offload/DeviceRTL/include/Mapping.h

   1 //===--------- Mapping.h - OpenMP device runtime mapping helpers -- 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 //
  10 //===----------------------------------------------------------------------===//
  11
  12 #ifndef OMPTARGET_MAPPING_H
  13 #define OMPTARGET_MAPPING_H
  14
  15 #include "DeviceTypes.h"
  16
  17 namespace ompx {
  18
  19 namespace mapping {
  20
  21 enum {
  22   DIM_X = 0,
  23   DIM_Y = 1,
  24   DIM_Z = 2,
  25 };
  26
  27 #pragma omp begin declare target device_type(nohost)
  28
  29 inline constexpr uint32_t MaxThreadsPerTeam = 1024;
  30
  31 #pragma omp end declare target
  32
  33 /// Initialize the mapping machinery.
  34 void init(bool IsSPMD);
  35
  36 /// Return true if the kernel is executed in SPMD mode.
  37 bool isSPMDMode();
  38
  39 /// Return true if the kernel is executed in generic mode.
  40 bool isGenericMode();
  41
  42 /// Return true if the executing thread is the main thread in generic mode.
  43 /// These functions will lookup state and it is required that that is OK for the
  44 /// thread and location. See also `isInitialThreadInLevel0` for a stateless
  45 /// alternative for certain situations, e.g. during initialization.
  46 bool isMainThreadInGenericMode();
  47 bool isMainThreadInGenericMode(bool IsSPMD);
  48
  49 /// Return true if this thread is the initial thread in parallel level 0.
  50 ///
  51 /// The thread for which this returns true should be used for single threaded
  52 /// initialization tasks. We pick a special thread to ensure there are no
  53 /// races between the initialization and the first read of initialized state.
  54 bool isInitialThreadInLevel0(bool IsSPMD);
  55
  56 /// Return true if the executing thread has the lowest Id of the active threads
  57 /// in the warp.
  58 bool isLeaderInWarp();
  59
  60 /// Return a mask describing all active threads in the warp.
  61 LaneMaskTy activemask();
  62
  63 /// Return a mask describing all threads with a smaller Id in the warp.
  64 LaneMaskTy lanemaskLT();
  65
  66 /// Return a mask describing all threads with a larget Id in the warp.
  67 LaneMaskTy lanemaskGT();
  68
  69 /// Return the thread Id in the warp, in [0, getWarpSize()).
  70 uint32_t getThreadIdInWarp();
  71
  72 /// Return the warp size, thus number of threads in the warp.
  73 uint32_t getWarpSize();
  74
  75 /// Return the warp id in the block, in [0, getNumberOfWarpsInBlock()]
  76 uint32_t getWarpIdInBlock();
  77
  78 /// Return the number of warps in the block.
  79 uint32_t getNumberOfWarpsInBlock();
  80
  81 /// Return the thread Id in the block, in [0, getNumberOfThreadsInBlock(Dim)).
  82 uint32_t getThreadIdInBlock(int32_t Dim = DIM_X);
  83
  84 /// Return the block size, thus number of threads in the block.
  85 uint32_t getNumberOfThreadsInBlock(int32_t Dim = DIM_X);
  86
  87 /// Return the block Id in the kernel, in [0, getNumberOfBlocksInKernel(Dim)).
  88 uint32_t getBlockIdInKernel(int32_t Dim = DIM_X);
  89
  90 /// Return the number of blocks in the kernel.
  91 uint32_t getNumberOfBlocksInKernel(int32_t Dim = DIM_X);
  92
  93 /// Return the kernel size, thus number of threads in the kernel.
  94 uint32_t getNumberOfThreadsInKernel();
  95
  96 /// Return the maximal number of threads in the block usable for a team (=
  97 /// parallel region).
  98 ///
  99 /// Note: The version taking \p IsSPMD mode explicitly can be used during the
 100 /// initialization of the target region, that is before `mapping::isSPMDMode()`
 101 /// can be called by any thread other than the main one.
 102 uint32_t getMaxTeamThreads();
 103 uint32_t getMaxTeamThreads(bool IsSPMD);
 104
 105 /// Return the number of processing elements on the device.
 106 uint32_t getNumberOfProcessorElements();
 107
 108 } // namespace mapping
 109
 110 } // namespace ompx
 111
 112 #endif