[llvm] [AMDGPU] Detect kills in register sets when trying to form V_CMPX instructions. (PR #68293)

[Carl Ritson via llvm-commits]

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@@ -0,0 +1,39 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 3
+# RUN: llc -march=amdgcn -mcpu=gfx1100 -run-pass=si-optimize-exec-masking -verify-machineinstrs %s -o - | FileCheck -check-prefix=GFX1100 %s
+
+---
+
+name: vcmp_saveexec_to_vcmpx_set_kill
+tracksRegLiveness: true
+body: |
+  bb.0:
+    liveins: $sgpr43, $sgpr44, $sgpr45, $sgpr55, $sgpr62, $sgpr63, $sgpr64, $sgpr65, $sgpr66, $sgpr67, $vgpr40, $vgpr41, $vgpr76, $vgpr77, $vgpr78, $vgpr95, $vgpr109, $vgpr110, $vgpr111, $sgpr48_sgpr49_sgpr50_sgpr51:0x000000000000000C, $sgpr52_sgpr53_sgpr54_sgpr55:0x0000000000000003, $sgpr34_sgpr35, $sgpr36_sgpr37, $sgpr38_sgpr39, $sgpr40_sgpr41, $sgpr56_sgpr57, $sgpr58_sgpr59, $sgpr60_sgpr61, $vgpr92_vgpr93_vgpr94_vgpr95:0x000000000000003F, $vgpr104_vgpr105_vgpr106_vgpr107:0x000000000000003F, $vgpr46_vgpr47:0x000000000000000F, $vgpr60_vgpr61:0x000000000000000F, $vgpr62_vgpr63:0x000000000000000C, $vgpr72_vgpr73:0x000000000000000F, $vgpr74_vgpr75:0x000000000000000F, $vgpr88_vgpr89:0x000000000000000C, $vgpr90_vgpr91:0x0000000000000003, $vgpr124_vgpr125:0x000000000000000F, $vgpr126_vgpr127:0x000000000000000F
+
+    ; GFX1100-LABEL: name: vcmp_saveexec_to_vcmpx_set_kill
+    ; GFX1100: liveins: $sgpr43, $sgpr44, $sgpr45, $sgpr55, $sgpr62, $sgpr63, $sgpr64, $sgpr65, $sgpr66, $sgpr67, $vgpr40, $vgpr41, $vgpr76, $vgpr77, $vgpr78, $vgpr95, $vgpr109, $vgpr110, $vgpr111, $sgpr48_sgpr49_sgpr50_sgpr51:0x000000000000000C, $sgpr52_sgpr53_sgpr54_sgpr55:0x0000000000000003, $sgpr34_sgpr35, $sgpr36_sgpr37, $sgpr38_sgpr39, $sgpr40_sgpr41, $sgpr56_sgpr57, $sgpr58_sgpr59, $sgpr60_sgpr61, $vgpr92_vgpr93_vgpr94_vgpr95:0x000000000000003F, $vgpr104_vgpr105_vgpr106_vgpr107:0x000000000000003F, $vgpr46_vgpr47:0x000000000000000F, $vgpr60_vgpr61:0x000000000000000F, $vgpr62_vgpr63:0x000000000000000C, $vgpr72_vgpr73:0x000000000000000F, $vgpr74_vgpr75:0x000000000000000F, $vgpr88_vgpr89:0x000000000000000C, $vgpr90_vgpr91:0x0000000000000003, $vgpr124_vgpr125:0x000000000000000F, $vgpr126_vgpr127:0x000000000000000F
+    ; GFX1100-NEXT: {{  $}}
+    ; GFX1100-NEXT: renamable $vgpr0 = V_AND_B32_e32 128, $vgpr90, implicit $exec
+    ; GFX1100-NEXT: renamable $vgpr1 = V_AND_B32_e32 128, $vgpr89, implicit $exec
+    ; GFX1100-NEXT: renamable $sgpr4 = V_CMP_NE_U32_e64 0, $vgpr0, implicit $exec
+    ; GFX1100-NEXT: renamable $sgpr0 = S_MOV_B32 0
+    ; GFX1100-NEXT: renamable $sgpr1 = COPY renamable $sgpr0
+    ; GFX1100-NEXT: renamable $sgpr2 = COPY renamable $sgpr0
+    ; GFX1100-NEXT: renamable $sgpr3 = COPY renamable $sgpr0
+    ; GFX1100-NEXT: BUFFER_STORE_DWORDX2_OFFSET_exact $vgpr0_vgpr1, killed $sgpr0_sgpr1_sgpr2_sgpr3, 0, 344, 1, 0, implicit $exec :: (dereferenceable store (s64), align 1, addrspace 8)
+    ; GFX1100-NEXT: renamable $sgpr68 = COPY renamable $sgpr66
+    ; GFX1100-NEXT: $sgpr5 = S_MOV_B32 $exec_lo
+    ; GFX1100-NEXT: V_CMPX_EQ_U32_nosdst_e64 $vgpr0, 0, implicit-def $exec, implicit $exec
+    renamable $vgpr0 = V_AND_B32_e32 128, $vgpr90, implicit $exec
+    renamable $vgpr1 = V_AND_B32_e32 128, $vgpr89, implicit $exec
+    renamable $vcc_lo = V_CMP_EQ_U32_e64 $vgpr0, 0, implicit $exec
+    renamable $sgpr4 = V_CMP_NE_U32_e64 0, killed $vgpr0, implicit $exec
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perlfu wrote:

Surely it is illegal to kill vgpr0 here and then use it in the BUFFER_STORE?

https://github.com/llvm/llvm-project/pull/68293