test and fix f16<->f32 conversion stages
This refactors from_half() and to_half() a bit, totally
reimplementing the non-hardware cases to be more clearly correct.
CQ_INCLUDE_TRYBOTS=skia.primary:Test-Android-Clang-PixelC-CPU-TegraX1-arm64-Release-Android,Test-Android-Clang-Ci20-CPU-IngenicJZ4780-mipsel-Release-Android,Test-Android-Clang-Nexus10-CPU-Exynos5250-arm-Release-Android,Test-Mac-Clang-MacMini6.2-CPU-AVX-x86_64-Release,Test-Ubuntu-GCC-GCE-CPU-AVX2-x86-Debug,Test-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Debug
Change-Id: I439463cf90935c5e8fe2369cbcf45e07f3af62c7
Reviewed-on: https://skia-review.googlesource.com/13921
Commit-Queue: Mike Klein <mtklein@chromium.org>
Reviewed-by: Matt Sarett <msarett@google.com>
diff --git a/gn/tests.gni b/gn/tests.gni
index be368f0..5955a32 100644
--- a/gn/tests.gni
+++ b/gn/tests.gni
@@ -63,6 +63,7 @@
"$_tests/EGLImageTest.cpp",
"$_tests/EmptyPathTest.cpp",
"$_tests/ExifTest.cpp",
+ "$_tests/F16StagesTest.cpp",
"$_tests/FillPathTest.cpp",
"$_tests/FitsInTest.cpp",
"$_tests/FlattenableCustomFactory.cpp",