skia2/tests/sksl/blend/golden/BlendSoftLight.metal
John Stiles 345d72124d Eliminate inliner temporary variables for functions with a single exit.
When we determine that a function only contains a single return
statement, there is no need to create a temporary variable and store the
result expression into a variable. Instead, we can directly replace the
function-call expression with the return-statement's expression.

This dramatically simplifies the final optimized output from chains of
very simple inlined functions, which is a very common pattern for trees
of Skia fragment processors.

Change-Id: I6789064a321daf43db2e1cef4915f25ed74d6131
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/344665
Commit-Queue: John Stiles <johnstiles@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
Auto-Submit: John Stiles <johnstiles@google.com>
2020-12-16 17:26:06 +00:00

37 lines
1.3 KiB
Metal

#include <metal_stdlib>
#include <simd/simd.h>
using namespace metal;
struct Inputs {
float4 src;
float4 dst;
};
struct Outputs {
float4 sk_FragColor [[color(0)]];
};
float _soft_light_component(float2 s, float2 d) {
if (2.0 * s.x <= s.y) {
float _8_n = (d.x * d.x) * (s.y - 2.0 * s.x);
return (_8_n / d.y + (1.0 - d.y) * s.x) + d.x * ((-s.y + 2.0 * s.x) + 1.0);
} else if (4.0 * d.x <= d.y) {
float DSqd = d.x * d.x;
float DCub = DSqd * d.x;
float DaSqd = d.y * d.y;
float DaCub = DaSqd * d.y;
float _10_n = ((DaSqd * (s.x - d.x * ((3.0 * s.y - 6.0 * s.x) - 1.0)) + ((12.0 * d.y) * DSqd) * (s.y - 2.0 * s.x)) - (16.0 * DCub) * (s.y - 2.0 * s.x)) - DaCub * s.x;
return _10_n / DaSqd;
} else {
return ((d.x * ((s.y - 2.0 * s.x) + 1.0) + s.x) - sqrt(d.y * d.x) * (s.y - 2.0 * s.x)) - d.y * s.x;
}
}
fragment Outputs fragmentMain(Inputs _in [[stage_in]], bool _frontFacing [[front_facing]], float4 _fragCoord [[position]]) {
Outputs _outputStruct;
thread Outputs* _out = &_outputStruct;
_out->sk_FragColor = _in.dst.w == 0.0 ? _in.src : float4(_soft_light_component(_in.src.xw, _in.dst.xw), _soft_light_component(_in.src.yw, _in.dst.yw), _soft_light_component(_in.src.zw, _in.dst.zw), _in.src.w + (1.0 - _in.src.w) * _in.dst.w);
return *_out;
}