[msan] Cleanup public interface header.

Moved everything users are not supposed to use to a private interface header.
Documented all public interfaces. Made them safe to use even if built without
MemorySanitizer.

llvm-svn: 173800

8 files changed, 261 insertions, 142 deletions

diff --git a/compiler-rt/include/sanitizer/msan_interface.h b/compiler-rt/include/sanitizer/msan_interface.h
index 601dba16b3c..a6a0bcf7d7b 100644
--- a/compiler-rt/include/sanitizer/msan_interface.h
+++ b/compiler-rt/include/sanitizer/msan_interface.h
@@ -24,103 +24,99 @@ using __sanitizer::u32;
 extern "C" {
 #endif
 
-// FIXME: document all interface functions.
-
-SANITIZER_INTERFACE_ATTRIBUTE
-int __msan_get_track_origins();
-
-SANITIZER_INTERFACE_ATTRIBUTE
-void __msan_init();
-
-// Print a warning and maybe return.
-// This function can die based on flags()->exit_code.
-SANITIZER_INTERFACE_ATTRIBUTE
-void __msan_warning();
-
-// Print a warning and die.
-// Intrumentation inserts calls to this function when building in "fast" mode
-// (i.e. -mllvm -msan-keep-going)
-SANITIZER_INTERFACE_ATTRIBUTE __attribute__((noreturn))
-void __msan_warning_noreturn();
-
-SANITIZER_INTERFACE_ATTRIBUTE
-void __msan_unpoison(void *a, uptr size);
-SANITIZER_INTERFACE_ATTRIBUTE
-void __msan_clear_and_unpoison(void *a, uptr size);
-SANITIZER_INTERFACE_ATTRIBUTE
-void* __msan_memcpy(void *dst, const void *src, uptr size);
-SANITIZER_INTERFACE_ATTRIBUTE
-void* __msan_memset(void *s, int c, uptr n);
-SANITIZER_INTERFACE_ATTRIBUTE
-void* __msan_memmove(void* dest, const void* src, uptr n);
-SANITIZER_INTERFACE_ATTRIBUTE
-void __msan_copy_poison(void *dst, const void *src, uptr size);
-SANITIZER_INTERFACE_ATTRIBUTE
-void __msan_copy_origin(void *dst, const void *src, uptr size);
-SANITIZER_INTERFACE_ATTRIBUTE
-void __msan_move_poison(void *dst, const void *src, uptr size);
-SANITIZER_INTERFACE_ATTRIBUTE
-void __msan_poison(void *a, uptr size);
-SANITIZER_INTERFACE_ATTRIBUTE
-void __msan_poison_stack(void *a, uptr size);
-
-// Copy size bytes from src to dst and unpoison the result.
-// Useful to implement unsafe loads.
-SANITIZER_INTERFACE_ATTRIBUTE
-void __msan_load_unpoisoned(void *src, uptr size, void *dst);
-
-// Returns the offset of the first (at least partially) poisoned byte,
-// or -1 if the whole range is good.
-SANITIZER_INTERFACE_ATTRIBUTE
-sptr __msan_test_shadow(const void *x, uptr size);
-
-SANITIZER_INTERFACE_ATTRIBUTE
-void __msan_set_origin(void *a, uptr size, u32 origin);
-SANITIZER_INTERFACE_ATTRIBUTE
-void __msan_set_alloca_origin(void *a, uptr size, const char *descr);
-SANITIZER_INTERFACE_ATTRIBUTE
-u32 __msan_get_origin(void *a);
-
-SANITIZER_INTERFACE_ATTRIBUTE
-void __msan_clear_on_return();
-
-// Default: -1 (don't exit on error).
-SANITIZER_INTERFACE_ATTRIBUTE
-void __msan_set_exit_code(int exit_code);
-
-SANITIZER_INTERFACE_ATTRIBUTE
-int __msan_set_poison_in_malloc(int do_poison);
-
-// For testing.
-SANITIZER_INTERFACE_ATTRIBUTE
-void __msan_set_expect_umr(int expect_umr);
-SANITIZER_INTERFACE_ATTRIBUTE
-void __msan_break_optimization(void *x);
-SANITIZER_INTERFACE_ATTRIBUTE
-void __msan_print_shadow(const void *x, uptr size);
-SANITIZER_INTERFACE_ATTRIBUTE
-void __msan_print_param_shadow();
-SANITIZER_INTERFACE_ATTRIBUTE
-int  __msan_has_dynamic_component();
-
-// Returns x such that %fs:x is the first byte of __msan_retval_tls.
-SANITIZER_INTERFACE_ATTRIBUTE
-int __msan_get_retval_tls_offset();
-SANITIZER_INTERFACE_ATTRIBUTE
-int __msan_get_param_tls_offset();
-
-// For testing.
-SANITIZER_INTERFACE_ATTRIBUTE
-u32 __msan_get_origin_tls();
-SANITIZER_INTERFACE_ATTRIBUTE
-const char *__msan_get_origin_descr_if_stack(u32 id);
-SANITIZER_INTERFACE_ATTRIBUTE
-void __msan_partial_poison(void* data, void* shadow, uptr size);
-
-// Tell MSan about newly allocated memory (ex.: custom allocator).
-// Memory will be marked uninitialized, with origin at the call site.
-SANITIZER_INTERFACE_ATTRIBUTE
-void __msan_allocated_memory(void* data, uptr size);
+#if defined(__has_feature) && __has_feature(memory_sanitizer)
+
+  /* Returns a string describing a stack origin.
+     Return NULL if the origin is invalid, or is not a stack origin. */
+  SANITIZER_INTERFACE_ATTRIBUTE
+  const char *__msan_get_origin_descr_if_stack(u32 id);
+
+
+  /* Set raw origin for the memory range. */
+  SANITIZER_INTERFACE_ATTRIBUTE
+  void __msan_set_origin(void *a, uptr size, u32 origin);
+
+  /* Get raw origin for an address. */
+  SANITIZER_INTERFACE_ATTRIBUTE
+  u32 __msan_get_origin(void *a);
+
+  /* Returns non-zero if tracking origins. */
+  SANITIZER_INTERFACE_ATTRIBUTE
+  int __msan_get_track_origins();
+
+  /* Returns the origin id of the latest UMR in the calling thread. */
+  SANITIZER_INTERFACE_ATTRIBUTE
+  u32 __msan_get_umr_origin();
+
+  /* Make memory region fully initialized (without changing its contents). */
+  SANITIZER_INTERFACE_ATTRIBUTE
+  void __msan_unpoison(void *a, uptr size);
+
+  /* Make memory region fully uninitialized (without changing its contents). */
+  SANITIZER_INTERFACE_ATTRIBUTE
+  void __msan_poison(void *a, uptr size);
+
+  /* Make memory region partially uninitialized (without changing its contents).
+   */
+  SANITIZER_INTERFACE_ATTRIBUTE
+  void __msan_partial_poison(void* data, void* shadow, uptr size);
+
+  /* Returns the offset of the first (at least partially) poisoned byte in the
+     memory range, or -1 if the whole range is good. */
+  SANITIZER_INTERFACE_ATTRIBUTE
+  sptr __msan_test_shadow(const void *x, uptr size);
+
+  /* Set exit code when error(s) were detected.
+     Value of 0 means don't change the program exit code. */
+  SANITIZER_INTERFACE_ATTRIBUTE
+  void __msan_set_exit_code(int exit_code);
+
+  /* For testing:
+     __msan_set_expect_umr(1);
+     ... some buggy code ...
+     __msan_set_expect_umr(0);
+     The last line will verify that a UMR happened. */
+  SANITIZER_INTERFACE_ATTRIBUTE
+  void __msan_set_expect_umr(int expect_umr);
+
+  /* Print shadow and origin for the memory range to stdout in a human-readable
+     format. */
+  SANITIZER_INTERFACE_ATTRIBUTE
+  void __msan_print_shadow(const void *x, uptr size);
+
+  /* Print current function arguments shadow and origin to stdout in a
+     human-readable format. */
+  SANITIZER_INTERFACE_ATTRIBUTE
+  void __msan_print_param_shadow();
+
+  /* Returns true if running under a dynamic tool (DynamoRio-based). */
+  SANITIZER_INTERFACE_ATTRIBUTE
+  int  __msan_has_dynamic_component();
+
+  /* Tell MSan about newly allocated memory (ex.: custom allocator).
+     Memory will be marked uninitialized, with origin at the call site. */
+  SANITIZER_INTERFACE_ATTRIBUTE
+  void __msan_allocated_memory(void* data, uptr size);
+
+#else  // __has_feature(memory_sanitizer)
+
+#define __msan_get_origin_descr_if_stack(u32 id) ((const char*)0)
+#define __msan_set_origin(void *a, uptr size, u32 origin)
+#define __msan_get_origin(void *a) ((u32)-1)
+#define __msan_get_track_origins() (0)
+#define __msan_get_umr_origin() ((u32)-1)
+#define __msan_unpoison(void *a, uptr size)
+#define __msan_poison(void *a, uptr size)
+#define __msan_partial_poison(void* data, void* shadow, uptr size)
+#define __msan_test_shadow(const void *x, uptr size) ((sptr)-1)
+#define __msan_set_exit_code(int exit_code)
+#define __msan_set_expect_umr(int expect_umr)
+#define __msan_print_shadow(const void *x, uptr size)
+#define __msan_print_param_shadow()
+#define __msan_has_dynamic_component() (0)
+#define __msan_allocated_memory(data, size)
+
+#endif   // __has_feature(memory_sanitizer)
 
 #ifdef __cplusplus
 }  // extern "C"
diff --git a/compiler-rt/lib/msan/msan.cc b/compiler-rt/lib/msan/msan.cc
index 85fdc22ed8b..f2cde3f928d 100644
--- a/compiler-rt/lib/msan/msan.cc
+++ b/compiler-rt/lib/msan/msan.cc
@@ -306,8 +306,6 @@ int __msan_set_poison_in_malloc(int do_poison) {
   return old;
 }
 
-void __msan_break_optimization(void *x) { }
-
 int  __msan_has_dynamic_component() {
   return msan_running_under_dr;
 }
@@ -413,6 +411,6 @@ u32 __msan_get_origin(void *a) {
   return *(u32*)origin_ptr;
 }
 
-u32 __msan_get_origin_tls() {
+u32 __msan_get_umr_origin() {
   return __msan_origin_tls;
 }
diff --git a/compiler-rt/lib/msan/msan.h b/compiler-rt/lib/msan/msan.h
index 99d9a90d2dc..eafe7025737 100644
--- a/compiler-rt/lib/msan/msan.h
+++ b/compiler-rt/lib/msan/msan.h
@@ -17,7 +17,7 @@
 
 #include "sanitizer_common/sanitizer_internal_defs.h"
 #include "sanitizer_common/sanitizer_stacktrace.h"
-#include "sanitizer/msan_interface.h"
+#include "msan_interface_internal.h"
 #include "msan_flags.h"
 
 #define MEM_TO_SHADOW(mem) (((uptr)mem)       & ~0x400000000000ULL)
diff --git a/compiler-rt/lib/msan/msan_interface_internal.h b/compiler-rt/lib/msan/msan_interface_internal.h
new file mode 100644
index 00000000000..a259ef688c7
--- /dev/null
+++ b/compiler-rt/lib/msan/msan_interface_internal.h
@@ -0,0 +1,120 @@
+//===-- msan_interface_internal.h -------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file is a part of MemorySanitizer.
+//
+// Private MSan interface header.
+//===----------------------------------------------------------------------===//
+
+#ifndef MSAN_INTERFACE_INTERNAL_H
+#define MSAN_INTERFACE_INTERNAL_H
+
+#include <sanitizer/common_interface_defs.h>
+
+extern "C" {
+
+// FIXME: document all interface functions.
+
+SANITIZER_INTERFACE_ATTRIBUTE
+int __msan_get_track_origins();
+
+SANITIZER_INTERFACE_ATTRIBUTE
+void __msan_init();
+
+// Print a warning and maybe return.
+// This function can die based on flags()->exit_code.
+SANITIZER_INTERFACE_ATTRIBUTE
+void __msan_warning();
+
+// Print a warning and die.
+// Intrumentation inserts calls to this function when building in "fast" mode
+// (i.e. -mllvm -msan-keep-going)
+SANITIZER_INTERFACE_ATTRIBUTE __attribute__((noreturn))
+void __msan_warning_noreturn();
+
+SANITIZER_INTERFACE_ATTRIBUTE
+void __msan_unpoison(void *a, uptr size);
+SANITIZER_INTERFACE_ATTRIBUTE
+void __msan_clear_and_unpoison(void *a, uptr size);
+SANITIZER_INTERFACE_ATTRIBUTE
+void* __msan_memcpy(void *dst, const void *src, uptr size);
+SANITIZER_INTERFACE_ATTRIBUTE
+void* __msan_memset(void *s, int c, uptr n);
+SANITIZER_INTERFACE_ATTRIBUTE
+void* __msan_memmove(void* dest, const void* src, uptr n);
+SANITIZER_INTERFACE_ATTRIBUTE
+void __msan_copy_poison(void *dst, const void *src, uptr size);
+SANITIZER_INTERFACE_ATTRIBUTE
+void __msan_copy_origin(void *dst, const void *src, uptr size);
+SANITIZER_INTERFACE_ATTRIBUTE
+void __msan_move_poison(void *dst, const void *src, uptr size);
+SANITIZER_INTERFACE_ATTRIBUTE
+void __msan_poison(void *a, uptr size);
+SANITIZER_INTERFACE_ATTRIBUTE
+void __msan_poison_stack(void *a, uptr size);
+
+// Copy size bytes from src to dst and unpoison the result.
+// Useful to implement unsafe loads.
+SANITIZER_INTERFACE_ATTRIBUTE
+void __msan_load_unpoisoned(void *src, uptr size, void *dst);
+
+// Returns the offset of the first (at least partially) poisoned byte,
+// or -1 if the whole range is good.
+SANITIZER_INTERFACE_ATTRIBUTE
+sptr __msan_test_shadow(const void *x, uptr size);
+
+SANITIZER_INTERFACE_ATTRIBUTE
+void __msan_set_origin(void *a, uptr size, u32 origin);
+SANITIZER_INTERFACE_ATTRIBUTE
+void __msan_set_alloca_origin(void *a, uptr size, const char *descr);
+SANITIZER_INTERFACE_ATTRIBUTE
+u32 __msan_get_origin(void *a);
+
+SANITIZER_INTERFACE_ATTRIBUTE
+void __msan_clear_on_return();
+
+// Default: -1 (don't exit on error).
+SANITIZER_INTERFACE_ATTRIBUTE
+void __msan_set_exit_code(int exit_code);
+
+SANITIZER_INTERFACE_ATTRIBUTE
+int __msan_set_poison_in_malloc(int do_poison);
+
+// For testing.
+SANITIZER_INTERFACE_ATTRIBUTE
+void __msan_set_expect_umr(int expect_umr);
+SANITIZER_INTERFACE_ATTRIBUTE
+void __msan_print_shadow(const void *x, uptr size);
+SANITIZER_INTERFACE_ATTRIBUTE
+void __msan_print_param_shadow();
+SANITIZER_INTERFACE_ATTRIBUTE
+int  __msan_has_dynamic_component();
+
+// Returns x such that %fs:x is the first byte of __msan_retval_tls.
+SANITIZER_INTERFACE_ATTRIBUTE
+int __msan_get_retval_tls_offset();
+SANITIZER_INTERFACE_ATTRIBUTE
+int __msan_get_param_tls_offset();
+
+// For testing.
+SANITIZER_INTERFACE_ATTRIBUTE
+u32 __msan_get_umr_origin();
+SANITIZER_INTERFACE_ATTRIBUTE
+const char *__msan_get_origin_descr_if_stack(u32 id);
+SANITIZER_INTERFACE_ATTRIBUTE
+void __msan_partial_poison(void* data, void* shadow, uptr size);
+
+// Tell MSan about newly allocated memory (ex.: custom allocator).
+// Memory will be marked uninitialized, with origin at the call site.
+SANITIZER_INTERFACE_ATTRIBUTE
+void __msan_allocated_memory(void* data, uptr size);
+
+}  // extern "C"
+
+#endif  // MSAN_INTERFACE_INTERNAL_H
diff --git a/compiler-rt/lib/msan/tests/CMakeLists.txt b/compiler-rt/lib/msan/tests/CMakeLists.txt
index 461e5918eee..f2be64780e9 100644
--- a/compiler-rt/lib/msan/tests/CMakeLists.txt
+++ b/compiler-rt/lib/msan/tests/CMakeLists.txt
@@ -32,7 +32,10 @@ set(MSAN_LIBCXX_LINK_FLAGS
 
 # Unittest sources and build flags.
 set(MSAN_UNITTEST_SOURCE msan_test.cc)
-set(MSAN_UNITTEST_HEADERS msandr_test_so.h)
+set(MSAN_UNITTEST_HEADERS
+  msandr_test_so.h
+  ../../../include/sanitizer/msan_interface.h
+)
 set(MSANDR_UNITTEST_SOURCE msandr_test_so.cc)
 set(MSAN_UNITTEST_COMMON_CFLAGS
   -I${MSAN_LIBCXX_PATH}/include
diff --git a/compiler-rt/lib/msan/tests/msan_test.cc b/compiler-rt/lib/msan/tests/msan_test.cc
index 4dbe291cf96..3adf70940d6 100644
--- a/compiler-rt/lib/msan/tests/msan_test.cc
+++ b/compiler-rt/lib/msan/tests/msan_test.cc
@@ -74,7 +74,7 @@ static bool TrackingOrigins() {
       action;                                       \
       __msan_set_expect_umr(0);                     \
       if (TrackingOrigins())                        \
-        EXPECT_EQ(origin, __msan_get_origin_tls()); \
+        EXPECT_EQ(origin, __msan_get_umr_origin()); \
     } while (0)
 
 #define EXPECT_UMR_S(action, stack_origin) \
@@ -82,7 +82,7 @@ static bool TrackingOrigins() {
       __msan_set_expect_umr(1);                     \
       action;                                       \
       __msan_set_expect_umr(0);                     \
-      u32 id = __msan_get_origin_tls();             \
+      u32 id = __msan_get_umr_origin();             \
       const char *str = __msan_get_origin_descr_if_stack(id); \
       if (!str || strcmp(str, stack_origin)) {      \
         fprintf(stderr, "EXPECT_POISONED_S: id=%u %s, %s", \
@@ -167,6 +167,14 @@ static volatile int g_1 = 1;
 S4 a_s4[100];
 S8 a_s8[100];
 
+// Check that malloc poisons memory.
+// A lot of tests below depend on this.
+TEST(MemorySanitizerSanity, PoisonInMalloc) {
+  int *x = (int*)malloc(sizeof(int));
+  EXPECT_POISONED(*x);
+  free(x);
+}
+
 TEST(MemorySanitizer, NegativeTest1) {
   S4 *x = GetPoisoned<S4>();
   if (g_one)
@@ -221,7 +229,7 @@ TEST(MemorySanitizer, Phi1) {
   if (g_one) {
     c = *GetPoisoned<S4>();
   } else {
-    __msan_break_optimization(0);
+    break_optimization(0);
     c = 0;
   }
   EXPECT_POISONED(c);
@@ -393,14 +401,14 @@ NOINLINE static int GetPoisonedZero() {
 TEST(MemorySanitizer, LoadFromDirtyAddress) {
   int *a = new int;
   *a = 0;
-  EXPECT_UMR(__msan_break_optimization((void*)(U8)a[GetPoisonedZero()]));
+  EXPECT_UMR(break_optimization((void*)(U8)a[GetPoisonedZero()]));
   delete a;
 }
 
 TEST(MemorySanitizer, StoreToDirtyAddress) {
   int *a = new int;
   EXPECT_UMR(a[GetPoisonedZero()] = 0);
-  __msan_break_optimization(a);
+  break_optimization(a);
   delete a;
 }
 
@@ -412,12 +420,12 @@ NOINLINE void StackTestFunc() {
   S2 ok2 = 1;
   S1 p1;
   S1 ok1 = 1;
-  __msan_break_optimization(&p4);
-  __msan_break_optimization(&ok4);
-  __msan_break_optimization(&p2);
-  __msan_break_optimization(&ok2);
-  __msan_break_optimization(&p1);
-  __msan_break_optimization(&ok1);
+  break_optimization(&p4);
+  break_optimization(&ok4);
+  break_optimization(&p2);
+  break_optimization(&ok2);
+  break_optimization(&p1);
+  break_optimization(&ok1);
 
   EXPECT_POISONED(p4);
   EXPECT_POISONED(p2);
@@ -433,7 +441,7 @@ TEST(MemorySanitizer, StackTest) {
 
 NOINLINE void StackStressFunc() {
   int foo[10000];
-  __msan_break_optimization(foo);
+  break_optimization(foo);
 }
 
 TEST(MemorySanitizer, DISABLED_StackStressTest) {
@@ -445,7 +453,7 @@ template<class T>
 void TestFloatingPoint() {
   static volatile T v;
   static T g[100];
-  __msan_break_optimization(&g);
+  break_optimization(&g);
   T *x = GetPoisoned<T>();
   T *y = GetPoisoned<T>(1);
   EXPECT_POISONED(*x);
@@ -723,7 +731,7 @@ TEST(MemorySanitizer, strtold) {
 
 TEST(MemorySanitizer, sprintf) {  // NOLINT
   char buff[10];
-  __msan_break_optimization(buff);
+  break_optimization(buff);
   EXPECT_POISONED(buff[0]);
   int res = sprintf(buff, "%d", 1234567);  // NOLINT
   assert(res == 7);
@@ -737,7 +745,7 @@ TEST(MemorySanitizer, sprintf) {  // NOLINT
 
 TEST(MemorySanitizer, snprintf) {
   char buff[10];
-  __msan_break_optimization(buff);
+  break_optimization(buff);
   EXPECT_POISONED(buff[0]);
   int res = snprintf(buff, sizeof(buff), "%d", 1234567);
   assert(res == 7);
@@ -752,7 +760,7 @@ TEST(MemorySanitizer, snprintf) {
 TEST(MemorySanitizer, swprintf) {
   wchar_t buff[10];
   assert(sizeof(wchar_t) == 4);
-  __msan_break_optimization(buff);
+  break_optimization(buff);
   EXPECT_POISONED(buff[0]);
   int res = swprintf(buff, 9, L"%d", 1234567);
   assert(res == 7);
@@ -777,8 +785,8 @@ TEST(MemorySanitizer, wcstombs) {
 TEST(MemorySanitizer, gettimeofday) {
   struct timeval tv;
   struct timezone tz;
-  __msan_break_optimization(&tv);
-  __msan_break_optimization(&tz);
+  break_optimization(&tv);
+  break_optimization(&tz);
   assert(sizeof(tv) == 16);
   assert(sizeof(tz) == 8);
   EXPECT_POISONED(tv.tv_sec);
@@ -815,8 +823,8 @@ TEST(MemorySanitizer, mmap) {
 // FIXME: check why msandr does nt handle fcvt.
 TEST(MemorySanitizer, fcvt) {
   int a, b;
-  __msan_break_optimization(&a);
-  __msan_break_optimization(&b);
+  break_optimization(&a);
+  break_optimization(&b);
   EXPECT_POISONED(a);
   EXPECT_POISONED(b);
   char *str = fcvt(12345.6789, 10, &a, &b);
@@ -824,20 +832,12 @@ TEST(MemorySanitizer, fcvt) {
   EXPECT_NOT_POISONED(b);
 }
 
-TEST(MemorySanitizer, LoadUnpoisoned) {
-  S8 s = *GetPoisoned<S8>();
-  EXPECT_POISONED(s);
-  S8 safe = *GetPoisoned<S8>();
-  __msan_load_unpoisoned(&s, sizeof(s), &safe);
-  EXPECT_NOT_POISONED(safe);
-}
-
 struct StructWithDtor {
   ~StructWithDtor();
 };
 
 NOINLINE StructWithDtor::~StructWithDtor() {
-  __msan_break_optimization(0);
+  break_optimization(0);
 }
 
 TEST(MemorySanitizer, Invoke) {
@@ -1106,7 +1106,7 @@ NOINLINE StructWithHole ReturnStructWithHole() {
 
 TEST(MemorySanitizer, StructWithHole) {
   StructWithHole a = ReturnStructWithHole();
-  __msan_break_optimization(&a);
+  break_optimization(&a);
 }
 
 template <class T>
@@ -1518,7 +1518,7 @@ void BinaryOpOriginTest(BinaryOp op) {
   // y is poisoned, x is not.
   *x = 10101;
   *y = *GetPoisonedO<T>(1, oy);
-  __msan_break_optimization(x);
+  break_optimization(x);
   __msan_set_origin(z, sizeof(*z), 0);
   *z = op(*x, *y);
   EXPECT_POISONED_O(*z, oy);
@@ -1527,7 +1527,7 @@ void BinaryOpOriginTest(BinaryOp op) {
   // x is poisoned, y is not.
   *x = *GetPoisonedO<T>(0, ox);
   *y = 10101010;
-  __msan_break_optimization(y);
+  break_optimization(y);
   __msan_set_origin(z, sizeof(*z), 0);
   *z = op(*x, *y);
   EXPECT_POISONED_O(*z, ox);
@@ -1645,7 +1645,7 @@ TEST(MemorySanitizerOrigins, Select) {
   EXPECT_NOT_POISONED(g_one ? 1 : *GetPoisonedO<S4>(0, __LINE__));
   EXPECT_POISONED_O(*GetPoisonedO<S4>(0, __LINE__), __LINE__);
   S4 x;
-  __msan_break_optimization(&x);
+  break_optimization(&x);
   x = g_1 ? *GetPoisonedO<S4>(0, __LINE__) : 0;
 
   EXPECT_POISONED_O(g_1 ? *GetPoisonedO<S4>(0, __LINE__) : 1, __LINE__);
@@ -1655,7 +1655,7 @@ TEST(MemorySanitizerOrigins, Select) {
 extern "C"
 NOINLINE char AllocaTO() {
   int ar[100];
-  __msan_break_optimization(ar);
+  break_optimization(ar);
   return ar[10];
   // fprintf(stderr, "Descr: %s\n",
   //        __msan_get_origin_descr_if_stack(__msan_get_origin_tls()));
@@ -1677,7 +1677,7 @@ TEST(MemorySanitizerOrigins, DISABLED_AllocaDeath) {
 
 NOINLINE int RetvalOriginTest(u32 origin) {
   int *a = new int;
-  __msan_break_optimization(a);
+  break_optimization(a);
   __msan_set_origin(a, sizeof(*a), origin);
   int res = *a;
   delete a;
@@ -1697,7 +1697,7 @@ TEST(MemorySanitizerOrigins, Param) {
   if (!TrackingOrigins()) return;
   int *a = new int;
   u32 origin = __LINE__;
-  __msan_break_optimization(a);
+  break_optimization(a);
   __msan_set_origin(a, sizeof(*a), origin);
   ParamOriginTest(*a, origin);
   delete a;
@@ -1711,7 +1711,7 @@ TEST(MemorySanitizerOrigins, Invoke) {
 
 TEST(MemorySanitizerOrigins, strlen) {
   S8 alignment;
-  __msan_break_optimization(&alignment);
+  break_optimization(&alignment);
   char x[4] = {'a', 'b', 0, 0};
   __msan_poison(&x[2], 1);
   u32 origin = __LINE__;
@@ -1745,8 +1745,8 @@ NOINLINE void RecursiveMalloc(int depth) {
     printf("RecursiveMalloc: %d\n", count);
   int *x1 = new int;
   int *x2 = new int;
-  __msan_break_optimization(x1);
-  __msan_break_optimization(x2);
+  break_optimization(x1);
+  break_optimization(x2);
   if (depth > 0) {
     RecursiveMalloc(depth-1);
     RecursiveMalloc(depth-1);
@@ -1768,7 +1768,6 @@ TEST(MemorySanitizerStress, DISABLED_MallocStackTrace) {
 }
 
 int main(int argc, char **argv) {
-  __msan_set_poison_in_malloc(1);
   testing::InitGoogleTest(&argc, argv);
   int res = RUN_ALL_TESTS();
   return res;
diff --git a/compiler-rt/lib/msan/tests/msandr_test_so.cc b/compiler-rt/lib/msan/tests/msandr_test_so.cc
index fddd8ded896..eb605d4dba1 100644
--- a/compiler-rt/lib/msan/tests/msandr_test_so.cc
+++ b/compiler-rt/lib/msan/tests/msandr_test_so.cc
@@ -34,3 +34,5 @@ int dso_stack_store(void (*fn)(int*, int*), int x) {
   fn(&x, &y);
   return y;
 }
+
+void break_optimization(void *x) {}
diff --git a/compiler-rt/lib/msan/tests/msandr_test_so.h b/compiler-rt/lib/msan/tests/msandr_test_so.h
index 6119542ee50..cd75ff34f38 100644
--- a/compiler-rt/lib/msan/tests/msandr_test_so.h
+++ b/compiler-rt/lib/msan/tests/msandr_test_so.h
@@ -19,5 +19,6 @@ void dso_memfill(char* s, unsigned n);
 int dso_callfn(int (*fn)(void));
 int dso_callfn1(int (*fn)(long long, long long, long long));  //NOLINT
 int dso_stack_store(void (*fn)(int*, int*), int x);
+void break_optimization(void *x);
 
 #endif