[ConstantRange] Split makeICmpRegion in two.

Summary:
This change splits `makeICmpRegion` into `makeAllowedICmpRegion` and
`makeSatisfyingICmpRegion` with slightly different contracts.  The first
one is useful for determining what values some expression //may// take,
given that a certain `icmp` evaluates to true.  The second one is useful
for determining what values are guaranteed to //satisfy// a given
`icmp`.

Reviewers: nlewycky

Reviewed By: nlewycky

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D8345

llvm-svn: 232575

1 files changed, 2 insertions, 2 deletions

diff --git a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp
index 896da1d3a6b..b45a256bc24 100644
--- a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp
+++ b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp
@@ -421,8 +421,8 @@ private:
     }
 
     // If we have "x ult 3", for example, then we can add 0,1,2 to the set.
-    ConstantRange Span = ConstantRange::makeICmpRegion(ICI->getPredicate(),
-                                                       C->getValue());
+    ConstantRange Span = ConstantRange::makeAllowedICmpRegion(
+        ICI->getPredicate(), C->getValue());
 
     // Shift the range if the compare is fed by an add. This is the range
     // compare idiom as emitted by instcombine.