PR-URL: https://github.com/nodejs/node/pull/47251 Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com> Reviewed-By: Jiawen Geng <technicalcute@gmail.com> Reviewed-By: Rafael Gonzaga <rafael.nunu@hotmail.com> Reviewed-By: Richard Lau <rlau@redhat.com>
28 lines
1.3 KiB
JavaScript
28 lines
1.3 KiB
JavaScript
// Copyright 2023 the V8 project authors. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file.
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//
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// Flags: --maglev --allow-natives-syntax
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function f(x) {
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x++; // Making sure {x} has a Float64 alternative
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let phi = x || 0; // Creating a Phi whose inputs are Smi and Float64. Phi
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// untagging will make this a Float64 phi.
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phi + 1; // Float64 operation with {phi}, which will cause insert a
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// CheckedNumberToFloat64(phi). After phi untagging, the
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// CheckedNumberToFloat64 will be killed, resulting in the addition
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// to take {phi} directly as input.
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phi << 4; // Int operation with {phi}, which will produce a
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// TruncateNumberToInt32(phi). TruncateNumberToInt32 doesn't check
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// if the input is a Number, and call into runtime if necessary to
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// to the truncation, so it can't deopt. After Phi untagging, this
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// should be replaced by a Float64->Int32 truncation
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// (TruncateFloat64ToInt32), which shouldn't deopt either (because
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// we can't replace a non-deopting node by a deopting one).
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}
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%PrepareFunctionForOptimization(f);
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f(1.5);
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%OptimizeMaglevOnNextCall(f);
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f(1.5);
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