Revert "[Reassociate] As the expression tree is rewritten make sure the operands are"

This reverts commit r222142.  This is causing/exposing an execution-time regression
in spec2006/gcc and coremark on AArch64/A57/Ofast.

Conflicts:

	test/Transforms/Reassociate/optional-flags.ll

llvm-svn: 222398
diff --git a/llvm/test/Transforms/Reassociate/mixed-fast-nonfast-fp.ll b/llvm/test/Transforms/Reassociate/mixed-fast-nonfast-fp.ll
index 8ca0ff6..f51c0c1 100644
--- a/llvm/test/Transforms/Reassociate/mixed-fast-nonfast-fp.ll
+++ b/llvm/test/Transforms/Reassociate/mixed-fast-nonfast-fp.ll
@@ -3,9 +3,9 @@
 define float @foo(float %a,float %b, float %c) {
 ; CHECK: %mul3 = fmul float %a, %b
 ; CHECK-NEXT: fmul fast float %c, 2.000000e+00
-; CHECK-NEXT: fadd fast float %b, %factor
-; CHECK-NEXT: fmul fast float %a, %tmp1
-; CHECK-NEXT: fadd fast float %mul3, %tmp2
+; CHECK-NEXT: fadd fast float %factor, %b
+; CHECK-NEXT: fmul fast float %tmp1, %a
+; CHECK-NEXT: fadd fast float %tmp2, %mul3
 ; CHECK-NEXT: ret float
   %mul1 = fmul fast float %a, %c
   %mul2 = fmul fast float %a, %b