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 /* -*- 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