[Mlir-commits] [mlir] [mlir][Transforms] Dialect conversion: Add missing "else if" branch (PR #101148)

[Matthias Springer]

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@@ -1328,15 +1328,19 @@ Block *ConversionPatternRewriterImpl::applySignatureConversion(
     mapping.map(origArg, argMat);
     appendRewrite<ReplaceBlockArgRewrite>(block, origArg);
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matthias-springer wrote:

There are two mapping steps: `origArg -> argMat -> targetMat`. Note that the mapping is *not* overwritten here. In the second step, we map `argMat`, not `origArg`.

And we also generate two `unrealized_conversion_cast` ops. Such casts cannot be folded, unless they `type(origArg) == type(targetMat)`.

It was actually on purpose that two casts in a row are generated here. The first one is an argument materialization and the second one is target materialization. Depending on the configuration of the type converter, we may not generate `unrealized_conversion_cast`, but custom ops.


https://github.com/llvm/llvm-project/pull/101148