10 Commits

Author SHA1 Message Date
Nick Lewycky
41a9bdab7b 'i8 full-range' sign extended to i16 should equal [-128, 128) not [-128, 127).
Found by Daniel Dunbar and KLEE.

llvm-svn: 75448
2009-07-13 04:17:23 +00:00
Nick Lewycky
fee90bcb80 Multiply was very wrong for wrapped ranges. This supplies a half-fix that will
generally return Full on all wrapped inputs. "Fixes" PR4545.

llvm-svn: 75444
2009-07-13 03:27:41 +00:00
Nick Lewycky
7280c39dc7 Fix a bug summing two full sets. The overflow checking doesn't handle sets as
large as the full set, only those one size smaller. Thanks to Daniel Dunbar
who found this bug using Klee!

llvm-svn: 75443
2009-07-13 02:49:08 +00:00
Nick Lewycky
dc5ef94320 Implement udiv for ConstantRanges.
llvm-svn: 75413
2009-07-12 05:18:18 +00:00
Nick Lewycky
7cb010e885 This is not overly conservative.
Some = [10, 2730). A subset of that is [1024..2048) which covers every possible
10-bit pattern.

llvm-svn: 75411
2009-07-12 02:28:40 +00:00
Nick Lewycky
6663d6ad6f Implement ConstantRange::multiply based on the code in LoopVR.
llvm-svn: 75410
2009-07-12 02:19:05 +00:00
Nick Lewycky
3e43cd4105 Fix handling of max and full set.
A full set is a constant range that represents any number. If you take the
umax of that and [5, 10) you end up with [5, INT_MAX] because the values less
than 5 would be umax's against a value which is at least 5.

llvm-svn: 75372
2009-07-11 19:22:21 +00:00
Nick Lewycky
d2817afb0e Break the world's largest unit test down a few logical lines. No semantic
changes.

llvm-svn: 75369
2009-07-11 18:43:20 +00:00
Dan Gohman
8a58b8f83b Revert the part of 75177 that split ConstantRange into two classes, and
merge the new functionality and unittests into ConstantRange. Thanks to
Nick Lewycky for pointing out that it isn't necessary to have two separate
classes here.

llvm-svn: 75191
2009-07-09 23:16:10 +00:00
Dan Gohman
33251eff97 Add a ConstantSignedRange class, which does for signed integers
what ConstantRange does for unsigned integers. Factor out a
common base class for common functionality.

Add some new functions for performing arithmetic on constant
ranges. Some of these are currently just stubbed out with
conservative implementations.

Add unittests for ConstantRange and ConstantSignedRange.

llvm-svn: 75177
2009-07-09 22:07:27 +00:00