v8/test/mjsunit/generated-transition-stub.js

// Copyright 2013 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

%NeverOptimizeFunction(test);
function test() {

  const iteration_count = 1;

  function transition1(a, i, v) {
    a[i] = v;
  }

  //
  // Test PACKED SMI -> PACKED DOUBLE
  //

  %PrepareFunctionForOptimization(transition1);
  const a1 = [0, 1, 2, 3, 4];
  transition1(a1, 0, 2.5);
  const a2 = [0, 1, 2, 3, 4];
  transition1(a2, 0, 2.5);
  assertFalse(%HasHoleyElements(a2));
  %OptimizeFunctionOnNextCall(transition1);

  const a3 = [0, 1, 2, 3, 4];
  assertTrue(%HasSmiElements(a3));
  transition1(a3, 0, 2.5);
  assertFalse(%HasHoleyElements(a3));
  assertEquals(4, a3[4]);
  assertEquals(2.5, a3[0]);

  // Test handling of hole.
  const a4 = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9];
  a4.length = 7;
  assertTrue(%HasSmiElements(a4));
  transition1(a4, 0, 2.5);
  assertFalse(%HasHoleyElements(a4));
  assertEquals(2.5, a4[0]);
  assertEquals(undefined, a4[8]);

  // Large array should deopt to runtimea
  for (j = 0; j < iteration_count; ++j) {
    const a5 = new Array();
    for (i = 0; i < 0x40000; ++i) {
      a5[i] = 0;
    }
    assertTrue(%HasSmiElements(a5) || %HasDoubleElements(a5));
    transition1(a5, 0, 2.5);
    assertEquals(2.5, a5[0]);
  }

  //
  // Test HOLEY SMI -> HOLEY DOUBLE
  //

  function transition2(a, i, v) {
    a[i] = v;
  }

  %PrepareFunctionForOptimization(transition2);
  const b1 = [0, 1, 2, , 4];
  transition2(b1, 0, 2.5);
  const b2 = [0, 1, 2, , 4];
  transition2(b2, 0, 2.5);
  assertTrue(%HasHoleyElements(b2));
  %OptimizeFunctionOnNextCall(transition2);

  const b3 = [0, 1, 2, , 4];
  assertTrue(%HasSmiElements(b3));
  assertTrue(%HasHoleyElements(b3));
  transition2(b3, 0, 2.5);
  assertTrue(%HasHoleyElements(b3));
  assertEquals(4, b3[4]);
  assertEquals(2.5, b3[0]);

  // Large array should deopt to runtime
  for (j = 0; j < iteration_count; ++j) {
    const b4 = [0, ,0];
    for (i = 3; i < 0x40000; ++i) {
      b4[i] = 0;
    }
    assertTrue(%HasSmiElements(b4));
    transition2(b4, 0, 2.5);
    assertEquals(2.5, b4[0]);
  }

  //
  // Test PACKED DOUBLE -> PACKED OBJECT
  //

  function transition3(a, i, v) {
    a[i] = v;
  }

  %PrepareFunctionForOptimization(transition3);
  const c1 = [0, 1, 2, 3.5, 4];
  transition3(c1, 0, new Object());
  const c2 = [0, 1, 2, 3.5, 4];
  transition3(c2, 0, new Object());
  assertTrue(%HasObjectElements(c2));
  assertTrue(!%HasHoleyElements(c2));
  %OptimizeFunctionOnNextCall(transition3);

  const c3 = [0, 1, 2, 3.5, 4];
  assertTrue(%HasDoubleElements(c3));
  assertTrue(!%HasHoleyElements(c3));
  transition3(c3, 0, new Array());
  assertTrue(!%HasHoleyElements(c3));
  assertTrue(%HasObjectElements(c3));
  assertEquals(4, c3[4]);
  assertEquals(0, c3[0].length);

  // Large array under the deopt threshold should be able to trigger GC without
  // causing crashes.
  for (j = 0; j < iteration_count; ++j) {
    const c4 = [0, 2.5, 0];
    for (i = 3; i < 0xa000; ++i) {
      c4[i] = 0;
    }
    assertTrue(%HasDoubleElements(c4));
    assertTrue(!%HasHoleyElements(c4));
    transition3(c4, 0, new Array(5));
    assertTrue(!%HasHoleyElements(c4));
    assertTrue(%HasObjectElements(c4));
    assertEquals(5, c4[0].length);
  }

  // Large array should deopt to runtime
  for (j = 0; j < iteration_count; ++j) {
    const c5 = [0, 2.5, 0];
    for (i = 3; i < 0x40000; ++i) {
      c5[i] = 0;
    }
    assertTrue(%HasDoubleElements(c5));
    assertTrue(!%HasHoleyElements(c5));
    transition3(c5, 0, new Array(5));
    assertTrue(!%HasHoleyElements(c5));
    assertTrue(%HasObjectElements(c5));
    assertEquals(5, c5[0].length);
  }

  //
  // Test HOLEY DOUBLE -> HOLEY OBJECT
  //

  function transition4(a, i, v) {
      a[i] = v;
  }

  %PrepareFunctionForOptimization(transition4);
  const d1 = [0, 1, , 3.5, 4];
  transition4(d1, 0, new Object());
  const d2 = [0, 1, , 3.5, 4];
  transition4(d2, 0, new Object());
  assertTrue(%HasObjectElements(d2));
  assertTrue(%HasHoleyElements(d2));
  %OptimizeFunctionOnNextCall(transition4);

  const d3 = [0, 1, , 3.5, 4];
  assertTrue(%HasDoubleElements(d3));
  assertTrue(%HasHoleyElements(d3));
  transition4(d3, 0, new Array());
  assertTrue(%HasHoleyElements(d3));
  assertTrue(%HasObjectElements(d3));
  assertEquals(4, d3[4]);
  assertEquals(0, d3[0].length);

  // Large array under the deopt threshold should be able to trigger GC without
  // causing crashes.
  for (j = 0; j < iteration_count; ++j) {
    const d4 = [, 2.5, ,];
    for (i = 3; i < 0xa000; ++i) {
      d4[i] = 0;
    }
    assertTrue(%HasDoubleElements(d4));
    assertTrue(%HasHoleyElements(d4));
    transition4(d4, 0, new Array(5));
    assertTrue(%HasHoleyElements(d4));
    assertTrue(%HasObjectElements(d4));
    assertEquals(5, d4[0].length);
    assertEquals(undefined, d4[2]);
  }

  // Large array should deopt to runtime
  for (j = 0; j < iteration_count; ++j) {
    const d5 = [, 2.5, ,];
    for (i = 3; i < 0x40000; ++i) {
      d5[i] = 0;
    }
    assertTrue(%HasDoubleElements(d5));
    assertTrue(%HasHoleyElements(d5));
    transition4(d5, 0, new Array(5));
    assertTrue(%HasHoleyElements(d5));
    assertTrue(%HasObjectElements(d5));
    assertEquals(5, d5[0].length);
    assertEquals(undefined, d5[2]);
  }

}
test();