simple-deopt.js revision b0fe1620dcb4135ac3ab2d66ff93072373911299 
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27
28function f(x) {
29  return ~x;
30}
31
32f(42);
33assertEquals(~12, f(12.45));
34assertEquals(~42, f(42.87));
35
36
37var a = 1, b = 2, c = 4, d = 8;
38function g() {
39  return a | (b | (c | d));
40}
41
42g();
43c = "16";
44assertEquals(1 | 2 | 16 | 8, g());
45
46
47// Test deopt when global function changes.
48function h() {
49  return g();
50}
51assertEquals(1 | 2 | 16 | 8, h());
52g = function() { return 42; };
53assertEquals(42, h());
54
55
56// Test deopt when map changes.
57var obj = {};
58obj.g = g;
59function k(o) {
60  return o.g();
61}
62for (var i = 0; i < 1000000; i++) k(obj);
63assertEquals(42, k(obj));
64assertEquals(87, k({g: function() { return 87; }}));
65
66
67// Test deopt with assignments to parameters.
68function p(x,y) {
69  x = 42;
70  y = 1;
71  y = y << "0";
72  return x | y;
73}
74assertEquals(43, p(0,0));
75
76
77// Test deopt with literals on the expression stack.
78function LiteralToStack(x) {
79  return 'lit[' + (x + ']');
80}
81
82assertEquals('lit[-87]', LiteralToStack(-87));
83assertEquals('lit[0]', LiteralToStack(0));
84assertEquals('lit[42]', LiteralToStack(42));
85
86
87// Test deopt before call.
88var str = "abc";
89var r;
90function CallCharAt(n) { return str.charAt(n); }
91for (var i = 0; i < 1000000; i++) {
92  r = CallCharAt(0);
93}
94assertEquals("a", r);
95
96
97// Test of deopt in presence of spilling.
98function add4(a,b,c,d) {
99  return a+b+c+d;
100}
101assertEquals(0x40000003, add4(1,1,2,0x3fffffff));
102