| // 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 2006-2008 the V8 project authors. All rights reserved. |
| |
| #ifndef V8_ASSEMBLER_H_ |
| #define V8_ASSEMBLER_H_ |
| |
| #include "runtime.h" |
| #include "top.h" |
| #include "zone-inl.h" |
| |
| namespace v8 { namespace internal { |
| |
| |
| // ----------------------------------------------------------------------------- |
| // 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 : public ZoneObject { // LabelShadows are dynamically allocated. |
| public: |
| INLINE(Label()) { Unuse(); } |
| INLINE(~Label()) { ASSERT(!is_linked()); } |
| |
| INLINE(void Unuse()) { pos_ = 0; } |
| |
| INLINE(bool is_bound() const) { return pos_ < 0; } |
| INLINE(bool is_unused() const) { return pos_ == 0; } |
| INLINE(bool is_linked() const) { return pos_ > 0; } |
| |
| // Returns the position of bound or linked labels. Cannot be used |
| // for unused labels. |
| int pos() const; |
| |
| 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_; |
| |
| void bind_to(int pos) { |
| pos_ = -pos - 1; |
| ASSERT(is_bound()); |
| } |
| void link_to(int pos) { |
| pos_ = pos + 1; |
| ASSERT(is_linked()); |
| } |
| |
| friend class Assembler; |
| friend class RegexpAssembler; |
| friend class Displacement; |
| friend class LabelShadow; |
| friend class RegExpMacroAssemblerIrregexp; |
| }; |
| |
| |
| // A LabelShadow represents a label that is temporarily shadowed by another |
| // label (represented by the original label during shadowing). They are used |
| // to catch jumps to labels in certain contexts, e.g. try blocks. After |
| // shadowing ends, the formerly shadowed label is again represented by the |
| // original label and the LabelShadow can be used as a label in its own |
| // right, representing the formerly shadowing label. |
| class LabelShadow : public Label { |
| public: |
| explicit LabelShadow(Label* original) { |
| ASSERT(original != NULL); |
| original_label_ = original; |
| original_pos_ = original->pos_; |
| original->Unuse(); |
| #ifdef DEBUG |
| is_shadowing_ = true; |
| #endif |
| } |
| |
| ~LabelShadow() { |
| ASSERT(!is_shadowing_); |
| } |
| |
| void StopShadowing() { |
| ASSERT(is_shadowing_ && is_unused()); |
| pos_ = original_label_->pos_; |
| original_label_->pos_ = original_pos_; |
| #ifdef DEBUG |
| is_shadowing_ = false; |
| #endif |
| } |
| |
| Label* original_label() const { return original_label_; } |
| |
| private: |
| // During shadowing, the currently shadowing label. After shadowing, the |
| // label that was shadowed. |
| Label* original_label_; |
| |
| // During shadowing, the saved state of the original label. |
| int original_pos_; |
| |
| #ifdef DEBUG |
| bool is_shadowing_; |
| #endif |
| }; |
| |
| |
| // ----------------------------------------------------------------------------- |
| // 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 BASE_EMBEDDED { |
| 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; |
| |
| enum Mode { |
| // Please note the order is important (see IsCodeTarget, IsGCRelocMode). |
| CONSTRUCT_CALL, // code target that is a call to a JavaScript constructor. |
| CODE_TARGET_CONTEXT, // code target used for contextual loads. |
| CODE_TARGET, // code target which is not any of the above. |
| EMBEDDED_OBJECT, |
| EMBEDDED_STRING, |
| |
| // 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. |
| EXTERNAL_REFERENCE, // The address of an external C++ function. |
| INTERNAL_REFERENCE, // An address inside the same function. |
| |
| // add more as needed |
| // Pseudo-types |
| NUMBER_OF_MODES, // must be no greater than 14 - see RelocInfoWriter |
| NONE, // never recorded |
| LAST_CODE_ENUM = CODE_TARGET, |
| LAST_GCED_ENUM = EMBEDDED_STRING |
| }; |
| |
| |
| RelocInfo() {} |
| RelocInfo(byte* pc, Mode rmode, intptr_t data) |
| : pc_(pc), rmode_(rmode), data_(data) { |
| } |
| |
| static inline bool IsConstructCall(Mode mode) { |
| return mode == CONSTRUCT_CALL; |
| } |
| static inline bool IsCodeTarget(Mode mode) { |
| return mode <= LAST_CODE_ENUM; |
| } |
| // 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 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 int ModeMask(Mode mode) { return 1 << mode; } |
| |
| // Accessors |
| byte* pc() const { return pc_; } |
| void set_pc(byte* pc) { pc_ = pc; } |
| Mode rmode() const { return rmode_; } |
| intptr_t data() const { return data_; } |
| |
| // Apply a relocation by delta bytes |
| INLINE(void apply(int delta)); |
| |
| // Read/modify the code target in the branch/call instruction |
| // this relocation applies to; |
| // can only be called if IsCodeTarget(rmode_) || rmode_ == RUNTIME_ENTRY |
| INLINE(Address target_address()); |
| INLINE(void set_target_address(Address target)); |
| INLINE(Object* target_object()); |
| INLINE(Object** target_object_address()); |
| INLINE(void set_target_object(Object* target)); |
| |
| // Read the address of the word containing the target_address. Can only |
| // be called if IsCodeTarget(rmode_) || rmode_ == RUNTIME_ENTRY. |
| INLINE(Address target_address_address()); |
| |
| // Read/modify the reference in the instruction this relocation |
| // applies to; can only be called if rmode_ is external_reference |
| INLINE(Address* target_reference_address()); |
| |
| // 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(Object** call_object_address()); |
| INLINE(void set_call_object(Object* target)); |
| |
| // 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); |
| INLINE(bool IsCallInstruction()); |
| |
| #ifdef ENABLE_DISASSEMBLER |
| // Printing |
| static const char* RelocModeName(Mode rmode); |
| void Print(); |
| #endif // ENABLE_DISASSEMBLER |
| #ifdef DEBUG |
| // Debugging |
| void Verify(); |
| #endif |
| |
| static const int kCodeTargetMask = (1 << (LAST_CODE_ENUM + 1)) - 1; |
| static const int kPositionMask = 1 << POSITION | 1 << STATEMENT_POSITION; |
| static const int kDebugMask = 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_; |
| intptr_t data_; |
| 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_data_(0) {} |
| RelocInfoWriter(byte* pos, byte* pc) : pos_(pos), last_pc_(pc), |
| last_data_(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. |
| static const int kMaxSize = 12; |
| |
| 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 WriteExtraTaggedData(int32_t data_delta, int top_tag); |
| inline void WriteTaggedData(int32_t data_delta, int tag); |
| inline void WriteExtraTag(int extra_tag, int top_tag); |
| |
| byte* pos_; |
| byte* last_pc_; |
| intptr_t last_data_; |
| 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() { |
| ASSERT(!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 AdvanceReadData(); |
| void AdvanceReadVariableLengthPCJump(); |
| int GetPositionTypeTag(); |
| void ReadTaggedData(); |
| |
| static RelocInfo::Mode DebugInfoModeFromTag(int tag); |
| |
| // 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_; |
| RelocInfo rinfo_; |
| bool done_; |
| int mode_mask_; |
| DISALLOW_COPY_AND_ASSIGN(RelocIterator); |
| }; |
| |
| |
| // A stack-allocated code region logs a name for the code generated |
| // while the region is in effect. This information is used by the |
| // profiler to categorize ticks within generated code. |
| class CodeRegion BASE_EMBEDDED { |
| public: |
| inline CodeRegion(Assembler* assm, const char *name) : assm_(assm) { |
| LOG(BeginCodeRegionEvent(this, assm, name)); |
| } |
| inline ~CodeRegion() { |
| LOG(EndCodeRegionEvent(this, assm_)); |
| } |
| private: |
| Assembler* assm_; |
| }; |
| |
| |
| //------------------------------------------------------------------------------ |
| // External function |
| |
| //---------------------------------------------------------------------------- |
| class IC_Utility; |
| class Debug_Address; |
| class SCTableReference; |
| |
| // An ExternalReference represents a C++ address called from the generated |
| // code. All references to C++ functions and must be encapsulated in an |
| // ExternalReference instance. This is done in order to track the origin of |
| // all external references in the code. |
| class ExternalReference BASE_EMBEDDED { |
| public: |
| explicit ExternalReference(Builtins::CFunctionId id); |
| |
| explicit ExternalReference(Builtins::Name name); |
| |
| explicit ExternalReference(Runtime::FunctionId id); |
| |
| explicit ExternalReference(Runtime::Function* f); |
| |
| explicit ExternalReference(const IC_Utility& ic_utility); |
| |
| explicit ExternalReference(const Debug_Address& debug_address); |
| |
| explicit ExternalReference(StatsCounter* counter); |
| |
| explicit ExternalReference(Top::AddressId id); |
| |
| explicit ExternalReference(const SCTableReference& table_ref); |
| |
| // 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 builtin_passed_function(); |
| |
| // Static variable Factory::the_hole_value.location() |
| static ExternalReference the_hole_value_location(); |
| |
| // Static variable StackGuard::address_of_jslimit() |
| static ExternalReference address_of_stack_guard_limit(); |
| |
| // Static variable RegExpStack::limit_address() |
| static ExternalReference address_of_regexp_stack_limit(); |
| |
| // Function Debug::Break() |
| static ExternalReference debug_break(); |
| |
| // Static variable Heap::NewSpaceStart() |
| static ExternalReference new_space_start(); |
| static ExternalReference heap_always_allocate_scope_depth(); |
| |
| // Used for fast allocation in generated code. |
| static ExternalReference new_space_allocation_top_address(); |
| static ExternalReference new_space_allocation_limit_address(); |
| |
| // Used to check if single stepping is enabled in generated code. |
| static ExternalReference debug_step_in_fp_address(); |
| |
| Address address() const {return address_;} |
| |
| private: |
| explicit ExternalReference(void* address) |
| : address_(reinterpret_cast<Address>(address)) {} |
| |
| Address address_; |
| }; |
| |
| |
| // ----------------------------------------------------------------------------- |
| // Utility functions |
| |
| // Move these into inline file? |
| |
| static inline bool is_intn(int x, int n) { |
| return -(1 << (n-1)) <= x && x < (1 << (n-1)); |
| } |
| |
| static inline bool is_int24(int x) { return is_intn(x, 24); } |
| static inline bool is_int8(int x) { return is_intn(x, 8); } |
| |
| static inline bool is_uintn(int x, int n) { |
| return (x & -(1 << n)) == 0; |
| } |
| |
| static inline bool is_uint3(int x) { return is_uintn(x, 3); } |
| static inline bool is_uint4(int x) { return is_uintn(x, 4); } |
| static inline bool is_uint5(int x) { return is_uintn(x, 5); } |
| static inline bool is_uint8(int x) { return is_uintn(x, 8); } |
| static inline bool is_uint12(int x) { return is_uintn(x, 12); } |
| static inline bool is_uint16(int x) { return is_uintn(x, 16); } |
| static inline bool is_uint24(int x) { return is_uintn(x, 24); } |
| |
| } } // namespace v8::internal |
| |
| #endif // V8_ASSEMBLER_H_ |