[llvm] [AMDGPU] Sign extend simm16 in setreg intrinsic (PR #77997)

[Matt Arsenault via llvm-commits]

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@@ -1160,6 +1158,9 @@ def S_SETREG_IMM32_B32_mode : S_SETREG_IMM32_B32_Pseudo {
 
 } // End Defs = [MODE], Uses = [MODE]
 
+def : GCNPat<(int_amdgcn_s_setreg (i32 timm:$simm16), i32:$sdst),
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arsenm wrote:

Could define an SDNodeXForm for TimmLeaf and avoid splitting out the pattern from the instruction definition 

https://github.com/llvm/llvm-project/pull/77997