[llvm] [AMDGPU][True16][CodeGen] update isel pattern with vgpr16 for 16 bit types (PR #154875)

[Brox Chen via llvm-commits]

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@@ -43,13 +43,22 @@ define amdgpu_ps i16 @s_copysign_f16(half inreg %mag, half inreg %sign) {
 ; GFX9-NEXT:    v_readfirstlane_b32 s0, v0
 ; GFX9-NEXT:    ; return to shader part epilog
 ;
-; GFX11-LABEL: s_copysign_f16:
-; GFX11:       ; %bb.0:
-; GFX11-NEXT:    v_mov_b32_e32 v0, s1
-; GFX11-NEXT:    s_delay_alu instid0(VALU_DEP_1) | instskip(NEXT) | instid1(VALU_DEP_1)
-; GFX11-NEXT:    v_bfi_b32 v0, 0x7fff, s0, v0
-; GFX11-NEXT:    v_readfirstlane_b32 s0, v0
-; GFX11-NEXT:    ; return to shader part epilog
+; GFX11-TRUE16-LABEL: s_copysign_f16:
+; GFX11-TRUE16:       ; %bb.0:
+; GFX11-TRUE16-NEXT:    v_mov_b16_e32 v0.l, s1
+; GFX11-TRUE16-NEXT:    v_mov_b16_e32 v1.l, s0
+; GFX11-TRUE16-NEXT:    s_delay_alu instid0(VALU_DEP_1) | instskip(NEXT) | instid1(VALU_DEP_1)
+; GFX11-TRUE16-NEXT:    v_bfi_b32 v0, 0x7fff, v1, v0
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broxigarchen wrote:

Will open another patch for this

https://github.com/llvm/llvm-project/pull/154875