[llvm] [RISCV][TTI] Check type-legalization for both src and dst when calculating cost of cast instructions. (PR #143843)

[Craig Topper via llvm-commits]

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@@ -288,8 +288,8 @@ define void @sext() {
 ; RV32-NEXT:  Cost Model: Found an estimated cost of 35 for instruction: %nxv64i8_nxv64i32 = sext <vscale x 64 x i8> undef to <vscale x 64 x i32>
 ; RV32-NEXT:  Cost Model: Invalid cost for instruction: %nxv64i8_nxv64i64 = sext <vscale x 64 x i8> undef to <vscale x 64 x i64>
 ; RV32-NEXT:  Cost Model: Found an estimated cost of 34 for instruction: %nxv64i16_nxv64i32 = sext <vscale x 64 x i16> undef to <vscale x 64 x i32>
-; RV32-NEXT:  Cost Model: Found an estimated cost of 71 for instruction: %nxv64i16_nxv64i64 = sext <vscale x 64 x i16> undef to <vscale x 64 x i64>
-; RV32-NEXT:  Cost Model: Found an estimated cost of 69 for instruction: %nxv64i32_nxv64i64 = sext <vscale x 64 x i32> undef to <vscale x 64 x i64>
+; RV32-NEXT:  Cost Model: Invalid cost for instruction: %nxv64i16_nxv64i64 = sext <vscale x 64 x i16> undef to <vscale x 64 x i64>
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topperc wrote:

Yeah it looks like a bug further down in getTypeConversion.

https://github.com/llvm/llvm-project/pull/143843