Current File : /home/vacivi36/vittasync.vacivitta.com.br/vittasync/node/deps/v8/test/mjsunit/maglev/exceptions.js
// Copyright 2022 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.
//
// Flags: --allow-natives-syntax --maglev
// This examples creates a simple exception handler block where the trampoline
// has an int32 value and needs to convert to a tagged value.
function foo_int32() {
let x = 1;
try {
x = x + x;
throw "Error";
} catch {
return x;
}
}
%PrepareFunctionForOptimization(foo_int32);
assertEquals(foo_int32(), 2);
%OptimizeMaglevOnNextCall(foo_int32);
assertEquals(foo_int32(), 2);
// TODO(leszeks): There is currently no way for this to happen, because all
// Int32 ops are eagerly checked for Smi overflow.
//
// // This examples creates a simple exception handler block where the trampoline
// // has an int32 value that overflows and it needs to create a HeapNumber.
// function foo_int32_overflow(x) {
// try {
// x = x + x;
// throw "Error";
// } catch {
// return x;
// }
// }
// %PrepareFunctionForOptimization(foo_int32_overflow);
// assertEquals(foo_int32_overflow(1), 2);
// %OptimizeMaglevOnNextCall(foo_int32_overflow);
// assertEquals(foo_int32_overflow(0x3FFFFFFF), 0x7FFFFFFE);
// assertTrue(%ActiveTierIsMaglev(foo_int32_overflow));
// // If we call it with a HeapNumber, we deopt before the exception:
// assertEquals(foo_int32_overflow(1.1), 2.2);
// assertTrue(%ActiveTierIsMaglev(foo_int32_overflow));
// This examples creates a simple exception handler block where the trampoline
// has an float64 value and needs to convert to a tagged value.
function foo_float64() {
let x = 1.1;
try {
x = x + x;
throw "Error";
} catch {
return x;
}
}
%PrepareFunctionForOptimization(foo_float64);
assertEquals(foo_float64(), 2.2);
%OptimizeMaglevOnNextCall(foo_float64);
assertEquals(foo_float64(), 2.2);
// Combination of previous examples with a big number of registers.
// This creates a _quite_ large trampoline.
function foo() {
let x = 1;
let y = 1.1;
let a, b, c, d, e, f, g, h;
a = b = c = d = e = f = g = h = 0;
let p, q, r, s, t;
try {
x = x + x;
y = y + y;
p = q = r = s = t = x;
throw "Error";
} catch {
return x + y + a + b + c + d + e + f + g + h
+ p + q + r + s + t;
}
}
%PrepareFunctionForOptimization(foo);
assertEquals(foo(), 14.2);
%OptimizeMaglevOnNextCall(foo);
assertEquals(foo(), 14.2);
Mini Shell