return the smallest union of two ranges instead of just any range that happens
to contain the union.

llvm-svn: 76360

all values belonging to the intersection will belong to the resulting range.
The former was inconsistent about that point (either way is fine, just pick
one.) This is part of PR4545.

llvm-svn: 76289

again to Daniel Dunbar and KLEE!

llvm-svn: 75449

Found by Daniel Dunbar and KLEE.

llvm-svn: 75448

generally return Full on all wrapped inputs. "Fixes" PR4545.

llvm-svn: 75444

large as the full set, only those one size smaller. Thanks to Daniel Dunbar
who found this bug using Klee!

llvm-svn: 75443

llvm-svn: 75413

Some = [10, 2730). A subset of that is [1024..2048) which covers every possible
10-bit pattern.

llvm-svn: 75411

llvm-svn: 75410

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

changes.

llvm-svn: 75369

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

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