[PATCH] D34029: Infer lowest bits of an integer Multiply when the low bits of the operands are known

[Eli Friedman via Phabricator via llvm-commits]

efriedma added a subscriber: nlopes.
efriedma added a comment.

I like to see a more formal proof for this sort of thing... but I don't have enough time to mess with alive.  Got as far as http://rise4fun.com/Alive/a7O .



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Comment at: lib/Analysis/ValueTracking.cpp:365
+  // of both operands. Depending on number of trailing zeros, we can
+  // infer more bits, because (a*b) <=> ((a/m) * (b/s)) * (m*n) assuming
+  // a and b are divisible by m and n respectively.
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Is this supposed "b/n", rather than "b/s"?


https://reviews.llvm.org/D34029