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Diffstat (limited to 'contrib/llvm/lib/CodeGen/CallingConvLower.cpp')
-rw-r--r-- | contrib/llvm/lib/CodeGen/CallingConvLower.cpp | 249 |
1 files changed, 249 insertions, 0 deletions
diff --git a/contrib/llvm/lib/CodeGen/CallingConvLower.cpp b/contrib/llvm/lib/CodeGen/CallingConvLower.cpp new file mode 100644 index 0000000..034ffb3 --- /dev/null +++ b/contrib/llvm/lib/CodeGen/CallingConvLower.cpp @@ -0,0 +1,249 @@ +//===-- CallingConvLower.cpp - Calling Conventions ------------------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file implements the CCState class, used for lowering and implementing +// calling conventions. +// +//===----------------------------------------------------------------------===// + +#include "llvm/CodeGen/CallingConvLower.h" +#include "llvm/CodeGen/MachineFrameInfo.h" +#include "llvm/CodeGen/MachineRegisterInfo.h" +#include "llvm/IR/DataLayout.h" +#include "llvm/Support/Debug.h" +#include "llvm/Support/ErrorHandling.h" +#include "llvm/Support/SaveAndRestore.h" +#include "llvm/Support/raw_ostream.h" +#include "llvm/Target/TargetLowering.h" +#include "llvm/Target/TargetRegisterInfo.h" +#include "llvm/Target/TargetSubtargetInfo.h" +using namespace llvm; + +CCState::CCState(CallingConv::ID CC, bool isVarArg, MachineFunction &mf, + SmallVectorImpl<CCValAssign> &locs, LLVMContext &C) + : CallingConv(CC), IsVarArg(isVarArg), MF(mf), + TRI(*MF.getSubtarget().getRegisterInfo()), Locs(locs), Context(C), + CallOrPrologue(Unknown) { + // No stack is used. + StackOffset = 0; + + clearByValRegsInfo(); + UsedRegs.resize((TRI.getNumRegs()+31)/32); +} + +// HandleByVal - Allocate space on the stack large enough to pass an argument +// by value. The size and alignment information of the argument is encoded in +// its parameter attribute. +void CCState::HandleByVal(unsigned ValNo, MVT ValVT, + MVT LocVT, CCValAssign::LocInfo LocInfo, + int MinSize, int MinAlign, + ISD::ArgFlagsTy ArgFlags) { + unsigned Align = ArgFlags.getByValAlign(); + unsigned Size = ArgFlags.getByValSize(); + if (MinSize > (int)Size) + Size = MinSize; + if (MinAlign > (int)Align) + Align = MinAlign; + MF.getFrameInfo()->ensureMaxAlignment(Align); + MF.getSubtarget().getTargetLowering()->HandleByVal(this, Size, Align); + Size = unsigned(RoundUpToAlignment(Size, MinAlign)); + unsigned Offset = AllocateStack(Size, Align); + addLoc(CCValAssign::getMem(ValNo, ValVT, Offset, LocVT, LocInfo)); +} + +/// MarkAllocated - Mark a register and all of its aliases as allocated. +void CCState::MarkAllocated(unsigned Reg) { + for (MCRegAliasIterator AI(Reg, &TRI, true); AI.isValid(); ++AI) + UsedRegs[*AI/32] |= 1 << (*AI&31); +} + +/// AnalyzeFormalArguments - Analyze an array of argument values, +/// incorporating info about the formals into this state. +void +CCState::AnalyzeFormalArguments(const SmallVectorImpl<ISD::InputArg> &Ins, + CCAssignFn Fn) { + unsigned NumArgs = Ins.size(); + + for (unsigned i = 0; i != NumArgs; ++i) { + MVT ArgVT = Ins[i].VT; + ISD::ArgFlagsTy ArgFlags = Ins[i].Flags; + if (Fn(i, ArgVT, ArgVT, CCValAssign::Full, ArgFlags, *this)) { +#ifndef NDEBUG + dbgs() << "Formal argument #" << i << " has unhandled type " + << EVT(ArgVT).getEVTString() << '\n'; +#endif + llvm_unreachable(nullptr); + } + } +} + +/// CheckReturn - Analyze the return values of a function, returning true if +/// the return can be performed without sret-demotion, and false otherwise. +bool CCState::CheckReturn(const SmallVectorImpl<ISD::OutputArg> &Outs, + CCAssignFn Fn) { + // Determine which register each value should be copied into. + for (unsigned i = 0, e = Outs.size(); i != e; ++i) { + MVT VT = Outs[i].VT; + ISD::ArgFlagsTy ArgFlags = Outs[i].Flags; + if (Fn(i, VT, VT, CCValAssign::Full, ArgFlags, *this)) + return false; + } + return true; +} + +/// AnalyzeReturn - Analyze the returned values of a return, +/// incorporating info about the result values into this state. +void CCState::AnalyzeReturn(const SmallVectorImpl<ISD::OutputArg> &Outs, + CCAssignFn Fn) { + // Determine which register each value should be copied into. + for (unsigned i = 0, e = Outs.size(); i != e; ++i) { + MVT VT = Outs[i].VT; + ISD::ArgFlagsTy ArgFlags = Outs[i].Flags; + if (Fn(i, VT, VT, CCValAssign::Full, ArgFlags, *this)) { +#ifndef NDEBUG + dbgs() << "Return operand #" << i << " has unhandled type " + << EVT(VT).getEVTString() << '\n'; +#endif + llvm_unreachable(nullptr); + } + } +} + +/// AnalyzeCallOperands - Analyze the outgoing arguments to a call, +/// incorporating info about the passed values into this state. +void CCState::AnalyzeCallOperands(const SmallVectorImpl<ISD::OutputArg> &Outs, + CCAssignFn Fn) { + unsigned NumOps = Outs.size(); + for (unsigned i = 0; i != NumOps; ++i) { + MVT ArgVT = Outs[i].VT; + ISD::ArgFlagsTy ArgFlags = Outs[i].Flags; + if (Fn(i, ArgVT, ArgVT, CCValAssign::Full, ArgFlags, *this)) { +#ifndef NDEBUG + dbgs() << "Call operand #" << i << " has unhandled type " + << EVT(ArgVT).getEVTString() << '\n'; +#endif + llvm_unreachable(nullptr); + } + } +} + +/// AnalyzeCallOperands - Same as above except it takes vectors of types +/// and argument flags. +void CCState::AnalyzeCallOperands(SmallVectorImpl<MVT> &ArgVTs, + SmallVectorImpl<ISD::ArgFlagsTy> &Flags, + CCAssignFn Fn) { + unsigned NumOps = ArgVTs.size(); + for (unsigned i = 0; i != NumOps; ++i) { + MVT ArgVT = ArgVTs[i]; + ISD::ArgFlagsTy ArgFlags = Flags[i]; + if (Fn(i, ArgVT, ArgVT, CCValAssign::Full, ArgFlags, *this)) { +#ifndef NDEBUG + dbgs() << "Call operand #" << i << " has unhandled type " + << EVT(ArgVT).getEVTString() << '\n'; +#endif + llvm_unreachable(nullptr); + } + } +} + +/// AnalyzeCallResult - Analyze the return values of a call, +/// incorporating info about the passed values into this state. +void CCState::AnalyzeCallResult(const SmallVectorImpl<ISD::InputArg> &Ins, + CCAssignFn Fn) { + for (unsigned i = 0, e = Ins.size(); i != e; ++i) { + MVT VT = Ins[i].VT; + ISD::ArgFlagsTy Flags = Ins[i].Flags; + if (Fn(i, VT, VT, CCValAssign::Full, Flags, *this)) { +#ifndef NDEBUG + dbgs() << "Call result #" << i << " has unhandled type " + << EVT(VT).getEVTString() << '\n'; +#endif + llvm_unreachable(nullptr); + } + } +} + +/// AnalyzeCallResult - Same as above except it's specialized for calls which +/// produce a single value. +void CCState::AnalyzeCallResult(MVT VT, CCAssignFn Fn) { + if (Fn(0, VT, VT, CCValAssign::Full, ISD::ArgFlagsTy(), *this)) { +#ifndef NDEBUG + dbgs() << "Call result has unhandled type " + << EVT(VT).getEVTString() << '\n'; +#endif + llvm_unreachable(nullptr); + } +} + +static bool isValueTypeInRegForCC(CallingConv::ID CC, MVT VT) { + if (VT.isVector()) + return true; // Assume -msse-regparm might be in effect. + if (!VT.isInteger()) + return false; + if (CC == CallingConv::X86_VectorCall || CC == CallingConv::X86_FastCall) + return true; + return false; +} + +void CCState::getRemainingRegParmsForType(SmallVectorImpl<MCPhysReg> &Regs, + MVT VT, CCAssignFn Fn) { + unsigned SavedStackOffset = StackOffset; + unsigned NumLocs = Locs.size(); + + // Set the 'inreg' flag if it is used for this calling convention. + ISD::ArgFlagsTy Flags; + if (isValueTypeInRegForCC(CallingConv, VT)) + Flags.setInReg(); + + // Allocate something of this value type repeatedly until we get assigned a + // location in memory. + bool HaveRegParm = true; + while (HaveRegParm) { + if (Fn(0, VT, VT, CCValAssign::Full, Flags, *this)) { +#ifndef NDEBUG + dbgs() << "Call has unhandled type " << EVT(VT).getEVTString() + << " while computing remaining regparms\n"; +#endif + llvm_unreachable(nullptr); + } + HaveRegParm = Locs.back().isRegLoc(); + } + + // Copy all the registers from the value locations we added. + assert(NumLocs < Locs.size() && "CC assignment failed to add location"); + for (unsigned I = NumLocs, E = Locs.size(); I != E; ++I) + if (Locs[I].isRegLoc()) + Regs.push_back(MCPhysReg(Locs[I].getLocReg())); + + // Clear the assigned values and stack memory. We leave the registers marked + // as allocated so that future queries don't return the same registers, i.e. + // when i64 and f64 are both passed in GPRs. + StackOffset = SavedStackOffset; + Locs.resize(NumLocs); +} + +void CCState::analyzeMustTailForwardedRegisters( + SmallVectorImpl<ForwardedRegister> &Forwards, ArrayRef<MVT> RegParmTypes, + CCAssignFn Fn) { + // Oftentimes calling conventions will not user register parameters for + // variadic functions, so we need to assume we're not variadic so that we get + // all the registers that might be used in a non-variadic call. + SaveAndRestore<bool> SavedVarArg(IsVarArg, false); + + for (MVT RegVT : RegParmTypes) { + SmallVector<MCPhysReg, 8> RemainingRegs; + getRemainingRegParmsForType(RemainingRegs, RegVT, Fn); + const TargetLowering *TL = MF.getSubtarget().getTargetLowering(); + const TargetRegisterClass *RC = TL->getRegClassFor(RegVT); + for (MCPhysReg PReg : RemainingRegs) { + unsigned VReg = MF.addLiveIn(PReg, RC); + Forwards.push_back(ForwardedRegister(VReg, PReg, RegVT)); + } + } +} |