[llvm] [SDAG] Fix fmaximum legalization errors (PR #142170)

[Alex MacLean via llvm-commits]

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@@ -1476,7 +1476,7 @@ define <2 x bfloat> @test_maximum_v2(<2 x bfloat> %a, <2 x bfloat> %b) {
 ; SM70-LABEL: test_maximum_v2(
 ; SM70:       {
 ; SM70-NEXT:    .reg .pred %p<11>;
-; SM70-NEXT:    .reg .b16 %rs<15>;
+; SM70-NEXT:    .reg .b16 %rs<19>;
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AlexMaclean wrote:

These numbers can be a bit misleading since there are sometimes holes in the register range. That is what seems to be happening here. NVPTX changes look like improvements or no-ops to me fwiw.

https://github.com/llvm/llvm-project/pull/142170