count);
	__ j(not_zero, &loop);
	}

	// At most 31 bytes to copy.
	Label move_less_16;
	__ test(Operand(count), Immediate(0x10));
	__ j(zero, &move_less_16);
	__ movdqu(xmm0, Operand(src, 0));
	__ add(Operand(src), Immediate(0x10));
	__ movdqa(Operand(dst, 0), xmm0);
	__ add(Operand(dst), Immediate(0x10));
	__ bind(&move_less_16);

	// At most 15 bytes to copy. Copy 16 bytes at end of string.
	__ and_(count, 0x0F);
	__ movdqu(xmm0, Operand(src, count, times_1, -0x10));
	__ movdqu(Operand(dst, count, times_1, -0x10), xmm0);

	__ mov(eax, Operand(esp, stack_offset + kDestinationOffset));
	__ pop(esi);
	__ pop(edi);
	__ ret(0);
	}

	} else {
	// SSE2 not supported. Unlikely to happen in practice.
	__ push(edi);
	__ push(esi);
	stack_offset += 2 * kPointerSize;
	__ cld();
	Register dst = edi;
	Register src = esi;
	Register count = ecx;
	__ mov(dst, Operand(esp, stack_offset + kDestinationOffset));
	__ mov(src, Operand(esp, stack_offset + kSourceOffset));
	__ mov(count, Operand(esp, stack_offset + kSizeOffset));

	// Copy the first word.
	__ mov(eax, Operand(src, 0));
	__ mov(Operand(dst, 0), eax);

	// Increment src,dstso that dst is aligned.
	__ mov(edx, dst);
	__ and_(edx, 0x03);
	__ neg(edx);
	__ add(Operand(edx), Immediate(4)); // edx = 4 - (dst & 3)
	__ add(dst, Operand(edx));
	__ add(src, Operand(edx));
	__ sub(Operand(count), edx);
	// edi is now aligned, ecx holds number of remaning bytes to copy.

	__ mov(edx, count);
	count = edx;
	__ shr(ecx, 2); // Make word count instead of byte count.
	__ rep_movs();

	// At most 3 bytes left to copy. Copy 4 bytes at end of string.
	__ and_(count, 3);
	__ mov(eax, Operand(src, count, times_1, -4));
	__ mov(Operand(dst, count, times_1, -4), eax);

	__ mov(eax, Operand(esp, stack_offset + kDestinationOffset));
	__ pop(esi);
	__ pop(edi);
	__ ret(0);
	}

	CodeDesc desc;
	masm.GetCode(&desc);
	ASSERT(desc.reloc_size == 0);

	CPU::FlushICache(buffer, actual_size);
	OS::ProtectCode(buffer, actual_size);
	return FUNCTION_CAST<OS::MemCopyFunction>(buffer);
	}

	#undef __

	} } // namespace v8::internal

	#endif // V8_TARGET_ARCH_IA32