1 //===-- X86IntelAsmPrinter.cpp - Convert X86 LLVM code to Intel assembly --===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by the LLVM research group and is distributed under
6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file contains a printer that converts from our internal representation
11 // of machine-dependent LLVM code to Intel format assembly language.
12 // This printer is the output mechanism used by `llc'.
14 //===----------------------------------------------------------------------===//
16 #define DEBUG_TYPE "asm-printer"
17 #include "X86IntelAsmPrinter.h"
18 #include "X86TargetAsmInfo.h"
20 #include "llvm/CallingConv.h"
21 #include "llvm/Constants.h"
22 #include "llvm/Module.h"
23 #include "llvm/Assembly/Writer.h"
24 #include "llvm/Support/Mangler.h"
25 #include "llvm/Target/TargetAsmInfo.h"
26 #include "llvm/Target/TargetOptions.h"
27 #include "llvm/ADT/Statistic.h"
30 STATISTIC(EmittedInsts, "Number of machine instrs printed");
32 std::string X86IntelAsmPrinter::getSectionForFunction(const Function &F) const {
33 // Intel asm always emits functions to _text.
37 /// runOnMachineFunction - This uses the printMachineInstruction()
38 /// method to print assembly for each instruction.
40 bool X86IntelAsmPrinter::runOnMachineFunction(MachineFunction &MF) {
41 SetupMachineFunction(MF);
44 // Print out constants referenced by the function
45 EmitConstantPool(MF.getConstantPool());
47 // Print out labels for the function.
48 const Function *F = MF.getFunction();
49 unsigned CC = F->getCallingConv();
51 // Populate function information map. Actually, We don't want to populate
52 // non-stdcall or non-fastcall functions' information right now.
53 if (CC == CallingConv::X86_StdCall || CC == CallingConv::X86_FastCall)
54 FunctionInfoMap[F] = *MF.getInfo<X86FunctionInfo>();
56 X86SharedAsmPrinter::decorateName(CurrentFnName, F);
58 SwitchToTextSection(getSectionForFunction(*F).c_str(), F);
60 switch (F->getLinkage()) {
61 default: assert(0 && "Unsupported linkage type!");
62 case Function::InternalLinkage:
65 case Function::DLLExportLinkage:
66 DLLExportedFns.insert(CurrentFnName);
68 case Function::ExternalLinkage:
69 O << "\tpublic " << CurrentFnName << "\n";
74 O << CurrentFnName << "\tproc near\n";
76 // Print out code for the function.
77 for (MachineFunction::const_iterator I = MF.begin(), E = MF.end();
79 // Print a label for the basic block if there are any predecessors.
80 if (I->pred_begin() != I->pred_end()) {
81 printBasicBlockLabel(I, true);
84 for (MachineBasicBlock::const_iterator II = I->begin(), E = I->end();
86 // Print the assembly for the instruction.
88 printMachineInstruction(II);
92 // Print out jump tables referenced by the function.
93 EmitJumpTableInfo(MF.getJumpTableInfo(), MF);
95 O << CurrentFnName << "\tendp\n";
97 // We didn't modify anything.
101 void X86IntelAsmPrinter::printSSECC(const MachineInstr *MI, unsigned Op) {
102 unsigned char value = MI->getOperand(Op).getImmedValue();
103 assert(value <= 7 && "Invalid ssecc argument!");
105 case 0: O << "eq"; break;
106 case 1: O << "lt"; break;
107 case 2: O << "le"; break;
108 case 3: O << "unord"; break;
109 case 4: O << "neq"; break;
110 case 5: O << "nlt"; break;
111 case 6: O << "nle"; break;
112 case 7: O << "ord"; break;
116 void X86IntelAsmPrinter::printOp(const MachineOperand &MO,
117 const char *Modifier) {
118 const MRegisterInfo &RI = *TM.getRegisterInfo();
119 switch (MO.getType()) {
120 case MachineOperand::MO_Register: {
121 if (MRegisterInfo::isPhysicalRegister(MO.getReg())) {
122 unsigned Reg = MO.getReg();
123 if (Modifier && strncmp(Modifier, "subreg", strlen("subreg")) == 0) {
124 MVT::ValueType VT = (strcmp(Modifier,"subreg64") == 0) ?
125 MVT::i64 : ((strcmp(Modifier, "subreg32") == 0) ? MVT::i32 :
126 ((strcmp(Modifier,"subreg16") == 0) ? MVT::i16 :MVT::i8));
127 Reg = getX86SubSuperRegister(Reg, VT);
129 O << RI.get(Reg).Name;
131 O << "reg" << MO.getReg();
134 case MachineOperand::MO_Immediate:
135 O << MO.getImmedValue();
137 case MachineOperand::MO_MachineBasicBlock:
138 printBasicBlockLabel(MO.getMachineBasicBlock());
140 case MachineOperand::MO_JumpTableIndex: {
141 bool isMemOp = Modifier && !strcmp(Modifier, "mem");
142 if (!isMemOp) O << "OFFSET ";
143 O << TAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber()
144 << "_" << MO.getJumpTableIndex();
147 case MachineOperand::MO_ConstantPoolIndex: {
148 bool isMemOp = Modifier && !strcmp(Modifier, "mem");
149 if (!isMemOp) O << "OFFSET ";
150 O << "[" << TAI->getPrivateGlobalPrefix() << "CPI"
151 << getFunctionNumber() << "_" << MO.getConstantPoolIndex();
152 int Offset = MO.getOffset();
154 O << " + " << Offset;
160 case MachineOperand::MO_GlobalAddress: {
161 bool isCallOp = Modifier && !strcmp(Modifier, "call");
162 bool isMemOp = Modifier && !strcmp(Modifier, "mem");
163 GlobalValue *GV = MO.getGlobal();
164 std::string Name = Mang->getValueName(GV);
166 X86SharedAsmPrinter::decorateName(Name, GV);
168 if (!isMemOp && !isCallOp) O << "OFFSET ";
169 if (GV->hasDLLImportLinkage()) {
170 // FIXME: This should be fixed with full support of stdcall & fastcall
175 int Offset = MO.getOffset();
177 O << " + " << Offset;
182 case MachineOperand::MO_ExternalSymbol: {
183 bool isCallOp = Modifier && !strcmp(Modifier, "call");
184 if (!isCallOp) O << "OFFSET ";
185 O << TAI->getGlobalPrefix() << MO.getSymbolName();
189 O << "<unknown operand type>"; return;
193 void X86IntelAsmPrinter::printMemReference(const MachineInstr *MI, unsigned Op,
194 const char *Modifier) {
195 assert(isMem(MI, Op) && "Invalid memory reference!");
197 const MachineOperand &BaseReg = MI->getOperand(Op);
198 int ScaleVal = MI->getOperand(Op+1).getImmedValue();
199 const MachineOperand &IndexReg = MI->getOperand(Op+2);
200 const MachineOperand &DispSpec = MI->getOperand(Op+3);
203 bool NeedPlus = false;
204 if (BaseReg.getReg()) {
205 printOp(BaseReg, Modifier);
209 if (IndexReg.getReg()) {
210 if (NeedPlus) O << " + ";
212 O << ScaleVal << "*";
213 printOp(IndexReg, Modifier);
217 if (DispSpec.isGlobalAddress() || DispSpec.isConstantPoolIndex() ||
218 DispSpec.isJumpTableIndex()) {
221 printOp(DispSpec, "mem");
223 int DispVal = DispSpec.getImmedValue();
224 if (DispVal || (!BaseReg.getReg() && !IndexReg.getReg())) {
238 void X86IntelAsmPrinter::printPICLabel(const MachineInstr *MI, unsigned Op) {
239 O << "\"L" << getFunctionNumber() << "$pb\"\n";
240 O << "\"L" << getFunctionNumber() << "$pb\":";
243 bool X86IntelAsmPrinter::printAsmMRegister(const MachineOperand &MO,
245 const MRegisterInfo &RI = *TM.getRegisterInfo();
246 unsigned Reg = MO.getReg();
248 default: return true; // Unknown mode.
249 case 'b': // Print QImode register
250 Reg = getX86SubSuperRegister(Reg, MVT::i8);
252 case 'h': // Print QImode high register
253 Reg = getX86SubSuperRegister(Reg, MVT::i8, true);
255 case 'w': // Print HImode register
256 Reg = getX86SubSuperRegister(Reg, MVT::i16);
258 case 'k': // Print SImode register
259 Reg = getX86SubSuperRegister(Reg, MVT::i32);
263 O << '%' << RI.get(Reg).Name;
267 /// PrintAsmOperand - Print out an operand for an inline asm expression.
269 bool X86IntelAsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
271 const char *ExtraCode) {
272 // Does this asm operand have a single letter operand modifier?
273 if (ExtraCode && ExtraCode[0]) {
274 if (ExtraCode[1] != 0) return true; // Unknown modifier.
276 switch (ExtraCode[0]) {
277 default: return true; // Unknown modifier.
278 case 'b': // Print QImode register
279 case 'h': // Print QImode high register
280 case 'w': // Print HImode register
281 case 'k': // Print SImode register
282 return printAsmMRegister(MI->getOperand(OpNo), ExtraCode[0]);
286 printOperand(MI, OpNo);
290 bool X86IntelAsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI,
293 const char *ExtraCode) {
294 if (ExtraCode && ExtraCode[0])
295 return true; // Unknown modifier.
296 printMemReference(MI, OpNo);
300 /// printMachineInstruction -- Print out a single X86 LLVM instruction
301 /// MI in Intel syntax to the current output stream.
303 void X86IntelAsmPrinter::printMachineInstruction(const MachineInstr *MI) {
306 // See if a truncate instruction can be turned into a nop.
307 switch (MI->getOpcode()) {
309 case X86::TRUNC_64to32:
310 case X86::TRUNC_64to16:
311 case X86::TRUNC_32to16:
312 case X86::TRUNC_32to8:
313 case X86::TRUNC_16to8:
314 case X86::TRUNC_32_to8:
315 case X86::TRUNC_16_to8: {
316 const MachineOperand &MO0 = MI->getOperand(0);
317 const MachineOperand &MO1 = MI->getOperand(1);
318 unsigned Reg0 = MO0.getReg();
319 unsigned Reg1 = MO1.getReg();
320 unsigned Opc = MI->getOpcode();
321 if (Opc == X86::TRUNC_64to32)
322 Reg1 = getX86SubSuperRegister(Reg1, MVT::i32);
323 else if (Opc == X86::TRUNC_32to16 || Opc == X86::TRUNC_64to16)
324 Reg1 = getX86SubSuperRegister(Reg1, MVT::i16);
326 Reg1 = getX86SubSuperRegister(Reg1, MVT::i8);
327 O << TAI->getCommentString() << " TRUNCATE ";
332 case X86::PsMOVZX64rr32:
333 O << TAI->getCommentString() << " ZERO-EXTEND " << "\n\t";
337 // Call the autogenerated instruction printer routines.
338 printInstruction(MI);
341 bool X86IntelAsmPrinter::doInitialization(Module &M) {
342 X86SharedAsmPrinter::doInitialization(M);
344 Mang->markCharUnacceptable('.');
346 O << "\t.686\n\t.model flat\n\n";
348 // Emit declarations for external functions.
349 for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I)
350 if (I->isDeclaration()) {
351 std::string Name = Mang->getValueName(I);
352 X86SharedAsmPrinter::decorateName(Name, I);
355 if (I->hasDLLImportLinkage()) {
358 O << Name << ":near\n";
361 // Emit declarations for external globals. Note that VC++ always declares
362 // external globals to have type byte, and if that's good enough for VC++...
363 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
365 if (I->isDeclaration()) {
366 std::string Name = Mang->getValueName(I);
369 if (I->hasDLLImportLinkage()) {
372 O << Name << ":byte\n";
379 bool X86IntelAsmPrinter::doFinalization(Module &M) {
380 const TargetData *TD = TM.getTargetData();
382 // Print out module-level global variables here.
383 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
385 if (I->isDeclaration()) continue; // External global require no code
387 // Check to see if this is a special global used by LLVM, if so, emit it.
388 if (EmitSpecialLLVMGlobal(I))
391 std::string name = Mang->getValueName(I);
392 Constant *C = I->getInitializer();
393 unsigned Align = TD->getPreferredAlignmentLog(I);
394 bool bCustomSegment = false;
396 switch (I->getLinkage()) {
397 case GlobalValue::LinkOnceLinkage:
398 case GlobalValue::WeakLinkage:
399 SwitchToDataSection("");
400 O << name << "?\tsegment common 'COMMON'\n";
401 bCustomSegment = true;
402 // FIXME: the default alignment is 16 bytes, but 1, 2, 4, and 256
403 // are also available.
405 case GlobalValue::AppendingLinkage:
406 SwitchToDataSection("");
407 O << name << "?\tsegment public 'DATA'\n";
408 bCustomSegment = true;
409 // FIXME: the default alignment is 16 bytes, but 1, 2, 4, and 256
410 // are also available.
412 case GlobalValue::DLLExportLinkage:
413 DLLExportedGVs.insert(name);
415 case GlobalValue::ExternalLinkage:
416 O << "\tpublic " << name << "\n";
418 case GlobalValue::InternalLinkage:
419 SwitchToDataSection(TAI->getDataSection(), I);
422 assert(0 && "Unknown linkage type!");
426 EmitAlignment(Align, I);
428 O << name << ":\t\t\t\t" << TAI->getCommentString()
429 << " " << I->getName() << '\n';
431 EmitGlobalConstant(C);
434 O << name << "?\tends\n";
437 // Output linker support code for dllexported globals
438 if ((DLLExportedGVs.begin() != DLLExportedGVs.end()) ||
439 (DLLExportedFns.begin() != DLLExportedFns.end())) {
440 SwitchToDataSection("");
441 O << "; WARNING: The following code is valid only with MASM v8.x and (possible) higher\n"
442 << "; This version of MASM is usually shipped with Microsoft Visual Studio 2005\n"
443 << "; or (possible) further versions. Unfortunately, there is no way to support\n"
444 << "; dllexported symbols in the earlier versions of MASM in fully automatic way\n\n";
445 O << "_drectve\t segment info alias('.drectve')\n";
448 for (std::set<std::string>::iterator i = DLLExportedGVs.begin(),
449 e = DLLExportedGVs.end();
451 O << "\t db ' /EXPORT:" << *i << ",data'\n";
454 for (std::set<std::string>::iterator i = DLLExportedFns.begin(),
455 e = DLLExportedFns.end();
457 O << "\t db ' /EXPORT:" << *i << "'\n";
460 if ((DLLExportedGVs.begin() != DLLExportedGVs.end()) ||
461 (DLLExportedFns.begin() != DLLExportedFns.end())) {
462 O << "_drectve\t ends\n";
465 // Bypass X86SharedAsmPrinter::doFinalization().
466 AsmPrinter::doFinalization(M);
467 SwitchToDataSection("");
469 return false; // success
472 void X86IntelAsmPrinter::EmitString(const ConstantArray *CVA) const {
473 unsigned NumElts = CVA->getNumOperands();
475 // ML does not have escape sequences except '' for '. It also has a maximum
476 // string length of 255.
478 bool inString = false;
479 for (unsigned i = 0; i < NumElts; i++) {
480 int n = cast<ConstantInt>(CVA->getOperand(i))->getZExtValue() & 255;
484 if (n >= 32 && n <= 127) {
511 len += 1 + (n > 9) + (n > 99);
532 // Include the auto-generated portion of the assembly writer.
533 #include "X86GenAsmWriter1.inc"