/js/lib/Socket.IO-node/support/expresso/deps/jscoverage/js/jsemit.h
C++ Header | 777 lines | 402 code | 98 blank | 277 comment | 17 complexity | 38bc47109b221ec5f26bd211a82181ea MD5 | raw file
Possible License(s): GPL-2.0, LGPL-2.1, MPL-2.0-no-copyleft-exception, BSD-3-Clause
- /* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
- * vim: set ts=8 sw=4 et tw=79:
- *
- * ***** 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 "jsscript.h"
- #include "jsprvtd.h"
- #include "jspubtd.h"
- JS_BEGIN_EXTERN_C
- /*
- * NB: If you add enumerators for scope statements, add them between STMT_WITH
- * and STMT_CATCH, or you will break the STMT_TYPE_IS_SCOPE macro. If you add
- * non-looping statement enumerators, add them before STMT_DO_LOOP or you will
- * break the STMT_TYPE_IS_LOOP macro.
- *
- * Also remember to keep the statementName array in jsemit.c in sync.
- */
- typedef enum JSStmtType {
- STMT_LABEL, /* labeled statement: L: s */
- STMT_IF, /* if (then) statement */
- STMT_ELSE, /* else clause of if statement */
- STMT_SEQ, /* synthetic sequence of statements */
- STMT_BLOCK, /* compound statement: { s1[;... sN] } */
- STMT_SWITCH, /* switch statement */
- STMT_WITH, /* with statement */
- STMT_CATCH, /* catch block */
- STMT_TRY, /* try block */
- STMT_FINALLY, /* finally block */
- STMT_SUBROUTINE, /* gosub-target subroutine body */
- STMT_DO_LOOP, /* do/while loop statement */
- STMT_FOR_LOOP, /* for loop statement */
- STMT_FOR_IN_LOOP, /* for/in loop statement */
- STMT_WHILE_LOOP, /* while loop statement */
- STMT_LIMIT
- } JSStmtType;
- #define STMT_TYPE_IN_RANGE(t,b,e) ((uint)((t) - (b)) <= (uintN)((e) - (b)))
- /*
- * A comment on the encoding of the JSStmtType enum and type-testing macros:
- *
- * STMT_TYPE_MAYBE_SCOPE tells whether a statement type is always, or may
- * become, a lexical scope. It therefore includes block and switch (the two
- * low-numbered "maybe" scope types) and excludes with (with has dynamic scope
- * pending the "reformed with" in ES4/JS2). It includes all try-catch-finally
- * types, which are high-numbered maybe-scope types.
- *
- * STMT_TYPE_LINKS_SCOPE tells whether a JSStmtInfo of the given type eagerly
- * links to other scoping statement info records. It excludes the two early
- * "maybe" types, block and switch, as well as the try and both finally types,
- * since try and the other trailing maybe-scope types don't need block scope
- * unless they contain let declarations.
- *
- * We treat WITH as a static scope because it prevents lexical binding from
- * continuing further up the static scope chain. With the lost "reformed with"
- * proposal for ES4, we would be able to model it statically, too.
- */
- #define STMT_TYPE_MAYBE_SCOPE(type) \
- (type != STMT_WITH && \
- STMT_TYPE_IN_RANGE(type, STMT_BLOCK, STMT_SUBROUTINE))
- #define STMT_TYPE_LINKS_SCOPE(type) \
- STMT_TYPE_IN_RANGE(type, STMT_WITH, STMT_CATCH)
- #define STMT_TYPE_IS_TRYING(type) \
- STMT_TYPE_IN_RANGE(type, STMT_TRY, STMT_SUBROUTINE)
- #define STMT_TYPE_IS_LOOP(type) ((type) >= STMT_DO_LOOP)
- #define STMT_MAYBE_SCOPE(stmt) STMT_TYPE_MAYBE_SCOPE((stmt)->type)
- #define STMT_LINKS_SCOPE(stmt) (STMT_TYPE_LINKS_SCOPE((stmt)->type) || \
- ((stmt)->flags & SIF_SCOPE))
- #define STMT_IS_TRYING(stmt) STMT_TYPE_IS_TRYING((stmt)->type)
- #define STMT_IS_LOOP(stmt) STMT_TYPE_IS_LOOP((stmt)->type)
- typedef struct JSStmtInfo JSStmtInfo;
- struct JSStmtInfo {
- uint16 type; /* statement type */
- uint16 flags; /* flags, see below */
- 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 */
- union {
- JSAtom *label; /* name of LABEL */
- JSObject *blockObj; /* block scope object */
- } u;
- JSStmtInfo *down; /* info for enclosing statement */
- JSStmtInfo *downScope; /* next enclosing lexical scope */
- };
- #define SIF_SCOPE 0x0001 /* statement has its own lexical scope */
- #define SIF_BODY_BLOCK 0x0002 /* STMT_BLOCK type is a function body */
- #define SIF_FOR_BLOCK 0x0004 /* for (let ...) induced block scope */
- /*
- * To reuse space in JSStmtInfo, rename breaks and continues for use during
- * try/catch/finally code generation and backpatching. To match most common
- * use cases, the macro argument is a struct, not a struct pointer. Only a
- * loop, switch, or label statement info record can have breaks and continues,
- * and only a for loop has an update backpatch chain, so it's safe to overlay
- * these for the "trying" JSStmtTypes.
- */
- #define CATCHNOTE(stmt) ((stmt).update)
- #define GOSUBS(stmt) ((stmt).breaks)
- #define GUARDJUMP(stmt) ((stmt).continues)
- #define AT_TOP_LEVEL(tc) \
- (!(tc)->topStmt || ((tc)->topStmt->flags & SIF_BODY_BLOCK))
- #define SET_STATEMENT_TOP(stmt, top) \
- ((stmt)->update = (top), (stmt)->breaks = (stmt)->continues = (-1))
- struct JSTreeContext { /* tree context for semantic checks */
- uint16 flags; /* statement state flags, see below */
- uint16 ngvars; /* max. no. of global variables/regexps */
- JSStmtInfo *topStmt; /* top of statement info stack */
- JSStmtInfo *topScopeStmt; /* top lexical scope statement */
- JSObject *blockChain; /* compile time block scope chain (NB: one
- deeper than the topScopeStmt/downScope
- chain when in head of let block/expr) */
- JSParseNode *blockNode; /* parse node for a lexical scope.
- XXX combine with blockChain? */
- JSAtomList decls; /* function, const, and var declarations */
- JSParseContext *parseContext;
- union {
- JSFunction *fun; /* function to store argument and variable
- names when flags & TCF_IN_FUNCTION */
- JSObject *scopeChain; /* scope chain object for the script */
- } u;
- #ifdef JS_SCOPE_DEPTH_METER
- uint16 scopeDepth; /* current lexical scope chain depth */
- uint16 maxScopeDepth; /* maximum lexical scope chain depth */
- #endif
- };
- #define TCF_IN_FUNCTION 0x01 /* parsing inside function body */
- #define TCF_RETURN_EXPR 0x02 /* function has 'return expr;' */
- #define TCF_RETURN_VOID 0x04 /* function has 'return;' */
- #define TCF_IN_FOR_INIT 0x08 /* parsing init expr of for; exclude 'in' */
- #define TCF_FUN_CLOSURE_VS_VAR 0x10 /* function and var with same name */
- #define TCF_FUN_USES_NONLOCALS 0x20 /* function refers to non-local names */
- #define TCF_FUN_HEAVYWEIGHT 0x40 /* function needs Call object per call */
- #define TCF_FUN_IS_GENERATOR 0x80 /* parsed yield statement in function */
- #define TCF_HAS_DEFXMLNS 0x100 /* default xml namespace = ...; parsed */
- #define TCF_HAS_FUNCTION_STMT 0x200 /* block contains a function statement */
- #define TCF_GENEXP_LAMBDA 0x400 /* flag lambda from generator expression */
- #define TCF_COMPILE_N_GO 0x800 /* compiler-and-go mode of script, can
- optimize name references based on scope
- chain */
- #define TCF_NO_SCRIPT_RVAL 0x1000 /* API caller does not want result value
- from global script */
- /*
- * Flags to propagate out of the blocks.
- */
- #define TCF_RETURN_FLAGS (TCF_RETURN_EXPR | TCF_RETURN_VOID)
- /*
- * Flags to propagate from FunctionBody.
- */
- #define TCF_FUN_FLAGS (TCF_FUN_IS_GENERATOR | \
- TCF_FUN_HEAVYWEIGHT | \
- TCF_FUN_USES_NONLOCALS | \
- TCF_FUN_CLOSURE_VS_VAR)
- /*
- * Flags field, not stored in JSTreeContext.flags, for passing staticDepth
- * into js_CompileScript.
- */
- #define TCF_STATIC_DEPTH_MASK 0xffff0000
- #define TCF_GET_STATIC_DEPTH(f) ((uint32)(f) >> 16)
- #define TCF_PUT_STATIC_DEPTH(d) ((uint16)(d) << 16)
- #ifdef JS_SCOPE_DEPTH_METER
- # define JS_SCOPE_DEPTH_METERING(code) ((void) (code))
- #else
- # define JS_SCOPE_DEPTH_METERING(code) ((void) 0)
- #endif
- #define TREE_CONTEXT_INIT(tc, pc) \
- ((tc)->flags = (tc)->ngvars = 0, \
- (tc)->topStmt = (tc)->topScopeStmt = NULL, \
- (tc)->blockChain = NULL, \
- ATOM_LIST_INIT(&(tc)->decls), \
- (tc)->blockNode = NULL, \
- (tc)->parseContext = (pc), \
- (tc)->u.scopeChain = NULL, \
- JS_SCOPE_DEPTH_METERING((tc)->scopeDepth = (tc)->maxScopeDepth = 0))
- /*
- * For functions TREE_CONTEXT_FINISH is called the second time to finish the
- * extra tc created during code generation. We skip stats update in such
- * cases.
- */
- #define TREE_CONTEXT_FINISH(cx, tc) \
- JS_SCOPE_DEPTH_METERING( \
- (tc)->maxScopeDepth == (uintN) -1 || \
- JS_BASIC_STATS_ACCUM(&(cx)->runtime->lexicalScopeDepthStats, \
- (tc)->maxScopeDepth))
- /*
- * 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)
- typedef struct JSTryNode JSTryNode;
- struct JSTryNode {
- JSTryNote note;
- JSTryNode *prev;
- };
- typedef struct JSEmittedObjectList {
- uint32 length; /* number of emitted so far objects */
- JSParsedObjectBox *lastPob; /* last emitted object */
- } JSEmittedObjectList;
- extern void
- FinishParsedObjects(JSEmittedObjectList *emittedList, JSObjectArray *objectMap);
- 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 */
- 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;
- JSAtomList atomList; /* literals indexed for mapping */
- uintN firstLine; /* first line, for js_NewScriptFromCG */
- intN stackDepth; /* current stack depth in script frame */
- uintN maxStackDepth; /* maximum stack depth so far */
- uintN ntrynotes; /* number of allocated so far try notes */
- JSTryNode *lastTryNode; /* the last allocated try node */
- 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 arrayCompDepth; /* stack depth of array in comprehension */
- uintN emitLevel; /* js_EmitTree recursion level */
- JSAtomList constList; /* compile time constants */
- JSEmittedObjectList objectList; /* list of emitted so far objects */
- JSEmittedObjectList regexpList; /* list of emitted so far regexp
- that will be cloned during execution */
- uintN staticDepth; /* static frame chain depth */
- JSAtomList upvarList; /* map of atoms to upvar indexes */
- JSUpvarArray upvarMap; /* indexed upvar pairs (JS_realloc'ed) */
- JSCodeGenerator *parent; /* enclosing function or global context */
- };
- #define CG_TS(cg) TS((cg)->treeContext.parseContext)
- #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.
- */
- extern JS_FRIEND_API(void)
- js_InitCodeGenerator(JSContext *cx, JSCodeGenerator *cg, JSParseContext *pc,
- JSArenaPool *codePool, JSArenaPool *notePool,
- uintN lineno);
- /*
- * 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_CUSTOM(cx,cg,pc,off,BAD_EXIT) \
- JS_BEGIN_MACRO \
- if (!js_SetJumpOffset(cx, cg, pc, off)) { \
- BAD_EXIT; \
- } \
- JS_END_MACRO
- #define CHECK_AND_SET_JUMP_OFFSET(cx,cg,pc,off) \
- CHECK_AND_SET_JUMP_OFFSET_CUSTOM(cx,cg,pc,off,return JS_FALSE)
- #define CHECK_AND_SET_JUMP_OFFSET_AT_CUSTOM(cx,cg,off,BAD_EXIT) \
- CHECK_AND_SET_JUMP_OFFSET_CUSTOM(cx, cg, CG_CODE(cg,off), \
- CG_OFFSET(cg) - (off), BAD_EXIT)
- #define CHECK_AND_SET_JUMP_OFFSET_AT(cx,cg,off) \
- CHECK_AND_SET_JUMP_OFFSET_AT_CUSTOM(cx, cg, off, return JS_FALSE)
- extern JSBool
- js_SetJumpOffset(JSContext *cx, JSCodeGenerator *cg, jsbytecode *pc,
- ptrdiff_t off);
- /* Test whether we're in a statement of given type. */
- extern JSBool
- js_InStatement(JSTreeContext *tc, JSStmtType type);
- /* Test whether we're in a with statement. */
- #define js_InWithStatement(tc) js_InStatement(tc, STMT_WITH)
- /*
- * 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);
- /*
- * Push a block scope statement and link blockObj into tc->blockChain. To pop
- * this statement info record, use js_PopStatement as usual, or if appropriate
- * (if generating code), js_PopStatementCG.
- */
- extern void
- js_PushBlockScope(JSTreeContext *tc, JSStmtInfo *stmt, JSObject *blockObj,
- 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
- * unless the top statement info record represents a try-catch-finally suite.
- * 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_DefineCompileTimeConstant
- * calls will return the undefined value. js_DefineCompileTimeConstant 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);
- /*
- * Find a lexically scoped variable (one declared by let, catch, or an array
- * comprehension) named by atom, looking in tc's compile-time scopes.
- *
- * If a WITH statement is reached along the scope stack, return its statement
- * info record, so callers can tell that atom is ambiguous. If slotp is not
- * null, then if atom is found, set *slotp to its stack slot, otherwise to -1.
- * This means that if slotp is not null, all the block objects on the lexical
- * scope chain must have had their depth slots computed by the code generator,
- * so the caller must be under js_EmitTree.
- *
- * In any event, directly return the statement info record in which atom was
- * found. Otherwise return null.
- */
- extern JSStmtInfo *
- js_LexicalLookup(JSTreeContext *tc, JSAtom *atom, jsint *slotp);
- /*
- * Emit code into cg for the tree rooted at pn.
- */
- extern JSBool
- js_EmitTree(JSContext *cx, JSCodeGenerator *cg, JSParseNode *pn);
- /*
- * Emit function code using cg for the tree rooted at body.
- */
- extern JSBool
- js_EmitFunctionScript(JSContext *cx, JSCodeGenerator *cg, JSParseNode *body);
- /*
- * 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.
- *
- * Note on adding new source notes: every pair of bytecodes (A, B) where A and
- * B have disjoint sets of source notes that could apply to each bytecode may
- * reuse the same note type value for two notes (snA, snB) that have the same
- * arity, offsetBias, and isSpanDep initializers in js_SrcNoteSpec. This is
- * why SRC_IF and SRC_INITPROP have the same value below. For bad historical
- * reasons, some bytecodes below that could be overlayed have not been, but
- * before using SRC_EXTENDED, consider compressing the existing note types.
- *
- * Don't forget to update JSXDR_BYTECODE_VERSION in jsxdrapi.h for all such
- * incompatible source note or other bytecode changes.
- */
- typedef enum JSSrcNoteType {
- SRC_NULL = 0, /* terminates a note vector */
- SRC_IF = 1, /* JSOP_IFEQ bytecode is from an if-then */
- SRC_BREAK = 1, /* JSOP_GOTO is a break */
- SRC_INITPROP = 1, /* disjoint meaning applied to JSOP_INITELEM or
- to an index label in a regular (structuring)
- or a destructuring object initialiser */
- SRC_GENEXP = 1, /* JSOP_ANONFUNOBJ from generator expression */
- SRC_IF_ELSE = 2, /* JSOP_IFEQ bytecode is from an if-then-else */
- SRC_FOR_IN = 2, /* JSOP_GOTO to for-in loop condition from
- before loop (same arity as SRC_IF_ELSE) */
- SRC_FOR = 3, /* JSOP_NOP or JSOP_POP in for(;;) loop head */
- SRC_WHILE = 4, /* JSOP_GOTO to for or while loop condition
- from before loop, else JSOP_NOP at top of
- do-while loop */
- 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_DECL = 6, /* type of a declaration (var, const, let*) */
- SRC_DESTRUCT = 6, /* JSOP_DUP starting a destructuring assignment
- operation, with SRC_DECL_* offset operand */
- SRC_PCDELTA = 7, /* distance forward from comma-operator to
- next POP, or from CONDSWITCH to first CASE
- opcode, etc. -- always a forward delta */
- SRC_GROUPASSIGN = 7, /* SRC_DESTRUCT variant for [a, b] = [c, d] */
- SRC_ASSIGNOP = 8, /* += or another assign-op follows */
- SRC_COND = 9, /* JSOP_IFEQ is from conditional ?: operator */
- SRC_BRACE = 10, /* mandatory brace, for scope or to avoid
- dangling else */
- SRC_HIDDEN = 11, /* opcode shouldn't be decompiled */
- SRC_PCBASE = 12, /* distance back from annotated getprop or
- setprop op to left-most obj.prop.subprop
- bytecode -- always a backward delta */
- 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_EXTENDED = 21, /* extended source note, 32-159, in next byte */
- 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;
- /*
- * Constants for the SRC_DECL source note. Note that span-dependent bytecode
- * selection means that any SRC_DECL offset greater than SRC_DECL_LET may need
- * to be adjusted, but these "offsets" are too small to span a span-dependent
- * instruction, so can be used to denote distinct declaration syntaxes to the
- * decompiler.
- *
- * NB: the var_prefix array in jsopcode.c depends on these dense indexes from
- * SRC_DECL_VAR through SRC_DECL_LET.
- */
- #define SRC_DECL_VAR 0
- #define SRC_DECL_CONST 1
- #define SRC_DECL_LET 2
- #define SRC_DECL_NONE 3
- #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) ((JSSrcNoteType)(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 */
- int8 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);
- extern void
- js_FinishTakingTryNotes(JSCodeGenerator *cg, JSTryNoteArray *array);
- JS_END_EXTERN_C
- #endif /* jsemit_h___ */