diff --git a/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp b/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp
index c44fe9db6e3a..2cbb810fc15e 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp
@@ -639,6 +639,10 @@ Instruction *InstCombiner::visitSelectInst(SelectInst &SI) {
             Value *NegVal;  // Compute -Z
             if (Constant *C = dyn_cast<Constant>(SubOp->getOperand(1))) {
               NegVal = ConstantExpr::getNeg(C);
+            } else if (SI.getType()->isFloatingPointTy()) {
+              NegVal = InsertNewInstBefore(
+                    BinaryOperator::CreateFNeg(SubOp->getOperand(1),
+                                              "tmp"), SI);
             } else {
               NegVal = InsertNewInstBefore(
                     BinaryOperator::CreateNeg(SubOp->getOperand(1),
@@ -654,7 +658,10 @@ Instruction *InstCombiner::visitSelectInst(SelectInst &SI) {
                                  NewFalseOp, SI.getName() + ".p");
 
             NewSel = InsertNewInstBefore(NewSel, SI);
-            return BinaryOperator::CreateAdd(SubOp->getOperand(0), NewSel);
+            if (SI.getType()->isFloatingPointTy())
+              return BinaryOperator::CreateFAdd(SubOp->getOperand(0), NewSel);
+            else
+              return BinaryOperator::CreateAdd(SubOp->getOperand(0), NewSel);
           }
         }
       }
diff --git a/llvm/test/Transforms/InstCombine/select-crash.ll b/llvm/test/Transforms/InstCombine/select-crash.ll
new file mode 100644
index 000000000000..8ee33690d8ce
--- /dev/null
+++ b/llvm/test/Transforms/InstCombine/select-crash.ll
@@ -0,0 +1,20 @@
+; RUN: opt < %s -instcombine -S | FileCheck %s
+; Formerly crashed, PR8490.
+
+define fastcc double @gimp_operation_color_balance_map(float %value, double %highlights) nounwind readnone inlinehint {
+entry:
+; CHECK: gimp_operation_color_balance_map
+; CHECK: fsub double -0.000000
+  %conv = fpext float %value to double
+  %div = fdiv double %conv, 1.600000e+01
+  %add = fadd double %div, 1.000000e+00
+  %div1 = fdiv double 1.000000e+00, %add
+  %sub = fsub double 1.075000e+00, %div1
+  %sub24 = fsub double 1.000000e+00, %sub
+  %add26 = fadd double %sub, 1.000000e+00
+  %cmp86 = fcmp ogt double %highlights, 0.000000e+00
+  %cond90 = select i1 %cmp86, double %sub24, double %add26
+  %mul91 = fmul double %highlights, %cond90
+  %add94 = fadd double undef, %mul91
+  ret double %add94
+}