[llvm] [AMDGPU] New intrinsic llvm.amdgcn.pops.exiting.wave.id (PR #89612)

[via llvm-commits]

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@@ -0,0 +1,34 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 4
+; RUN: llc -global-isel=0 -mtriple=amdgcn -mcpu=gfx900 < %s | FileCheck %s -check-prefix=SDAG
+; RUN: llc -global-isel=1 -mtriple=amdgcn -mcpu=gfx900 < %s | FileCheck %s -check-prefix=GFX9-GISEL
+; RUN: llc -global-isel=0 -mtriple=amdgcn -mcpu=gfx1010 < %s | FileCheck %s -check-prefix=SDAG
+; RUN: llc -global-isel=1 -mtriple=amdgcn -mcpu=gfx1010 < %s | FileCheck %s -check-prefix=GFX10-GISEL
+
+define amdgpu_ps void @test(ptr addrspace(1) inreg %ptr) {
+; SDAG-LABEL: test:
+; SDAG:       ; %bb.0:
+; SDAG-NEXT:    s_mov_b32 s2, src_pops_exiting_wave_id
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Triang3l wrote:

Another possible, but disgustingly dirty approach would be to expose it not as a load, but rather directly as an integer addition to an operand 🙃 But that'd definitely add some excessive responsibilities to it, especially since there are other ways the wave ID wraparound can be handled such as comparisons, and I don't know how unfriendly to the rest of the architecture that would be.

https://github.com/llvm/llvm-project/pull/89612