From 597dcc7a8deb329037175f79bd0bd406a2aa880b Mon Sep 17 00:00:00 2001 From: Kostya Serebryany Date: Sat, 6 Dec 2014 01:23:08 +0000 Subject: [PATCH] No memcpy for copy ctor with -fsanitize-address-field-padding=1 Summary: When -fsanitize-address-field-padding=1 is present don't emit memcpy for copy constructor. Thanks Nico for the extra test case. Test Plan: regression tests Reviewers: thakis, rsmith Reviewed By: rsmith Subscribers: rsmith, cfe-commits Differential Revision: http://reviews.llvm.org/D6515 llvm-svn: 223563 --- clang/lib/CodeGen/CGClass.cpp | 5 +++-- clang/test/CodeGen/sanitize-address-field-padding.cpp | 1 + 2 files changed, 4 insertions(+), 2 deletions(-) diff --git a/clang/lib/CodeGen/CGClass.cpp b/clang/lib/CodeGen/CGClass.cpp index dd19471..e2af17c 100644 --- a/clang/lib/CodeGen/CGClass.cpp +++ b/clang/lib/CodeGen/CGClass.cpp @@ -1735,7 +1735,7 @@ void CodeGenFunction::EmitCXXConstructorCall(const CXXConstructorDecl *D, bool Delegating, llvm::Value *This, const CXXConstructExpr *E) { // If this is a trivial constructor, just emit what's needed. - if (D->isTrivial()) { + if (D->isTrivial() && !D->getParent()->mayInsertExtraPadding()) { if (E->getNumArgs() == 0) { // Trivial default constructor, no codegen required. assert(D->isDefaultConstructor() && @@ -1785,7 +1785,8 @@ void CodeGenFunction::EmitSynthesizedCXXCopyCtorCall(const CXXConstructorDecl *D, llvm::Value *This, llvm::Value *Src, const CXXConstructExpr *E) { - if (D->isTrivial()) { + if (D->isTrivial() && + !D->getParent()->mayInsertExtraPadding()) { assert(E->getNumArgs() == 1 && "unexpected argcount for trivial ctor"); assert(D->isCopyOrMoveConstructor() && "trivial 1-arg ctor not a copy/move ctor"); diff --git a/clang/test/CodeGen/sanitize-address-field-padding.cpp b/clang/test/CodeGen/sanitize-address-field-padding.cpp index 0683089..d4eea1b 100644 --- a/clang/test/CodeGen/sanitize-address-field-padding.cpp +++ b/clang/test/CodeGen/sanitize-address-field-padding.cpp @@ -229,6 +229,7 @@ struct ClassWithTrivialCopy { void MakeTrivialCopy(ClassWithTrivialCopy *s1, ClassWithTrivialCopy *s2) { *s1 = *s2; + ClassWithTrivialCopy s3(*s2); } // CHECK-LABEL: define void @_Z15MakeTrivialCopyP20ClassWithTrivialCopyS0_ -- 2.7.4