1 // Copyright (c) 1994-2006 Sun Microsystems Inc.
2 // All Rights Reserved.
4 // Redistribution and use in source and binary forms, with or without
5 // modification, are permitted provided that the following conditions are
8 // - Redistributions of source code must retain the above copyright notice,
9 // this list of conditions and the following disclaimer.
11 // - Redistribution in binary form must reproduce the above copyright
12 // notice, this list of conditions and the following disclaimer in the
13 // documentation and/or other materials provided with the distribution.
15 // - Neither the name of Sun Microsystems or the names of contributors may
16 // be used to endorse or promote products derived from this software without
17 // specific prior written permission.
19 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
20 // IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
21 // THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 // PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
23 // CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
24 // EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
25 // PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
26 // PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
27 // LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
28 // NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
29 // SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31 // The original source code covered by the above license above has been
32 // modified significantly by Google Inc.
33 // Copyright 2012 the V8 project authors. All rights reserved.
35 #ifndef V8_ASSEMBLER_H_
36 #define V8_ASSEMBLER_H_
40 #include "src/allocation.h"
41 #include "src/builtins.h"
42 #include "src/gdb-jit.h"
43 #include "src/isolate.h"
44 #include "src/runtime/runtime.h"
45 #include "src/token.h"
54 // -----------------------------------------------------------------------------
55 // Platform independent assembler base class.
57 class AssemblerBase: public Malloced {
59 AssemblerBase(Isolate* isolate, void* buffer, int buffer_size);
60 virtual ~AssemblerBase();
62 Isolate* isolate() const { return isolate_; }
63 int jit_cookie() const { return jit_cookie_; }
65 bool emit_debug_code() const { return emit_debug_code_; }
66 void set_emit_debug_code(bool value) { emit_debug_code_ = value; }
68 bool serializer_enabled() const { return serializer_enabled_; }
69 void enable_serializer() { serializer_enabled_ = true; }
71 bool predictable_code_size() const { return predictable_code_size_; }
72 void set_predictable_code_size(bool value) { predictable_code_size_ = value; }
74 uint64_t enabled_cpu_features() const { return enabled_cpu_features_; }
75 void set_enabled_cpu_features(uint64_t features) {
76 enabled_cpu_features_ = features;
78 bool IsEnabled(CpuFeature f) {
79 return (enabled_cpu_features_ & (static_cast<uint64_t>(1) << f)) != 0;
82 bool is_ool_constant_pool_available() const {
83 if (FLAG_enable_ool_constant_pool) {
84 return ool_constant_pool_available_;
86 // Out-of-line constant pool not supported on this architecture.
92 // Overwrite a host NaN with a quiet target NaN. Used by mksnapshot for
93 // cross-snapshotting.
94 static void QuietNaN(HeapObject* nan) { }
96 int pc_offset() const { return static_cast<int>(pc_ - buffer_); }
98 // This function is called when code generation is aborted, so that
99 // the assembler could clean up internal data structures.
100 virtual void AbortedCodeGeneration() { }
102 static const int kMinimalBufferSize = 4*KB;
105 // The buffer into which code and relocation info are generated. It could
106 // either be owned by the assembler or be provided externally.
111 void set_ool_constant_pool_available(bool available) {
112 if (FLAG_enable_ool_constant_pool) {
113 ool_constant_pool_available_ = available;
115 // Out-of-line constant pool not supported on this architecture.
120 // The program counter, which points into the buffer above and moves forward.
126 uint64_t enabled_cpu_features_;
127 bool emit_debug_code_;
128 bool predictable_code_size_;
129 bool serializer_enabled_;
131 // Indicates whether the constant pool can be accessed, which is only possible
132 // if the pp register points to the current code object's constant pool.
133 bool ool_constant_pool_available_;
136 friend class FrameAndConstantPoolScope;
137 friend class ConstantPoolUnavailableScope;
141 // Avoids emitting debug code during the lifetime of this scope object.
142 class DontEmitDebugCodeScope BASE_EMBEDDED {
144 explicit DontEmitDebugCodeScope(AssemblerBase* assembler)
145 : assembler_(assembler), old_value_(assembler->emit_debug_code()) {
146 assembler_->set_emit_debug_code(false);
148 ~DontEmitDebugCodeScope() {
149 assembler_->set_emit_debug_code(old_value_);
152 AssemblerBase* assembler_;
157 // Avoids using instructions that vary in size in unpredictable ways between the
158 // snapshot and the running VM.
159 class PredictableCodeSizeScope {
161 PredictableCodeSizeScope(AssemblerBase* assembler, int expected_size);
162 ~PredictableCodeSizeScope();
165 AssemblerBase* assembler_;
172 // Enable a specified feature within a scope.
173 class CpuFeatureScope BASE_EMBEDDED {
176 CpuFeatureScope(AssemblerBase* assembler, CpuFeature f);
180 AssemblerBase* assembler_;
181 uint64_t old_enabled_;
183 CpuFeatureScope(AssemblerBase* assembler, CpuFeature f) {}
188 // CpuFeatures keeps track of which features are supported by the target CPU.
189 // Supported features must be enabled by a CpuFeatureScope before use.
191 // if (assembler->IsSupported(SSE3)) {
192 // CpuFeatureScope fscope(assembler, SSE3);
193 // // Generate code containing SSE3 instructions.
195 // // Generate alternative code.
197 class CpuFeatures : public AllStatic {
199 static void Probe(bool cross_compile) {
200 STATIC_ASSERT(NUMBER_OF_CPU_FEATURES <= kBitsPerInt);
201 if (initialized_) return;
203 ProbeImpl(cross_compile);
206 static unsigned SupportedFeatures() {
211 static bool IsSupported(CpuFeature f) {
212 return (supported_ & (1u << f)) != 0;
215 static inline bool SupportsCrankshaft();
217 static inline unsigned cache_line_size() {
218 DCHECK(cache_line_size_ != 0);
219 return cache_line_size_;
222 static void PrintTarget();
223 static void PrintFeatures();
225 // Flush instruction cache.
226 static void FlushICache(void* start, size_t size);
229 // Platform-dependent implementation.
230 static void ProbeImpl(bool cross_compile);
232 static unsigned supported_;
233 static unsigned cache_line_size_;
234 static bool initialized_;
235 friend class ExternalReference;
236 DISALLOW_COPY_AND_ASSIGN(CpuFeatures);
240 // -----------------------------------------------------------------------------
241 // Labels represent pc locations; they are typically jump or call targets.
242 // After declaration, a label can be freely used to denote known or (yet)
243 // unknown pc location. Assembler::bind() is used to bind a label to the
244 // current pc. A label can be bound only once.
258 DCHECK(!is_linked());
259 DCHECK(!is_near_linked());
262 INLINE(void Unuse()) { pos_ = 0; }
263 INLINE(void UnuseNear()) { near_link_pos_ = 0; }
265 INLINE(bool is_bound() const) { return pos_ < 0; }
266 INLINE(bool is_unused() const) { return pos_ == 0 && near_link_pos_ == 0; }
267 INLINE(bool is_linked() const) { return pos_ > 0; }
268 INLINE(bool is_near_linked() const) { return near_link_pos_ > 0; }
270 // Returns the position of bound or linked labels. Cannot be used
271 // for unused labels.
273 int near_link_pos() const { return near_link_pos_ - 1; }
276 // pos_ encodes both the binding state (via its sign)
277 // and the binding position (via its value) of a label.
279 // pos_ < 0 bound label, pos() returns the jump target position
280 // pos_ == 0 unused label
281 // pos_ > 0 linked label, pos() returns the last reference position
284 // Behaves like |pos_| in the "> 0" case, but for near jumps to this label.
287 void bind_to(int pos) {
291 void link_to(int pos, Distance distance = kFar) {
292 if (distance == kNear) {
293 near_link_pos_ = pos + 1;
294 DCHECK(is_near_linked());
301 friend class Assembler;
302 friend class Displacement;
303 friend class RegExpMacroAssemblerIrregexp;
305 #if V8_TARGET_ARCH_ARM64
306 // On ARM64, the Assembler keeps track of pointers to Labels to resolve
307 // branches to distant targets. Copying labels would confuse the Assembler.
308 DISALLOW_COPY_AND_ASSIGN(Label); // NOLINT
313 enum SaveFPRegsMode { kDontSaveFPRegs, kSaveFPRegs };
315 // Specifies whether to perform icache flush operations on RelocInfo updates.
316 // If FLUSH_ICACHE_IF_NEEDED, the icache will always be flushed if an
317 // instruction was modified. If SKIP_ICACHE_FLUSH the flush will always be
318 // skipped (only use this if you will flush the icache manually before it is
320 enum ICacheFlushMode { FLUSH_ICACHE_IF_NEEDED, SKIP_ICACHE_FLUSH };
322 // -----------------------------------------------------------------------------
323 // Relocation information
326 // Relocation information consists of the address (pc) of the datum
327 // to which the relocation information applies, the relocation mode
328 // (rmode), and an optional data field. The relocation mode may be
329 // "descriptive" and not indicate a need for relocation, but simply
330 // describe a property of the datum. Such rmodes are useful for GC
331 // and nice disassembly output.
335 // The constant kNoPosition is used with the collecting of source positions
336 // in the relocation information. Two types of source positions are collected
337 // "position" (RelocMode position) and "statement position" (RelocMode
338 // statement_position). The "position" is collected at places in the source
339 // code which are of interest when making stack traces to pin-point the source
340 // location of a stack frame as close as possible. The "statement position" is
341 // collected at the beginning at each statement, and is used to indicate
342 // possible break locations. kNoPosition is used to indicate an
343 // invalid/uninitialized position value.
344 static const int kNoPosition = -1;
346 // This string is used to add padding comments to the reloc info in cases
347 // where we are not sure to have enough space for patching in during
348 // lazy deoptimization. This is the case if we have indirect calls for which
349 // we do not normally record relocation info.
350 static const char* const kFillerCommentString;
352 // The minimum size of a comment is equal to three bytes for the extra tagged
353 // pc + the tag for the data, and kPointerSize for the actual pointer to the
355 static const int kMinRelocCommentSize = 3 + kPointerSize;
357 // The maximum size for a call instruction including pc-jump.
358 static const int kMaxCallSize = 6;
360 // The maximum pc delta that will use the short encoding.
361 static const int kMaxSmallPCDelta;
364 // Please note the order is important (see IsCodeTarget, IsGCRelocMode).
365 CODE_TARGET, // Code target which is not any of the above.
367 CONSTRUCT_CALL, // code target that is a call to a JavaScript constructor.
368 DEBUG_BREAK, // Code target for the debugger statement.
372 // Everything after runtime_entry (inclusive) is not GC'ed.
374 JS_RETURN, // Marks start of the ExitJSFrame code.
376 POSITION, // See comment for kNoPosition above.
377 STATEMENT_POSITION, // See comment for kNoPosition above.
378 DEBUG_BREAK_SLOT, // Additional code inserted for debug break slot.
379 EXTERNAL_REFERENCE, // The address of an external C++ function.
380 INTERNAL_REFERENCE, // An address inside the same function.
382 // Marks constant and veneer pools. Only used on ARM and ARM64.
383 // They use a custom noncompact encoding.
387 DEOPT_REASON, // Deoptimization reason index.
389 // add more as needed
391 NUMBER_OF_MODES, // There are at most 15 modes with noncompact encoding.
392 NONE32, // never recorded 32-bit value
393 NONE64, // never recorded 64-bit value
394 CODE_AGE_SEQUENCE, // Not stored in RelocInfo array, used explictly by
397 // Encoded internal reference, used only on MIPS and MIPS64.
398 // Re-uses previous ARM-only encoding, to fit in RealRelocMode space.
399 INTERNAL_REFERENCE_ENCODED = CONST_POOL,
401 FIRST_REAL_RELOC_MODE = CODE_TARGET,
402 LAST_REAL_RELOC_MODE = VENEER_POOL,
403 FIRST_PSEUDO_RELOC_MODE = CODE_AGE_SEQUENCE,
404 LAST_PSEUDO_RELOC_MODE = CODE_AGE_SEQUENCE,
405 LAST_CODE_ENUM = DEBUG_BREAK,
406 LAST_GCED_ENUM = CELL,
407 // Modes <= LAST_COMPACT_ENUM are guaranteed to have compact encoding.
408 LAST_COMPACT_ENUM = CODE_TARGET_WITH_ID,
409 LAST_STANDARD_NONCOMPACT_ENUM = INTERNAL_REFERENCE
414 RelocInfo(byte* pc, Mode rmode, intptr_t data, Code* host)
415 : pc_(pc), rmode_(rmode), data_(data), host_(host) {
417 RelocInfo(byte* pc, double data64)
418 : pc_(pc), rmode_(NONE64), data64_(data64), host_(NULL) {
421 static inline bool IsRealRelocMode(Mode mode) {
422 return mode >= FIRST_REAL_RELOC_MODE &&
423 mode <= LAST_REAL_RELOC_MODE;
425 static inline bool IsPseudoRelocMode(Mode mode) {
426 DCHECK(!IsRealRelocMode(mode));
427 return mode >= FIRST_PSEUDO_RELOC_MODE &&
428 mode <= LAST_PSEUDO_RELOC_MODE;
430 static inline bool IsConstructCall(Mode mode) {
431 return mode == CONSTRUCT_CALL;
433 static inline bool IsCodeTarget(Mode mode) {
434 return mode <= LAST_CODE_ENUM;
436 static inline bool IsEmbeddedObject(Mode mode) {
437 return mode == EMBEDDED_OBJECT;
439 static inline bool IsRuntimeEntry(Mode mode) {
440 return mode == RUNTIME_ENTRY;
442 // Is the relocation mode affected by GC?
443 static inline bool IsGCRelocMode(Mode mode) {
444 return mode <= LAST_GCED_ENUM;
446 static inline bool IsJSReturn(Mode mode) {
447 return mode == JS_RETURN;
449 static inline bool IsComment(Mode mode) {
450 return mode == COMMENT;
452 static inline bool IsConstPool(Mode mode) {
453 return mode == CONST_POOL;
455 static inline bool IsVeneerPool(Mode mode) {
456 return mode == VENEER_POOL;
458 static inline bool IsDeoptReason(Mode mode) {
459 return mode == DEOPT_REASON;
461 static inline bool IsPosition(Mode mode) {
462 return mode == POSITION || mode == STATEMENT_POSITION;
464 static inline bool IsStatementPosition(Mode mode) {
465 return mode == STATEMENT_POSITION;
467 static inline bool IsExternalReference(Mode mode) {
468 return mode == EXTERNAL_REFERENCE;
470 static inline bool IsInternalReference(Mode mode) {
471 return mode == INTERNAL_REFERENCE;
473 static inline bool IsInternalReferenceEncoded(Mode mode) {
474 return mode == INTERNAL_REFERENCE_ENCODED;
476 static inline bool IsDebugBreakSlot(Mode mode) {
477 return mode == DEBUG_BREAK_SLOT;
479 static inline bool IsNone(Mode mode) {
480 return mode == NONE32 || mode == NONE64;
482 static inline bool IsCodeAgeSequence(Mode mode) {
483 return mode == CODE_AGE_SEQUENCE;
485 static inline int ModeMask(Mode mode) { return 1 << mode; }
487 // Returns true if the first RelocInfo has the same mode and raw data as the
489 static inline bool IsEqual(RelocInfo first, RelocInfo second) {
490 return first.rmode() == second.rmode() &&
491 (first.rmode() == RelocInfo::NONE64 ?
492 first.raw_data64() == second.raw_data64() :
493 first.data() == second.data());
497 byte* pc() const { return pc_; }
498 void set_pc(byte* pc) { pc_ = pc; }
499 Mode rmode() const { return rmode_; }
500 intptr_t data() const { return data_; }
501 double data64() const { return data64_; }
502 uint64_t raw_data64() { return bit_cast<uint64_t>(data64_); }
503 Code* host() const { return host_; }
504 void set_host(Code* host) { host_ = host; }
506 // Apply a relocation by delta bytes
507 INLINE(void apply(intptr_t delta,
508 ICacheFlushMode icache_flush_mode =
509 FLUSH_ICACHE_IF_NEEDED));
511 // Is the pointer this relocation info refers to coded like a plain pointer
512 // or is it strange in some way (e.g. relative or patched into a series of
514 bool IsCodedSpecially();
516 // If true, the pointer this relocation info refers to is an entry in the
517 // constant pool, otherwise the pointer is embedded in the instruction stream.
518 bool IsInConstantPool();
520 // Read/modify the code target in the branch/call instruction
521 // this relocation applies to;
522 // can only be called if IsCodeTarget(rmode_) || IsRuntimeEntry(rmode_)
523 INLINE(Address target_address());
524 INLINE(void set_target_address(Address target,
525 WriteBarrierMode write_barrier_mode =
526 UPDATE_WRITE_BARRIER,
527 ICacheFlushMode icache_flush_mode =
528 FLUSH_ICACHE_IF_NEEDED));
529 INLINE(Object* target_object());
530 INLINE(Handle<Object> target_object_handle(Assembler* origin));
531 INLINE(void set_target_object(Object* target,
532 WriteBarrierMode write_barrier_mode =
533 UPDATE_WRITE_BARRIER,
534 ICacheFlushMode icache_flush_mode =
535 FLUSH_ICACHE_IF_NEEDED));
536 INLINE(Address target_runtime_entry(Assembler* origin));
537 INLINE(void set_target_runtime_entry(Address target,
538 WriteBarrierMode write_barrier_mode =
539 UPDATE_WRITE_BARRIER,
540 ICacheFlushMode icache_flush_mode =
541 FLUSH_ICACHE_IF_NEEDED));
542 INLINE(Cell* target_cell());
543 INLINE(Handle<Cell> target_cell_handle());
544 INLINE(void set_target_cell(Cell* cell,
545 WriteBarrierMode write_barrier_mode =
546 UPDATE_WRITE_BARRIER,
547 ICacheFlushMode icache_flush_mode =
548 FLUSH_ICACHE_IF_NEEDED));
549 INLINE(Handle<Object> code_age_stub_handle(Assembler* origin));
550 INLINE(Code* code_age_stub());
551 INLINE(void set_code_age_stub(Code* stub,
552 ICacheFlushMode icache_flush_mode =
553 FLUSH_ICACHE_IF_NEEDED));
555 // Returns the address of the constant pool entry where the target address
556 // is held. This should only be called if IsInConstantPool returns true.
557 INLINE(Address constant_pool_entry_address());
559 // Read the address of the word containing the target_address in an
560 // instruction stream. What this means exactly is architecture-independent.
561 // The only architecture-independent user of this function is the serializer.
562 // The serializer uses it to find out how many raw bytes of instruction to
563 // output before the next target. Architecture-independent code shouldn't
564 // dereference the pointer it gets back from this.
565 INLINE(Address target_address_address());
567 // This indicates how much space a target takes up when deserializing a code
568 // stream. For most architectures this is just the size of a pointer. For
569 // an instruction like movw/movt where the target bits are mixed into the
570 // instruction bits the size of the target will be zero, indicating that the
571 // serializer should not step forwards in memory after a target is resolved
572 // and written. In this case the target_address_address function above
573 // should return the end of the instructions to be patched, allowing the
574 // deserializer to deserialize the instructions as raw bytes and put them in
575 // place, ready to be patched with the target.
576 INLINE(int target_address_size());
578 // Read/modify the reference in the instruction this relocation
579 // applies to; can only be called if rmode_ is external_reference
580 INLINE(Address target_reference());
582 // Read/modify the address of a call instruction. This is used to relocate
583 // the break points where straight-line code is patched with a call
585 INLINE(Address call_address());
586 INLINE(void set_call_address(Address target));
587 INLINE(Object* call_object());
588 INLINE(void set_call_object(Object* target));
589 INLINE(Object** call_object_address());
591 // Wipe out a relocation to a fixed value, used for making snapshots
593 INLINE(void WipeOut());
595 template<typename StaticVisitor> inline void Visit(Heap* heap);
596 inline void Visit(Isolate* isolate, ObjectVisitor* v);
598 // Patch the code with some other code.
599 void PatchCode(byte* instructions, int instruction_count);
601 // Patch the code with a call.
602 void PatchCodeWithCall(Address target, int guard_bytes);
604 // Check whether this return sequence has been patched
605 // with a call to the debugger.
606 INLINE(bool IsPatchedReturnSequence());
608 // Check whether this debug break slot has been patched with a call to the
610 INLINE(bool IsPatchedDebugBreakSlotSequence());
613 // Check whether the given code contains relocation information that
614 // either is position-relative or movable by the garbage collector.
615 static bool RequiresRelocation(const CodeDesc& desc);
618 #ifdef ENABLE_DISASSEMBLER
620 static const char* RelocModeName(Mode rmode);
621 void Print(Isolate* isolate, std::ostream& os); // NOLINT
622 #endif // ENABLE_DISASSEMBLER
624 void Verify(Isolate* isolate);
627 static const int kCodeTargetMask = (1 << (LAST_CODE_ENUM + 1)) - 1;
628 static const int kPositionMask = 1 << POSITION | 1 << STATEMENT_POSITION;
629 static const int kDataMask =
630 (1 << CODE_TARGET_WITH_ID) | kPositionMask | (1 << COMMENT);
631 static const int kApplyMask; // Modes affected by apply. Depends on arch.
634 // On ARM, note that pc_ is the address of the constant pool entry
635 // to be relocated and not the address of the instruction
636 // referencing the constant pool entry (except when rmode_ ==
645 // External-reference pointers are also split across instruction-pairs
646 // on some platforms, but are accessed via indirect pointers. This location
647 // provides a place for that pointer to exist naturally. Its address
648 // is returned by RelocInfo::target_reference_address().
649 Address reconstructed_adr_ptr_;
650 friend class RelocIterator;
654 // RelocInfoWriter serializes a stream of relocation info. It writes towards
656 class RelocInfoWriter BASE_EMBEDDED {
663 last_mode_(RelocInfo::NUMBER_OF_MODES),
664 next_position_candidate_pos_delta_(0),
665 next_position_candidate_pc_delta_(0),
666 next_position_candidate_flushed_(true) {}
667 RelocInfoWriter(byte* pos, byte* pc)
672 last_mode_(RelocInfo::NUMBER_OF_MODES),
673 next_position_candidate_pos_delta_(0),
674 next_position_candidate_pc_delta_(0),
675 next_position_candidate_flushed_(true) {}
677 byte* pos() const { return pos_; }
678 byte* last_pc() const { return last_pc_; }
680 void Write(const RelocInfo* rinfo);
682 // Update the state of the stream after reloc info buffer
683 // and/or code is moved while the stream is active.
684 void Reposition(byte* pos, byte* pc) {
689 void Finish() { FlushPosition(); }
691 // Max size (bytes) of a written RelocInfo. Longest encoding is
692 // ExtraTag, VariableLengthPCJump, ExtraTag, pc_delta, ExtraTag, data_delta.
693 // On ia32 and arm this is 1 + 4 + 1 + 1 + 1 + 4 = 12.
694 // On x64 this is 1 + 4 + 1 + 1 + 1 + 8 == 16;
695 // Here we use the maximum of the two.
696 static const int kMaxSize = 16;
699 inline uint32_t WriteVariableLengthPCJump(uint32_t pc_delta);
700 inline void WriteTaggedPC(uint32_t pc_delta, int tag);
701 inline void WriteExtraTaggedPC(uint32_t pc_delta, int extra_tag);
702 inline void WriteExtraTaggedIntData(int data_delta, int top_tag);
703 inline void WriteExtraTaggedPoolData(int data, int pool_type);
704 inline void WriteExtraTaggedData(intptr_t data_delta, int top_tag);
705 inline void WriteTaggedData(intptr_t data_delta, int tag);
706 inline void WriteExtraTag(int extra_tag, int top_tag);
707 inline void WritePosition(int pc_delta, int pos_delta, RelocInfo::Mode rmode);
709 void FlushPosition();
715 RelocInfo::Mode last_mode_;
716 int next_position_candidate_pos_delta_;
717 uint32_t next_position_candidate_pc_delta_;
718 bool next_position_candidate_flushed_;
720 DISALLOW_COPY_AND_ASSIGN(RelocInfoWriter);
724 // A RelocIterator iterates over relocation information.
727 // for (RelocIterator it(code); !it.done(); it.next()) {
728 // // do something with it.rinfo() here
731 // A mask can be specified to skip unwanted modes.
732 class RelocIterator: public Malloced {
734 // Create a new iterator positioned at
735 // the beginning of the reloc info.
736 // Relocation information with mode k is included in the
737 // iteration iff bit k of mode_mask is set.
738 explicit RelocIterator(Code* code, int mode_mask = -1);
739 explicit RelocIterator(const CodeDesc& desc, int mode_mask = -1);
742 bool done() const { return done_; }
745 // Return pointer valid until next next().
752 // Advance* moves the position before/after reading.
753 // *Read* reads from current byte(s) into rinfo_.
754 // *Get* just reads and returns info on current byte.
755 void Advance(int bytes = 1) { pos_ -= bytes; }
760 void AdvanceReadPC();
761 void AdvanceReadId();
762 void AdvanceReadPoolData();
763 void AdvanceReadPosition();
764 void AdvanceReadData();
765 void AdvanceReadVariableLengthPCJump();
766 int GetLocatableTypeTag();
768 void ReadTaggedPosition();
769 void ReadTaggedData();
771 // If the given mode is wanted, set it in rinfo_ and return true.
772 // Else return false. Used for efficiently skipping unwanted modes.
773 bool SetMode(RelocInfo::Mode mode) {
774 return (mode_mask_ & (1 << mode)) ? (rinfo_.rmode_ = mode, true) : false;
779 byte* code_age_sequence_;
785 DISALLOW_COPY_AND_ASSIGN(RelocIterator);
789 //------------------------------------------------------------------------------
792 //----------------------------------------------------------------------------
794 class SCTableReference;
798 // An ExternalReference represents a C++ address used in the generated
799 // code. All references to C++ functions and variables must be encapsulated in
800 // an ExternalReference instance. This is done in order to track the origin of
801 // all external references in the code so that they can be bound to the correct
802 // addresses when deserializing a heap.
803 class ExternalReference BASE_EMBEDDED {
805 // Used in the simulator to support different native api calls.
808 // Object* f(v8::internal::Arguments).
809 BUILTIN_CALL, // default
811 // Builtin that takes float arguments and returns an int.
812 // int f(double, double).
813 BUILTIN_COMPARE_CALL,
815 // Builtin call that returns floating point.
816 // double f(double, double).
819 // Builtin call that returns floating point.
823 // Builtin call that returns floating point.
824 // double f(double, int).
827 // Direct call to API function callback.
828 // void f(v8::FunctionCallbackInfo&)
831 // Call to function callback via InvokeFunctionCallback.
832 // void f(v8::FunctionCallbackInfo&, v8::FunctionCallback)
835 // Direct call to accessor getter callback.
836 // void f(Local<Name> property, PropertyCallbackInfo& info)
839 // Call to accessor getter callback via InvokeAccessorGetterCallback.
840 // void f(Local<Name> property, PropertyCallbackInfo& info,
841 // AccessorNameGetterCallback callback)
842 PROFILING_GETTER_CALL
846 static void InitializeMathExpData();
847 static void TearDownMathExpData();
849 typedef void* ExternalReferenceRedirector(void* original, Type type);
851 ExternalReference() : address_(NULL) {}
853 ExternalReference(Builtins::CFunctionId id, Isolate* isolate);
855 ExternalReference(ApiFunction* ptr, Type type, Isolate* isolate);
857 ExternalReference(Builtins::Name name, Isolate* isolate);
859 ExternalReference(Runtime::FunctionId id, Isolate* isolate);
861 ExternalReference(const Runtime::Function* f, Isolate* isolate);
863 ExternalReference(const IC_Utility& ic_utility, Isolate* isolate);
865 explicit ExternalReference(StatsCounter* counter);
867 ExternalReference(Isolate::AddressId id, Isolate* isolate);
869 explicit ExternalReference(const SCTableReference& table_ref);
871 // Isolate as an external reference.
872 static ExternalReference isolate_address(Isolate* isolate);
874 // One-of-a-kind references. These references are not part of a general
875 // pattern. This means that they have to be added to the
876 // ExternalReferenceTable in serialize.cc manually.
878 static ExternalReference incremental_marking_record_write_function(
880 static ExternalReference store_buffer_overflow_function(
882 static ExternalReference flush_icache_function(Isolate* isolate);
883 static ExternalReference delete_handle_scope_extensions(Isolate* isolate);
885 static ExternalReference get_date_field_function(Isolate* isolate);
886 static ExternalReference date_cache_stamp(Isolate* isolate);
888 static ExternalReference get_make_code_young_function(Isolate* isolate);
889 static ExternalReference get_mark_code_as_executed_function(Isolate* isolate);
891 // Deoptimization support.
892 static ExternalReference new_deoptimizer_function(Isolate* isolate);
893 static ExternalReference compute_output_frames_function(Isolate* isolate);
896 static ExternalReference log_enter_external_function(Isolate* isolate);
897 static ExternalReference log_leave_external_function(Isolate* isolate);
899 // Static data in the keyed lookup cache.
900 static ExternalReference keyed_lookup_cache_keys(Isolate* isolate);
901 static ExternalReference keyed_lookup_cache_field_offsets(Isolate* isolate);
903 // Static variable Heap::roots_array_start()
904 static ExternalReference roots_array_start(Isolate* isolate);
906 // Static variable Heap::allocation_sites_list_address()
907 static ExternalReference allocation_sites_list_address(Isolate* isolate);
909 // Static variable StackGuard::address_of_jslimit()
910 static ExternalReference address_of_stack_limit(Isolate* isolate);
912 // Static variable StackGuard::address_of_real_jslimit()
913 static ExternalReference address_of_real_stack_limit(Isolate* isolate);
915 // Static variable RegExpStack::limit_address()
916 static ExternalReference address_of_regexp_stack_limit(Isolate* isolate);
918 // Static variables for RegExp.
919 static ExternalReference address_of_static_offsets_vector(Isolate* isolate);
920 static ExternalReference address_of_regexp_stack_memory_address(
922 static ExternalReference address_of_regexp_stack_memory_size(
925 // Static variable Heap::NewSpaceStart()
926 static ExternalReference new_space_start(Isolate* isolate);
927 static ExternalReference new_space_mask(Isolate* isolate);
930 static ExternalReference store_buffer_top(Isolate* isolate);
932 // Used for fast allocation in generated code.
933 static ExternalReference new_space_allocation_top_address(Isolate* isolate);
934 static ExternalReference new_space_allocation_limit_address(Isolate* isolate);
935 static ExternalReference old_pointer_space_allocation_top_address(
937 static ExternalReference old_pointer_space_allocation_limit_address(
939 static ExternalReference old_data_space_allocation_top_address(
941 static ExternalReference old_data_space_allocation_limit_address(
944 static ExternalReference mod_two_doubles_operation(Isolate* isolate);
945 static ExternalReference power_double_double_function(Isolate* isolate);
946 static ExternalReference power_double_int_function(Isolate* isolate);
948 static ExternalReference handle_scope_next_address(Isolate* isolate);
949 static ExternalReference handle_scope_limit_address(Isolate* isolate);
950 static ExternalReference handle_scope_level_address(Isolate* isolate);
952 static ExternalReference scheduled_exception_address(Isolate* isolate);
953 static ExternalReference address_of_pending_message_obj(Isolate* isolate);
954 static ExternalReference address_of_has_pending_message(Isolate* isolate);
955 static ExternalReference address_of_pending_message_script(Isolate* isolate);
957 // Static variables containing common double constants.
958 static ExternalReference address_of_min_int();
959 static ExternalReference address_of_one_half();
960 static ExternalReference address_of_minus_one_half();
961 static ExternalReference address_of_negative_infinity();
962 static ExternalReference address_of_the_hole_nan();
963 static ExternalReference address_of_uint32_bias();
965 static ExternalReference math_log_double_function(Isolate* isolate);
967 static ExternalReference math_exp_constants(int constant_index);
968 static ExternalReference math_exp_log_table();
970 static ExternalReference page_flags(Page* page);
972 static ExternalReference ForDeoptEntry(Address entry);
974 static ExternalReference cpu_features();
976 static ExternalReference debug_is_active_address(Isolate* isolate);
977 static ExternalReference debug_after_break_target_address(Isolate* isolate);
978 static ExternalReference debug_restarter_frame_function_pointer_address(
981 static ExternalReference is_profiling_address(Isolate* isolate);
982 static ExternalReference invoke_function_callback(Isolate* isolate);
983 static ExternalReference invoke_accessor_getter_callback(Isolate* isolate);
985 Address address() const { return reinterpret_cast<Address>(address_); }
987 // Function Debug::Break()
988 static ExternalReference debug_break(Isolate* isolate);
990 // Used to check if single stepping is enabled in generated code.
991 static ExternalReference debug_step_in_fp_address(Isolate* isolate);
993 #ifndef V8_INTERPRETED_REGEXP
994 // C functions called from RegExp generated code.
996 // Function NativeRegExpMacroAssembler::CaseInsensitiveCompareUC16()
997 static ExternalReference re_case_insensitive_compare_uc16(Isolate* isolate);
999 // Function RegExpMacroAssembler*::CheckStackGuardState()
1000 static ExternalReference re_check_stack_guard_state(Isolate* isolate);
1002 // Function NativeRegExpMacroAssembler::GrowStack()
1003 static ExternalReference re_grow_stack(Isolate* isolate);
1005 // byte NativeRegExpMacroAssembler::word_character_bitmap
1006 static ExternalReference re_word_character_map();
1010 // This lets you register a function that rewrites all external references.
1011 // Used by the ARM simulator to catch calls to external references.
1012 static void set_redirector(Isolate* isolate,
1013 ExternalReferenceRedirector* redirector) {
1014 // We can't stack them.
1015 DCHECK(isolate->external_reference_redirector() == NULL);
1016 isolate->set_external_reference_redirector(
1017 reinterpret_cast<ExternalReferenceRedirectorPointer*>(redirector));
1020 static ExternalReference stress_deopt_count(Isolate* isolate);
1023 explicit ExternalReference(void* address)
1024 : address_(address) {}
1026 static void* Redirect(Isolate* isolate,
1027 Address address_arg,
1028 Type type = ExternalReference::BUILTIN_CALL) {
1029 ExternalReferenceRedirector* redirector =
1030 reinterpret_cast<ExternalReferenceRedirector*>(
1031 isolate->external_reference_redirector());
1032 void* address = reinterpret_cast<void*>(address_arg);
1033 void* answer = (redirector == NULL) ?
1035 (*redirector)(address, type);
1042 bool operator==(ExternalReference, ExternalReference);
1043 bool operator!=(ExternalReference, ExternalReference);
1045 size_t hash_value(ExternalReference);
1047 std::ostream& operator<<(std::ostream&, ExternalReference);
1050 // -----------------------------------------------------------------------------
1051 // Position recording support
1053 struct PositionState {
1054 PositionState() : current_position(RelocInfo::kNoPosition),
1055 written_position(RelocInfo::kNoPosition),
1056 current_statement_position(RelocInfo::kNoPosition),
1057 written_statement_position(RelocInfo::kNoPosition) {}
1059 int current_position;
1060 int written_position;
1062 int current_statement_position;
1063 int written_statement_position;
1067 class PositionsRecorder BASE_EMBEDDED {
1069 explicit PositionsRecorder(Assembler* assembler)
1070 : assembler_(assembler) {
1071 jit_handler_data_ = NULL;
1074 void AttachJITHandlerData(void* user_data) {
1075 jit_handler_data_ = user_data;
1078 void* DetachJITHandlerData() {
1079 void* old_data = jit_handler_data_;
1080 jit_handler_data_ = NULL;
1083 // Set current position to pos.
1084 void RecordPosition(int pos);
1086 // Set current statement position to pos.
1087 void RecordStatementPosition(int pos);
1089 // Write recorded positions to relocation information.
1090 bool WriteRecordedPositions();
1092 int current_position() const { return state_.current_position; }
1094 int current_statement_position() const {
1095 return state_.current_statement_position;
1099 Assembler* assembler_;
1100 PositionState state_;
1102 // Currently jit_handler_data_ is used to store JITHandler-specific data
1103 // over the lifetime of a PositionsRecorder
1104 void* jit_handler_data_;
1105 friend class PreservePositionScope;
1107 DISALLOW_COPY_AND_ASSIGN(PositionsRecorder);
1111 class PreservePositionScope BASE_EMBEDDED {
1113 explicit PreservePositionScope(PositionsRecorder* positions_recorder)
1114 : positions_recorder_(positions_recorder),
1115 saved_state_(positions_recorder->state_) {}
1117 ~PreservePositionScope() {
1118 positions_recorder_->state_ = saved_state_;
1122 PositionsRecorder* positions_recorder_;
1123 const PositionState saved_state_;
1125 DISALLOW_COPY_AND_ASSIGN(PreservePositionScope);
1129 // -----------------------------------------------------------------------------
1130 // Utility functions
1132 inline int NumberOfBitsSet(uint32_t x) {
1133 unsigned int num_bits_set;
1134 for (num_bits_set = 0; x; x >>= 1) {
1135 num_bits_set += x & 1;
1137 return num_bits_set;
1140 bool EvalComparison(Token::Value op, double op1, double op2);
1142 // Computes pow(x, y) with the special cases in the spec for Math.pow.
1143 double power_helper(double x, double y);
1144 double power_double_int(double x, int y);
1145 double power_double_double(double x, double y);
1147 // Helper class for generating code or data associated with the code
1148 // right after a call instruction. As an example this can be used to
1149 // generate safepoint data after calls for crankshaft.
1153 virtual ~CallWrapper() { }
1154 // Called just before emitting a call. Argument is the size of the generated
1156 virtual void BeforeCall(int call_size) const = 0;
1157 // Called just after emitting a call, i.e., at the return site for the call.
1158 virtual void AfterCall() const = 0;
1161 class NullCallWrapper : public CallWrapper {
1163 NullCallWrapper() { }
1164 virtual ~NullCallWrapper() { }
1165 virtual void BeforeCall(int call_size) const { }
1166 virtual void AfterCall() const { }
1170 } } // namespace v8::internal
1172 #endif // V8_ASSEMBLER_H_