//===- AsmWriterEmitter.cpp - Generate an assembly writer -----------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This tablegen backend is emits an assembly printer for the current target.
// Note that this is currently fairly skeletal, but will grow over time.
//
//===----------------------------------------------------------------------===//
#include "AsmWriterEmitter.h"
#include "AsmWriterInst.h"
#include "CodeGenTarget.h"
#include "StringToOffsetTable.h"
#include "SequenceToOffsetTable.h"
#include "llvm/ADT/Twine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/MathExtras.h"
#include "llvm/TableGen/Error.h"
#include "llvm/TableGen/Record.h"
#include <algorithm>
using namespace llvm;
static void PrintCases(std::vector<std::pair<std::string,
AsmWriterOperand> > &OpsToPrint, raw_ostream &O) {
O << " case " << OpsToPrint.back().first << ": ";
AsmWriterOperand TheOp = OpsToPrint.back().second;
OpsToPrint.pop_back();
// Check to see if any other operands are identical in this list, and if so,
// emit a case label for them.
for (unsigned i = OpsToPrint.size(); i != 0; --i)
if (OpsToPrint[i-1].second == TheOp) {
O << "\n case " << OpsToPrint[i-1].first << ": ";
OpsToPrint.erase(OpsToPrint.begin()+i-1);
}
// Finally, emit the code.
O << TheOp.getCode();
O << "break;\n";
}
/// EmitInstructions - Emit the last instruction in the vector and any other
/// instructions that are suitably similar to it.
static void EmitInstructions(std::vector<AsmWriterInst> &Insts,
raw_ostream &O) {
AsmWriterInst FirstInst = Insts.back();
Insts.pop_back();
std::vector<AsmWriterInst> SimilarInsts;
unsigned DifferingOperand = ~0;
for (unsigned i = Insts.size(); i != 0; --i) {
unsigned DiffOp = Insts[i-1].MatchesAllButOneOp(FirstInst);
if (DiffOp != ~1U) {
if (DifferingOperand == ~0U) // First match!
DifferingOperand = DiffOp;
// If this differs in the same operand as the rest of the instructions in
// this class, move it to the SimilarInsts list.
if (DifferingOperand == DiffOp || DiffOp == ~0U) {
SimilarInsts.push_back(Insts[i-1]);
Insts.erase(Insts.begin()+i-1);
}
}
}
O << " case " << FirstInst.CGI->Namespace << "::"
<< FirstInst.CGI->TheDef->getName() << ":\n";
for (unsigned i = 0, e = SimilarInsts.size(); i != e; ++i)
O << " case " << SimilarInsts[i].CGI->Namespace << "::"
<< SimilarInsts[i].CGI->TheDef->getName() << ":\n";
for (unsigned i = 0, e = FirstInst.Operands.size(); i != e; ++i) {
if (i != DifferingOperand) {
// If the operand is the same for all instructions, just print it.
O << " " << FirstInst.Operands[i].getCode();
} else {
// If this is the operand that varies between all of the instructions,
// emit a switch for just this operand now.
O << " switch (MI->getOpcode()) {\n";
std::vector<std::pair<std::string, AsmWriterOperand> > OpsToPrint;
OpsToPrint.push_back(std::make_pair(FirstInst.CGI->Namespace + "::" +
FirstInst.CGI->TheDef->getName(),
FirstInst.Operands[i]));
for (unsigned si = 0, e = SimilarInsts.size(); si != e; ++si) {
AsmWriterInst &AWI = SimilarInsts[si];
OpsToPrint.push_back(std::make_pair(AWI.CGI->Namespace+"::"+
AWI.CGI->TheDef->getName(),
AWI.Operands[i]));
}
std::reverse(OpsToPrint.begin(), OpsToPrint.end());
while (!OpsToPrint.empty())
PrintCases(OpsToPrint, O);
O << " }";
}
O << "\n";
}
O << " break;\n";
}
void AsmWriterEmitter::
FindUniqueOperandCommands(std::vector<std::string> &UniqueOperandCommands,
std::vector<unsigned> &InstIdxs,
std::vector<unsigned> &InstOpsUsed) const {
InstIdxs.assign(NumberedInstructions.size(), ~0U);
// This vector parallels UniqueOperandCommands, keeping track of which
// instructions each case are used for. It is a comma separated string of
// enums.
std::vector<std::string> InstrsForCase;
InstrsForCase.resize(UniqueOperandCommands.size());
InstOpsUsed.assign(UniqueOperandCommands.size(), 0);
for (unsigned i = 0, e = NumberedInstructions.size(); i != e; ++i) {
const AsmWriterInst *Inst = getAsmWriterInstByID(i);
if (Inst == 0) continue; // PHI, INLINEASM, PROLOG_LABEL, etc.
std::string Command;
if (Inst->Operands.empty())
continue; // Instruction already done.
Command = " " + Inst->Operands[0].getCode() + "\n";
// Check to see if we already have 'Command' in UniqueOperandCommands.
// If not, add it.
bool FoundIt = false;
for (unsigned idx = 0, e = UniqueOperandCommands.size(); idx != e; ++idx)
if (UniqueOperandCommands[idx] == Command) {
InstIdxs[i] = idx;
InstrsForCase[idx] += ", ";
InstrsForCase[idx] += Inst->CGI->TheDef->getName();
FoundIt = true;
break;
}
if (!FoundIt) {
InstIdxs[i] = UniqueOperandCommands.size();
UniqueOperandCommands.push_back(Command);
InstrsForCase.push_back(Inst->CGI->TheDef->getName());
// This command matches one operand so far.
InstOpsUsed.push_back(1);
}
}
// For each entry of UniqueOperandCommands, there is a set of instructions
// that uses it. If the next command of all instructions in the set are
// identical, fold it into the command.
for (unsigned CommandIdx = 0, e = UniqueOperandCommands.size();
CommandIdx != e; ++CommandIdx) {
for (unsigned Op = 1; ; ++Op) {
// Scan for the first instruction in the set.
std::vector<unsigned>::iterator NIT =
std::find(InstIdxs.begin(), InstIdxs.end(), CommandIdx);
if (NIT == InstIdxs.end()) break; // No commonality.
// If this instruction has no more operands, we isn't anything to merge
// into this command.
const AsmWriterInst *FirstInst =
getAsmWriterInstByID(NIT-InstIdxs.begin());
if (!FirstInst || FirstInst->Operands.size() == Op)
break;
// Otherwise, scan to see if all of the other instructions in this command
// set share the operand.
bool AllSame = true;
// Keep track of the maximum, number of operands or any
// instruction we see in the group.
size_t MaxSize = FirstInst->Operands.size();
for (NIT = std::find(NIT+1, InstIdxs.end(), CommandIdx);
NIT != InstIdxs.end();
NIT = std::find(NIT+1, InstIdxs.end(), CommandIdx)) {
// Okay, found another instruction in this command set. If the operand
// matches, we're ok, otherwise bail out.
const AsmWriterInst *OtherInst =
getAsmWriterInstByID(NIT-InstIdxs.begin());
if (OtherInst &&
OtherInst->Operands.size() > FirstInst->Operands.size())
MaxSize = std::max(MaxSize, OtherInst->Operands.size());
if (!OtherInst || OtherInst->Operands.size() == Op ||
OtherInst->Operands[Op] != FirstInst->Operands[Op]) {
AllSame = false;
break;
}
}
if (!AllSame) break;
// Okay, everything in this command set has the same next operand. Add it
// to UniqueOperandCommands and remember that it was consumed.
std::string Command = " " + FirstInst->Operands[Op].getCode() + "\n";
UniqueOperandCommands[CommandIdx] += Command;
InstOpsUsed[CommandIdx]++;
}
}
// Prepend some of the instructions each case is used for onto the case val.
for (unsigned i = 0, e = InstrsForCase.size(); i != e; ++i) {
std::string Instrs = InstrsForCase[i];
if (Instrs.size() > 70) {
Instrs.erase(Instrs.begin()+70, Instrs.end());
Instrs += "...";
}
if (!Instrs.empty())
UniqueOperandCommands[i] = " // " + Instrs + "\n" +
UniqueOperandCommands[i];
}
}
static void UnescapeString(std::string &Str) {
for (unsigned i = 0; i != Str.size(); ++i) {
if (Str[i] == '\\' && i != Str.size()-1) {
switch (Str[i+1]) {
default: continue; // Don't execute the code after the switch.
case 'a': Str[i] = '\a'; break;
case 'b': Str[i] = '\b'; break;
case 'e': Str[i] = 27; break;
case 'f': Str[i] = '\f'; break;
case 'n': Str[i] = '\n'; break;
case 'r': Str[i] = '\r'; break;
case 't': Str[i] = '\t'; break;
case 'v': Str[i] = '\v'; break;
case '"': Str[i] = '\"'; break;
case '\'': Str[i] = '\''; break;
case '\\': Str[i] = '\\'; break;
}
// Nuke the second character.
Str.erase(Str.begin()+i+1);
}
}
}
/// EmitPrintInstruction - Generate the code for the "printInstruction" method
/// implementation.
void AsmWriterEmitter::EmitPrintInstruction(raw_ostream &O) {
CodeGenTarget Target(Records);
Record *AsmWriter = Target.getAsmWriter();
std::string ClassName = AsmWriter->getValueAsString("AsmWriterClassName");
bool isMC = AsmWriter->getValueAsBit("isMCAsmWriter");
const char *MachineInstrClassName = isMC ? "MCInst" : "MachineInstr";
O <<
"/// printInstruction - This method is automatically generated by tablegen\n"
"/// from the instruction set description.\n"
"void " << Target.getName() << ClassName
<< "::printInstruction(const " << MachineInstrClassName
<< " *MI, raw_ostream &O) {\n";
std::vector<AsmWriterInst> Instructions;
for (CodeGenTarget::inst_iterator I = Target.inst_begin(),
E = Target.inst_end(); I != E; ++I)
if (!(*I)->AsmString.empty() &&
(*I)->TheDef->getName() != "PHI")
Instructions.push_back(
AsmWriterInst(**I,
AsmWriter->getValueAsInt("Variant"),
AsmWriter->getValueAsInt("FirstOperandColumn"),
AsmWriter->getValueAsInt("OperandSpacing")));
// Get the instruction numbering.
NumberedInstructions = Target.getInstructionsByEnumValue();
// Compute the CodeGenInstruction -> AsmWriterInst mapping. Note that not
// all machine instructions are necessarily being printed, so there may be
// target instructions not in this map.
for (unsigned i = 0, e = Instructions.size(); i != e; ++i)
CGIAWIMap.insert(std::make_pair(Instructions[i].CGI, &Instructions[i]));
// Build an aggregate string, and build a table of offsets into it.
SequenceToOffsetTable<std::string> StringTable;
/// OpcodeInfo - This encodes the index of the string to use for the first
/// chunk of the output as well as indices used for operand printing.
std::vector<unsigned> OpcodeInfo;
// Add all strings to the string table upfront so it can generate an optimized
// representation.
for (unsigned i = 0, e = NumberedInstructions.size(); i != e; ++i) {
AsmWriterInst *AWI = CGIAWIMap[NumberedInstructions[i]];
if (AWI != 0 &&
AWI->Operands[0].OperandType ==
AsmWriterOperand::isLiteralTextOperand &&
!AWI->Operands[0].Str.empty()) {
std::string Str = AWI->Operands[0].Str;
UnescapeString(Str);
StringTable.add(Str);
}
}
StringTable.layout();
unsigned MaxStringIdx = 0;
for (unsigned i = 0, e = NumberedInstructions.size(); i != e; ++i) {
AsmWriterInst *AWI = CGIAWIMap[NumberedInstructions[i]];
unsigned Idx;
if (AWI == 0) {
// Something not handled by the asmwriter printer.
Idx = ~0U;
} else if (AWI->Operands[0].OperandType !=
AsmWriterOperand::isLiteralTextOperand ||
AWI->Operands[0].Str.empty()) {
// Something handled by the asmwriter printer, but with no leading string.
Idx = StringTable.get("");
} else {
std::string Str = AWI->Operands[0].Str;
UnescapeString(Str);
Idx = StringTable.get(Str);
MaxStringIdx = std::max(MaxStringIdx, Idx);
// Nuke the string from the operand list. It is now handled!
AWI->Operands.erase(AWI->Operands.begin());
}
// Bias offset by one since we want 0 as a sentinel.
OpcodeInfo.push_back(Idx+1);
}
// Figure out how many bits we used for the string index.
unsigned AsmStrBits = Log2_32_Ceil(MaxStringIdx+2);
// To reduce code size, we compactify common instructions into a few bits
// in the opcode-indexed table.
unsigned BitsLeft = 32-AsmStrBits;
std::vector<std::vector<std::string> > TableDrivenOperandPrinters;
while (1) {
std::vector<std::string> UniqueOperandCommands;
std::vector<unsigned> InstIdxs;
std::vector<unsigned> NumInstOpsHandled;
FindUniqueOperandCommands(UniqueOperandCommands, InstIdxs,
NumInstOpsHandled);
// If we ran out of operands to print, we're done.
if (UniqueOperandCommands.empty()) break;
// Compute the number of bits we need to represent these cases, this is
// ceil(log2(numentries)).
unsigned NumBits = Log2_32_Ceil(UniqueOperandCommands.size());
// If we don't have enough bits for this operand, don't include it.
if (NumBits > BitsLeft) {
DEBUG(errs() << "Not enough bits to densely encode " << NumBits
<< " more bits\n");
break;
}
// Otherwise, we can include this in the initial lookup table. Add it in.
BitsLeft -= NumBits;
for (unsigned i = 0, e = InstIdxs.size(); i != e; ++i)
if (InstIdxs[i] != ~0U)
OpcodeInfo[i] |= InstIdxs[i] << (BitsLeft+AsmStrBits);
// Remove the info about this operand.
for (unsigned i = 0, e = NumberedInstructions.size(); i != e; ++i) {
if (AsmWriterInst *Inst = getAsmWriterInstByID(i))
if (!Inst->Operands.empty()) {
unsigned NumOps = NumInstOpsHandled[InstIdxs[i]];
assert(NumOps <= Inst->Operands.size() &&
"Can't remove this many ops!");
Inst->Operands.erase(Inst->Operands.begin(),
Inst->Operands.begin()+NumOps);
}
}
// Remember the handlers for this set of operands.
TableDrivenOperandPrinters.push_back(UniqueOperandCommands);
}
O<<" static const unsigned OpInfo[] = {\n";
for (unsigned i = 0, e = NumberedInstructions.size(); i != e; ++i) {
O << " " << OpcodeInfo[i] << "U,\t// "
<< NumberedInstructions[i]->TheDef->getName() << "\n";
}
// Add a dummy entry so the array init doesn't end with a comma.
O << " 0U\n";
O << " };\n\n";
// Emit the string itself.
O << " const char AsmStrs[] = {\n";
StringTable.emit(O, printChar);
O << " };\n\n";
O << " O << \"\\t\";\n\n";
O << " // Emit the opcode for the instruction.\n"
<< " unsigned Bits = OpInfo[MI->getOpcode()];\n"
<< " assert(Bits != 0 && \"Cannot print this instruction.\");\n"
<< " O << AsmStrs+(Bits & " << (1 << AsmStrBits)-1 << ")-1;\n\n";
// Output the table driven operand information.
BitsLeft = 32-AsmStrBits;
for (unsigned i = 0, e = TableDrivenOperandPrinters.size(); i != e; ++i) {
std::vector<std::string> &Commands = TableDrivenOperandPrinters[i];
// Compute the number of bits we need to represent these cases, this is
// ceil(log2(numentries)).
unsigned NumBits = Log2_32_Ceil(Commands.size());
assert(NumBits <= BitsLeft && "consistency error");
// Emit code to extract this field from Bits.
BitsLeft -= NumBits;
O << "\n // Fragment " << i << " encoded into " << NumBits
<< " bits for " << Commands.size() << " unique commands.\n";
if (Commands.size() == 2) {
// Emit two possibilitys with if/else.
O << " if ((Bits >> " << (BitsLeft+AsmStrBits) << ") & "
<< ((1 << NumBits)-1) << ") {\n"
<< Commands[1]
<< " } else {\n"
<< Commands[0]
<< " }\n\n";
} else if (Commands.size() == 1) {
// Emit a single possibility.
O << Commands[0] << "\n\n";
} else {
O << " switch ((Bits >> " << (BitsLeft+AsmStrBits) << ") & "
<< ((1 << NumBits)-1) << ") {\n"
<< " default: // unreachable.\n";
// Print out all the cases.
for (unsigned i = 0, e = Commands.size(); i != e; ++i) {
O << " case " << i << ":\n";
O << Commands[i];
O << " break;\n";
}
O << " }\n\n";
}
}
// Okay, delete instructions with no operand info left.
for (unsigned i = 0, e = Instructions.size(); i != e; ++i) {
// Entire instruction has been emitted?
AsmWriterInst &Inst = Instructions[i];
if (Inst.Operands.empty()) {
Instructions.erase(Instructions.begin()+i);
--i; --e;
}
}
// Because this is a vector, we want to emit from the end. Reverse all of the
// elements in the vector.
std::reverse(Instructions.begin(), Instructions.end());
// Now that we've emitted all of the operand info that fit into 32 bits, emit
// information for those instructions that are left. This is a less dense
// encoding, but we expect the main 32-bit table to handle the majority of
// instructions.
if (!Instructions.empty()) {
// Find the opcode # of inline asm.
O << " switch (MI->getOpcode()) {\n";
while (!Instructions.empty())
EmitInstructions(Instructions, O);
O << " }\n";
O << " return;\n";
}
O << "}\n";
}
static void
emitRegisterNameString(raw_ostream &O, StringRef AltName,
const std::vector<CodeGenRegister*> &Registers) {
SequenceToOffsetTable<std::string> StringTable;
SmallVector<std::string, 4> AsmNames(Registers.size());
for (unsigned i = 0, e = Registers.size(); i != e; ++i) {
const CodeGenRegister &Reg = *Registers[i];
std::string &AsmName = AsmNames[i];
// "NoRegAltName" is special. We don't need to do a lookup for that,
// as it's just a reference to the default register name.
if (AltName == "" || AltName == "NoRegAltName") {
AsmName = Reg.TheDef->getValueAsString("AsmName");
if (AsmName.empty())
AsmName = Reg.getName();
} else {
// Make sure the register has an alternate name for this index.
std::vector<Record*> AltNameList =
Reg.TheDef->getValueAsListOfDefs("RegAltNameIndices");
unsigned Idx = 0, e;
for (e = AltNameList.size();
Idx < e && (AltNameList[Idx]->getName() != AltName);
++Idx)
;
// If the register has an alternate name for this index, use it.
// Otherwise, leave it empty as an error flag.
if (Idx < e) {
std::vector<std::string> AltNames =
Reg.TheDef->getValueAsListOfStrings("AltNames");
if (AltNames.size() <= Idx)
throw TGError(Reg.TheDef->getLoc(),
(Twine("Register definition missing alt name for '") +
AltName + "'.").str());
AsmName = AltNames[Idx];
}
}
StringTable.add(AsmName);
}
StringTable.layout();
O << " static const char AsmStrs" << AltName << "[] = {\n";
StringTable.emit(O, printChar);
O << " };\n\n";
O << " static const unsigned RegAsmOffset" << AltName << "[] = {";
for (unsigned i = 0, e = Registers.size(); i != e; ++i) {
if ((i % 14) == 0)
O << "\n ";
O << StringTable.get(AsmNames[i]) << ", ";
}
O << "\n };\n"
<< "\n";
}
void AsmWriterEmitter::EmitGetRegisterName(raw_ostream &O) {
CodeGenTarget Target(Records);
Record *AsmWriter = Target.getAsmWriter();
std::string ClassName = AsmWriter->getValueAsString("AsmWriterClassName");
const std::vector<CodeGenRegister*> &Registers =
Target.getRegBank().getRegisters();
std::vector<Record*> AltNameIndices = Target.getRegAltNameIndices();
bool hasAltNames = AltNameIndices.size() > 1;
O <<
"\n\n/// getRegisterName - This method is automatically generated by tblgen\n"
"/// from the register set description. This returns the assembler name\n"
"/// for the specified register.\n"
"const char *" << Target.getName() << ClassName << "::";
if (hasAltNames)
O << "\ngetRegisterName(unsigned RegNo, unsigned AltIdx) {\n";
else
O << "getRegisterName(unsigned RegNo) {\n";
O << " assert(RegNo && RegNo < " << (Registers.size()+1)
<< " && \"Invalid register number!\");\n"
<< "\n";
if (hasAltNames) {
for (unsigned i = 0, e = AltNameIndices.size(); i < e; ++i)
emitRegisterNameString(O, AltNameIndices[i]->getName(), Registers);
} else
emitRegisterNameString(O, "", Registers);
if (hasAltNames) {
O << " const unsigned *RegAsmOffset;\n"
<< " const char *AsmStrs;\n"
<< " switch(AltIdx) {\n"
<< " default: llvm_unreachable(\"Invalid register alt name index!\");\n";
for (unsigned i = 0, e = AltNameIndices.size(); i < e; ++i) {
StringRef Namespace = AltNameIndices[1]->getValueAsString("Namespace");
StringRef AltName(AltNameIndices[i]->getName());
O << " case " << Namespace << "::" << AltName
<< ":\n"
<< " AsmStrs = AsmStrs" << AltName << ";\n"
<< " RegAsmOffset = RegAsmOffset" << AltName << ";\n"
<< " break;\n";
}
O << "}\n";
}
O << " assert (*(AsmStrs+RegAsmOffset[RegNo-1]) &&\n"
<< " \"Invalid alt name index for register!\");\n"
<< " return AsmStrs+RegAsmOffset[RegNo-1];\n"
<< "}\n";
}
namespace {
// IAPrinter - Holds information about an InstAlias. Two InstAliases match if
// they both have the same conditionals. In which case, we cannot print out the
// alias for that pattern.
class IAPrinter {
std::vector<std::string> Conds;
std::map<StringRef, unsigned> OpMap;
std::string Result;
std::string AsmString;
SmallVector<Record*, 4> ReqFeatures;
public:
IAPrinter(std::string R, std::string AS)
: Result(R), AsmString(AS) {}
void addCond(const std::string &C) { Conds.push_back(C); }
void addOperand(StringRef Op, unsigned Idx) { OpMap[Op] = Idx; }
unsigned getOpIndex(StringRef Op) { return OpMap[Op]; }
bool isOpMapped(StringRef Op) { return OpMap.find(Op) != OpMap.end(); }
void print(raw_ostream &O) {
if (Conds.empty() && ReqFeatures.empty()) {
O.indent(6) << "return true;\n";
return;
}
O << "if (";
for (std::vector<std::string>::iterator
I = Conds.begin(), E = Conds.end(); I != E; ++I) {
if (I != Conds.begin()) {
O << " &&\n";
O.indent(8);
}
O << *I;
}
O << ") {\n";
O.indent(6) << "// " << Result << "\n";
O.indent(6) << "AsmString = \"" << AsmString << "\";\n";
for (std::map<StringRef, unsigned>::iterator
I = OpMap.begin(), E = OpMap.end(); I != E; ++I)
O.indent(6) << "OpMap.push_back(std::make_pair(\"" << I->first << "\", "
<< I->second << "));\n";
O.indent(6) << "break;\n";
O.indent(4) << '}';
}
bool operator==(const IAPrinter &RHS) {
if (Conds.size() != RHS.Conds.size())
return false;
unsigned Idx = 0;
for (std::vector<std::string>::iterator
I = Conds.begin(), E = Conds.end(); I != E; ++I)
if (*I != RHS.Conds[Idx++])
return false;
return true;
}
bool operator()(const IAPrinter &RHS) {
if (Conds.size() < RHS.Conds.size())
return true;
unsigned Idx = 0;
for (std::vector<std::string>::iterator
I = Conds.begin(), E = Conds.end(); I != E; ++I)
if (*I != RHS.Conds[Idx++])
return *I < RHS.Conds[Idx++];
return false;
}
};
} // end anonymous namespace
static void EmitGetMapOperandNumber(raw_ostream &O) {
O << "static unsigned getMapOperandNumber("
<< "const SmallVectorImpl<std::pair<StringRef, unsigned> > &OpMap,\n";
O << " StringRef Name) {\n";
O << " for (SmallVectorImpl<std::pair<StringRef, unsigned> >::"
<< "const_iterator\n";
O << " I = OpMap.begin(), E = OpMap.end(); I != E; ++I)\n";
O << " if (I->first == Name)\n";
O << " return I->second;\n";
O << " llvm_unreachable(\"Operand not in map!\");\n";
O << "}\n\n";
}
static unsigned CountNumOperands(StringRef AsmString) {
unsigned NumOps = 0;
std::pair<StringRef, StringRef> ASM = AsmString.split(' ');
while (!ASM.second.empty()) {
++NumOps;
ASM = ASM.second.split(' ');
}
return NumOps;
}
static unsigned CountResultNumOperands(StringRef AsmString) {
unsigned NumOps = 0;
std::pair<StringRef, StringRef> ASM = AsmString.split('\t');
if (!ASM.second.empty()) {
size_t I = ASM.second.find('{');
StringRef Str = ASM.second;
if (I != StringRef::npos)
Str = ASM.second.substr(I, ASM.second.find('|', I));
ASM = Str.split(' ');
do {
++NumOps;
ASM = ASM.second.split(' ');
} while (!ASM.second.empty());
}
return NumOps;
}
void AsmWriterEmitter::EmitPrintAliasInstruction(raw_ostream &O) {
CodeGenTarget Target(Records);
Record *AsmWriter = Target.getAsmWriter();
if (!AsmWriter->getValueAsBit("isMCAsmWriter"))
return;
O << "\n#ifdef PRINT_ALIAS_INSTR\n";
O << "#undef PRINT_ALIAS_INSTR\n\n";
// Emit the method that prints the alias instruction.
std::string ClassName = AsmWriter->getValueAsString("AsmWriterClassName");
std::vector<Record*> AllInstAliases =
Records.getAllDerivedDefinitions("InstAlias");
// Create a map from the qualified name to a list of potential matches.
std::map<std::string, std::vector<CodeGenInstAlias*> > AliasMap;
for (std::vector<Record*>::iterator
I = AllInstAliases.begin(), E = AllInstAliases.end(); I != E; ++I) {
CodeGenInstAlias *Alias = new CodeGenInstAlias(*I, Target);
const Record *R = *I;
if (!R->getValueAsBit("EmitAlias"))
continue; // We were told not to emit the alias, but to emit the aliasee.
const DagInit *DI = R->getValueAsDag("ResultInst");
const DefInit *Op = dynamic_cast<const DefInit*>(DI->getOperator());
AliasMap[getQualifiedName(Op->getDef())].push_back(Alias);
}
// A map of which conditions need to be met for each instruction operand
// before it can be matched to the mnemonic.
std::map<std::string, std::vector<IAPrinter*> > IAPrinterMap;
for (std::map<std::string, std::vector<CodeGenInstAlias*> >::iterator
I = AliasMap.begin(), E = AliasMap.end(); I != E; ++I) {
std::vector<CodeGenInstAlias*> &Aliases = I->second;
for (std::vector<CodeGenInstAlias*>::iterator
II = Aliases.begin(), IE = Aliases.end(); II != IE; ++II) {
const CodeGenInstAlias *CGA = *II;
unsigned LastOpNo = CGA->ResultInstOperandIndex.size();
unsigned NumResultOps =
CountResultNumOperands(CGA->ResultInst->AsmString);
// Don't emit the alias if it has more operands than what it's aliasing.
if (NumResultOps < CountNumOperands(CGA->AsmString))
continue;
IAPrinter *IAP = new IAPrinter(CGA->Result->getAsString(),
CGA->AsmString);
std::string Cond;
Cond = std::string("MI->getNumOperands() == ") + llvm::utostr(LastOpNo);
IAP->addCond(Cond);
std::map<StringRef, unsigned> OpMap;
bool CantHandle = false;
for (unsigned i = 0, e = LastOpNo; i != e; ++i) {
const CodeGenInstAlias::ResultOperand &RO = CGA->ResultOperands[i];
switch (RO.Kind) {
case CodeGenInstAlias::ResultOperand::K_Record: {
const Record *Rec = RO.getRecord();
StringRef ROName = RO.getName();
if (Rec->isSubClassOf("RegisterOperand"))
Rec = Rec->getValueAsDef("RegClass");
if (Rec->isSubClassOf("RegisterClass")) {
Cond = std::string("MI->getOperand(")+llvm::utostr(i)+").isReg()";
IAP->addCond(Cond);
if (!IAP->isOpMapped(ROName)) {
IAP->addOperand(ROName, i);
Cond = std::string("MRI.getRegClass(") + Target.getName() + "::" +
CGA->ResultOperands[i].getRecord()->getName() + "RegClassID)"
".contains(MI->getOperand(" + llvm::utostr(i) + ").getReg())";
IAP->addCond(Cond);
} else {
Cond = std::string("MI->getOperand(") +
llvm::utostr(i) + ").getReg() == MI->getOperand(" +
llvm::utostr(IAP->getOpIndex(ROName)) + ").getReg()";
IAP->addCond(Cond);
}
} else {
assert(Rec->isSubClassOf("Operand") && "Unexpected operand!");
// FIXME: We may need to handle these situations.
delete IAP;
IAP = 0;
CantHandle = true;
break;
}
break;
}
case CodeGenInstAlias::ResultOperand::K_Imm:
Cond = std::string("MI->getOperand(") +
llvm::utostr(i) + ").getImm() == " +
llvm::utostr(CGA->ResultOperands[i].getImm());
IAP->addCond(Cond);
break;
case CodeGenInstAlias::ResultOperand::K_Reg:
// If this is zero_reg, something's playing tricks we're not
// equipped to handle.
if (!CGA->ResultOperands[i].getRegister()) {
CantHandle = true;
break;
}
Cond = std::string("MI->getOperand(") +
llvm::utostr(i) + ").getReg() == " + Target.getName() +
"::" + CGA->ResultOperands[i].getRegister()->getName();
IAP->addCond(Cond);
break;
}
if (!IAP) break;
}
if (CantHandle) continue;
IAPrinterMap[I->first].push_back(IAP);
}
}
std::string Header;
raw_string_ostream HeaderO(Header);
HeaderO << "bool " << Target.getName() << ClassName
<< "::printAliasInstr(const MCInst"
<< " *MI, raw_ostream &OS) {\n";
std::string Cases;
raw_string_ostream CasesO(Cases);
for (std::map<std::string, std::vector<IAPrinter*> >::iterator
I = IAPrinterMap.begin(), E = IAPrinterMap.end(); I != E; ++I) {
std::vector<IAPrinter*> &IAPs = I->second;
std::vector<IAPrinter*> UniqueIAPs;
for (std::vector<IAPrinter*>::iterator
II = IAPs.begin(), IE = IAPs.end(); II != IE; ++II) {
IAPrinter *LHS = *II;
bool IsDup = false;
for (std::vector<IAPrinter*>::iterator
III = IAPs.begin(), IIE = IAPs.end(); III != IIE; ++III) {
IAPrinter *RHS = *III;
if (LHS != RHS && *LHS == *RHS) {
IsDup = true;
break;
}
}
if (!IsDup) UniqueIAPs.push_back(LHS);
}
if (UniqueIAPs.empty()) continue;
CasesO.indent(2) << "case " << I->first << ":\n";
for (std::vector<IAPrinter*>::iterator
II = UniqueIAPs.begin(), IE = UniqueIAPs.end(); II != IE; ++II) {
IAPrinter *IAP = *II;
CasesO.indent(4);
IAP->print(CasesO);
CasesO << '\n';
}
CasesO.indent(4) << "return false;\n";
}
if (CasesO.str().empty()) {
O << HeaderO.str();
O << " return false;\n";
O << "}\n\n";
O << "#endif // PRINT_ALIAS_INSTR\n";
return;
}
EmitGetMapOperandNumber(O);
O << HeaderO.str();
O.indent(2) << "StringRef AsmString;\n";
O.indent(2) << "SmallVector<std::pair<StringRef, unsigned>, 4> OpMap;\n";
O.indent(2) << "switch (MI->getOpcode()) {\n";
O.indent(2) << "default: return false;\n";
O << CasesO.str();
O.indent(2) << "}\n\n";
// Code that prints the alias, replacing the operands with the ones from the
// MCInst.
O << " std::pair<StringRef, StringRef> ASM = AsmString.split(' ');\n";
O << " OS << '\\t' << ASM.first;\n";
O << " if (!ASM.second.empty()) {\n";
O << " OS << '\\t';\n";
O << " for (StringRef::iterator\n";
O << " I = ASM.second.begin(), E = ASM.second.end(); I != E; ) {\n";
O << " if (*I == '$') {\n";
O << " StringRef::iterator Start = ++I;\n";
O << " while (I != E &&\n";
O << " ((*I >= 'a' && *I <= 'z') ||\n";
O << " (*I >= 'A' && *I <= 'Z') ||\n";
O << " (*I >= '0' && *I <= '9') ||\n";
O << " *I == '_'))\n";
O << " ++I;\n";
O << " StringRef Name(Start, I - Start);\n";
O << " printOperand(MI, getMapOperandNumber(OpMap, Name), OS);\n";
O << " } else {\n";
O << " OS << *I++;\n";
O << " }\n";
O << " }\n";
O << " }\n\n";
O << " return true;\n";
O << "}\n\n";
O << "#endif // PRINT_ALIAS_INSTR\n";
}
void AsmWriterEmitter::run(raw_ostream &O) {
EmitSourceFileHeader("Assembly Writer Source Fragment", O);
EmitPrintInstruction(O);
EmitGetRegisterName(O);
EmitPrintAliasInstruction(O);
}