1 //===-- X86MCInstLower.cpp - Convert X86 MachineInstr to an MCInst --------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file contains code to lower X86 MachineInstrs to their corresponding
13 //===----------------------------------------------------------------------===//
15 #include "X86MCInstLower.h"
16 #include "X86AsmPrinter.h"
17 #include "X86COFFMachineModuleInfo.h"
18 #include "X86MCAsmInfo.h"
19 #include "X86MCTargetExpr.h"
20 #include "llvm/Analysis/DebugInfo.h"
21 #include "llvm/CodeGen/MachineModuleInfoImpls.h"
22 #include "llvm/MC/MCContext.h"
23 #include "llvm/MC/MCExpr.h"
24 #include "llvm/MC/MCInst.h"
25 #include "llvm/MC/MCStreamer.h"
26 #include "llvm/Target/Mangler.h"
27 #include "llvm/Support/FormattedStream.h"
28 #include "llvm/ADT/SmallString.h"
29 #include "llvm/Type.h"
33 const X86Subtarget &X86MCInstLower::getSubtarget() const {
34 return AsmPrinter.getSubtarget();
37 MachineModuleInfoMachO &X86MCInstLower::getMachOMMI() const {
38 assert(getSubtarget().isTargetDarwin() &&"Can only get MachO info on darwin");
39 return AsmPrinter.MMI->getObjFileInfo<MachineModuleInfoMachO>();
43 MCSymbol *X86MCInstLower::GetPICBaseSymbol() const {
44 const TargetLowering *TLI = AsmPrinter.TM.getTargetLowering();
45 return static_cast<const X86TargetLowering*>(TLI)->
46 getPICBaseSymbol(AsmPrinter.MF, Ctx);
49 /// LowerGlobalAddressOperand - Lower an MO_GlobalAddress operand to an
51 MCSymbol *X86MCInstLower::
52 GetGlobalAddressSymbol(const MachineOperand &MO) const {
53 const GlobalValue *GV = MO.getGlobal();
55 bool isImplicitlyPrivate = false;
56 if (MO.getTargetFlags() == X86II::MO_DARWIN_STUB ||
57 MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY ||
58 MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY_PIC_BASE ||
59 MO.getTargetFlags() == X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE)
60 isImplicitlyPrivate = true;
62 SmallString<128> Name;
63 Mang->getNameWithPrefix(Name, GV, isImplicitlyPrivate);
65 if (getSubtarget().isTargetCygMing()) {
66 X86COFFMachineModuleInfo &COFFMMI =
67 AsmPrinter.MMI->getObjFileInfo<X86COFFMachineModuleInfo>();
68 COFFMMI.DecorateCygMingName(Name, GV, *AsmPrinter.TM.getTargetData());
71 switch (MO.getTargetFlags()) {
72 default: llvm_unreachable("Unknown target flag on GV operand");
73 case X86II::MO_NO_FLAG: // These don't modify the symbol name.
74 case X86II::MO_PIC_BASE_OFFSET:
76 case X86II::MO_GOTTPOFF:
77 case X86II::MO_INDNTPOFF:
79 case X86II::MO_NTPOFF:
80 case X86II::MO_GOTPCREL:
82 case X86II::MO_GOTOFF:
85 case X86II::MO_DLLIMPORT: {
86 // Handle dllimport linkage.
87 const char *Prefix = "__imp_";
88 Name.insert(Name.begin(), Prefix, Prefix+strlen(Prefix));
91 case X86II::MO_DARWIN_NONLAZY:
92 case X86II::MO_DARWIN_NONLAZY_PIC_BASE: {
93 Name += "$non_lazy_ptr";
94 MCSymbol *Sym = Ctx.GetOrCreateSymbol(Name.str());
96 MCSymbol *&StubSym = getMachOMMI().getGVStubEntry(Sym);
98 StubSym = AsmPrinter.GetGlobalValueSymbol(GV);
101 case X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE: {
102 Name += "$non_lazy_ptr";
103 MCSymbol *Sym = Ctx.GetOrCreateSymbol(Name.str());
104 MCSymbol *&StubSym = getMachOMMI().getHiddenGVStubEntry(Sym);
106 StubSym = AsmPrinter.GetGlobalValueSymbol(GV);
109 case X86II::MO_DARWIN_STUB: {
111 MCSymbol *Sym = Ctx.GetOrCreateSymbol(Name.str());
112 MCSymbol *&StubSym = getMachOMMI().getFnStubEntry(Sym);
114 StubSym = AsmPrinter.GetGlobalValueSymbol(GV);
119 return Ctx.GetOrCreateSymbol(Name.str());
122 MCSymbol *X86MCInstLower::
123 GetExternalSymbolSymbol(const MachineOperand &MO) const {
124 SmallString<128> Name;
125 Name += AsmPrinter.MAI->getGlobalPrefix();
126 Name += MO.getSymbolName();
128 switch (MO.getTargetFlags()) {
129 default: llvm_unreachable("Unknown target flag on GV operand");
130 case X86II::MO_NO_FLAG: // These don't modify the symbol name.
131 case X86II::MO_GOT_ABSOLUTE_ADDRESS: // Doesn't modify symbol name.
132 case X86II::MO_PIC_BASE_OFFSET:
133 case X86II::MO_TLSGD:
134 case X86II::MO_GOTTPOFF:
135 case X86II::MO_INDNTPOFF:
136 case X86II::MO_TPOFF:
137 case X86II::MO_NTPOFF:
138 case X86II::MO_GOTPCREL:
140 case X86II::MO_GOTOFF:
143 case X86II::MO_DLLIMPORT: {
144 // Handle dllimport linkage.
145 const char *Prefix = "__imp_";
146 Name.insert(Name.begin(), Prefix, Prefix+strlen(Prefix));
149 case X86II::MO_DARWIN_STUB: {
151 MCSymbol *Sym = Ctx.GetOrCreateSymbol(Name.str());
152 MCSymbol *&StubSym = getMachOMMI().getFnStubEntry(Sym);
155 Name.erase(Name.end()-5, Name.end());
156 StubSym = Ctx.GetOrCreateSymbol(Name.str());
162 return Ctx.GetOrCreateSymbol(Name.str());
165 MCOperand X86MCInstLower::LowerSymbolOperand(const MachineOperand &MO,
166 MCSymbol *Sym) const {
167 // FIXME: We would like an efficient form for this, so we don't have to do a
168 // lot of extra uniquing.
169 const MCExpr *Expr = 0;
170 X86MCTargetExpr::VariantKind RefKind = X86MCTargetExpr::Invalid;
172 switch (MO.getTargetFlags()) {
173 default: llvm_unreachable("Unknown target flag on GV operand");
174 case X86II::MO_NO_FLAG: // No flag.
175 // These affect the name of the symbol, not any suffix.
176 case X86II::MO_DARWIN_NONLAZY:
177 case X86II::MO_DLLIMPORT:
178 case X86II::MO_DARWIN_STUB:
181 case X86II::MO_TLSGD: RefKind = X86MCTargetExpr::TLSGD; break;
182 case X86II::MO_GOTTPOFF: RefKind = X86MCTargetExpr::GOTTPOFF; break;
183 case X86II::MO_INDNTPOFF: RefKind = X86MCTargetExpr::INDNTPOFF; break;
184 case X86II::MO_TPOFF: RefKind = X86MCTargetExpr::TPOFF; break;
185 case X86II::MO_NTPOFF: RefKind = X86MCTargetExpr::NTPOFF; break;
186 case X86II::MO_GOTPCREL: RefKind = X86MCTargetExpr::GOTPCREL; break;
187 case X86II::MO_GOT: RefKind = X86MCTargetExpr::GOT; break;
188 case X86II::MO_GOTOFF: RefKind = X86MCTargetExpr::GOTOFF; break;
189 case X86II::MO_PLT: RefKind = X86MCTargetExpr::PLT; break;
190 case X86II::MO_PIC_BASE_OFFSET:
191 case X86II::MO_DARWIN_NONLAZY_PIC_BASE:
192 case X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE:
193 Expr = MCSymbolRefExpr::Create(Sym, Ctx);
194 // Subtract the pic base.
195 Expr = MCBinaryExpr::CreateSub(Expr,
196 MCSymbolRefExpr::Create(GetPICBaseSymbol(), Ctx),
202 if (RefKind == X86MCTargetExpr::Invalid)
203 Expr = MCSymbolRefExpr::Create(Sym, Ctx);
205 Expr = X86MCTargetExpr::Create(Sym, RefKind, Ctx);
208 if (!MO.isJTI() && MO.getOffset())
209 Expr = MCBinaryExpr::CreateAdd(Expr,
210 MCConstantExpr::Create(MO.getOffset(), Ctx),
212 return MCOperand::CreateExpr(Expr);
217 static void lower_subreg32(MCInst *MI, unsigned OpNo) {
218 // Convert registers in the addr mode according to subreg32.
219 unsigned Reg = MI->getOperand(OpNo).getReg();
221 MI->getOperand(OpNo).setReg(getX86SubSuperRegister(Reg, MVT::i32));
224 static void lower_lea64_32mem(MCInst *MI, unsigned OpNo) {
225 // Convert registers in the addr mode according to subreg64.
226 for (unsigned i = 0; i != 4; ++i) {
227 if (!MI->getOperand(OpNo+i).isReg()) continue;
229 unsigned Reg = MI->getOperand(OpNo+i).getReg();
230 if (Reg == 0) continue;
232 MI->getOperand(OpNo+i).setReg(getX86SubSuperRegister(Reg, MVT::i64));
236 /// LowerSubReg32_Op0 - Things like MOVZX16rr8 -> MOVZX32rr8.
237 static void LowerSubReg32_Op0(MCInst &OutMI, unsigned NewOpc) {
238 OutMI.setOpcode(NewOpc);
239 lower_subreg32(&OutMI, 0);
241 /// LowerUnaryToTwoAddr - R = setb -> R = sbb R, R
242 static void LowerUnaryToTwoAddr(MCInst &OutMI, unsigned NewOpc) {
243 OutMI.setOpcode(NewOpc);
244 OutMI.addOperand(OutMI.getOperand(0));
245 OutMI.addOperand(OutMI.getOperand(0));
249 void X86MCInstLower::Lower(const MachineInstr *MI, MCInst &OutMI) const {
250 OutMI.setOpcode(MI->getOpcode());
252 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
253 const MachineOperand &MO = MI->getOperand(i);
256 switch (MO.getType()) {
259 llvm_unreachable("unknown operand type");
260 case MachineOperand::MO_Register:
261 // Ignore all implicit register operands.
262 if (MO.isImplicit()) continue;
263 MCOp = MCOperand::CreateReg(MO.getReg());
265 case MachineOperand::MO_Immediate:
266 MCOp = MCOperand::CreateImm(MO.getImm());
268 case MachineOperand::MO_MachineBasicBlock:
269 MCOp = MCOperand::CreateExpr(MCSymbolRefExpr::Create(
270 MO.getMBB()->getSymbol(Ctx), Ctx));
272 case MachineOperand::MO_GlobalAddress:
273 MCOp = LowerSymbolOperand(MO, GetGlobalAddressSymbol(MO));
275 case MachineOperand::MO_ExternalSymbol:
276 MCOp = LowerSymbolOperand(MO, GetExternalSymbolSymbol(MO));
278 case MachineOperand::MO_JumpTableIndex:
279 MCOp = LowerSymbolOperand(MO, AsmPrinter.GetJTISymbol(MO.getIndex()));
281 case MachineOperand::MO_ConstantPoolIndex:
282 MCOp = LowerSymbolOperand(MO, AsmPrinter.GetCPISymbol(MO.getIndex()));
284 case MachineOperand::MO_BlockAddress:
285 MCOp = LowerSymbolOperand(MO,
286 AsmPrinter.GetBlockAddressSymbol(MO.getBlockAddress()));
290 OutMI.addOperand(MCOp);
293 // Handle a few special cases to eliminate operand modifiers.
294 switch (OutMI.getOpcode()) {
295 case X86::LEA64_32r: // Handle 'subreg rewriting' for the lea64_32mem operand.
296 lower_lea64_32mem(&OutMI, 1);
298 case X86::MOVZX16rr8: LowerSubReg32_Op0(OutMI, X86::MOVZX32rr8); break;
299 case X86::MOVZX16rm8: LowerSubReg32_Op0(OutMI, X86::MOVZX32rm8); break;
300 case X86::MOVSX16rr8: LowerSubReg32_Op0(OutMI, X86::MOVSX32rr8); break;
301 case X86::MOVSX16rm8: LowerSubReg32_Op0(OutMI, X86::MOVSX32rm8); break;
302 case X86::MOVZX64rr32: LowerSubReg32_Op0(OutMI, X86::MOV32rr); break;
303 case X86::MOVZX64rm32: LowerSubReg32_Op0(OutMI, X86::MOV32rm); break;
304 case X86::MOV64ri64i32: LowerSubReg32_Op0(OutMI, X86::MOV32ri); break;
305 case X86::MOVZX64rr8: LowerSubReg32_Op0(OutMI, X86::MOVZX32rr8); break;
306 case X86::MOVZX64rm8: LowerSubReg32_Op0(OutMI, X86::MOVZX32rm8); break;
307 case X86::MOVZX64rr16: LowerSubReg32_Op0(OutMI, X86::MOVZX32rr16); break;
308 case X86::MOVZX64rm16: LowerSubReg32_Op0(OutMI, X86::MOVZX32rm16); break;
309 case X86::SETB_C8r: LowerUnaryToTwoAddr(OutMI, X86::SBB8rr); break;
310 case X86::SETB_C16r: LowerUnaryToTwoAddr(OutMI, X86::SBB16rr); break;
311 case X86::SETB_C32r: LowerUnaryToTwoAddr(OutMI, X86::SBB32rr); break;
312 case X86::SETB_C64r: LowerUnaryToTwoAddr(OutMI, X86::SBB64rr); break;
313 case X86::MOV8r0: LowerUnaryToTwoAddr(OutMI, X86::XOR8rr); break;
314 case X86::MOV32r0: LowerUnaryToTwoAddr(OutMI, X86::XOR32rr); break;
315 case X86::MMX_V_SET0: LowerUnaryToTwoAddr(OutMI, X86::MMX_PXORrr); break;
316 case X86::MMX_V_SETALLONES:
317 LowerUnaryToTwoAddr(OutMI, X86::MMX_PCMPEQDrr); break;
318 case X86::FsFLD0SS: LowerUnaryToTwoAddr(OutMI, X86::PXORrr); break;
319 case X86::FsFLD0SD: LowerUnaryToTwoAddr(OutMI, X86::PXORrr); break;
320 case X86::V_SET0: LowerUnaryToTwoAddr(OutMI, X86::XORPSrr); break;
321 case X86::V_SETALLONES: LowerUnaryToTwoAddr(OutMI, X86::PCMPEQDrr); break;
324 LowerSubReg32_Op0(OutMI, X86::MOV32r0); // MOV16r0 -> MOV32r0
325 LowerUnaryToTwoAddr(OutMI, X86::XOR32rr); // MOV32r0 -> XOR32rr
328 LowerSubReg32_Op0(OutMI, X86::MOV32r0); // MOV64r0 -> MOV32r0
329 LowerUnaryToTwoAddr(OutMI, X86::XOR32rr); // MOV32r0 -> XOR32rr
336 void X86AsmPrinter::EmitInstruction(const MachineInstr *MI) {
337 X86MCInstLower MCInstLowering(OutContext, Mang, *this);
338 switch (MI->getOpcode()) {
339 case TargetInstrInfo::DEBUG_VALUE: {
340 // FIXME: if this is implemented for another target before it goes
341 // away completely, the common part should be moved into AsmPrinter.
344 O << '\t' << MAI->getCommentString() << "DEBUG_VALUE: ";
345 unsigned NOps = MI->getNumOperands();
346 // cast away const; DIetc do not take const operands for some reason.
347 DIVariable V((MDNode*)(MI->getOperand(NOps-1).getMetadata()));
351 // Register or immediate value. Register 0 means undef.
352 assert(MI->getOperand(0).getType()==MachineOperand::MO_Register ||
353 MI->getOperand(0).getType()==MachineOperand::MO_Immediate ||
354 MI->getOperand(0).getType()==MachineOperand::MO_FPImmediate);
355 if (MI->getOperand(0).getType()==MachineOperand::MO_Register &&
356 MI->getOperand(0).getReg()==0) {
357 // Suppress offset in this case, it is not meaningful.
360 } else if (MI->getOperand(0).getType()==MachineOperand::MO_FPImmediate) {
361 // This is more naturally done in printOperand, but since the only use
362 // of such an operand is in this comment and that is temporary (and it's
363 // ugly), we prefer to keep this localized.
364 // The include of Type.h may be removable when this code is.
365 if (MI->getOperand(0).getFPImm()->getType()->isFloatTy() ||
366 MI->getOperand(0).getFPImm()->getType()->isDoubleTy())
367 MI->getOperand(0).print(O, &TM);
369 // There is no good way to print long double. Convert a copy to
370 // double. Ah well, it's only a comment.
372 APFloat APF = APFloat(MI->getOperand(0).getFPImm()->getValueAPF());
373 APF.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
375 O << "(long double) " << APF.convertToDouble();
380 // Frame address. Currently handles register +- offset only.
381 assert(MI->getOperand(0).getType()==MachineOperand::MO_Register);
382 assert(MI->getOperand(3).getType()==MachineOperand::MO_Immediate);
383 O << '['; printOperand(MI, 0); O << '+'; printOperand(MI, 3); O << ']';
386 printOperand(MI, NOps-2);
390 case X86::MOVPC32r: {
392 // This is a pseudo op for a two instruction sequence with a label, which
399 MCSymbol *PICBase = MCInstLowering.GetPICBaseSymbol();
400 TmpInst.setOpcode(X86::CALLpcrel32);
401 // FIXME: We would like an efficient form for this, so we don't have to do a
402 // lot of extra uniquing.
403 TmpInst.addOperand(MCOperand::CreateExpr(MCSymbolRefExpr::Create(PICBase,
405 OutStreamer.EmitInstruction(TmpInst);
408 OutStreamer.EmitLabel(PICBase);
411 TmpInst.setOpcode(X86::POP32r);
412 TmpInst.getOperand(0) = MCOperand::CreateReg(MI->getOperand(0).getReg());
413 OutStreamer.EmitInstruction(TmpInst);
418 // Lower the MO_GOT_ABSOLUTE_ADDRESS form of ADD32ri.
419 if (MI->getOperand(2).getTargetFlags() != X86II::MO_GOT_ABSOLUTE_ADDRESS)
422 // Okay, we have something like:
423 // EAX = ADD32ri EAX, MO_GOT_ABSOLUTE_ADDRESS(@MYGLOBAL)
425 // For this, we want to print something like:
426 // MYGLOBAL + (. - PICBASE)
427 // However, we can't generate a ".", so just emit a new label here and refer
428 // to it. We know that this operand flag occurs at most once per function.
429 const char *Prefix = MAI->getPrivateGlobalPrefix();
430 MCSymbol *DotSym = OutContext.GetOrCreateSymbol(Twine(Prefix)+"picbaseref"+
431 Twine(getFunctionNumber()));
432 OutStreamer.EmitLabel(DotSym);
434 // Now that we have emitted the label, lower the complex operand expression.
435 MCSymbol *OpSym = MCInstLowering.GetExternalSymbolSymbol(MI->getOperand(2));
437 const MCExpr *DotExpr = MCSymbolRefExpr::Create(DotSym, OutContext);
438 const MCExpr *PICBase =
439 MCSymbolRefExpr::Create(MCInstLowering.GetPICBaseSymbol(), OutContext);
440 DotExpr = MCBinaryExpr::CreateSub(DotExpr, PICBase, OutContext);
442 DotExpr = MCBinaryExpr::CreateAdd(MCSymbolRefExpr::Create(OpSym,OutContext),
443 DotExpr, OutContext);
446 TmpInst.setOpcode(X86::ADD32ri);
447 TmpInst.addOperand(MCOperand::CreateReg(MI->getOperand(0).getReg()));
448 TmpInst.addOperand(MCOperand::CreateReg(MI->getOperand(1).getReg()));
449 TmpInst.addOperand(MCOperand::CreateExpr(DotExpr));
450 OutStreamer.EmitInstruction(TmpInst);
456 MCInstLowering.Lower(MI, TmpInst);
459 OutStreamer.EmitInstruction(TmpInst);