diff options
| -rw-r--r-- | llvm/include/llvm/Transforms/Utils/Local.h | 6 | ||||
| -rw-r--r-- | llvm/lib/Transforms/IPO/Attributor.cpp | 26 | ||||
| -rw-r--r-- | llvm/lib/Transforms/Utils/Local.cpp | 18 | ||||
| -rw-r--r-- | llvm/test/Transforms/FunctionAttrs/liveness.ll | 7 |
4 files changed, 44 insertions, 13 deletions
diff --git a/llvm/include/llvm/Transforms/Utils/Local.h b/llvm/include/llvm/Transforms/Utils/Local.h index ee8df756d72..5c5e0aef34c 100644 --- a/llvm/include/llvm/Transforms/Utils/Local.h +++ b/llvm/include/llvm/Transforms/Utils/Local.h @@ -271,6 +271,12 @@ inline unsigned getKnownAlignment(Value *V, const DataLayout &DL, return getOrEnforceKnownAlignment(V, 0, DL, CxtI, AC, DT); } +/// Create a call that matches the invoke \p II in terms of arguments, +/// attributes, debug information, etc. The call is not placed in a block and it +/// will not have a name. The invoke instruction is not removed, nor are the +/// uses replaced by the new call. +CallInst *createCallMatchingInvoke(InvokeInst *II); + /// This function converts the specified invoek into a normall call. void changeToCall(InvokeInst *II, DomTreeUpdater *DTU = nullptr); diff --git a/llvm/lib/Transforms/IPO/Attributor.cpp b/llvm/lib/Transforms/IPO/Attributor.cpp index 1ae8ac77de0..3ecad8b03eb 100644 --- a/llvm/lib/Transforms/IPO/Attributor.cpp +++ b/llvm/lib/Transforms/IPO/Attributor.cpp @@ -1577,6 +1577,11 @@ struct AAIsDeadFunction : AAIsDead, BooleanState { Instruction *SplitPos = I->getNextNode(); if (auto *II = dyn_cast<InvokeInst>(I)) { + // If we keep the invoke the split position is at the beginning of the + // normal desitination block (it invokes a noreturn function after all). + BasicBlock *NormalDestBB = II->getNormalDest(); + SplitPos = &NormalDestBB->front(); + /// Invoke is replaced with a call and unreachable is placed after it if /// the callee is nounwind and noreturn. Otherwise, we keep the invoke /// and only place an unreachable in the normal successor. @@ -1587,17 +1592,26 @@ struct AAIsDeadFunction : AAIsDead, BooleanState { (AANoUnw && AANoUnw->isAssumedNoUnwind())) { LLVM_DEBUG(dbgs() << "[AAIsDead] Replace invoke with call inst\n"); - changeToCall(II); - changeToUnreachable(BB->getTerminator(), /* UseLLVMTrap */ false); - continue; + // We do not need an invoke (II) but instead want a call followed + // by an unreachable. However, we do not remove II as other + // abstract attributes might have it cached as part of their + // results. Given that we modify the CFG anyway, we simply keep II + // around but in a new dead block. To avoid II being live through + // a different edge we have to ensure the block we place it in is + // only reached from the current block of II and then not reached + // at all when we insert the unreachable. + SplitBlockPredecessors(NormalDestBB, {BB}, ".i2c"); + CallInst *CI = createCallMatchingInvoke(II); + CI->insertBefore(II); + CI->takeName(II); + II->replaceAllUsesWith(CI); + SplitPos = CI->getNextNode(); } } } - - BB = II->getNormalDest(); - SplitPos = &BB->front(); } + BB = SplitPos->getParent(); SplitBlock(BB, SplitPos); changeToUnreachable(BB->getTerminator(), /* UseLLVMTrap */ false); HasChanged = ChangeStatus::CHANGED; diff --git a/llvm/lib/Transforms/Utils/Local.cpp b/llvm/lib/Transforms/Utils/Local.cpp index 68443c15a78..a1d1b3ec84f 100644 --- a/llvm/lib/Transforms/Utils/Local.cpp +++ b/llvm/lib/Transforms/Utils/Local.cpp @@ -1933,18 +1933,24 @@ unsigned llvm::changeToUnreachable(Instruction *I, bool UseLLVMTrap, return NumInstrsRemoved; } -/// changeToCall - Convert the specified invoke into a normal call. -void llvm::changeToCall(InvokeInst *II, DomTreeUpdater *DTU) { - SmallVector<Value*, 8> Args(II->arg_begin(), II->arg_end()); +CallInst *llvm::createCallMatchingInvoke(InvokeInst *II) { + SmallVector<Value *, 8> Args(II->arg_begin(), II->arg_end()); SmallVector<OperandBundleDef, 1> OpBundles; II->getOperandBundlesAsDefs(OpBundles); - CallInst *NewCall = CallInst::Create( - II->getFunctionType(), II->getCalledValue(), Args, OpBundles, "", II); - NewCall->takeName(II); + CallInst *NewCall = CallInst::Create(II->getFunctionType(), + II->getCalledValue(), Args, OpBundles); NewCall->setCallingConv(II->getCallingConv()); NewCall->setAttributes(II->getAttributes()); NewCall->setDebugLoc(II->getDebugLoc()); NewCall->copyMetadata(*II); + return NewCall; +} + +/// changeToCall - Convert the specified invoke into a normal call. +void llvm::changeToCall(InvokeInst *II, DomTreeUpdater *DTU) { + CallInst *NewCall = createCallMatchingInvoke(II); + NewCall->takeName(II); + NewCall->insertBefore(II); II->replaceAllUsesWith(NewCall); // Follow the call by a branch to the normal destination. diff --git a/llvm/test/Transforms/FunctionAttrs/liveness.ll b/llvm/test/Transforms/FunctionAttrs/liveness.ll index cbf5631e6eb..166b15441e4 100644 --- a/llvm/test/Transforms/FunctionAttrs/liveness.ll +++ b/llvm/test/Transforms/FunctionAttrs/liveness.ll @@ -184,9 +184,14 @@ cond.true: ; preds = %entry call void @normal_call() %call = invoke i32 @foo_noreturn_nounwind() to label %continue unwind label %cleanup - ; CHECK: call i32 @foo_noreturn_nounwind() + ; CHECK: call void @normal_call() + ; CHECK-NEXT: call i32 @foo_noreturn_nounwind() ; CHECK-NEXT: unreachable + ; We keep the invoke around as other attributes might have references to it. + ; CHECK: cond.true.split: ; No predecessors! + ; CHECK-NEXT: invoke i32 @foo_noreturn_nounwind() + cond.false: ; preds = %entry call void @normal_call() %call1 = call i32 @bar() |
