michael@0: /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
michael@0:  * vim: set ts=8 sts=4 et sw=4 tw=99:
michael@0:  * This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #ifndef jsopcode_h
michael@0: #define jsopcode_h
michael@0: 
michael@0: /*
michael@0:  * JS bytecode definitions.
michael@0:  */
michael@0: 
michael@0: #include "jsbytecode.h"
michael@0: #include "jstypes.h"
michael@0: #include "NamespaceImports.h"
michael@0: 
michael@0: #include "frontend/SourceNotes.h"
michael@0: #include "vm/Opcodes.h"
michael@0: 
michael@0: /*
michael@0:  * JS operation bytecodes.
michael@0:  */
michael@0: typedef enum JSOp {
michael@0: #define ENUMERATE_OPCODE(op, val, ...) op = val,
michael@0: FOR_EACH_OPCODE(ENUMERATE_OPCODE)
michael@0: #undef ENUMERATE_OPCODE
michael@0: 
michael@0:     JSOP_LIMIT,
michael@0: 
michael@0:     /*
michael@0:      * These pseudo-ops help js_DecompileValueGenerator decompile JSOP_SETPROP,
michael@0:      * JSOP_SETELEM, and comprehension-tails, respectively.  They are never
michael@0:      * stored in bytecode, so they don't preempt valid opcodes.
michael@0:      */
michael@0:     JSOP_GETPROP2 = JSOP_LIMIT,
michael@0:     JSOP_GETELEM2 = JSOP_LIMIT + 1,
michael@0:     JSOP_FORLOCAL = JSOP_LIMIT + 2,
michael@0:     JSOP_FAKE_LIMIT = JSOP_FORLOCAL
michael@0: } JSOp;
michael@0: 
michael@0: /*
michael@0:  * JS bytecode formats.
michael@0:  */
michael@0: #define JOF_BYTE          0       /* single bytecode, no immediates */
michael@0: #define JOF_JUMP          1       /* signed 16-bit jump offset immediate */
michael@0: #define JOF_ATOM          2       /* unsigned 16-bit constant index */
michael@0: #define JOF_UINT16        3       /* unsigned 16-bit immediate operand */
michael@0: #define JOF_TABLESWITCH   4       /* table switch */
michael@0: /* 5 is unused */
michael@0: #define JOF_QARG          6       /* quickened get/set function argument ops */
michael@0: #define JOF_LOCAL         7       /* var or block-local variable */
michael@0: #define JOF_DOUBLE        8       /* uint32_t index for double value */
michael@0: #define JOF_UINT24        12      /* extended unsigned 24-bit literal (index) */
michael@0: #define JOF_UINT8         13      /* uint8_t immediate, e.g. top 8 bits of 24-bit
michael@0:                                      atom index */
michael@0: #define JOF_INT32         14      /* int32_t immediate operand */
michael@0: #define JOF_OBJECT        15      /* unsigned 16-bit object index */
michael@0: /* 16 is unused */
michael@0: #define JOF_REGEXP        17      /* unsigned 32-bit regexp index */
michael@0: #define JOF_INT8          18      /* int8_t immediate operand */
michael@0: #define JOF_ATOMOBJECT    19      /* uint16_t constant index + object index */
michael@0: /* 20 is unused */
michael@0: #define JOF_SCOPECOORD    21      /* embedded ScopeCoordinate immediate */
michael@0: #define JOF_TYPEMASK      0x001f  /* mask for above immediate types */
michael@0: 
michael@0: #define JOF_NAME          (1U<<5) /* name operation */
michael@0: #define JOF_PROP          (2U<<5) /* obj.prop operation */
michael@0: #define JOF_ELEM          (3U<<5) /* obj[index] operation */
michael@0: #define JOF_MODEMASK      (7U<<5) /* mask for above addressing modes */
michael@0: #define JOF_SET           (1U<<8) /* set (i.e., assignment) operation */
michael@0: /* (1U<<9) is unused*/
michael@0: /* (1U<<10) is unused*/
michael@0: /* (1U<<11) is unused*/
michael@0: /* (1U<<12) is unused*/
michael@0: /* (1U<<13) is unused*/
michael@0: #define JOF_DETECTING    (1U<<14) /* object detection for warning-quelling */
michael@0: /* (1U<<15) is unused*/
michael@0: #define JOF_LEFTASSOC    (1U<<16) /* left-associative operator */
michael@0: /* (1U<<17) is unused */
michael@0: /* (1U<<18) is unused */
michael@0: /* (1U<<19) is unused*/
michael@0: /* (1U<<20) is unused*/
michael@0: #define JOF_INVOKE       (1U<<21) /* JSOP_CALL, JSOP_FUNCALL, JSOP_FUNAPPLY,
michael@0:                                      JSOP_NEW, JSOP_EVAL */
michael@0: #define JOF_TMPSLOT      (1U<<22) /* interpreter uses extra temporary slot
michael@0:                                      to root intermediate objects besides
michael@0:                                      the slots opcode uses */
michael@0: #define JOF_TMPSLOT2     (2U<<22) /* interpreter uses extra 2 temporary slot
michael@0:                                      besides the slots opcode uses */
michael@0: #define JOF_TMPSLOT3     (3U<<22) /* interpreter uses extra 3 temporary slot
michael@0:                                      besides the slots opcode uses */
michael@0: #define JOF_TMPSLOT_SHIFT 22
michael@0: #define JOF_TMPSLOT_MASK  (JS_BITMASK(2) << JOF_TMPSLOT_SHIFT)
michael@0: 
michael@0: /* (1U<<24) is unused */
michael@0: #define JOF_GNAME        (1U<<25) /* predicted global name */
michael@0: #define JOF_TYPESET      (1U<<26) /* has an entry in a script's type sets */
michael@0: #define JOF_ARITH        (1U<<27) /* unary or binary arithmetic opcode */
michael@0: 
michael@0: /* Shorthands for type from format and type from opcode. */
michael@0: #define JOF_TYPE(fmt)   ((fmt) & JOF_TYPEMASK)
michael@0: #define JOF_OPTYPE(op)  JOF_TYPE(js_CodeSpec[op].format)
michael@0: 
michael@0: /* Shorthands for mode from format and mode from opcode. */
michael@0: #define JOF_MODE(fmt)   ((fmt) & JOF_MODEMASK)
michael@0: #define JOF_OPMODE(op)  JOF_MODE(js_CodeSpec[op].format)
michael@0: 
michael@0: /*
michael@0:  * Immediate operand getters, setters, and bounds.
michael@0:  */
michael@0: 
michael@0: static MOZ_ALWAYS_INLINE uint8_t
michael@0: GET_UINT8(jsbytecode *pc)
michael@0: {
michael@0:     return (uint8_t) pc[1];
michael@0: }
michael@0: 
michael@0: static MOZ_ALWAYS_INLINE void
michael@0: SET_UINT8(jsbytecode *pc, uint8_t u)
michael@0: {
michael@0:     pc[1] = (jsbytecode) u;
michael@0: }
michael@0: 
michael@0: /* Common uint16_t immediate format helpers. */
michael@0: #define UINT16_LEN              2
michael@0: #define UINT16_HI(i)            ((jsbytecode)((i) >> 8))
michael@0: #define UINT16_LO(i)            ((jsbytecode)(i))
michael@0: #define GET_UINT16(pc)          ((unsigned)(((pc)[1] << 8) | (pc)[2]))
michael@0: #define SET_UINT16(pc,i)        ((pc)[1] = UINT16_HI(i), (pc)[2] = UINT16_LO(i))
michael@0: #define UINT16_LIMIT            ((unsigned)1 << 16)
michael@0: 
michael@0: /* Helpers for accessing the offsets of jump opcodes. */
michael@0: #define JUMP_OFFSET_LEN         4
michael@0: #define JUMP_OFFSET_MIN         INT32_MIN
michael@0: #define JUMP_OFFSET_MAX         INT32_MAX
michael@0: 
michael@0: static MOZ_ALWAYS_INLINE int32_t
michael@0: GET_JUMP_OFFSET(jsbytecode *pc)
michael@0: {
michael@0:     return (pc[1] << 24) | (pc[2] << 16) | (pc[3] << 8) | pc[4];
michael@0: }
michael@0: 
michael@0: static MOZ_ALWAYS_INLINE void
michael@0: SET_JUMP_OFFSET(jsbytecode *pc, int32_t off)
michael@0: {
michael@0:     pc[1] = (jsbytecode)(off >> 24);
michael@0:     pc[2] = (jsbytecode)(off >> 16);
michael@0:     pc[3] = (jsbytecode)(off >> 8);
michael@0:     pc[4] = (jsbytecode)off;
michael@0: }
michael@0: 
michael@0: #define UINT32_INDEX_LEN        4
michael@0: 
michael@0: static MOZ_ALWAYS_INLINE uint32_t
michael@0: GET_UINT32_INDEX(const jsbytecode *pc)
michael@0: {
michael@0:     return (pc[1] << 24) | (pc[2] << 16) | (pc[3] << 8) | pc[4];
michael@0: }
michael@0: 
michael@0: static MOZ_ALWAYS_INLINE void
michael@0: SET_UINT32_INDEX(jsbytecode *pc, uint32_t index)
michael@0: {
michael@0:     pc[1] = (jsbytecode)(index >> 24);
michael@0:     pc[2] = (jsbytecode)(index >> 16);
michael@0:     pc[3] = (jsbytecode)(index >> 8);
michael@0:     pc[4] = (jsbytecode)index;
michael@0: }
michael@0: 
michael@0: #define UINT24_HI(i)            ((jsbytecode)((i) >> 16))
michael@0: #define UINT24_MID(i)           ((jsbytecode)((i) >> 8))
michael@0: #define UINT24_LO(i)            ((jsbytecode)(i))
michael@0: #define GET_UINT24(pc)          ((unsigned)(((pc)[1] << 16) |                 \
michael@0:                                             ((pc)[2] << 8) |                  \
michael@0:                                             (pc)[3]))
michael@0: #define SET_UINT24(pc,i)        ((pc)[1] = UINT24_HI(i),                      \
michael@0:                                  (pc)[2] = UINT24_MID(i),                     \
michael@0:                                  (pc)[3] = UINT24_LO(i))
michael@0: 
michael@0: #define GET_INT8(pc)            (int8_t((pc)[1]))
michael@0: 
michael@0: #define GET_INT32(pc)           (((uint32_t((pc)[1]) << 24) |                 \
michael@0:                                   (uint32_t((pc)[2]) << 16) |                 \
michael@0:                                   (uint32_t((pc)[3]) << 8)  |                 \
michael@0:                                   uint32_t((pc)[4])))
michael@0: #define SET_INT32(pc,i)         ((pc)[1] = (jsbytecode)(uint32_t(i) >> 24),   \
michael@0:                                  (pc)[2] = (jsbytecode)(uint32_t(i) >> 16),   \
michael@0:                                  (pc)[3] = (jsbytecode)(uint32_t(i) >> 8),    \
michael@0:                                  (pc)[4] = (jsbytecode)uint32_t(i))
michael@0: 
michael@0: /* Index limit is determined by SN_4BYTE_OFFSET_FLAG, see frontend/BytecodeEmitter.h. */
michael@0: #define INDEX_LIMIT_LOG2        31
michael@0: #define INDEX_LIMIT             (uint32_t(1) << INDEX_LIMIT_LOG2)
michael@0: 
michael@0: #define ARGC_HI(argc)           UINT16_HI(argc)
michael@0: #define ARGC_LO(argc)           UINT16_LO(argc)
michael@0: #define GET_ARGC(pc)            GET_UINT16(pc)
michael@0: #define ARGC_LIMIT              UINT16_LIMIT
michael@0: 
michael@0: #define GET_ARGNO(pc)           GET_UINT16(pc)
michael@0: #define SET_ARGNO(pc,argno)     SET_UINT16(pc,argno)
michael@0: #define ARGNO_LEN               2
michael@0: #define ARGNO_LIMIT             UINT16_LIMIT
michael@0: 
michael@0: #define GET_LOCALNO(pc)         GET_UINT24(pc)
michael@0: #define SET_LOCALNO(pc,varno)   SET_UINT24(pc,varno)
michael@0: #define LOCALNO_LEN             3
michael@0: #define LOCALNO_BITS            24
michael@0: #define LOCALNO_LIMIT           (1 << LOCALNO_BITS)
michael@0: 
michael@0: static inline unsigned
michael@0: LoopEntryDepthHint(jsbytecode *pc)
michael@0: {
michael@0:     JS_ASSERT(*pc == JSOP_LOOPENTRY);
michael@0:     return GET_UINT8(pc) & 0x7f;
michael@0: }
michael@0: static inline bool
michael@0: LoopEntryCanIonOsr(jsbytecode *pc)
michael@0: {
michael@0:     JS_ASSERT(*pc == JSOP_LOOPENTRY);
michael@0:     return GET_UINT8(pc) & 0x80;
michael@0: }
michael@0: static inline uint8_t
michael@0: PackLoopEntryDepthHintAndFlags(unsigned loopDepth, bool canIonOsr)
michael@0: {
michael@0:     return (loopDepth < 0x80 ? uint8_t(loopDepth) : 0x7f) | (canIonOsr ? 0x80 : 0);
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * Describes the 'hops' component of a JOF_SCOPECOORD opcode.
michael@0:  *
michael@0:  * Note: this component is only 8 bits wide, limiting the maximum number of
michael@0:  * scopes between a use and def to roughly 255. This is a pretty small limit but
michael@0:  * note that SpiderMonkey's recursive descent parser can only parse about this
michael@0:  * many functions before hitting the C-stack recursion limit so this shouldn't
michael@0:  * be a significant limitation in practice.
michael@0:  */
michael@0: #define GET_SCOPECOORD_HOPS(pc) GET_UINT8(pc)
michael@0: #define SET_SCOPECOORD_HOPS(pc,hops) SET_UINT8(pc,hops)
michael@0: #define SCOPECOORD_HOPS_LEN     1
michael@0: #define SCOPECOORD_HOPS_BITS    8
michael@0: #define SCOPECOORD_HOPS_LIMIT   (1 << SCOPECOORD_HOPS_BITS)
michael@0: 
michael@0: /* Describes the 'slot' component of a JOF_SCOPECOORD opcode. */
michael@0: #define GET_SCOPECOORD_SLOT(pc) GET_UINT24(pc)
michael@0: #define SET_SCOPECOORD_SLOT(pc,slot) SET_UINT24(pc,slot)
michael@0: #define SCOPECOORD_SLOT_LEN     3
michael@0: #define SCOPECOORD_SLOT_BITS    24
michael@0: #define SCOPECOORD_SLOT_LIMIT   (1 << SCOPECOORD_SLOT_BITS)
michael@0: 
michael@0: struct JSCodeSpec {
michael@0:     int8_t              length;         /* length including opcode byte */
michael@0:     int8_t              nuses;          /* arity, -1 if variadic */
michael@0:     int8_t              ndefs;          /* number of stack results */
michael@0:     uint32_t            format;         /* immediate operand format */
michael@0: 
michael@0:     uint32_t type() const { return JOF_TYPE(format); }
michael@0: };
michael@0: 
michael@0: extern const JSCodeSpec js_CodeSpec[];
michael@0: extern const unsigned   js_NumCodeSpecs;
michael@0: extern const char       * const js_CodeName[];
michael@0: extern const char       js_EscapeMap[];
michael@0: 
michael@0: /* Silence unreferenced formal parameter warnings */
michael@0: #ifdef _MSC_VER
michael@0: #pragma warning(push)
michael@0: #pragma warning(disable:4100)
michael@0: #endif
michael@0: 
michael@0: /*
michael@0:  * Return a GC'ed string containing the chars in str, with any non-printing
michael@0:  * chars or quotes (' or " as specified by the quote argument) escaped, and
michael@0:  * with the quote character at the beginning and end of the result string.
michael@0:  */
michael@0: extern JSString *
michael@0: js_QuoteString(js::ExclusiveContext *cx, JSString *str, jschar quote);
michael@0: 
michael@0: namespace js {
michael@0: 
michael@0: static inline bool
michael@0: IsJumpOpcode(JSOp op)
michael@0: {
michael@0:     uint32_t type = JOF_TYPE(js_CodeSpec[op].format);
michael@0: 
michael@0:     /*
michael@0:      * LABEL opcodes have type JOF_JUMP but are no-ops, don't treat them as
michael@0:      * jumps to avoid degrading precision.
michael@0:      */
michael@0:     return type == JOF_JUMP && op != JSOP_LABEL;
michael@0: }
michael@0: 
michael@0: static inline bool
michael@0: BytecodeFallsThrough(JSOp op)
michael@0: {
michael@0:     switch (op) {
michael@0:       case JSOP_GOTO:
michael@0:       case JSOP_DEFAULT:
michael@0:       case JSOP_RETURN:
michael@0:       case JSOP_RETRVAL:
michael@0:       case JSOP_THROW:
michael@0:       case JSOP_TABLESWITCH:
michael@0:         return false;
michael@0:       case JSOP_GOSUB:
michael@0:         /* These fall through indirectly, after executing a 'finally'. */
michael@0:         return true;
michael@0:       default:
michael@0:         return true;
michael@0:     }
michael@0: }
michael@0: 
michael@0: class SrcNoteLineScanner
michael@0: {
michael@0:     /* offset of the current JSOp in the bytecode */
michael@0:     ptrdiff_t offset;
michael@0: 
michael@0:     /* next src note to process */
michael@0:     jssrcnote *sn;
michael@0: 
michael@0:     /* line number of the current JSOp */
michael@0:     uint32_t lineno;
michael@0: 
michael@0:     /*
michael@0:      * Is the current op the first one after a line change directive? Note that
michael@0:      * multiple ops may be "first" if a line directive is used to return to a
michael@0:      * previous line (eg, with a for loop increment expression.)
michael@0:      */
michael@0:     bool lineHeader;
michael@0: 
michael@0: public:
michael@0:     SrcNoteLineScanner(jssrcnote *sn, uint32_t lineno)
michael@0:         : offset(0), sn(sn), lineno(lineno)
michael@0:     {
michael@0:     }
michael@0: 
michael@0:     /*
michael@0:      * This is called repeatedly with always-advancing relpc values. The src
michael@0:      * notes are tuples of <PC offset from prev src note, type, args>. Scan
michael@0:      * through, updating the lineno, until the next src note is for a later
michael@0:      * bytecode.
michael@0:      *
michael@0:      * When looking at the desired PC offset ('relpc'), the op is first in that
michael@0:      * line iff there is a SRC_SETLINE or SRC_NEWLINE src note for that exact
michael@0:      * bytecode.
michael@0:      *
michael@0:      * Note that a single bytecode may have multiple line-modifying notes (even
michael@0:      * though only one should ever be needed.)
michael@0:      */
michael@0:     void advanceTo(ptrdiff_t relpc) {
michael@0:         // Must always advance! If the same or an earlier PC is erroneously
michael@0:         // passed in, we will already be past the relevant src notes
michael@0:         JS_ASSERT_IF(offset > 0, relpc > offset);
michael@0: 
michael@0:         // Next src note should be for after the current offset
michael@0:         JS_ASSERT_IF(offset > 0, SN_IS_TERMINATOR(sn) || SN_DELTA(sn) > 0);
michael@0: 
michael@0:         // The first PC requested is always considered to be a line header
michael@0:         lineHeader = (offset == 0);
michael@0: 
michael@0:         if (SN_IS_TERMINATOR(sn))
michael@0:             return;
michael@0: 
michael@0:         ptrdiff_t nextOffset;
michael@0:         while ((nextOffset = offset + SN_DELTA(sn)) <= relpc && !SN_IS_TERMINATOR(sn)) {
michael@0:             offset = nextOffset;
michael@0:             SrcNoteType type = (SrcNoteType) SN_TYPE(sn);
michael@0:             if (type == SRC_SETLINE || type == SRC_NEWLINE) {
michael@0:                 if (type == SRC_SETLINE)
michael@0:                     lineno = js_GetSrcNoteOffset(sn, 0);
michael@0:                 else
michael@0:                     lineno++;
michael@0: 
michael@0:                 if (offset == relpc)
michael@0:                     lineHeader = true;
michael@0:             }
michael@0: 
michael@0:             sn = SN_NEXT(sn);
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     bool isLineHeader() const {
michael@0:         return lineHeader;
michael@0:     }
michael@0: 
michael@0:     uint32_t getLine() const { return lineno; }
michael@0: };
michael@0: 
michael@0: extern unsigned
michael@0: StackUses(JSScript *script, jsbytecode *pc);
michael@0: 
michael@0: extern unsigned
michael@0: StackDefs(JSScript *script, jsbytecode *pc);
michael@0: 
michael@0: #ifdef DEBUG
michael@0: /*
michael@0:  * Given bytecode address pc in script's main program code, compute the operand
michael@0:  * stack depth just before (JSOp) *pc executes.  If *pc is not reachable, return
michael@0:  * false.
michael@0:  */
michael@0: extern bool
michael@0: ReconstructStackDepth(JSContext *cx, JSScript *script, jsbytecode *pc, uint32_t *depth, bool *reachablePC);
michael@0: #endif
michael@0: 
michael@0: }  /* namespace js */
michael@0: 
michael@0: #ifdef _MSC_VER
michael@0: #pragma warning(pop)
michael@0: #endif
michael@0: 
michael@0: #define JSDVG_IGNORE_STACK      0
michael@0: #define JSDVG_SEARCH_STACK      1
michael@0: 
michael@0: /*
michael@0:  * Get the length of variable-length bytecode like JSOP_TABLESWITCH.
michael@0:  */
michael@0: extern size_t
michael@0: js_GetVariableBytecodeLength(jsbytecode *pc);
michael@0: 
michael@0: namespace js {
michael@0: 
michael@0: /*
michael@0:  * Find the source expression that resulted in v, and return a newly allocated
michael@0:  * C-string containing it.  Fall back on v's string conversion (fallback) if we
michael@0:  * can't find the bytecode that generated and pushed v on the operand stack.
michael@0:  *
michael@0:  * Search the current stack frame if spindex is JSDVG_SEARCH_STACK.  Don't
michael@0:  * look for v on the stack if spindex is JSDVG_IGNORE_STACK.  Otherwise,
michael@0:  * spindex is the negative index of v, measured from cx->fp->sp, or from a
michael@0:  * lower frame's sp if cx->fp is native.
michael@0:  *
michael@0:  * The optional argument skipStackHits can be used to skip a hit in the stack
michael@0:  * frame. This can be useful in self-hosted code that wants to report value
michael@0:  * errors containing decompiled values that are useful for the user, instead of
michael@0:  * values used internally by the self-hosted code.
michael@0:  *
michael@0:  * The caller must call JS_free on the result after a successful call.
michael@0:  */
michael@0: char *
michael@0: DecompileValueGenerator(JSContext *cx, int spindex, HandleValue v,
michael@0:                         HandleString fallback, int skipStackHits = 0);
michael@0: 
michael@0: /*
michael@0:  * Decompile the formal argument at formalIndex in the nearest non-builtin
michael@0:  * stack frame, falling back with converting v to source.
michael@0:  */
michael@0: char *
michael@0: DecompileArgument(JSContext *cx, int formalIndex, HandleValue v);
michael@0: 
michael@0: /*
michael@0:  * Sprintf, but with unlimited and automatically allocated buffering.
michael@0:  */
michael@0: class Sprinter
michael@0: {
michael@0:   public:
michael@0:     struct InvariantChecker
michael@0:     {
michael@0:         const Sprinter *parent;
michael@0: 
michael@0:         explicit InvariantChecker(const Sprinter *p) : parent(p) {
michael@0:             parent->checkInvariants();
michael@0:         }
michael@0: 
michael@0:         ~InvariantChecker() {
michael@0:             parent->checkInvariants();
michael@0:         }
michael@0:     };
michael@0: 
michael@0:     ExclusiveContext        *context;       /* context executing the decompiler */
michael@0: 
michael@0:   private:
michael@0:     static const size_t     DefaultSize;
michael@0: #ifdef DEBUG
michael@0:     bool                    initialized;    /* true if this is initialized, use for debug builds */
michael@0: #endif
michael@0:     char                    *base;          /* malloc'd buffer address */
michael@0:     size_t                  size;           /* size of buffer allocated at base */
michael@0:     ptrdiff_t               offset;         /* offset of next free char in buffer */
michael@0:     bool                    reportedOOM;    /* this sprinter has reported OOM in string ops */
michael@0: 
michael@0:     bool realloc_(size_t newSize);
michael@0: 
michael@0:   public:
michael@0:     explicit Sprinter(ExclusiveContext *cx);
michael@0:     ~Sprinter();
michael@0: 
michael@0:     /* Initialize this sprinter, returns false on error */
michael@0:     bool init();
michael@0: 
michael@0:     void checkInvariants() const;
michael@0: 
michael@0:     const char *string() const;
michael@0:     const char *stringEnd() const;
michael@0:     /* Returns the string at offset |off| */
michael@0:     char *stringAt(ptrdiff_t off) const;
michael@0:     /* Returns the char at offset |off| */
michael@0:     char &operator[](size_t off);
michael@0: 
michael@0:     /*
michael@0:      * Attempt to reserve len + 1 space (for a trailing nullptr byte). If the
michael@0:      * attempt succeeds, return a pointer to the start of that space and adjust the
michael@0:      * internal content. The caller *must* completely fill this space on success.
michael@0:      */
michael@0:     char *reserve(size_t len);
michael@0: 
michael@0:     /*
michael@0:      * Puts |len| characters from |s| at the current position and return an offset to
michael@0:      * the beginning of this new data
michael@0:      */
michael@0:     ptrdiff_t put(const char *s, size_t len);
michael@0:     ptrdiff_t put(const char *s);
michael@0:     ptrdiff_t putString(JSString *str);
michael@0: 
michael@0:     /* Prints a formatted string into the buffer */
michael@0:     int printf(const char *fmt, ...);
michael@0: 
michael@0:     ptrdiff_t getOffset() const;
michael@0: 
michael@0:     /*
michael@0:      * Report that a string operation failed to get the memory it requested. The
michael@0:      * first call to this function calls JS_ReportOutOfMemory, and sets this
michael@0:      * Sprinter's outOfMemory flag; subsequent calls do nothing.
michael@0:      */
michael@0:     void reportOutOfMemory();
michael@0: 
michael@0:     /* Return true if this Sprinter ran out of memory. */
michael@0:     bool hadOutOfMemory() const;
michael@0: };
michael@0: 
michael@0: extern ptrdiff_t
michael@0: Sprint(Sprinter *sp, const char *format, ...);
michael@0: 
michael@0: extern bool
michael@0: CallResultEscapes(jsbytecode *pc);
michael@0: 
michael@0: static inline unsigned
michael@0: GetDecomposeLength(jsbytecode *pc, size_t len)
michael@0: {
michael@0:     /*
michael@0:      * The last byte of a DECOMPOSE op stores the decomposed length.  This is a
michael@0:      * constant: perhaps we should just hardcode values instead?
michael@0:      */
michael@0:     JS_ASSERT(size_t(js_CodeSpec[*pc].length) == len);
michael@0:     return (unsigned) pc[len - 1];
michael@0: }
michael@0: 
michael@0: static inline unsigned
michael@0: GetBytecodeLength(jsbytecode *pc)
michael@0: {
michael@0:     JSOp op = (JSOp)*pc;
michael@0:     JS_ASSERT(op < JSOP_LIMIT);
michael@0: 
michael@0:     if (js_CodeSpec[op].length != -1)
michael@0:         return js_CodeSpec[op].length;
michael@0:     return js_GetVariableBytecodeLength(pc);
michael@0: }
michael@0: 
michael@0: static inline bool
michael@0: BytecodeIsPopped(jsbytecode *pc)
michael@0: {
michael@0:     jsbytecode *next = pc + GetBytecodeLength(pc);
michael@0:     return JSOp(*next) == JSOP_POP;
michael@0: }
michael@0: 
michael@0: static inline bool
michael@0: BytecodeFlowsToBitop(jsbytecode *pc)
michael@0: {
michael@0:     // Look for simple bytecode for integer conversions like (x | 0) or (x & -1).
michael@0:     jsbytecode *next = pc + GetBytecodeLength(pc);
michael@0:     if (*next == JSOP_BITOR || *next == JSOP_BITAND)
michael@0:         return true;
michael@0:     if (*next == JSOP_INT8 && GET_INT8(next) == -1) {
michael@0:         next += GetBytecodeLength(next);
michael@0:         if (*next == JSOP_BITAND)
michael@0:             return true;
michael@0:         return false;
michael@0:     }
michael@0:     if (*next == JSOP_ONE) {
michael@0:         next += GetBytecodeLength(next);
michael@0:         if (*next == JSOP_NEG) {
michael@0:             next += GetBytecodeLength(next);
michael@0:             if (*next == JSOP_BITAND)
michael@0:                 return true;
michael@0:         }
michael@0:         return false;
michael@0:     }
michael@0:     if (*next == JSOP_ZERO) {
michael@0:         next += GetBytecodeLength(next);
michael@0:         if (*next == JSOP_BITOR)
michael@0:             return true;
michael@0:         return false;
michael@0:     }
michael@0:     return false;
michael@0: }
michael@0: 
michael@0: extern bool
michael@0: IsValidBytecodeOffset(JSContext *cx, JSScript *script, size_t offset);
michael@0: 
michael@0: inline bool
michael@0: FlowsIntoNext(JSOp op)
michael@0: {
michael@0:     /* JSOP_YIELD is considered to flow into the next instruction, like JSOP_CALL. */
michael@0:     return op != JSOP_RETRVAL && op != JSOP_RETURN && op != JSOP_THROW &&
michael@0:            op != JSOP_GOTO && op != JSOP_RETSUB;
michael@0: }
michael@0: 
michael@0: inline bool
michael@0: IsArgOp(JSOp op)
michael@0: {
michael@0:     return JOF_OPTYPE(op) == JOF_QARG;
michael@0: }
michael@0: 
michael@0: inline bool
michael@0: IsLocalOp(JSOp op)
michael@0: {
michael@0:     return JOF_OPTYPE(op) == JOF_LOCAL;
michael@0: }
michael@0: 
michael@0: inline bool
michael@0: IsAliasedVarOp(JSOp op)
michael@0: {
michael@0:     return JOF_OPTYPE(op) == JOF_SCOPECOORD;
michael@0: }
michael@0: 
michael@0: inline bool
michael@0: IsGlobalOp(JSOp op)
michael@0: {
michael@0:     return js_CodeSpec[op].format & JOF_GNAME;
michael@0: }
michael@0: 
michael@0: inline bool
michael@0: IsEqualityOp(JSOp op)
michael@0: {
michael@0:     return op == JSOP_EQ || op == JSOP_NE || op == JSOP_STRICTEQ || op == JSOP_STRICTNE;
michael@0: }
michael@0: 
michael@0: inline bool
michael@0: IsGetPropPC(jsbytecode *pc)
michael@0: {
michael@0:     JSOp op = JSOp(*pc);
michael@0:     return op == JSOP_LENGTH  || op == JSOP_GETPROP || op == JSOP_CALLPROP;
michael@0: }
michael@0: 
michael@0: inline bool
michael@0: IsSetPropPC(jsbytecode *pc)
michael@0: {
michael@0:     JSOp op = JSOp(*pc);
michael@0:     return op == JSOP_SETPROP || op == JSOP_SETNAME || op == JSOP_SETGNAME;
michael@0: }
michael@0: 
michael@0: inline bool
michael@0: IsGetElemPC(jsbytecode *pc)
michael@0: {
michael@0:     JSOp op = JSOp(*pc);
michael@0:     return op == JSOP_GETELEM || op == JSOP_CALLELEM;
michael@0: }
michael@0: 
michael@0: inline bool
michael@0: IsSetElemPC(jsbytecode *pc)
michael@0: {
michael@0:     JSOp op = JSOp(*pc);
michael@0:     return op == JSOP_SETELEM;
michael@0: }
michael@0: 
michael@0: inline bool
michael@0: IsCallPC(jsbytecode *pc)
michael@0: {
michael@0:     return js_CodeSpec[*pc].format & JOF_INVOKE;
michael@0: }
michael@0: 
michael@0: static inline int32_t
michael@0: GetBytecodeInteger(jsbytecode *pc)
michael@0: {
michael@0:     switch (JSOp(*pc)) {
michael@0:       case JSOP_ZERO:   return 0;
michael@0:       case JSOP_ONE:    return 1;
michael@0:       case JSOP_UINT16: return GET_UINT16(pc);
michael@0:       case JSOP_UINT24: return GET_UINT24(pc);
michael@0:       case JSOP_INT8:   return GET_INT8(pc);
michael@0:       case JSOP_INT32:  return GET_INT32(pc);
michael@0:       default:
michael@0:         MOZ_ASSUME_UNREACHABLE("Bad op");
michael@0:     }
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * Counts accumulated for a single opcode in a script. The counts tracked vary
michael@0:  * between opcodes, and this structure ensures that counts are accessed in a
michael@0:  * coherent fashion.
michael@0:  */
michael@0: class PCCounts
michael@0: {
michael@0:     friend class ::JSScript;
michael@0:     double *counts;
michael@0: #ifdef DEBUG
michael@0:     size_t capacity;
michael@0: #elif JS_BITS_PER_WORD == 32
michael@0:     void *padding;
michael@0: #endif
michael@0: 
michael@0:  public:
michael@0: 
michael@0:     enum BaseCounts {
michael@0:         BASE_INTERP = 0,
michael@0: 
michael@0:         BASE_LIMIT
michael@0:     };
michael@0: 
michael@0:     enum AccessCounts {
michael@0:         ACCESS_MONOMORPHIC = BASE_LIMIT,
michael@0:         ACCESS_DIMORPHIC,
michael@0:         ACCESS_POLYMORPHIC,
michael@0: 
michael@0:         ACCESS_BARRIER,
michael@0:         ACCESS_NOBARRIER,
michael@0: 
michael@0:         ACCESS_UNDEFINED,
michael@0:         ACCESS_NULL,
michael@0:         ACCESS_BOOLEAN,
michael@0:         ACCESS_INT32,
michael@0:         ACCESS_DOUBLE,
michael@0:         ACCESS_STRING,
michael@0:         ACCESS_OBJECT,
michael@0: 
michael@0:         ACCESS_LIMIT
michael@0:     };
michael@0: 
michael@0:     static bool accessOp(JSOp op) {
michael@0:         /*
michael@0:          * Access ops include all name, element and property reads, as well as
michael@0:          * SETELEM and SETPROP (for ElementCounts/PropertyCounts alignment).
michael@0:          */
michael@0:         if (op == JSOP_SETELEM || op == JSOP_SETPROP)
michael@0:             return true;
michael@0:         int format = js_CodeSpec[op].format;
michael@0:         return !!(format & (JOF_NAME | JOF_GNAME | JOF_ELEM | JOF_PROP))
michael@0:             && !(format & JOF_SET);
michael@0:     }
michael@0: 
michael@0:     enum ElementCounts {
michael@0:         ELEM_ID_INT = ACCESS_LIMIT,
michael@0:         ELEM_ID_DOUBLE,
michael@0:         ELEM_ID_OTHER,
michael@0:         ELEM_ID_UNKNOWN,
michael@0: 
michael@0:         ELEM_OBJECT_TYPED,
michael@0:         ELEM_OBJECT_PACKED,
michael@0:         ELEM_OBJECT_DENSE,
michael@0:         ELEM_OBJECT_OTHER,
michael@0: 
michael@0:         ELEM_LIMIT
michael@0:     };
michael@0: 
michael@0:     static bool elementOp(JSOp op) {
michael@0:         return accessOp(op) && (JOF_MODE(js_CodeSpec[op].format) == JOF_ELEM);
michael@0:     }
michael@0: 
michael@0:     enum PropertyCounts {
michael@0:         PROP_STATIC = ACCESS_LIMIT,
michael@0:         PROP_DEFINITE,
michael@0:         PROP_OTHER,
michael@0: 
michael@0:         PROP_LIMIT
michael@0:     };
michael@0: 
michael@0:     static bool propertyOp(JSOp op) {
michael@0:         return accessOp(op) && (JOF_MODE(js_CodeSpec[op].format) == JOF_PROP);
michael@0:     }
michael@0: 
michael@0:     enum ArithCounts {
michael@0:         ARITH_INT = BASE_LIMIT,
michael@0:         ARITH_DOUBLE,
michael@0:         ARITH_OTHER,
michael@0:         ARITH_UNKNOWN,
michael@0: 
michael@0:         ARITH_LIMIT
michael@0:     };
michael@0: 
michael@0:     static bool arithOp(JSOp op) {
michael@0:         return !!(js_CodeSpec[op].format & JOF_ARITH);
michael@0:     }
michael@0: 
michael@0:     static size_t numCounts(JSOp op)
michael@0:     {
michael@0:         if (accessOp(op)) {
michael@0:             if (elementOp(op))
michael@0:                 return ELEM_LIMIT;
michael@0:             if (propertyOp(op))
michael@0:                 return PROP_LIMIT;
michael@0:             return ACCESS_LIMIT;
michael@0:         }
michael@0:         if (arithOp(op))
michael@0:             return ARITH_LIMIT;
michael@0:         return BASE_LIMIT;
michael@0:     }
michael@0: 
michael@0:     static const char *countName(JSOp op, size_t which);
michael@0: 
michael@0:     double *rawCounts() const { return counts; }
michael@0: 
michael@0:     double& get(size_t which) {
michael@0:         JS_ASSERT(which < capacity);
michael@0:         return counts[which];
michael@0:     }
michael@0: 
michael@0:     /* Boolean conversion, for 'if (counters) ...' */
michael@0:     operator void*() const {
michael@0:         return counts;
michael@0:     }
michael@0: };
michael@0: 
michael@0: /* Necessary for alignment with the script. */
michael@0: JS_STATIC_ASSERT(sizeof(PCCounts) % sizeof(Value) == 0);
michael@0: 
michael@0: static inline jsbytecode *
michael@0: GetNextPc(jsbytecode *pc)
michael@0: {
michael@0:     return pc + GetBytecodeLength(pc);
michael@0: }
michael@0: 
michael@0: } /* namespace js */
michael@0: 
michael@0: #if defined(DEBUG)
michael@0: /*
michael@0:  * Disassemblers, for debugging only.
michael@0:  */
michael@0: bool
michael@0: js_Disassemble(JSContext *cx, JS::Handle<JSScript*> script, bool lines, js::Sprinter *sp);
michael@0: 
michael@0: unsigned
michael@0: js_Disassemble1(JSContext *cx, JS::Handle<JSScript*> script, jsbytecode *pc, unsigned loc,
michael@0:                 bool lines, js::Sprinter *sp);
michael@0: 
michael@0: #endif
michael@0: 
michael@0: void
michael@0: js_DumpPCCounts(JSContext *cx, JS::Handle<JSScript*> script, js::Sprinter *sp);
michael@0: 
michael@0: #ifdef JS_ION
michael@0: namespace js {
michael@0: namespace jit { struct IonScriptCounts; }
michael@0: void
michael@0: DumpIonScriptCounts(js::Sprinter *sp, jit::IonScriptCounts *ionCounts);
michael@0: }
michael@0: #endif
michael@0: 
michael@0: #endif /* jsopcode_h */