fixup! Use m_SpecificICmp

Author: topperc

llvm/lib/CodeGen/ExpandMemCmp.cpp

@@ -668,7 +668,7 @@ Value *MemCmpExpansion::getMemCmpOneBlock() {
   // We can generate more optimal code with a smaller number of operations
   if (CI->hasOneUser()) {
     auto *UI = cast<Instruction>(*CI->user_begin());
-    CmpPredicate Pred;
+    CmpPredicate Pred = ICmpInst::Predicate::BAD_ICMP_PREDICATE;
     uint64_t Shift;
     bool NeedsZExt = false;
     // This is a special case because instead of checking if the result is less
@@ -680,19 +680,17 @@ Value *MemCmpExpansion::getMemCmpOneBlock() {
         Shift == (CI->getType()->getIntegerBitWidth() - 1)) {
       Pred = ICmpInst::ICMP_SLT;
       NeedsZExt = true;
-    } else if (match(UI, m_ICmp(Pred, m_Specific(CI), m_Zero()))) {
-      // Compare with 0. Pred is already set.
-    } else if (match(UI, m_ICmp(Pred, m_Specific(CI), m_AllOnes())) &&
-               Pred == ICmpInst::ICMP_SGT) {
+    } else if (match(UI, m_SpecificICmp(ICmpInst::ICMP_SGT, m_Specific(CI),
+                                        m_AllOnes()))) {
       // Adjust predicate as if it compared with 0.
       Pred = ICmpInst::ICMP_SGE;
-    } else if (match(UI, m_ICmp(Pred, m_Specific(CI), m_One())) &&
-               Pred == ICmpInst::ICMP_SLT) {
+    } else if (match(UI, m_SpecificICmp(ICmpInst::ICMP_SLT, m_Specific(CI),
+                                        m_One()))) {
       // Adjust predicate as if it compared with 0.
       Pred = ICmpInst::ICMP_SLE;
     } else {
-      // No match, invalidate Pred.
-      Pred = ICmpInst::Predicate::BAD_ICMP_PREDICATE;
+      // In case of a successful match this call will set `Pred` variable
+      match(UI, m_ICmp(Pred, m_Specific(CI), m_Zero()));
     }
     // Generate new code and remove the original memcmp call and the user
     if (ICmpInst::isSigned(Pred)) {