skia2/tests/SkSLGLSLTestbed.cpp

/*
 * Copyright 2020 Google LLC
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#include "src/sksl/SkSLCompiler.h"

#include "tests/Test.h"

// Note that the optimizer will aggressively kill dead code and substitute constants in place of
// variables, so we have to jump through a few hoops to ensure that the code in these tests has the
// necessary side-effects to remain live. In some cases we rely on the optimizer not (yet) being
// smart enough to optimize around certain constructs; as the optimizer gets smarter it will
// undoubtedly end up breaking some of these tests. That is a good thing, as long as the new code is
// equivalent!

static void test(skiatest::Reporter* r, const SkSL::Program::Settings& settings, const char* src,
                 SkSL::Program::Inputs* inputs,
                 SkSL::Program::Kind kind = SkSL::Program::kFragment_Kind) {
    SkSL::Compiler compiler;
    SkSL::String output;
    std::unique_ptr<SkSL::Program> program = compiler.convertProgram(kind, SkSL::String(src),
                                                                     settings);
    if (!program) {
        SkDebugf("Unexpected error compiling %s\n%s", src, compiler.errorText().c_str());
        REPORTER_ASSERT(r, program);
    } else {
        *inputs = program->fInputs;
        REPORTER_ASSERT(r, compiler.toGLSL(*program, &output));
        REPORTER_ASSERT(r, output != "");
        //SkDebugf("GLSL output:\n\n%s", output.c_str());
    }
}

static void test(skiatest::Reporter* r, const GrShaderCaps& caps, const char* src,
                 SkSL::Program::Kind kind = SkSL::Program::kFragment_Kind) {
    SkSL::Program::Settings settings;
    settings.fCaps = &caps;
    SkSL::Program::Inputs inputs;
    test(r, settings, src, &inputs, kind);
}

DEF_TEST(SkSLGLSLTestbed, r) {
    // Add in your SkSL here.
    test(r,
         *SkSL::ShaderCapsFactory::Default(),
         R"__SkSL__(
             void main() {
                 sk_FragColor = half4(0);
             }
         )__SkSL__");
}