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// 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.
d8.file.execute('test/mjsunit/wasm/wasm-module-builder.js');
let builder = new WasmModuleBuilder();
builder.addMemory(1, 1, false);
builder.addDataSegment(0, [0x78, 0x56, 0x34, 0x12]);
let spiller = builder.addFunction('spiller', kSig_v_v).addBody([]);
builder.addFunction('main', kSig_l_v)
.exportFunc()
.addLocals(kWasmI64, 1)
.addBody([
// Initialize {var0} to 0x12345678 via a zero-extended 32-bit load.
kExprI32Const, 0,
kExprI64LoadMem32U, 2, 0,
kExprLocalSet, 0,
kExprCallFunction, spiller.index,
// The observable effect of this loop is that {var0} is left-shifted
// until it ends in 0x..000000. The details are specifically crafted
// to recreate a particular pattern of spill slot moves.
kExprLoop, kWasmVoid,
kExprI32Const, 0,
kExprI32LoadMem, 2, 0,
kExprI32Eqz,
// This block is never taken; it only serves to influence register
// allocator choices.
kExprIf, kWasmVoid,
kExprLocalGet, 0,
kExprI64Const, 1,
kExprI64And,
kExprLocalSet, 0,
kExprEnd, // if
kExprLocalGet, 0,
kExprI64Const, 1,
kExprI64And,
kExprI64Eqz,
// This block is always taken; it is conditional in order to influence
// register allocator choices.
kExprIf, kWasmVoid,
kExprLocalGet, 0,
kExprI64Const, 8,
kExprI64Shl,
kExprLocalSet, 0,
kExprEnd, // if
kExprBlock, kWasmVoid,
kExprLocalGet, 0,
...wasmI64Const(0xFFFFFF),
kExprI64And,
kExprI64Eqz,
kExprI32Eqz,
kExprCallFunction, spiller.index,
kExprBrIf, 1,
kExprEnd, // block
kExprCallFunction, spiller.index,
kExprEnd, // loop
kExprLocalGet, 0,
]);
let instance = builder.instantiate();
assertEquals("12345678000000", instance.exports.main().toString(16));
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