diff options
Diffstat (limited to 'gfx/skia/skia/src/sksl/ir/SkSLConstructorArrayCast.cpp')
-rw-r--r-- | gfx/skia/skia/src/sksl/ir/SkSLConstructorArrayCast.cpp | 73 |
1 files changed, 73 insertions, 0 deletions
diff --git a/gfx/skia/skia/src/sksl/ir/SkSLConstructorArrayCast.cpp b/gfx/skia/skia/src/sksl/ir/SkSLConstructorArrayCast.cpp new file mode 100644 index 0000000000..a5f9039eb0 --- /dev/null +++ b/gfx/skia/skia/src/sksl/ir/SkSLConstructorArrayCast.cpp @@ -0,0 +1,73 @@ +/* + * Copyright 2021 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/ir/SkSLConstructorArrayCast.h" + +#include "include/core/SkSpan.h" +#include "include/core/SkTypes.h" +#include "include/private/SkSLDefines.h" +#include "src/sksl/SkSLAnalysis.h" +#include "src/sksl/SkSLConstantFolder.h" +#include "src/sksl/ir/SkSLConstructorArray.h" +#include "src/sksl/ir/SkSLConstructorCompoundCast.h" +#include "src/sksl/ir/SkSLConstructorScalarCast.h" +#include "src/sksl/ir/SkSLType.h" + +namespace SkSL { + +static std::unique_ptr<Expression> cast_constant_array(const Context& context, + Position pos, + const Type& destType, + std::unique_ptr<Expression> constCtor) { + const Type& scalarType = destType.componentType(); + + // Create a ConstructorArray(...) which typecasts each argument inside. + auto inputArgs = constCtor->as<ConstructorArray>().argumentSpan(); + ExpressionArray typecastArgs; + typecastArgs.reserve_back(inputArgs.size()); + for (std::unique_ptr<Expression>& arg : inputArgs) { + Position argPos = arg->fPosition; + if (arg->type().isScalar()) { + typecastArgs.push_back(ConstructorScalarCast::Make(context, argPos, scalarType, + std::move(arg))); + } else { + typecastArgs.push_back(ConstructorCompoundCast::Make(context, argPos, scalarType, + std::move(arg))); + } + } + + return ConstructorArray::Make(context, pos, destType, std::move(typecastArgs)); +} + +std::unique_ptr<Expression> ConstructorArrayCast::Make(const Context& context, + Position pos, + const Type& type, + std::unique_ptr<Expression> arg) { + // Only arrays of the same size are allowed. + SkASSERT(type.isArray()); + SkASSERT(type.isAllowedInES2(context)); + SkASSERT(arg->type().isArray()); + SkASSERT(type.columns() == arg->type().columns()); + + // If this is a no-op cast, return the expression as-is. + if (type.matches(arg->type())) { + arg->fPosition = pos; + return arg; + } + + // Look up the value of constant variables. This allows constant-expressions like `myArray` to + // be replaced with the compile-time constant `int[2](0, 1)`. + arg = ConstantFolder::MakeConstantValueForVariable(pos, std::move(arg)); + + // We can cast a vector of compile-time constants at compile-time. + if (Analysis::IsCompileTimeConstant(*arg)) { + return cast_constant_array(context, pos, type, std::move(arg)); + } + return std::make_unique<ConstructorArrayCast>(pos, type, std::move(arg)); +} + +} // namespace SkSL |