Index: llvm/test/tools/llvm-reduce/remove-operands-fp.ll
===================================================================
--- /dev/null
+++ llvm/test/tools/llvm-reduce/remove-operands-fp.ll
@@ -0,0 +1,63 @@
+; Test that llvm-reduce can reduce floating point operands
+;
+; RUN: llvm-reduce --abort-on-invalid-reduction --delta-passes=operands-undef --test FileCheck --test-arg --check-prefixes=CHECK-INTERESTINGNESS --test-arg %s --test-arg --input-file %s -o %t
+; RUN: FileCheck --check-prefixes=CHECK,UNDEF %s < %t
+
+; RUN: llvm-reduce --abort-on-invalid-reduction --delta-passes=operands-one --test FileCheck --test-arg --check-prefixes=CHECK-INTERESTINGNESS --test-arg %s --test-arg --input-file %s -o %t
+; RUN: FileCheck --check-prefixes=CHECK,ONE %s < %t
+
+; RUN: llvm-reduce --abort-on-invalid-reduction --delta-passes=operands-zero --test FileCheck --test-arg --check-prefixes=CHECK-INTERESTINGNESS --test-arg %s --test-arg --input-file %s -o %t
+; RUN: FileCheck --check-prefixes=CHECK,ZERO %s < %t
+
+; RUN: llvm-reduce --test FileCheck --test-arg --check-prefixes=CHECK-INTERESTINGNESS --test-arg %s --test-arg --input-file %s -o %t
+; RUN: FileCheck --check-prefixes=CHECK,ZERO %s < %t
+
+; CHECK-INTERESTINGNESS: = fadd float %
+; CHECK-INTERESTINGNESS: = fadd float
+
+; CHECK-INTERESTINGNESS: = fadd <2 x float>
+; CHECK-INTERESTINGNESS: = fadd <2 x float>
+; CHECK-INTERESTINGNESS: = fadd <2 x float>
+
+; CHECK-LABEL: define void @foo(
+
+; UNDEF: %fadd0 = fadd float %arg0, undef
+; UNDEF: %fadd1 = fadd float undef, undef
+; UNDEF: %fadd2 = fadd <2 x float> undef, undef
+; UNDEF: %fadd3 = fadd <2 x float> undef, undef
+; UNDEF: %fadd4 = fadd <2 x float> undef, <float 1.000000e+00, float 1.000000e+00>
+
+; ZERO: %fadd0 = fadd float %arg0, 0.000000e+00
+; ZERO: %fadd1 = fadd float 0.000000e+00, 0.000000e+00
+; ZERO: %fadd2 = fadd <2 x float> zeroinitializer, zeroinitializer
+; ZERO: %fadd3 = fadd <2 x float> zeroinitializer, zeroinitializer
+; ZERO: %fadd4 = fadd <2 x float> zeroinitializer, zeroinitializer
+
+; ONE: %fadd0 = fadd float %arg0, 1.000000e+00
+; ONE: %fadd1 = fadd float 1.000000e+00, 1.000000e+00
+; ONE: %fadd2 = fadd <2 x float> <float 1.000000e+00, float 1.000000e+00>, <float 1.000000e+00, float 1.000000e+00>
+; ONE: %fadd3 = fadd <2 x float> <float 1.000000e+00, float 1.000000e+00>, <float 1.000000e+00, float 1.000000e+00>
+; ONE: %fadd4 = fadd <2 x float> <float 1.000000e+00, float 1.000000e+00>, <float 1.000000e+00, float 1.000000e+00>
+
+declare float @llvm.fma.f32(float, float, float)
+declare <2 x float> @llvm.fma.v2f32(<2 x float>, <2 x float>, <2 x float>)
+
+define void @foo(float %arg0, float %arg1, <2 x float> %arg2, <2 x float> %arg3) {
+bb0:
+  %fadd0 = fadd float %arg0, %arg1
+  store float %fadd0, float* undef
+
+  %fadd1 = fadd float %arg0, %arg1
+  store float %fadd1, float* undef
+
+  %fadd2 = fadd <2 x float> %arg2, %arg3
+  store <2 x float> %fadd2, <2 x float>* undef
+
+  %fadd3 = fadd <2 x float> %arg2, %arg3
+  store <2 x float> %fadd3, <2 x float>* undef
+
+  %fadd4 = fadd <2 x float> %arg2, <float 1.0, float 1.0>
+  store <2 x float> %fadd4, <2 x float>* undef
+
+  ret void
+}
Index: llvm/tools/llvm-reduce/deltas/ReduceOperands.cpp
===================================================================
--- llvm/tools/llvm-reduce/deltas/ReduceOperands.cpp
+++ llvm/tools/llvm-reduce/deltas/ReduceOperands.cpp
@@ -11,9 +11,11 @@
 #include "llvm/IR/InstIterator.h"
 #include "llvm/IR/InstrTypes.h"
 #include "llvm/IR/Operator.h"
+#include "llvm/IR/PatternMatch.h"
 #include "llvm/IR/Type.h"
 
 using namespace llvm;
+using namespace PatternMatch;
 
 static void
 extractOperandsFromModule(Oracle &O, Module &Program,
@@ -39,6 +41,12 @@
   return C && C->isNullValue();
 }
 
+static bool isZeroOrOneFP(Value *Op) {
+  const APFloat *C;
+  return match(Op, m_APFloat(C)) &&
+         ((C->isZero() && !C->isNegative()) || C->isExactlyValue(1.0));
+}
+
 static bool shouldReduceOperand(Use &Op) {
   Type *Ty = Op->getType();
   if (Ty->isLabelTy() || Ty->isMetadataTy())
@@ -70,14 +78,27 @@
 void llvm::reduceOperandsOneDeltaPass(TestRunner &Test) {
   errs() << "*** Reducing Operands to one...\n";
   auto ReduceValue = [](Use &Op) -> Value * {
-    // TODO: support floats
     if (!shouldReduceOperand(Op))
       return nullptr;
-    auto *Ty = dyn_cast<IntegerType>(Op->getType());
-    if (!Ty)
-      return nullptr;
-    // Don't replace existing ones and zeroes.
-    return (isOne(Op) || isZero(Op)) ? nullptr : ConstantInt::get(Ty, 1);
+
+    Type *Ty = Op->getType();
+    if (auto *IntTy = dyn_cast<IntegerType>(Ty)) {
+      // Don't replace existing ones and zeroes.
+      return (isOne(Op) || isZero(Op)) ? nullptr : ConstantInt::get(IntTy, 1);
+    }
+
+    if (Ty->isFloatingPointTy())
+      return isZeroOrOneFP(Op) ? nullptr : ConstantFP::get(Ty, 1.0);
+
+    if (VectorType *VT = dyn_cast<VectorType>(Ty)) {
+      if (isZeroOrOneFP(Op))
+        return nullptr;
+
+      return ConstantVector::getSplat(
+          VT->getElementCount(), ConstantFP::get(VT->getElementType(), 1.0));
+    }
+
+    return nullptr;
   };
   runDeltaPass(Test, [ReduceValue](Oracle &O, Module &Program) {
     extractOperandsFromModule(O, Program, ReduceValue);