[llvm] AMDGPU/GlobalISel: Fix inst-selection of ballot (PR #109986)

[Petar Avramovic via llvm-commits]

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@@ -132,7 +132,8 @@ define amdgpu_ps void @struct_ptr_buffer_store_format_f32__sgpr_val__vgpr_rsrc__
   ; CHECK-NEXT:   [[V_READFIRSTLANE_B32_4:%[0-9]+]]:sreg_32 = V_READFIRSTLANE_B32 [[COPY7]], implicit $exec
   ; CHECK-NEXT:   [[V_CMP_EQ_U32_e64_:%[0-9]+]]:sreg_64_xexec = V_CMP_EQ_U32_e64 [[V_READFIRSTLANE_B32_4]], [[COPY7]], implicit $exec
   ; CHECK-NEXT:   [[S_AND_B64_1:%[0-9]+]]:sreg_64_xexec = S_AND_B64 [[S_AND_B64_]], [[V_CMP_EQ_U32_e64_]], implicit-def dead $scc
-  ; CHECK-NEXT:   [[S_AND_SAVEEXEC_B64_:%[0-9]+]]:sreg_64_xexec = S_AND_SAVEEXEC_B64 killed [[S_AND_B64_1]], implicit-def $exec, implicit-def $scc, implicit $exec
+  ; CHECK-NEXT:   [[S_AND_B64_2:%[0-9]+]]:sreg_64_xexec = S_AND_B64 [[S_AND_B64_1]], $exec, implicit-def dead $scc
+  ; CHECK-NEXT:   [[S_AND_SAVEEXEC_B64_:%[0-9]+]]:sreg_64_xexec = S_AND_SAVEEXEC_B64 killed [[S_AND_B64_2]], implicit-def $exec, implicit-def $scc, implicit $exec
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petar-avramovic wrote:

Will rewrite the patch next week, need to look through AND and OR and see if some of the values was made with same exec(going back to your suggestion to just check for same block). I was thinking to simply do 'copy' instead of sinking compare or 'AND with exec'

https://github.com/llvm/llvm-project/pull/109986