[llvm] [RISCV][GISEL] instruction-select for G_SPLAT_VECTOR (PR #111193)

[Craig Topper via llvm-commits]

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@@ -67,7 +67,428 @@ define <vscale x 64 x i1> @splat_zero_nxv64i1() {
   ret <vscale x 64 x i1> zeroinitializer
 }
 
+define <vscale x 1 x i8> @splat_zero_nxv1i8() {
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topperc wrote:

Which is failing in my local test because the indices weren't CSEd

  %4:_(s64) = G_CONSTANT i64 0                                                                                   
  %2:_(<vscale x 2 x s32>) = G_INSERT_VECTOR_ELT %3:_, %0:_(s32), %4:_(s64)                                      
  %5:_(s64) = G_CONSTANT i64 0                                                                                   
  %6:_(s32) = G_EXTRACT_VECTOR_ELT %2:_(<vscale x 2 x s32>), %5:_(s64)  

https://github.com/llvm/llvm-project/pull/111193