[llvm] [BasicTTI] Use getTypeLegalizationCost to generalize vector cast cost. (PR #107303)

[Philip Reames via llvm-commits]

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@@ -559,22 +559,22 @@ define i32 @casts() {
 ; CHECK-MVE-RECIP-NEXT:  Cost Model: Found an estimated cost of 4 for instruction: %r87hf = fpext <4 x half> undef to <4 x float>
 ; CHECK-MVE-RECIP-NEXT:  Cost Model: Found an estimated cost of 8 for instruction: %r88hf = fpext <8 x half> undef to <8 x float>
 ; CHECK-MVE-RECIP-NEXT:  Cost Model: Found an estimated cost of 16 for instruction: %r89hf = fpext <16 x half> undef to <16 x float>
-; CHECK-MVE-RECIP-NEXT:  Cost Model: Found an estimated cost of 36 for instruction: %r90 = fptoui <2 x float> undef to <2 x i1>
-; CHECK-MVE-RECIP-NEXT:  Cost Model: Found an estimated cost of 36 for instruction: %r91 = fptosi <2 x float> undef to <2 x i1>
-; CHECK-MVE-RECIP-NEXT:  Cost Model: Found an estimated cost of 36 for instruction: %r92 = fptoui <2 x float> undef to <2 x i8>
-; CHECK-MVE-RECIP-NEXT:  Cost Model: Found an estimated cost of 36 for instruction: %r93 = fptosi <2 x float> undef to <2 x i8>
-; CHECK-MVE-RECIP-NEXT:  Cost Model: Found an estimated cost of 36 for instruction: %r94 = fptoui <2 x float> undef to <2 x i16>
-; CHECK-MVE-RECIP-NEXT:  Cost Model: Found an estimated cost of 36 for instruction: %r95 = fptosi <2 x float> undef to <2 x i16>
-; CHECK-MVE-RECIP-NEXT:  Cost Model: Found an estimated cost of 36 for instruction: %r96 = fptoui <2 x float> undef to <2 x i32>
-; CHECK-MVE-RECIP-NEXT:  Cost Model: Found an estimated cost of 36 for instruction: %r97 = fptosi <2 x float> undef to <2 x i32>
+; CHECK-MVE-RECIP-NEXT:  Cost Model: Found an estimated cost of 4 for instruction: %r90 = fptoui <2 x float> undef to <2 x i1>
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preames wrote:

To address this, could we key the new code off TLI->getTypeAction instead?  That would allow us to make the distinction between TypeWidenVector and the other cases?

https://github.com/llvm/llvm-project/pull/107303