[compiler-rt] r253499 - Disable gvn non-local speculative loads under asan.

[Mike Aizatsky via llvm-commits]

Author: aizatsky
Date: Wed Nov 18 14:43:20 2015
New Revision: 253499

URL: http://llvm.org/viewvc/llvm-project?rev=253499&view=rev
Log:
Disable gvn non-local speculative loads under asan.

Summary: Fix for https://llvm.org/bugs/show_bug.cgi?id=25550

Differential Revision: http://reviews.llvm.org/D14764

Added:
    compiler-rt/trunk/test/asan/TestCases/speculative_load2.cc

Added: compiler-rt/trunk/test/asan/TestCases/speculative_load2.cc
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/test/asan/TestCases/speculative_load2.cc?rev=253499&view=auto
==============================================================================
--- compiler-rt/trunk/test/asan/TestCases/speculative_load2.cc (added)
+++ compiler-rt/trunk/test/asan/TestCases/speculative_load2.cc Wed Nov 18 14:43:20 2015
@@ -0,0 +1,21 @@
+// Verifies that speculative loads from unions do not happen under asan.
+// RUN: %clangxx_asan -O0 %s -o %t && ASAN_OPTIONS=detect_leaks=0 %run %t 2>&1
+// RUN: %clangxx_asan -O1 %s -o %t && ASAN_OPTIONS=detect_leaks=0 %run %t 2>&1
+// RUN: %clangxx_asan -O2 %s -o %t && ASAN_OPTIONS=detect_leaks=0 %run %t 2>&1
+// RUN: %clangxx_asan -O3 %s -o %t && ASAN_OPTIONS=detect_leaks=0 %run %t 2>&1
+
+typedef union {
+  short q;
+  struct {
+    short x;
+    short y;
+    int for_alignment;
+  } w;
+} U;
+int main() {
+  char *buf = new char[2];
+  buf[0] = buf[1] = 0x0;
+  U *u = (U *)buf;
+  return  u->q == 0 ? 0 : u->w.y;
+}
+