tree 20c4b8d0ab4773f777e6ee63c865781be94aa0d4
parent d83544638034f5333c94e92188f4000702ddfd8d
author Nicolas Capens <capn@google.com> 1647036677 -0500
committer Nicolas Capens <nicolascapens@google.com> 1647463414 +0000

Improve the precision and performance of highp exp2()

This algorithm is based on the relaxed precision exp2() algorithm, with
a higher degree polynomial and using integer addition to correct the
exponent bias.

It eliminates a shift operation and loading a constant.

The code for the relaxed precision exp2() unit test was refactored for
readability.

Bug: b/169754022
Change-Id: Ie103484f88d7f324a4d6dbd4ba7e9893c5a0e2d7
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/64088
Kokoro-Result: kokoro <noreply+kokoro@google.com>
Tested-by: Nicolas Capens <nicolascapens@google.com>
Reviewed-by: Alexis Hétu <sugoi@google.com>