skia2/tests/sksl/shared/OperatorsES3.glsl
John Stiles 353e2c65c9 Prevent comma operator constant-folding or constant-expression-usage.
OpenGL docs specifically insist that the sequence (comma) operator
should not be treated as a constant-expression so that attempts to
declare multidimensional arrays with a comma will fail:
http://screen/vJEpAe9yNmbzZTm

(See "12.43 Sequence operator and constant expressions" in the OpenGL
ES3 documentation or read skia:13311 for details.)

In practice, we don't get much benefit from optimizing away unused
comma-expressions; it improves some synthetic tests, but realistically
this will not help Skia in any real-world scenario. The constant folder
no longer attempts this optimization, and comma-expressions are now
rejected in a constant-expression context.

Change-Id: Ic5dea6ff90e36614b548c1ce89a444e81da944ae
Bug: skia:13311
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/539565
Auto-Submit: John Stiles <johnstiles@google.com>
Reviewed-by: Arman Uguray <armansito@google.com>
Commit-Queue: John Stiles <johnstiles@google.com>
2022-05-11 22:52:24 +00:00

34 lines
837 B
GLSL

out vec4 sk_FragColor;
uniform vec4 colorGreen;
uniform vec4 colorRed;
uniform float unknownInput;
vec4 main() {
float x = 1.0;
float y = 2.0;
int z = 3;
x = (x - x) + ((y * x) * x) * (y - x);
y = (x / y) / x;
z = (((z / 2) % 3 << 4) >> 2) << 1;
bool b = x > 4.0 == x < 2.0 || 2.0 >= unknownInput && y <= x;
bool c = unknownInput > 2.0;
bool d = b ^^ c;
bool e = b && c;
bool f = b || c;
x += 12.0;
x -= 12.0;
x *= (y /= 10.0);
z |= 0;
z &= -1;
z ^= 0;
z >>= 2;
z <<= 4;
z %= 5;
x = float((colorGreen.xy, 6));
y = ((((float(b) * float(c)) * float(d)) * float(e)) * float(f), 6.0);
z = int((colorRed.zw, 6));
ivec2 w = ivec2(~5);
w = ~w;
return (((w.x == 5 && w.y == 5) && x == 6.0) && y == 6.0) && z == 6 ? colorGreen : colorRed;
}