tree 7b7906626977bb179d291579cdf0a2e7eec83aa2
parent 55360b11c7da3b19e0c5ae1aa5a7a457cb5e373a
author Mike Klein <mtklein@chromium.org> 1480710063 -0500
committer Skia Commit-Bot <skia-commit-bot@chromium.org> 1480951357 +0000

Manual byte -> float conversion.

This is a follow-up to reviews.skia.org/5540, which did float -> byte.
We use the same trick here exploiting 32768.0f / 0x47000000.

The benefit here is smaller than the other CL, but still measurable.

The exchange here is:
  before: int->float, multiply
  after:  OR, FMA
The cost of an FMA is the same as a multiply, so we're basically just replacing int->float conversion with a bitwise OR.

CQ_INCLUDE_TRYBOTS=skia.primary:Test-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Release-SKNX_NO_SIMD

Change-Id: Ieac2247664afa3ff415aec2b48c21505905bee23
Reviewed-on: https://skia-review.googlesource.com/5542
Reviewed-by: Matt Sarett <msarett@google.com>
Commit-Queue: Mike Klein <mtklein@chromium.org>