/js/src/methodjit/MethodJIT-inl.h

  1/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
  2 * vim: set ts=4 sw=4 et tw=99:
  3 *
  4 * ***** BEGIN LICENSE BLOCK *****
  5 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
  6 *
  7 * The contents of this file are subject to the Mozilla Public License Version
  8 * 1.1 (the "License"); you may not use this file except in compliance with
  9 * the License. You may obtain a copy of the License at
 10 * http://www.mozilla.org/MPL/
 11 *
 12 * Software distributed under the License is distributed on an "AS IS" basis,
 13 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 14 * for the specific language governing rights and limitations under the
 15 * License.
 16 *
 17 * The Original Code is Mozilla SpiderMonkey JavaScript 1.9 code, released
 18 * May 28, 2008.
 19 *
 20 * The Initial Developer of the Original Code is
 21 *   Brendan Eich <brendan@mozilla.org>
 22 *
 23 * Contributor(s):
 24 *   David Anderson <danderson@mozilla.com>
 25 *   David Mandelin <dmandelin@mozilla.com>
 26 *
 27 * Alternatively, the contents of this file may be used under the terms of
 28 * either of the GNU General Public License Version 2 or later (the "GPL"),
 29 * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 30 * in which case the provisions of the GPL or the LGPL are applicable instead
 31 * of those above. If you wish to allow use of your version of this file only
 32 * under the terms of either the GPL or the LGPL, and not to allow others to
 33 * use your version of this file under the terms of the MPL, indicate your
 34 * decision by deleting the provisions above and replace them with the notice
 35 * and other provisions required by the GPL or the LGPL. If you do not delete
 36 * the provisions above, a recipient may use your version of this file under
 37 * the terms of any one of the MPL, the GPL or the LGPL.
 38 *
 39 * ***** END LICENSE BLOCK ***** */
 40
 41#if !defined jsjaeger_methodjit_inl_h__ && defined JS_METHODJIT
 42#define jsjaeger_methodjit_inl_h__
 43
 44namespace js {
 45namespace mjit {
 46
 47enum CompileRequest
 48{
 49    CompileRequest_Interpreter,
 50    CompileRequest_JIT
 51};
 52
 53/*
 54 * We wait before compiling a function with Type Inference to allow more gathering 
 55 * of type information and less recompilation.
 56 */
 57static const size_t USES_BEFORE_COMPILE = 16;
 58static const size_t INFER_USES_BEFORE_COMPILE = 40;
 59
 60static inline CompileStatus
 61CanMethodJIT(JSContext *cx, JSScript *script, bool construct, CompileRequest request)
 62{
 63    if (!cx->methodJitEnabled)
 64        return Compile_Abort;
 65    JITScriptStatus status = script->getJITStatus(construct);
 66    if (status == JITScript_Invalid)
 67        return Compile_Abort;
 68    if (request == CompileRequest_Interpreter && status == JITScript_None &&
 69        !cx->hasRunOption(JSOPTION_METHODJIT_ALWAYS) &&
 70        (cx->typeInferenceEnabled()
 71         ? script->incUseCount() <= INFER_USES_BEFORE_COMPILE
 72         : script->incUseCount() <= USES_BEFORE_COMPILE))
 73    {
 74        return Compile_Skipped;
 75    }
 76    if (status == JITScript_None)
 77        return TryCompile(cx, script, construct);
 78    return Compile_Okay;
 79}
 80
 81/*
 82 * Called from a backedge in the interpreter to decide if we should transition to the
 83 * methodjit. If so, we compile the given function.
 84 */
 85static inline CompileStatus
 86CanMethodJITAtBranch(JSContext *cx, JSScript *script, StackFrame *fp, jsbytecode *pc)
 87{
 88    if (!cx->methodJitEnabled)
 89        return Compile_Abort;
 90    JITScriptStatus status = script->getJITStatus(fp->isConstructing());
 91    if (status == JITScript_Invalid)
 92        return Compile_Abort;
 93    if (status == JITScript_None && !cx->hasRunOption(JSOPTION_METHODJIT_ALWAYS)) {
 94        if ((cx->typeInferenceEnabled())
 95             ? script->incUseCount() <= INFER_USES_BEFORE_COMPILE
 96             : script->incUseCount() <= USES_BEFORE_COMPILE) {
 97            return Compile_Skipped;
 98        }
 99    }
100    if (status == JITScript_None)
101        return TryCompile(cx, fp->script(), fp->isConstructing());
102    return Compile_Okay;
103}
104
105}
106}
107
108#endif