Use cast<> instead of dyn_cast to remove llvm_unreachable. NFC.

This code was checking if we are an ICmpInst or FCmpInst then throwing
unreachable if we are neither.  We must be one or the other, so use a
cast on the FCmpInst case to ensure that we are that case.  Then we can
avoid having an unreachable but still catch an error if we ever had another
subclass of CmpInst.

llvm-svn: 242264

1 files changed, 2 insertions, 4 deletions

diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index 7d1e1f86913..9cf3d378f3e 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -1375,13 +1375,11 @@ SelectionDAGBuilder::EmitBranchForMergedCondition(const Value *Cond,
       ISD::CondCode Condition;
       if (const ICmpInst *IC = dyn_cast<ICmpInst>(Cond)) {
         Condition = getICmpCondCode(IC->getPredicate());
-      } else if (const FCmpInst *FC = dyn_cast<FCmpInst>(Cond)) {
+      } else {
+        const FCmpInst *FC = cast<FCmpInst>(Cond);
         Condition = getFCmpCondCode(FC->getPredicate());
         if (TM.Options.NoNaNsFPMath)
           Condition = getFCmpCodeWithoutNaN(Condition);
-      } else {
-        (void)Condition; // silence warning.
-        llvm_unreachable("Unknown compare instruction");
       }
 
       CaseBlock CB(Condition, BOp->getOperand(0), BOp->getOperand(1), nullptr,