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[DirectX] Lower llvm.lifetime.* intrinsics to stores when DXIL version is lower than 1.6 #147432

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69 changes: 55 additions & 14 deletions llvm/lib/Target/DirectX/DXILOpLowering.cpp
Original file line number Diff line number Diff line change
Expand Up @@ -39,11 +39,13 @@ class OpLowerer {
DXILOpBuilder OpBuilder;
DXILResourceMap &DRM;
DXILResourceTypeMap &DRTM;
const ModuleMetadataInfo &MMDI;
SmallVector<CallInst *> CleanupCasts;

public:
OpLowerer(Module &M, DXILResourceMap &DRM, DXILResourceTypeMap &DRTM)
: M(M), OpBuilder(M), DRM(DRM), DRTM(DRTM) {}
OpLowerer(Module &M, DXILResourceMap &DRM, DXILResourceTypeMap &DRTM,
const ModuleMetadataInfo &MMDI)
: M(M), OpBuilder(M), DRM(DRM), DRTM(DRTM), MMDI(MMDI) {}

/// Replace every call to \c F using \c ReplaceCall, and then erase \c F. If
/// there is an error replacing a call, we emit a diagnostic and return true.
Expand Down Expand Up @@ -316,8 +318,7 @@ class OpLowerer {
/// model and taking into account binding information from
/// DXILResourceAnalysis.
bool lowerHandleFromBinding(Function &F) {
const Triple &TT = M.getTargetTriple();
if (TT.getDXILVersion() < VersionTuple(1, 6))
if (MMDI.DXILVersion < VersionTuple(1, 6))
return lowerToCreateHandle(F);
return lowerToBindAndAnnotateHandle(F);
}
Expand Down Expand Up @@ -486,8 +487,6 @@ class OpLowerer {
}

[[nodiscard]] bool lowerRawBufferLoad(Function &F) {
const Triple &TT = M.getTargetTriple();
VersionTuple DXILVersion = TT.getDXILVersion();
const DataLayout &DL = F.getDataLayout();
IRBuilder<> &IRB = OpBuilder.getIRB();
Type *Int8Ty = IRB.getInt8Ty();
Expand All @@ -511,7 +510,7 @@ class OpLowerer {
ConstantInt::get(Int32Ty, DL.getPrefTypeAlign(ScalarTy).value());

Expected<CallInst *> OpCall =
DXILVersion >= VersionTuple(1, 2)
MMDI.DXILVersion >= VersionTuple(1, 2)
? OpBuilder.tryCreateOp(OpCode::RawBufferLoad,
{Handle, Index0, Index1, Mask, Align},
CI->getName(), NewRetTy)
Expand Down Expand Up @@ -586,8 +585,6 @@ class OpLowerer {
}

[[nodiscard]] bool lowerBufferStore(Function &F, bool IsRaw) {
const Triple &TT = M.getTargetTriple();
VersionTuple DXILVersion = TT.getDXILVersion();
const DataLayout &DL = F.getDataLayout();
IRBuilder<> &IRB = OpBuilder.getIRB();
Type *Int8Ty = IRB.getInt8Ty();
Expand Down Expand Up @@ -654,7 +651,7 @@ class OpLowerer {
SmallVector<Value *, 9> Args{
Handle, Index0, Index1, DataElements[0],
DataElements[1], DataElements[2], DataElements[3], Mask};
if (IsRaw && DXILVersion >= VersionTuple(1, 2)) {
if (IsRaw && MMDI.DXILVersion >= VersionTuple(1, 2)) {
Op = OpCode::RawBufferStore;
// RawBufferStore requires the alignment
Args.push_back(
Expand Down Expand Up @@ -745,6 +742,37 @@ class OpLowerer {
});
}

[[nodiscard]] bool lowerLifetimeIntrinsic(Function &F) {
IRBuilder<> &IRB = OpBuilder.getIRB();
return replaceFunction(F, [&](CallInst *CI) -> Error {
IRB.SetInsertPoint(CI);
Value *Ptr = CI->getArgOperand(1);
assert(Ptr->getType()->isPointerTy() &&
"Expected operand of lifetime intrinsic to be a pointer");

auto ZeroOrUndef = [&](Type *Ty) {
return MMDI.ValidatorVersion < VersionTuple(1, 6)
? Constant::getNullValue(Ty)
: UndefValue::get(Ty);
};

Value *Val = nullptr;
if (auto *GV = dyn_cast<GlobalVariable>(Ptr)) {
if (GV->hasInitializer() || GV->isExternallyInitialized())
return Error::success();
Val = ZeroOrUndef(GV->getValueType());
} else if (auto *AI = dyn_cast<AllocaInst>(Ptr))
Val = ZeroOrUndef(AI->getAllocatedType());

assert(Val && "Expected operand of lifetime intrinsic to be a global "
"variable or alloca instruction");
IRB.CreateStore(Val, Ptr, false);

CI->eraseFromParent();
return Error::success();
});
}

[[nodiscard]] bool lowerIsFPClass(Function &F) {
IRBuilder<> &IRB = OpBuilder.getIRB();
Type *RetTy = IRB.getInt1Ty();
Expand Down Expand Up @@ -803,8 +831,6 @@ class OpLowerer {
case Intrinsic::dx_resource_casthandle:
// NOTE: llvm.dbg.value is supported as is in DXIL.
case Intrinsic::dbg_value:
case Intrinsic::lifetime_start:
case Intrinsic::lifetime_end:
case Intrinsic::not_intrinsic:
if (F.use_empty())
F.eraseFromParent();
Expand Down Expand Up @@ -855,6 +881,17 @@ class OpLowerer {
case Intrinsic::ctpop:
HasErrors |= lowerCtpopToCountBits(F);
break;
case Intrinsic::lifetime_start:
case Intrinsic::lifetime_end:
if (F.use_empty())
F.eraseFromParent();
else {
if (MMDI.DXILVersion < VersionTuple(1, 6))
HasErrors |= lowerLifetimeIntrinsic(F);
else
continue;
}
break;
case Intrinsic::is_fpclass:
HasErrors |= lowerIsFPClass(F);
break;
Expand All @@ -872,8 +909,9 @@ class OpLowerer {
PreservedAnalyses DXILOpLowering::run(Module &M, ModuleAnalysisManager &MAM) {
DXILResourceMap &DRM = MAM.getResult<DXILResourceAnalysis>(M);
DXILResourceTypeMap &DRTM = MAM.getResult<DXILResourceTypeAnalysis>(M);
const ModuleMetadataInfo MMDI = MAM.getResult<DXILMetadataAnalysis>(M);

bool MadeChanges = OpLowerer(M, DRM, DRTM).lowerIntrinsics();
const bool MadeChanges = OpLowerer(M, DRM, DRTM, MMDI).lowerIntrinsics();
if (!MadeChanges)
return PreservedAnalyses::all();
PreservedAnalyses PA;
Expand All @@ -891,8 +929,10 @@ class DXILOpLoweringLegacy : public ModulePass {
getAnalysis<DXILResourceWrapperPass>().getResourceMap();
DXILResourceTypeMap &DRTM =
getAnalysis<DXILResourceTypeWrapperPass>().getResourceTypeMap();
const ModuleMetadataInfo MMDI =
getAnalysis<DXILMetadataAnalysisWrapperPass>().getModuleMetadata();

return OpLowerer(M, DRM, DRTM).lowerIntrinsics();
return OpLowerer(M, DRM, DRTM, MMDI).lowerIntrinsics();
}
StringRef getPassName() const override { return "DXIL Op Lowering"; }
DXILOpLoweringLegacy() : ModulePass(ID) {}
Expand All @@ -901,6 +941,7 @@ class DXILOpLoweringLegacy : public ModulePass {
void getAnalysisUsage(llvm::AnalysisUsage &AU) const override {
AU.addRequired<DXILResourceTypeWrapperPass>();
AU.addRequired<DXILResourceWrapperPass>();
AU.addRequired<DXILMetadataAnalysisWrapperPass>();
AU.addPreserved<DXILResourceWrapperPass>();
AU.addPreserved<DXILMetadataAnalysisWrapperPass>();
AU.addPreserved<ShaderFlagsAnalysisWrapper>();
Expand Down
Original file line number Diff line number Diff line change
Expand Up @@ -3,9 +3,9 @@
; CHECK-LABEL: define void @test_legal_lifetime() {
; CHECK-NEXT: [[ACCUM_I_FLAT:%.*]] = alloca [1 x i32], align 4
; CHECK-NEXT: [[GEP:%.*]] = getelementptr i32, ptr [[ACCUM_I_FLAT]], i32 0
; CHECK-NEXT: call void @llvm.lifetime.start.p0(i64 4, ptr nonnull [[ACCUM_I_FLAT]])
; CHECK-NEXT: store [1 x i32] zeroinitializer, ptr [[ACCUM_I_FLAT]], align 4
; CHECK-NEXT: store i32 0, ptr [[GEP]], align 4
; CHECK-NEXT: call void @llvm.lifetime.end.p0(i64 4, ptr nonnull [[ACCUM_I_FLAT]])
; CHECK-NEXT: store [1 x i32] zeroinitializer, ptr [[ACCUM_I_FLAT]], align 4
; CHECK-NEXT: ret void
;
define void @test_legal_lifetime() {
Expand All @@ -16,3 +16,7 @@ define void @test_legal_lifetime() {
call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %accum.i.flat)
ret void
}

; Set the validator version to 1.5
!dx.valver = !{!0}
!0 = !{i32 1, i32 5}
31 changes: 31 additions & 0 deletions llvm/test/CodeGen/DirectX/legalize-lifetimes-valver-1.6.ll
Original file line number Diff line number Diff line change
@@ -0,0 +1,31 @@
; RUN: opt -S -passes='dxil-op-lower' -mtriple=dxil-pc-shadermodel6.3-library %s | FileCheck %s --check-prefixes=CHECK,CHECK-SM63
; RUN: opt -S -passes='dxil-op-lower' -mtriple=dxil-pc-shadermodel6.6-library %s | FileCheck %s --check-prefixes=CHECK,CHECK-SM66

; CHECK-LABEL: define void @test_legal_lifetime() {
;
; CHECK-SM63-NEXT: [[ACCUM_I_FLAT:%.*]] = alloca [1 x i32], align 4
; CHECK-SM63-NEXT: [[GEP:%.*]] = getelementptr i32, ptr [[ACCUM_I_FLAT]], i32 0
; CHECK-SM63-NEXT: store [1 x i32] undef, ptr [[ACCUM_I_FLAT]], align 4
; CHECK-SM63-NEXT: store i32 0, ptr [[GEP]], align 4
; CHECK-SM63-NEXT: store [1 x i32] undef, ptr [[ACCUM_I_FLAT]], align 4
;
; CHECK-SM66-NEXT: [[ACCUM_I_FLAT:%.*]] = alloca [1 x i32], align 4
; CHECK-SM66-NEXT: [[GEP:%.*]] = getelementptr i32, ptr [[ACCUM_I_FLAT]], i32 0
; CHECK-SM66-NEXT: call void @llvm.lifetime.start.p0(i64 4, ptr nonnull [[ACCUM_I_FLAT]])
; CHECK-SM66-NEXT: store i32 0, ptr [[GEP]], align 4
; CHECK-SM66-NEXT: call void @llvm.lifetime.end.p0(i64 4, ptr nonnull [[ACCUM_I_FLAT]])
;
; CHECK-NEXT: ret void
;
define void @test_legal_lifetime() {
%accum.i.flat = alloca [1 x i32], align 4
%gep = getelementptr i32, ptr %accum.i.flat, i32 0
call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %accum.i.flat)
store i32 0, ptr %gep, align 4
call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %accum.i.flat)
ret void
}

; Set the validator version to 1.6
!dx.valver = !{!0}
!0 = !{i32 1, i32 6}
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