diff options
| -rw-r--r-- | llvm/lib/Transforms/Utils/Local.cpp | 2 | ||||
| -rw-r--r-- | llvm/test/Transforms/SimplifyCFG/noreturn-call.ll | 22 |
2 files changed, 21 insertions, 3 deletions
diff --git a/llvm/lib/Transforms/Utils/Local.cpp b/llvm/lib/Transforms/Utils/Local.cpp index 429ae85596f..7024c663e30 100644 --- a/llvm/lib/Transforms/Utils/Local.cpp +++ b/llvm/lib/Transforms/Utils/Local.cpp @@ -2054,7 +2054,7 @@ static bool markAliveBlocks(Function &F, Changed = true; break; } - if (CI->doesNotReturn()) { + if (CI->doesNotReturn() && !CI->isMustTailCall()) { // If we found a call to a no-return function, insert an unreachable // instruction after it. Make sure there isn't *already* one there // though. diff --git a/llvm/test/Transforms/SimplifyCFG/noreturn-call.ll b/llvm/test/Transforms/SimplifyCFG/noreturn-call.ll index b4547782837..88d4f85713b 100644 --- a/llvm/test/Transforms/SimplifyCFG/noreturn-call.ll +++ b/llvm/test/Transforms/SimplifyCFG/noreturn-call.ll @@ -1,11 +1,29 @@ -; RUN: opt < %s -simplifycfg -S | grep unreachable +; RUN: opt < %s -simplifycfg -S | FileCheck %s ; PR1796 declare void @Finisher(i32) noreturn -define void @YYY(i32) { +; Make sure we optimize a sequence of two calls (second unreachable); +define void @double_call(i32) { +; CHECK-LABEL: @double_call( +; CHECK-NEXT: tail call void @Finisher(i32 %0) #0 +; CHECK-NEXT: unreachable +; tail call void @Finisher(i32 %0) noreturn tail call void @Finisher(i32 %0) noreturn ret void } +; Make sure we DON'T try to optimize a musttail call (the IR invariant +; is that it must be followed by [optional bitcast then] ret). +define void @must_tail(i32) { +; CHECK-LABEL: @must_tail( +; CHECK-NEXT: musttail call void @Finisher(i32 %0) #0 +; CHECK-NEXT: ret void +; + musttail call void @Finisher(i32 %0) #0 + ret void +} + +; CHECK: attributes #0 = { noreturn } +attributes #0 = { noreturn } |
