)]}'
{
  "commit": "448c16f0f6905460a3d27e728ed0f14a1c08ff69",
  "tree": "ccf870b112136ce897482d95ac50ef4f9f440f46",
  "parents": [
    "2fea26cae5a6b140c67e18aec3dcf645a16694d5"
  ],
  "author": {
    "name": "John Porto",
    "email": "jpp@chromium.org",
    "time": "Tue Jul 28 16:56:29 2015 -0700"
  },
  "committer": {
    "name": "John Porto",
    "email": "jpp@chromium.org",
    "time": "Tue Jul 28 16:56:29 2015 -0700"
  },
  "message": "Removes references to ah.\n\nAH is a thorn in the flesh for our X86-64 backend. The assembler was\ndesigned to always encode the low 8-bit registers, so %ah would become\n%spl. While it is true we **could** force %spl to always be encoded as\n%ah, that would not work if the instruction has a rex prefix.\n\nThis CL removes references to %ah from TargetX86Base. There used to be\n2 uses of ah in the target lowering:\n\n1) To zero-extend %al before an unsigned div:\n    mov \u003c\u003csrc0\u003e\u003e, %al\n    mov 0, %ah\n    div \u003c\u003csrc1\u003e\u003e\n\nThis pattern has been changed to\n    xor %eax, %eax\n    mov \u003c\u003csrc0\u003e\u003e, %al\n    div \u003c\u003csrc1\u003e\u003e\n\n2) To access the 8-bit remainder for 8-bit division:\n    mov %ah, \u003c\u003cdest\u003e\u003e\n\nThis pattern has been changed to\n    shr $8, %eax\n    mov %al, \u003c\u003cDest\u003e\u003e\n\nBUG\u003d https://code.google.com/p/nativeclient/issues/detail?id\u003d4077\nR\u003dstichnot@chromium.org\n\nReview URL: https://codereview.chromium.org/1260163003.\n",
  "tree_diff": [
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