llvm-project/llvm/lib/Target/PowerPC/PPCMachineFunctionInfo.cpp
Matt Arsenault 69e75ae695 CodeGen: Don't lazily construct MachineFunctionInfo
This fixes what I consider to be an API flaw I've tripped over
multiple times. The point this is constructed isn't well defined, so
depending on where this is first called, you can conclude different
information based on the MachineFunction. For example, the AMDGPU
implementation inspected the MachineFrameInfo on construction for the
stack objects and if the frame has calls. This kind of worked in
SelectionDAG which visited all allocas up front, but broke in
GlobalISel which hasn't visited any of the IR when arguments are
lowered.

I've run into similar problems before with the MIR parser and trying
to make use of other MachineFunction fields, so I think it's best to
just categorically disallow dependency on the MachineFunction state in
the constructor and to always construct this at the same time as the
MachineFunction itself.

A missing feature I still could use is a way to access an custom
analysis pass on the IR here.
2022-12-21 10:49:32 -05:00

196 lines
6.6 KiB
C++

//===-- PPCMachineFunctionInfo.cpp - Private data used for PowerPC --------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "PPCMachineFunctionInfo.h"
#include "llvm/ADT/Twine.h"
#include "llvm/BinaryFormat/XCOFF.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/MC/MCContext.h"
#include "llvm/Support/CommandLine.h"
using namespace llvm;
static cl::opt<bool> PPCDisableNonVolatileCR(
"ppc-disable-non-volatile-cr",
cl::desc("Disable the use of non-volatile CR register fields"),
cl::init(false), cl::Hidden);
void PPCFunctionInfo::anchor() {}
PPCFunctionInfo::PPCFunctionInfo(const Function &F,
const TargetSubtargetInfo *STI)
: DisableNonVolatileCR(PPCDisableNonVolatileCR) {}
MachineFunctionInfo *
PPCFunctionInfo::clone(BumpPtrAllocator &Allocator, MachineFunction &DestMF,
const DenseMap<MachineBasicBlock *, MachineBasicBlock *>
&Src2DstMBB) const {
return DestMF.cloneInfo<PPCFunctionInfo>(*this);
}
MCSymbol *PPCFunctionInfo::getPICOffsetSymbol(MachineFunction &MF) const {
const DataLayout &DL = MF.getDataLayout();
return MF.getContext().getOrCreateSymbol(Twine(DL.getPrivateGlobalPrefix()) +
Twine(MF.getFunctionNumber()) +
"$poff");
}
MCSymbol *PPCFunctionInfo::getGlobalEPSymbol(MachineFunction &MF) const {
const DataLayout &DL = MF.getDataLayout();
return MF.getContext().getOrCreateSymbol(Twine(DL.getPrivateGlobalPrefix()) +
"func_gep" +
Twine(MF.getFunctionNumber()));
}
MCSymbol *PPCFunctionInfo::getLocalEPSymbol(MachineFunction &MF) const {
const DataLayout &DL = MF.getDataLayout();
return MF.getContext().getOrCreateSymbol(Twine(DL.getPrivateGlobalPrefix()) +
"func_lep" +
Twine(MF.getFunctionNumber()));
}
MCSymbol *PPCFunctionInfo::getTOCOffsetSymbol(MachineFunction &MF) const {
const DataLayout &DL = MF.getDataLayout();
return MF.getContext().getOrCreateSymbol(Twine(DL.getPrivateGlobalPrefix()) +
"func_toc" +
Twine(MF.getFunctionNumber()));
}
bool PPCFunctionInfo::isLiveInSExt(Register VReg) const {
for (const std::pair<Register, ISD::ArgFlagsTy> &LiveIn : LiveInAttrs)
if (LiveIn.first == VReg)
return LiveIn.second.isSExt();
return false;
}
bool PPCFunctionInfo::isLiveInZExt(Register VReg) const {
for (const std::pair<Register, ISD::ArgFlagsTy> &LiveIn : LiveInAttrs)
if (LiveIn.first == VReg)
return LiveIn.second.isZExt();
return false;
}
void PPCFunctionInfo::appendParameterType(ParamType Type) {
ParamtersType.push_back(Type);
switch (Type) {
case FixedType:
++FixedParmsNum;
return;
case ShortFloatingPoint:
case LongFloatingPoint:
++FloatingParmsNum;
return;
case VectorChar:
case VectorShort:
case VectorInt:
case VectorFloat:
++VectorParmsNum;
return;
}
llvm_unreachable("Error ParamType type.");
}
uint32_t PPCFunctionInfo::getVecExtParmsType() const {
uint32_t VectExtParamInfo = 0;
unsigned ShiftBits = 32 - XCOFF::TracebackTable::WidthOfParamType;
int Bits = 0;
if (!hasVectorParms())
return 0;
for (const auto &Elt : ParamtersType) {
switch (Elt) {
case VectorChar:
VectExtParamInfo <<= XCOFF::TracebackTable::WidthOfParamType;
VectExtParamInfo |=
XCOFF::TracebackTable::ParmTypeIsVectorCharBit >> ShiftBits;
Bits += XCOFF::TracebackTable::WidthOfParamType;
break;
case VectorShort:
VectExtParamInfo <<= XCOFF::TracebackTable::WidthOfParamType;
VectExtParamInfo |=
XCOFF::TracebackTable::ParmTypeIsVectorShortBit >> ShiftBits;
Bits += XCOFF::TracebackTable::WidthOfParamType;
break;
case VectorInt:
VectExtParamInfo <<= XCOFF::TracebackTable::WidthOfParamType;
VectExtParamInfo |=
XCOFF::TracebackTable::ParmTypeIsVectorIntBit >> ShiftBits;
Bits += XCOFF::TracebackTable::WidthOfParamType;
break;
case VectorFloat:
VectExtParamInfo <<= XCOFF::TracebackTable::WidthOfParamType;
VectExtParamInfo |=
XCOFF::TracebackTable::ParmTypeIsVectorFloatBit >> ShiftBits;
Bits += XCOFF::TracebackTable::WidthOfParamType;
break;
default:
break;
}
// There are only 32bits in the VectExtParamInfo.
if (Bits >= 32)
break;
}
return Bits < 32 ? VectExtParamInfo << (32 - Bits) : VectExtParamInfo;
}
uint32_t PPCFunctionInfo::getParmsType() const {
uint32_t ParamsTypeInfo = 0;
unsigned ShiftBits = 32 - XCOFF::TracebackTable::WidthOfParamType;
int Bits = 0;
for (const auto &Elt : ParamtersType) {
if (Bits > 31 || (Bits > 30 && (Elt != FixedType || hasVectorParms())))
break;
switch (Elt) {
case FixedType:
if (hasVectorParms()) {
//'00' ==> fixed parameter if HasVectorParms is true.
ParamsTypeInfo <<= XCOFF::TracebackTable::WidthOfParamType;
ParamsTypeInfo |=
XCOFF::TracebackTable::ParmTypeIsFixedBits >> ShiftBits;
Bits += XCOFF::TracebackTable::WidthOfParamType;
} else {
//'0' ==> fixed parameter if HasVectorParms is false.
ParamsTypeInfo <<= 1;
++Bits;
}
break;
case ShortFloatingPoint:
// '10'b => floating point short parameter.
ParamsTypeInfo <<= XCOFF::TracebackTable::WidthOfParamType;
ParamsTypeInfo |=
XCOFF::TracebackTable::ParmTypeIsFloatingBits >> ShiftBits;
Bits += XCOFF::TracebackTable::WidthOfParamType;
break;
case LongFloatingPoint:
// '11'b => floating point long parameter.
ParamsTypeInfo <<= XCOFF::TracebackTable::WidthOfParamType;
ParamsTypeInfo |=
XCOFF::TracebackTable::ParmTypeIsDoubleBits >> ShiftBits;
Bits += XCOFF::TracebackTable::WidthOfParamType;
break;
case VectorChar:
case VectorShort:
case VectorInt:
case VectorFloat:
// '01' ==> vector parameter
ParamsTypeInfo <<= XCOFF::TracebackTable::WidthOfParamType;
ParamsTypeInfo |=
XCOFF::TracebackTable::ParmTypeIsVectorBits >> ShiftBits;
Bits += XCOFF::TracebackTable::WidthOfParamType;
break;
}
}
return Bits < 32 ? ParamsTypeInfo << (32 - Bits) : ParamsTypeInfo;
}