diff options
Diffstat (limited to 'clang/lib/CodeGen/CodeGenModule.cpp')
| -rw-r--r-- | clang/lib/CodeGen/CodeGenModule.cpp | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp index c726d90f2e3..5feb6b4d768 100644 --- a/clang/lib/CodeGen/CodeGenModule.cpp +++ b/clang/lib/CodeGen/CodeGenModule.cpp @@ -2437,6 +2437,28 @@ CodeGenModule::GetOrCreateLLVMGlobal(StringRef MangledName, D->getType().isConstant(Context) && isExternallyVisible(D->getLinkageAndVisibility().getLinkage())) GV->setSection(".cp.rodata"); + + // Check if we a have a const declaration with an initializer, we may be + // able to emit it as available_externally to expose it's value to the + // optimizer. + if (Context.getLangOpts().CPlusPlus && GV->hasExternalLinkage() && + D->getType().isConstQualified() && !GV->hasInitializer() && + !D->hasDefinition() && D->hasInit() && !D->hasAttr<DLLImportAttr>()) { + const auto *Record = + Context.getBaseElementType(D->getType())->getAsCXXRecordDecl(); + bool HasMutableFields = Record && Record->hasMutableFields(); + if (!HasMutableFields) { + const VarDecl *InitDecl; + const Expr *InitExpr = D->getAnyInitializer(InitDecl); + if (InitExpr) { + GV->setConstant(true); + GV->setLinkage(llvm::GlobalValue::AvailableExternallyLinkage); + ConstantEmitter emitter(*this); + GV->setInitializer(emitter.tryEmitForInitializer(*InitDecl)); + emitter.finalize(GV); + } + } + } } auto ExpectedAS = |
