skia2/tests/sksl/shared/WhileLoopControlFlow.glsl
John Stiles 4d6310ab20 Support half4 return values from main() in the SPIR-V code generator.
This creates a helper function, _entrypoint, which invokes main() and
assigns its result into sk_FragColor. We also make sure to prevent
sk_FragColor from being dead-stripped from the code during IR
generation.

At present this is useful for allowing our SkSL test shaders to compile.

Change-Id: I2d7fab0e1959a77778ffdb18ca569e869bcaeece
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/358525
Commit-Queue: John Stiles <johnstiles@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
2021-01-27 02:46:03 +00:00

16 lines
280 B
GLSL

out vec4 sk_FragColor;
vec4 main() {
vec4 x = vec4(1.0, 1.0, 1.0, 1.0);
while (x.w == 1.0) {
x.x -= 0.25;
if (x.x <= 0.0) break;
}
while (x.z > 0.0) {
x.z -= 0.25;
if (x.w == 1.0) continue;
x.y = 0.0;
}
return x;
}