freeswitch/libs/js/src/jsemit.h

593 lines
27 KiB
C

/* -*- 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 jsemit_h___
#define jsemit_h___
/*
* JS bytecode generation.
*/
#include "jsstddef.h"
#include "jstypes.h"
#include "jsatom.h"
#include "jsopcode.h"
#include "jsprvtd.h"
#include "jspubtd.h"
JS_BEGIN_EXTERN_C
/*
* NB: If you add non-loop STMT_* enumerators, do so before STMT_DO_LOOP or
* you will break the STMT_IS_LOOP macro, just below this enum.
*/
typedef enum JSStmtType {
STMT_BLOCK = 0, /* compound statement: { s1[;... sN] } */
STMT_LABEL = 1, /* labeled statement: L: s */
STMT_IF = 2, /* if (then) statement */
STMT_ELSE = 3, /* else clause of if statement */
STMT_SWITCH = 4, /* switch statement */
STMT_WITH = 5, /* with statement */
STMT_TRY = 6, /* try statement */
STMT_CATCH = 7, /* catch block */
STMT_FINALLY = 8, /* finally statement */
STMT_SUBROUTINE = 9, /* gosub-target subroutine body */
STMT_DO_LOOP = 10, /* do/while loop statement */
STMT_FOR_LOOP = 11, /* for loop statement */
STMT_FOR_IN_LOOP = 12, /* for/in loop statement */
STMT_WHILE_LOOP = 13 /* while loop statement */
} JSStmtType;
#define STMT_IS_LOOP(stmt) ((stmt)->type >= STMT_DO_LOOP)
typedef struct JSStmtInfo JSStmtInfo;
struct JSStmtInfo {
JSStmtType type; /* statement type */
ptrdiff_t update; /* loop update offset (top if none) */
ptrdiff_t breaks; /* offset of last break in loop */
ptrdiff_t continues; /* offset of last continue in loop */
ptrdiff_t gosub; /* offset of last GOSUB for this finally */
ptrdiff_t catchJump; /* offset of last end-of-catch jump */
JSAtom *label; /* name of LABEL or CATCH var */
JSStmtInfo *down; /* info for enclosing statement */
};
#define SET_STATEMENT_TOP(stmt, top) \
((stmt)->update = (top), (stmt)->breaks = \
(stmt)->continues = (stmt)->catchJump = (stmt)->gosub = (-1))
struct JSTreeContext { /* tree context for semantic checks */
uint16 flags; /* statement state flags, see below */
uint16 numGlobalVars; /* max. no. of global variables/regexps */
uint32 tryCount; /* total count of try statements parsed */
uint32 globalUses; /* optimizable global var uses in total */
uint32 loopyGlobalUses;/* optimizable global var uses in loops */
JSStmtInfo *topStmt; /* top of statement info stack */
JSAtomList decls; /* function, const, and var declarations */
JSParseNode *nodeList; /* list of recyclable parse-node structs */
};
#define TCF_COMPILING 0x01 /* generating bytecode; this tc is a cg */
#define TCF_IN_FUNCTION 0x02 /* parsing inside function body */
#define TCF_RETURN_EXPR 0x04 /* function has 'return expr;' */
#define TCF_RETURN_VOID 0x08 /* function has 'return;' */
#define TCF_IN_FOR_INIT 0x10 /* parsing init expr of for; exclude 'in' */
#define TCF_FUN_CLOSURE_VS_VAR 0x20 /* function and var with same name */
#define TCF_FUN_USES_NONLOCALS 0x40 /* function refers to non-local names */
#define TCF_FUN_HEAVYWEIGHT 0x80 /* function needs Call object per call */
#define TCF_FUN_FLAGS 0xE0 /* flags to propagate from FunctionBody */
#define TCF_HAS_DEFXMLNS 0x100 /* default xml namespace = ...; parsed */
#define TREE_CONTEXT_INIT(tc) \
((tc)->flags = (tc)->numGlobalVars = 0, \
(tc)->tryCount = (tc)->globalUses = (tc)->loopyGlobalUses = 0, \
(tc)->topStmt = NULL, ATOM_LIST_INIT(&(tc)->decls), \
(tc)->nodeList = NULL)
#define TREE_CONTEXT_FINISH(tc) \
((void)0)
/*
* Span-dependent instructions are jumps whose span (from the jump bytecode to
* the jump target) may require 2 or 4 bytes of immediate operand.
*/
typedef struct JSSpanDep JSSpanDep;
typedef struct JSJumpTarget JSJumpTarget;
struct JSSpanDep {
ptrdiff_t top; /* offset of first bytecode in an opcode */
ptrdiff_t offset; /* offset - 1 within opcode of jump operand */
ptrdiff_t before; /* original offset - 1 of jump operand */
JSJumpTarget *target; /* tagged target pointer or backpatch delta */
};
/*
* Jump targets are stored in an AVL tree, for O(log(n)) lookup with targets
* sorted by offset from left to right, so that targets after a span-dependent
* instruction whose jump offset operand must be extended can be found quickly
* and adjusted upward (toward higher offsets).
*/
struct JSJumpTarget {
ptrdiff_t offset; /* offset of span-dependent jump target */
int balance; /* AVL tree balance number */
JSJumpTarget *kids[2]; /* left and right AVL tree child pointers */
};
#define JT_LEFT 0
#define JT_RIGHT 1
#define JT_OTHER_DIR(dir) (1 - (dir))
#define JT_IMBALANCE(dir) (((dir) << 1) - 1)
#define JT_DIR(imbalance) (((imbalance) + 1) >> 1)
/*
* Backpatch deltas are encoded in JSSpanDep.target if JT_TAG_BIT is clear,
* so we can maintain backpatch chains when using span dependency records to
* hold jump offsets that overflow 16 bits.
*/
#define JT_TAG_BIT ((jsword) 1)
#define JT_UNTAG_SHIFT 1
#define JT_SET_TAG(jt) ((JSJumpTarget *)((jsword)(jt) | JT_TAG_BIT))
#define JT_CLR_TAG(jt) ((JSJumpTarget *)((jsword)(jt) & ~JT_TAG_BIT))
#define JT_HAS_TAG(jt) ((jsword)(jt) & JT_TAG_BIT)
#define BITS_PER_PTRDIFF (sizeof(ptrdiff_t) * JS_BITS_PER_BYTE)
#define BITS_PER_BPDELTA (BITS_PER_PTRDIFF - 1 - JT_UNTAG_SHIFT)
#define BPDELTA_MAX (((ptrdiff_t)1 << BITS_PER_BPDELTA) - 1)
#define BPDELTA_TO_JT(bp) ((JSJumpTarget *)((bp) << JT_UNTAG_SHIFT))
#define JT_TO_BPDELTA(jt) ((ptrdiff_t)((jsword)(jt) >> JT_UNTAG_SHIFT))
#define SD_SET_TARGET(sd,jt) ((sd)->target = JT_SET_TAG(jt))
#define SD_GET_TARGET(sd) (JS_ASSERT(JT_HAS_TAG((sd)->target)), \
JT_CLR_TAG((sd)->target))
#define SD_SET_BPDELTA(sd,bp) ((sd)->target = BPDELTA_TO_JT(bp))
#define SD_GET_BPDELTA(sd) (JS_ASSERT(!JT_HAS_TAG((sd)->target)), \
JT_TO_BPDELTA((sd)->target))
/* Avoid asserting twice by expanding SD_GET_TARGET in the "then" clause. */
#define SD_SPAN(sd,pivot) (SD_GET_TARGET(sd) \
? JT_CLR_TAG((sd)->target)->offset - (pivot) \
: 0)
struct JSCodeGenerator {
JSTreeContext treeContext; /* base state: statement info stack, etc. */
JSArenaPool *codePool; /* pointer to thread code arena pool */
JSArenaPool *notePool; /* pointer to thread srcnote arena pool */
void *codeMark; /* low watermark in cg->codePool */
void *noteMark; /* low watermark in cg->notePool */
void *tempMark; /* low watermark in cx->tempPool */
struct {
jsbytecode *base; /* base of JS bytecode vector */
jsbytecode *limit; /* one byte beyond end of bytecode */
jsbytecode *next; /* pointer to next free bytecode */
jssrcnote *notes; /* source notes, see below */
uintN noteCount; /* number of source notes so far */
uintN noteMask; /* growth increment for notes */
ptrdiff_t lastNoteOffset; /* code offset for last source note */
uintN currentLine; /* line number for tree-based srcnote gen */
} prolog, main, *current;
const char *filename; /* null or weak link to source filename */
uintN firstLine; /* first line, for js_NewScriptFromCG */
JSPrincipals *principals; /* principals for constant folding eval */
JSAtomList atomList; /* literals indexed for mapping */
intN stackDepth; /* current stack depth in script frame */
uintN maxStackDepth; /* maximum stack depth so far */
JSTryNote *tryBase; /* first exception handling note */
JSTryNote *tryNext; /* next available note */
size_t tryNoteSpace; /* # of bytes allocated at tryBase */
JSSpanDep *spanDeps; /* span dependent instruction records */
JSJumpTarget *jumpTargets; /* AVL tree of jump target offsets */
JSJumpTarget *jtFreeList; /* JT_LEFT-linked list of free structs */
uintN numSpanDeps; /* number of span dependencies */
uintN numJumpTargets; /* number of jump targets */
ptrdiff_t spanDepTodo; /* offset from main.base of potentially
unoptimized spandeps */
uintN emitLevel; /* js_EmitTree recursion level */
JSAtomList constList; /* compile time constants */
JSCodeGenerator *parent; /* Enclosing function or global context */
};
#define CG_BASE(cg) ((cg)->current->base)
#define CG_LIMIT(cg) ((cg)->current->limit)
#define CG_NEXT(cg) ((cg)->current->next)
#define CG_CODE(cg,offset) (CG_BASE(cg) + (offset))
#define CG_OFFSET(cg) PTRDIFF(CG_NEXT(cg), CG_BASE(cg), jsbytecode)
#define CG_NOTES(cg) ((cg)->current->notes)
#define CG_NOTE_COUNT(cg) ((cg)->current->noteCount)
#define CG_NOTE_MASK(cg) ((cg)->current->noteMask)
#define CG_LAST_NOTE_OFFSET(cg) ((cg)->current->lastNoteOffset)
#define CG_CURRENT_LINE(cg) ((cg)->current->currentLine)
#define CG_PROLOG_BASE(cg) ((cg)->prolog.base)
#define CG_PROLOG_LIMIT(cg) ((cg)->prolog.limit)
#define CG_PROLOG_NEXT(cg) ((cg)->prolog.next)
#define CG_PROLOG_CODE(cg,poff) (CG_PROLOG_BASE(cg) + (poff))
#define CG_PROLOG_OFFSET(cg) PTRDIFF(CG_PROLOG_NEXT(cg), CG_PROLOG_BASE(cg),\
jsbytecode)
#define CG_SWITCH_TO_MAIN(cg) ((cg)->current = &(cg)->main)
#define CG_SWITCH_TO_PROLOG(cg) ((cg)->current = &(cg)->prolog)
/*
* Initialize cg to allocate bytecode space from codePool, source note space
* from notePool, and all other arena-allocated temporaries from cx->tempPool.
* Return true on success. Report an error and return false if the initial
* code segment can't be allocated.
*/
extern JS_FRIEND_API(JSBool)
js_InitCodeGenerator(JSContext *cx, JSCodeGenerator *cg,
JSArenaPool *codePool, JSArenaPool *notePool,
const char *filename, uintN lineno,
JSPrincipals *principals);
/*
* Release cg->codePool, cg->notePool, and cx->tempPool to marks set by
* js_InitCodeGenerator. Note that cgs are magic: they own the arena pool
* "tops-of-stack" space above their codeMark, noteMark, and tempMark points.
* This means you cannot alloc from tempPool and save the pointer beyond the
* next JS_FinishCodeGenerator.
*/
extern JS_FRIEND_API(void)
js_FinishCodeGenerator(JSContext *cx, JSCodeGenerator *cg);
/*
* Emit one bytecode.
*/
extern ptrdiff_t
js_Emit1(JSContext *cx, JSCodeGenerator *cg, JSOp op);
/*
* Emit two bytecodes, an opcode (op) with a byte of immediate operand (op1).
*/
extern ptrdiff_t
js_Emit2(JSContext *cx, JSCodeGenerator *cg, JSOp op, jsbytecode op1);
/*
* Emit three bytecodes, an opcode with two bytes of immediate operands.
*/
extern ptrdiff_t
js_Emit3(JSContext *cx, JSCodeGenerator *cg, JSOp op, jsbytecode op1,
jsbytecode op2);
/*
* Emit (1 + extra) bytecodes, for N bytes of op and its immediate operand.
*/
extern ptrdiff_t
js_EmitN(JSContext *cx, JSCodeGenerator *cg, JSOp op, size_t extra);
/*
* Unsafe macro to call js_SetJumpOffset and return false if it does.
*/
#define CHECK_AND_SET_JUMP_OFFSET(cx,cg,pc,off) \
JS_BEGIN_MACRO \
if (!js_SetJumpOffset(cx, cg, pc, off)) \
return JS_FALSE; \
JS_END_MACRO
#define CHECK_AND_SET_JUMP_OFFSET_AT(cx,cg,off) \
CHECK_AND_SET_JUMP_OFFSET(cx, cg, CG_CODE(cg,off), CG_OFFSET(cg) - (off))
extern JSBool
js_SetJumpOffset(JSContext *cx, JSCodeGenerator *cg, jsbytecode *pc,
ptrdiff_t off);
/* Test whether we're in a with statement. */
extern JSBool
js_InWithStatement(JSTreeContext *tc);
/* Test whether we're in a catch block with exception named by atom. */
extern JSBool
js_InCatchBlock(JSTreeContext *tc, JSAtom *atom);
/*
* Push the C-stack-allocated struct at stmt onto the stmtInfo stack.
*/
extern void
js_PushStatement(JSTreeContext *tc, JSStmtInfo *stmt, JSStmtType type,
ptrdiff_t top);
/*
* Pop tc->topStmt. If the top JSStmtInfo struct is not stack-allocated, it
* is up to the caller to free it.
*/
extern void
js_PopStatement(JSTreeContext *tc);
/*
* Like js_PopStatement(&cg->treeContext), also patch breaks and continues.
* May fail if a jump offset overflows.
*/
extern JSBool
js_PopStatementCG(JSContext *cx, JSCodeGenerator *cg);
/*
* Define and lookup a primitive jsval associated with the const named by atom.
* js_DefineCompileTimeConstant analyzes the constant-folded initializer at pn
* and saves the const's value in cg->constList, if it can be used at compile
* time. It returns true unless an error occurred.
*
* If the initializer's value could not be saved, js_LookupCompileTimeConstant
* calls will return the undefined value. js_LookupCompileTimeConstant tries
* to find a const value memorized for atom, returning true with *vp set to a
* value other than undefined if the constant was found, true with *vp set to
* JSVAL_VOID if not found, and false on error.
*/
extern JSBool
js_DefineCompileTimeConstant(JSContext *cx, JSCodeGenerator *cg, JSAtom *atom,
JSParseNode *pn);
extern JSBool
js_LookupCompileTimeConstant(JSContext *cx, JSCodeGenerator *cg, JSAtom *atom,
jsval *vp);
/*
* Emit code into cg for the tree rooted at pn.
*/
extern JSBool
js_EmitTree(JSContext *cx, JSCodeGenerator *cg, JSParseNode *pn);
/*
* Emit code into cg for the tree rooted at body, then create a persistent
* script for fun from cg.
*/
extern JSBool
js_EmitFunctionBody(JSContext *cx, JSCodeGenerator *cg, JSParseNode *body,
JSFunction *fun);
/*
* Source notes generated along with bytecode for decompiling and debugging.
* A source note is a uint8 with 5 bits of type and 3 of offset from the pc of
* the previous note. If 3 bits of offset aren't enough, extended delta notes
* (SRC_XDELTA) consisting of 2 set high order bits followed by 6 offset bits
* are emitted before the next note. Some notes have operand offsets encoded
* immediately after them, in note bytes or byte-triples.
*
* Source Note Extended Delta
* +7-6-5-4-3+2-1-0+ +7-6-5+4-3-2-1-0+
* |note-type|delta| |1 1| ext-delta |
* +---------+-----+ +---+-----------+
*
* At most one "gettable" note (i.e., a note of type other than SRC_NEWLINE,
* SRC_SETLINE, and SRC_XDELTA) applies to a given bytecode.
*
* NB: the js_SrcNoteSpec array in jsemit.c is indexed by this enum, so its
* initializers need to match the order here.
*/
typedef enum JSSrcNoteType {
SRC_NULL = 0, /* terminates a note vector */
SRC_IF = 1, /* JSOP_IFEQ bytecode is from an if-then */
SRC_IF_ELSE = 2, /* JSOP_IFEQ bytecode is from an if-then-else */
SRC_WHILE = 3, /* JSOP_IFEQ is from a while loop */
SRC_FOR = 4, /* JSOP_NOP or JSOP_POP in for loop head */
SRC_CONTINUE = 5, /* JSOP_GOTO is a continue, not a break;
also used on JSOP_ENDINIT if extra comma
at end of array literal: [1,2,,] */
SRC_VAR = 6, /* JSOP_NAME/SETNAME/FORNAME in a var decl */
SRC_PCDELTA = 7, /* distance from comma-operator to next POP,
or from CONDSWITCH to first CASE opcode --
or SRC_PCBASE variant for obj.function::foo
gets and sets */
SRC_ASSIGNOP = 8, /* += or another assign-op follows */
SRC_COND = 9, /* JSOP_IFEQ is from conditional ?: operator */
SRC_RESERVED0 = 10, /* reserved for future use */
SRC_HIDDEN = 11, /* opcode shouldn't be decompiled */
SRC_PCBASE = 12, /* distance back from annotated get- or setprop
op to first obj.prop.subprop bytecode */
SRC_LABEL = 13, /* JSOP_NOP for label: with atomid immediate */
SRC_LABELBRACE = 14, /* JSOP_NOP for label: {...} begin brace */
SRC_ENDBRACE = 15, /* JSOP_NOP for label: {...} end brace */
SRC_BREAK2LABEL = 16, /* JSOP_GOTO for 'break label' with atomid */
SRC_CONT2LABEL = 17, /* JSOP_GOTO for 'continue label' with atomid */
SRC_SWITCH = 18, /* JSOP_*SWITCH with offset to end of switch,
2nd off to first JSOP_CASE if condswitch */
SRC_FUNCDEF = 19, /* JSOP_NOP for function f() with atomid */
SRC_CATCH = 20, /* catch block has guard */
SRC_CONST = 21, /* JSOP_SETCONST in a const decl */
SRC_NEWLINE = 22, /* bytecode follows a source newline */
SRC_SETLINE = 23, /* a file-absolute source line number note */
SRC_XDELTA = 24 /* 24-31 are for extended delta notes */
} JSSrcNoteType;
#define SN_TYPE_BITS 5
#define SN_DELTA_BITS 3
#define SN_XDELTA_BITS 6
#define SN_TYPE_MASK (JS_BITMASK(SN_TYPE_BITS) << SN_DELTA_BITS)
#define SN_DELTA_MASK ((ptrdiff_t)JS_BITMASK(SN_DELTA_BITS))
#define SN_XDELTA_MASK ((ptrdiff_t)JS_BITMASK(SN_XDELTA_BITS))
#define SN_MAKE_NOTE(sn,t,d) (*(sn) = (jssrcnote) \
(((t) << SN_DELTA_BITS) \
| ((d) & SN_DELTA_MASK)))
#define SN_MAKE_XDELTA(sn,d) (*(sn) = (jssrcnote) \
((SRC_XDELTA << SN_DELTA_BITS) \
| ((d) & SN_XDELTA_MASK)))
#define SN_IS_XDELTA(sn) ((*(sn) >> SN_DELTA_BITS) >= SRC_XDELTA)
#define SN_TYPE(sn) (SN_IS_XDELTA(sn) ? SRC_XDELTA \
: *(sn) >> SN_DELTA_BITS)
#define SN_SET_TYPE(sn,type) SN_MAKE_NOTE(sn, type, SN_DELTA(sn))
#define SN_IS_GETTABLE(sn) (SN_TYPE(sn) < SRC_NEWLINE)
#define SN_DELTA(sn) ((ptrdiff_t)(SN_IS_XDELTA(sn) \
? *(sn) & SN_XDELTA_MASK \
: *(sn) & SN_DELTA_MASK))
#define SN_SET_DELTA(sn,delta) (SN_IS_XDELTA(sn) \
? SN_MAKE_XDELTA(sn, delta) \
: SN_MAKE_NOTE(sn, SN_TYPE(sn), delta))
#define SN_DELTA_LIMIT ((ptrdiff_t)JS_BIT(SN_DELTA_BITS))
#define SN_XDELTA_LIMIT ((ptrdiff_t)JS_BIT(SN_XDELTA_BITS))
/*
* Offset fields follow certain notes and are frequency-encoded: an offset in
* [0,0x7f] consumes one byte, an offset in [0x80,0x7fffff] takes three, and
* the high bit of the first byte is set.
*/
#define SN_3BYTE_OFFSET_FLAG 0x80
#define SN_3BYTE_OFFSET_MASK 0x7f
typedef struct JSSrcNoteSpec {
const char *name; /* name for disassembly/debugging output */
uint8 arity; /* number of offset operands */
uint8 offsetBias; /* bias of offset(s) from annotated pc */
int8 isSpanDep; /* 1 or -1 if offsets could span extended ops,
0 otherwise; sign tells span direction */
} JSSrcNoteSpec;
extern JS_FRIEND_DATA(JSSrcNoteSpec) js_SrcNoteSpec[];
extern JS_FRIEND_API(uintN) js_SrcNoteLength(jssrcnote *sn);
#define SN_LENGTH(sn) ((js_SrcNoteSpec[SN_TYPE(sn)].arity == 0) ? 1 \
: js_SrcNoteLength(sn))
#define SN_NEXT(sn) ((sn) + SN_LENGTH(sn))
/* A source note array is terminated by an all-zero element. */
#define SN_MAKE_TERMINATOR(sn) (*(sn) = SRC_NULL)
#define SN_IS_TERMINATOR(sn) (*(sn) == SRC_NULL)
/*
* Append a new source note of the given type (and therefore size) to cg's
* notes dynamic array, updating cg->noteCount. Return the new note's index
* within the array pointed at by cg->current->notes. Return -1 if out of
* memory.
*/
extern intN
js_NewSrcNote(JSContext *cx, JSCodeGenerator *cg, JSSrcNoteType type);
extern intN
js_NewSrcNote2(JSContext *cx, JSCodeGenerator *cg, JSSrcNoteType type,
ptrdiff_t offset);
extern intN
js_NewSrcNote3(JSContext *cx, JSCodeGenerator *cg, JSSrcNoteType type,
ptrdiff_t offset1, ptrdiff_t offset2);
/*
* NB: this function can add at most one extra extended delta note.
*/
extern jssrcnote *
js_AddToSrcNoteDelta(JSContext *cx, JSCodeGenerator *cg, jssrcnote *sn,
ptrdiff_t delta);
/*
* Get and set the offset operand identified by which (0 for the first, etc.).
*/
extern JS_FRIEND_API(ptrdiff_t)
js_GetSrcNoteOffset(jssrcnote *sn, uintN which);
extern JSBool
js_SetSrcNoteOffset(JSContext *cx, JSCodeGenerator *cg, uintN index,
uintN which, ptrdiff_t offset);
/*
* Finish taking source notes in cx's notePool, copying final notes to the new
* stable store allocated by the caller and passed in via notes. Return false
* on malloc failure, which means this function reported an error.
*
* To compute the number of jssrcnotes to allocate and pass in via notes, use
* the CG_COUNT_FINAL_SRCNOTES macro. This macro knows a lot about details of
* js_FinishTakingSrcNotes, SO DON'T CHANGE jsemit.c's js_FinishTakingSrcNotes
* FUNCTION WITHOUT CHECKING WHETHER THIS MACRO NEEDS CORRESPONDING CHANGES!
*/
#define CG_COUNT_FINAL_SRCNOTES(cg, cnt) \
JS_BEGIN_MACRO \
ptrdiff_t diff_ = CG_PROLOG_OFFSET(cg) - (cg)->prolog.lastNoteOffset; \
cnt = (cg)->prolog.noteCount + (cg)->main.noteCount + 1; \
if ((cg)->prolog.noteCount && \
(cg)->prolog.currentLine != (cg)->firstLine) { \
if (diff_ > SN_DELTA_MASK) \
cnt += JS_HOWMANY(diff_ - SN_DELTA_MASK, SN_XDELTA_MASK); \
cnt += 2 + (((cg)->firstLine > SN_3BYTE_OFFSET_MASK) << 1); \
} else if (diff_ > 0) { \
if (cg->main.noteCount) { \
jssrcnote *sn_ = (cg)->main.notes; \
diff_ -= SN_IS_XDELTA(sn_) \
? SN_XDELTA_MASK - (*sn_ & SN_XDELTA_MASK) \
: SN_DELTA_MASK - (*sn_ & SN_DELTA_MASK); \
} \
if (diff_ > 0) \
cnt += JS_HOWMANY(diff_, SN_XDELTA_MASK); \
} \
JS_END_MACRO
extern JSBool
js_FinishTakingSrcNotes(JSContext *cx, JSCodeGenerator *cg, jssrcnote *notes);
/*
* Allocate cg->treeContext.tryCount notes (plus one for the end sentinel)
* from cx->tempPool and set up cg->tryBase/tryNext for exactly tryCount
* js_NewTryNote calls. The storage is freed by js_FinishCodeGenerator.
*/
extern JSBool
js_AllocTryNotes(JSContext *cx, JSCodeGenerator *cg);
/*
* Grab the next trynote slot in cg, filling it in appropriately.
*/
extern JSTryNote *
js_NewTryNote(JSContext *cx, JSCodeGenerator *cg, ptrdiff_t start,
ptrdiff_t end, ptrdiff_t catchStart);
/*
* Finish generating exception information into the space at notes. As with
* js_FinishTakingSrcNotes, the caller must use CG_COUNT_FINAL_TRYNOTES(cg) to
* preallocate enough space in a JSTryNote[] to pass as the notes parameter of
* js_FinishTakingTryNotes.
*/
#define CG_COUNT_FINAL_TRYNOTES(cg, cnt) \
JS_BEGIN_MACRO \
cnt = ((cg)->tryNext > (cg)->tryBase) \
? PTRDIFF(cg->tryNext, cg->tryBase, JSTryNote) + 1 \
: 0; \
JS_END_MACRO
extern void
js_FinishTakingTryNotes(JSContext *cx, JSCodeGenerator *cg, JSTryNote *notes);
JS_END_EXTERN_C
#endif /* jsemit_h___ */