diff options
| author | Erich Keane <erich.keane@intel.com> | 2018-12-12 20:30:53 +0000 |
|---|---|---|
| committer | Erich Keane <erich.keane@intel.com> | 2018-12-12 20:30:53 +0000 |
| commit | 9bbaece3b730921391adad895e3d46dfd945f6d7 (patch) | |
| tree | e03b9593fb74318618fb6160a5e009befbb94030 | |
| parent | cca2337ba25bac834d797226f797279756c8b6b9 (diff) | |
Teach __builtin_unpredictable to work through implicit casts.
The __builtin_unpredictable implementation is confused by any implicit
casts, which happen in C++. This patch strips those off so that
if/switch statements now work with it in C++.
Change-Id: I73c3bf4f1775cd906703880944f4fcdc29fffb0a
| -rw-r--r-- | clang/lib/CodeGen/CodeGenFunction.cpp | 2 | ||||
| -rw-r--r-- | clang/test/CodeGen/builtin-unpredictable.c | 12 |
2 files changed, 12 insertions, 2 deletions
diff --git a/clang/lib/CodeGen/CodeGenFunction.cpp b/clang/lib/CodeGen/CodeGenFunction.cpp index 905e7501e01..3f898b19e67 100644 --- a/clang/lib/CodeGen/CodeGenFunction.cpp +++ b/clang/lib/CodeGen/CodeGenFunction.cpp @@ -1701,7 +1701,7 @@ void CodeGenFunction::EmitBranchOnBoolExpr(const Expr *Cond, // create metadata that specifies that the branch is unpredictable. // Don't bother if not optimizing because that metadata would not be used. llvm::MDNode *Unpredictable = nullptr; - auto *Call = dyn_cast<CallExpr>(Cond); + auto *Call = dyn_cast<CallExpr>(Cond->IgnoreImpCasts()); if (Call && CGM.getCodeGenOpts().OptimizationLevel != 0) { auto *FD = dyn_cast_or_null<FunctionDecl>(Call->getCalleeDecl()); if (FD && FD->getBuiltinID() == Builtin::BI__builtin_unpredictable) { diff --git a/clang/test/CodeGen/builtin-unpredictable.c b/clang/test/CodeGen/builtin-unpredictable.c index 30709b0cac6..bdd62e972b0 100644 --- a/clang/test/CodeGen/builtin-unpredictable.c +++ b/clang/test/CodeGen/builtin-unpredictable.c @@ -1,10 +1,15 @@ -// RUN: %clang_cc1 -triple x86_64-unknown-unknown -emit-llvm -disable-llvm-passes -o - %s -O1 | FileCheck %s +// RUN: %clang_cc1 -triple x86_64-unknown-unknown -emit-llvm -disable-llvm-passes -o - %s -O1 | FileCheck %s +// RUN: %clang_cc1 -triple x86_64-unknown-unknown -emit-llvm -disable-llvm-passes -o - -x c++ %s -O1 | FileCheck %s // RUN: %clang_cc1 -triple x86_64-unknown-unknown -emit-llvm -o - %s -O0 | FileCheck %s --check-prefix=CHECK_O0 // When optimizing, the builtin should be converted to metadata. // When not optimizing, there should be no metadata created for the builtin. // In both cases, the builtin should be removed from the code. +#ifdef __cplusplus +extern "C" { +#endif + void foo(); void branch(int x) { // CHECK-LABEL: define void @branch( @@ -42,5 +47,10 @@ int unpredictable_switch(int x) { return 0; } +#ifdef __cplusplus +} +#endif + + // CHECK: [[METADATA]] = !{} |