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  1. 14 May, 2018 1 commit
    • Benedikt Meurer's avatar
      Revert "[turbofan][x64] Reduce compare-zero followed by flags-setting binop" · b2dc9468
      Benedikt Meurer authored 
      This reverts commit 42334363.

Reason for revert: Seems to lead to floating point exceptions, i.e. with this code:

```js
__v_0 = 'x'.repeat();
var __f_1 = (function __f_0() {
  "use asm";
  function __f_1(__v_5, __v_0) {
    __v_5 = __v_5 | 0;
    __v_0 = __v_0 | 0;
    return ((__v_5 >>> 4) % (__v_0 >>> 1073741824)) | -1073741825;
  }
  return { __f_1: __f_1 };
})().__f_1;
  for (var __v_5 = 0; __v_5 < 4294967296; __v_5 += 3999773) {__v_5 % __v_0 | 0, __f_1();
  }
```

Running with UBSan via `d8-ubsan-vptr-linux-release-v8-component-53134/d8 --random-seed=54105979 --disable-in-process-stack-traces --stress-marking=100 fuzz-02382.js`

Original change's description:
> [turbofan][x64] Reduce compare-zero followed by flags-setting binop
> 
> On IA architecture, arithmetic and shifting operations set the flags
> according to the computation result.
> 
>     subl rsi,0x1
>     REX.W movq rbx,[rbx+0x17]
>     cmpl rsi, 0                       <-- TO BE REDUCED
>     jnz 0x3f54d2dcef0
> ==>
>     REX.W movq rbx,[rbx+0x17]
>     subl rsi,0x1
>     jnz 0x3f54d2dcef0
> &
>     orl rdx,rbx
>     cmpl rdx,0x0                      <-- TO BE REDUCED
>     jnz 0x3f54d22b0f5
> ==>
>     orl rdx,rbx
>     jnz 0x3f54d22b0f5
> 
> Change-Id: If69c023712212ad7b9fa8b29f4b98274f7885e35
> Reviewed-on: https://chromium-review.googlesource.com/1051445
> Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
> Commit-Queue: Kanghua Yu <kanghua.yu@intel.com>
> Cr-Commit-Position: refs/heads/master@{#53118}

TBR=bmeurer@chromium.org,kanghua.yu@intel.com

# Not skipping CQ checks because original CL landed > 1 day ago.

Change-Id: I8a177b9268a2fefcd6877d8f33134e7e0c980926
Reviewed-on: https://chromium-review.googlesource.com/1057067Reviewed-by: 's avatarBenedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53137}
      b2dc9468
  3. 13 May, 2018 2 commits
  5. 11 May, 2018 17 commits
  7. 10 May, 2018 2 commits
  9. 09 May, 2018 18 commits