Finish adding support for lifetime intrinsics to SROA. Fixes PR10121!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@136008 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Nick Lewycky 2011-07-25 23:14:22 +00:00
parent dbc46d7dd8
commit 5a1cb644c9
2 changed files with 249 additions and 1 deletions

View File

@ -145,6 +145,9 @@ namespace {
SmallVector<AllocaInst*, 32> &NewElts);
void RewriteGEP(GetElementPtrInst *GEPI, AllocaInst *AI, uint64_t Offset,
SmallVector<AllocaInst*, 32> &NewElts);
void RewriteLifetimeIntrinsic(IntrinsicInst *II, AllocaInst *AI,
uint64_t Offset,
SmallVector<AllocaInst*, 32> &NewElts);
void RewriteMemIntrinUserOfAlloca(MemIntrinsic *MI, Instruction *Inst,
AllocaInst *AI,
SmallVector<AllocaInst*, 32> &NewElts);
@ -508,6 +511,7 @@ bool ConvertToScalarInfo::CanConvertToScalar(Value *V, uint64_t Offset) {
}
if (BitCastInst *BCI = dyn_cast<BitCastInst>(User)) {
if (!onlyUsedByLifetimeMarkers(BCI))
IsNotTrivial = true; // Can't be mem2reg'd.
if (!CanConvertToScalar(BCI, Offset))
return false;
@ -566,6 +570,14 @@ bool ConvertToScalarInfo::CanConvertToScalar(Value *V, uint64_t Offset) {
continue;
}
// If this is a lifetime intrinsic, we can handle it.
if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(User)) {
if (II->getIntrinsicID() == Intrinsic::lifetime_start ||
II->getIntrinsicID() == Intrinsic::lifetime_end) {
continue;
}
}
// Otherwise, we cannot handle this!
return false;
}
@ -709,6 +721,16 @@ void ConvertToScalarInfo::ConvertUsesToScalar(Value *Ptr, AllocaInst *NewAI,
continue;
}
if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(User)) {
if (II->getIntrinsicID() == Intrinsic::lifetime_start ||
II->getIntrinsicID() == Intrinsic::lifetime_end) {
// There's no need to preserve these, as the resulting alloca will be
// converted to a register anyways.
II->eraseFromParent();
continue;
}
}
llvm_unreachable("Unsupported operation!");
}
}
@ -1349,6 +1371,13 @@ static bool tryToMakeAllocaBePromotable(AllocaInst *AI, const TargetData *TD) {
continue;
}
if (BitCastInst *BCI = dyn_cast<BitCastInst>(U)) {
if (onlyUsedByLifetimeMarkers(BCI)) {
InstsToRewrite.insert(BCI);
continue;
}
}
return false;
}
@ -1360,6 +1389,18 @@ static bool tryToMakeAllocaBePromotable(AllocaInst *AI, const TargetData *TD) {
// If we have instructions that need to be rewritten for this to be promotable
// take care of it now.
for (unsigned i = 0, e = InstsToRewrite.size(); i != e; ++i) {
if (BitCastInst *BCI = dyn_cast<BitCastInst>(InstsToRewrite[i])) {
// This could only be a bitcast used by nothing but lifetime intrinsics.
for (BitCastInst::use_iterator I = BCI->use_begin(), E = BCI->use_end();
I != E;) {
Use &U = I.getUse();
++I;
cast<Instruction>(U.getUser())->eraseFromParent();
}
BCI->eraseFromParent();
continue;
}
if (SelectInst *SI = dyn_cast<SelectInst>(InstsToRewrite[i])) {
// Selects in InstsToRewrite only have load uses. Rewrite each as two
// loads with a new select.
@ -1692,6 +1733,10 @@ void SROA::isSafeForScalarRepl(Instruction *I, uint64_t Offset,
isSafeMemAccess(Offset, TD->getTypeAllocSize(SIType),
SIType, true, Info, SI, true /*AllowWholeAccess*/);
Info.hasALoadOrStore = true;
} else if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(User)) {
if (II->getIntrinsicID() != Intrinsic::lifetime_start &&
II->getIntrinsicID() != Intrinsic::lifetime_end)
return MarkUnsafe(Info, User);
} else if (isa<PHINode>(User) || isa<SelectInst>(User)) {
isSafePHISelectUseForScalarRepl(User, Offset, Info);
} else {
@ -1930,6 +1975,14 @@ void SROA::RewriteForScalarRepl(Instruction *I, AllocaInst *AI, uint64_t Offset,
continue;
}
if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(User)) {
if (II->getIntrinsicID() == Intrinsic::lifetime_start ||
II->getIntrinsicID() == Intrinsic::lifetime_end) {
RewriteLifetimeIntrinsic(II, AI, Offset, NewElts);
}
continue;
}
if (LoadInst *LI = dyn_cast<LoadInst>(User)) {
Type *LIType = LI->getType();
@ -2095,6 +2148,62 @@ void SROA::RewriteGEP(GetElementPtrInst *GEPI, AllocaInst *AI, uint64_t Offset,
DeadInsts.push_back(GEPI);
}
/// RewriteLifetimeIntrinsic - II is a lifetime.start/lifetime.end. Rewrite it
/// to mark the lifetime of the scalarized memory.
void SROA::RewriteLifetimeIntrinsic(IntrinsicInst *II, AllocaInst *AI,
uint64_t Offset,
SmallVector<AllocaInst*, 32> &NewElts) {
ConstantInt *OldSize = cast<ConstantInt>(II->getArgOperand(0));
// Put matching lifetime markers on everything from Offset up to
// Offset+OldSize.
Type *AIType = AI->getAllocatedType();
uint64_t NewOffset = Offset;
Type *IdxTy;
uint64_t Idx = FindElementAndOffset(AIType, NewOffset, IdxTy);
IRBuilder<> Builder(II);
uint64_t Size = OldSize->getLimitedValue();
if (NewOffset) {
// Splice the first element and index 'NewOffset' bytes in. SROA will
// split the alloca again later.
Value *V = Builder.CreateBitCast(NewElts[Idx], Builder.getInt8PtrTy());
V = Builder.CreateGEP(V, Builder.getInt64(NewOffset));
IdxTy = NewElts[Idx]->getAllocatedType();
uint64_t EltSize = TD->getTypeAllocSize(IdxTy) - NewOffset;
if (EltSize > Size) {
EltSize = Size;
Size = 0;
} else {
Size -= EltSize;
}
if (II->getIntrinsicID() == Intrinsic::lifetime_start)
Builder.CreateLifetimeStart(V, Builder.getInt64(EltSize));
else
Builder.CreateLifetimeEnd(V, Builder.getInt64(EltSize));
++Idx;
}
for (; Idx != NewElts.size() && Size; ++Idx) {
IdxTy = NewElts[Idx]->getAllocatedType();
uint64_t EltSize = TD->getTypeAllocSize(IdxTy);
if (EltSize > Size) {
EltSize = Size;
Size = 0;
} else {
Size -= EltSize;
}
if (II->getIntrinsicID() == Intrinsic::lifetime_start)
Builder.CreateLifetimeStart(NewElts[Idx],
Builder.getInt64(EltSize));
else
Builder.CreateLifetimeEnd(NewElts[Idx],
Builder.getInt64(EltSize));
}
DeadInsts.push_back(II);
}
/// RewriteMemIntrinUserOfAlloca - MI is a memcpy/memset/memmove from or to AI.
/// Rewrite it to copy or set the elements of the scalarized memory.
void SROA::RewriteMemIntrinUserOfAlloca(MemIntrinsic *MI, Instruction *Inst,

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@ -0,0 +1,139 @@
; RUN: opt -scalarrepl -S < %s | FileCheck %s
target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
target triple = "x86_64-unknown-linux-gnu"
declare void @llvm.lifetime.start(i64, i8*)
declare void @llvm.lifetime.end(i64, i8*)
%t1 = type {i32, i32, i32}
define void @test1() {
; CHECK: @test1
%A = alloca %t1
%A1 = getelementptr %t1* %A, i32 0, i32 0
%A2 = getelementptr %t1* %A, i32 0, i32 1
%A3 = getelementptr %t1* %A, i32 0, i32 2
%B = bitcast i32* %A1 to i8*
store i32 0, i32* %A1
call void @llvm.lifetime.start(i64 -1, i8* %B)
ret void
; CHECK-NEXT: ret void
}
define void @test2() {
; CHECK: @test2
%A = alloca %t1
%A1 = getelementptr %t1* %A, i32 0, i32 0
%A2 = getelementptr %t1* %A, i32 0, i32 1
%A3 = getelementptr %t1* %A, i32 0, i32 2
%B = bitcast i32* %A2 to i8*
store i32 0, i32* %A2
call void @llvm.lifetime.start(i64 -1, i8* %B)
%C = load i32* %A2
ret void
; CHECK: ret void
}
define void @test3() {
; CHECK: @test3
%A = alloca %t1
%A1 = getelementptr %t1* %A, i32 0, i32 0
%A2 = getelementptr %t1* %A, i32 0, i32 1
%A3 = getelementptr %t1* %A, i32 0, i32 2
%B = bitcast i32* %A2 to i8*
store i32 0, i32* %A2
call void @llvm.lifetime.start(i64 6, i8* %B)
%C = load i32* %A2
ret void
; CHECK-NEXT: ret void
}
define void @test4() {
; CHECK: @test4
%A = alloca %t1
%A1 = getelementptr %t1* %A, i32 0, i32 0
%A2 = getelementptr %t1* %A, i32 0, i32 1
%A3 = getelementptr %t1* %A, i32 0, i32 2
%B = bitcast i32* %A2 to i8*
store i32 0, i32* %A2
call void @llvm.lifetime.start(i64 1, i8* %B)
%C = load i32* %A2
ret void
; CHECK-NEXT: ret void
}
%t2 = type {i32, [4 x i8], i32}
define void @test5() {
; CHECK: @test5
%A = alloca %t2
; CHECK: alloca{{.*}}i8
; CHECK: alloca{{.*}}i8
; CHECK: alloca{{.*}}i8
%A21 = getelementptr %t2* %A, i32 0, i32 1, i32 0
%A22 = getelementptr %t2* %A, i32 0, i32 1, i32 1
%A23 = getelementptr %t2* %A, i32 0, i32 1, i32 2
%A24 = getelementptr %t2* %A, i32 0, i32 1, i32 3
; CHECK-NOT: store i8 1
store i8 1, i8* %A21
store i8 2, i8* %A22
store i8 3, i8* %A23
store i8 4, i8* %A24
%A1 = getelementptr %t2* %A, i32 0, i32 0
%A2 = getelementptr %t2* %A, i32 0, i32 1, i32 1
%A3 = getelementptr %t2* %A, i32 0, i32 2
store i8 0, i8* %A2
call void @llvm.lifetime.start(i64 5, i8* %A2)
; CHECK: llvm.lifetime{{.*}}i64 1
; CHECK: llvm.lifetime{{.*}}i64 1
; CHECK: llvm.lifetime{{.*}}i64 1
%C = load i8* %A2
ret void
}
%t3 = type {[4 x i16], [4 x i8]}
define void @test6() {
; CHECK: @test6
%A = alloca %t3
; CHECK: alloca i8
; CHECK: alloca i8
; CHECK: alloca i8
%A11 = getelementptr %t3* %A, i32 0, i32 0, i32 0
%A12 = getelementptr %t3* %A, i32 0, i32 0, i32 1
%A13 = getelementptr %t3* %A, i32 0, i32 0, i32 2
%A14 = getelementptr %t3* %A, i32 0, i32 0, i32 3
store i16 11, i16* %A11
store i16 12, i16* %A12
store i16 13, i16* %A13
store i16 14, i16* %A14
; CHECK-NOT: store i16 11
; CHECK-NOT: store i16 12
; CHECK-NOT: store i16 13
; CHECK-NOT: store i16 14
%A21 = getelementptr %t3* %A, i32 0, i32 1, i32 0
%A22 = getelementptr %t3* %A, i32 0, i32 1, i32 1
%A23 = getelementptr %t3* %A, i32 0, i32 1, i32 2
%A24 = getelementptr %t3* %A, i32 0, i32 1, i32 3
store i8 21, i8* %A21
store i8 22, i8* %A22
store i8 23, i8* %A23
store i8 24, i8* %A24
; CHECK: store i8 21
; CHECK: store i8 22
; CHECK: store i8 23
; CHECK-NOT: store i8 24
%B = bitcast i16* %A13 to i8*
call void @llvm.lifetime.start(i64 7, i8* %B)
; CHECK: lifetime.start{{.*}}i64 1
; CHECK: lifetime.start{{.*}}i64 1
; CHECK: lifetime.start{{.*}}i64 1
ret void
}