diff options
Diffstat (limited to 'llvm/lib')
-rw-r--r-- | llvm/lib/Target/X86/X86CallLowering.cpp | 180 | ||||
-rw-r--r-- | llvm/lib/Target/X86/X86CallLowering.h | 4 |
2 files changed, 171 insertions, 13 deletions
diff --git a/llvm/lib/Target/X86/X86CallLowering.cpp b/llvm/lib/Target/X86/X86CallLowering.cpp index c8a3b2b51c8..cbe9e60864d 100644 --- a/llvm/lib/Target/X86/X86CallLowering.cpp +++ b/llvm/lib/Target/X86/X86CallLowering.cpp @@ -21,6 +21,7 @@ #include "llvm/CodeGen/Analysis.h" #include "llvm/CodeGen/GlobalISel/MachineIRBuilder.h" +#include "llvm/CodeGen/GlobalISel/Utils.h" #include "llvm/CodeGen/MachineRegisterInfo.h" #include "llvm/CodeGen/MachineValueType.h" #include "llvm/Target/TargetSubtargetInfo.h" @@ -78,14 +79,29 @@ bool X86CallLowering::splitToValueTypes(const ArgInfo &OrigArg, } namespace { -struct FuncReturnHandler : public CallLowering::ValueHandler { - FuncReturnHandler(MachineIRBuilder &MIRBuilder, MachineRegisterInfo &MRI, - MachineInstrBuilder &MIB, CCAssignFn *AssignFn) - : ValueHandler(MIRBuilder, MRI, AssignFn), MIB(MIB) {} +struct OutgoingValueHandler : public CallLowering::ValueHandler { + OutgoingValueHandler(MachineIRBuilder &MIRBuilder, MachineRegisterInfo &MRI, + MachineInstrBuilder &MIB, CCAssignFn *AssignFn) + : ValueHandler(MIRBuilder, MRI, AssignFn), MIB(MIB), StackSize(0), + DL(MIRBuilder.getMF().getDataLayout()), + STI(MIRBuilder.getMF().getSubtarget<X86Subtarget>()) {} unsigned getStackAddress(uint64_t Size, int64_t Offset, MachinePointerInfo &MPO) override { - llvm_unreachable("Don't know how to get a stack address yet"); + + LLT p0 = LLT::pointer(0, DL.getPointerSizeInBits(0)); + LLT SType = LLT::scalar(DL.getPointerSizeInBits(0)); + unsigned SPReg = MRI.createGenericVirtualRegister(p0); + MIRBuilder.buildCopy(SPReg, STI.getRegisterInfo()->getStackRegister()); + + unsigned OffsetReg = MRI.createGenericVirtualRegister(SType); + MIRBuilder.buildConstant(OffsetReg, Offset); + + unsigned AddrReg = MRI.createGenericVirtualRegister(p0); + MIRBuilder.buildGEP(AddrReg, SPReg, OffsetReg); + + MPO = MachinePointerInfo::getStack(MIRBuilder.getMF(), Offset); + return AddrReg; } void assignValueToReg(unsigned ValVReg, unsigned PhysReg, @@ -97,10 +113,33 @@ struct FuncReturnHandler : public CallLowering::ValueHandler { void assignValueToAddress(unsigned ValVReg, unsigned Addr, uint64_t Size, MachinePointerInfo &MPO, CCValAssign &VA) override { - llvm_unreachable("Don't know how to assign a value to an address yet"); + + unsigned ExtReg = extendRegister(ValVReg, VA); + auto MMO = MIRBuilder.getMF().getMachineMemOperand( + MPO, MachineMemOperand::MOStore, VA.getLocVT().getStoreSize(), + /* Alignment */ 0); + MIRBuilder.buildStore(ExtReg, Addr, *MMO); } + bool assignArg(unsigned ValNo, MVT ValVT, MVT LocVT, + CCValAssign::LocInfo LocInfo, + const CallLowering::ArgInfo &Info, CCState &State) override { + + if (!Info.IsFixed) + return true; // TODO: handle variadic function + + bool Res = AssignFn(ValNo, ValVT, LocVT, LocInfo, Info.Flags, State); + StackSize = State.getNextStackOffset(); + return Res; + } + + uint64_t getStackSize() { return StackSize; } + +protected: MachineInstrBuilder &MIB; + uint64_t StackSize; + const DataLayout &DL; + const X86Subtarget &STI; }; } // End anonymous namespace. @@ -127,7 +166,7 @@ bool X86CallLowering::lowerReturn(MachineIRBuilder &MIRBuilder, })) return false; - FuncReturnHandler Handler(MIRBuilder, MRI, MIB, RetCC_X86); + OutgoingValueHandler Handler(MIRBuilder, MRI, MIB, RetCC_X86); if (!handleAssignments(MIRBuilder, SplitArgs, Handler)) return false; } @@ -137,10 +176,11 @@ bool X86CallLowering::lowerReturn(MachineIRBuilder &MIRBuilder, } namespace { -struct FormalArgHandler : public CallLowering::ValueHandler { - FormalArgHandler(MachineIRBuilder &MIRBuilder, MachineRegisterInfo &MRI, - CCAssignFn *AssignFn, const DataLayout &DL) - : ValueHandler(MIRBuilder, MRI, AssignFn), DL(DL) {} +struct IncomingValueHandler : public CallLowering::ValueHandler { + IncomingValueHandler(MachineIRBuilder &MIRBuilder, MachineRegisterInfo &MRI, + CCAssignFn *AssignFn) + : ValueHandler(MIRBuilder, MRI, AssignFn), + DL(MIRBuilder.getMF().getDataLayout()) {} unsigned getStackAddress(uint64_t Size, int64_t Offset, MachinePointerInfo &MPO) override { @@ -164,14 +204,37 @@ struct FormalArgHandler : public CallLowering::ValueHandler { MIRBuilder.buildLoad(ValVReg, Addr, *MMO); } +protected: + const DataLayout &DL; +}; + +struct FormalArgHandler : public IncomingValueHandler { + FormalArgHandler(MachineIRBuilder &MIRBuilder, MachineRegisterInfo &MRI, + CCAssignFn *AssignFn) + : IncomingValueHandler(MIRBuilder, MRI, AssignFn) {} + void assignValueToReg(unsigned ValVReg, unsigned PhysReg, CCValAssign &VA) override { MIRBuilder.getMBB().addLiveIn(PhysReg); MIRBuilder.buildCopy(ValVReg, PhysReg); } +}; - const DataLayout &DL; +struct CallReturnHandler : public IncomingValueHandler { + CallReturnHandler(MachineIRBuilder &MIRBuilder, MachineRegisterInfo &MRI, + CCAssignFn *AssignFn, MachineInstrBuilder &MIB) + : IncomingValueHandler(MIRBuilder, MRI, AssignFn), MIB(MIB) {} + + void assignValueToReg(unsigned ValVReg, unsigned PhysReg, + CCValAssign &VA) override { + MIB.addDef(PhysReg, RegState::Implicit); + MIRBuilder.buildCopy(ValVReg, PhysReg); + } + +protected: + MachineInstrBuilder &MIB; }; + } // namespace bool X86CallLowering::lowerFormalArguments(MachineIRBuilder &MIRBuilder, @@ -215,7 +278,7 @@ bool X86CallLowering::lowerFormalArguments(MachineIRBuilder &MIRBuilder, if (!MBB.empty()) MIRBuilder.setInstr(*MBB.begin()); - FormalArgHandler Handler(MIRBuilder, MRI, CC_X86, DL); + FormalArgHandler Handler(MIRBuilder, MRI, CC_X86); if (!handleAssignments(MIRBuilder, SplitArgs, Handler)) return false; @@ -224,3 +287,94 @@ bool X86CallLowering::lowerFormalArguments(MachineIRBuilder &MIRBuilder, return true; } + +bool X86CallLowering::lowerCall(MachineIRBuilder &MIRBuilder, + CallingConv::ID CallConv, + const MachineOperand &Callee, + const ArgInfo &OrigRet, + ArrayRef<ArgInfo> OrigArgs) const { + + MachineFunction &MF = MIRBuilder.getMF(); + const Function &F = *MF.getFunction(); + MachineRegisterInfo &MRI = MF.getRegInfo(); + auto &DL = F.getParent()->getDataLayout(); + const X86Subtarget &STI = MF.getSubtarget<X86Subtarget>(); + const TargetInstrInfo &TII = *STI.getInstrInfo(); + auto TRI = STI.getRegisterInfo(); + + // Handle only Linux C, X86_64_SysV calling conventions for now. + if (!STI.isTargetLinux() || + !(CallConv == CallingConv::C || CallConv == CallingConv::X86_64_SysV)) + return false; + + unsigned AdjStackDown = TII.getCallFrameSetupOpcode(); + auto CallSeqStart = MIRBuilder.buildInstr(AdjStackDown); + + // Create a temporarily-floating call instruction so we can add the implicit + // uses of arg registers. + bool Is64Bit = STI.is64Bit(); + unsigned CallOpc = Callee.isReg() + ? (Is64Bit ? X86::CALL64r : X86::CALL32r) + : (Is64Bit ? X86::CALL64pcrel32 : X86::CALLpcrel32); + + auto MIB = MIRBuilder.buildInstrNoInsert(CallOpc).add(Callee).addRegMask( + TRI->getCallPreservedMask(MF, CallConv)); + + SmallVector<ArgInfo, 8> SplitArgs; + for (const auto &OrigArg : OrigArgs) { + if (!splitToValueTypes(OrigArg, SplitArgs, DL, MRI, + [&](ArrayRef<unsigned> Regs) { + MIRBuilder.buildUnmerge(Regs, OrigArg.Reg); + })) + return false; + } + // Do the actual argument marshalling. + OutgoingValueHandler Handler(MIRBuilder, MRI, MIB, CC_X86); + if (!handleAssignments(MIRBuilder, SplitArgs, Handler)) + return false; + + // Now we can add the actual call instruction to the correct basic block. + MIRBuilder.insertInstr(MIB); + + // If Callee is a reg, since it is used by a target specific + // instruction, it must have a register class matching the + // constraint of that instruction. + if (Callee.isReg()) + MIB->getOperand(0).setReg(constrainOperandRegClass( + MF, *TRI, MRI, *MF.getSubtarget().getInstrInfo(), + *MF.getSubtarget().getRegBankInfo(), *MIB, MIB->getDesc(), + Callee.getReg(), 0)); + + // Finally we can copy the returned value back into its virtual-register. In + // symmetry with the arguments, the physical register must be an + // implicit-define of the call instruction. + + if (OrigRet.Reg) { + SplitArgs.clear(); + SmallVector<unsigned, 8> NewRegs; + + if (!splitToValueTypes(OrigRet, SplitArgs, DL, MRI, + [&](ArrayRef<unsigned> Regs) { + NewRegs.assign(Regs.begin(), Regs.end()); + })) + return false; + + CallReturnHandler Handler(MIRBuilder, MRI, RetCC_X86, MIB); + if (!handleAssignments(MIRBuilder, SplitArgs, Handler)) + return false; + + if (!NewRegs.empty()) + MIRBuilder.buildMerge(OrigRet.Reg, NewRegs); + } + + CallSeqStart.addImm(Handler.getStackSize()) + .addImm(0 /* see getFrameTotalSize */) + .addImm(0 /* see getFrameAdjustment */); + + unsigned AdjStackUp = TII.getCallFrameDestroyOpcode(); + MIRBuilder.buildInstr(AdjStackUp) + .addImm(Handler.getStackSize()) + .addImm(0 /* NumBytesForCalleeToPop */); + + return true; +} diff --git a/llvm/lib/Target/X86/X86CallLowering.h b/llvm/lib/Target/X86/X86CallLowering.h index 6a5dabf33a0..f8f83717586 100644 --- a/llvm/lib/Target/X86/X86CallLowering.h +++ b/llvm/lib/Target/X86/X86CallLowering.h @@ -35,6 +35,10 @@ public: bool lowerFormalArguments(MachineIRBuilder &MIRBuilder, const Function &F, ArrayRef<unsigned> VRegs) const override; + bool lowerCall(MachineIRBuilder &MIRBuilder, CallingConv::ID CallConv, + const MachineOperand &Callee, const ArgInfo &OrigRet, + ArrayRef<ArgInfo> OrigArgs) const override; + private: /// A function of this type is used to perform value split action. typedef std::function<void(ArrayRef<unsigned>)> SplitArgTy; |