[PATCH] D47037: [EarlyCSE] Improve EarlyCSE of some absolute value cases.

[Sanjay Patel via Phabricator via llvm-commits]

spatel added inline comments.


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Comment at: lib/Analysis/ValueTracking.cpp:4574-4576
+      // Set RHS to the negate operand. LHS was assigned to CmpLHS earlier.
+      RHS = (CmpLHS == TrueVal) ? FalseVal : TrueVal;
 
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This new ABS/NABS behavior should be documented in the header comment.


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Comment at: lib/Transforms/Scalar/EarlyCSE.cpp:164-167
+  if (SPF == SPF_ABS || SPF == SPF_NABS) {
+    // ABS/NABS always puts the input in A and its negation in B.
+    return hash_combine(Inst->getOpcode(), SPF, A, B);
+  }
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This is dead code unless we remove the ABS/NABS checks above here?


https://reviews.llvm.org/D47037