[llvm] stop emitting direct copy from intermediate result to out reg (PR #135326)

[Pankaj Dwivedi via llvm-commits]

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@@ -1,21 +1,91 @@
-; NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 5
-; RUN: llc < %s -mtriple=amdgcn -mcpu=gfx1100 -verify-machineinstrs -stop-after=finalize-isel | FileCheck %s -check-prefixes=GFX11
-
-define amdgpu_ps i32 @s_copysign_f32_bf16(float inreg %mag, bfloat inreg %sign.bf16) {
-  ; GFX11-LABEL: name: s_copysign_f32_bf16
-  ; GFX11: bb.0 (%ir-block.0):
-  ; GFX11-NEXT:   liveins: $sgpr0, $sgpr1
-  ; GFX11-NEXT: {{  $}}
-  ; GFX11-NEXT:   [[COPY:%[0-9]+]]:sgpr_32 = COPY $sgpr1
-  ; GFX11-NEXT:   [[COPY1:%[0-9]+]]:sgpr_32 = COPY $sgpr0
-  ; GFX11-NEXT:   [[V_LSHLREV_B32_e64_:%[0-9]+]]:vgpr_32 = V_LSHLREV_B32_e64 16, [[COPY]], implicit $exec
-  ; GFX11-NEXT:   [[S_MOV_B32_:%[0-9]+]]:sreg_32 = S_MOV_B32 2147483647
-  ; GFX11-NEXT:   [[V_BFI_B32_e64_:%[0-9]+]]:vgpr_32 = V_BFI_B32_e64 killed [[S_MOV_B32_]], [[COPY1]], killed [[V_LSHLREV_B32_e64_]], implicit $exec
-  ; GFX11-NEXT:   [[V_READFIRSTLANE_B32_:%[0-9]+]]:sreg_32_xm0 = V_READFIRSTLANE_B32 killed [[V_BFI_B32_e64_]], implicit $exec
-  ; GFX11-NEXT:   $sgpr0 = COPY [[V_READFIRSTLANE_B32_]]
-  ; GFX11-NEXT:   SI_RETURN_TO_EPILOG $sgpr0
-  %sign = fpext bfloat %sign.bf16 to float
-  %op = call float @llvm.copysign.f32(float %mag, float %sign)
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc < %s -mtriple=amdgcn -mcpu=gfx1100 | FileCheck %s -check-prefixes=GFX11
+
+define amdgpu_ps i32 @s_copysign_uniform(float inreg %x, float inreg %y) {
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PankajDwivedi-25 wrote:

in case of fpxet, it returns in vgpr.

https://github.com/llvm/llvm-project/pull/135326