blob: d0783b8d95a526da9f49ccb2895c4a8091ad34af [file] [log] [blame]
// Copyright 2022 The Dawn & Tint Authors
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice, this
// list of conditions and the following disclaimer.
//
// 2. Redistributions in binary form must reproduce the above copyright notice,
// this list of conditions and the following disclaimer in the documentation
// and/or other materials provided with the distribution.
//
// 3. Neither the name of the copyright holder nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
// OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#ifndef SRC_TINT_LANG_CORE_IR_SWITCH_H_
#define SRC_TINT_LANG_CORE_IR_SWITCH_H_
#include <string>
#include <utility>
#include "src/tint/lang/core/ir/control_instruction.h"
#include "src/tint/utils/containers/const_propagating_ptr.h"
// Forward declarations
namespace tint::core::ir {
class Constant;
class MultiInBlock;
} // namespace tint::core::ir
namespace tint::core::ir {
/// Switch instruction.
///
/// ```
/// in
/// ┃
/// ╌╌╌╌╌╌╌╌┲━━━━━━━━━━━━━━╋━━━━━━━━━━━━━━┱╌╌╌╌╌╌╌╌
/// ▼ ▼ ▼
/// ┌────────┐ ┌────────┐ ┌────────┐
/// │ Case A │ │ Case B │ │ Case C │
/// └────────┘ └────────┘ └────────┘
/// ExitSwitch ┃ ExitSwitch ┃ ExitSwitch ┃
/// ┃ ┃ ┃
/// ╌╌╌╌╌╌╌╌┺━━━━━━━━━━━━━━╋━━━━━━━━━━━━━━┹╌╌╌╌╌╌╌╌
/// ┃
/// ▼
/// out
/// ```
class Switch final : public Castable<Switch, ControlInstruction> {
public:
/// The offset in Operands() for the condition
static constexpr size_t kConditionOperandOffset = 0;
/// A case selector
struct CaseSelector {
/// @returns true if this is a default selector
bool IsDefault() const { return val == nullptr; }
/// The selector value, or nullptr if this is the default selector
ConstPropagatingPtr<Constant> val;
};
/// A case label in the struct
struct Case {
/// The case selector for this node
Vector<CaseSelector, 4> selectors;
/// The case block.
ConstPropagatingPtr<ir::Block> block;
};
/// Constructor (no results, no operands, no cases)
Switch();
/// Constructor
/// @param cond the condition
explicit Switch(Value* cond);
~Switch() override;
/// @copydoc Instruction::Clone()
Switch* Clone(CloneContext& ctx) override;
/// @copydoc ControlInstruction::ForeachBlock
void ForeachBlock(const std::function<void(ir::Block*)>& cb) override;
/// @returns the switch cases
Vector<Case, 4>& Cases() { return cases_; }
/// @returns the switch cases
VectorRef<Case> Cases() const { return cases_; }
/// @returns the condition
Value* Condition() { return operands_[kConditionOperandOffset]; }
/// @returns the condition
const Value* Condition() const { return operands_[kConditionOperandOffset]; }
/// @returns the friendly name for the instruction
std::string FriendlyName() const override { return "switch"; }
private:
Vector<Case, 4> cases_;
};
} // namespace tint::core::ir
#endif // SRC_TINT_LANG_CORE_IR_SWITCH_H_