codeBlob.hpp

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
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 *
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 * version 2 for more details (a copy is included in the LICENSE file that
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 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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*/

#ifndef SHARE_CODE_CODEBLOB_HPP
#defineSHARE_CODE_CODEBLOB_HPP

#include"asm/codeBuffer.hpp"
#include"compiler/compilerDefinitions.hpp"
#include"compiler/oopMap.hpp"
#include"runtime/javaFrameAnchor.hpp"
#include"runtime/frame.hpp"
#include"runtime/handles.hpp"
#include"utilities/align.hpp"
#include"utilities/macros.hpp"

classImmutableOopMap;
classImmutableOopMapSet;
classJNIHandleBlock;
classOopMapSet;

// CodeBlob Types
// Used in the CodeCache to assign CodeBlobs to different CodeHeaps
enumclassCodeBlobType {
 MethodNonProfiled = 0, // Execution level 1 and 4 (non-profiled) nmethods (including native nmethods)
 MethodProfiled = 1, // Execution level 2 and 3 (profiled) nmethods
 NonNMethod = 2, // Non-nmethods like Buffers, Adapters and Runtime Stubs
 All = 3, // All types (No code cache segmentation)
 NumTypes = 4// Number of CodeBlobTypes
};

// CodeBlob - superclass for all entries in the CodeCache.
//
// Subtypes are:
// nmethod : JIT Compiled Java methods
// RuntimeBlob : Non-compiled method code; generated glue code
// BufferBlob : Used for non-relocatable code such as interpreter, stubroutines, etc.
// AdapterBlob : Used to hold C2I/I2C adapters
// VtableBlob : Used for holding vtable chunks
// MethodHandlesAdapterBlob : Used to hold MethodHandles adapters
// RuntimeStub : Call to VM runtime methods
// SingletonBlob : Super-class for all blobs that exist in only one instance
// DeoptimizationBlob : Used for deoptimization
// SafepointBlob : Used to handle illegal instruction exceptions
// ExceptionBlob : Used for stack unrolling
// UncommonTrapBlob : Used to handle uncommon traps
// UpcallStub : Used for upcalls from native code
//
//
// Layout in the CodeCache:
// - header
// - content space
// - instruction space
// Outside of the CodeCache:
// - mutable_data
// - relocation info
// - additional data for subclasses

enumclassCodeBlobKind : u1 {
 None,
 Nmethod,
 Buffer,
 Adapter,
 Vtable,
 MHAdapter,
 RuntimeStub,
 Deoptimization,
 Safepoint,
#ifdef COMPILER2
 Exception,
 UncommonTrap,
#endif
 Upcall,
 Number_Of_Kinds
};

classUpcallStub; // for as_upcall_stub()
classRuntimeStub; // for as_runtime_stub()
classJavaFrameAnchor; // for UpcallStub::jfa_for_frame

classCodeBlob {
friendclassVMStructs;
friendclassJVMCIVMStructs;

protected:
// order fields from large to small to minimize padding between fields
 ImmutableOopMapSet* _oop_maps; // OopMap for this CodeBlob
constchar* _name;
 address _mutable_data;

int _size; // total size of CodeBlob in bytes
int _relocation_size; // size of relocation (could be bigger than 64Kb)
int _content_offset; // offset to where content region begins (this includes consts, insts, stubs)
int _code_offset; // offset to where instructions region begins (this includes insts, stubs)
int _data_offset; // offset to where data region begins
int _frame_size; // size of stack frame in words (NOT slots. On x64 these are 64bit words)
int _mutable_data_size;

S390_ONLY(int _ctable_offset;)

uint16_t _header_size; // size of header (depends on subclass)
int16_t _frame_complete_offset; // instruction offsets in [0.._frame_complete_offset) have
// not finished setting up their frame. Beware of pc's in
// that range. There is a similar range(s) on returns
// which we don't detect.

 CodeBlobKind _kind; // Kind of this code blob

bool _caller_must_gc_arguments;

#ifndef PRODUCT
 AsmRemarks _asm_remarks;
 DbgStrings _dbg_strings;
#endif

voidprint_on_impl(outputStream* st) const;
voidprint_value_on_impl(outputStream* st) const;

classVptr {
public:
virtualvoidprint_on(const CodeBlob* instance, outputStream* st) const = 0;
virtualvoidprint_value_on(const CodeBlob* instance, outputStream* st) const = 0;
 };

const Vptr* vptr() const;

CodeBlob(constchar* name, CodeBlobKind kind, CodeBuffer* cb, int size, uint16_t header_size,
int16_t frame_complete_offset, int frame_size, OopMapSet* oop_maps, bool caller_must_gc_arguments,
int mutable_data_size);

// Simple CodeBlob used for simple BufferBlob.
CodeBlob(constchar* name, CodeBlobKind kind, int size, uint16_t header_size);

voidoperatordelete(void* p) { }

public:

~CodeBlob() {
assert(_oop_maps == nullptr, "Not flushed");
 }

// Returns the space needed for CodeBlob
staticunsignedintallocation_size(CodeBuffer* cb, int header_size);
staticunsignedintalign_code_offset(int offset);

// Deletion
voidpurge();

// Typing
boolis_nmethod() const { return _kind == CodeBlobKind::Nmethod; }
boolis_buffer_blob() const { return _kind == CodeBlobKind::Buffer; }
boolis_runtime_stub() const { return _kind == CodeBlobKind::RuntimeStub; }
boolis_deoptimization_stub() const { return _kind == CodeBlobKind::Deoptimization; }
#ifdef COMPILER2
boolis_uncommon_trap_stub() const { return _kind == CodeBlobKind::UncommonTrap; }
boolis_exception_stub() const { return _kind == CodeBlobKind::Exception; }
#else
boolis_uncommon_trap_stub() const { returnfalse; }
boolis_exception_stub() const { returnfalse; }
#endif
boolis_safepoint_stub() const { return _kind == CodeBlobKind::Safepoint; }
boolis_adapter_blob() const { return _kind == CodeBlobKind::Adapter; }
boolis_vtable_blob() const { return _kind == CodeBlobKind::Vtable; }
boolis_method_handles_adapter_blob() const { return _kind == CodeBlobKind::MHAdapter; }
boolis_upcall_stub() const { return _kind == CodeBlobKind::Upcall; }

// Casting
 nmethod* as_nmethod_or_null() const { returnis_nmethod() ? (nmethod*) this : nullptr; }
 nmethod* as_nmethod() const { assert(is_nmethod(), "must be nmethod"); return (nmethod*) this; }
 CodeBlob* as_codeblob() const { return (CodeBlob*) this; }
 UpcallStub* as_upcall_stub() const { assert(is_upcall_stub(), "must be upcall stub"); return (UpcallStub*) this; }
 RuntimeStub* as_runtime_stub() const { assert(is_runtime_stub(), "must be runtime blob"); return (RuntimeStub*) this; }

// Boundaries
 address header_begin() const { return (address) this; }
 address header_end() const { return ((address) this) + _header_size; }
 address content_begin() const { return (address) header_begin() + _content_offset; }
 address content_end() const { return (address) header_begin() + _data_offset; }
 address code_begin() const { return (address) header_begin() + _code_offset; }
 address code_end() const { return (address) header_begin() + _data_offset; }
 address data_begin() const { return (address) header_begin() + _data_offset; }
 address data_end() const { return (address) header_begin() + _size; }
 address blob_end() const { return (address) header_begin() + _size; }
// code_end == content_end is true for all types of blobs for now, it is also checked in the constructor

intmutable_data_size() const { return _mutable_data_size; }
 address mutable_data_begin() const { return _mutable_data; }
 address mutable_data_end() const { return _mutable_data + _mutable_data_size; }

 relocInfo* relocation_begin() const { return (relocInfo*)_mutable_data; }
 relocInfo* relocation_end() const { return (relocInfo*)((address)relocation_begin() + _relocation_size); }

// Offsets
intcontent_offset() const { return _content_offset; }
intcode_offset() const { return _code_offset; }

// This field holds the beginning of the const section in the old code buffer.
// It is needed to fix relocations of pc-relative loads when resizing the
// the constant pool or moving it.
S390_ONLY(address ctable_begin() const { returnheader_begin() + _ctable_offset; })
voidset_ctable_begin(address ctable) { S390_ONLY(_ctable_offset = ctable - header_begin();) }

// Sizes
intsize() const { return _size; }
intheader_size() const { return _header_size; }
intrelocation_size() const { returnpointer_delta_as_int((address) relocation_end(), (address) relocation_begin()); }
intcontent_size() const { returnpointer_delta_as_int(content_end(), content_begin()); }
intcode_size() const { returnpointer_delta_as_int(code_end(), code_begin()); }

// Only used from CodeCache::free_unused_tail() after the Interpreter blob was trimmed
voidadjust_size(size_t used) {
 _size = (int)used;
 _data_offset = _size;
 }

// Containment
boolblob_contains(address addr) const { returnheader_begin() <= addr && addr < blob_end(); }
boolcode_contains(address addr) const { returncode_begin() <= addr && addr < code_end(); }
boolcontains(address addr) const { returncontent_begin() <= addr && addr < content_end(); }
boolis_frame_complete_at(address addr) const { return _frame_complete_offset != CodeOffsets::frame_never_safe &&
code_contains(addr) && addr >= code_begin() + _frame_complete_offset; }
intframe_complete_offset() const { return _frame_complete_offset; }

// OopMap for frame
 ImmutableOopMapSet* oop_maps() const { return _oop_maps; }
voidset_oop_maps(OopMapSet* p);

const ImmutableOopMap* oop_map_for_slot(int slot, address return_address) const;
const ImmutableOopMap* oop_map_for_return_address(address return_address) const;

// Frame support. Sizes are in word units.
intframe_size() const { return _frame_size; }
voidset_frame_size(int size) { _frame_size = size; }

// Returns true, if the next frame is responsible for GC'ing oops passed as arguments
boolcaller_must_gc_arguments(JavaThread* thread) const { return _caller_must_gc_arguments; }

// Naming
constchar* name() const { return _name; }
voidset_name(constchar* name) { _name = name; }

// Debugging
voidverify();
voidprint() const;
voidprint_on(outputStream* st) const;
voidprint_value_on(outputStream* st) const;

voiddump_for_addr(address addr, outputStream* st, bool verbose) const;
voidprint_code_on(outputStream* st);

// Print to stream, any comments associated with offset.
voidprint_block_comment(outputStream* stream, address block_begin) const;

#ifndef PRODUCT
 AsmRemarks &asm_remarks() { return _asm_remarks; }
 DbgStrings &dbg_strings() { return _dbg_strings; }

voiduse_remarks(AsmRemarks &remarks) { _asm_remarks.share(remarks); }
voiduse_strings(DbgStrings &strings) { _dbg_strings.share(strings); }
#endif
};

//----------------------------------------------------------------------------------------------------
// RuntimeBlob: used for non-compiled method code (adapters, stubs, blobs)

classRuntimeBlob : publicCodeBlob {
friendclassVMStructs;
public:

// Creation
// a) simple CodeBlob
RuntimeBlob(constchar* name, CodeBlobKind kind, int size, uint16_t header_size)
 : CodeBlob(name, kind, size, header_size)
 {}

// b) full CodeBlob
// frame_complete is the offset from the beginning of the instructions
// to where the frame setup (from stackwalk viewpoint) is complete.
RuntimeBlob(
constchar* name,
 CodeBlobKind kind,
 CodeBuffer* cb,
int size,
uint16_t header_size,
int16_t frame_complete,
int frame_size,
 OopMapSet* oop_maps,
bool caller_must_gc_arguments = false
 );

staticvoidfree(RuntimeBlob* blob);

// Deal with Disassembler, VTune, Forte, JvmtiExport, MemoryService.
staticvoidtrace_new_stub(RuntimeBlob* blob, constchar* name1, constchar* name2 = "");

classVptr : publicCodeBlob::Vptr {
 };
};

classWhiteBox;
//----------------------------------------------------------------------------------------------------
// BufferBlob: used to hold non-relocatable machine code such as the interpreter, stubroutines, etc.

classBufferBlob: publicRuntimeBlob {
friendclassVMStructs;
friendclassAdapterBlob;
friendclassVtableBlob;
friendclassMethodHandlesAdapterBlob;
friendclassUpcallStub;
friendclassWhiteBox;

private:
// Creation support
BufferBlob(constchar* name, CodeBlobKind kind, int size);
BufferBlob(constchar* name, CodeBlobKind kind, CodeBuffer* cb, int size);

void* operatornew(size_t s, unsigned size) throw();

public:
// Creation
static BufferBlob* create(constchar* name, uint buffer_size);
static BufferBlob* create(constchar* name, CodeBuffer* cb);

staticvoidfree(BufferBlob* buf);

voidprint_on_impl(outputStream* st) const;
voidprint_value_on_impl(outputStream* st) const;

classVptr : publicRuntimeBlob::Vptr {
voidprint_on(const CodeBlob* instance, outputStream* st) constoverride {
 ((const BufferBlob*)instance)->print_on_impl(st);
 }
voidprint_value_on(const CodeBlob* instance, outputStream* st) constoverride {
 ((const BufferBlob*)instance)->print_value_on_impl(st);
 }
 };

staticconst Vptr _vpntr;
};


//----------------------------------------------------------------------------------------------------
// AdapterBlob: used to hold C2I/I2C adapters

classAdapterBlob: publicBufferBlob {
private:
AdapterBlob(int size, CodeBuffer* cb);

public:
// Creation
static AdapterBlob* create(CodeBuffer* cb);
};

//---------------------------------------------------------------------------------------------------
classVtableBlob: publicBufferBlob {
private:
VtableBlob(constchar*, int);

void* operatornew(size_t s, unsigned size) throw();

public:
// Creation
static VtableBlob* create(constchar* name, int buffer_size);
};

//----------------------------------------------------------------------------------------------------
// MethodHandlesAdapterBlob: used to hold MethodHandles adapters

classMethodHandlesAdapterBlob: publicBufferBlob {
private:
MethodHandlesAdapterBlob(int size): BufferBlob("MethodHandles adapters", CodeBlobKind::MHAdapter, size) {}

public:
// Creation
static MethodHandlesAdapterBlob* create(int buffer_size);
};


//----------------------------------------------------------------------------------------------------
// RuntimeStub: describes stubs used by compiled code to call a (static) C++ runtime routine

classRuntimeStub: publicRuntimeBlob {
friendclassVMStructs;
private:
// Creation support
RuntimeStub(
constchar* name,
 CodeBuffer* cb,
int size,
int16_t frame_complete,
int frame_size,
 OopMapSet* oop_maps,
bool caller_must_gc_arguments
 );

void* operatornew(size_t s, unsigned size) throw();

public:
// Creation
static RuntimeStub* new_runtime_stub(
constchar* stub_name,
 CodeBuffer* cb,
int16_t frame_complete,
int frame_size,
 OopMapSet* oop_maps,
bool caller_must_gc_arguments,
bool alloc_fail_is_fatal=true
 );

staticvoidfree(RuntimeStub* stub) { RuntimeBlob::free(stub); }

 address entry_point() const { returncode_begin(); }

voidprint_on_impl(outputStream* st) const;
voidprint_value_on_impl(outputStream* st) const;

classVptr : publicRuntimeBlob::Vptr {
voidprint_on(const CodeBlob* instance, outputStream* st) constoverride {
 instance->as_runtime_stub()->print_on_impl(st);
 }
voidprint_value_on(const CodeBlob* instance, outputStream* st) constoverride {
 instance->as_runtime_stub()->print_value_on_impl(st);
 }
 };

staticconst Vptr _vpntr;
};


//----------------------------------------------------------------------------------------------------
// Super-class for all blobs that exist in only one instance. Implements default behaviour.

classSingletonBlob: publicRuntimeBlob {
friendclassVMStructs;

protected:
void* operatornew(size_t s, unsigned size, bool alloc_fail_is_fatal=true) throw();

public:
SingletonBlob(
constchar* name,
 CodeBlobKind kind,
 CodeBuffer* cb,
int size,
uint16_t header_size,
int frame_size,
 OopMapSet* oop_maps
 )
 : RuntimeBlob(name, kind, cb, size, header_size, CodeOffsets::frame_never_safe, frame_size, oop_maps)
 {};

 address entry_point() { returncode_begin(); }

voidprint_on_impl(outputStream* st) const;
voidprint_value_on_impl(outputStream* st) const;

classVptr : publicRuntimeBlob::Vptr {
voidprint_on(const CodeBlob* instance, outputStream* st) constoverride {
 ((const SingletonBlob*)instance)->print_on_impl(st);
 }
voidprint_value_on(const CodeBlob* instance, outputStream* st) constoverride {
 ((const SingletonBlob*)instance)->print_value_on_impl(st);
 }
 };

staticconst Vptr _vpntr;
};


//----------------------------------------------------------------------------------------------------
// DeoptimizationBlob

classDeoptimizationBlob: publicSingletonBlob {
friendclassVMStructs;
friendclassJVMCIVMStructs;
private:
int _unpack_offset;
int _unpack_with_exception;
int _unpack_with_reexecution;

int _unpack_with_exception_in_tls;

#if INCLUDE_JVMCI
// Offsets when JVMCI calls uncommon_trap.
int _uncommon_trap_offset;
int _implicit_exception_uncommon_trap_offset;
#endif

// Creation support
DeoptimizationBlob(
 CodeBuffer* cb,
int size,
 OopMapSet* oop_maps,
int unpack_offset,
int unpack_with_exception_offset,
int unpack_with_reexecution_offset,
int frame_size
 );

public:
// Creation
static DeoptimizationBlob* create(
 CodeBuffer* cb,
 OopMapSet* oop_maps,
int unpack_offset,
int unpack_with_exception_offset,
int unpack_with_reexecution_offset,
int frame_size
 );

 address unpack() const { returncode_begin() + _unpack_offset; }
 address unpack_with_exception() const { returncode_begin() + _unpack_with_exception; }
 address unpack_with_reexecution() const { returncode_begin() + _unpack_with_reexecution; }

// Alternate entry point for C1 where the exception and issuing pc
// are in JavaThread::_exception_oop and JavaThread::_exception_pc
// instead of being in registers. This is needed because C1 doesn't
// model exception paths in a way that keeps these registers free so
// there may be live values in those registers during deopt.
voidset_unpack_with_exception_in_tls_offset(int offset) {
 _unpack_with_exception_in_tls = offset;
assert(code_contains(code_begin() + _unpack_with_exception_in_tls), "must be PC inside codeblob");
 }
 address unpack_with_exception_in_tls() const { returncode_begin() + _unpack_with_exception_in_tls; }

#if INCLUDE_JVMCI
// Offsets when JVMCI calls uncommon_trap.
voidset_uncommon_trap_offset(int offset) {
 _uncommon_trap_offset = offset;
assert(contains(code_begin() + _uncommon_trap_offset), "must be PC inside codeblob");
 }
 address uncommon_trap() const { returncode_begin() + _uncommon_trap_offset; }

voidset_implicit_exception_uncommon_trap_offset(int offset) {
 _implicit_exception_uncommon_trap_offset = offset;
assert(contains(code_begin() + _implicit_exception_uncommon_trap_offset), "must be PC inside codeblob");
 }
 address implicit_exception_uncommon_trap() const { returncode_begin() + _implicit_exception_uncommon_trap_offset; }
#endif// INCLUDE_JVMCI

voidprint_value_on_impl(outputStream* st) const;

classVptr : publicSingletonBlob::Vptr {
voidprint_value_on(const CodeBlob* instance, outputStream* st) constoverride {
 ((const DeoptimizationBlob*)instance)->print_value_on_impl(st);
 }
 };

staticconst Vptr _vpntr;
};


//----------------------------------------------------------------------------------------------------
// UncommonTrapBlob (currently only used by Compiler 2)

#ifdef COMPILER2

classUncommonTrapBlob: publicSingletonBlob {
friendclassVMStructs;
private:
// Creation support
UncommonTrapBlob(
 CodeBuffer* cb,
int size,
 OopMapSet* oop_maps,
int frame_size
 );

public:
// Creation
static UncommonTrapBlob* create(
 CodeBuffer* cb,
 OopMapSet* oop_maps,
int frame_size
 );
};


//----------------------------------------------------------------------------------------------------
// ExceptionBlob: used for exception unwinding in compiled code (currently only used by Compiler 2)

classExceptionBlob: publicSingletonBlob {
friendclassVMStructs;
private:
// Creation support
ExceptionBlob(
 CodeBuffer* cb,
int size,
 OopMapSet* oop_maps,
int frame_size
 );

public:
// Creation
static ExceptionBlob* create(
 CodeBuffer* cb,
 OopMapSet* oop_maps,
int frame_size
 );
};
#endif// COMPILER2


//----------------------------------------------------------------------------------------------------
// SafepointBlob: handles illegal_instruction exceptions during a safepoint

classSafepointBlob: publicSingletonBlob {
friendclassVMStructs;
private:
// Creation support
SafepointBlob(
 CodeBuffer* cb,
int size,
 OopMapSet* oop_maps,
int frame_size
 );

public:
// Creation
static SafepointBlob* create(
 CodeBuffer* cb,
 OopMapSet* oop_maps,
int frame_size
 );
};

//----------------------------------------------------------------------------------------------------

classUpcallLinker;

// A (Panama) upcall stub. Not used by JNI.
classUpcallStub: publicRuntimeBlob {
friendclassVMStructs;
friendclassUpcallLinker;
private:
 jobject _receiver;
 ByteSize _frame_data_offset;

UpcallStub(constchar* name, CodeBuffer* cb, int size, jobject receiver, ByteSize frame_data_offset);

void* operatornew(size_t s, unsigned size) throw();

structFrameData {
 JavaFrameAnchor jfa;
 JavaThread* thread;
 JNIHandleBlock* old_handles;
 JNIHandleBlock* new_handles;
 };

// defined in frame_ARCH.cpp
 FrameData* frame_data_for_frame(const frame& frame) const;
public:
// Creation
static UpcallStub* create(constchar* name, CodeBuffer* cb, jobject receiver, ByteSize frame_data_offset);

staticvoidfree(UpcallStub* blob);

 jobject receiver() { return _receiver; }

 JavaFrameAnchor* jfa_for_frame(const frame& frame) const;

// GC support
voidoops_do(OopClosure* f, const frame& frame);

voidprint_on_impl(outputStream* st) const;
voidprint_value_on_impl(outputStream* st) const;

classVptr : publicRuntimeBlob::Vptr {
voidprint_on(const CodeBlob* instance, outputStream* st) constoverride {
 instance->as_upcall_stub()->print_on_impl(st);
 }
voidprint_value_on(const CodeBlob* instance, outputStream* st) constoverride {
 instance->as_upcall_stub()->print_value_on_impl(st);
 }
 };

staticconst Vptr _vpntr;
};

#endif// SHARE_CODE_CODEBLOB_HPP