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//===- MemoryLocation.cpp - Memory location descriptions -------------------==//
//
// 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 "llvm/Analysis/MemoryLocation.h"
#include "llvm/Analysis/TargetLibraryInfo.h"
#include "llvm/IR/BasicBlock.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/IntrinsicsARM.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Type.h"
using namespace llvm;
void LocationSize::print(raw_ostream &OS) const {
OS << "LocationSize::";
if (*this == beforeOrAfterPointer())
OS << "beforeOrAfterPointer";
else if (*this == afterPointer())
OS << "afterPointer";
else if (*this == mapEmpty())
OS << "mapEmpty";
else if (*this == mapTombstone())
OS << "mapTombstone";
else if (isPrecise())
OS << "precise(" << getValue() << ')';
else
OS << "upperBound(" << getValue() << ')';
}
MemoryLocation MemoryLocation::get(const LoadInst *LI) {
AAMDNodes AATags;
LI->getAAMetadata(AATags);
const auto &DL = LI->getModule()->getDataLayout();
return MemoryLocation(
LI->getPointerOperand(),
LocationSize::precise(DL.getTypeStoreSize(LI->getType())), AATags);
}
MemoryLocation MemoryLocation::get(const StoreInst *SI) {
AAMDNodes AATags;
SI->getAAMetadata(AATags);
const auto &DL = SI->getModule()->getDataLayout();
return MemoryLocation(SI->getPointerOperand(),
LocationSize::precise(DL.getTypeStoreSize(
SI->getValueOperand()->getType())),
AATags);
}
MemoryLocation MemoryLocation::get(const VAArgInst *VI) {
AAMDNodes AATags;
VI->getAAMetadata(AATags);
return MemoryLocation(VI->getPointerOperand(),
LocationSize::afterPointer(), AATags);
}
MemoryLocation MemoryLocation::get(const AtomicCmpXchgInst *CXI) {
AAMDNodes AATags;
CXI->getAAMetadata(AATags);
const auto &DL = CXI->getModule()->getDataLayout();
return MemoryLocation(CXI->getPointerOperand(),
LocationSize::precise(DL.getTypeStoreSize(
CXI->getCompareOperand()->getType())),
AATags);
}
MemoryLocation MemoryLocation::get(const AtomicRMWInst *RMWI) {
AAMDNodes AATags;
RMWI->getAAMetadata(AATags);
const auto &DL = RMWI->getModule()->getDataLayout();
return MemoryLocation(RMWI->getPointerOperand(),
LocationSize::precise(DL.getTypeStoreSize(
RMWI->getValOperand()->getType())),
AATags);
}
Optional<MemoryLocation> MemoryLocation::getOrNone(const Instruction *Inst) {
switch (Inst->getOpcode()) {
case Instruction::Load:
return get(cast<LoadInst>(Inst));
case Instruction::Store:
return get(cast<StoreInst>(Inst));
case Instruction::VAArg:
return get(cast<VAArgInst>(Inst));
case Instruction::AtomicCmpXchg:
return get(cast<AtomicCmpXchgInst>(Inst));
case Instruction::AtomicRMW:
return get(cast<AtomicRMWInst>(Inst));
default:
return None;
}
}
MemoryLocation MemoryLocation::getForSource(const MemTransferInst *MTI) {
return getForSource(cast<AnyMemTransferInst>(MTI));
}
MemoryLocation MemoryLocation::getForSource(const AtomicMemTransferInst *MTI) {
return getForSource(cast<AnyMemTransferInst>(MTI));
}
MemoryLocation MemoryLocation::getForSource(const AnyMemTransferInst *MTI) {
auto Size = LocationSize::afterPointer();
if (ConstantInt *C = dyn_cast<ConstantInt>(MTI->getLength()))
Size = LocationSize::precise(C->getValue().getZExtValue());
// memcpy/memmove can have AA tags. For memcpy, they apply
// to both the source and the destination.
AAMDNodes AATags;
MTI->getAAMetadata(AATags);
return MemoryLocation(MTI->getRawSource(), Size, AATags);
}
MemoryLocation MemoryLocation::getForDest(const MemIntrinsic *MI) {
return getForDest(cast<AnyMemIntrinsic>(MI));
}
MemoryLocation MemoryLocation::getForDest(const AtomicMemIntrinsic *MI) {
return getForDest(cast<AnyMemIntrinsic>(MI));
}
MemoryLocation MemoryLocation::getForDest(const AnyMemIntrinsic *MI) {
auto Size = LocationSize::afterPointer();
if (ConstantInt *C = dyn_cast<ConstantInt>(MI->getLength()))
Size = LocationSize::precise(C->getValue().getZExtValue());
// memcpy/memmove can have AA tags. For memcpy, they apply
// to both the source and the destination.
AAMDNodes AATags;
MI->getAAMetadata(AATags);
return MemoryLocation(MI->getRawDest(), Size, AATags);
}
MemoryLocation MemoryLocation::getForArgument(const CallBase *Call,
unsigned ArgIdx,
const TargetLibraryInfo *TLI) {
AAMDNodes AATags;
Call->getAAMetadata(AATags);
const Value *Arg = Call->getArgOperand(ArgIdx);
// We may be able to produce an exact size for known intrinsics.
if (const IntrinsicInst *II = dyn_cast<IntrinsicInst>(Call)) {
const DataLayout &DL = II->getModule()->getDataLayout();
switch (II->getIntrinsicID()) {
default:
break;
case Intrinsic::memset:
case Intrinsic::memcpy:
case Intrinsic::memcpy_inline:
case Intrinsic::memmove:
assert((ArgIdx == 0 || ArgIdx == 1) &&
"Invalid argument index for memory intrinsic");
if (ConstantInt *LenCI = dyn_cast<ConstantInt>(II->getArgOperand(2)))
return MemoryLocation(Arg, LocationSize::precise(LenCI->getZExtValue()),
AATags);
return MemoryLocation::getAfter(Arg, AATags);
case Intrinsic::lifetime_start:
case Intrinsic::lifetime_end:
case Intrinsic::invariant_start:
assert(ArgIdx == 1 && "Invalid argument index");
return MemoryLocation(
Arg,
LocationSize::precise(
cast<ConstantInt>(II->getArgOperand(0))->getZExtValue()),
AATags);
case Intrinsic::masked_load:
assert(ArgIdx == 0 && "Invalid argument index");
return MemoryLocation(
Arg,
LocationSize::upperBound(DL.getTypeStoreSize(II->getType())),
AATags);
case Intrinsic::masked_store:
assert(ArgIdx == 1 && "Invalid argument index");
return MemoryLocation(
Arg,
LocationSize::upperBound(
DL.getTypeStoreSize(II->getArgOperand(0)->getType())),
AATags);
case Intrinsic::invariant_end:
// The first argument to an invariant.end is a "descriptor" type (e.g. a
// pointer to a empty struct) which is never actually dereferenced.
if (ArgIdx == 0)
return MemoryLocation(Arg, LocationSize::precise(0), AATags);
assert(ArgIdx == 2 && "Invalid argument index");
return MemoryLocation(
Arg,
LocationSize::precise(
cast<ConstantInt>(II->getArgOperand(1))->getZExtValue()),
AATags);
case Intrinsic::arm_neon_vld1:
assert(ArgIdx == 0 && "Invalid argument index");
// LLVM's vld1 and vst1 intrinsics currently only support a single
// vector register.
return MemoryLocation(
Arg, LocationSize::precise(DL.getTypeStoreSize(II->getType())),
AATags);
case Intrinsic::arm_neon_vst1:
assert(ArgIdx == 0 && "Invalid argument index");
return MemoryLocation(Arg,
LocationSize::precise(DL.getTypeStoreSize(
II->getArgOperand(1)->getType())),
AATags);
}
}
// We can bound the aliasing properties of memset_pattern16 just as we can
// for memcpy/memset. This is particularly important because the
// LoopIdiomRecognizer likes to turn loops into calls to memset_pattern16
// whenever possible.
LibFunc F;
if (TLI && TLI->getLibFunc(*Call, F) && TLI->has(F)) {
switch (F) {
case LibFunc_memset_pattern16:
assert((ArgIdx == 0 || ArgIdx == 1) &&
"Invalid argument index for memset_pattern16");
if (ArgIdx == 1)
return MemoryLocation(Arg, LocationSize::precise(16), AATags);
if (const ConstantInt *LenCI =
dyn_cast<ConstantInt>(Call->getArgOperand(2)))
return MemoryLocation(Arg, LocationSize::precise(LenCI->getZExtValue()),
AATags);
return MemoryLocation::getAfter(Arg, AATags);
case LibFunc_bcmp:
case LibFunc_memcmp:
assert((ArgIdx == 0 || ArgIdx == 1) &&
"Invalid argument index for memcmp/bcmp");
if (const ConstantInt *LenCI =
dyn_cast<ConstantInt>(Call->getArgOperand(2)))
return MemoryLocation(Arg, LocationSize::precise(LenCI->getZExtValue()),
AATags);
return MemoryLocation::getAfter(Arg, AATags);
case LibFunc_memchr:
assert((ArgIdx == 0) && "Invalid argument index for memchr");
if (const ConstantInt *LenCI =
dyn_cast<ConstantInt>(Call->getArgOperand(2)))
return MemoryLocation(Arg, LocationSize::precise(LenCI->getZExtValue()),
AATags);
return MemoryLocation::getAfter(Arg, AATags);
case LibFunc_memccpy:
assert((ArgIdx == 0 || ArgIdx == 1) &&
"Invalid argument index for memccpy");
// We only know an upper bound on the number of bytes read/written.
if (const ConstantInt *LenCI =
dyn_cast<ConstantInt>(Call->getArgOperand(3)))
return MemoryLocation(
Arg, LocationSize::upperBound(LenCI->getZExtValue()), AATags);
return MemoryLocation::getAfter(Arg, AATags);
default:
break;
};
}
// FIXME: Handle memset_pattern4 and memset_pattern8 also.
return MemoryLocation::getBeforeOrAfter(Call->getArgOperand(ArgIdx), AATags);
}
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