[LVI] Handle any predicate in comparisons like icmp <pred> (add Val, Offset), ...

Currently LVI can only gather value constraints from comparisons like:

* icmp <pred> Val, ...
* icmp ult (add Val, Offset), ...

In fact we can handle any predicate in latter comparisons.

Reviewed By: sanjoy

Differential Revision: https://reviews.llvm.org/D23357

llvm-svn: 278493

1 files changed, 2 insertions, 2 deletions

diff --git a/llvm/lib/Analysis/LazyValueInfo.cpp b/llvm/lib/Analysis/LazyValueInfo.cpp
index 5faa975..c5c9027 100644
--- a/llvm/lib/Analysis/LazyValueInfo.cpp
+++ b/llvm/lib/Analysis/LazyValueInfo.cpp
@@ -1191,7 +1191,7 @@ static LVILatticeVal getValueFromICmpCondition(Value *Val, ICmpInst *ICI,
   // range of Val guaranteed by the condition. Recognize comparisons in the from
   // of:
   //  icmp <pred> Val, ...
-  //  icmp ult (add Val, Offset), ...
+  //  icmp <pred> (add Val, Offset), ...
   // The latter is the range checking idiom that InstCombine produces. Subtract
   // the offset from the allowed range for RHS in this case.
 
@@ -1202,7 +1202,7 @@ static LVILatticeVal getValueFromICmpCondition(Value *Val, ICmpInst *ICI,
   }
 
   ConstantInt *Offset = nullptr;
-  if (Predicate == ICmpInst::ICMP_ULT)
+  if (LHS != Val)
     match(LHS, m_Add(m_Specific(Val), m_ConstantInt(Offset)));
 
   if (LHS == Val || Offset) {