port 574f6fe1 (r37701)

  original commit message:
  Previously, the following schedule fragment:

   1: Parameter[0](0)
   2: Parameter[1](0)
   7: Int32Constant[1]
   8: Int32Sub(2, 7)
   9: Load[kRepTagged|kTypeAny](1, 8)

  would generate the following code (on ia32):

   mov eax,[ebp+0x8]
   mov ecx,[ebp+0xc]
   sub eax,0x1
   mov eax,[eax+ecx*1]

  Now it generates:

   mov eax,[ebp+0x8]
   mov ecx,[ebp+0xc]
   mov eax,[eax+ecx*1-1]

  Similar pattern matching also now works on x64.

BUG=

Review-Url: https://codereview.chromium.org/2151753002
Cr-Commit-Position: refs/heads/master@{#37738}