/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- * * ***** BEGIN LICENSE BLOCK ***** * Version: MPL 1.1/GPL 2.0/LGPL 2.1 * * The contents of this file are subject to the Mozilla Public License Version * 1.1 (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * http://www.mozilla.org/MPL/ * * Software distributed under the License is distributed on an "AS IS" basis, * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License * for the specific language governing rights and limitations under the * License. * * The Original Code is Mozilla Communicator client code, released * March 31, 1998. * * The Initial Developer of the Original Code is * Netscape Communications Corporation. * Portions created by the Initial Developer are Copyright (C) 1998 * the Initial Developer. All Rights Reserved. * * Contributor(s): * * Alternatively, the contents of this file may be used under the terms of * either of the GNU General Public License Version 2 or later (the "GPL"), * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"), * in which case the provisions of the GPL or the LGPL are applicable instead * of those above. If you wish to allow use of your version of this file only * under the terms of either the GPL or the LGPL, and not to allow others to * use your version of this file under the terms of the MPL, indicate your * decision by deleting the provisions above and replace them with the notice * and other provisions required by the GPL or the LGPL. If you do not delete * the provisions above, a recipient may use your version of this file under * the terms of any one of the MPL, the GPL or the LGPL. * * ***** END LICENSE BLOCK ***** */ #ifndef jsopcode_h___ #define jsopcode_h___ /* * JS bytecode definitions. */ #include #include "jsprvtd.h" #include "jspubtd.h" #include "jsutil.h" #include "jsarena.h" #ifdef __cplusplus # include "jsvalue.h" #endif JS_BEGIN_EXTERN_C /* * JS operation bytecodes. */ typedef enum JSOp { #define OPDEF(op,val,name,token,length,nuses,ndefs,prec,format) \ op = val, #include "jsopcode.tbl" #undef OPDEF JSOP_LIMIT, /* * These pseudo-ops help js_DecompileValueGenerator decompile JSOP_SETNAME, * JSOP_SETPROP, and JSOP_SETELEM, respectively. They are never stored in * bytecode, so they don't preempt valid opcodes. */ JSOP_GETPROP2 = JSOP_LIMIT, JSOP_GETELEM2 = JSOP_LIMIT + 1, JSOP_FAKE_LIMIT = JSOP_GETELEM2 } JSOp; /* * JS bytecode formats. */ #define JOF_BYTE 0 /* single bytecode, no immediates */ #define JOF_JUMP 1 /* signed 16-bit jump offset immediate */ #define JOF_ATOM 2 /* unsigned 16-bit constant index */ #define JOF_UINT16 3 /* unsigned 16-bit immediate operand */ #define JOF_TABLESWITCH 4 /* table switch */ #define JOF_LOOKUPSWITCH 5 /* lookup switch */ #define JOF_QARG 6 /* quickened get/set function argument ops */ #define JOF_LOCAL 7 /* var or block-local variable */ #define JOF_SLOTATOM 8 /* uint16 slot + constant index */ #define JOF_JUMPX 9 /* signed 32-bit jump offset immediate */ #define JOF_TABLESWITCHX 10 /* extended (32-bit offset) table switch */ #define JOF_LOOKUPSWITCHX 11 /* extended (32-bit offset) lookup switch */ #define JOF_UINT24 12 /* extended unsigned 24-bit literal (index) */ #define JOF_UINT8 13 /* uint8 immediate, e.g. top 8 bits of 24-bit atom index */ #define JOF_INT32 14 /* int32 immediate operand */ #define JOF_OBJECT 15 /* unsigned 16-bit object index */ #define JOF_SLOTOBJECT 16 /* uint16 slot index + object index */ #define JOF_REGEXP 17 /* unsigned 16-bit regexp index */ #define JOF_INT8 18 /* int8 immediate operand */ #define JOF_ATOMOBJECT 19 /* uint16 constant index + object index */ #define JOF_UINT16PAIR 20 /* pair of uint16 immediates */ #define JOF_GLOBAL 21 /* uint16 global array index */ #define JOF_TYPEMASK 0x001f /* mask for above immediate types */ #define JOF_NAME (1U<<5) /* name operation */ #define JOF_PROP (2U<<5) /* obj.prop operation */ #define JOF_ELEM (3U<<5) /* obj[index] operation */ #define JOF_XMLNAME (4U<<5) /* XML name: *, a::b, @a, @a::b, etc. */ #define JOF_VARPROP (5U<<5) /* x.prop for this, arg, var, or local x */ #define JOF_MODEMASK (7U<<5) /* mask for above addressing modes */ #define JOF_SET (1U<<8) /* set (i.e., assignment) operation */ #define JOF_DEL (1U<<9) /* delete operation */ #define JOF_DEC (1U<<10) /* decrement (--, not ++) opcode */ #define JOF_INC (2U<<10) /* increment (++, not --) opcode */ #define JOF_INCDEC (3U<<10) /* increment or decrement opcode */ #define JOF_POST (1U<<12) /* postorder increment or decrement */ #define JOF_FOR (1U<<13) /* for-in property op (akin to JOF_SET) */ #define JOF_ASSIGNING JOF_SET /* hint for Class.resolve, used for ops that do simplex assignment */ #define JOF_DETECTING (1U<<14) /* object detection for JSNewResolveOp */ #define JOF_BACKPATCH (1U<<15) /* backpatch placeholder during codegen */ #define JOF_LEFTASSOC (1U<<16) /* left-associative operator */ #define JOF_DECLARING (1U<<17) /* var, const, or function declaration op */ #define JOF_INDEXBASE (1U<<18) /* atom segment base setting prefix op */ #define JOF_CALLOP (1U<<19) /* call operation that pushes function and this */ #define JOF_PARENHEAD (1U<<20) /* opcode consumes value of expression in parenthesized statement head */ #define JOF_INVOKE (1U<<21) /* JSOP_CALL, JSOP_NEW, JSOP_EVAL */ #define JOF_TMPSLOT (1U<<22) /* interpreter uses extra temporary slot to root intermediate objects besides the slots opcode uses */ #define JOF_TMPSLOT2 (2U<<22) /* interpreter uses extra 2 temporary slot besides the slots opcode uses */ #define JOF_TMPSLOT3 (3U<<22) /* interpreter uses extra 3 temporary slot besides the slots opcode uses */ #define JOF_TMPSLOT_SHIFT 22 #define JOF_TMPSLOT_MASK (JS_BITMASK(2) << JOF_TMPSLOT_SHIFT) #define JOF_SHARPSLOT (1U<<24) /* first immediate is uint16 stack slot no. that needs fixup when in global code (see Compiler::compileScript) */ #define JOF_GNAME (1U<<25) /* predicted global name */ /* Shorthands for type from format and type from opcode. */ #define JOF_TYPE(fmt) ((fmt) & JOF_TYPEMASK) #define JOF_OPTYPE(op) JOF_TYPE(js_CodeSpec[op].format) /* Shorthands for mode from format and mode from opcode. */ #define JOF_MODE(fmt) ((fmt) & JOF_MODEMASK) #define JOF_OPMODE(op) JOF_MODE(js_CodeSpec[op].format) #define JOF_TYPE_IS_EXTENDED_JUMP(t) \ ((unsigned)((t) - JOF_JUMPX) <= (unsigned)(JOF_LOOKUPSWITCHX - JOF_JUMPX)) /* * Immediate operand getters, setters, and bounds. */ /* Common uint16 immediate format helpers. */ #define UINT16_LEN 2 #define UINT16_HI(i) ((jsbytecode)((i) >> 8)) #define UINT16_LO(i) ((jsbytecode)(i)) #define GET_UINT16(pc) ((uintN)(((pc)[1] << 8) | (pc)[2])) #define SET_UINT16(pc,i) ((pc)[1] = UINT16_HI(i), (pc)[2] = UINT16_LO(i)) #define UINT16_LIMIT ((uintN)1 << 16) /* Short (2-byte signed offset) relative jump macros. */ #define JUMP_OFFSET_LEN 2 #define JUMP_OFFSET_HI(off) ((jsbytecode)((off) >> 8)) #define JUMP_OFFSET_LO(off) ((jsbytecode)(off)) #define GET_JUMP_OFFSET(pc) ((int16)GET_UINT16(pc)) #define SET_JUMP_OFFSET(pc,off) ((pc)[1] = JUMP_OFFSET_HI(off), \ (pc)[2] = JUMP_OFFSET_LO(off)) #define JUMP_OFFSET_MIN ((int16)0x8000) #define JUMP_OFFSET_MAX ((int16)0x7fff) /* * When a short jump won't hold a relative offset, its 2-byte immediate offset * operand is an unsigned index of a span-dependency record, maintained until * code generation finishes -- after which some (but we hope not nearly all) * span-dependent jumps must be extended (see OptimizeSpanDeps in jsemit.c). * * If the span-dependency record index overflows SPANDEP_INDEX_MAX, the jump * offset will contain SPANDEP_INDEX_HUGE, indicating that the record must be * found (via binary search) by its "before span-dependency optimization" pc * offset (from script main entry point). */ #define GET_SPANDEP_INDEX(pc) ((uint16)GET_UINT16(pc)) #define SET_SPANDEP_INDEX(pc,i) ((pc)[1] = JUMP_OFFSET_HI(i), \ (pc)[2] = JUMP_OFFSET_LO(i)) #define SPANDEP_INDEX_MAX ((uint16)0xfffe) #define SPANDEP_INDEX_HUGE ((uint16)0xffff) /* Ultimately, if short jumps won't do, emit long (4-byte signed) offsets. */ #define JUMPX_OFFSET_LEN 4 #define JUMPX_OFFSET_B3(off) ((jsbytecode)((off) >> 24)) #define JUMPX_OFFSET_B2(off) ((jsbytecode)((off) >> 16)) #define JUMPX_OFFSET_B1(off) ((jsbytecode)((off) >> 8)) #define JUMPX_OFFSET_B0(off) ((jsbytecode)(off)) #define GET_JUMPX_OFFSET(pc) ((int32)(((pc)[1] << 24) | ((pc)[2] << 16) \ | ((pc)[3] << 8) | (pc)[4])) #define SET_JUMPX_OFFSET(pc,off)((pc)[1] = JUMPX_OFFSET_B3(off), \ (pc)[2] = JUMPX_OFFSET_B2(off), \ (pc)[3] = JUMPX_OFFSET_B1(off), \ (pc)[4] = JUMPX_OFFSET_B0(off)) #define JUMPX_OFFSET_MIN ((int32)0x80000000) #define JUMPX_OFFSET_MAX ((int32)0x7fffffff) /* * A literal is indexed by a per-script atom or object maps. Most scripts * have relatively few literals, so the standard JOF_ATOM, JOF_OBJECT and * JOF_REGEXP formats specifies a fixed 16 bits of immediate operand index. * A script with more than 64K literals must wrap the bytecode into * JSOP_INDEXBASE and JSOP_RESETBASE pair. */ #define INDEX_LEN 2 #define INDEX_HI(i) ((jsbytecode)((i) >> 8)) #define INDEX_LO(i) ((jsbytecode)(i)) #define GET_INDEX(pc) GET_UINT16(pc) #define SET_INDEX(pc,i) ((pc)[1] = INDEX_HI(i), (pc)[2] = INDEX_LO(i)) #define GET_INDEXBASE(pc) (JS_ASSERT(*(pc) == JSOP_INDEXBASE), \ ((uintN)((pc)[1])) << 16) #define INDEXBASE_LEN 1 #define UINT24_HI(i) ((jsbytecode)((i) >> 16)) #define UINT24_MID(i) ((jsbytecode)((i) >> 8)) #define UINT24_LO(i) ((jsbytecode)(i)) #define GET_UINT24(pc) ((jsatomid)(((pc)[1] << 16) | \ ((pc)[2] << 8) | \ (pc)[3])) #define SET_UINT24(pc,i) ((pc)[1] = UINT24_HI(i), \ (pc)[2] = UINT24_MID(i), \ (pc)[3] = UINT24_LO(i)) #define GET_INT8(pc) ((jsint)(int8)(pc)[1]) #define GET_INT32(pc) ((jsint)(((uint32)((pc)[1]) << 24) | \ ((uint32)((pc)[2]) << 16) | \ ((uint32)((pc)[3]) << 8) | \ (uint32)(pc)[4])) #define SET_INT32(pc,i) ((pc)[1] = (jsbytecode)((uint32)(i) >> 24), \ (pc)[2] = (jsbytecode)((uint32)(i) >> 16), \ (pc)[3] = (jsbytecode)((uint32)(i) >> 8), \ (pc)[4] = (jsbytecode)(uint32)(i)) /* Index limit is determined by SN_3BYTE_OFFSET_FLAG, see jsemit.h. */ #define INDEX_LIMIT_LOG2 23 #define INDEX_LIMIT ((uint32)1 << INDEX_LIMIT_LOG2) /* Actual argument count operand format helpers. */ #define ARGC_HI(argc) UINT16_HI(argc) #define ARGC_LO(argc) UINT16_LO(argc) #define GET_ARGC(pc) GET_UINT16(pc) #define ARGC_LIMIT UINT16_LIMIT /* Synonyms for quick JOF_QARG and JOF_LOCAL bytecodes. */ #define GET_ARGNO(pc) GET_UINT16(pc) #define SET_ARGNO(pc,argno) SET_UINT16(pc,argno) #define ARGNO_LEN 2 #define ARGNO_LIMIT UINT16_LIMIT #define GET_SLOTNO(pc) GET_UINT16(pc) #define SET_SLOTNO(pc,varno) SET_UINT16(pc,varno) #define SLOTNO_LEN 2 #define SLOTNO_LIMIT UINT16_LIMIT struct JSCodeSpec { int8 length; /* length including opcode byte */ int8 nuses; /* arity, -1 if variadic */ int8 ndefs; /* number of stack results */ uint8 prec; /* operator precedence */ uint32 format; /* immediate operand format */ #ifdef __cplusplus uint32 type() const { return JOF_TYPE(format); } #endif }; extern const JSCodeSpec js_CodeSpec[]; extern uintN js_NumCodeSpecs; extern const char *js_CodeName[]; extern const char js_EscapeMap[]; /* Silence unreferenced formal parameter warnings */ #ifdef _MSC_VER #pragma warning(push) #pragma warning(disable:4100) #endif /* * Return a GC'ed string containing the chars in str, with any non-printing * chars or quotes (' or " as specified by the quote argument) escaped, and * with the quote character at the beginning and end of the result string. */ extern JSString * js_QuoteString(JSContext *cx, JSString *str, jschar quote); /* * JSPrinter operations, for printf style message formatting. The return * value from js_GetPrinterOutput() is the printer's cumulative output, in * a GC'ed string. * * strict is true if the context in which the output will appear has * already been marked as strict, thus indicating that nested * functions need not be re-marked with a strict directive. It should * be false in the outermost printer. */ extern JSPrinter * js_NewPrinter(JSContext *cx, const char *name, JSFunction *fun, uintN indent, JSBool pretty, JSBool grouped, JSBool strict); extern void js_DestroyPrinter(JSPrinter *jp); extern JSString * js_GetPrinterOutput(JSPrinter *jp); extern int js_printf(JSPrinter *jp, const char *format, ...); extern JSBool js_puts(JSPrinter *jp, const char *s); /* * Get index operand from the bytecode using a bytecode analysis to deduce the * the index register. This function is infallible, in spite of taking cx as * its first parameter; it uses only cx->runtime when calling JS_GetTrapOpcode. * The GET_*_FROM_BYTECODE macros that call it pick up cx from their caller's * lexical environments. */ uintN js_GetIndexFromBytecode(JSContext *cx, JSScript *script, jsbytecode *pc, ptrdiff_t pcoff); /* * A slower version of GET_ATOM when the caller does not want to maintain * the index segment register itself. */ #define GET_ATOM_FROM_BYTECODE(script, pc, pcoff, atom) \ JS_BEGIN_MACRO \ JS_ASSERT(*(pc) != JSOP_DOUBLE); \ uintN index_ = js_GetIndexFromBytecode(cx, (script), (pc), (pcoff)); \ JS_GET_SCRIPT_ATOM(script, pc, index_, atom); \ JS_END_MACRO /* * Variant for getting a double atom when we might be in an imacro. Bytecodes * with literals that are only ever doubles must use this macro, and never use * GET_ATOM_FROM_BYTECODE or JS_GET_SCRIPT_ATOM. * * Unfortunately some bytecodes such as JSOP_LOOKUPSWITCH have immediates that * might be string or double atoms. Those opcodes cannot be used from imacros. * See the assertions in the JSOP_DOUBLE and JSOP_LOOKUPSWTICH* opcode cases in * jsinterp.cpp. */ #define GET_DOUBLE_FROM_BYTECODE(script, pc, pcoff, dbl) \ JS_BEGIN_MACRO \ uintN index_ = js_GetIndexFromBytecode(cx, (script), (pc), (pcoff)); \ JS_ASSERT(index_ < (script)->consts()->length); \ (dbl) = (script)->getConst(index_).toDouble(); \ JS_END_MACRO #define GET_OBJECT_FROM_BYTECODE(script, pc, pcoff, obj) \ JS_BEGIN_MACRO \ uintN index_ = js_GetIndexFromBytecode(cx, (script), (pc), (pcoff)); \ obj = (script)->getObject(index_); \ JS_END_MACRO #define GET_FUNCTION_FROM_BYTECODE(script, pc, pcoff, fun) \ JS_BEGIN_MACRO \ uintN index_ = js_GetIndexFromBytecode(cx, (script), (pc), (pcoff)); \ fun = (script)->getFunction(index_); \ JS_END_MACRO #define GET_REGEXP_FROM_BYTECODE(script, pc, pcoff, obj) \ JS_BEGIN_MACRO \ uintN index_ = js_GetIndexFromBytecode(cx, (script), (pc), (pcoff)); \ obj = (script)->getRegExp(index_); \ JS_END_MACRO /* * Get the length of variable-length bytecode like JSOP_TABLESWITCH. */ extern uintN js_GetVariableBytecodeLength(jsbytecode *pc); /* * Find the number of stack slots used by a variadic opcode such as JSOP_CALL * (for such ops, JSCodeSpec.nuses is -1). */ extern uintN js_GetVariableStackUses(JSOp op, jsbytecode *pc); /* * Find the number of stack slots defined by JSOP_ENTERBLOCK (for this op, * JSCodeSpec.ndefs is -1). */ extern uintN js_GetEnterBlockStackDefs(JSContext *cx, JSScript *script, jsbytecode *pc); #ifdef __cplusplus /* Aargh, libgjs, bug 492720. */ static JS_INLINE uintN js_GetStackUses(const JSCodeSpec *cs, JSOp op, jsbytecode *pc) { JS_ASSERT(cs == &js_CodeSpec[op]); if (cs->nuses >= 0) return cs->nuses; return js_GetVariableStackUses(op, pc); } static JS_INLINE uintN js_GetStackDefs(JSContext *cx, const JSCodeSpec *cs, JSOp op, JSScript *script, jsbytecode *pc) { JS_ASSERT(cs == &js_CodeSpec[op]); if (cs->ndefs >= 0) return cs->ndefs; /* Only JSOP_ENTERBLOCK has a variable number of stack defs. */ JS_ASSERT(op == JSOP_ENTERBLOCK); return js_GetEnterBlockStackDefs(cx, script, pc); } #endif /* * Decompilers, for script, function, and expression pretty-printing. */ extern JSBool js_DecompileScript(JSPrinter *jp, JSScript *script); extern JSBool js_DecompileFunctionBody(JSPrinter *jp); extern JSBool js_DecompileFunction(JSPrinter *jp); /* * Some C++ compilers treat the language linkage (extern "C" vs. * extern "C++") as part of function (and thus pointer-to-function) * types. The use of this typedef (defined in "C") ensures that * js_DecompileToString's definition (in "C++") gets matched up with * this declaration. */ typedef JSBool (* JSDecompilerPtr)(JSPrinter *); extern JSString * js_DecompileToString(JSContext *cx, const char *name, JSFunction *fun, uintN indent, JSBool pretty, JSBool grouped, JSBool strict, JSDecompilerPtr decompiler); /* * Find the source expression that resulted in v, and return a newly allocated * C-string containing it. Fall back on v's string conversion (fallback) if we * can't find the bytecode that generated and pushed v on the operand stack. * * Search the current stack frame if spindex is JSDVG_SEARCH_STACK. Don't * look for v on the stack if spindex is JSDVG_IGNORE_STACK. Otherwise, * spindex is the negative index of v, measured from cx->fp->sp, or from a * lower frame's sp if cx->fp is native. * * The caller must call JS_free on the result after a succsesful call. */ extern char * js_DecompileValueGenerator(JSContext *cx, intN spindex, jsval v, JSString *fallback); #define JSDVG_IGNORE_STACK 0 #define JSDVG_SEARCH_STACK 1 #ifdef __cplusplus namespace js { static inline char * DecompileValueGenerator(JSContext *cx, intN spindex, const Value &v, JSString *fallback) { return js_DecompileValueGenerator(cx, spindex, Jsvalify(v), fallback); } /* * Sprintf, but with unlimited and automatically allocated buffering. */ struct Sprinter { JSContext *context; /* context executing the decompiler */ JSArenaPool *pool; /* string allocation pool */ char *base; /* base address of buffer in pool */ size_t size; /* size of buffer allocated at base */ ptrdiff_t offset; /* offset of next free char in buffer */ }; #define INIT_SPRINTER(cx, sp, ap, off) \ ((sp)->context = cx, (sp)->pool = ap, (sp)->base = NULL, (sp)->size = 0, \ (sp)->offset = off) /* * Attempt to reserve len space in sp (including a trailing NULL byte). If the * attempt succeeds, return a pointer to the start of that space and adjust the * length of sp's contents. The caller *must* completely fill this space * (including the space for the trailing NULL byte) on success. */ extern char * SprintReserveAmount(Sprinter *sp, size_t len); extern ptrdiff_t SprintPut(Sprinter *sp, const char *s, size_t len); extern ptrdiff_t SprintCString(Sprinter *sp, const char *s); extern ptrdiff_t SprintString(Sprinter *sp, JSString *str); extern ptrdiff_t Sprint(Sprinter *sp, const char *format, ...); extern bool CallResultEscapes(jsbytecode *pc); } #endif #if defined(DEBUG) && defined(__cplusplus) /* * Disassemblers, for debugging only. */ extern JS_FRIEND_API(JSBool) js_Disassemble(JSContext *cx, JSScript *script, JSBool lines, js::Sprinter *sp); extern JS_FRIEND_API(uintN) js_Disassemble1(JSContext *cx, JSScript *script, jsbytecode *pc, uintN loc, JSBool lines, js::Sprinter *sp); #endif /* * Given bytecode address pc in script's main program code, return the operand * stack depth just before (JSOp) *pc executes. */ extern uintN js_ReconstructStackDepth(JSContext *cx, JSScript *script, jsbytecode *pc); #ifdef _MSC_VER #pragma warning(pop) #endif JS_END_EXTERN_C #endif /* jsopcode_h___ */