[msan] Precise origin handling in __unaligned_(load|store)*.

llvm-svn: 205412

1 files changed, 15 insertions, 12 deletions

diff --git a/compiler-rt/lib/msan/msan.cc b/compiler-rt/lib/msan/msan.cc
index 7a93b663185..4b6578ef4ce 100644
--- a/compiler-rt/lib/msan/msan.cc
+++ b/compiler-rt/lib/msan/msan.cc
@@ -509,40 +509,43 @@ u32 __msan_get_umr_origin() {
 u16 __sanitizer_unaligned_load16(const uu16 *p) {
   __msan_retval_tls[0] = *(uu16 *)MEM_TO_SHADOW((uptr)p);
   if (__msan_get_track_origins())
-    __msan_retval_origin_tls = *(uu32 *)(MEM_TO_ORIGIN((uptr)p) & ~3UL);
+    __msan_retval_origin_tls = GetOriginIfPoisoned((uptr)p, sizeof(*p));
   return *p;
 }
 u32 __sanitizer_unaligned_load32(const uu32 *p) {
   __msan_retval_tls[0] = *(uu32 *)MEM_TO_SHADOW((uptr)p);
   if (__msan_get_track_origins())
-    __msan_retval_origin_tls = *(uu32 *)(MEM_TO_ORIGIN((uptr)p) & ~3UL);
+    __msan_retval_origin_tls = GetOriginIfPoisoned((uptr)p, sizeof(*p));
   return *p;
 }
 u64 __sanitizer_unaligned_load64(const uu64 *p) {
   __msan_retval_tls[0] = *(uu64 *)MEM_TO_SHADOW((uptr)p);
   if (__msan_get_track_origins())
-    __msan_retval_origin_tls = *(uu32 *)(MEM_TO_ORIGIN((uptr)p) & ~3UL);
+    __msan_retval_origin_tls = GetOriginIfPoisoned((uptr)p, sizeof(*p));
   return *p;
 }
 void __sanitizer_unaligned_store16(uu16 *p, u16 x) {
-  *(uu16 *)MEM_TO_SHADOW((uptr)p) = __msan_param_tls[1];
-  if (__msan_get_track_origins())
+  u16 s = __msan_param_tls[1];
+  *(uu16 *)MEM_TO_SHADOW((uptr)p) = s;
+  if (s && __msan_get_track_origins())
     if (uu32 o = __msan_param_origin_tls[2])
-      __msan_set_origin(p, 2, o);
+      SetOriginIfPoisoned((uptr)p, (uptr)&s, sizeof(s), o);
   *p = x;
 }
 void __sanitizer_unaligned_store32(uu32 *p, u32 x) {
-  *(uu32 *)MEM_TO_SHADOW((uptr)p) = __msan_param_tls[1];
-  if (__msan_get_track_origins())
+  u32 s = __msan_param_tls[1];
+  *(uu32 *)MEM_TO_SHADOW((uptr)p) = s;
+  if (s && __msan_get_track_origins())
     if (uu32 o = __msan_param_origin_tls[2])
-      __msan_set_origin(p, 4, o);
+      SetOriginIfPoisoned((uptr)p, (uptr)&s, sizeof(s), o);
   *p = x;
 }
 void __sanitizer_unaligned_store64(uu64 *p, u64 x) {
-  *(uu64 *)MEM_TO_SHADOW((uptr)p) = __msan_param_tls[1];
-  if (__msan_get_track_origins())
+  u64 s = __msan_param_tls[1];
+  *(uu64 *)MEM_TO_SHADOW((uptr)p) = s;
+  if (s && __msan_get_track_origins())
     if (uu32 o = __msan_param_origin_tls[2])
-      __msan_set_origin(p, 8, o);
+      SetOriginIfPoisoned((uptr)p, (uptr)&s, sizeof(s), o);
   *p = x;
 }