[PatternMatch] Generalize m_SpecificInt_ULT() to take ICmpInst::Predicate

As discussed in the original review, this may be useful,
so let's just do it.

llvm-svn: 365652
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
index 4c81819..3a4283a 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
@@ -3316,7 +3316,8 @@
   // Is the new shift amount smaller than the bit width?
   // FIXME: could also rely on ConstantRange.
   unsigned BitWidth = X->getType()->getScalarSizeInBits();
-  if (!match(NewShAmt, m_SpecificInt_ULT(APInt(BitWidth, BitWidth))))
+  if (!match(NewShAmt, m_SpecificInt_ICMP(ICmpInst::Predicate::ICMP_ULT,
+                                          APInt(BitWidth, BitWidth))))
     return nullptr;
   // All good, we can do this fold. The shift is the same that was for X.
   Value *T0 = XShiftOpcode == Instruction::BinaryOps::LShr