[PATCH] D154565: [InstCombine] Fold icmps comparing uadd_sat with a constant

[Nikita Popov via Phabricator via llvm-commits]

nikic accepted this revision.
nikic added a comment.
This revision is now accepted and ready to land.

LGTM



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Comment at: llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp:3643
+  // evaluates to true. For the LHS, this means the exact inverse of the range
+  // of values of the above.
+  ConstantRange C1 = ConstantRange::makeExactNoWrapRegion(
----------------
I feel like this comment is largely redundant with the one above...


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Comment at: llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp:3651
   ConstantRange C2 = ConstantRange::makeExactICmpRegion(Pred, C);
-  C2 = C2.add(*COp1);
+  if (IntrinsicIsAddition)
+    C2 = C2.sub(*COp1);
----------------
This variable is only used here -- check `II->getBinaryOp() == Instruction::Add` instead?


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https://reviews.llvm.org/D154565