From 4c82a809b36bc4703a6ea2003772e1dcf2ba85c1 Mon Sep 17 00:00:00 2001 From: David Blaikie Date: Mon, 21 Apr 2014 21:27:19 +0000 Subject: Simplify destruction of Modules in LLVContextImpl. This avoids copying the container by simply deleting until empty. While I'd rather move to a stricter ownership semantic (unique_ptr), SmallPtrSet can't cope with unique_ptr and the ownership semantics here are a bit incestuous (Module sort of owns itself, but sort of doesn't (if the LLVMContext is destroyed before the Module, then it deregisters itself from the context... )). Ideally Modules would be given to the context, or possibly an emplace-like function to construct them there. Modules then shouldn't be destroyed by LLVM API clients, but by interacting with the owner (LLVMContext) directly (but even then, passing a Module* to LLVMContext doesn't provide an easy way to destroy the Module, since the set would be over unique_ptrs and you'd need a heterogenous lookup function which SmallPtrSet doesn't have either). llvm-svn: 206794 --- llvm/lib/IR/LLVMContextImpl.cpp | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) (limited to 'llvm/lib/IR/LLVMContextImpl.cpp') diff --git a/llvm/lib/IR/LLVMContextImpl.cpp b/llvm/lib/IR/LLVMContextImpl.cpp index 506b0e3..30a1ca2 100644 --- a/llvm/lib/IR/LLVMContextImpl.cpp +++ b/llvm/lib/IR/LLVMContextImpl.cpp @@ -119,12 +119,11 @@ struct DropFirst { } LLVMContextImpl::~LLVMContextImpl() { - // NOTE: We need to delete the contents of OwnedModules, but we have to - // duplicate it into a temporary vector, because the destructor of Module - // will try to remove itself from OwnedModules set. This would cause - // iterator invalidation if we iterated on the set directly. - std::vector Modules(OwnedModules.begin(), OwnedModules.end()); - DeleteContainerPointers(Modules); + // NOTE: We need to delete the contents of OwnedModules, but Module's dtor + // will call LLVMContextImpl::removeModule, thus invalidating iterators into + // the container. Avoid iterators during this operation: + while (!OwnedModules.empty()) + delete *OwnedModules.begin(); // Free the constants. This is important to do here to ensure that they are // freed before the LeakDetector is torn down. -- cgit v1.1