diff -r 000000000000 -r 6474c204b198 js/src/jit/JitOptions.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit/JitOptions.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,161 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ * vim: set ts=8 sts=4 et sw=4 tw=99:
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "jit/JitOptions.h"
+
+#include "jsscript.h"
+
+using namespace js;
+using namespace js::jit;
+
+namespace js {
+namespace jit {
+
+JitOptions js_JitOptions;
+
+JitOptions::JitOptions()
+{
+    // Whether to perform expensive graph-consistency DEBUG-only assertions.
+    // It can be useful to disable this to reduce DEBUG-compile time of large
+    // asm.js programs.
+    checkGraphConsistency = true;
+
+#ifdef CHECK_OSIPOINT_REGISTERS
+    // Emit extra code to verify live regs at the start of a VM call
+    // are not modified before its OsiPoint.
+    checkOsiPointRegisters = false;
+#endif
+
+    // Whether to enable extra code to perform dynamic validation of
+    // RangeAnalysis results.
+    checkRangeAnalysis = false;
+
+    // Whether Ion should compile try-catch statements.
+    compileTryCatch = true;
+
+    // Toggle whether global value numbering is globally disabled.
+    disableGvn = false;
+
+    // Toggles whether loop invariant code motion is globally disabled.
+    disableLicm = false;
+
+    // Toggles whether inlining is globally disabled.
+    disableInlining = false;
+
+    // Toggles whether Edge Case Analysis is gobally disabled.
+    disableEdgeCaseAnalysis = false;
+
+    // Toggles whether Range Analysis is globally disabled.
+    disableRangeAnalysis = false;
+
+    // Toggles whether Unreachable Code Elimination is globally disabled.
+    disableUce = false;
+
+    // Toggles whether Effective Address Analysis is globally disabled.
+    disableEaa = false;
+
+    // Whether functions are compiled immediately.
+    eagerCompilation = false;
+
+    // Force how many invocation or loop iterations are needed before compiling
+    // a function with the highest ionmonkey optimization level.
+    // (i.e. OptimizationLevel_Normal)
+    forceDefaultIonUsesBeforeCompile = false;
+    forcedDefaultIonUsesBeforeCompile = 1000;
+
+    // Force the GVN kind to be optimistic or pessimistic instead of letting
+    // the optimization pass decide.
+    forceGvnKind = false;
+    forcedGvnKind = GVN_Optimistic;
+
+    // Force the used register allocator instead of letting the
+    // optimization pass decide.
+    forceRegisterAllocator = false;
+    forcedRegisterAllocator = RegisterAllocator_LSRA;
+
+    // Toggles whether large scripts are rejected.
+    limitScriptSize = true;
+
+    // Toggles whether functions may be entered at loop headers.
+    osr = true;
+
+    // How many invocations or loop iterations are needed before functions
+    // are compiled with the baseline compiler.
+    baselineUsesBeforeCompile = 10;
+
+    // Number of exception bailouts (resuming into catch/finally block) before
+    // we invalidate and forbid Ion compilation.
+    exceptionBailoutThreshold = 10;
+
+    // Number of bailouts without invalidation before we set
+    // JSScript::hadFrequentBailouts and invalidate.
+    frequentBailoutThreshold = 10;
+
+    // How many actual arguments are accepted on the C stack.
+    maxStackArgs = 4096;
+
+    // How many times we will try to enter a script via OSR before
+    // invalidating the script.
+    osrPcMismatchesBeforeRecompile = 6000;
+
+    // The bytecode length limit for small function.
+    //
+    // The default for this was arrived at empirically via benchmarking.
+    // We may want to tune it further after other optimizations have gone
+    // in.
+    smallFunctionMaxBytecodeLength_ = 100;
+
+    // How many uses of a parallel kernel before we attempt compilation.
+    usesBeforeCompilePar = 1;
+
+    // Whether to profile inlined functions in Ion or not.
+    profileInlineFrames = false;
+}
+
+bool
+JitOptions::isSmallFunction(JSScript *script) const
+{
+    return script->length() <= smallFunctionMaxBytecodeLength_;
+}
+
+void
+JitOptions::setEagerCompilation()
+{
+    eagerCompilation = true;
+    baselineUsesBeforeCompile = 0;
+    forceDefaultIonUsesBeforeCompile = true;
+    forcedDefaultIonUsesBeforeCompile = 0;
+}
+
+void
+JitOptions::setUsesBeforeCompile(uint32_t useCount)
+{
+    forceDefaultIonUsesBeforeCompile = true;
+    forcedDefaultIonUsesBeforeCompile = useCount;
+
+    // Undo eager compilation
+    if (eagerCompilation && useCount != 0) {
+        jit::JitOptions defaultValues;
+        eagerCompilation = false;
+        baselineUsesBeforeCompile = defaultValues.baselineUsesBeforeCompile;
+    }
+}
+
+void
+JitOptions::resetUsesBeforeCompile()
+{
+    forceDefaultIonUsesBeforeCompile = false;
+
+    // Undo eager compilation
+    if (eagerCompilation) {
+        jit::JitOptions defaultValues;
+        eagerCompilation = false;
+        baselineUsesBeforeCompile = defaultValues.baselineUsesBeforeCompile;
+    }
+}
+
+} // namespace jit
+} // namespace js