[PATCH] D15515: [AArch64] Add missing extract extend patterns

[Matthew Simpson via llvm-commits]

mssimpso added a comment.

Thanks very much for the quick reply, Silviu! Please see my response inline.


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Comment at: lib/Target/AArch64/AArch64InstrInfo.td:3809
@@ -3808,1 +3808,3 @@
 
+def : Pat<(sext_inreg (i64 (anyext (vector_extract (v16i8 V128:$Rn),
+            VectorIndexB:$idx))), i8),
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sbaranga wrote:
> Any idea why we don't have (anyext (vector_extract (...) ) -> vector_extract ( )?
> 
> I see that vector_extract is EXTRACT_VECTOR_ELT, which according to ISDOpcodes.h should be able to perform the anyext operation. If that would happen, wouldn't one of the patterns above match this?
I see what you're getting at, but as far as I know (please correct me if I'm wrong), "vector_extract" can't be used in an output pattern.


http://reviews.llvm.org/D15515