[llvm] [AMDGPU][True16][CodeGen] true16 codegen for bswap (PR #122849)

[Matt Arsenault via llvm-commits]

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@@ -3039,6 +3041,19 @@ def : GCNPat <
   (i32 (zext (bswap i16:$a))),
   (V_PERM_B32_e64  (i32 0), VSrc_b32:$a, (S_MOV_B32 (i32 0x0c0c0001)))
 >;
+}
+
+let True16Predicate = UseRealTrue16Insts in {
+def : GCNPat <
+  (i16 (bswap i16:$a)),
+  (EXTRACT_SUBREG (V_PERM_B32_e64  (i32 0), (COPY VGPR_16:$a), (S_MOV_B32 (i32 0x0c0c0001))), lo16)
+>;
+
+def : GCNPat <
+  (i32 (zext (bswap i16:$a))),
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arsenm wrote:

should this handle zext or any ext 

https://github.com/llvm/llvm-project/pull/122849