[llvm] [AMDGPU][True16][CodeGen] stop emitting spgr_lo16 from isel (PR #144819)

[Brox Chen via llvm-commits]

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@@ -1471,17 +1471,34 @@ def : GCNPat<
 >;
 
 def : GCNPat<
-  (i64 (anyext i16:$src)),
+  (i64 (UniformUnaryFrag<anyext> i16:$src)),
+  (REG_SEQUENCE VReg_64,
+     (i32 (COPY $src)), sub0,
+     (V_MOV_B32_e32 (i32 0)), sub1)
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broxigarchen wrote:

It seems using SReg_64 here introduces some related changes in the test. I would rather not do it in this patch

https://github.com/llvm/llvm-project/pull/144819