[PATCH] D159406: [SelectionDAG] Generalise SelectionDAG::computeOverflowKind to support other opcodes

[Simon Pilgrim via Phabricator via llvm-commits]

RKSimon added a comment.

regarding test coverage - its ok to add tests in the patch to show the new coverage, once the patch is close to being accepted a reviewer might ask that the tests be pushed first so that the patch shows the codegen improvement.

Alternatively you can create a parent-child relationship between patches, but since LLVM is moving to github PRs this month I'd possibly recommend you just create a stacked PR instead



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Comment at: llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp:4091
+  ConstantRange N1Range = ConstantRange::fromKnownBits(N1Known, false);
+  return mapOverflowResult(N0Range.signedAddMayOverflow(N1Range));
 }
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remove this and put it in its own patch with test coverage


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Comment at: llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp:4132
+  ConstantRange N1Range = ConstantRange::fromKnownBits(N1Known, false);
+  return mapOverflowResult(N0Range.signedSubMayOverflow(N1Range));
 }
----------------
remove this and put it in its own patch with test coverage


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Comment at: llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp:4145
+  ConstantRange N1Range = ConstantRange::fromKnownBits(N1Known, false);
+  return mapOverflowResult(N0Range.unsignedSubMayOverflow(N1Range));
 }
----------------
remove this and put it in its own patch with test coverage


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D159406/new/

https://reviews.llvm.org/D159406