llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT--> @llvm/pr-subscribers-llvm-ir Author: Eli Friedman (efriedma-quic) <details> <summary>Changes</summary> With opaque pointers, nothing directly uses the value type, so we can mutate it if we want. This avoid doing a complicated RAUW dance. --- Full diff: https://github.com/llvm/llvm-project/pull/102553.diff 3 Files Affected: - (modified) clang/lib/CodeGen/CGDecl.cpp (+1-27) - (modified) llvm/include/llvm/IR/GlobalVariable.h (+8-2) - (modified) llvm/lib/IR/Globals.cpp (+6) ``````````diff diff --git a/clang/lib/CodeGen/CGDecl.cpp b/clang/lib/CodeGen/CGDecl.cpp index c3251bb5ab565..efc9e4a6d3b3d 100644 --- a/clang/lib/CodeGen/CGDecl.cpp +++ b/clang/lib/CodeGen/CGDecl.cpp @@ -370,38 +370,12 @@ CodeGenFunction::AddInitializerToStaticVarDecl(const VarDecl &D, assert(VarSize == CstSize && "Emitted constant has unexpected size"); #endif - // The initializer may differ in type from the global. Rewrite - // the global to match the initializer. (We have to do this - // because some types, like unions, can't be completely represented - // in the LLVM type system.) - if (GV->getValueType() != Init->getType()) { - llvm::GlobalVariable *OldGV = GV; - - GV = new llvm::GlobalVariable( - CGM.getModule(), Init->getType(), OldGV->isConstant(), - OldGV->getLinkage(), Init, "", - /*InsertBefore*/ OldGV, OldGV->getThreadLocalMode(), - OldGV->getType()->getPointerAddressSpace()); - GV->setVisibility(OldGV->getVisibility()); - GV->setDSOLocal(OldGV->isDSOLocal()); - GV->setComdat(OldGV->getComdat()); - - // Steal the name of the old global - GV->takeName(OldGV); - - // Replace all uses of the old global with the new global - OldGV->replaceAllUsesWith(GV); - - // Erase the old global, since it is no longer used. - OldGV->eraseFromParent(); - } - bool NeedsDtor = D.needsDestruction(getContext()) == QualType::DK_cxx_destructor; GV->setConstant( D.getType().isConstantStorage(getContext(), true, !NeedsDtor)); - GV->setInitializer(Init); + GV->replaceInitializer(Init); emitter.finalize(GV); diff --git a/llvm/include/llvm/IR/GlobalVariable.h b/llvm/include/llvm/IR/GlobalVariable.h index bcaf8e91432ba..0736c300de72f 100644 --- a/llvm/include/llvm/IR/GlobalVariable.h +++ b/llvm/include/llvm/IR/GlobalVariable.h @@ -147,10 +147,16 @@ class GlobalVariable : public GlobalObject, public ilist_node<GlobalVariable> { return static_cast<Constant*>(Op<0>().get()); } /// setInitializer - Sets the initializer for this global variable, removing - /// any existing initializer if InitVal==NULL. If this GV has type T*, the - /// initializer must have type T. + /// any existing initializer if InitVal==NULL. The initializer must have the + /// type getValueType(). void setInitializer(Constant *InitVal); + /// replaceInitializer - Sets the initializer for this global variable, and + /// sets the value type of the global to the type of the initializer. The + /// initializer must not be null. This may affect the global's alignment if + /// it isn't explicitly set. + void replaceInitializer(Constant *InitVal); + /// If the value is a global constant, its value is immutable throughout the /// runtime execution of the program. Assigning a value into the constant /// leads to undefined behavior. diff --git a/llvm/lib/IR/Globals.cpp b/llvm/lib/IR/Globals.cpp index cc37d7371cce3..2bc69cdb712b0 100644 --- a/llvm/lib/IR/Globals.cpp +++ b/llvm/lib/IR/Globals.cpp @@ -503,6 +503,12 @@ void GlobalVariable::setInitializer(Constant *InitVal) { } } +void GlobalVariable::replaceInitializer(Constant *InitVal) { + assert(InitVal && "Can't compute type of null initializer"); + ValueType = InitVal->getType(); + setInitializer(InitVal); +} + /// Copy all additional attributes (those not needed to create a GlobalVariable) /// from the GlobalVariable Src to this one. void GlobalVariable::copyAttributesFrom(const GlobalVariable *Src) { `````````` </details> https://github.com/llvm/llvm-project/pull/102553 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
