[InstSimplify] use m_APFloat to simplify fcmp folds; NFCI

llvm-svn: 319043

diff --git a/llvm/lib/Analysis/InstructionSimplify.cpp b/llvm/lib/Analysis/InstructionSimplify.cpp
index 76af3dc..6bed2f3 100644 (file)
--- a/llvm/lib/Analysis/InstructionSimplify.cpp
+++ b/llvm/lib/Analysis/InstructionSimplify.cpp
@@ -3326,17 +3326,11 @@ static Value *SimplifyFCmpInst(unsigned Predicate, Value *LHS, Value *RHS,
       return getFalse(RetTy);
   }
 
-  // Handle fcmp with constant RHS
-  const ConstantFP *CFP = nullptr;
-  if (const auto *RHSC = dyn_cast<Constant>(RHS)) {
-    if (RHS->getType()->isVectorTy())
-      CFP = dyn_cast_or_null<ConstantFP>(RHSC->getSplatValue());
-    else
-      CFP = dyn_cast<ConstantFP>(RHSC);
-  }
-  if (CFP) {
+  // Handle fcmp with constant RHS.
+  const APFloat *C;
+  if (match(RHS, m_APFloat(C))) {
     // If the constant is a nan, see if we can fold the comparison based on it.
-    if (CFP->getValueAPF().isNaN()) {
+    if (C->isNaN()) {
       if (FCmpInst::isOrdered(Pred)) // True "if ordered and foo"
         return getFalse(RetTy);
       assert(FCmpInst::isUnordered(Pred) &&
@@ -3345,8 +3339,8 @@ static Value *SimplifyFCmpInst(unsigned Predicate, Value *LHS, Value *RHS,
       return getTrue(RetTy);
     }
     // Check whether the constant is an infinity.
-    if (CFP->getValueAPF().isInfinity()) {
-      if (CFP->getValueAPF().isNegative()) {
+    if (C->isInfinity()) {
+      if (C->isNegative()) {
         switch (Pred) {
         case FCmpInst::FCMP_OLT:
           // No value is ordered and less than negative infinity.
@@ -3370,7 +3364,7 @@ static Value *SimplifyFCmpInst(unsigned Predicate, Value *LHS, Value *RHS,
         }
       }
     }
-    if (CFP->getValueAPF().isZero()) {
+    if (C->isZero()) {
       switch (Pred) {
       case FCmpInst::FCMP_UGE:
         if (CannotBeOrderedLessThanZero(LHS, Q.TLI))