[PATCH] D55373: [LSR] Generate formulae to enable more indexed accesses

[Gil Rapaport via Phabricator via llvm-commits]

gilr added inline comments.


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Comment at: lib/Target/ARM/ARMTargetTransformInfo.h:99
+      return false;
+    return ST->isMClass() && ST->isThumb2() && L->getNumBlocks() == 1;
+  }
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samparker wrote:
> gilr wrote:
> > Is the single-block constraint due to CodeGen's single-block optimization scope? (If so, then IINM it's not target-specific)
> No, its not because of ISel restrictions or anything like that. It's because the transform is only likely to be useful is the address can be kept in the same register - which becomes increasingly less likely once multiple blocks are considered.
So both the code-size and single-block heuristics seem target-independent. Why not do this in LSR?


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D55373/new/

https://reviews.llvm.org/D55373