libc/src/__support/GPU/utils.h

   1 //===---------------- Implementation of GPU utils ---------------*- C++ -*-===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #ifndef LLVM_LIBC_SRC___SUPPORT_GPU_UTIL_H
  10 #define LLVM_LIBC_SRC___SUPPORT_GPU_UTIL_H
  11
  12 #include "src/__support/macros/properties/architectures.h"
  13
  14 #if defined(LIBC_TARGET_ARCH_IS_AMDGPU)
  15 #include "amdgpu/utils.h"
  16 #elif defined(LIBC_TARGET_ARCH_IS_NVPTX)
  17 #include "nvptx/utils.h"
  18 #else
  19 #include "generic/utils.h"
  20 #endif
  21
  22 namespace LIBC_NAMESPACE {
  23 namespace gpu {
  24 /// Get the first active thread inside the lane.
  25 LIBC_INLINE uint64_t get_first_lane_id(uint64_t lane_mask) {
  26   return __builtin_ffsl(lane_mask) - 1;
  27 }
  28
  29 /// Conditional that is only true for a single thread in a lane.
  30 LIBC_INLINE bool is_first_lane(uint64_t lane_mask) {
  31   return gpu::get_lane_id() == get_first_lane_id(lane_mask);
  32 }
  33
  34 } // namespace gpu
  35 } // namespace LIBC_NAMESPACE
  36
  37 #endif // LLVM_LIBC_SRC___SUPPORT_OSUTIL_IO_H