[llvm] [NVPTX] Optimize v2x16 BUILD_VECTORs to PRMT (PR #116675)

[Fraser Cormack via llvm-commits]

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@@ -159,8 +159,8 @@ define <2 x bfloat> @test_faddx2(<2 x bfloat> %a, <2 x bfloat> %b) #0 {
 ; SM70-LABEL: test_faddx2(
 ; SM70:       {
 ; SM70-NEXT:    .reg .pred %p<3>;
-; SM70-NEXT:    .reg .b16 %rs<13>;
-; SM70-NEXT:    .reg .b32 %r<24>;
+; SM70-NEXT:    .reg .b16 %rs<9>;
+; SM70-NEXT:    .reg .b32 %r<25>;
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frasercrmck wrote:

Any idea why this shows an increase in `%r` registers when it seems as though there are just as many as before?

https://github.com/llvm/llvm-project/pull/116675