| //===- AsmWriterInst.h - Classes encapsulating a printable inst -----------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // These classes implement a parser for assembly strings. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "AsmWriterInst.h" |
| #include "CodeGenTarget.h" |
| #include "llvm/ADT/StringExtras.h" |
| #include "llvm/TableGen/Error.h" |
| #include "llvm/TableGen/Record.h" |
| |
| using namespace llvm; |
| |
| static bool isIdentChar(char C) { |
| return (C >= 'a' && C <= 'z') || |
| (C >= 'A' && C <= 'Z') || |
| (C >= '0' && C <= '9') || |
| C == '_'; |
| } |
| |
| std::string AsmWriterOperand::getCode() const { |
| if (OperandType == isLiteralTextOperand) { |
| if (Str.size() == 1) |
| return "O << '" + Str + "'; "; |
| return "O << \"" + Str + "\"; "; |
| } |
| |
| if (OperandType == isLiteralStatementOperand) |
| return Str; |
| |
| std::string Result = Str + "(MI"; |
| if (MIOpNo != ~0U) |
| Result += ", " + utostr(MIOpNo); |
| Result += ", O"; |
| if (!MiModifier.empty()) |
| Result += ", \"" + MiModifier + '"'; |
| return Result + "); "; |
| } |
| |
| /// ParseAsmString - Parse the specified Instruction's AsmString into this |
| /// AsmWriterInst. |
| /// |
| AsmWriterInst::AsmWriterInst(const CodeGenInstruction &CGI, |
| unsigned Variant, |
| int FirstOperandColumn, |
| int OperandSpacing) { |
| this->CGI = &CGI; |
| |
| // This is the number of tabs we've seen if we're doing columnar layout. |
| unsigned CurColumn = 0; |
| |
| |
| // NOTE: Any extensions to this code need to be mirrored in the |
| // AsmPrinter::printInlineAsm code that executes as compile time (assuming |
| // that inline asm strings should also get the new feature)! |
| std::string AsmString = CGI.FlattenAsmStringVariants(CGI.AsmString, Variant); |
| std::string::size_type LastEmitted = 0; |
| while (LastEmitted != AsmString.size()) { |
| std::string::size_type DollarPos = |
| AsmString.find_first_of("$\\", LastEmitted); |
| if (DollarPos == std::string::npos) DollarPos = AsmString.size(); |
| |
| // Emit a constant string fragment. |
| if (DollarPos != LastEmitted) { |
| for (; LastEmitted != DollarPos; ++LastEmitted) |
| switch (AsmString[LastEmitted]) { |
| case '\n': |
| AddLiteralString("\\n"); |
| break; |
| case '\t': |
| // If the asm writer is not using a columnar layout, \t is not |
| // magic. |
| if (FirstOperandColumn == -1 || OperandSpacing == -1) { |
| AddLiteralString("\\t"); |
| } else { |
| // We recognize a tab as an operand delimeter. |
| unsigned DestColumn = FirstOperandColumn + |
| CurColumn++ * OperandSpacing; |
| Operands.push_back( |
| AsmWriterOperand( |
| "O.PadToColumn(" + |
| utostr(DestColumn) + ");\n", |
| AsmWriterOperand::isLiteralStatementOperand)); |
| } |
| break; |
| case '"': |
| AddLiteralString("\\\""); |
| break; |
| case '\\': |
| AddLiteralString("\\\\"); |
| break; |
| default: |
| AddLiteralString(std::string(1, AsmString[LastEmitted])); |
| break; |
| } |
| } else if (AsmString[DollarPos] == '\\') { |
| if (DollarPos+1 != AsmString.size()) { |
| if (AsmString[DollarPos+1] == 'n') { |
| AddLiteralString("\\n"); |
| } else if (AsmString[DollarPos+1] == 't') { |
| // If the asm writer is not using a columnar layout, \t is not |
| // magic. |
| if (FirstOperandColumn == -1 || OperandSpacing == -1) { |
| AddLiteralString("\\t"); |
| break; |
| } |
| |
| // We recognize a tab as an operand delimeter. |
| unsigned DestColumn = FirstOperandColumn + |
| CurColumn++ * OperandSpacing; |
| Operands.push_back( |
| AsmWriterOperand("O.PadToColumn(" + utostr(DestColumn) + ");\n", |
| AsmWriterOperand::isLiteralStatementOperand)); |
| break; |
| } else if (std::string("${|}\\").find(AsmString[DollarPos+1]) |
| != std::string::npos) { |
| AddLiteralString(std::string(1, AsmString[DollarPos+1])); |
| } else { |
| PrintFatalError("Non-supported escaped character found in instruction '" + |
| CGI.TheDef->getName() + "'!"); |
| } |
| LastEmitted = DollarPos+2; |
| continue; |
| } |
| } else if (DollarPos+1 != AsmString.size() && |
| AsmString[DollarPos+1] == '$') { |
| AddLiteralString("$"); // "$$" -> $ |
| LastEmitted = DollarPos+2; |
| } else { |
| // Get the name of the variable. |
| std::string::size_type VarEnd = DollarPos+1; |
| |
| // handle ${foo}bar as $foo by detecting whether the character following |
| // the dollar sign is a curly brace. If so, advance VarEnd and DollarPos |
| // so the variable name does not contain the leading curly brace. |
| bool hasCurlyBraces = false; |
| if (VarEnd < AsmString.size() && '{' == AsmString[VarEnd]) { |
| hasCurlyBraces = true; |
| ++DollarPos; |
| ++VarEnd; |
| } |
| |
| while (VarEnd < AsmString.size() && isIdentChar(AsmString[VarEnd])) |
| ++VarEnd; |
| std::string VarName(AsmString.begin()+DollarPos+1, |
| AsmString.begin()+VarEnd); |
| |
| // Modifier - Support ${foo:modifier} syntax, where "modifier" is passed |
| // into printOperand. Also support ${:feature}, which is passed into |
| // PrintSpecial. |
| std::string Modifier; |
| |
| // In order to avoid starting the next string at the terminating curly |
| // brace, advance the end position past it if we found an opening curly |
| // brace. |
| if (hasCurlyBraces) { |
| if (VarEnd >= AsmString.size()) |
| PrintFatalError("Reached end of string before terminating curly brace in '" |
| + CGI.TheDef->getName() + "'"); |
| |
| // Look for a modifier string. |
| if (AsmString[VarEnd] == ':') { |
| ++VarEnd; |
| if (VarEnd >= AsmString.size()) |
| PrintFatalError("Reached end of string before terminating curly brace in '" |
| + CGI.TheDef->getName() + "'"); |
| |
| unsigned ModifierStart = VarEnd; |
| while (VarEnd < AsmString.size() && isIdentChar(AsmString[VarEnd])) |
| ++VarEnd; |
| Modifier = std::string(AsmString.begin()+ModifierStart, |
| AsmString.begin()+VarEnd); |
| if (Modifier.empty()) |
| PrintFatalError("Bad operand modifier name in '"+ CGI.TheDef->getName() + "'"); |
| } |
| |
| if (AsmString[VarEnd] != '}') |
| PrintFatalError("Variable name beginning with '{' did not end with '}' in '" |
| + CGI.TheDef->getName() + "'"); |
| ++VarEnd; |
| } |
| if (VarName.empty() && Modifier.empty()) |
| PrintFatalError("Stray '$' in '" + CGI.TheDef->getName() + |
| "' asm string, maybe you want $$?"); |
| |
| if (VarName.empty()) { |
| // Just a modifier, pass this into PrintSpecial. |
| Operands.push_back(AsmWriterOperand("PrintSpecial", |
| ~0U, |
| ~0U, |
| Modifier)); |
| } else { |
| // Otherwise, normal operand. |
| unsigned OpNo = CGI.Operands.getOperandNamed(VarName); |
| CGIOperandList::OperandInfo OpInfo = CGI.Operands[OpNo]; |
| |
| unsigned MIOp = OpInfo.MIOperandNo; |
| Operands.push_back(AsmWriterOperand(OpInfo.PrinterMethodName, |
| OpNo, MIOp, Modifier)); |
| } |
| LastEmitted = VarEnd; |
| } |
| } |
| |
| Operands.push_back(AsmWriterOperand("return;", |
| AsmWriterOperand::isLiteralStatementOperand)); |
| } |
| |
| /// MatchesAllButOneOp - If this instruction is exactly identical to the |
| /// specified instruction except for one differing operand, return the differing |
| /// operand number. If more than one operand mismatches, return ~1, otherwise |
| /// if the instructions are identical return ~0. |
| unsigned AsmWriterInst::MatchesAllButOneOp(const AsmWriterInst &Other)const{ |
| if (Operands.size() != Other.Operands.size()) return ~1; |
| |
| unsigned MismatchOperand = ~0U; |
| for (unsigned i = 0, e = Operands.size(); i != e; ++i) { |
| if (Operands[i] != Other.Operands[i]) { |
| if (MismatchOperand != ~0U) // Already have one mismatch? |
| return ~1U; |
| else |
| MismatchOperand = i; |
| } |
| } |
| return MismatchOperand; |
| } |
