[PATCH] D64707: [x86] try harder to form LEA from ADD to avoid flag conflicts (PR40483)

[Sanjay Patel via Phabricator via llvm-commits]

spatel marked an inline comment as done.
spatel added inline comments.


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Comment at: llvm/lib/Target/X86/X86ISelDAGToDAG.cpp:2487
+    };
+    if (isMathWithFlags(N.getOperand(0)) && isMathWithFlags(N.getOperand(1)))
+      Complexity++;
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grandinj wrote:
> Should this not be an || condition ?
It could be || (and I tried that initially), but I saw possible regressions (missed load folding) with that logic.

Given that this is a heuristic, it's hard to determine statically when it will be profitable. 

Ok if I add a TODO comment about extending this in a follow-up patch? If we can recover the load folding, I agree that using || would be better.


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