// 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: --expose-debug-as debug // This test ensures that IC learning doesn't interfere with stepping into // property accessor. f1()'s ICs are allowed to learn to a monomorphic state, // and the breakpoints flooding get() are allowed to expire, then we ensure // that we can step into get() again later (when k == 1). function f1() { for (var k = 0; k < 2; k++) { // Break 1 var v10 = 0; // Line 2 for (var i = 0; i < 10; i++) { // Line 3 var v12 = o.slappy; // Line 4 var v13 = 3 // Line 5 } // Line 6 print("break here"); // Break 3 } // Line 8 print("exiting f1"); // Line 9 (dummy break) } function get() { var g0 = 0; // Break 2 var g1 = 1; return 3; } var o = {}; Object.defineProperty(o, "slappy", { get : get }); Debug = debug.Debug; var break_count = 0 var exception = null; var bp_f1_line7; var bp_f1_line9; function listener(event, exec_state, event_data, data) { if (event != Debug.DebugEvent.Break) return; try { var line = exec_state.frame(0).sourceLineText(); print(line); var match = line.match(/\/\/ Break (\d+)$/); assertEquals(2, match.length); var match_value = parseInt(match[1]); if (break_count >= 0 && break_count < 2) { // 0, 1: Keep stepping through frames. assertEquals(break_count, match_value); exec_state.prepareStep(Debug.StepAction.StepFrame, 1); } else if (break_count === 2) { // 2: let the code run to a breakpoint we set. The load should // go monomorphic. assertEquals(break_count, match_value); } else if (break_count === 3) { // 3: back to frame stepping. Does the monomorphic slappy accessor // call still have the ability to break like before? assertEquals(break_count, match_value); Debug.clearBreakPoint(bp_f1_line7); exec_state.prepareStep(Debug.StepAction.StepFrame, 1); } else { assertEquals(4, break_count); assertEquals(2, match_value); // Apparently we can still stop in the accessor even though we cleared // breakpoints earlier and there was a monomorphic step. // Allow running to completion now. Debug.clearBreakPoint(bp_f1_line9); } break_count++; } catch (e) { print(e + e.stack); exception = e; } } for (var j = 1; j < 3; j++) { break_count = 0; Debug.setListener(listener); // Breakpoints are added here rather than in the listener because their // addition causes a full (clearing) gc that clears type feedback when we // want to let it build up. Also, bp_f1_line9 is set simply because if we // handled then deleted bp_f1_line7, then the debugger clears DebugInfo from // f1 while we are still using it, again, resetting type feedback which is // undesirable. bp_f1_line7 = Debug.setBreakPoint(f1, 7); bp_f1_line9 = Debug.setBreakPoint(f1, 9); debugger; // Break 0 f1(); Debug.setListener(null); assertTrue(break_count === 5); } assertNull(exception);