[PATCH] D78922: [CostModel] Remove getExtCost

[Dave Green via Phabricator via llvm-commits]

dmgreen added a comment.
Herald added a subscriber: wuzish.

It may be better to separate out the "add I to getCastInstrCost" change, which is something I agree with but seems to deserve it's own patch to get the details correct.



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Comment at: llvm/test/Analysis/CostModel/ARM/cast.ll:1669
 ; CHECK-NEON-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %r11 = zext i32 %loadi32 to i64
-; CHECK-NEON-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %v0 = sext <8 x i8> %loadv8i8 to <8 x i16>
-; CHECK-NEON-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %v1 = zext <8 x i8> %loadv8i8 to <8 x i16>
-; CHECK-NEON-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %v2 = sext <4 x i8> %loadv4i8 to <4 x i32>
-; CHECK-NEON-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %v3 = zext <4 x i8> %loadv4i8 to <4 x i32>
-; CHECK-NEON-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %v4 = sext <2 x i8> %loadv2i8 to <2 x i64>
-; CHECK-NEON-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %v5 = zext <2 x i8> %loadv2i8 to <2 x i64>
+; CHECK-NEON-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: %v0 = sext <8 x i8> %loadv8i8 to <8 x i16>
+; CHECK-NEON-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: %v1 = zext <8 x i8> %loadv8i8 to <8 x i16>
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I don't think this should be free for Neon, as far as I understand. It doesn't fold the extend into the load like it would for MVE or scalar.


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  https://reviews.llvm.org/D78922/new/

https://reviews.llvm.org/D78922