From 0e33b4574b02c0a152567bbc384ba22f727851e8 Mon Sep 17 00:00:00 2001 From: Reid Kleckner Date: Tue, 10 Dec 2013 21:49:28 +0000 Subject: [PATCH] [asan] Fix the coverage.cc test broken by r196939 It was failing because ASan was adding all of the following to one function: - dynamic alloca - stack realignment - inline asm This patch avoids making the static alloca dynamic when coverage is used. ASan should probably not be inserting empty inline asm blobs to inhibit duplicate tail elimination. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@196973 91177308-0d34-0410-b5e6-96231b3b80d8 --- .../Instrumentation/AddressSanitizer.cpp | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git a/lib/Transforms/Instrumentation/AddressSanitizer.cpp b/lib/Transforms/Instrumentation/AddressSanitizer.cpp index 0b3ee861143..f683bfb16c7 100644 --- a/lib/Transforms/Instrumentation/AddressSanitizer.cpp +++ b/lib/Transforms/Instrumentation/AddressSanitizer.cpp @@ -1167,7 +1167,19 @@ bool AddressSanitizer::maybeInsertAsanInitAtFunctionEntry(Function &F) { // b) collect usage statistics to help improve Clang coverage design. bool AddressSanitizer::InjectCoverage(Function &F) { if (!ClCoverage) return false; - IRBuilder<> IRB(F.getEntryBlock().getFirstInsertionPt()); + + // Skip static allocas at the top of the entry block so they don't become + // dynamic when we split the block. If we used our optimized stack layout, + // then there will only be one alloca and it will come first. + BasicBlock &Entry = F.getEntryBlock(); + BasicBlock::iterator IP = Entry.getFirstInsertionPt(), BE = Entry.end(); + for (; IP != BE; ++IP) { + AllocaInst *AI = dyn_cast(IP); + if (!AI || !AI->isStaticAlloca()) + break; + } + + IRBuilder<> IRB(IP); Type *Int8Ty = IRB.getInt8Ty(); GlobalVariable *Guard = new GlobalVariable( *F.getParent(), Int8Ty, false, GlobalValue::PrivateLinkage,