On Mar 2, 2007, at 3:40 PM, Reid Spencer wrote: > On Fri, 2007-03-02 at 15:35 -0800, Chris Lattner wrote: >> On Mar 2, 2007, at 3:31 PM, Reid Spencer wrote: >> >> >>> + // Guard against huge trip counts. This also guards against >>> assertions in >>> + // APInt from the use of getZExtValue, below. >>> + if (TripCountC->getValue().getActiveBits() > 32) >>> return Changed; // More than 2^32 iterations??? >>> >>> + uint64_t TripCountFull = TripCountC->getZExtValue(); >>> + if (TripCountFull == 0) >>> + return Changed; // Zero iteraitons? >>> + >> >> Won't this still assert on 'i128 16' ? > > No. getZExtValue() doesn't look at the bit width, it looks at the > precision of the value. Regardless of the bit width, if the value fits > in 64 bits, it allows it. If not, it asserts. Which is why I check > "getActiveBits() > 32" to limit trip counts to < 2^32. This makes the > getZExtValue() safe.
Ok, nifty. > That precision check is another reason why I'm changing things like: > > if (CI->getZExtValue() == 1) > > into > > if (CI->isOne()) > > because its cheaper :) Woot! -Chris _______________________________________________ llvm-commits mailing list llvm-commits@cs.uiuc.edu http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits
