X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FTarget%2FX86%2FX86FastISel.cpp;h=c5da0b9b164f6140f3d8c5b099bbef0686b4acb1;hb=b8f0d89d0584e37e205c04ed5753f57a23365403;hp=9d2dac2c9bd1152e1ecb5d3ac078306c731e5275;hpb=8b62abdd7b9c8fc5d78dad86093f4afdfeba949d;p=oota-llvm.git diff --git a/lib/Target/X86/X86FastISel.cpp b/lib/Target/X86/X86FastISel.cpp index 9d2dac2c9bd..c5da0b9b164 100644 --- a/lib/Target/X86/X86FastISel.cpp +++ b/lib/Target/X86/X86FastISel.cpp @@ -19,19 +19,19 @@ #include "X86RegisterInfo.h" #include "X86Subtarget.h" #include "X86TargetMachine.h" -#include "llvm/CallingConv.h" #include "llvm/CodeGen/Analysis.h" #include "llvm/CodeGen/FastISel.h" #include "llvm/CodeGen/FunctionLoweringInfo.h" #include "llvm/CodeGen/MachineConstantPool.h" #include "llvm/CodeGen/MachineFrameInfo.h" #include "llvm/CodeGen/MachineRegisterInfo.h" -#include "llvm/DerivedTypes.h" -#include "llvm/GlobalAlias.h" -#include "llvm/GlobalVariable.h" -#include "llvm/Instructions.h" -#include "llvm/IntrinsicInst.h" -#include "llvm/Operator.h" +#include "llvm/IR/CallingConv.h" +#include "llvm/IR/DerivedTypes.h" +#include "llvm/IR/GlobalAlias.h" +#include "llvm/IR/GlobalVariable.h" +#include "llvm/IR/Instructions.h" +#include "llvm/IR/IntrinsicInst.h" +#include "llvm/IR/Operator.h" #include "llvm/Support/CallSite.h" #include "llvm/Support/ErrorHandling.h" #include "llvm/Support/GetElementPtrTypeIterator.h" @@ -75,6 +75,8 @@ public: virtual bool TryToFoldLoad(MachineInstr *MI, unsigned OpNo, const LoadInst *LI); + virtual bool FastLowerArguments(); + #include "X86GenFastISel.inc" private: @@ -326,12 +328,11 @@ bool X86FastISel::X86FastEmitExtend(ISD::NodeType Opc, EVT DstVT, unsigned &ResultReg) { unsigned RR = FastEmit_r(SrcVT.getSimpleVT(), DstVT.getSimpleVT(), Opc, Src, /*TODO: Kill=*/false); - - if (RR != 0) { - ResultReg = RR; - return true; - } else + if (RR == 0) return false; + + ResultReg = RR; + return true; } /// X86SelectAddress - Attempt to fill in an address from the given value. @@ -727,7 +728,7 @@ bool X86FastISel::X86SelectRet(const Instruction *I) { // Don't handle popping bytes on return for now. if (X86MFInfo->getBytesToPopOnReturn() != 0) - return 0; + return false; // fastcc with -tailcallopt is intended to provide a guaranteed // tail call optimization. Fastisel doesn't know how to do that. @@ -738,6 +739,9 @@ bool X86FastISel::X86SelectRet(const Instruction *I) { if (F.isVarArg()) return false; + // Build a list of return value registers. + SmallVector RetRegs; + if (Ret->getNumOperands() > 0) { SmallVector Outs; GetReturnInfo(F.getReturnType(), F.getAttributes(), Outs, TLI); @@ -805,25 +809,30 @@ bool X86FastISel::X86SelectRet(const Instruction *I) { BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(TargetOpcode::COPY), DstReg).addReg(SrcReg); - // Mark the register as live out of the function. - MRI.addLiveOut(VA.getLocReg()); + // Add register to return instruction. + RetRegs.push_back(VA.getLocReg()); } // The x86-64 ABI for returning structs by value requires that we copy // the sret argument into %rax for the return. We saved the argument into // a virtual register in the entry block, so now we copy the value out - // and into %rax. - if (Subtarget->is64Bit() && F.hasStructRetAttr()) { + // and into %rax. We also do the same with %eax for Win32. + if (F.hasStructRetAttr() && + (Subtarget->is64Bit() || Subtarget->isTargetWindows())) { unsigned Reg = X86MFInfo->getSRetReturnReg(); assert(Reg && "SRetReturnReg should have been set in LowerFormalArguments()!"); + unsigned RetReg = Subtarget->is64Bit() ? X86::RAX : X86::EAX; BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(TargetOpcode::COPY), - X86::RAX).addReg(Reg); - MRI.addLiveOut(X86::RAX); + RetReg).addReg(Reg); + RetRegs.push_back(RetReg); } // Now emit the RET. - BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(X86::RET)); + MachineInstrBuilder MIB = + BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(X86::RET)); + for (unsigned i = 0, e = RetRegs.size(); i != e; ++i) + MIB.addReg(RetRegs[i], RegState::Implicit); return true; } @@ -1372,7 +1381,6 @@ bool X86FastISel::TryEmitSmallMemcpy(X86AddressMode DestAM, else if (Len >= 2) VT = MVT::i16; else { - assert(Len == 1); VT = MVT::i8; } @@ -1516,6 +1524,81 @@ bool X86FastISel::X86VisitIntrinsicCall(const IntrinsicInst &I) { } } +bool X86FastISel::FastLowerArguments() { + if (!FuncInfo.CanLowerReturn) + return false; + + if (Subtarget->isTargetWindows()) + return false; + + const Function *F = FuncInfo.Fn; + if (F->isVarArg()) + return false; + + CallingConv::ID CC = F->getCallingConv(); + if (CC != CallingConv::C) + return false; + + if (!Subtarget->is64Bit()) + return false; + + // Only handle simple cases. i.e. Up to 6 i32/i64 scalar arguments. + unsigned Idx = 1; + for (Function::const_arg_iterator I = F->arg_begin(), E = F->arg_end(); + I != E; ++I, ++Idx) { + if (Idx > 6) + return false; + + if (F->getAttributes().hasAttribute(Idx, Attribute::ByVal) || + F->getAttributes().hasAttribute(Idx, Attribute::InReg) || + F->getAttributes().hasAttribute(Idx, Attribute::StructRet) || + F->getAttributes().hasAttribute(Idx, Attribute::Nest)) + return false; + + Type *ArgTy = I->getType(); + if (ArgTy->isStructTy() || ArgTy->isArrayTy() || ArgTy->isVectorTy()) + return false; + + EVT ArgVT = TLI.getValueType(ArgTy); + if (!ArgVT.isSimple()) return false; + switch (ArgVT.getSimpleVT().SimpleTy) { + case MVT::i32: + case MVT::i64: + break; + default: + return false; + } + } + + static const uint16_t GPR32ArgRegs[] = { + X86::EDI, X86::ESI, X86::EDX, X86::ECX, X86::R8D, X86::R9D + }; + static const uint16_t GPR64ArgRegs[] = { + X86::RDI, X86::RSI, X86::RDX, X86::RCX, X86::R8 , X86::R9 + }; + + Idx = 0; + const TargetRegisterClass *RC32 = TLI.getRegClassFor(MVT::i32); + const TargetRegisterClass *RC64 = TLI.getRegClassFor(MVT::i64); + for (Function::const_arg_iterator I = F->arg_begin(), E = F->arg_end(); + I != E; ++I, ++Idx) { + if (I->use_empty()) + continue; + bool is32Bit = TLI.getValueType(I->getType()) == MVT::i32; + const TargetRegisterClass *RC = is32Bit ? RC32 : RC64; + unsigned SrcReg = is32Bit ? GPR32ArgRegs[Idx] : GPR64ArgRegs[Idx]; + unsigned DstReg = FuncInfo.MF->addLiveIn(SrcReg, RC); + // FIXME: Unfortunately it's necessary to emit a copy from the livein copy. + // Without this, EmitLiveInCopies may eliminate the livein if its only + // use is a bitcast (which isn't turned into an instruction). + unsigned ResultReg = createResultReg(RC); + BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(TargetOpcode::COPY), + ResultReg).addReg(DstReg, getKillRegState(true)); + UpdateValueMap(I, ResultReg); + } + return true; +} + bool X86FastISel::X86SelectCall(const Instruction *I) { const CallInst *CI = cast(I); const Value *Callee = CI->getCalledValue();