[Openmp-commits] [openmp] cf6ae06 - [OpenMP] Remove declaration and usage of __AMDGCN_WAVEFRONT_SIZE (#143761)

[via Openmp-commits]

Author: nicebert
Date: 2025-06-13T10:46:36-04:00
New Revision: cf6ae065a042aae6324b28e99628c40bc53be0b7

URL: https://github.com/llvm/llvm-project/commit/cf6ae065a042aae6324b28e99628c40bc53be0b7
DIFF: https://github.com/llvm/llvm-project/commit/cf6ae065a042aae6324b28e99628c40bc53be0b7.diff

LOG: [OpenMP] Remove declaration and usage of __AMDGCN_WAVEFRONT_SIZE (#143761)

Removes usage of __AMDGCN_WAVEFRONT_SIZE as compile time constant.

---------

Co-authored-by: Shilei Tian <i at tianshilei.me>

Added: 
    

Modified: 
    openmp/runtime/src/include/ompx.h.var

Removed: 
    


################################################################################
diff  --git a/openmp/runtime/src/include/ompx.h.var b/openmp/runtime/src/include/ompx.h.var
index 623f0b9c315bd..6884745f4240c 100644
--- a/openmp/runtime/src/include/ompx.h.var
+++ b/openmp/runtime/src/include/ompx.h.var
@@ -9,13 +9,21 @@
 #ifndef __OMPX_H
 #define __OMPX_H
 
-#ifdef __AMDGCN_WAVEFRONT_SIZE
-#define __WARP_SIZE __AMDGCN_WAVEFRONT_SIZE
-#else
-#define __WARP_SIZE 32
+#if (defined(__NVPTX__) || defined(__AMDGPU__))
+#include <gpuintrin.h>
+#define __OMPX_TARGET_IS_GPU
 #endif
 
 typedef unsigned long uint64_t;
+typedef unsigned int uint32_t;
+
+static inline uint32_t __warpSize(void) {
+#ifdef __OMPX_TARGET_IS_GPU
+  return __gpu_num_lanes();
+#else
+  __builtin_trap();
+#endif
+}
 
 #ifdef __cplusplus
 extern "C" {
@@ -212,7 +220,7 @@ static inline uint64_t ballot_sync(uint64_t mask, int pred) {
 ///{
 #define _TGT_KERNEL_LANGUAGE_SHFL_DOWN_SYNC(TYPE, TY)                          \
   static inline TYPE shfl_down_sync(uint64_t mask, TYPE var, unsigned delta,   \
-                                    int width = __WARP_SIZE) {                 \
+                                    int width = __warpSize()) {                \
     return ompx_shfl_down_sync_##TY(mask, var, delta, width);                  \
   }