[llvm] r305086 - [LazyValueInfo] Don't run the more complex predicate handling code for EQ and NE in getPredicateResult

[Craig Topper via llvm-commits]

Author: ctopper
Date: Fri Jun  9 11:16:20 2017
New Revision: 305086

URL: http://llvm.org/viewvc/llvm-project?rev=305086&view=rev
Log:
[LazyValueInfo] Don't run the more complex predicate handling code for EQ and NE in getPredicateResult

Summary:
Unless I'm mistaken, the special handling for EQ/NE should cover everything and there is no reason to fallthrough to the more complex code. For that matter I'm not sure there's any reason to special case EQ/NE other than avoiding creating temporary ConstantRanges.

This patch moves the complex code into an else so we only do it when we are handling a predicate other than EQ/NE.

Reviewers: anna, reames, resistor, Farhana

Reviewed By: anna

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D34000

Modified:
    llvm/trunk/lib/Analysis/LazyValueInfo.cpp

Modified: llvm/trunk/lib/Analysis/LazyValueInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/LazyValueInfo.cpp?rev=305086&r1=305085&r2=305086&view=diff
==============================================================================
--- llvm/trunk/lib/Analysis/LazyValueInfo.cpp (original)
+++ llvm/trunk/lib/Analysis/LazyValueInfo.cpp Fri Jun  9 11:16:20 2017
@@ -1692,15 +1692,15 @@ static LazyValueInfo::Tristate getPredic
 
       if (CR.isSingleElement())
         return LazyValueInfo::False;
+    } else {
+      // Handle more complex predicates.
+      ConstantRange TrueValues = ConstantRange::makeExactICmpRegion(
+          (ICmpInst::Predicate)Pred, CI->getValue());
+      if (TrueValues.contains(CR))
+        return LazyValueInfo::True;
+      if (TrueValues.inverse().contains(CR))
+        return LazyValueInfo::False;
     }
-
-    // Handle more complex predicates.
-    ConstantRange TrueValues = ConstantRange::makeExactICmpRegion(
-        (ICmpInst::Predicate)Pred, CI->getValue());
-    if (TrueValues.contains(CR))
-      return LazyValueInfo::True;
-    if (TrueValues.inverse().contains(CR))
-      return LazyValueInfo::False;
     return LazyValueInfo::Unknown;
   }