The Tor Browser: js/src/jit/BaselineDebugModeOSR.h@6474c204b198

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

     1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-

     2  * vim: set ts=8 sts=4 et sw=4 tw=99:

     3  * This Source Code Form is subject to the terms of the Mozilla Public

     4  * License, v. 2.0. If a copy of the MPL was not distributed with this

     5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

     7 #ifndef jit_BaselineDebugModeOSR_h

     8 #define jit_BaselineDebugModeOSR_h

    10 #ifdef JS_ION

    12 #include "jit/BaselineFrame.h"

    13 #include "jit/BaselineIC.h"

    14 #include "jit/BaselineJIT.h"

    16 namespace js {

    17 namespace jit {

    19 // Note that this file and the corresponding .cpp implement debug mode

    20 // on-stack recompilation. This is to be distinguished from ordinary

    21 // Baseline->Ion OSR, which is used to jump into compiled loops.

    23 //

    24 // A volatile location due to recompilation of an on-stack baseline script

    25 // (e.g., for debug mode toggling).

    26 //

    27 // It is usually used in fallback stubs which may trigger on-stack

    28 // recompilation by calling out into the VM. Example use:

    29 //

    30 //     DebugModeOSRVolatileStub<FallbackStubT *> stub(frame, stub_)

    31 //

    32 //     // Call out to the VM

    33 //     // Other effectful operations like TypeScript::Monitor

    34 //

    35 //     if (stub.invalid())

    36 //         return true;

    37 //

    38 //     // First use of stub after VM call.

    39 //

    40 template <typename T>

    41 class DebugModeOSRVolatileStub

    42 {

    43     T stub_;

    44     BaselineFrame *frame_;

    45     uint32_t pcOffset_;

    47   public:

    48     DebugModeOSRVolatileStub(BaselineFrame *frame, ICFallbackStub *stub)

    49       : stub_(static_cast<T>(stub)),

    50         frame_(frame),

    51         pcOffset_(stub->icEntry()->pcOffset())

    52     { }

    54     bool invalid() const {

    55         ICEntry &entry = frame_->script()->baselineScript()->icEntryFromPCOffset(pcOffset_);

    56         return stub_ != entry.fallbackStub();

    57     }

    59     operator const T&() const { MOZ_ASSERT(!invalid()); return stub_; }

    60     T operator->() const { MOZ_ASSERT(!invalid()); return stub_; }

    61     T *address() { MOZ_ASSERT(!invalid()); return &stub_; }

    62     const T *address() const { MOZ_ASSERT(!invalid()); return &stub_; }

    63     T &get() { MOZ_ASSERT(!invalid()); return stub_; }

    64     const T &get() const { MOZ_ASSERT(!invalid()); return stub_; }

    66     bool operator!=(const T &other) const { MOZ_ASSERT(!invalid()); return stub_ != other; }

    67     bool operator==(const T &other) const { MOZ_ASSERT(!invalid()); return stub_ == other; }

    68 };

    70 //

    71 // Auxiliary info to help the DebugModeOSRHandler fix up state.

    72 //

    73 struct BaselineDebugModeOSRInfo

    74 {

    75     uint8_t *resumeAddr;

    76     jsbytecode *pc;

    77     PCMappingSlotInfo slotInfo;

    78     ICEntry::Kind frameKind;

    80     // Filled in by SyncBaselineDebugModeOSRInfo.

    81     uintptr_t stackAdjust;

    82     Value valueR0;

    83     Value valueR1;

    85     BaselineDebugModeOSRInfo(jsbytecode *pc, ICEntry::Kind kind)

    86       : resumeAddr(nullptr),

    87         pc(pc),

    88         slotInfo(0),

    89         frameKind(kind),

    90         stackAdjust(0),

    91         valueR0(UndefinedValue()),

    92         valueR1(UndefinedValue())

    93     { }

    95     void popValueInto(PCMappingSlotInfo::SlotLocation loc, Value *vp);

    96 };

    98 bool

    99 RecompileOnStackBaselineScriptsForDebugMode(JSContext *cx, JSCompartment *comp);

   101 } // namespace jit

   102 } // namespace js

   104 #endif // JS_ION

   106 #endif // jit_BaselineDebugModeOSR_h

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