chromium/v8/src/compiler/turboshaft/wasm-gc-typed-optimization-reducer.h

// Copyright 2023 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#if !V8_ENABLE_WEBASSEMBLY
#error This header should only be included if WebAssembly is enabled.
#endif  // !V8_ENABLE_WEBASSEMBLY

#ifndef V8_COMPILER_TURBOSHAFT_WASM_GC_TYPED_OPTIMIZATION_REDUCER_H_
#define V8_COMPILER_TURBOSHAFT_WASM_GC_TYPED_OPTIMIZATION_REDUCER_H_

#include "src/compiler/turboshaft/assembler.h"
#include "src/compiler/turboshaft/operations.h"
#include "src/compiler/turboshaft/phase.h"
#include "src/compiler/turboshaft/snapshot-table-opindex.h"
#include "src/compiler/wasm-graph-assembler.h"
#include "src/wasm/wasm-subtyping.h"

namespace v8::internal::compiler::turboshaft {

// The WasmGCTypedOptimizationReducer infers type information based on the input
// graph and reduces type checks and casts based on that information.
//
// This is done in two steps:
// 1) The WasmGCTypeAnalyzer infers the types based on the input graph, e.g.:
//    func (param anyref) (result i32)
//      local.get 0
//      ref.test $MyType
//      if                     // local 0 is known to be (a subtype of) $MyType
//        local.get 0
//        ref.cast $MyType     // the input of this cast is a subtype of $MyType
//                             // it can be removed during reduction
//        struct.get $MyType 0
//        return
//      end                    // local 0 is still anyref
//        i32.const 0
//
// 2) The WasmGCTypedOptimizationReducer reduces the graph to a new graph
//    potentially removing, simplifying (e.g. replacing a cast with a null
//    check) or refining (setting the from type to a more specific type) type
//    operations.

class WasmGCTypeAnalyzer { … };

#include "src/compiler/turboshaft/define-assembler-macros.inc"

template <class Next>
class WasmGCTypedOptimizationReducer : public Next { … };

#include "src/compiler/turboshaft/undef-assembler-macros.inc"

}  // namespace v8::internal::compiler::turboshaft

#endif  // V8_COMPILER_TURBOSHAFT_WASM_GC_TYPED_OPTIMIZATION_REDUCER_H_