Failing assertions is unlikely (pytorch#20876)

Summary: Pull Request resolved: pytorch#20876 Tell the compiler that assertions are likely to succeed. This allows the compiler to generate betterr code and optimize for the success case. Differential Revision: D15480066 fbshipit-source-id: 4485154d66b2ee0ef8a401718712dbd61d811aee
IvanKobzarev · May 29, 2019 · 99b057d · 99b057d
1 parent 9daf485
commit 99b057d
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Showing 2 changed files with 12 additions and 12 deletions.
diff --git a/c10/util/Exception.h b/c10/util/Exception.h
@@ -171,15 +171,15 @@ inline std::string if_empty_then(std::string x, std::string y) {
 //
 #ifdef C10_MOBILE
 #define TORCH_INTERNAL_ASSERT(cond, ...)      \
-  if (!(cond)) {                              \
+  if (C10_UNLIKELY(!(cond))) {                \
     C10_THROW_ERROR(Error,                    \
         #cond " INTERNAL ASSERT FAILED at"    \
         __FILE__                              \
     );                                        \
   }
 #else
 #define TORCH_INTERNAL_ASSERT(cond, ...)      \
-  if (!(cond)) {                              \
+  if (C10_UNLIKELY(!(cond))) {                \
     C10_THROW_ERROR(Error, ::c10::str(        \
         #cond " INTERNAL ASSERT FAILED at ",  \
         __FILE__,                             \
@@ -213,23 +213,23 @@ inline std::string if_empty_then(std::string x, std::string y) {
 //
 #ifdef C10_MOBILE
 #define TORCH_CHECK(cond, ...)                \
-  if (!(cond)) {                              \
+  if (C10_UNLIKELY(!(cond))) {                \
     C10_THROW_ERROR(Error,                    \
         #cond " CHECK FAILED at "             \
         __FILE__                              \
     );                                        \
   }
 #else
 #define TORCH_CHECK(cond, ...)                              \
-  if (!(cond)) {                                            \
+  if (C10_UNLIKELY(!(cond))) {                              \
     C10_THROW_ERROR(Error,                                  \
       ::c10::detail::if_empty_then(                         \
         ::c10::str(__VA_ARGS__),                            \
         "Expected " #cond " to be true, but got false.  "   \
         "(Could this error message be improved?  If so, "   \
         "please report an enhancement request to PyTorch.)" \
-      ) \
-    ); \
+      )                                                     \
+    );                                                      \
   }
 #endif
 // TODO: We're going to get a lot of similar looking string literals
@@ -238,15 +238,15 @@ inline std::string if_empty_then(std::string x, std::string y) {
 // Like TORCH_CHECK, but raises IndexErrors instead of Errors.
 #ifdef C10_MOBILE
 #define TORCH_CHECK_INDEX(cond, ...)          \
-  if (!(cond)) {                              \
+  if (C10_UNLIKELY(!(cond))) {                \
     C10_THROW_ERROR(Error,                    \
         #cond " INDEX CHECK FAILED at "       \
         __FILE__                              \
     );                                        \
   }
 #else
 #define TORCH_CHECK_INDEX(cond, ...)                        \
-  if (!(cond)) {                                            \
+  if (C10_UNLIKELY(!(cond))) {                              \
     C10_THROW_ERROR(IndexError,                             \
       ::c10::detail::if_empty_then(                         \
         ::c10::str(__VA_ARGS__),                            \

diff --git a/c10/util/Logging.h b/c10/util/Logging.h
@@ -86,15 +86,15 @@ using EnforceNotMet = ::c10::Error;
 
 #define CAFFE_ENFORCE(condition, ...)                               \
   do {                                                              \
-    if (!(condition)) {                                             \
+    if (C10_UNLIKELY(!(condition))) {                               \
       ::c10::ThrowEnforceNotMet(                                    \
           __FILE__, __LINE__, #condition, ::c10::str(__VA_ARGS__)); \
     }                                                               \
   } while (false)
 
 #define CAFFE_ENFORCE_WITH_CALLER(condition, ...)                         \
   do {                                                                    \
-    if (!(condition)) {                                                   \
+    if (C10_UNLIKELY(!(condition))) {                                     \
       ::c10::ThrowEnforceNotMet(                                          \
           __FILE__, __LINE__, #condition, ::c10::str(__VA_ARGS__), this); \
     }                                                                     \
@@ -198,7 +198,7 @@ BINARY_COMP_HELPER(LessEquals, <=)
   do {                                                                  \
     using namespace ::c10::enforce_detail;                              \
     const EnforceFailMessage& CAFFE_ENFORCE_THAT_IMPL_r_ = (condition); \
-    if (CAFFE_ENFORCE_THAT_IMPL_r_.bad()) {                             \
+    if (C10_UNLIKELY(CAFFE_ENFORCE_THAT_IMPL_r_.bad())) {               \
       ::c10::ThrowEnforceNotMet(                                        \
           __FILE__,                                                     \
           __LINE__,                                                     \
@@ -213,7 +213,7 @@ BINARY_COMP_HELPER(LessEquals, <=)
     using namespace ::c10::enforce_detail;                             \
     const EnforceFailMessage& CAFFE_ENFORCE_THAT_IMPL_WITH_CALLER_r_ = \
         (condition);                                                   \
-    if (CAFFE_ENFORCE_THAT_IMPL_WITH_CALLER_r_.bad()) {                \
+    if (C10_UNLIKELY(CAFFE_ENFORCE_THAT_IMPL_WITH_CALLER_r_.bad())) {  \
       ::c10::ThrowEnforceNotMet(                                       \
           __FILE__,                                                    \
           __LINE__,                                                    \