[llvm] [RISCV] Lower vector_splice on zvfhmin/zvfbfmin (PR #112579)

[Luke Lau via llvm-commits]

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@@ -86,6 +93,13 @@ define void @vector_splice() {
 ; SIZE-NEXT:  Cost Model: Found an estimated cost of 4 for instruction: %splice.nxv16i64 = call <vscale x 16 x i64> @llvm.vector.splice.nxv16i64(<vscale x 16 x i64> zeroinitializer, <vscale x 16 x i64> zeroinitializer, i32 -1)
 ; SIZE-NEXT:  Cost Model: Found an estimated cost of 8 for instruction: %splice.nxv32i64 = call <vscale x 32 x i64> @llvm.vector.splice.nxv32i64(<vscale x 32 x i64> zeroinitializer, <vscale x 32 x i64> zeroinitializer, i32 -1)
 ; SIZE-NEXT:  Cost Model: Found an estimated cost of 16 for instruction: %splice.nxv64i64 = call <vscale x 64 x i64> @llvm.vector.splice.nxv64i64(<vscale x 64 x i64> zeroinitializer, <vscale x 64 x i64> zeroinitializer, i32 -1)
+; SIZE-NEXT:  Cost Model: Invalid cost for instruction: %splice.nxv1bf16 = call <vscale x 1 x bfloat> @llvm.vector.splice.nxv1bf16(<vscale x 1 x bfloat> zeroinitializer, <vscale x 1 x bfloat> zeroinitializer, i32 -1)
+; SIZE-NEXT:  Cost Model: Invalid cost for instruction: %splice.nxv2bf16 = call <vscale x 2 x bfloat> @llvm.vector.splice.nxv2bf16(<vscale x 2 x bfloat> zeroinitializer, <vscale x 2 x bfloat> zeroinitializer, i32 -1)
+; SIZE-NEXT:  Cost Model: Invalid cost for instruction: %splice.nxv4bf16 = call <vscale x 4 x bfloat> @llvm.vector.splice.nxv4bf16(<vscale x 4 x bfloat> zeroinitializer, <vscale x 4 x bfloat> zeroinitializer, i32 -1)
+; SIZE-NEXT:  Cost Model: Invalid cost for instruction: %splice.nxv8bf16 = call <vscale x 8 x bfloat> @llvm.vector.splice.nxv8bf16(<vscale x 8 x bfloat> zeroinitializer, <vscale x 8 x bfloat> zeroinitializer, i32 -1)
+; SIZE-NEXT:  Cost Model: Invalid cost for instruction: %splice.nxv16bf16 = call <vscale x 16 x bfloat> @llvm.vector.splice.nxv16bf16(<vscale x 16 x bfloat> zeroinitializer, <vscale x 16 x bfloat> zeroinitializer, i32 -1)
+; SIZE-NEXT:  Cost Model: Invalid cost for instruction: %splice.nxv32bf16 = call <vscale x 32 x bfloat> @llvm.vector.splice.nxv32bf16(<vscale x 32 x bfloat> zeroinitializer, <vscale x 32 x bfloat> zeroinitializer, i32 -1)
+; SIZE-NEXT:  Cost Model: Invalid cost for instruction: %splice.nxv64bf16 = call <vscale x 64 x bfloat> @llvm.vector.splice.nxv64bf16(<vscale x 64 x bfloat> zeroinitializer, <vscale x 64 x bfloat> zeroinitializer, i32 -1)
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lukel97 wrote:

Not sure why the size is returning an invalid cost but the throughput is OK. Will look at it in another PR

https://github.com/llvm/llvm-project/pull/112579