[llvm] [AMDGPU] Support true16 spill restore with sram-ecc (PR #165320)

[Joe Nash via llvm-commits]

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@@ -341,6 +519,47 @@ define void @spill_2xi16_from_v2i16_one_free_reg() {
 ; GCN-FAKE16-NEXT:    scratch_store_b16 off, v0, s32 dlc
 ; GCN-FAKE16-NEXT:    s_waitcnt_vscnt null, 0x0
 ; GCN-FAKE16-NEXT:    s_setpc_b64 s[30:31]
+;
+; GFX1250-TRUE16-LABEL: spill_2xi16_from_v2i16_one_free_reg:
+; GFX1250-TRUE16:       ; %bb.0: ; %entry
+; GFX1250-TRUE16-NEXT:    s_wait_loadcnt_dscnt 0x0
+; GFX1250-TRUE16-NEXT:    s_wait_kmcnt 0x0
+; GFX1250-TRUE16-NEXT:    scratch_load_u16 v7, off, s32 offset:2 scope:SCOPE_SYS
+; GFX1250-TRUE16-NEXT:    s_wait_loadcnt 0x0
+; GFX1250-TRUE16-NEXT:    scratch_load_u16 v0, off, s32 scope:SCOPE_SYS
+; GFX1250-TRUE16-NEXT:    s_wait_loadcnt 0x0
+; GFX1250-TRUE16-NEXT:    scratch_store_b32 off, v0, s32 offset:8 ; 4-byte Folded Spill
+; GFX1250-TRUE16-NEXT:    s_wait_xcnt 0x0
+; GFX1250-TRUE16-NEXT:    ;;#ASMSTART
+; GFX1250-TRUE16-NEXT:    ;;#ASMEND
+; GFX1250-TRUE16-NEXT:    v_mov_b16_e32 v0.l, v7.l
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Sisyph wrote:

A little unfortunate we can't fold this mov away since it gets inserted late. 

https://github.com/llvm/llvm-project/pull/165320