michael@0: /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
michael@0:  * vim: set ts=8 sts=4 et sw=4 tw=99:
michael@0:  * This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #ifndef jit_BaselineDebugModeOSR_h
michael@0: #define jit_BaselineDebugModeOSR_h
michael@0: 
michael@0: #ifdef JS_ION
michael@0: 
michael@0: #include "jit/BaselineFrame.h"
michael@0: #include "jit/BaselineIC.h"
michael@0: #include "jit/BaselineJIT.h"
michael@0: 
michael@0: namespace js {
michael@0: namespace jit {
michael@0: 
michael@0: // Note that this file and the corresponding .cpp implement debug mode
michael@0: // on-stack recompilation. This is to be distinguished from ordinary
michael@0: // Baseline->Ion OSR, which is used to jump into compiled loops.
michael@0: 
michael@0: //
michael@0: // A volatile location due to recompilation of an on-stack baseline script
michael@0: // (e.g., for debug mode toggling).
michael@0: //
michael@0: // It is usually used in fallback stubs which may trigger on-stack
michael@0: // recompilation by calling out into the VM. Example use:
michael@0: //
michael@0: //     DebugModeOSRVolatileStub<FallbackStubT *> stub(frame, stub_)
michael@0: //
michael@0: //     // Call out to the VM
michael@0: //     // Other effectful operations like TypeScript::Monitor
michael@0: //
michael@0: //     if (stub.invalid())
michael@0: //         return true;
michael@0: //
michael@0: //     // First use of stub after VM call.
michael@0: //
michael@0: template <typename T>
michael@0: class DebugModeOSRVolatileStub
michael@0: {
michael@0:     T stub_;
michael@0:     BaselineFrame *frame_;
michael@0:     uint32_t pcOffset_;
michael@0: 
michael@0:   public:
michael@0:     DebugModeOSRVolatileStub(BaselineFrame *frame, ICFallbackStub *stub)
michael@0:       : stub_(static_cast<T>(stub)),
michael@0:         frame_(frame),
michael@0:         pcOffset_(stub->icEntry()->pcOffset())
michael@0:     { }
michael@0: 
michael@0:     bool invalid() const {
michael@0:         ICEntry &entry = frame_->script()->baselineScript()->icEntryFromPCOffset(pcOffset_);
michael@0:         return stub_ != entry.fallbackStub();
michael@0:     }
michael@0: 
michael@0:     operator const T&() const { MOZ_ASSERT(!invalid()); return stub_; }
michael@0:     T operator->() const { MOZ_ASSERT(!invalid()); return stub_; }
michael@0:     T *address() { MOZ_ASSERT(!invalid()); return &stub_; }
michael@0:     const T *address() const { MOZ_ASSERT(!invalid()); return &stub_; }
michael@0:     T &get() { MOZ_ASSERT(!invalid()); return stub_; }
michael@0:     const T &get() const { MOZ_ASSERT(!invalid()); return stub_; }
michael@0: 
michael@0:     bool operator!=(const T &other) const { MOZ_ASSERT(!invalid()); return stub_ != other; }
michael@0:     bool operator==(const T &other) const { MOZ_ASSERT(!invalid()); return stub_ == other; }
michael@0: };
michael@0: 
michael@0: //
michael@0: // Auxiliary info to help the DebugModeOSRHandler fix up state.
michael@0: //
michael@0: struct BaselineDebugModeOSRInfo
michael@0: {
michael@0:     uint8_t *resumeAddr;
michael@0:     jsbytecode *pc;
michael@0:     PCMappingSlotInfo slotInfo;
michael@0:     ICEntry::Kind frameKind;
michael@0: 
michael@0:     // Filled in by SyncBaselineDebugModeOSRInfo.
michael@0:     uintptr_t stackAdjust;
michael@0:     Value valueR0;
michael@0:     Value valueR1;
michael@0: 
michael@0:     BaselineDebugModeOSRInfo(jsbytecode *pc, ICEntry::Kind kind)
michael@0:       : resumeAddr(nullptr),
michael@0:         pc(pc),
michael@0:         slotInfo(0),
michael@0:         frameKind(kind),
michael@0:         stackAdjust(0),
michael@0:         valueR0(UndefinedValue()),
michael@0:         valueR1(UndefinedValue())
michael@0:     { }
michael@0: 
michael@0:     void popValueInto(PCMappingSlotInfo::SlotLocation loc, Value *vp);
michael@0: };
michael@0: 
michael@0: bool
michael@0: RecompileOnStackBaselineScriptsForDebugMode(JSContext *cx, JSCompartment *comp);
michael@0: 
michael@0: } // namespace jit
michael@0: } // namespace js
michael@0: 
michael@0: #endif // JS_ION
michael@0: 
michael@0: #endif // jit_BaselineDebugModeOSR_h