[PATCH] D68337: [ARM][MVE] Enable extending masked loads

[Dave Green via Phabricator via llvm-commits]

dmgreen added inline comments.


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Comment at: lib/Target/ARM/ARMISelLowering.cpp:14707
 
+  if (auto *Ld = dyn_cast<MaskedLoadSDNode>(ExtVal.getOperand(0))) {
+    if (Ld->isExpandingLoad())
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MVE doesn't support expanding loads, so it would be surprising if we did see one here. Having the check is good though.


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Comment at: lib/Target/ARM/ARMTargetTransformInfo.cpp:499
+  // TODO: Support unaligned accesses?
+  if (!Alignment.hasValue())
+    return false;
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How rare do you think loads with no explicit alignment to be? I think they don't come up from clang, but is it worth leaving them till later?

As far as I understand, if the alignment on the load was missing (value is 0), it is treated as the abi/pref alignment from the datalayout. So will have an alignment of 8 or 16, so will be aligned.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D68337/new/

https://reviews.llvm.org/D68337