[PATCH] D116168: [NFC] Method for evaluation of FCmpInst for constant operands

[Serge Pavlov via Phabricator via llvm-commits]

sepavloff added inline comments.


================
Comment at: llvm/lib/IR/ConstantFold.cpp:1804
     const APFloat &C2V = cast<ConstantFP>(C2)->getValueAPF();
-    APFloat::cmpResult R = C1V.compare(C2V);
-    switch (pred) {
-    default: llvm_unreachable("Invalid FCmp Predicate");
-    case FCmpInst::FCMP_FALSE: return Constant::getNullValue(ResultTy);
-    case FCmpInst::FCMP_TRUE:  return Constant::getAllOnesValue(ResultTy);
-    case FCmpInst::FCMP_UNO:
-      return ConstantInt::get(ResultTy, R==APFloat::cmpUnordered);
-    case FCmpInst::FCMP_ORD:
-      return ConstantInt::get(ResultTy, R!=APFloat::cmpUnordered);
-    case FCmpInst::FCMP_UEQ:
-      return ConstantInt::get(ResultTy, R==APFloat::cmpUnordered ||
-                                        R==APFloat::cmpEqual);
-    case FCmpInst::FCMP_OEQ:
-      return ConstantInt::get(ResultTy, R==APFloat::cmpEqual);
-    case FCmpInst::FCMP_UNE:
-      return ConstantInt::get(ResultTy, R!=APFloat::cmpEqual);
-    case FCmpInst::FCMP_ONE:
-      return ConstantInt::get(ResultTy, R==APFloat::cmpLessThan ||
-                                        R==APFloat::cmpGreaterThan);
-    case FCmpInst::FCMP_ULT:
-      return ConstantInt::get(ResultTy, R==APFloat::cmpUnordered ||
-                                        R==APFloat::cmpLessThan);
-    case FCmpInst::FCMP_OLT:
-      return ConstantInt::get(ResultTy, R==APFloat::cmpLessThan);
-    case FCmpInst::FCMP_UGT:
-      return ConstantInt::get(ResultTy, R==APFloat::cmpUnordered ||
-                                        R==APFloat::cmpGreaterThan);
-    case FCmpInst::FCMP_OGT:
-      return ConstantInt::get(ResultTy, R==APFloat::cmpGreaterThan);
-    case FCmpInst::FCMP_ULE:
-      return ConstantInt::get(ResultTy, R!=APFloat::cmpGreaterThan);
-    case FCmpInst::FCMP_OLE:
-      return ConstantInt::get(ResultTy, R==APFloat::cmpLessThan ||
-                                        R==APFloat::cmpEqual);
-    case FCmpInst::FCMP_UGE:
-      return ConstantInt::get(ResultTy, R!=APFloat::cmpLessThan);
-    case FCmpInst::FCMP_OGE:
-      return ConstantInt::get(ResultTy, R==APFloat::cmpGreaterThan ||
-                                        R==APFloat::cmpEqual);
-    }
+    CmpInst::Predicate Predicate = CmpInst::Predicate(pred);
+    return ConstantInt::get(ResultTy, FCmpInst::compare(C1V, C2V, Predicate));
----------------
nikic wrote:
> It's pretty weird that this function accepts the predicate as `unsigned short`. Would be great to switch it to `CmpInst::Predicate` (separately).
The patch is here: D116379.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D116168/new/

https://reviews.llvm.org/D116168