From 71e7a8ba8994e5b1f9cc0a0986b2ef5d37ed8ad2 Mon Sep 17 00:00:00 2001
From: Sylvestre Ledru <sylvestre@debian.org>
Date: Tue, 26 Sep 2017 11:56:43 +0000
Subject: [PATCH] Don't move llvm.localescape outside the entry block in the
 GCOV profiling pass

Summary:
This fixes https://bugs.llvm.org/show_bug.cgi?id=34714.

Patch by Marco Castelluccio

Reviewers: rnk

Reviewed By: rnk

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D38224

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@314201 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Transforms/Instrumentation/GCOVProfiling.cpp | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/lib/Transforms/Instrumentation/GCOVProfiling.cpp b/lib/Transforms/Instrumentation/GCOVProfiling.cpp
index b2033536ac8..3154c1939ea 100644
--- a/lib/Transforms/Instrumentation/GCOVProfiling.cpp
+++ b/lib/Transforms/Instrumentation/GCOVProfiling.cpp
@@ -502,6 +502,16 @@ static bool functionHasLines(Function &F) {
   return false;
 }
 
+static bool shouldKeepInEntry(BasicBlock::iterator It) {
+	if (isa<AllocaInst>(*It)) return true;
+	if (isa<DbgInfoIntrinsic>(*It)) return true;
+	if (auto *II = dyn_cast<IntrinsicInst>(It)) {
+		if (II->getIntrinsicID() == llvm::Intrinsic::localescape) return true;
+	}
+
+	return false;
+}
+
 void GCOVProfiler::emitProfileNotes() {
   NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
   if (!CU_Nodes) return;
@@ -537,7 +547,7 @@ void GCOVProfiler::emitProfileNotes() {
       // single successor, so split the entry block to make sure of that.
       BasicBlock &EntryBlock = F.getEntryBlock();
       BasicBlock::iterator It = EntryBlock.begin();
-      while (isa<AllocaInst>(*It) || isa<DbgInfoIntrinsic>(*It))
+      while (shouldKeepInEntry(It))
         ++It;
       EntryBlock.splitBasicBlock(It);
 
-- 
2.40.0