From 28f747a6081cf2f6104443872d6ffe4673665718 Mon Sep 17 00:00:00 2001
From: Dan Gohman <gohman@apple.com>
Date: Mon, 19 Jul 2010 22:48:56 +0000
Subject: [PATCH] After a custom inserter, in a block which has constant
 instructions, update the current basic block in addition to the current
 insert position, so that they remain consistent. This fixes rdar://8204072.

llvm-svn: 108765
---
 lib/CodeGen/SelectionDAG/FastISel.cpp |  1 +
 test/CodeGen/X86/fast-isel-atomic.ll  | 16 ++++++++++++++++
 2 files changed, 17 insertions(+)
 create mode 100644 test/CodeGen/X86/fast-isel-atomic.ll

diff --git a/lib/CodeGen/SelectionDAG/FastISel.cpp b/lib/CodeGen/SelectionDAG/FastISel.cpp
index cff7ace536a..1fb20f1dc06 100644
--- a/lib/CodeGen/SelectionDAG/FastISel.cpp
+++ b/lib/CodeGen/SelectionDAG/FastISel.cpp
@@ -276,6 +276,7 @@ std::pair<unsigned, bool> FastISel::getRegForGEPIndex(const Value *Idx) {
 void FastISel::recomputeInsertPt() {
   if (getLastLocalValue()) {
     FuncInfo.InsertPt = getLastLocalValue();
+    FuncInfo.MBB = FuncInfo.InsertPt->getParent();
     ++FuncInfo.InsertPt;
   } else
     FuncInfo.InsertPt = FuncInfo.MBB->getFirstNonPHI();
diff --git a/test/CodeGen/X86/fast-isel-atomic.ll b/test/CodeGen/X86/fast-isel-atomic.ll
new file mode 100644
index 00000000000..f8eee9caa6a
--- /dev/null
+++ b/test/CodeGen/X86/fast-isel-atomic.ll
@@ -0,0 +1,16 @@
+; RUN: llc < %s -O0 -march=x86-64
+; rdar://8204072
+
+@sc = external global i8
+@uc = external global i8
+
+declare i8 @llvm.atomic.load.and.i8.p0i8(i8* nocapture, i8) nounwind
+
+define void @test_fetch_and_op() nounwind {
+entry:
+  %tmp40 = call i8 @llvm.atomic.load.and.i8.p0i8(i8* @sc, i8 11) ; <i8> [#uses=1]
+  store i8 %tmp40, i8* @sc
+  %tmp41 = call i8 @llvm.atomic.load.and.i8.p0i8(i8* @uc, i8 11) ; <i8> [#uses=1]
+  store i8 %tmp41, i8* @uc
+  ret void
+}