[llvm] IR: introduce CmpInst::is{Eq,Ne}Equivalence (PR #111979)

[Matt Arsenault via llvm-commits]

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@@ -3472,30 +3473,20 @@ bool CmpInst::isEquality(Predicate P) {
 }
 
 // Returns true if either operand of CmpInst is a provably non-zero
-// floating-point constant. If both operands are constants, simply return the
-// equality of the constants.
+// floating-point constant.
 static bool hasNonZeroFPOperands(const CmpInst *Cmp) {
   auto *LHS = dyn_cast<Constant>(Cmp->getOperand(0));
   auto *RHS = dyn_cast<Constant>(Cmp->getOperand(1));
-  if (LHS && RHS)
-    return LHS == RHS;
   if (auto *Const = LHS ? LHS : RHS) {
-    if (auto *ConstFP = dyn_cast<ConstantFP>(Const)) {
-      if (!ConstFP->isZero())
-        return true;
-    } else if (auto *ConstVec = dyn_cast<ConstantVector>(Const)) {
-      if (auto *SplatCFP =
-              dyn_cast_or_null<ConstantFP>(ConstVec->getSplatValue())) {
-        if (!SplatCFP->isZero())
-          return true;
-      }
-    }
+    using namespace llvm::PatternMatch;
+    return Const->isNormalFP() && match(Const, m_NonZeroFP());
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arsenm wrote:

Redundant handling, and confusing to split the FP predicate. Infinities are also not complicated 

https://github.com/llvm/llvm-project/pull/111979