nmethod.hpp

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
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#ifndef SHARE_CODE_NMETHOD_HPP
#defineSHARE_CODE_NMETHOD_HPP

#include"code/codeBlob.hpp"
#include"code/pcDesc.hpp"
#include"oops/metadata.hpp"
#include"oops/method.hpp"

classAbstractCompiler;
classCompiledDirectCall;
classCompiledIC;
classCompiledICData;
classCompileTask;
classDepChange;
classDependencies;
classDirectiveSet;
classDebugInformationRecorder;
classExceptionHandlerTable;
classImplicitExceptionTable;
classJvmtiThreadState;
classMetadataClosure;
classNativeCallWrapper;
classOopIterateClosure;
classScopeDesc;
classxmlStream;

// This class is used internally by nmethods, to cache
// exception/pc/handler information.

classExceptionCache : publicCHeapObj<mtCode> {
friendclassVMStructs;
private:
enum { cache_size = 16 };
 Klass* _exception_type;
 address _pc[cache_size];
 address _handler[cache_size];
volatileint _count;
 ExceptionCache* volatile _next;
 ExceptionCache* _purge_list_next;

inline address pc_at(int index);
voidset_pc_at(int index, address a) { assert(index >= 0 && index < cache_size,""); _pc[index] = a; }

inline address handler_at(int index);
voidset_handler_at(int index, address a) { assert(index >= 0 && index < cache_size,""); _handler[index] = a; }

inlineintcount();
// increment_count is only called under lock, but there may be concurrent readers.
voidincrement_count();

public:

ExceptionCache(Handleexception, address pc, address handler);

 Klass* exception_type() { return _exception_type; }
 ExceptionCache* next();
voidset_next(ExceptionCache *ec);
 ExceptionCache* purge_list_next() { return _purge_list_next; }
voidset_purge_list_next(ExceptionCache *ec) { _purge_list_next = ec; }

 address match(Handleexception, address pc);
boolmatch_exception_with_space(Handleexception) ;
 address test_address(address addr);
booladd_address_and_handler(address addr, address handler) ;
};

// cache pc descs found in earlier inquiries
classPcDescCache {
friendclassVMStructs;
private:
enum { cache_size = 4 };
// The array elements MUST be volatile! Several threads may modify
// and read from the cache concurrently. find_pc_desc_internal has
// returned wrong results. C++ compiler (namely xlC12) may duplicate
// C++ field accesses if the elements are not volatile.
typedef PcDesc* PcDescPtr;
volatile PcDescPtr _pc_descs[cache_size]; // last cache_size pc_descs found
public:
PcDescCache() { DEBUG_ONLY(_pc_descs[0] = nullptr); }
voidinit_to(PcDesc* initial_pc_desc);
 PcDesc* find_pc_desc(int pc_offset, bool approximate);
voidadd_pc_desc(PcDesc* pc_desc);
 PcDesc* last_pc_desc() { return _pc_descs[0]; }
};

classPcDescContainer : publicCHeapObj<mtCode> {
private:
 PcDescCache _pc_desc_cache;
public:
PcDescContainer(PcDesc* initial_pc_desc) { _pc_desc_cache.init_to(initial_pc_desc); }

 PcDesc* find_pc_desc_internal(address pc, bool approximate, address code_begin,
 PcDesc* lower, PcDesc* upper);

 PcDesc* find_pc_desc(address pc, bool approximate, address code_begin, PcDesc* lower, PcDesc* upper)
#ifdef PRODUCT
 {
 PcDesc* desc = _pc_desc_cache.last_pc_desc();
assert(desc != nullptr, "PcDesc cache should be initialized already");
if (desc->pc_offset() == (pc - code_begin)) {
// Cached value matched
return desc;
 }
returnfind_pc_desc_internal(pc, approximate, code_begin, lower, upper);
 }
#endif
 ;
};

// nmethods (native methods) are the compiled code versions of Java methods.
//
// An nmethod contains:
// - Header (the nmethod structure)
// - Constant part (doubles, longs and floats used in nmethod)
// - Code part:
// - Code body
// - Exception handler
// - Stub code
// - OOP table
//
// As a CodeBlob, an nmethod references [mutable data] allocated on the C heap:
// - CodeBlob relocation data
// - Metainfo
// - JVMCI data
//
// An nmethod references [immutable data] allocated on C heap:
// - Dependency assertions data
// - Implicit null table array
// - Handler entry point array
// - Debugging information:
// - Scopes data array
// - Scopes pcs array
// - JVMCI speculations array

#if INCLUDE_JVMCI
classFailedSpeculation;
classJVMCINMethodData;
#endif

classnmethod : publicCodeBlob {
friendclassVMStructs;
friendclassJVMCIVMStructs;
friendclassCodeCache; // scavengable oops
friendclassJVMCINMethodData;
friendclassDeoptimizationScope;

private:

// Used to track in which deoptimize handshake this method will be deoptimized.
uint64_t _deoptimization_generation;

uint64_t _gc_epoch;

 Method* _method;

// To reduce header size union fields which usages do not overlap.
union {
// To support simple linked-list chaining of nmethods:
 nmethod* _osr_link; // from InstanceKlass::osr_nmethods_head
struct {
// These are used for compiled synchronized native methods to
// locate the owner and stack slot for the BasicLock. They are
// needed because there is no debug information for compiled native
// wrappers and the oop maps are insufficient to allow
// frame::retrieve_receiver() to work. Currently they are expected
// to be byte offsets from the Java stack pointer for maximum code
// sharing between platforms. JVMTI's GetLocalInstance() uses these
// offsets to find the receiver for non-static native wrapper frames.
 ByteSize _native_receiver_sp_offset;
 ByteSize _native_basic_lock_sp_offset;
 };
 };

// nmethod's read-only data
 address _immutable_data;

 PcDescContainer* _pc_desc_container;
 ExceptionCache* volatile _exception_cache;

void* _gc_data;

structoops_do_mark_link; // Opaque data type.
static nmethod* volatile _oops_do_mark_nmethods;
 oops_do_mark_link* volatile _oops_do_mark_link;

 CompiledICData* _compiled_ic_data;

// offsets for entry points
 address _osr_entry_point; // entry point for on stack replacement
uint16_t _entry_offset; // entry point with class check
uint16_t _verified_entry_offset; // entry point without class check
int _entry_bci; // != InvocationEntryBci if this nmethod is an on-stack replacement method
int _immutable_data_size;

// _consts_offset == _content_offset because SECT_CONSTS is first in code buffer

int _skipped_instructions_size;

int _stub_offset;

// Offsets for different stubs section parts
int _exception_offset;
// All deoptee's will resume execution at this location described by
// this offset.
int _deopt_handler_offset;
// All deoptee's at a MethodHandle call site will resume execution
// at this location described by this offset.
int _deopt_mh_handler_offset;
// Offset (from insts_end) of the unwind handler if it exists
int16_t _unwind_handler_offset;
// Number of arguments passed on the stack
uint16_t _num_stack_arg_slots;

uint16_t _oops_size;
#if INCLUDE_JVMCI
uint16_t _jvmci_data_size;
#endif

// Offset in immutable data section
// _dependencies_offset == 0
uint16_t _nul_chk_table_offset;
uint16_t _handler_table_offset; // This table could be big in C1 code
int _scopes_pcs_offset;
int _scopes_data_offset;
#if INCLUDE_JVMCI
int _speculations_offset;
#endif

// location in frame (offset for sp) that deopt can store the original
// pc during a deopt.
int _orig_pc_offset;

int _compile_id; // which compilation made this nmethod
 CompLevel _comp_level; // compilation level (s1)
 CompilerType _compiler_type; // which compiler made this nmethod (u1)

// Local state used to keep track of whether unloading is happening or not
volatileuint8_t _is_unloading_state;

// Protected by NMethodState_lock
volatilesignedchar _state; // {not_installed, in_use, not_entrant}

// set during construction
uint8_t _has_unsafe_access:1, // May fault due to unsafe access.
 _has_method_handle_invokes:1,// Has this method MethodHandle invokes?
 _has_wide_vectors:1, // Preserve wide vectors at safepoints
 _has_monitors:1, // Fastpath monitor detection for continuations
 _has_scoped_access:1, // used by for shared scope closure (scopedMemoryAccess.cpp)
 _has_flushed_dependencies:1, // Used for maintenance of dependencies (under CodeCache_lock)
 _is_unlinked:1, // mark during class unloading
 _load_reported:1; // used by jvmti to track if an event has been posted for this nmethod

enum DeoptimizationStatus : u1 {
 not_marked,
 deoptimize,
 deoptimize_noupdate,
 deoptimize_done
 };

volatile DeoptimizationStatus _deoptimization_status; // Used for stack deoptimization

 DeoptimizationStatus deoptimization_status() const {
returnAtomic::load(&_deoptimization_status);
 }

// Initialize fields to their default values
voidinit_defaults(CodeBuffer *code_buffer, CodeOffsets* offsets);

// Post initialization
voidpost_init();

// For native wrappers
nmethod(Method* method,
 CompilerType type,
int nmethod_size,
int compile_id,
 CodeOffsets* offsets,
 CodeBuffer *code_buffer,
int frame_size,
 ByteSize basic_lock_owner_sp_offset, /* synchronized natives only */
 ByteSize basic_lock_sp_offset, /* synchronized natives only */
 OopMapSet* oop_maps,
int mutable_data_size);

// For normal JIT compiled code
nmethod(Method* method,
 CompilerType type,
int nmethod_size,
int immutable_data_size,
int mutable_data_size,
int compile_id,
int entry_bci,
 address immutable_data,
 CodeOffsets* offsets,
int orig_pc_offset,
 DebugInformationRecorder *recorder,
 Dependencies* dependencies,
 CodeBuffer *code_buffer,
int frame_size,
 OopMapSet* oop_maps,
 ExceptionHandlerTable* handler_table,
 ImplicitExceptionTable* nul_chk_table,
 AbstractCompiler* compiler,
 CompLevel comp_level
#if INCLUDE_JVMCI
 , char* speculations = nullptr,
int speculations_len = 0,
 JVMCINMethodData* jvmci_data = nullptr
#endif
 );

// helper methods
void* operatornew(size_t size, int nmethod_size, int comp_level) throw();

// For method handle intrinsics: Try MethodNonProfiled, MethodProfiled and NonNMethod.
// Attention: Only allow NonNMethod space for special nmethods which don't need to be
// findable by nmethod iterators! In particular, they must not contain oops!
void* operatornew(size_t size, int nmethod_size, bool allow_NonNMethod_space) throw();

constchar* reloc_string_for(u_char* begin, u_char* end);

booltry_transition(signedchar new_state);

// Returns true if this thread changed the state of the nmethod or
// false if another thread performed the transition.
boolmake_entrant() { Unimplemented(); returnfalse; }
voidinc_decompile_count();

// Inform external interfaces that a compiled method has been unloaded
voidpost_compiled_method_unload();

 PcDesc* find_pc_desc(address pc, bool approximate) {
if (_pc_desc_container == nullptr) returnnullptr; // native method
return _pc_desc_container->find_pc_desc(pc, approximate, code_begin(), scopes_pcs_begin(), scopes_pcs_end());
 }

// STW two-phase nmethod root processing helpers.
//
// When determining liveness of a given nmethod to do code cache unloading,
// some collectors need to do different things depending on whether the nmethods
// need to absolutely be kept alive during root processing; "strong"ly reachable
// nmethods are known to be kept alive at root processing, but the liveness of
// "weak"ly reachable ones is to be determined later.
//
// We want to allow strong and weak processing of nmethods by different threads
// at the same time without heavy synchronization. Additional constraints are
// to make sure that every nmethod is processed a minimal amount of time, and
// nmethods themselves are always iterated at most once at a particular time.
//
// Note that strong processing work must be a superset of weak processing work
// for this code to work.
//
// We store state and claim information in the _oops_do_mark_link member, using
// the two LSBs for the state and the remaining upper bits for linking together
// nmethods that were already visited.
// The last element is self-looped, i.e. points to itself to avoid some special
// "end-of-list" sentinel value.
//
// _oops_do_mark_link special values:
//
// _oops_do_mark_link == nullptr: the nmethod has not been visited at all yet, i.e.
// is Unclaimed.
//
// For other values, its lowest two bits indicate the following states of the nmethod:
//
// weak_request (WR): the nmethod has been claimed by a thread for weak processing
// weak_done (WD): weak processing has been completed for this nmethod.
// strong_request (SR): the nmethod has been found to need strong processing while
// being weak processed.
// strong_done (SD): strong processing has been completed for this nmethod .
//
// The following shows the _only_ possible progressions of the _oops_do_mark_link
// pointer.
//
// Given
// N as the nmethod
// X the current next value of _oops_do_mark_link
//
// Unclaimed (C)-> N|WR (C)-> X|WD: the nmethod has been processed weakly by
// a single thread.
// Unclaimed (C)-> N|WR (C)-> X|WD (O)-> X|SD: after weak processing has been
// completed (as above) another thread found that the nmethod needs strong
// processing after all.
// Unclaimed (C)-> N|WR (O)-> N|SR (C)-> X|SD: during weak processing another
// thread finds that the nmethod needs strong processing, marks it as such and
// terminates. The original thread completes strong processing.
// Unclaimed (C)-> N|SD (C)-> X|SD: the nmethod has been processed strongly from
// the beginning by a single thread.
//
// "|" describes the concatenation of bits in _oops_do_mark_link.
//
// The diagram also describes the threads responsible for changing the nmethod to
// the next state by marking the _transition_ with (C) and (O), which mean "current"
// and "other" thread respectively.
//

// States used for claiming nmethods during root processing.
staticconstuint claim_weak_request_tag = 0;
staticconstuint claim_weak_done_tag = 1;
staticconstuint claim_strong_request_tag = 2;
staticconstuint claim_strong_done_tag = 3;

static oops_do_mark_link* mark_link(nmethod* nm, uint tag) {
assert(tag <= claim_strong_done_tag, "invalid tag %u", tag);
assert(is_aligned(nm, 4), "nmethod pointer must have zero lower two LSB");
return (oops_do_mark_link*)(((uintptr_t)nm & ~0x3) | tag);
 }

staticuintextract_state(oops_do_mark_link* link) {
return (uint)((uintptr_t)link & 0x3);
 }

static nmethod* extract_nmethod(oops_do_mark_link* link) {
return (nmethod*)((uintptr_t)link & ~0x3);
 }

voidoops_do_log_change(constchar* state);

staticbooloops_do_has_weak_request(oops_do_mark_link* next) {
returnextract_state(next) == claim_weak_request_tag;
 }

staticbooloops_do_has_any_strong_state(oops_do_mark_link* next) {
returnextract_state(next) >= claim_strong_request_tag;
 }

// Attempt Unclaimed -> N|WR transition. Returns true if successful.
booloops_do_try_claim_weak_request();

// Attempt Unclaimed -> N|SD transition. Returns the current link.
 oops_do_mark_link* oops_do_try_claim_strong_done();
// Attempt N|WR -> X|WD transition. Returns nullptr if successful, X otherwise.
 nmethod* oops_do_try_add_to_list_as_weak_done();

// Attempt X|WD -> N|SR transition. Returns the current link.
 oops_do_mark_link* oops_do_try_add_strong_request(oops_do_mark_link* next);
// Attempt X|WD -> X|SD transition. Returns true if successful.
booloops_do_try_claim_weak_done_as_strong_done(oops_do_mark_link* next);

// Do the N|SD -> X|SD transition.
voidoops_do_add_to_list_as_strong_done();

// Sets this nmethod as strongly claimed (as part of N|SD -> X|SD and N|SR -> X|SD
// transitions).
voidoops_do_set_strong_done(nmethod* old_head);

public:
// create nmethod with entry_bci
static nmethod* new_nmethod(const methodHandle& method,
int compile_id,
int entry_bci,
 CodeOffsets* offsets,
int orig_pc_offset,
 DebugInformationRecorder* recorder,
 Dependencies* dependencies,
 CodeBuffer *code_buffer,
int frame_size,
 OopMapSet* oop_maps,
 ExceptionHandlerTable* handler_table,
 ImplicitExceptionTable* nul_chk_table,
 AbstractCompiler* compiler,
 CompLevel comp_level
#if INCLUDE_JVMCI
 , char* speculations = nullptr,
int speculations_len = 0,
 JVMCINMethodData* jvmci_data = nullptr
#endif
 );

static nmethod* new_native_nmethod(const methodHandle& method,
int compile_id,
 CodeBuffer *code_buffer,
int vep_offset,
int frame_complete,
int frame_size,
 ByteSize receiver_sp_offset,
 ByteSize basic_lock_sp_offset,
 OopMapSet* oop_maps,
int exception_handler = -1);

 Method* method () const { return _method; }
boolis_native_method() const { return _method != nullptr && _method->is_native(); }
boolis_java_method () const { return _method != nullptr && !_method->is_native(); }
boolis_osr_method () const { return _entry_bci != InvocationEntryBci; }

// Compiler task identification. Note that all OSR methods
// are numbered in an independent sequence if CICountOSR is true,
// and native method wrappers are also numbered independently if
// CICountNative is true.
intcompile_id() const { return _compile_id; }
constchar* compile_kind() const;

inlineboolis_compiled_by_c1 () const { return _compiler_type == compiler_c1; }
inlineboolis_compiled_by_c2 () const { return _compiler_type == compiler_c2; }
inlineboolis_compiled_by_jvmci() const { return _compiler_type == compiler_jvmci; }
 CompilerType compiler_type () const { return _compiler_type; }
constchar* compiler_name () const;

// boundaries for different parts
 address consts_begin () const { returncontent_begin(); }
 address consts_end () const { returncode_begin() ; }
 address insts_begin () const { returncode_begin() ; }
 address insts_end () const { returnheader_begin() + _stub_offset ; }
 address stub_begin () const { returnheader_begin() + _stub_offset ; }
 address stub_end () const { returncode_end() ; }
 address exception_begin () const { returnheader_begin() + _exception_offset ; }
 address deopt_handler_begin () const { returnheader_begin() + _deopt_handler_offset ; }
 address deopt_mh_handler_begin() const { returnheader_begin() + _deopt_mh_handler_offset ; }
 address unwind_handler_begin () const { return _unwind_handler_offset != -1 ? (insts_end() - _unwind_handler_offset) : nullptr; }
 oop* oops_begin () const { return (oop*) data_begin(); }
 oop* oops_end () const { return (oop*) data_end(); }

// mutable data
 Metadata** metadata_begin () const { return (Metadata**) (mutable_data_begin() + _relocation_size); }
#if INCLUDE_JVMCI
 Metadata** metadata_end () const { return (Metadata**) (mutable_data_end() - _jvmci_data_size); }
 address jvmci_data_begin () const { returnmutable_data_end() - _jvmci_data_size; }
 address jvmci_data_end () const { returnmutable_data_end(); }
#else
 Metadata** metadata_end () const { return (Metadata**) mutable_data_end(); }
#endif

// immutable data
 address immutable_data_begin () const { return _immutable_data; }
 address immutable_data_end () const { return _immutable_data + _immutable_data_size ; }
 address dependencies_begin () const { return _immutable_data; }
 address dependencies_end () const { return _immutable_data + _nul_chk_table_offset; }
 address nul_chk_table_begin () const { return _immutable_data + _nul_chk_table_offset; }
 address nul_chk_table_end () const { return _immutable_data + _handler_table_offset; }
 address handler_table_begin () const { return _immutable_data + _handler_table_offset; }
 address handler_table_end () const { return _immutable_data + _scopes_pcs_offset ; }
 PcDesc* scopes_pcs_begin () const { return (PcDesc*)(_immutable_data + _scopes_pcs_offset) ; }
 PcDesc* scopes_pcs_end () const { return (PcDesc*)(_immutable_data + _scopes_data_offset) ; }
 address scopes_data_begin () const { return _immutable_data + _scopes_data_offset ; }

#if INCLUDE_JVMCI
 address scopes_data_end () const { return _immutable_data + _speculations_offset ; }
 address speculations_begin () const { return _immutable_data + _speculations_offset ; }
 address speculations_end () const { returnimmutable_data_end(); }
#else
 address scopes_data_end () const { returnimmutable_data_end(); }
#endif

// Sizes
intimmutable_data_size() const { return _immutable_data_size; }
intconsts_size () const { returnint( consts_end () - consts_begin ()); }
intinsts_size () const { returnint( insts_end () - insts_begin ()); }
intstub_size () const { returnint( stub_end () - stub_begin ()); }
intoops_size () const { returnint((address) oops_end () - (address) oops_begin ()); }
intmetadata_size () const { returnint((address) metadata_end () - (address) metadata_begin ()); }
intscopes_data_size () const { returnint( scopes_data_end () - scopes_data_begin ()); }
intscopes_pcs_size () const { returnint((intptr_t)scopes_pcs_end () - (intptr_t)scopes_pcs_begin ()); }
intdependencies_size () const { returnint( dependencies_end () - dependencies_begin ()); }
inthandler_table_size () const { returnint( handler_table_end() - handler_table_begin()); }
intnul_chk_table_size () const { returnint( nul_chk_table_end() - nul_chk_table_begin()); }
#if INCLUDE_JVMCI
intspeculations_size () const { returnint( speculations_end () - speculations_begin ()); }
intjvmci_data_size () const { returnint( jvmci_data_end () - jvmci_data_begin ()); }
#endif

intoops_count() const { assert(oops_size() % oopSize == 0, ""); return (oops_size() / oopSize) + 1; }
intmetadata_count() const { assert(metadata_size() % wordSize == 0, ""); return (metadata_size() / wordSize) + 1; }

intskipped_instructions_size () const { return _skipped_instructions_size; }
inttotal_size() const;

// Containment
boolconsts_contains (address addr) const { returnconsts_begin () <= addr && addr < consts_end (); }
// Returns true if a given address is in the 'insts' section. The method
// insts_contains_inclusive() is end-inclusive.
boolinsts_contains (address addr) const { returninsts_begin () <= addr && addr < insts_end (); }
boolinsts_contains_inclusive(address addr) const { returninsts_begin () <= addr && addr <= insts_end (); }
boolstub_contains (address addr) const { returnstub_begin () <= addr && addr < stub_end (); }
booloops_contains (oop* addr) const { returnoops_begin () <= addr && addr < oops_end (); }
boolmetadata_contains (Metadata** addr) const { returnmetadata_begin () <= addr && addr < metadata_end (); }
boolscopes_data_contains (address addr) const { returnscopes_data_begin () <= addr && addr < scopes_data_end (); }
boolscopes_pcs_contains (PcDesc* addr) const { returnscopes_pcs_begin () <= addr && addr < scopes_pcs_end (); }
boolhandler_table_contains (address addr) const { returnhandler_table_begin() <= addr && addr < handler_table_end(); }
boolnul_chk_table_contains (address addr) const { returnnul_chk_table_begin() <= addr && addr < nul_chk_table_end(); }

// entry points
 address entry_point() const { returncode_begin() + _entry_offset; } // normal entry point
 address verified_entry_point() const { returncode_begin() + _verified_entry_offset; } // if klass is correct

enum : signedchar { not_installed = -1, // in construction, only the owner doing the construction is
// allowed to advance state
 in_use = 0, // executable nmethod
 not_entrant = 1// marked for deoptimization but activations may still exist
 };

// flag accessing and manipulation
boolis_not_installed() const { return _state == not_installed; }
boolis_in_use() const { return _state <= in_use; }
boolis_not_entrant() const { return _state == not_entrant; }
intget_state() const { return _state; }

voidclear_unloading_state();
// Heuristically deduce an nmethod isn't worth keeping around
boolis_cold();
boolis_unloading();
voiddo_unloading(bool unloading_occurred);

boolmake_in_use() {
returntry_transition(in_use);
 }
// Make the nmethod non entrant. The nmethod will continue to be
// alive. It is used when an uncommon trap happens. Returns true
// if this thread changed the state of the nmethod or false if
// another thread performed the transition.
boolmake_not_entrant(constchar* reason);
boolmake_not_used() { returnmake_not_entrant("not used"); }

boolis_marked_for_deoptimization() const { returndeoptimization_status() != not_marked; }
boolhas_been_deoptimized() const { returndeoptimization_status() == deoptimize_done; }
voidset_deoptimized_done();

boolupdate_recompile_counts() const {
// Update recompile counts when either the update is explicitly requested (deoptimize)
// or the nmethod is not marked for deoptimization at all (not_marked).
// The latter happens during uncommon traps when deoptimized nmethod is made not entrant.
 DeoptimizationStatus status = deoptimization_status();
return status != deoptimize_noupdate && status != deoptimize_done;
 }

// tells whether frames described by this nmethod can be deoptimized
// note: native wrappers cannot be deoptimized.
boolcan_be_deoptimized() const { returnis_java_method(); }

boolhas_dependencies() { returndependencies_size() != 0; }
voidprint_dependencies_on(outputStream* out) PRODUCT_RETURN;
voidflush_dependencies();

template<typename T>
 T* gc_data() const { returnreinterpret_cast<T*>(_gc_data); }
template<typename T>
voidset_gc_data(T* gc_data) { _gc_data = reinterpret_cast<void*>(gc_data); }

boolhas_unsafe_access() const { return _has_unsafe_access; }
voidset_has_unsafe_access(bool z) { _has_unsafe_access = z; }

boolhas_monitors() const { return _has_monitors; }
voidset_has_monitors(bool z) { _has_monitors = z; }

boolhas_scoped_access() const { return _has_scoped_access; }
voidset_has_scoped_access(bool z) { _has_scoped_access = z; }

boolhas_method_handle_invokes() const { return _has_method_handle_invokes; }
voidset_has_method_handle_invokes(bool z) { _has_method_handle_invokes = z; }

boolhas_wide_vectors() const { return _has_wide_vectors; }
voidset_has_wide_vectors(bool z) { _has_wide_vectors = z; }

boolhas_flushed_dependencies() const { return _has_flushed_dependencies; }
voidset_has_flushed_dependencies(bool z) {
assert(!has_flushed_dependencies(), "should only happen once");
 _has_flushed_dependencies = z;
 }

boolis_unlinked() const { return _is_unlinked; }
voidset_is_unlinked() {
assert(!_is_unlinked, "already unlinked");
 _is_unlinked = true;
 }

intcomp_level() const { return _comp_level; }

// Support for oops in scopes and relocs:
// Note: index 0 is reserved for null.
 oop oop_at(int index) const;
 oop oop_at_phantom(int index) const; // phantom reference
 oop* oop_addr_at(int index) const { // for GC
// relocation indexes are biased by 1 (because 0 is reserved)
assert(index > 0 && index <= oops_count(), "must be a valid non-zero index");
return &oops_begin()[index - 1];
 }

// Support for meta data in scopes and relocs:
// Note: index 0 is reserved for null.
 Metadata* metadata_at(int index) const { returnindex == 0 ? nullptr: *metadata_addr_at(index); }
 Metadata** metadata_addr_at(int index) const { // for GC
// relocation indexes are biased by 1 (because 0 is reserved)
assert(index > 0 && index <= metadata_count(), "must be a valid non-zero index");
return &metadata_begin()[index - 1];
 }

voidcopy_values(GrowableArray<jobject>* oops);
voidcopy_values(GrowableArray<Metadata*>* metadata);
voidcopy_values(GrowableArray<address>* metadata) {} // Nothing to do

// Relocation support
private:
voidfix_oop_relocations(address begin, address end, bool initialize_immediates);
inlinevoidinitialize_immediate_oop(oop* dest, jobject handle);

protected:
 address oops_reloc_begin() const;

public:
voidfix_oop_relocations(address begin, address end) { fix_oop_relocations(begin, end, false); }
voidfix_oop_relocations() { fix_oop_relocations(nullptr, nullptr, false); }

boolis_at_poll_return(address pc);
boolis_at_poll_or_poll_return(address pc);

protected:
// Exception cache support
// Note: _exception_cache may be read and cleaned concurrently.
 ExceptionCache* exception_cache() const { return _exception_cache; }
 ExceptionCache* exception_cache_acquire() const;

public:
 address handler_for_exception_and_pc(Handleexception, address pc);
voidadd_handler_for_exception_and_pc(Handleexception, address pc, address handler);
voidclean_exception_cache();

voidadd_exception_cache_entry(ExceptionCache* new_entry);
 ExceptionCache* exception_cache_entry_for_exception(Handleexception);


// MethodHandle
boolis_method_handle_return(address return_pc);
// Deopt
// Return true is the PC is one would expect if the frame is being deopted.
inlineboolis_deopt_pc(address pc);
inlineboolis_deopt_mh_entry(address pc);
inlineboolis_deopt_entry(address pc);

// Accessor/mutator for the original pc of a frame before a frame was deopted.
 address get_original_pc(const frame* fr) { return *orig_pc_addr(fr); }
voidset_original_pc(const frame* fr, address pc) { *orig_pc_addr(fr) = pc; }

constchar* state() const;

boolinlinecache_check_contains(address addr) const {
return (addr >= code_begin() && addr < verified_entry_point());
 }

voidpreserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f);

// implicit exceptions support
 address continuation_for_implicit_div0_exception(address pc) { returncontinuation_for_implicit_exception(pc, true); }
 address continuation_for_implicit_null_exception(address pc) { returncontinuation_for_implicit_exception(pc, false); }

// Inline cache support for class unloading and nmethod unloading
private:
voidcleanup_inline_caches_impl(bool unloading_occurred, bool clean_all);

 address continuation_for_implicit_exception(address pc, bool for_div0_check);

public:
// Serial version used by whitebox test
voidcleanup_inline_caches_whitebox();

voidclear_inline_caches();

// Execute nmethod barrier code, as if entering through nmethod call.
voidrun_nmethod_entry_barrier();

voidverify_oop_relocations();

boolhas_evol_metadata();

 Method* attached_method(address call_pc);
 Method* attached_method_before_pc(address pc);

// GC unloading support
// Cleans unloaded klasses and unloaded nmethods in inline caches

voidunload_nmethod_caches(bool class_unloading_occurred);

voidunlink_from_method();

// On-stack replacement support
intosr_entry_bci() const { assert(is_osr_method(), "wrong kind of nmethod"); return _entry_bci; }
 address osr_entry() const { assert(is_osr_method(), "wrong kind of nmethod"); return _osr_entry_point; }
 nmethod* osr_link() const { return _osr_link; }
voidset_osr_link(nmethod *n) { _osr_link = n; }
voidinvalidate_osr_method();

intnum_stack_arg_slots(bool rounded = true) const {
return rounded ? align_up(_num_stack_arg_slots, 2) : _num_stack_arg_slots;
 }

// Verify calls to dead methods have been cleaned.
voidverify_clean_inline_caches();

// Unlink this nmethod from the system
voidunlink();

// Deallocate this nmethod - called by the GC
voidpurge(bool unregister_nmethod);

// See comment at definition of _last_seen_on_stack
voidmark_as_maybe_on_stack();
boolis_maybe_on_stack();

// Evolution support. We make old (discarded) compiled methods point to new Method*s.
voidset_method(Method* method) { _method = method; }

#if INCLUDE_JVMCI
// Gets the JVMCI name of this nmethod.
constchar* jvmci_name();

// Records the pending failed speculation in the
// JVMCI speculation log associated with this nmethod.
voidupdate_speculation(JavaThread* thread);

// Gets the data specific to a JVMCI compiled method.
// This returns a non-nullptr value iff this nmethod was
// compiled by the JVMCI compiler.
 JVMCINMethodData* jvmci_nmethod_data() const {
returnjvmci_data_size() == 0 ? nullptr : (JVMCINMethodData*) jvmci_data_begin();
 }
#endif

voidoops_do(OopClosure* f) { oops_do(f, false); }
voidoops_do(OopClosure* f, bool allow_dead);

// All-in-one claiming of nmethods: returns true if the caller successfully claimed that
// nmethod.
booloops_do_try_claim();

// Loom support for following nmethods on the stack
voidfollow_nmethod(OopIterateClosure* cl);

// Class containing callbacks for the oops_do_process_weak/strong() methods
// below.
classOopsDoProcessor {
public:
// Process the oops of the given nmethod based on whether it has been called
// in a weak or strong processing context, i.e. apply either weak or strong
// work on it.
virtualvoiddo_regular_processing(nmethod* nm) = 0;
// Assuming that the oops of the given nmethod has already been its weak
// processing applied, apply the remaining strong processing part.
virtualvoiddo_remaining_strong_processing(nmethod* nm) = 0;
 };

// The following two methods do the work corresponding to weak/strong nmethod
// processing.
voidoops_do_process_weak(OopsDoProcessor* p);
voidoops_do_process_strong(OopsDoProcessor* p);

staticvoidoops_do_marking_prologue();
staticvoidoops_do_marking_epilogue();

private:
 ScopeDesc* scope_desc_in(address begin, address end);

 address* orig_pc_addr(const frame* fr);

// used by jvmti to track if the load events has been reported
boolload_reported() const { return _load_reported; }
voidset_load_reported() { _load_reported = true; }

public:
// ScopeDesc retrieval operation
 PcDesc* pc_desc_at(address pc) { returnfind_pc_desc(pc, false); }
// pc_desc_near returns the first PcDesc at or after the given pc.
 PcDesc* pc_desc_near(address pc) { returnfind_pc_desc(pc, true); }

// ScopeDesc for an instruction
 ScopeDesc* scope_desc_at(address pc);
 ScopeDesc* scope_desc_near(address pc);

// copying of debugging information
voidcopy_scopes_pcs(PcDesc* pcs, int count);
voidcopy_scopes_data(address buffer, int size);

intorig_pc_offset() { return _orig_pc_offset; }

// Post successful compilation
voidpost_compiled_method(CompileTask* task);

// jvmti support:
voidpost_compiled_method_load_event(JvmtiThreadState* state = nullptr);

// verify operations
voidverify();
voidverify_scopes();
voidverify_interrupt_point(address interrupt_point, bool is_inline_cache);

// Disassemble this nmethod with additional debug information, e.g. information about blocks.
voiddecode2(outputStream* st) const;
voidprint_constant_pool(outputStream* st);

// Avoid hiding of parent's 'decode(outputStream*)' method.
voiddecode(outputStream* st) const { decode2(st); } // just delegate here.

// printing support
voidprint_on_impl(outputStream* st) const;
voidprint_code();
voidprint_value_on_impl(outputStream* st) const;

#if defined(SUPPORT_DATA_STRUCTS)
// print output in opt build for disassembler library
voidprint_relocations() PRODUCT_RETURN;
voidprint_pcs_on(outputStream* st);
voidprint_scopes() { print_scopes_on(tty); }
voidprint_scopes_on(outputStream* st) PRODUCT_RETURN;
voidprint_handler_table();
voidprint_nul_chk_table();
voidprint_recorded_oop(int log_n, int index);
voidprint_recorded_oops();
voidprint_recorded_metadata();

voidprint_oops(outputStream* st); // oops from the underlying CodeBlob.
voidprint_metadata(outputStream* st); // metadata in metadata pool.
#else
voidprint_pcs_on(outputStream* st) { return; }
#endif

voidprint_calls(outputStream* st) PRODUCT_RETURN;
staticvoidprint_statistics() PRODUCT_RETURN;

voidmaybe_print_nmethod(const DirectiveSet* directive);
voidprint_nmethod(bool print_code);

voidprint_on_with_msg(outputStream* st, constchar* msg) const;

// Logging
voidlog_identity(xmlStream* log) const;
voidlog_new_nmethod() const;
voidlog_state_change(constchar* reason) const;

// Prints block-level comments, including nmethod specific block labels:
voidprint_nmethod_labels(outputStream* stream, address block_begin, bool print_section_labels=true) const;
constchar* nmethod_section_label(address pos) const;

// returns whether this nmethod has code comments.
boolhas_code_comment(address begin, address end);
// Prints a comment for one native instruction (reloc info, pc desc)
voidprint_code_comment_on(outputStream* st, int column, address begin, address end);

// tells if this compiled method is dependent on the given changes,
// and the changes have invalidated it
boolcheck_dependency_on(DepChange& changes);

// Fast breakpoint support. Tells if this compiled method is
// dependent on the given method. Returns true if this nmethod
// corresponds to the given method as well.
boolis_dependent_on_method(Method* dependee);

// JVMTI's GetLocalInstance() support
 ByteSize native_receiver_sp_offset() {
assert(is_native_method(), "sanity");
return _native_receiver_sp_offset;
 }
 ByteSize native_basic_lock_sp_offset() {
assert(is_native_method(), "sanity");
return _native_basic_lock_sp_offset;
 }

// support for code generation
static ByteSize osr_entry_point_offset() { returnbyte_offset_of(nmethod, _osr_entry_point); }
static ByteSize state_offset() { returnbyte_offset_of(nmethod, _state); }

voidmetadata_do(MetadataClosure* f);

 address call_instruction_address(address pc) const;

voidmake_deoptimized();
voidfinalize_relocations();

classVptr : publicCodeBlob::Vptr {
voidprint_on(const CodeBlob* instance, outputStream* st) constoverride {
 ttyLocker ttyl;
 instance->as_nmethod()->print_on_impl(st);
 }
voidprint_value_on(const CodeBlob* instance, outputStream* st) constoverride {
 instance->as_nmethod()->print_value_on_impl(st);
 }
 };

staticconst Vptr _vpntr;
};