// Copyright (c) 1994-2006 Sun Microsystems Inc.
// All Rights Reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// - Redistributions of source code must retain the above copyright notice,
// this list of conditions and the following disclaimer.
//
// - Redistribution in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the distribution.
//
// - Neither the name of Sun Microsystems or the names of contributors may
// be used to endorse or promote products derived from this software without
// specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
// IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
// THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
// PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
// CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
// EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
// LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
// NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// The original source code covered by the above license above has been
// modified significantly by Google Inc.
// Copyright 2012 the V8 project authors. All rights reserved.
#ifndef V8_ASSEMBLER_H_
#define V8_ASSEMBLER_H_
#include "src/v8.h"
#include "src/allocation.h"
#include "src/builtins.h"
#include "src/gdb-jit.h"
#include "src/isolate.h"
#include "src/runtime.h"
#include "src/token.h"
namespace v8 {
class ApiFunction;
namespace internal {
class StatsCounter;
// -----------------------------------------------------------------------------
// Platform independent assembler base class.
class AssemblerBase: public Malloced {
public:
AssemblerBase(Isolate* isolate, void* buffer, int buffer_size);
virtual ~AssemblerBase();
Isolate* isolate() const { return isolate_; }
int jit_cookie() const { return jit_cookie_; }
bool emit_debug_code() const { return emit_debug_code_; }
void set_emit_debug_code(bool value) { emit_debug_code_ = value; }
bool serializer_enabled() const { return serializer_enabled_; }
void enable_serializer() { serializer_enabled_ = true; }
bool predictable_code_size() const { return predictable_code_size_; }
void set_predictable_code_size(bool value) { predictable_code_size_ = value; }
uint64_t enabled_cpu_features() const { return enabled_cpu_features_; }
void set_enabled_cpu_features(uint64_t features) {
enabled_cpu_features_ = features;
}
bool IsEnabled(CpuFeature f) {
return (enabled_cpu_features_ & (static_cast<uint64_t>(1) << f)) != 0;
}
// Overwrite a host NaN with a quiet target NaN. Used by mksnapshot for
// cross-snapshotting.
static void QuietNaN(HeapObject* nan) { }
int pc_offset() const { return static_cast<int>(pc_ - buffer_); }
// This function is called when code generation is aborted, so that
// the assembler could clean up internal data structures.
virtual void AbortedCodeGeneration() { }
static const int kMinimalBufferSize = 4*KB;
protected:
// The buffer into which code and relocation info are generated. It could
// either be owned by the assembler or be provided externally.
byte* buffer_;
int buffer_size_;
bool own_buffer_;
// The program counter, which points into the buffer above and moves forward.
byte* pc_;
private:
Isolate* isolate_;
int jit_cookie_;
uint64_t enabled_cpu_features_;
bool emit_debug_code_;
bool predictable_code_size_;
bool serializer_enabled_;
};
// Avoids emitting debug code during the lifetime of this scope object.
class DontEmitDebugCodeScope BASE_EMBEDDED {
public:
explicit DontEmitDebugCodeScope(AssemblerBase* assembler)
: assembler_(assembler), old_value_(assembler->emit_debug_code()) {
assembler_->set_emit_debug_code(false);
}
~DontEmitDebugCodeScope() {
assembler_->set_emit_debug_code(old_value_);
}
private:
AssemblerBase* assembler_;
bool old_value_;
};
// Avoids using instructions that vary in size in unpredictable ways between the
// snapshot and the running VM.
class PredictableCodeSizeScope {
public:
PredictableCodeSizeScope(AssemblerBase* assembler, int expected_size);
~PredictableCodeSizeScope();
private:
AssemblerBase* assembler_;
int expected_size_;
int start_offset_;
bool old_value_;
};
// Enable a specified feature within a scope.
class CpuFeatureScope BASE_EMBEDDED {
public:
#ifdef DEBUG
CpuFeatureScope(AssemblerBase* assembler, CpuFeature f);
~CpuFeatureScope();
private:
AssemblerBase* assembler_;
uint64_t old_enabled_;
#else
CpuFeatureScope(AssemblerBase* assembler, CpuFeature f) {}
#endif
};
// CpuFeatures keeps track of which features are supported by the target CPU.
// Supported features must be enabled by a CpuFeatureScope before use.
// Example:
// if (assembler->IsSupported(SSE3)) {
// CpuFeatureScope fscope(assembler, SSE3);
// // Generate code containing SSE3 instructions.
// } else {
// // Generate alternative code.
// }
class CpuFeatures : public AllStatic {
public:
static void Probe(bool cross_compile) {
STATIC_ASSERT(NUMBER_OF_CPU_FEATURES <= kBitsPerInt);
if (initialized_) return;
initialized_ = true;
ProbeImpl(cross_compile);
}
static unsigned SupportedFeatures() {
Probe(false);
return supported_;
}
static bool IsSupported(CpuFeature f) {
return (supported_ & (1u << f)) != 0;
}
static inline bool SupportsCrankshaft();
static inline unsigned cache_line_size() {
DCHECK(cache_line_size_ != 0);
return cache_line_size_;
}
static void PrintTarget();
static void PrintFeatures();
// Flush instruction cache.
static void FlushICache(void* start, size_t size);
private:
// Platform-dependent implementation.
static void ProbeImpl(bool cross_compile);
static unsigned supported_;
static unsigned cache_line_size_;
static bool initialized_;
friend class ExternalReference;
DISALLOW_COPY_AND_ASSIGN(CpuFeatures);
};
// -----------------------------------------------------------------------------
// Labels represent pc locations; they are typically jump or call targets.
// After declaration, a label can be freely used to denote known or (yet)
// unknown pc location. Assembler::bind() is used to bind a label to the
// current pc. A label can be bound only once.
class Label BASE_EMBEDDED {
public:
enum Distance {
kNear, kFar
};
INLINE(Label()) {
Unuse();
UnuseNear();
}
INLINE(~Label()) {
DCHECK(!is_linked());
DCHECK(!is_near_linked());
}
INLINE(void Unuse()) { pos_ = 0; }
INLINE(void UnuseNear()) { near_link_pos_ = 0; }
INLINE(bool is_bound() const) { return pos_ < 0; }
INLINE(bool is_unused() const) { return pos_ == 0 && near_link_pos_ == 0; }
INLINE(bool is_linked() const) { return pos_ > 0; }
INLINE(bool is_near_linked() const) { return near_link_pos_ > 0; }
// Returns the position of bound or linked labels. Cannot be used
// for unused labels.
int pos() const;
int near_link_pos() const { return near_link_pos_ - 1; }
private:
// pos_ encodes both the binding state (via its sign)
// and the binding position (via its value) of a label.
//
// pos_ < 0 bound label, pos() returns the jump target position
// pos_ == 0 unused label
// pos_ > 0 linked label, pos() returns the last reference position
int pos_;
// Behaves like |pos_| in the "> 0" case, but for near jumps to this label.
int near_link_pos_;
void bind_to(int pos) {
pos_ = -pos - 1;
DCHECK(is_bound());
}
void link_to(int pos, Distance distance = kFar) {
if (distance == kNear) {
near_link_pos_ = pos + 1;
DCHECK(is_near_linked());
} else {
pos_ = pos + 1;
DCHECK(is_linked());
}
}
friend class Assembler;
friend class Displacement;
friend class RegExpMacroAssemblerIrregexp;
#if V8_TARGET_ARCH_ARM64
// On ARM64, the Assembler keeps track of pointers to Labels to resolve
// branches to distant targets. Copying labels would confuse the Assembler.
DISALLOW_COPY_AND_ASSIGN(Label); // NOLINT
#endif
};
enum SaveFPRegsMode { kDontSaveFPRegs, kSaveFPRegs };
// Specifies whether to perform icache flush operations on RelocInfo updates.
// If FLUSH_ICACHE_IF_NEEDED, the icache will always be flushed if an
// instruction was modified. If SKIP_ICACHE_FLUSH the flush will always be
// skipped (only use this if you will flush the icache manually before it is
// executed).
enum ICacheFlushMode { FLUSH_ICACHE_IF_NEEDED, SKIP_ICACHE_FLUSH };
// -----------------------------------------------------------------------------
// Relocation information
// Relocation information consists of the address (pc) of the datum
// to which the relocation information applies, the relocation mode
// (rmode), and an optional data field. The relocation mode may be
// "descriptive" and not indicate a need for relocation, but simply
// describe a property of the datum. Such rmodes are useful for GC
// and nice disassembly output.
class RelocInfo {
public:
// The constant kNoPosition is used with the collecting of source positions
// in the relocation information. Two types of source positions are collected
// "position" (RelocMode position) and "statement position" (RelocMode
// statement_position). The "position" is collected at places in the source
// code which are of interest when making stack traces to pin-point the source
// location of a stack frame as close as possible. The "statement position" is
// collected at the beginning at each statement, and is used to indicate
// possible break locations. kNoPosition is used to indicate an
// invalid/uninitialized position value.
static const int kNoPosition = -1;
// This string is used to add padding comments to the reloc info in cases
// where we are not sure to have enough space for patching in during
// lazy deoptimization. This is the case if we have indirect calls for which
// we do not normally record relocation info.
static const char* const kFillerCommentString;
// The minimum size of a comment is equal to three bytes for the extra tagged
// pc + the tag for the data, and kPointerSize for the actual pointer to the
// comment.
static const int kMinRelocCommentSize = 3 + kPointerSize;
// The maximum size for a call instruction including pc-jump.
static const int kMaxCallSize = 6;
// The maximum pc delta that will use the short encoding.
static const int kMaxSmallPCDelta;
enum Mode {
// Please note the order is important (see IsCodeTarget, IsGCRelocMode).
CODE_TARGET, // Code target which is not any of the above.
CODE_TARGET_WITH_ID,
CONSTRUCT_CALL, // code target that is a call to a JavaScript constructor.
DEBUG_BREAK, // Code target for the debugger statement.
EMBEDDED_OBJECT,
CELL,
// Everything after runtime_entry (inclusive) is not GC'ed.
RUNTIME_ENTRY,
JS_RETURN, // Marks start of the ExitJSFrame code.
COMMENT,
POSITION, // See comment for kNoPosition above.
STATEMENT_POSITION, // See comment for kNoPosition above.
DEBUG_BREAK_SLOT, // Additional code inserted for debug break slot.
EXTERNAL_REFERENCE, // The address of an external C++ function.
INTERNAL_REFERENCE, // An address inside the same function.
// Marks constant and veneer pools. Only used on ARM and ARM64.
// They use a custom noncompact encoding.
CONST_POOL,
VENEER_POOL,
// add more as needed
// Pseudo-types
NUMBER_OF_MODES, // There are at most 15 modes with noncompact encoding.
NONE32, // never recorded 32-bit value
NONE64, // never recorded 64-bit value
CODE_AGE_SEQUENCE, // Not stored in RelocInfo array, used explictly by
// code aging.
FIRST_REAL_RELOC_MODE = CODE_TARGET,
LAST_REAL_RELOC_MODE = VENEER_POOL,
FIRST_PSEUDO_RELOC_MODE = CODE_AGE_SEQUENCE,
LAST_PSEUDO_RELOC_MODE = CODE_AGE_SEQUENCE,
LAST_CODE_ENUM = DEBUG_BREAK,
LAST_GCED_ENUM = CELL,
// Modes <= LAST_COMPACT_ENUM are guaranteed to have compact encoding.
LAST_COMPACT_ENUM = CODE_TARGET_WITH_ID,
LAST_STANDARD_NONCOMPACT_ENUM = INTERNAL_REFERENCE
};
RelocInfo() {}
RelocInfo(byte* pc, Mode rmode, intptr_t data, Code* host)
: pc_(pc), rmode_(rmode), data_(data), host_(host) {
}
RelocInfo(byte* pc, double data64)
: pc_(pc), rmode_(NONE64), data64_(data64), host_(NULL) {
}
static inline bool IsRealRelocMode(Mode mode) {
return mode >= FIRST_REAL_RELOC_MODE &&
mode <= LAST_REAL_RELOC_MODE;
}
static inline bool IsPseudoRelocMode(Mode mode) {
DCHECK(!IsRealRelocMode(mode));
return mode >= FIRST_PSEUDO_RELOC_MODE &&
mode <= LAST_PSEUDO_RELOC_MODE;
}
static inline bool IsConstructCall(Mode mode) {
return mode == CONSTRUCT_CALL;
}
static inline bool IsCodeTarget(Mode mode) {
return mode <= LAST_CODE_ENUM;
}
static inline bool IsEmbeddedObject(Mode mode) {
return mode == EMBEDDED_OBJECT;
}
static inline bool IsRuntimeEntry(Mode mode) {
return mode == RUNTIME_ENTRY;
}
// Is the relocation mode affected by GC?
static inline bool IsGCRelocMode(Mode mode) {
return mode <= LAST_GCED_ENUM;
}
static inline bool IsJSReturn(Mode mode) {
return mode == JS_RETURN;
}
static inline bool IsComment(Mode mode) {
return mode == COMMENT;
}
static inline bool IsConstPool(Mode mode) {
return mode == CONST_POOL;
}
static inline bool IsVeneerPool(Mode mode) {
return mode == VENEER_POOL;
}
static inline bool IsPosition(Mode mode) {
return mode == POSITION || mode == STATEMENT_POSITION;
}
static inline bool IsStatementPosition(Mode mode) {
return mode == STATEMENT_POSITION;
}
static inline bool IsExternalReference(Mode mode) {
return mode == EXTERNAL_REFERENCE;
}
static inline bool IsInternalReference(Mode mode) {
return mode == INTERNAL_REFERENCE;
}
static inline bool IsDebugBreakSlot(Mode mode) {
return mode == DEBUG_BREAK_SLOT;
}
static inline bool IsNone(Mode mode) {
return mode == NONE32 || mode == NONE64;
}
static inline bool IsCodeAgeSequence(Mode mode) {
return mode == CODE_AGE_SEQUENCE;
}
static inline int ModeMask(Mode mode) { return 1 << mode; }
// Returns true if the first RelocInfo has the same mode and raw data as the
// second one.
static inline bool IsEqual(RelocInfo first, RelocInfo second) {
return first.rmode() == second.rmode() &&
(first.rmode() == RelocInfo::NONE64 ?
first.raw_data64() == second.raw_data64() :
first.data() == second.data());
}
// Accessors
byte* pc() const { return pc_; }
void set_pc(byte* pc) { pc_ = pc; }
Mode rmode() const { return rmode_; }
intptr_t data() const { return data_; }
double data64() const { return data64_; }
uint64_t raw_data64() { return bit_cast<uint64_t>(data64_); }
Code* host() const { return host_; }
void set_host(Code* host) { host_ = host; }
// Apply a relocation by delta bytes
INLINE(void apply(intptr_t delta,
ICacheFlushMode icache_flush_mode =
FLUSH_ICACHE_IF_NEEDED));
// Is the pointer this relocation info refers to coded like a plain pointer
// or is it strange in some way (e.g. relative or patched into a series of
// instructions).
bool IsCodedSpecially();
// If true, the pointer this relocation info refers to is an entry in the
// constant pool, otherwise the pointer is embedded in the instruction stream.
bool IsInConstantPool();
// Read/modify the code target in the branch/call instruction
// this relocation applies to;
// can only be called if IsCodeTarget(rmode_) || IsRuntimeEntry(rmode_)
INLINE(Address target_address());
INLINE(void set_target_address(Address target,
WriteBarrierMode write_barrier_mode =
UPDATE_WRITE_BARRIER,
ICacheFlushMode icache_flush_mode =
FLUSH_ICACHE_IF_NEEDED));
INLINE(Object* target_object());
INLINE(Handle<Object> target_object_handle(Assembler* origin));
INLINE(void set_target_object(Object* target,
WriteBarrierMode write_barrier_mode =
UPDATE_WRITE_BARRIER,
ICacheFlushMode icache_flush_mode =
FLUSH_ICACHE_IF_NEEDED));
INLINE(Address target_runtime_entry(Assembler* origin));
INLINE(void set_target_runtime_entry(Address target,
WriteBarrierMode write_barrier_mode =
UPDATE_WRITE_BARRIER,
ICacheFlushMode icache_flush_mode =
FLUSH_ICACHE_IF_NEEDED));
INLINE(Cell* target_cell());
INLINE(Handle<Cell> target_cell_handle());
INLINE(void set_target_cell(Cell* cell,
WriteBarrierMode write_barrier_mode =
UPDATE_WRITE_BARRIER,
ICacheFlushMode icache_flush_mode =
FLUSH_ICACHE_IF_NEEDED));
INLINE(Handle<Object> code_age_stub_handle(Assembler* origin));
INLINE(Code* code_age_stub());
INLINE(void set_code_age_stub(Code* stub,
ICacheFlushMode icache_flush_mode =
FLUSH_ICACHE_IF_NEEDED));
// Returns the address of the constant pool entry where the target address
// is held. This should only be called if IsInConstantPool returns true.
INLINE(Address constant_pool_entry_address());
// Read the address of the word containing the target_address in an
// instruction stream. What this means exactly is architecture-independent.
// The only architecture-independent user of this function is the serializer.
// The serializer uses it to find out how many raw bytes of instruction to
// output before the next target. Architecture-independent code shouldn't
// dereference the pointer it gets back from this.
INLINE(Address target_address_address());
// This indicates how much space a target takes up when deserializing a code
// stream. For most architectures this is just the size of a pointer. For
// an instruction like movw/movt where the target bits are mixed into the
// instruction bits the size of the target will be zero, indicating that the
// serializer should not step forwards in memory after a target is resolved
// and written. In this case the target_address_address function above
// should return the end of the instructions to be patched, allowing the
// deserializer to deserialize the instructions as raw bytes and put them in
// place, ready to be patched with the target.
INLINE(int target_address_size());
// Read/modify the reference in the instruction this relocation
// applies to; can only be called if rmode_ is external_reference
INLINE(Address target_reference());
// Read/modify the address of a call instruction. This is used to relocate
// the break points where straight-line code is patched with a call
// instruction.
INLINE(Address call_address());
INLINE(void set_call_address(Address target));
INLINE(Object* call_object());
INLINE(void set_call_object(Object* target));
INLINE(Object** call_object_address());
// Wipe out a relocation to a fixed value, used for making snapshots
// reproducible.
INLINE(void WipeOut());
template<typename StaticVisitor> inline void Visit(Heap* heap);
inline void Visit(Isolate* isolate, ObjectVisitor* v);
// Patch the code with some other code.
void PatchCode(byte* instructions, int instruction_count);
// Patch the code with a call.
void PatchCodeWithCall(Address target, int guard_bytes);
// Check whether this return sequence has been patched
// with a call to the debugger.
INLINE(bool IsPatchedReturnSequence());
// Check whether this debug break slot has been patched with a call to the
// debugger.
INLINE(bool IsPatchedDebugBreakSlotSequence());
#ifdef DEBUG
// Check whether the given code contains relocation information that
// either is position-relative or movable by the garbage collector.
static bool RequiresRelocation(const CodeDesc& desc);
#endif
#ifdef ENABLE_DISASSEMBLER
// Printing
static const char* RelocModeName(Mode rmode);
void Print(Isolate* isolate, OStream& os); // NOLINT
#endif // ENABLE_DISASSEMBLER
#ifdef VERIFY_HEAP
void Verify(Isolate* isolate);
#endif
static const int kCodeTargetMask = (1 << (LAST_CODE_ENUM + 1)) - 1;
static const int kPositionMask = 1 << POSITION | 1 << STATEMENT_POSITION;
static const int kDataMask =
(1 << CODE_TARGET_WITH_ID) | kPositionMask | (1 << COMMENT);
static const int kApplyMask; // Modes affected by apply. Depends on arch.
private:
// On ARM, note that pc_ is the address of the constant pool entry
// to be relocated and not the address of the instruction
// referencing the constant pool entry (except when rmode_ ==
// comment).
byte* pc_;
Mode rmode_;
union {
intptr_t data_;
double data64_;
};
Code* host_;
// External-reference pointers are also split across instruction-pairs
// on some platforms, but are accessed via indirect pointers. This location
// provides a place for that pointer to exist naturally. Its address
// is returned by RelocInfo::target_reference_address().
Address reconstructed_adr_ptr_;
friend class RelocIterator;
};
// RelocInfoWriter serializes a stream of relocation info. It writes towards
// lower addresses.
class RelocInfoWriter BASE_EMBEDDED {
public:
RelocInfoWriter() : pos_(NULL),
last_pc_(NULL),
last_id_(0),
last_position_(0) {}
RelocInfoWriter(byte* pos, byte* pc) : pos_(pos),
last_pc_(pc),
last_id_(0),
last_position_(0) {}
byte* pos() const { return pos_; }
byte* last_pc() const { return last_pc_; }
void Write(const RelocInfo* rinfo);
// Update the state of the stream after reloc info buffer
// and/or code is moved while the stream is active.
void Reposition(byte* pos, byte* pc) {
pos_ = pos;
last_pc_ = pc;
}
// Max size (bytes) of a written RelocInfo. Longest encoding is
// ExtraTag, VariableLengthPCJump, ExtraTag, pc_delta, ExtraTag, data_delta.
// On ia32 and arm this is 1 + 4 + 1 + 1 + 1 + 4 = 12.
// On x64 this is 1 + 4 + 1 + 1 + 1 + 8 == 16;
// Here we use the maximum of the two.
static const int kMaxSize = 16;
private:
inline uint32_t WriteVariableLengthPCJump(uint32_t pc_delta);
inline void WriteTaggedPC(uint32_t pc_delta, int tag);
inline void WriteExtraTaggedPC(uint32_t pc_delta, int extra_tag);
inline void WriteExtraTaggedIntData(int data_delta, int top_tag);
inline void WriteExtraTaggedPoolData(int data, int pool_type);
inline void WriteExtraTaggedData(intptr_t data_delta, int top_tag);
inline void WriteTaggedData(intptr_t data_delta, int tag);
inline void WriteExtraTag(int extra_tag, int top_tag);
byte* pos_;
byte* last_pc_;
int last_id_;
int last_position_;
DISALLOW_COPY_AND_ASSIGN(RelocInfoWriter);
};
// A RelocIterator iterates over relocation information.
// Typical use:
//
// for (RelocIterator it(code); !it.done(); it.next()) {
// // do something with it.rinfo() here
// }
//
// A mask can be specified to skip unwanted modes.
class RelocIterator: public Malloced {
public:
// Create a new iterator positioned at
// the beginning of the reloc info.
// Relocation information with mode k is included in the
// iteration iff bit k of mode_mask is set.
explicit RelocIterator(Code* code, int mode_mask = -1);
explicit RelocIterator(const CodeDesc& desc, int mode_mask = -1);
// Iteration
bool done() const { return done_; }
void next();
// Return pointer valid until next next().
RelocInfo* rinfo() {
DCHECK(!done());
return &rinfo_;
}
private:
// Advance* moves the position before/after reading.
// *Read* reads from current byte(s) into rinfo_.
// *Get* just reads and returns info on current byte.
void Advance(int bytes = 1) { pos_ -= bytes; }
int AdvanceGetTag();
int GetExtraTag();
int GetTopTag();
void ReadTaggedPC();
void AdvanceReadPC();
void AdvanceReadId();
void AdvanceReadPoolData();
void AdvanceReadPosition();
void AdvanceReadData();
void AdvanceReadVariableLengthPCJump();
int GetLocatableTypeTag();
void ReadTaggedId();
void ReadTaggedPosition();
// If the given mode is wanted, set it in rinfo_ and return true.
// Else return false. Used for efficiently skipping unwanted modes.
bool SetMode(RelocInfo::Mode mode) {
return (mode_mask_ & (1 << mode)) ? (rinfo_.rmode_ = mode, true) : false;
}
byte* pos_;
byte* end_;
byte* code_age_sequence_;
RelocInfo rinfo_;
bool done_;
int mode_mask_;
int last_id_;
int last_position_;
DISALLOW_COPY_AND_ASSIGN(RelocIterator);
};
//------------------------------------------------------------------------------
// External function
//----------------------------------------------------------------------------
class IC_Utility;
class SCTableReference;
class Debug_Address;
// An ExternalReference represents a C++ address used in the generated
// code. All references to C++ functions and variables must be encapsulated in
// an ExternalReference instance. This is done in order to track the origin of
// all external references in the code so that they can be bound to the correct
// addresses when deserializing a heap.
class ExternalReference BASE_EMBEDDED {
public:
// Used in the simulator to support different native api calls.
enum Type {
// Builtin call.
// Object* f(v8::internal::Arguments).
BUILTIN_CALL, // default
// Builtin that takes float arguments and returns an int.
// int f(double, double).
BUILTIN_COMPARE_CALL,
// Builtin call that returns floating point.
// double f(double, double).
BUILTIN_FP_FP_CALL,
// Builtin call that returns floating point.
// double f(double).
BUILTIN_FP_CALL,
// Builtin call that returns floating point.
// double f(double, int).
BUILTIN_FP_INT_CALL,
// Direct call to API function callback.
// void f(v8::FunctionCallbackInfo&)
DIRECT_API_CALL,
// Call to function callback via InvokeFunctionCallback.
// void f(v8::FunctionCallbackInfo&, v8::FunctionCallback)
PROFILING_API_CALL,
// Direct call to accessor getter callback.
// void f(Local<Name> property, PropertyCallbackInfo& info)
DIRECT_GETTER_CALL,
// Call to accessor getter callback via InvokeAccessorGetterCallback.
// void f(Local<Name> property, PropertyCallbackInfo& info,
// AccessorNameGetterCallback callback)
PROFILING_GETTER_CALL
};
static void SetUp();
static void InitializeMathExpData();
static void TearDownMathExpData();
typedef void* ExternalReferenceRedirector(void* original, Type type);
ExternalReference() : address_(NULL) {}
ExternalReference(Builtins::CFunctionId id, Isolate* isolate);
ExternalReference(ApiFunction* ptr, Type type, Isolate* isolate);
ExternalReference(Builtins::Name name, Isolate* isolate);
ExternalReference(Runtime::FunctionId id, Isolate* isolate);
ExternalReference(const Runtime::Function* f, Isolate* isolate);
ExternalReference(const IC_Utility& ic_utility, Isolate* isolate);
explicit ExternalReference(StatsCounter* counter);
ExternalReference(Isolate::AddressId id, Isolate* isolate);
explicit ExternalReference(const SCTableReference& table_ref);
// Isolate as an external reference.
static ExternalReference isolate_address(Isolate* isolate);
// One-of-a-kind references. These references are not part of a general
// pattern. This means that they have to be added to the
// ExternalReferenceTable in serialize.cc manually.
static ExternalReference incremental_marking_record_write_function(
Isolate* isolate);
static ExternalReference store_buffer_overflow_function(
Isolate* isolate);
static ExternalReference flush_icache_function(Isolate* isolate);
static ExternalReference delete_handle_scope_extensions(Isolate* isolate);
static ExternalReference get_date_field_function(Isolate* isolate);
static ExternalReference date_cache_stamp(Isolate* isolate);
static ExternalReference get_make_code_young_function(Isolate* isolate);
static ExternalReference get_mark_code_as_executed_function(Isolate* isolate);
// Deoptimization support.
static ExternalReference new_deoptimizer_function(Isolate* isolate);
static ExternalReference compute_output_frames_function(Isolate* isolate);
// Log support.
static ExternalReference log_enter_external_function(Isolate* isolate);
static ExternalReference log_leave_external_function(Isolate* isolate);
// Static data in the keyed lookup cache.
static ExternalReference keyed_lookup_cache_keys(Isolate* isolate);
static ExternalReference keyed_lookup_cache_field_offsets(Isolate* isolate);
// Static variable Heap::roots_array_start()
static ExternalReference roots_array_start(Isolate* isolate);
// Static variable Heap::allocation_sites_list_address()
static ExternalReference allocation_sites_list_address(Isolate* isolate);
// Static variable StackGuard::address_of_jslimit()
static ExternalReference address_of_stack_limit(Isolate* isolate);
// Static variable StackGuard::address_of_real_jslimit()
static ExternalReference address_of_real_stack_limit(Isolate* isolate);
// Static variable RegExpStack::limit_address()
static ExternalReference address_of_regexp_stack_limit(Isolate* isolate);
// Static variables for RegExp.
static ExternalReference address_of_static_offsets_vector(Isolate* isolate);
static ExternalReference address_of_regexp_stack_memory_address(
Isolate* isolate);
static ExternalReference address_of_regexp_stack_memory_size(
Isolate* isolate);
// Static variable Heap::NewSpaceStart()
static ExternalReference new_space_start(Isolate* isolate);
static ExternalReference new_space_mask(Isolate* isolate);
// Write barrier.
static ExternalReference store_buffer_top(Isolate* isolate);
// Used for fast allocation in generated code.
static ExternalReference new_space_allocation_top_address(Isolate* isolate);
static ExternalReference new_space_allocation_limit_address(Isolate* isolate);
static ExternalReference old_pointer_space_allocation_top_address(
Isolate* isolate);
static ExternalReference old_pointer_space_allocation_limit_address(
Isolate* isolate);
static ExternalReference old_data_space_allocation_top_address(
Isolate* isolate);
static ExternalReference old_data_space_allocation_limit_address(
Isolate* isolate);
static ExternalReference mod_two_doubles_operation(Isolate* isolate);
static ExternalReference power_double_double_function(Isolate* isolate);
static ExternalReference power_double_int_function(Isolate* isolate);
static ExternalReference handle_scope_next_address(Isolate* isolate);
static ExternalReference handle_scope_limit_address(Isolate* isolate);
static ExternalReference handle_scope_level_address(Isolate* isolate);
static ExternalReference scheduled_exception_address(Isolate* isolate);
static ExternalReference address_of_pending_message_obj(Isolate* isolate);
static ExternalReference address_of_has_pending_message(Isolate* isolate);
static ExternalReference address_of_pending_message_script(Isolate* isolate);
// Static variables containing common double constants.
static ExternalReference address_of_min_int();
static ExternalReference address_of_one_half();
static ExternalReference address_of_minus_one_half();
static ExternalReference address_of_negative_infinity();
static ExternalReference address_of_canonical_non_hole_nan();
static ExternalReference address_of_the_hole_nan();
static ExternalReference address_of_uint32_bias();
static ExternalReference math_log_double_function(Isolate* isolate);
static ExternalReference math_exp_constants(int constant_index);
static ExternalReference math_exp_log_table();
static ExternalReference page_flags(Page* page);
static ExternalReference ForDeoptEntry(Address entry);
static ExternalReference cpu_features();
static ExternalReference debug_is_active_address(Isolate* isolate);
static ExternalReference debug_after_break_target_address(Isolate* isolate);
static ExternalReference debug_restarter_frame_function_pointer_address(
Isolate* isolate);
static ExternalReference is_profiling_address(Isolate* isolate);
static ExternalReference invoke_function_callback(Isolate* isolate);
static ExternalReference invoke_accessor_getter_callback(Isolate* isolate);
Address address() const { return reinterpret_cast<Address>(address_); }
// Function Debug::Break()
static ExternalReference debug_break(Isolate* isolate);
// Used to check if single stepping is enabled in generated code.
static ExternalReference debug_step_in_fp_address(Isolate* isolate);
#ifndef V8_INTERPRETED_REGEXP
// C functions called from RegExp generated code.
// Function NativeRegExpMacroAssembler::CaseInsensitiveCompareUC16()
static ExternalReference re_case_insensitive_compare_uc16(Isolate* isolate);
// Function RegExpMacroAssembler*::CheckStackGuardState()
static ExternalReference re_check_stack_guard_state(Isolate* isolate);
// Function NativeRegExpMacroAssembler::GrowStack()
static ExternalReference re_grow_stack(Isolate* isolate);
// byte NativeRegExpMacroAssembler::word_character_bitmap
static ExternalReference re_word_character_map();
#endif
// This lets you register a function that rewrites all external references.
// Used by the ARM simulator to catch calls to external references.
static void set_redirector(Isolate* isolate,
ExternalReferenceRedirector* redirector) {
// We can't stack them.
DCHECK(isolate->external_reference_redirector() == NULL);
isolate->set_external_reference_redirector(
reinterpret_cast<ExternalReferenceRedirectorPointer*>(redirector));
}
static ExternalReference stress_deopt_count(Isolate* isolate);
bool operator==(const ExternalReference& other) const {
return address_ == other.address_;
}
bool operator!=(const ExternalReference& other) const {
return !(*this == other);
}
private:
explicit ExternalReference(void* address)
: address_(address) {}
static void* Redirect(Isolate* isolate,
Address address_arg,
Type type = ExternalReference::BUILTIN_CALL) {
ExternalReferenceRedirector* redirector =
reinterpret_cast<ExternalReferenceRedirector*>(
isolate->external_reference_redirector());
void* address = reinterpret_cast<void*>(address_arg);
void* answer = (redirector == NULL) ?
address :
(*redirector)(address, type);
return answer;
}
void* address_;
};
// -----------------------------------------------------------------------------
// Position recording support
struct PositionState {
PositionState() : current_position(RelocInfo::kNoPosition),
written_position(RelocInfo::kNoPosition),
current_statement_position(RelocInfo::kNoPosition),
written_statement_position(RelocInfo::kNoPosition) {}
int current_position;
int written_position;
int current_statement_position;
int written_statement_position;
};
class PositionsRecorder BASE_EMBEDDED {
public:
explicit PositionsRecorder(Assembler* assembler)
: assembler_(assembler) {
jit_handler_data_ = NULL;
}
void AttachJITHandlerData(void* user_data) {
jit_handler_data_ = user_data;
}
void* DetachJITHandlerData() {
void* old_data = jit_handler_data_;
jit_handler_data_ = NULL;
return old_data;
}
// Set current position to pos.
void RecordPosition(int pos);
// Set current statement position to pos.
void RecordStatementPosition(int pos);
// Write recorded positions to relocation information.
bool WriteRecordedPositions();
int current_position() const { return state_.current_position; }
int current_statement_position() const {
return state_.current_statement_position;
}
private:
Assembler* assembler_;
PositionState state_;
// Currently jit_handler_data_ is used to store JITHandler-specific data
// over the lifetime of a PositionsRecorder
void* jit_handler_data_;
friend class PreservePositionScope;
DISALLOW_COPY_AND_ASSIGN(PositionsRecorder);
};
class PreservePositionScope BASE_EMBEDDED {
public:
explicit PreservePositionScope(PositionsRecorder* positions_recorder)
: positions_recorder_(positions_recorder),
saved_state_(positions_recorder->state_) {}
~PreservePositionScope() {
positions_recorder_->state_ = saved_state_;
}
private:
PositionsRecorder* positions_recorder_;
const PositionState saved_state_;
DISALLOW_COPY_AND_ASSIGN(PreservePositionScope);
};
// -----------------------------------------------------------------------------
// Utility functions
inline int NumberOfBitsSet(uint32_t x) {
unsigned int num_bits_set;
for (num_bits_set = 0; x; x >>= 1) {
num_bits_set += x & 1;
}
return num_bits_set;
}
bool EvalComparison(Token::Value op, double op1, double op2);
// Computes pow(x, y) with the special cases in the spec for Math.pow.
double power_helper(double x, double y);
double power_double_int(double x, int y);
double power_double_double(double x, double y);
// Helper class for generating code or data associated with the code
// right after a call instruction. As an example this can be used to
// generate safepoint data after calls for crankshaft.
class CallWrapper {
public:
CallWrapper() { }
virtual ~CallWrapper() { }
// Called just before emitting a call. Argument is the size of the generated
// call code.
virtual void BeforeCall(int call_size) const = 0;
// Called just after emitting a call, i.e., at the return site for the call.
virtual void AfterCall() const = 0;
};
class NullCallWrapper : public CallWrapper {
public:
NullCallWrapper() { }
virtual ~NullCallWrapper() { }
virtual void BeforeCall(int call_size) const { }
virtual void AfterCall() const { }
};
} } // namespace v8::internal
#endif // V8_ASSEMBLER_H_