[llvm-branch-commits] [llvm] [AMDGPU] Allow 16-bit imm folding in real true16 (PR #173318)

[Brox Chen via llvm-branch-commits]

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@@ -19,27 +19,16 @@ define amdgpu_kernel void @store_inline_imm_neg_0.0_i16(ptr addrspace(1) %out) {
 ; GFX10-NEXT:    s_waitcnt_vscnt null, 0x0 ; encoding: [0x00,0x00,0xfd,0xbb]
 ; GFX10-NEXT:    s_endpgm ; encoding: [0x00,0x00,0x81,0xbf]
 ;
-; GFX11-TRUE16-LABEL: store_inline_imm_neg_0.0_i16:
-; GFX11-TRUE16:       ; %bb.0:
-; GFX11-TRUE16-NEXT:    s_load_b64 s[0:1], s[4:5], 0x0 ; encoding: [0x02,0x00,0x04,0xf4,0x00,0x00,0x00,0xf8]
-; GFX11-TRUE16-NEXT:    v_mov_b16_e32 v0.l, 0x8000 ; encoding: [0xff,0x38,0x00,0x7e,0x00,0x80,0xff,0xff]
-; GFX11-TRUE16-NEXT:    s_mov_b32 s3, 0x31016000 ; encoding: [0xff,0x00,0x83,0xbe,0x00,0x60,0x01,0x31]
-; GFX11-TRUE16-NEXT:    s_mov_b32 s2, -1 ; encoding: [0xc1,0x00,0x82,0xbe]
-; GFX11-TRUE16-NEXT:    s_waitcnt lgkmcnt(0) ; encoding: [0x07,0xfc,0x89,0xbf]
-; GFX11-TRUE16-NEXT:    buffer_store_b16 v0, off, s[0:3], 0 dlc ; encoding: [0x00,0x20,0x64,0xe0,0x00,0x00,0x00,0x80]
-; GFX11-TRUE16-NEXT:    s_waitcnt_vscnt null, 0x0 ; encoding: [0x00,0x00,0x7c,0xbc]
-; GFX11-TRUE16-NEXT:    s_endpgm ; encoding: [0x00,0x00,0xb0,0xbf]
-;
-; GFX11-FAKE16-LABEL: store_inline_imm_neg_0.0_i16:
-; GFX11-FAKE16:       ; %bb.0:
-; GFX11-FAKE16-NEXT:    s_load_b64 s[0:1], s[4:5], 0x0 ; encoding: [0x02,0x00,0x04,0xf4,0x00,0x00,0x00,0xf8]
-; GFX11-FAKE16-NEXT:    v_mov_b32_e32 v0, 0xffff8000 ; encoding: [0xff,0x02,0x00,0x7e,0x00,0x80,0xff,0xff]
-; GFX11-FAKE16-NEXT:    s_mov_b32 s3, 0x31016000 ; encoding: [0xff,0x00,0x83,0xbe,0x00,0x60,0x01,0x31]
-; GFX11-FAKE16-NEXT:    s_mov_b32 s2, -1 ; encoding: [0xc1,0x00,0x82,0xbe]
-; GFX11-FAKE16-NEXT:    s_waitcnt lgkmcnt(0) ; encoding: [0x07,0xfc,0x89,0xbf]
-; GFX11-FAKE16-NEXT:    buffer_store_b16 v0, off, s[0:3], 0 dlc ; encoding: [0x00,0x20,0x64,0xe0,0x00,0x00,0x00,0x80]
-; GFX11-FAKE16-NEXT:    s_waitcnt_vscnt null, 0x0 ; encoding: [0x00,0x00,0x7c,0xbc]
-; GFX11-FAKE16-NEXT:    s_endpgm ; encoding: [0x00,0x00,0xb0,0xbf]
+; GFX11-LABEL: store_inline_imm_neg_0.0_i16:
+; GFX11:       ; %bb.0:
+; GFX11-NEXT:    s_load_b64 s[0:1], s[4:5], 0x0 ; encoding: [0x02,0x00,0x04,0xf4,0x00,0x00,0x00,0xf8]
+; GFX11-NEXT:    v_mov_b32_e32 v0, 0xffff8000 ; encoding: [0xff,0x02,0x00,0x7e,0x00,0x80,0xff,0xff]
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broxigarchen wrote:

>From my understanding this patch is something we need for true16. However I am not quite understand why we have this 0xffff0000 folded in to v0 here. It seems we don't have this prior to this patch

https://github.com/llvm/llvm-project/pull/173318