| // Copyright 2015 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 --nostress-opt --turbo |
| // Flags: --nonative-context-specialization |
| |
| var p0 = new Object(); |
| var p1 = new Object(); |
| var p2 = new Object(); |
| |
| // Ensure 1 parameter passed straight-through is handled correctly |
| var count1 = 100000; |
| tailee1 = function() { |
| "use strict"; |
| if (count1-- == 0) { |
| return this; |
| } |
| return %_TailCall(tailee1, this); |
| }; |
| |
| %OptimizeFunctionOnNextCall(tailee1); |
| assertEquals(p0, tailee1.call(p0)); |
| |
| // Ensure 2 parameters passed straight-through trigger a tail call are handled |
| // correctly and don't cause a stack overflow. |
| var count2 = 100000; |
| tailee2 = function(px) { |
| "use strict"; |
| assertEquals(p2, px); |
| assertEquals(p1, this); |
| count2 = ((count2 | 0) - 1) | 0; |
| if ((count2 | 0) === 0) { |
| return this; |
| } |
| return %_TailCall(tailee2, this, px); |
| }; |
| |
| %OptimizeFunctionOnNextCall(tailee2); |
| assertEquals(p1, tailee2.call(p1, p2)); |
| |
| // Ensure swapped 2 parameters trigger a tail call and do the appropriate |
| // parameters swapping |
| var count3 = 999999; |
| tailee3 = function(px) { |
| "use strict"; |
| if (count3-- == 0) { |
| return this; |
| } |
| return %_TailCall(tailee3, px, this); |
| }; |
| |
| %OptimizeFunctionOnNextCall(tailee3); |
| assertEquals(p2, tailee3.call(p1, p2)); |
| |
| // Ensure too many parameters defeats the tail call optimization (currently |
| // unsupported). |
| var count4 = 1000000; |
| tailee4 = function(px) { |
| "use strict"; |
| if (count4-- == 0) { |
| return this; |
| } |
| return %_TailCall(tailee4, this, px, undefined); |
| }; |
| |
| %OptimizeFunctionOnNextCall(tailee4); |
| assertThrows(function() { tailee4.call(p1, p2); }); |
| |
| // Ensure that calling the arguments adapter defeats the tail call optimization. |
| var count5 = 1000000; |
| tailee5 = function(px) { |
| "use strict"; |
| if (count5-- == 0) { |
| return this; |
| } |
| return %_TailCall(tailee5, this); |
| }; |
| |
| %OptimizeFunctionOnNextCall(tailee5); |
| assertThrows(function() { tailee5.call(p1, p2); }); |
| |
| // Ensure tail calls with fewer stack parameters properly re-arranges the stack. |
| tailee6 = function(px) { |
| return px; |
| } |
| |
| tailee7 = function(px, py, pz, pa, pb, pc) { |
| "use strict"; |
| return %_TailCall(tailee6, this, pc); |
| }; |
| |
| %OptimizeFunctionOnNextCall(tailee6); |
| %OptimizeFunctionOnNextCall(tailee7); |
| assertEquals(110, tailee7.call(null, 15, 16, 17, 18, 0, 110)); |
| |
| tailee8 = function(px, py, pz, pa, pb) { |
| return pb + pz + px; |
| } |
| |
| tailee9 = function(px, py, pz, pa, pb, pc) { |
| "use strict"; |
| return %_TailCall(tailee8, this, pb, py, px, pa, pz); |
| }; |
| |
| %OptimizeFunctionOnNextCall(tailee8); |
| %OptimizeFunctionOnNextCall(tailee9); |
| assertEquals(32, tailee9.call(null, 15, 16, 17, 18, 0, 110)); |