blob: 242b9546a71ba9b58b64f0830ecbcacf77ebf176 [file] [log] [blame]
/*
* 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/SkSLConstructorCompoundCast.h"
#include "src/sksl/ir/SkSLConstructor.h"
#include "src/sksl/ir/SkSLConstructorCompound.h"
#include "src/sksl/ir/SkSLConstructorDiagonalMatrix.h"
#include "src/sksl/ir/SkSLConstructorScalarCast.h"
#include "src/sksl/ir/SkSLConstructorSplat.h"
namespace SkSL {
static std::unique_ptr<Expression> cast_constant_composite(const Context& context,
const Type& destType,
std::unique_ptr<Expression> constCtor) {
const Type& scalarType = destType.componentType();
if (constCtor->is<ConstructorSplat>()) {
// This is a composite-cast of a splat containing a constant value, e.g. `half4(7)`. We can
// replace it with a splat of a different type, e.g. `int4(7)`.
ConstructorSplat& splat = constCtor->as<ConstructorSplat>();
return ConstructorSplat::Make(
context, constCtor->fOffset, destType,
ConstructorScalarCast::Make(context, constCtor->fOffset, scalarType,
std::move(splat.argument())));
}
if (constCtor->is<ConstructorDiagonalMatrix>()) {
// This is a composite-cast of a diagonal matrix, e.g. `float3x3(2)`. We can
// replace it with a splat of a different type, e.g. `half3x3(2)`.
ConstructorDiagonalMatrix& splat = constCtor->as<ConstructorDiagonalMatrix>();
return ConstructorDiagonalMatrix::Make(
context, constCtor->fOffset, destType,
ConstructorScalarCast::Make(context, constCtor->fOffset, scalarType,
std::move(splat.argument())));
}
// Create a composite Constructor(literal, ...) which typecasts each argument inside.
auto inputArgs = constCtor->asAnyConstructor().argumentSpan();
ExpressionArray typecastArgs;
typecastArgs.reserve_back(inputArgs.size());
for (std::unique_ptr<Expression>& arg : inputArgs) {
const Type& argType = arg->type();
if (argType.isScalar()) {
int offset = arg->fOffset;
typecastArgs.push_back(ConstructorScalarCast::Make(context, offset, scalarType,
std::move(arg)));
} else {
// Convert inner constant-composites recursively.
SkASSERT(argType.isVector());
typecastArgs.push_back(cast_constant_composite(
context,
scalarType.toCompound(context, /*columns=*/argType.columns(), /*rows=*/1),
std::move(arg)));
}
}
return ConstructorCompound::Make(context, constCtor->fOffset, destType,
std::move(typecastArgs));
}
std::unique_ptr<Expression> ConstructorCompoundCast::Make(const Context& context,
int offset,
const Type& type,
std::unique_ptr<Expression> arg) {
// Only vectors or matrices of the same dimensions are allowed.
SkASSERT(type.isVector() || type.isMatrix());
SkASSERT(arg->type().isVector() == type.isVector());
SkASSERT(arg->type().isMatrix() == type.isMatrix());
SkASSERT(type.columns() == arg->type().columns());
SkASSERT(type.rows() == arg->type().rows());
// If this is a no-op cast, return the expression as-is.
if (type == arg->type()) {
return arg;
}
// We can cast a vector of compile-time constants at compile-time.
if (arg->isCompileTimeConstant()) {
return cast_constant_composite(context, type, std::move(arg));
}
return std::make_unique<ConstructorCompoundCast>(offset, type, std::move(arg));
}
} // namespace SkSL