[llvm] [openmp] [OpenMPOpt] Ask the runtime how many of a block's threads can be workers (PR #221450)

[Larry Meadows via llvm-commits]

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@@ -175,6 +175,12 @@ extern "C" {
 [[gnu::noinline]] uint32_t __kmpc_get_warp_size() {
   return mapping::getWarpSize();
 }
+
+// The mode is a parameter because callers reach this before the barrier that
+// would make the shared IsSPMDMode visible to them.
+[[gnu::noinline]] uint32_t __kmpc_get_max_team_threads(int32_t IsSPMD) {
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lfmeadow wrote:

OpenMPOpt emits calls to these when it builds the custom state machine, so they have to survive as named symbols: `__kmpc_get_hardware_thread_id_in_block`, `__kmpc_get_hardware_num_threads_in_block`, `__kmpc_get_warp_size`, and now `__kmpc_get_max_team_threads`.

https://github.com/llvm/llvm-project/pull/221450