From 203f91e311f860a8d621ad2dfb1da22b6bc03fb9 Mon Sep 17 00:00:00 2001 From: Justin Bogner Date: Fri, 9 Jan 2015 01:46:40 +0000 Subject: [PATCH] InstrProf: Don't emit counter increments in dead code We were previously emitting counter increments even if we didn't have an insertion point, which would result in a CallInst with no parent. This leads to a crash, as in pr22166, if we try to do GlobalDCE. llvm-svn: 225495 --- clang/lib/CodeGen/CodeGenPGO.cpp | 2 ++ clang/test/Profile/c-unreachable-after-switch.c | 15 +++++++++++++++ 2 files changed, 17 insertions(+) create mode 100644 clang/test/Profile/c-unreachable-after-switch.c diff --git a/clang/lib/CodeGen/CodeGenPGO.cpp b/clang/lib/CodeGen/CodeGenPGO.cpp index 71bd1ca351df..24b035d67598 100644 --- a/clang/lib/CodeGen/CodeGenPGO.cpp +++ b/clang/lib/CodeGen/CodeGenPGO.cpp @@ -788,6 +788,8 @@ CodeGenPGO::applyFunctionAttributes(llvm::IndexedInstrProfReader *PGOReader, void CodeGenPGO::emitCounterIncrement(CGBuilderTy &Builder, unsigned Counter) { if (!CGM.getCodeGenOpts().ProfileInstrGenerate || !RegionCounterMap) return; + if (!Builder.GetInsertPoint()) + return; auto *I8PtrTy = llvm::Type::getInt8PtrTy(CGM.getLLVMContext()); Builder.CreateCall4(CGM.getIntrinsic(llvm::Intrinsic::instrprof_increment), llvm::ConstantExpr::getBitCast(FuncNameVar, I8PtrTy), diff --git a/clang/test/Profile/c-unreachable-after-switch.c b/clang/test/Profile/c-unreachable-after-switch.c new file mode 100644 index 000000000000..077043751058 --- /dev/null +++ b/clang/test/Profile/c-unreachable-after-switch.c @@ -0,0 +1,15 @@ +// RUN: %clang_cc1 -O3 -triple x86_64-apple-macosx10.10 -main-file-name c-unreachable-after-switch.c %s -o - -emit-llvm -fprofile-instr-generate | FileCheck %s + +// CHECK: @[[C:__llvm_profile_counters_foo]] = hidden global [3 x i64] zeroinitializer + +// CHECK-LABEL: @foo() +// CHECK: store {{.*}} @[[C]], i64 0, i64 0 +void foo() { + // CHECK: store {{.*}} @[[C]], i64 0, i64 2 + switch (0) { + default: + return; + } + // We shouldn't emit the unreachable counter. This used to crash in GlobalDCE. + // CHECK-NOT: store {{.*}} @[[SWC]], i64 0, i64 1} +}