[Openmp-commits] [PATCH] D125467: [openmp] Fix strict aliasing issue in cmpxchg routine

[serge via Phabricator via Openmp-commits]

serge-sans-paille updated this revision to Diff 428928.

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D125467/new/

https://reviews.llvm.org/D125467

Files:
  openmp/runtime/src/kmp_os.h


Index: openmp/runtime/src/kmp_os.h
===================================================================
--- openmp/runtime/src/kmp_os.h
+++ openmp/runtime/src/kmp_os.h
@@ -17,6 +17,7 @@
 #include <atomic>
 #include <stdarg.h>
 #include <stdlib.h>
+#include <string.h>
 
 #define KMP_FTN_PLAIN 1
 #define KMP_FTN_APPEND 2
@@ -864,15 +865,25 @@
   __sync_lock_test_and_set((volatile kmp_uint64 *)(p), (kmp_uint64)(v))
 
 inline kmp_real32 KMP_XCHG_REAL32(volatile kmp_real32 *p, kmp_real32 v) {
-  kmp_int32 tmp =
-      __sync_lock_test_and_set((volatile kmp_uint32 *)(p), *(kmp_uint32 *)&v);
-  return *(kmp_real32 *)&tmp;
+  volatile kmp_uint32 *up;
+  kmp_uint32 uv;
+  memcpy(&up, &p, sizeof(up));
+  memcpy(&uv, &v, sizeof(uv));
+  kmp_int32 tmp = __sync_lock_test_and_set(up, uv);
+  kmp_real32 ftmp;
+  memcpy(&ftmp, &tmp, sizeof(tmp));
+  return ftmp;
 }
 
 inline kmp_real64 KMP_XCHG_REAL64(volatile kmp_real64 *p, kmp_real64 v) {
-  kmp_int64 tmp =
-      __sync_lock_test_and_set((volatile kmp_uint64 *)(p), *(kmp_uint64 *)&v);
-  return *(kmp_real64 *)&tmp;
+  volatile kmp_uint64 *up;
+  kmp_uint64 uv;
+  memcpy(&up, &p, sizeof(up));
+  memcpy(&uv, &v, sizeof(uv));
+  kmp_int64 tmp = __sync_lock_test_and_set(up, uv);
+  kmp_real64 dtmp;
+  memcpy(&dtmp, &tmp, sizeof(tmp));
+  return dtmp;
 }
 
 #else


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