[llvm] r351621 - [CodeExtractor] Emit lifetime markers around reloads of outputs
Vedant Kumar via llvm-commits
llvm-commits at lists.llvm.org
Fri Jan 18 18:37:59 PST 2019
Author: vedantk
Date: Fri Jan 18 18:37:59 2019
New Revision: 351621
URL: http://llvm.org/viewvc/llvm-project?rev=351621&view=rev
Log:
[CodeExtractor] Emit lifetime markers around reloads of outputs
CodeExtractor permits extracting a region of blocks from a function even
when values defined within the region are used outside of it.
This is typically done by creating an alloca in the original function
and reloading the alloca after a call to the extracted function.
Wrap the reload in lifetime start/end markers to promote stack coloring.
Suggested by Sergei Kachkov!
Differential Revision: https://reviews.llvm.org/D56045
Modified:
llvm/trunk/lib/Transforms/Utils/CodeExtractor.cpp
llvm/trunk/test/Transforms/CodeExtractor/PartialInlineDebug.ll
llvm/trunk/test/Transforms/CodeExtractor/PartialInlineInvokeProducesOutVal.ll
llvm/trunk/test/Transforms/CodeExtractor/PartialInlineVarArgsDebug.ll
llvm/trunk/test/Transforms/HotColdSplit/duplicate-phi-preds-crash.ll
llvm/trunk/test/Transforms/HotColdSplit/lifetime-markers-on-inputs.ll
llvm/trunk/test/Transforms/HotColdSplit/split-phis-in-exit-blocks.ll
Modified: llvm/trunk/lib/Transforms/Utils/CodeExtractor.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Utils/CodeExtractor.cpp?rev=351621&r1=351620&r2=351621&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Utils/CodeExtractor.cpp (original)
+++ llvm/trunk/lib/Transforms/Utils/CodeExtractor.cpp Fri Jan 18 18:37:59 2019
@@ -880,6 +880,71 @@ Function *CodeExtractor::constructFuncti
return newFunction;
}
+/// Scan the extraction region for lifetime markers which reference inputs.
+/// Erase these markers. Return the inputs which were referenced.
+///
+/// The extraction region is defined by a set of blocks (\p Blocks), and a set
+/// of allocas which will be moved from the caller function into the extracted
+/// function (\p SunkAllocas).
+static SetVector<Value *>
+eraseLifetimeMarkersOnInputs(const SetVector<BasicBlock *> &Blocks,
+ const SetVector<Value *> &SunkAllocas) {
+ SetVector<Value *> InputObjectsWithLifetime;
+ for (BasicBlock *BB : Blocks) {
+ for (auto It = BB->begin(), End = BB->end(); It != End;) {
+ auto *II = dyn_cast<IntrinsicInst>(&*It);
+ ++It;
+ if (!II || !II->isLifetimeStartOrEnd())
+ continue;
+
+ // Get the memory operand of the lifetime marker. If the underlying
+ // object is a sunk alloca, or is otherwise defined in the extraction
+ // region, the lifetime marker must not be erased.
+ Value *Mem = II->getOperand(1)->stripInBoundsOffsets();
+ if (SunkAllocas.count(Mem) || definedInRegion(Blocks, Mem))
+ continue;
+
+ InputObjectsWithLifetime.insert(Mem);
+ II->eraseFromParent();
+ }
+ }
+ return InputObjectsWithLifetime;
+}
+
+/// Insert lifetime start/end markers surrounding the call to the new function
+/// for objects defined in the caller.
+static void insertLifetimeMarkersSurroundingCall(Module *M,
+ ArrayRef<Value *> Objects,
+ CallInst *TheCall) {
+ if (Objects.empty())
+ return;
+
+ LLVMContext &Ctx = M->getContext();
+ auto Int8PtrTy = Type::getInt8PtrTy(Ctx);
+ auto NegativeOne = ConstantInt::getSigned(Type::getInt64Ty(Ctx), -1);
+ auto StartFn = llvm::Intrinsic::getDeclaration(
+ M, llvm::Intrinsic::lifetime_start, Int8PtrTy);
+ auto EndFn = llvm::Intrinsic::getDeclaration(M, llvm::Intrinsic::lifetime_end,
+ Int8PtrTy);
+ Instruction *Term = TheCall->getParent()->getTerminator();
+ for (Value *Mem : Objects) {
+ assert((!isa<Instruction>(Mem) ||
+ cast<Instruction>(Mem)->getFunction() == TheCall->getFunction()) &&
+ "Input memory not defined in original function");
+ Value *MemAsI8Ptr = nullptr;
+ if (Mem->getType() == Int8PtrTy)
+ MemAsI8Ptr = Mem;
+ else
+ MemAsI8Ptr =
+ CastInst::CreatePointerCast(Mem, Int8PtrTy, "lt.cast", TheCall);
+
+ auto StartMarker = CallInst::Create(StartFn, {NegativeOne, MemAsI8Ptr});
+ StartMarker->insertBefore(TheCall);
+ auto EndMarker = CallInst::Create(EndFn, {NegativeOne, MemAsI8Ptr});
+ EndMarker->insertBefore(Term);
+ }
+}
+
/// emitCallAndSwitchStatement - This method sets up the caller side by adding
/// the call instruction, splitting any PHI nodes in the header block as
/// necessary.
@@ -1119,6 +1184,10 @@ CallInst *CodeExtractor::emitCallAndSwit
break;
}
+ // Insert lifetime markers around the reloads of any output values. The
+ // allocas output values are stored in are only in-use in the codeRepl block.
+ insertLifetimeMarkersSurroundingCall(M, ReloadOutputs, call);
+
return call;
}
@@ -1181,71 +1250,6 @@ void CodeExtractor::calculateNewCallTerm
MDBuilder(TI->getContext()).createBranchWeights(BranchWeights));
}
-/// Scan the extraction region for lifetime markers which reference inputs.
-/// Erase these markers. Return the inputs which were referenced.
-///
-/// The extraction region is defined by a set of blocks (\p Blocks), and a set
-/// of allocas which will be moved from the caller function into the extracted
-/// function (\p SunkAllocas).
-static SetVector<Value *>
-eraseLifetimeMarkersOnInputs(const SetVector<BasicBlock *> &Blocks,
- const SetVector<Value *> &SunkAllocas) {
- SetVector<Value *> InputObjectsWithLifetime;
- for (BasicBlock *BB : Blocks) {
- for (auto It = BB->begin(), End = BB->end(); It != End;) {
- auto *II = dyn_cast<IntrinsicInst>(&*It);
- ++It;
- if (!II || !II->isLifetimeStartOrEnd())
- continue;
-
- // Get the memory operand of the lifetime marker. If the underlying
- // object is a sunk alloca, or is otherwise defined in the extraction
- // region, the lifetime marker must not be erased.
- Value *Mem = II->getOperand(1)->stripInBoundsOffsets();
- if (SunkAllocas.count(Mem) || definedInRegion(Blocks, Mem))
- continue;
-
- InputObjectsWithLifetime.insert(Mem);
- II->eraseFromParent();
- }
- }
- return InputObjectsWithLifetime;
-}
-
-/// Insert lifetime start/end markers surrounding the call to the new function
-/// for objects defined in the caller.
-static void insertLifetimeMarkersSurroundingCall(
- Module *M, const SetVector<Value *> &InputObjectsWithLifetime,
- CallInst *TheCall) {
- if (InputObjectsWithLifetime.empty())
- return;
-
- LLVMContext &Ctx = M->getContext();
- auto Int8PtrTy = Type::getInt8PtrTy(Ctx);
- auto NegativeOne = ConstantInt::getSigned(Type::getInt64Ty(Ctx), -1);
- auto LifetimeStartFn = llvm::Intrinsic::getDeclaration(
- M, llvm::Intrinsic::lifetime_start, Int8PtrTy);
- auto LifetimeEndFn = llvm::Intrinsic::getDeclaration(
- M, llvm::Intrinsic::lifetime_end, Int8PtrTy);
- for (Value *Mem : InputObjectsWithLifetime) {
- assert((!isa<Instruction>(Mem) ||
- cast<Instruction>(Mem)->getFunction() == TheCall->getFunction()) &&
- "Input memory not defined in original function");
- Value *MemAsI8Ptr = nullptr;
- if (Mem->getType() == Int8PtrTy)
- MemAsI8Ptr = Mem;
- else
- MemAsI8Ptr =
- CastInst::CreatePointerCast(Mem, Int8PtrTy, "lt.cast", TheCall);
-
- auto StartMarker =
- CallInst::Create(LifetimeStartFn, {NegativeOne, MemAsI8Ptr});
- StartMarker->insertBefore(TheCall);
- auto EndMarker = CallInst::Create(LifetimeEndFn, {NegativeOne, MemAsI8Ptr});
- EndMarker->insertAfter(TheCall);
- }
-}
-
Function *CodeExtractor::extractCodeRegion() {
if (!isEligible())
return nullptr;
@@ -1389,7 +1393,8 @@ Function *CodeExtractor::extractCodeRegi
// Replicate the effects of any lifetime start/end markers which referenced
// input objects in the extraction region by placing markers around the call.
insertLifetimeMarkersSurroundingCall(oldFunction->getParent(),
- InputObjectsWithLifetime, TheCall);
+ InputObjectsWithLifetime.getArrayRef(),
+ TheCall);
// Propagate personality info to the new function if there is one.
if (oldFunction->hasPersonalityFn())
Modified: llvm/trunk/test/Transforms/CodeExtractor/PartialInlineDebug.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/CodeExtractor/PartialInlineDebug.ll?rev=351621&r1=351620&r2=351621&view=diff
==============================================================================
--- llvm/trunk/test/Transforms/CodeExtractor/PartialInlineDebug.ll (original)
+++ llvm/trunk/test/Transforms/CodeExtractor/PartialInlineDebug.ll Fri Jan 18 18:37:59 2019
@@ -23,7 +23,8 @@ if.end:
; CHECK-LABEL: @caller
; CHECK: codeRepl.i:
-; CHECK-NEXT: call void @callee.2.if.then(i32 %v, i32* %mul.loc.i), !dbg ![[DBG2:[0-9]+]]
+; CHECK-NOT: br label
+; CHECK: call void @callee.2.if.then(i32 %v, i32* %mul.loc.i), !dbg ![[DBG2:[0-9]+]]
define i32 @caller(i32 %v) !dbg !8 {
entry:
%call = call i32 @callee(i32 %v), !dbg !14
@@ -53,7 +54,8 @@ if.end:
; CHECK-LABEL: @caller2
; CHECK: codeRepl.i:
-; CHECK-NEXT: call void @callee2.1.if.then(i32 %v, i32* %sub.loc.i), !dbg ![[DBG4:[0-9]+]]
+; CHECK-NOT: br label
+; CHECK: call void @callee2.1.if.then(i32 %v, i32* %sub.loc.i), !dbg ![[DBG4:[0-9]+]]
define i32 @caller2(i32 %v) !dbg !21 {
entry:
%call = call i32 @callee2(i32 %v), !dbg !22
Modified: llvm/trunk/test/Transforms/CodeExtractor/PartialInlineInvokeProducesOutVal.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/CodeExtractor/PartialInlineInvokeProducesOutVal.ll?rev=351621&r1=351620&r2=351621&view=diff
==============================================================================
--- llvm/trunk/test/Transforms/CodeExtractor/PartialInlineInvokeProducesOutVal.ll (original)
+++ llvm/trunk/test/Transforms/CodeExtractor/PartialInlineInvokeProducesOutVal.ll Fri Jan 18 18:37:59 2019
@@ -26,7 +26,11 @@ bb5:
; CHECK-LABEL: bb:
; CHECK-NEXT: [[CALL26LOC:%.*]] = alloca i8*
; CHECK-LABEL: codeRepl.i:
+; CHECK-NEXT: %lt.cast.i = bitcast i8** [[CALL26LOC]] to i8*
+; CHECK-NEXT: call void @llvm.lifetime.start.p0i8(i64 -1, i8* %lt.cast.i)
; CHECK-NEXT: call void @bar.1.bb1(i8** [[CALL26LOC]])
+; CHECK-NEXT: %call26.reload.i = load i8*, i8** [[CALL26LOC]]
+; CHECK-NEXT: call void @llvm.lifetime.end.p0i8(i64 -1, i8* %lt.cast.i)
define i8* @dummy_caller(i32 %arg) {
bb:
%tmp = tail call i8* @bar(i32 %arg)
Modified: llvm/trunk/test/Transforms/CodeExtractor/PartialInlineVarArgsDebug.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/CodeExtractor/PartialInlineVarArgsDebug.ll?rev=351621&r1=351620&r2=351621&view=diff
==============================================================================
--- llvm/trunk/test/Transforms/CodeExtractor/PartialInlineVarArgsDebug.ll (original)
+++ llvm/trunk/test/Transforms/CodeExtractor/PartialInlineVarArgsDebug.ll Fri Jan 18 18:37:59 2019
@@ -19,7 +19,8 @@ if.end:
; CHECK-LABEL: @caller
; CHECK: codeRepl.i:
-; CHECK-NEXT: call void (i32, i32*, ...) @callee.1.if.then(i32 %v, i32* %mul.loc.i, i32 99), !dbg ![[DBG2:[0-9]+]]
+; CHECK-NOT: br label
+; CHECK: call void (i32, i32*, ...) @callee.1.if.then(i32 %v, i32* %mul.loc.i, i32 99), !dbg ![[DBG2:[0-9]+]]
define i32 @caller(i32 %v) !dbg !8 {
entry:
%call = call i32 (i32, ...) @callee(i32 %v, i32 99), !dbg !14
Modified: llvm/trunk/test/Transforms/HotColdSplit/duplicate-phi-preds-crash.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/HotColdSplit/duplicate-phi-preds-crash.ll?rev=351621&r1=351620&r2=351621&view=diff
==============================================================================
--- llvm/trunk/test/Transforms/HotColdSplit/duplicate-phi-preds-crash.ll (original)
+++ llvm/trunk/test/Transforms/HotColdSplit/duplicate-phi-preds-crash.ll Fri Jan 18 18:37:59 2019
@@ -15,7 +15,7 @@ declare void @sink() cold
; CHECK: call {{.*}}@sideeffect(
; CHECK: call {{.*}}@realloc(
; CHECK-LABEL: codeRepl:
-; CHECK-NEXT: call {{.*}}@realloc2.cold.1(i64 %size, i8* %ptr, i8** %retval.0.ce.loc)
+; CHECK: call {{.*}}@realloc2.cold.1(i64 %size, i8* %ptr, i8** %retval.0.ce.loc)
; CHECK-LABEL: cleanup:
; CHECK-NEXT: phi i8* [ null, %if.then ], [ %call, %if.end ], [ %retval.0.ce.reload, %codeRepl ]
define i8* @realloc2(i8* %ptr, i64 %size) {
Modified: llvm/trunk/test/Transforms/HotColdSplit/lifetime-markers-on-inputs.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/HotColdSplit/lifetime-markers-on-inputs.ll?rev=351621&r1=351620&r2=351621&view=diff
==============================================================================
--- llvm/trunk/test/Transforms/HotColdSplit/lifetime-markers-on-inputs.ll (original)
+++ llvm/trunk/test/Transforms/HotColdSplit/lifetime-markers-on-inputs.ll Fri Jan 18 18:37:59 2019
@@ -30,13 +30,13 @@ normalPath:
; CHECK-LABEL: codeRepl:
; CHECK: [[local1_cast:%.*]] = bitcast i256* %local1 to i8*
-; CHECK: call void @llvm.lifetime.start.p0i8(i64 -1, i8* [[local1_cast]])
-; CHECK: [[local2_cast:%.*]] = bitcast i256* %local2 to i8*
-; CHECK: call void @llvm.lifetime.start.p0i8(i64 -1, i8* [[local2_cast]])
-; CHECK: call i1 @foo.cold.1(i8* %local1_cast, i8* %local2_cast)
-; CHECK: call void @llvm.lifetime.end.p0i8(i64 -1, i8* [[local2_cast]])
-; CHECK: call void @llvm.lifetime.end.p0i8(i64 -1, i8* [[local1_cast]])
-; CHECK: br i1
+; CHECK-NEXT: call void @llvm.lifetime.start.p0i8(i64 -1, i8* [[local1_cast]])
+; CHECK-NEXT: [[local2_cast:%.*]] = bitcast i256* %local2 to i8*
+; CHECK-NEXT: call void @llvm.lifetime.start.p0i8(i64 -1, i8* [[local2_cast]])
+; CHECK-NEXT: call i1 @foo.cold.1(i8* %local1_cast, i8* %local2_cast)
+; CHECK-NEXT: call void @llvm.lifetime.end.p0i8(i64 -1, i8* [[local1_cast]])
+; CHECK-NEXT: call void @llvm.lifetime.end.p0i8(i64 -1, i8* [[local2_cast]])
+; CHECK-NEXT: br i1
outlinedPath:
; These two uses of stack slots are overlapping. This should prevent
Modified: llvm/trunk/test/Transforms/HotColdSplit/split-phis-in-exit-blocks.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/HotColdSplit/split-phis-in-exit-blocks.ll?rev=351621&r1=351620&r2=351621&view=diff
==============================================================================
--- llvm/trunk/test/Transforms/HotColdSplit/split-phis-in-exit-blocks.ll (original)
+++ llvm/trunk/test/Transforms/HotColdSplit/split-phis-in-exit-blocks.ll Fri Jan 18 18:37:59 2019
@@ -12,8 +12,11 @@ target triple = "x86_64-apple-macosx10.1
; CHECK-NEXT: ]
;
; CHECK: codeRepl:
+; CHECK-NEXT: bitcast
+; CHECK-NEXT: lifetime.start
; CHECK-NEXT: call void @pluto.cold.1(i1* %tmp8.ce.loc)
; CHECK-NEXT: %tmp8.ce.reload = load i1, i1* %tmp8.ce.loc
+; CHECK-NEXT: lifetime.end
; CHECK-NEXT: br label %bb7
;
; CHECK: bb7:
More information about the llvm-commits
mailing list