Revert "Revert r234581, it might have caused a few miscompiles in Chromium."

This reverts commit r234700.  It turns out that the lifetime markers
were not the cause of Chromium failing but a bug which was uncovered by
optimizations exposed by the markers.

llvm-svn: 235553

1 files changed, 29 insertions, 0 deletions

diff --git a/clang/test/CodeGen/lifetime-debuginfo-2.c b/clang/test/CodeGen/lifetime-debuginfo-2.c
new file mode 100644
index 00000000000..db01c81db6d
--- /dev/null
+++ b/clang/test/CodeGen/lifetime-debuginfo-2.c
@@ -0,0 +1,29 @@
+// RUN: %clang_cc1 -O1 -triple x86_64-none-linux-gnu -emit-llvm -gline-tables-only %s -o - | FileCheck %s
+
+// Inserting lifetime markers should not affect debuginfo: lifetime.end is not
+// a destructor, but instrumentation for the compiler. Ensure the debug info for
+// the return statement (in the IR) does not point to the function closing '}'
+// which is used to show some destructors have been called before leaving the
+// function.
+
+extern int f(int);
+extern int g(int);
+
+// CHECK-LABEL: define i32 @test
+int test(int a, int b) {
+  int res;
+
+  if (a==2) {
+    int r = f(b);
+    res = r + b;
+    a += 2;
+  } else {
+    int r = f(a);
+    res = r + a;
+    b += 1;
+  }
+
+  return res;
+// CHECK: ret i32 %{{.*}}, !dbg [[DI:![0-9]+]]
+// CHECK: [[DI]] = !MDLocation(line: [[@LINE-2]]
+}