[llvm] AMDGPU][True16][CodeGen] fold clamp update for true16 (PR #128919)

[Joe Nash via llvm-commits]

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@@ -0,0 +1,33 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py
+# RUN: llc -march=amdgcn -mcpu=gfx1100 -run-pass si-fold-operands -mattr="+wavefrontsize32",+real-true16 -verify-machineinstrs -o - %s | FileCheck %s
+
+---
+name:            fold_16bit_madmix_clamp
+tracksRegLiveness: true
+registers:
+body:             |
+  bb.0.entry:
+    liveins: $vgpr0, $vgpr1, $vgpr2
+    ; CHECK-LABEL: name: fold_16bit_madmix_clamp
+    ; CHECK: liveins: $vgpr0, $vgpr1, $vgpr2
+    ; CHECK-NEXT: {{  $}}
+    ; CHECK-NEXT: [[COPY:%[0-9]+]]:vgpr_32 = COPY $vgpr2
+    ; CHECK-NEXT: [[COPY1:%[0-9]+]]:vgpr_32 = COPY $vgpr1
+    ; CHECK-NEXT: [[COPY2:%[0-9]+]]:vgpr_32 = COPY $vgpr0
+    ; CHECK-NEXT: [[DEF:%[0-9]+]]:sreg_32 = IMPLICIT_DEF
+    ; CHECK-NEXT: [[COPY3:%[0-9]+]]:vgpr_32 = COPY [[DEF]]
+    ; CHECK-NEXT: [[V_FMA_MIXLO_F16_:%[0-9]+]]:vgpr_32 = nofpexcept V_FMA_MIXLO_F16 8, [[COPY2]], 8, [[COPY1]], 0, [[COPY]], 1, [[COPY3]], 0, 0, implicit $mode, implicit $exec
+    ; CHECK-NEXT: [[COPY4:%[0-9]+]]:vgpr_16 = COPY [[V_FMA_MIXLO_F16_]]
+    ; CHECK-NEXT: $vgpr0 = COPY [[COPY4]]
+    ; CHECK-NEXT: S_ENDPGM 0, implicit $vgpr0
+    %10:vgpr_32 = COPY $vgpr2
+    %9:vgpr_32 = COPY $vgpr1
+    %8:vgpr_32 = COPY $vgpr0
+    %12:sreg_32 = IMPLICIT_DEF
+    %13:vgpr_32 = COPY %12:sreg_32
+    %11:vgpr_32 = nofpexcept V_FMA_MIXLO_F16 8, %8:vgpr_32, 8, %9:vgpr_32, 0, %10:vgpr_32, 0, %13:vgpr_32, 0, 0, implicit $mode, implicit $exec
+    %15:vgpr_16 = COPY %11:vgpr_32
+    %14:vgpr_16 = nofpexcept V_MAX_F16_t16_e64 0, %15:vgpr_16, 0, %15:vgpr_16, -1, 0, 0, implicit $mode, implicit $exec
+    $vgpr0 = COPY %14:vgpr_16
+    S_ENDPGM 0, implicit $vgpr0
+...
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Sisyph wrote:

I don't understand if you guys are saying the code before this patch is broken, or after this patch. In either case, we should add the tests and make changes to the code as necessary. If it's before, we should fix it, but it's not urgent because users aren't complaining. If it's broken after this patch, it should still be fixed, in whatever order is most convenient with upstreaming the other true16 patches.

https://github.com/llvm/llvm-project/pull/128919