Index: llvm/lib/IR/Constants.cpp
===================================================================
--- llvm/lib/IR/Constants.cpp
+++ llvm/lib/IR/Constants.cpp
@@ -287,11 +287,11 @@
     return false;
 
   // They may still be identical element-wise (if they have `undef`s).
-  // FIXME: This crashes on FP vector constants.
-  return match(ConstantExpr::getICmp(ICmpInst::Predicate::ICMP_EQ,
-                                     const_cast<Constant *>(this),
-                                     cast<Constant>(Y)),
-               m_One());
+  // Bitcast to integer to allow exact bitwise comparison for all types.
+  Type *IntTy = VectorType::getInteger(cast<VectorType>(Ty));
+  Constant *C0 = ConstantExpr::getBitCast(const_cast<Constant *>(this), IntTy);
+  Constant *C1 = ConstantExpr::getBitCast(cast<Constant>(Y), IntTy);
+  return match(ConstantExpr::getICmp(ICmpInst::ICMP_EQ, C0, C1), m_One());
 }
 
 bool Constant::containsUndefElement() const {
Index: llvm/unittests/IR/ConstantsTest.cpp
===================================================================
--- llvm/unittests/IR/ConstantsTest.cpp
+++ llvm/unittests/IR/ConstantsTest.cpp
@@ -607,7 +607,6 @@
   EXPECT_FALSE(C12U1->isElementWiseEqual(C12U2));
   EXPECT_FALSE(C12U21->isElementWiseEqual(C12U2));
 
-/* FIXME: This will crash.
   Type *FltTy = Type::getFloatTy(Context);
   Constant *CFU = UndefValue::get(FltTy);
   Constant *CF1 = ConstantFP::get(FltTy, 1.0);
@@ -621,7 +620,6 @@
   EXPECT_TRUE(CF12U1->isElementWiseEqual(CF1211));
   EXPECT_FALSE(CF12U2->isElementWiseEqual(CF12U1));
   EXPECT_FALSE(CF12U1->isElementWiseEqual(CF12U2));
-*/
 }
 
 }  // end anonymous namespace