1 |
/* $Header$ */
|
2 |
/*
|
3 |
* tclCompExpr.c --
|
4 |
*
|
5 |
* This file contains the code to compile Tcl expressions.
|
6 |
*
|
7 |
* Copyright (c) 1997 Sun Microsystems, Inc.
|
8 |
*
|
9 |
* See the file "license.terms" for information on usage and redistribution
|
10 |
* of this file, and for a DISCLAIMER OF ALL WARRANTIES.
|
11 |
*
|
12 |
* RCS: @(#) $Id: tclcompexpr.c,v 1.1.1.1 2001/06/13 04:35:43 dtashley Exp $
|
13 |
*/
|
14 |
|
15 |
#include "tclInt.h"
|
16 |
#include "tclCompile.h"
|
17 |
|
18 |
/*
|
19 |
* The stuff below is a bit of a hack so that this file can be used in
|
20 |
* environments that include no UNIX, i.e. no errno: just arrange to use
|
21 |
* the errno from tclExecute.c here.
|
22 |
*/
|
23 |
|
24 |
#ifndef TCL_GENERIC_ONLY
|
25 |
#include "tclPort.h"
|
26 |
#else
|
27 |
#define NO_ERRNO_H
|
28 |
#endif
|
29 |
|
30 |
#ifdef NO_ERRNO_H
|
31 |
extern int errno; /* Use errno from tclExecute.c. */
|
32 |
#define ERANGE 34
|
33 |
#endif
|
34 |
|
35 |
/*
|
36 |
* Boolean variable that controls whether expression compilation tracing
|
37 |
* is enabled.
|
38 |
*/
|
39 |
|
40 |
#ifdef TCL_COMPILE_DEBUG
|
41 |
static int traceExprComp = 0;
|
42 |
#endif /* TCL_COMPILE_DEBUG */
|
43 |
|
44 |
/*
|
45 |
* The ExprInfo structure describes the state of compiling an expression.
|
46 |
* A pointer to an ExprInfo record is passed among the routines in
|
47 |
* this module.
|
48 |
*/
|
49 |
|
50 |
typedef struct ExprInfo {
|
51 |
Tcl_Interp *interp; /* Used for error reporting. */
|
52 |
Tcl_Parse *parsePtr; /* Structure filled with information about
|
53 |
* the parsed expression. */
|
54 |
char *expr; /* The expression that was originally passed
|
55 |
* to TclCompileExpr. */
|
56 |
char *lastChar; /* Points just after last byte of expr. */
|
57 |
int hasOperators; /* Set 1 if the expr has operators; 0 if
|
58 |
* expr is only a primary. If 1 after
|
59 |
* compiling an expr, a tryCvtToNumeric
|
60 |
* instruction is emitted to convert the
|
61 |
* primary to a number if possible. */
|
62 |
int exprIsJustVarRef; /* Set 1 if the expr consists of just a
|
63 |
* variable reference as in the expression
|
64 |
* of "if $b then...". Otherwise 0. If 1 the
|
65 |
* expr is compiled out-of-line in order to
|
66 |
* implement expr's 2 level substitution
|
67 |
* semantics properly. */
|
68 |
int exprIsComparison; /* Set 1 if the top-level operator in the
|
69 |
* expr is a comparison. Otherwise 0. If 1,
|
70 |
* because the operands might be strings,
|
71 |
* the expr is compiled out-of-line in order
|
72 |
* to implement expr's 2 level substitution
|
73 |
* semantics properly. */
|
74 |
} ExprInfo;
|
75 |
|
76 |
/*
|
77 |
* Definitions of numeric codes representing each expression operator.
|
78 |
* The order of these must match the entries in the operatorTable below.
|
79 |
* Also the codes for the relational operators (OP_LESS, OP_GREATER,
|
80 |
* OP_LE, OP_GE, OP_EQ, and OP_NE) must be consecutive and in that order.
|
81 |
* Note that OP_PLUS and OP_MINUS represent both unary and binary operators.
|
82 |
*/
|
83 |
|
84 |
#define OP_MULT 0
|
85 |
#define OP_DIVIDE 1
|
86 |
#define OP_MOD 2
|
87 |
#define OP_PLUS 3
|
88 |
#define OP_MINUS 4
|
89 |
#define OP_LSHIFT 5
|
90 |
#define OP_RSHIFT 6
|
91 |
#define OP_LESS 7
|
92 |
#define OP_GREATER 8
|
93 |
#define OP_LE 9
|
94 |
#define OP_GE 10
|
95 |
#define OP_EQ 11
|
96 |
#define OP_NEQ 12
|
97 |
#define OP_BITAND 13
|
98 |
#define OP_BITXOR 14
|
99 |
#define OP_BITOR 15
|
100 |
#define OP_LAND 16
|
101 |
#define OP_LOR 17
|
102 |
#define OP_QUESTY 18
|
103 |
#define OP_LNOT 19
|
104 |
#define OP_BITNOT 20
|
105 |
|
106 |
/*
|
107 |
* Table describing the expression operators. Entries in this table must
|
108 |
* correspond to the definitions of numeric codes for operators just above.
|
109 |
*/
|
110 |
|
111 |
static int opTableInitialized = 0; /* 0 means not yet initialized. */
|
112 |
|
113 |
TCL_DECLARE_MUTEX(opMutex)
|
114 |
|
115 |
typedef struct OperatorDesc {
|
116 |
char *name; /* Name of the operator. */
|
117 |
int numOperands; /* Number of operands. 0 if the operator
|
118 |
* requires special handling. */
|
119 |
int instruction; /* Instruction opcode for the operator.
|
120 |
* Ignored if numOperands is 0. */
|
121 |
} OperatorDesc;
|
122 |
|
123 |
OperatorDesc operatorTable[] = {
|
124 |
{"*", 2, INST_MULT},
|
125 |
{"/", 2, INST_DIV},
|
126 |
{"%", 2, INST_MOD},
|
127 |
{"+", 0},
|
128 |
{"-", 0},
|
129 |
{"<<", 2, INST_LSHIFT},
|
130 |
{">>", 2, INST_RSHIFT},
|
131 |
{"<", 2, INST_LT},
|
132 |
{">", 2, INST_GT},
|
133 |
{"<=", 2, INST_LE},
|
134 |
{">=", 2, INST_GE},
|
135 |
{"==", 2, INST_EQ},
|
136 |
{"!=", 2, INST_NEQ},
|
137 |
{"&", 2, INST_BITAND},
|
138 |
{"^", 2, INST_BITXOR},
|
139 |
{"|", 2, INST_BITOR},
|
140 |
{"&&", 0},
|
141 |
{"||", 0},
|
142 |
{"?", 0},
|
143 |
{"!", 1, INST_LNOT},
|
144 |
{"~", 1, INST_BITNOT},
|
145 |
{NULL}
|
146 |
};
|
147 |
|
148 |
/*
|
149 |
* Hashtable used to map the names of expression operators to the index
|
150 |
* of their OperatorDesc description.
|
151 |
*/
|
152 |
|
153 |
static Tcl_HashTable opHashTable;
|
154 |
|
155 |
/*
|
156 |
* Declarations for local procedures to this file:
|
157 |
*/
|
158 |
|
159 |
static int CompileCondExpr _ANSI_ARGS_((
|
160 |
Tcl_Token *exprTokenPtr, ExprInfo *infoPtr,
|
161 |
CompileEnv *envPtr, Tcl_Token **endPtrPtr));
|
162 |
static int CompileLandOrLorExpr _ANSI_ARGS_((
|
163 |
Tcl_Token *exprTokenPtr, int opIndex,
|
164 |
ExprInfo *infoPtr, CompileEnv *envPtr,
|
165 |
Tcl_Token **endPtrPtr));
|
166 |
static int CompileMathFuncCall _ANSI_ARGS_((
|
167 |
Tcl_Token *exprTokenPtr, char *funcName,
|
168 |
ExprInfo *infoPtr, CompileEnv *envPtr,
|
169 |
Tcl_Token **endPtrPtr));
|
170 |
static int CompileSubExpr _ANSI_ARGS_((
|
171 |
Tcl_Token *exprTokenPtr, ExprInfo *infoPtr,
|
172 |
CompileEnv *envPtr));
|
173 |
static void LogSyntaxError _ANSI_ARGS_((ExprInfo *infoPtr));
|
174 |
|
175 |
/*
|
176 |
* Macro used to debug the execution of the expression compiler.
|
177 |
*/
|
178 |
|
179 |
#ifdef TCL_COMPILE_DEBUG
|
180 |
#define TRACE(exprBytes, exprLength, tokenBytes, tokenLength) \
|
181 |
if (traceExprComp) { \
|
182 |
fprintf(stderr, "CompileSubExpr: \"%.*s\", token \"%.*s\"\n", \
|
183 |
(exprLength), (exprBytes), (tokenLength), (tokenBytes)); \
|
184 |
}
|
185 |
#else
|
186 |
#define TRACE(exprBytes, exprLength, tokenBytes, tokenLength)
|
187 |
#endif /* TCL_COMPILE_DEBUG */
|
188 |
|
189 |
/*
|
190 |
*----------------------------------------------------------------------
|
191 |
*
|
192 |
* TclCompileExpr --
|
193 |
*
|
194 |
* This procedure compiles a string containing a Tcl expression into
|
195 |
* Tcl bytecodes. This procedure is the top-level interface to the
|
196 |
* the expression compilation module, and is used by such public
|
197 |
* procedures as Tcl_ExprString, Tcl_ExprStringObj, Tcl_ExprLong,
|
198 |
* Tcl_ExprDouble, Tcl_ExprBoolean, and Tcl_ExprBooleanObj.
|
199 |
*
|
200 |
* Results:
|
201 |
* The return value is TCL_OK on a successful compilation and TCL_ERROR
|
202 |
* on failure. If TCL_ERROR is returned, then the interpreter's result
|
203 |
* contains an error message.
|
204 |
*
|
205 |
* envPtr->maxStackDepth is updated with the maximum number of stack
|
206 |
* elements needed to execute the expression.
|
207 |
*
|
208 |
* envPtr->exprIsJustVarRef is set 1 if the expression consisted of
|
209 |
* a single variable reference as in the expression of "if $b then...".
|
210 |
* Otherwise it is set 0. This is used to implement Tcl's two level
|
211 |
* expression substitution semantics properly.
|
212 |
*
|
213 |
* envPtr->exprIsComparison is set 1 if the top-level operator in the
|
214 |
* expr is a comparison. Otherwise it is set 0. If 1, because the
|
215 |
* operands might be strings, the expr is compiled out-of-line in order
|
216 |
* to implement expr's 2 level substitution semantics properly.
|
217 |
*
|
218 |
* Side effects:
|
219 |
* Adds instructions to envPtr to evaluate the expression at runtime.
|
220 |
*
|
221 |
*----------------------------------------------------------------------
|
222 |
*/
|
223 |
|
224 |
int
|
225 |
TclCompileExpr(interp, script, numBytes, envPtr)
|
226 |
Tcl_Interp *interp; /* Used for error reporting. */
|
227 |
char *script; /* The source script to compile. */
|
228 |
int numBytes; /* Number of bytes in script. If < 0, the
|
229 |
* string consists of all bytes up to the
|
230 |
* first null character. */
|
231 |
CompileEnv *envPtr; /* Holds resulting instructions. */
|
232 |
{
|
233 |
ExprInfo info;
|
234 |
Tcl_Parse parse;
|
235 |
Tcl_HashEntry *hPtr;
|
236 |
int maxDepth, new, i, code;
|
237 |
|
238 |
/*
|
239 |
* If this is the first time we've been called, initialize the table
|
240 |
* of expression operators.
|
241 |
*/
|
242 |
|
243 |
if (numBytes < 0) {
|
244 |
numBytes = (script? strlen(script) : 0);
|
245 |
}
|
246 |
if (!opTableInitialized) {
|
247 |
Tcl_MutexLock(&opMutex);
|
248 |
if (!opTableInitialized) {
|
249 |
Tcl_InitHashTable(&opHashTable, TCL_STRING_KEYS);
|
250 |
for (i = 0; operatorTable[i].name != NULL; i++) {
|
251 |
hPtr = Tcl_CreateHashEntry(&opHashTable,
|
252 |
operatorTable[i].name, &new);
|
253 |
if (new) {
|
254 |
Tcl_SetHashValue(hPtr, (ClientData) i);
|
255 |
}
|
256 |
}
|
257 |
opTableInitialized = 1;
|
258 |
}
|
259 |
Tcl_MutexUnlock(&opMutex);
|
260 |
}
|
261 |
|
262 |
/*
|
263 |
* Initialize the structure containing information abvout this
|
264 |
* expression compilation.
|
265 |
*/
|
266 |
|
267 |
info.interp = interp;
|
268 |
info.parsePtr = &parse;
|
269 |
info.expr = script;
|
270 |
info.lastChar = (script + numBytes);
|
271 |
info.hasOperators = 0;
|
272 |
info.exprIsJustVarRef = 1; /* will be set 0 if anything else is seen */
|
273 |
info.exprIsComparison = 0;
|
274 |
|
275 |
/*
|
276 |
* Parse the expression then compile it.
|
277 |
*/
|
278 |
|
279 |
maxDepth = 0;
|
280 |
code = Tcl_ParseExpr(interp, script, numBytes, &parse);
|
281 |
if (code != TCL_OK) {
|
282 |
goto done;
|
283 |
}
|
284 |
|
285 |
code = CompileSubExpr(parse.tokenPtr, &info, envPtr);
|
286 |
if (code != TCL_OK) {
|
287 |
Tcl_FreeParse(&parse);
|
288 |
goto done;
|
289 |
}
|
290 |
maxDepth = envPtr->maxStackDepth;
|
291 |
|
292 |
if (!info.hasOperators) {
|
293 |
/*
|
294 |
* Attempt to convert the primary's object to an int or double.
|
295 |
* This is done in order to support Tcl's policy of interpreting
|
296 |
* operands if at all possible as first integers, else
|
297 |
* floating-point numbers.
|
298 |
*/
|
299 |
|
300 |
TclEmitOpcode(INST_TRY_CVT_TO_NUMERIC, envPtr);
|
301 |
}
|
302 |
Tcl_FreeParse(&parse);
|
303 |
|
304 |
done:
|
305 |
envPtr->maxStackDepth = maxDepth;
|
306 |
envPtr->exprIsJustVarRef = info.exprIsJustVarRef;
|
307 |
envPtr->exprIsComparison = info.exprIsComparison;
|
308 |
return code;
|
309 |
}
|
310 |
|
311 |
/*
|
312 |
*----------------------------------------------------------------------
|
313 |
*
|
314 |
* TclFinalizeCompilation --
|
315 |
*
|
316 |
* Clean up the compilation environment so it can later be
|
317 |
* properly reinitialized. This procedure is called by
|
318 |
* TclFinalizeCompExecEnv() in tclObj.c, which in turn is called
|
319 |
* by Tcl_Finalize().
|
320 |
*
|
321 |
* Results:
|
322 |
* None.
|
323 |
*
|
324 |
* Side effects:
|
325 |
* Cleans up the compilation environment. At the moment, just the
|
326 |
* table of expression operators is freed.
|
327 |
*
|
328 |
*----------------------------------------------------------------------
|
329 |
*/
|
330 |
|
331 |
void
|
332 |
TclFinalizeCompilation()
|
333 |
{
|
334 |
Tcl_MutexLock(&opMutex);
|
335 |
if (opTableInitialized) {
|
336 |
Tcl_DeleteHashTable(&opHashTable);
|
337 |
opTableInitialized = 0;
|
338 |
}
|
339 |
Tcl_MutexUnlock(&opMutex);
|
340 |
}
|
341 |
|
342 |
/*
|
343 |
*----------------------------------------------------------------------
|
344 |
*
|
345 |
* CompileSubExpr --
|
346 |
*
|
347 |
* Given a pointer to a TCL_TOKEN_SUB_EXPR token describing a
|
348 |
* subexpression, this procedure emits instructions to evaluate the
|
349 |
* subexpression at runtime.
|
350 |
*
|
351 |
* Results:
|
352 |
* The return value is TCL_OK on a successful compilation and TCL_ERROR
|
353 |
* on failure. If TCL_ERROR is returned, then the interpreter's result
|
354 |
* contains an error message.
|
355 |
*
|
356 |
* envPtr->maxStackDepth is updated with the maximum number of stack
|
357 |
* elements needed to execute the subexpression.
|
358 |
*
|
359 |
* envPtr->exprIsJustVarRef is set 1 if the subexpression consisted of
|
360 |
* a single variable reference as in the expression of "if $b then...".
|
361 |
* Otherwise it is set 0. This is used to implement Tcl's two level
|
362 |
* expression substitution semantics properly.
|
363 |
*
|
364 |
* envPtr->exprIsComparison is set 1 if the top-level operator in the
|
365 |
* subexpression is a comparison. Otherwise it is set 0. If 1, because
|
366 |
* the operands might be strings, the expr is compiled out-of-line in
|
367 |
* order to implement expr's 2 level substitution semantics properly.
|
368 |
*
|
369 |
* Side effects:
|
370 |
* Adds instructions to envPtr to evaluate the subexpression.
|
371 |
*
|
372 |
*----------------------------------------------------------------------
|
373 |
*/
|
374 |
|
375 |
static int
|
376 |
CompileSubExpr(exprTokenPtr, infoPtr, envPtr)
|
377 |
Tcl_Token *exprTokenPtr; /* Points to TCL_TOKEN_SUB_EXPR token
|
378 |
* to compile. */
|
379 |
ExprInfo *infoPtr; /* Describes the compilation state for the
|
380 |
* expression being compiled. */
|
381 |
CompileEnv *envPtr; /* Holds resulting instructions. */
|
382 |
{
|
383 |
Tcl_Interp *interp = infoPtr->interp;
|
384 |
Tcl_Token *tokenPtr, *endPtr, *afterSubexprPtr;
|
385 |
OperatorDesc *opDescPtr;
|
386 |
Tcl_HashEntry *hPtr;
|
387 |
char *operator;
|
388 |
char savedChar;
|
389 |
int maxDepth, objIndex, opIndex, length, code;
|
390 |
char buffer[TCL_UTF_MAX];
|
391 |
|
392 |
if (exprTokenPtr->type != TCL_TOKEN_SUB_EXPR) {
|
393 |
panic("CompileSubExpr: token type %d not TCL_TOKEN_SUB_EXPR\n",
|
394 |
exprTokenPtr->type);
|
395 |
}
|
396 |
maxDepth = 0;
|
397 |
code = TCL_OK;
|
398 |
|
399 |
/*
|
400 |
* Switch on the type of the first token after the subexpression token.
|
401 |
* After processing it, advance tokenPtr to point just after the
|
402 |
* subexpression's last token.
|
403 |
*/
|
404 |
|
405 |
tokenPtr = exprTokenPtr+1;
|
406 |
TRACE(exprTokenPtr->start, exprTokenPtr->size,
|
407 |
tokenPtr->start, tokenPtr->size);
|
408 |
switch (tokenPtr->type) {
|
409 |
case TCL_TOKEN_WORD:
|
410 |
code = TclCompileTokens(interp, tokenPtr+1,
|
411 |
tokenPtr->numComponents, envPtr);
|
412 |
if (code != TCL_OK) {
|
413 |
goto done;
|
414 |
}
|
415 |
maxDepth = envPtr->maxStackDepth;
|
416 |
tokenPtr += (tokenPtr->numComponents + 1);
|
417 |
infoPtr->exprIsJustVarRef = 0;
|
418 |
break;
|
419 |
|
420 |
case TCL_TOKEN_TEXT:
|
421 |
if (tokenPtr->size > 0) {
|
422 |
objIndex = TclRegisterLiteral(envPtr, tokenPtr->start,
|
423 |
tokenPtr->size, /*onHeap*/ 0);
|
424 |
} else {
|
425 |
objIndex = TclRegisterLiteral(envPtr, "", 0, /*onHeap*/ 0);
|
426 |
}
|
427 |
TclEmitPush(objIndex, envPtr);
|
428 |
maxDepth = 1;
|
429 |
tokenPtr += 1;
|
430 |
infoPtr->exprIsJustVarRef = 0;
|
431 |
break;
|
432 |
|
433 |
case TCL_TOKEN_BS:
|
434 |
length = Tcl_UtfBackslash(tokenPtr->start, (int *) NULL,
|
435 |
buffer);
|
436 |
if (length > 0) {
|
437 |
objIndex = TclRegisterLiteral(envPtr, buffer, length,
|
438 |
/*onHeap*/ 0);
|
439 |
} else {
|
440 |
objIndex = TclRegisterLiteral(envPtr, "", 0, /*onHeap*/ 0);
|
441 |
}
|
442 |
TclEmitPush(objIndex, envPtr);
|
443 |
maxDepth = 1;
|
444 |
tokenPtr += 1;
|
445 |
infoPtr->exprIsJustVarRef = 0;
|
446 |
break;
|
447 |
|
448 |
case TCL_TOKEN_COMMAND:
|
449 |
code = TclCompileScript(interp, tokenPtr->start+1,
|
450 |
tokenPtr->size-2, /*nested*/ 1, envPtr);
|
451 |
if (code != TCL_OK) {
|
452 |
goto done;
|
453 |
}
|
454 |
maxDepth = envPtr->maxStackDepth;
|
455 |
tokenPtr += 1;
|
456 |
infoPtr->exprIsJustVarRef = 0;
|
457 |
break;
|
458 |
|
459 |
case TCL_TOKEN_VARIABLE:
|
460 |
code = TclCompileTokens(interp, tokenPtr, 1, envPtr);
|
461 |
if (code != TCL_OK) {
|
462 |
goto done;
|
463 |
}
|
464 |
maxDepth = envPtr->maxStackDepth;
|
465 |
tokenPtr += (tokenPtr->numComponents + 1);
|
466 |
break;
|
467 |
|
468 |
case TCL_TOKEN_SUB_EXPR:
|
469 |
infoPtr->exprIsComparison = 0;
|
470 |
code = CompileSubExpr(tokenPtr, infoPtr, envPtr);
|
471 |
if (code != TCL_OK) {
|
472 |
goto done;
|
473 |
}
|
474 |
maxDepth = envPtr->maxStackDepth;
|
475 |
tokenPtr += (tokenPtr->numComponents + 1);
|
476 |
break;
|
477 |
|
478 |
case TCL_TOKEN_OPERATOR:
|
479 |
/*
|
480 |
* Look up the operator. Temporarily overwrite the character
|
481 |
* just after the end of the operator with a 0 byte. If the
|
482 |
* operator isn't found, treat it as a math function.
|
483 |
*/
|
484 |
|
485 |
/*
|
486 |
* TODO: Note that the string is modified in place. This is unsafe
|
487 |
* and will break if any of the routines called while the string is
|
488 |
* modified have side effects that depend on the original string
|
489 |
* being unmodified (e.g. adding an entry to the literal table).
|
490 |
*/
|
491 |
|
492 |
operator = tokenPtr->start;
|
493 |
savedChar = operator[tokenPtr->size];
|
494 |
operator[tokenPtr->size] = 0;
|
495 |
hPtr = Tcl_FindHashEntry(&opHashTable, operator);
|
496 |
if (hPtr == NULL) {
|
497 |
code = CompileMathFuncCall(exprTokenPtr, operator, infoPtr,
|
498 |
envPtr, &endPtr);
|
499 |
operator[tokenPtr->size] = (char) savedChar;
|
500 |
if (code != TCL_OK) {
|
501 |
goto done;
|
502 |
}
|
503 |
maxDepth = envPtr->maxStackDepth;
|
504 |
tokenPtr = endPtr;
|
505 |
infoPtr->exprIsJustVarRef = 0;
|
506 |
infoPtr->exprIsComparison = 0;
|
507 |
break;
|
508 |
}
|
509 |
operator[tokenPtr->size] = (char) savedChar;
|
510 |
opIndex = (int) Tcl_GetHashValue(hPtr);
|
511 |
opDescPtr = &(operatorTable[opIndex]);
|
512 |
|
513 |
/*
|
514 |
* If the operator is "normal", compile it using information
|
515 |
* from the operator table.
|
516 |
*/
|
517 |
|
518 |
if (opDescPtr->numOperands > 0) {
|
519 |
tokenPtr++;
|
520 |
code = CompileSubExpr(tokenPtr, infoPtr, envPtr);
|
521 |
if (code != TCL_OK) {
|
522 |
goto done;
|
523 |
}
|
524 |
maxDepth = envPtr->maxStackDepth;
|
525 |
tokenPtr += (tokenPtr->numComponents + 1);
|
526 |
|
527 |
if (opDescPtr->numOperands == 2) {
|
528 |
code = CompileSubExpr(tokenPtr, infoPtr, envPtr);
|
529 |
if (code != TCL_OK) {
|
530 |
goto done;
|
531 |
}
|
532 |
maxDepth = TclMax((envPtr->maxStackDepth + 1),
|
533 |
maxDepth);
|
534 |
tokenPtr += (tokenPtr->numComponents + 1);
|
535 |
}
|
536 |
TclEmitOpcode(opDescPtr->instruction, envPtr);
|
537 |
infoPtr->hasOperators = 1;
|
538 |
infoPtr->exprIsJustVarRef = 0;
|
539 |
infoPtr->exprIsComparison =
|
540 |
((opIndex >= OP_LESS) && (opIndex <= OP_NEQ));
|
541 |
break;
|
542 |
}
|
543 |
|
544 |
/*
|
545 |
* The operator requires special treatment, and is either
|
546 |
* "+" or "-", or one of "&&", "||" or "?".
|
547 |
*/
|
548 |
|
549 |
switch (opIndex) {
|
550 |
case OP_PLUS:
|
551 |
case OP_MINUS:
|
552 |
tokenPtr++;
|
553 |
code = CompileSubExpr(tokenPtr, infoPtr, envPtr);
|
554 |
if (code != TCL_OK) {
|
555 |
goto done;
|
556 |
}
|
557 |
maxDepth = envPtr->maxStackDepth;
|
558 |
tokenPtr += (tokenPtr->numComponents + 1);
|
559 |
|
560 |
/*
|
561 |
* Check whether the "+" or "-" is unary.
|
562 |
*/
|
563 |
|
564 |
afterSubexprPtr = exprTokenPtr
|
565 |
+ exprTokenPtr->numComponents+1;
|
566 |
if (tokenPtr == afterSubexprPtr) {
|
567 |
TclEmitOpcode(((opIndex==OP_PLUS)?
|
568 |
INST_UPLUS : INST_UMINUS),
|
569 |
envPtr);
|
570 |
break;
|
571 |
}
|
572 |
|
573 |
/*
|
574 |
* The "+" or "-" is binary.
|
575 |
*/
|
576 |
|
577 |
code = CompileSubExpr(tokenPtr, infoPtr, envPtr);
|
578 |
if (code != TCL_OK) {
|
579 |
goto done;
|
580 |
}
|
581 |
maxDepth = TclMax((envPtr->maxStackDepth + 1),
|
582 |
maxDepth);
|
583 |
tokenPtr += (tokenPtr->numComponents + 1);
|
584 |
TclEmitOpcode(((opIndex==OP_PLUS)? INST_ADD : INST_SUB),
|
585 |
envPtr);
|
586 |
break;
|
587 |
|
588 |
case OP_LAND:
|
589 |
case OP_LOR:
|
590 |
code = CompileLandOrLorExpr(exprTokenPtr, opIndex,
|
591 |
infoPtr, envPtr, &endPtr);
|
592 |
if (code != TCL_OK) {
|
593 |
goto done;
|
594 |
}
|
595 |
maxDepth = envPtr->maxStackDepth;
|
596 |
tokenPtr = endPtr;
|
597 |
break;
|
598 |
|
599 |
case OP_QUESTY:
|
600 |
code = CompileCondExpr(exprTokenPtr, infoPtr,
|
601 |
envPtr, &endPtr);
|
602 |
if (code != TCL_OK) {
|
603 |
goto done;
|
604 |
}
|
605 |
maxDepth = envPtr->maxStackDepth;
|
606 |
tokenPtr = endPtr;
|
607 |
break;
|
608 |
|
609 |
default:
|
610 |
panic("CompileSubExpr: unexpected operator %d requiring special treatment\n",
|
611 |
opIndex);
|
612 |
} /* end switch on operator requiring special treatment */
|
613 |
infoPtr->hasOperators = 1;
|
614 |
infoPtr->exprIsJustVarRef = 0;
|
615 |
infoPtr->exprIsComparison = 0;
|
616 |
break;
|
617 |
|
618 |
default:
|
619 |
panic("CompileSubExpr: unexpected token type %d\n",
|
620 |
tokenPtr->type);
|
621 |
}
|
622 |
|
623 |
/*
|
624 |
* Verify that the subexpression token had the required number of
|
625 |
* subtokens: that we've advanced tokenPtr just beyond the
|
626 |
* subexpression's last token. For example, a "*" subexpression must
|
627 |
* contain the tokens for exactly two operands.
|
628 |
*/
|
629 |
|
630 |
if (tokenPtr != (exprTokenPtr + exprTokenPtr->numComponents+1)) {
|
631 |
LogSyntaxError(infoPtr);
|
632 |
code = TCL_ERROR;
|
633 |
}
|
634 |
|
635 |
done:
|
636 |
envPtr->maxStackDepth = maxDepth;
|
637 |
return code;
|
638 |
}
|
639 |
|
640 |
/*
|
641 |
*----------------------------------------------------------------------
|
642 |
*
|
643 |
* CompileLandOrLorExpr --
|
644 |
*
|
645 |
* This procedure compiles a Tcl logical and ("&&") or logical or
|
646 |
* ("||") subexpression.
|
647 |
*
|
648 |
* Results:
|
649 |
* The return value is TCL_OK on a successful compilation and TCL_ERROR
|
650 |
* on failure. If TCL_OK is returned, a pointer to the token just after
|
651 |
* the last one in the subexpression is stored at the address in
|
652 |
* endPtrPtr. If TCL_ERROR is returned, then the interpreter's result
|
653 |
* contains an error message.
|
654 |
*
|
655 |
* envPtr->maxStackDepth is updated with the maximum number of stack
|
656 |
* elements needed to execute the expression.
|
657 |
*
|
658 |
* Side effects:
|
659 |
* Adds instructions to envPtr to evaluate the expression at runtime.
|
660 |
*
|
661 |
*----------------------------------------------------------------------
|
662 |
*/
|
663 |
|
664 |
static int
|
665 |
CompileLandOrLorExpr(exprTokenPtr, opIndex, infoPtr, envPtr, endPtrPtr)
|
666 |
Tcl_Token *exprTokenPtr; /* Points to TCL_TOKEN_SUB_EXPR token
|
667 |
* containing the "&&" or "||" operator. */
|
668 |
int opIndex; /* A code describing the expression
|
669 |
* operator: either OP_LAND or OP_LOR. */
|
670 |
ExprInfo *infoPtr; /* Describes the compilation state for the
|
671 |
* expression being compiled. */
|
672 |
CompileEnv *envPtr; /* Holds resulting instructions. */
|
673 |
Tcl_Token **endPtrPtr; /* If successful, a pointer to the token
|
674 |
* just after the last token in the
|
675 |
* subexpression is stored here. */
|
676 |
{
|
677 |
JumpFixup shortCircuitFixup; /* Used to fix up the short circuit jump
|
678 |
* after the first subexpression. */
|
679 |
JumpFixup lhsTrueFixup, lhsEndFixup;
|
680 |
/* Used to fix up jumps used to convert the
|
681 |
* first operand to 0 or 1. */
|
682 |
Tcl_Token *tokenPtr;
|
683 |
int dist, maxDepth, code;
|
684 |
|
685 |
/*
|
686 |
* Emit code for the first operand.
|
687 |
*/
|
688 |
|
689 |
maxDepth = 0;
|
690 |
tokenPtr = exprTokenPtr+2;
|
691 |
code = CompileSubExpr(tokenPtr, infoPtr, envPtr);
|
692 |
if (code != TCL_OK) {
|
693 |
goto done;
|
694 |
}
|
695 |
maxDepth = envPtr->maxStackDepth;
|
696 |
tokenPtr += (tokenPtr->numComponents + 1);
|
697 |
|
698 |
/*
|
699 |
* Convert the first operand to the result that Tcl requires:
|
700 |
* "0" or "1". Eventually we'll use a new instruction for this.
|
701 |
*/
|
702 |
|
703 |
TclEmitForwardJump(envPtr, TCL_TRUE_JUMP, &lhsTrueFixup);
|
704 |
TclEmitPush(TclRegisterLiteral(envPtr, "0", 1, /*onHeap*/ 0), envPtr);
|
705 |
TclEmitForwardJump(envPtr, TCL_UNCONDITIONAL_JUMP, &lhsEndFixup);
|
706 |
dist = (envPtr->codeNext - envPtr->codeStart) - lhsTrueFixup.codeOffset;
|
707 |
if (TclFixupForwardJump(envPtr, &lhsTrueFixup, dist, 127)) {
|
708 |
badDist:
|
709 |
panic("CompileLandOrLorExpr: bad jump distance %d\n", dist);
|
710 |
}
|
711 |
TclEmitPush(TclRegisterLiteral(envPtr, "1", 1, /*onHeap*/ 0), envPtr);
|
712 |
dist = (envPtr->codeNext - envPtr->codeStart) - lhsEndFixup.codeOffset;
|
713 |
if (TclFixupForwardJump(envPtr, &lhsEndFixup, dist, 127)) {
|
714 |
goto badDist;
|
715 |
}
|
716 |
|
717 |
/*
|
718 |
* Emit the "short circuit" jump around the rest of the expression.
|
719 |
* Duplicate the "0" or "1" on top of the stack first to keep the
|
720 |
* jump from consuming it.
|
721 |
*/
|
722 |
|
723 |
TclEmitOpcode(INST_DUP, envPtr);
|
724 |
TclEmitForwardJump(envPtr,
|
725 |
((opIndex==OP_LAND)? TCL_FALSE_JUMP : TCL_TRUE_JUMP),
|
726 |
&shortCircuitFixup);
|
727 |
|
728 |
/*
|
729 |
* Emit code for the second operand.
|
730 |
*/
|
731 |
|
732 |
code = CompileSubExpr(tokenPtr, infoPtr, envPtr);
|
733 |
if (code != TCL_OK) {
|
734 |
goto done;
|
735 |
}
|
736 |
maxDepth = TclMax((envPtr->maxStackDepth + 1), maxDepth);
|
737 |
tokenPtr += (tokenPtr->numComponents + 1);
|
738 |
|
739 |
/*
|
740 |
* Emit a "logical and" or "logical or" instruction. This does not try
|
741 |
* to "short- circuit" the evaluation of both operands, but instead
|
742 |
* ensures that we either have a "1" or a "0" result.
|
743 |
*/
|
744 |
|
745 |
TclEmitOpcode(((opIndex==OP_LAND)? INST_LAND : INST_LOR), envPtr);
|
746 |
|
747 |
/*
|
748 |
* Now that we know the target of the forward jump, update it with the
|
749 |
* correct distance.
|
750 |
*/
|
751 |
|
752 |
dist = (envPtr->codeNext - envPtr->codeStart)
|
753 |
- shortCircuitFixup.codeOffset;
|
754 |
TclFixupForwardJump(envPtr, &shortCircuitFixup, dist, 127);
|
755 |
*endPtrPtr = tokenPtr;
|
756 |
|
757 |
done:
|
758 |
envPtr->maxStackDepth = maxDepth;
|
759 |
return code;
|
760 |
}
|
761 |
|
762 |
/*
|
763 |
*----------------------------------------------------------------------
|
764 |
*
|
765 |
* CompileCondExpr --
|
766 |
*
|
767 |
* This procedure compiles a Tcl conditional expression:
|
768 |
* condExpr ::= lorExpr ['?' condExpr ':' condExpr]
|
769 |
*
|
770 |
* Results:
|
771 |
* The return value is TCL_OK on a successful compilation and TCL_ERROR
|
772 |
* on failure. If TCL_OK is returned, a pointer to the token just after
|
773 |
* the last one in the subexpression is stored at the address in
|
774 |
* endPtrPtr. If TCL_ERROR is returned, then the interpreter's result
|
775 |
* contains an error message.
|
776 |
*
|
777 |
* envPtr->maxStackDepth is updated with the maximum number of stack
|
778 |
* elements needed to execute the expression.
|
779 |
*
|
780 |
* Side effects:
|
781 |
* Adds instructions to envPtr to evaluate the expression at runtime.
|
782 |
*
|
783 |
*----------------------------------------------------------------------
|
784 |
*/
|
785 |
|
786 |
static int
|
787 |
CompileCondExpr(exprTokenPtr, infoPtr, envPtr, endPtrPtr)
|
788 |
Tcl_Token *exprTokenPtr; /* Points to TCL_TOKEN_SUB_EXPR token
|
789 |
* containing the "?" operator. */
|
790 |
ExprInfo *infoPtr; /* Describes the compilation state for the
|
791 |
* expression being compiled. */
|
792 |
CompileEnv *envPtr; /* Holds resulting instructions. */
|
793 |
Tcl_Token **endPtrPtr; /* If successful, a pointer to the token
|
794 |
* just after the last token in the
|
795 |
* subexpression is stored here. */
|
796 |
{
|
797 |
JumpFixup jumpAroundThenFixup, jumpAroundElseFixup;
|
798 |
/* Used to update or replace one-byte jumps
|
799 |
* around the then and else expressions when
|
800 |
* their target PCs are determined. */
|
801 |
Tcl_Token *tokenPtr;
|
802 |
int elseCodeOffset, dist, maxDepth, code;
|
803 |
|
804 |
/*
|
805 |
* Emit code for the test.
|
806 |
*/
|
807 |
|
808 |
maxDepth = 0;
|
809 |
tokenPtr = exprTokenPtr+2;
|
810 |
code = CompileSubExpr(tokenPtr, infoPtr, envPtr);
|
811 |
if (code != TCL_OK) {
|
812 |
goto done;
|
813 |
}
|
814 |
maxDepth = envPtr->maxStackDepth;
|
815 |
tokenPtr += (tokenPtr->numComponents + 1);
|
816 |
|
817 |
/*
|
818 |
* Emit the jump to the "else" expression if the test was false.
|
819 |
*/
|
820 |
|
821 |
TclEmitForwardJump(envPtr, TCL_FALSE_JUMP, &jumpAroundThenFixup);
|
822 |
|
823 |
/*
|
824 |
* Compile the "then" expression. Note that if a subexpression is only
|
825 |
* a primary, we need to try to convert it to numeric. We do this to
|
826 |
* support Tcl's policy of interpreting operands if at all possible as
|
827 |
* first integers, else floating-point numbers.
|
828 |
*/
|
829 |
|
830 |
infoPtr->hasOperators = 0;
|
831 |
code = CompileSubExpr(tokenPtr, infoPtr, envPtr);
|
832 |
if (code != TCL_OK) {
|
833 |
goto done;
|
834 |
}
|
835 |
maxDepth = TclMax(envPtr->maxStackDepth, maxDepth);
|
836 |
tokenPtr += (tokenPtr->numComponents + 1);
|
837 |
if (!infoPtr->hasOperators) {
|
838 |
TclEmitOpcode(INST_TRY_CVT_TO_NUMERIC, envPtr);
|
839 |
}
|
840 |
|
841 |
/*
|
842 |
* Emit an unconditional jump around the "else" condExpr.
|
843 |
*/
|
844 |
|
845 |
TclEmitForwardJump(envPtr, TCL_UNCONDITIONAL_JUMP,
|
846 |
&jumpAroundElseFixup);
|
847 |
|
848 |
/*
|
849 |
* Compile the "else" expression.
|
850 |
*/
|
851 |
|
852 |
elseCodeOffset = (envPtr->codeNext - envPtr->codeStart);
|
853 |
infoPtr->hasOperators = 0;
|
854 |
code = CompileSubExpr(tokenPtr, infoPtr, envPtr);
|
855 |
if (code != TCL_OK) {
|
856 |
goto done;
|
857 |
}
|
858 |
maxDepth = TclMax(envPtr->maxStackDepth, maxDepth);
|
859 |
tokenPtr += (tokenPtr->numComponents + 1);
|
860 |
if (!infoPtr->hasOperators) {
|
861 |
TclEmitOpcode(INST_TRY_CVT_TO_NUMERIC, envPtr);
|
862 |
}
|
863 |
|
864 |
/*
|
865 |
* Fix up the second jump around the "else" expression.
|
866 |
*/
|
867 |
|
868 |
dist = (envPtr->codeNext - envPtr->codeStart)
|
869 |
- jumpAroundElseFixup.codeOffset;
|
870 |
if (TclFixupForwardJump(envPtr, &jumpAroundElseFixup, dist, 127)) {
|
871 |
/*
|
872 |
* Update the else expression's starting code offset since it
|
873 |
* moved down 3 bytes too.
|
874 |
*/
|
875 |
|
876 |
elseCodeOffset += 3;
|
877 |
}
|
878 |
|
879 |
/*
|
880 |
* Fix up the first jump to the "else" expression if the test was false.
|
881 |
*/
|
882 |
|
883 |
dist = (elseCodeOffset - jumpAroundThenFixup.codeOffset);
|
884 |
TclFixupForwardJump(envPtr, &jumpAroundThenFixup, dist, 127);
|
885 |
*endPtrPtr = tokenPtr;
|
886 |
|
887 |
done:
|
888 |
envPtr->maxStackDepth = maxDepth;
|
889 |
return code;
|
890 |
}
|
891 |
|
892 |
/*
|
893 |
*----------------------------------------------------------------------
|
894 |
*
|
895 |
* CompileMathFuncCall --
|
896 |
*
|
897 |
* This procedure compiles a call on a math function in an expression:
|
898 |
* mathFuncCall ::= funcName '(' [condExpr {',' condExpr}] ')'
|
899 |
*
|
900 |
* Results:
|
901 |
* The return value is TCL_OK on a successful compilation and TCL_ERROR
|
902 |
* on failure. If TCL_OK is returned, a pointer to the token just after
|
903 |
* the last one in the subexpression is stored at the address in
|
904 |
* endPtrPtr. If TCL_ERROR is returned, then the interpreter's result
|
905 |
* contains an error message.
|
906 |
*
|
907 |
* envPtr->maxStackDepth is updated with the maximum number of stack
|
908 |
* elements needed to execute the function.
|
909 |
*
|
910 |
* Side effects:
|
911 |
* Adds instructions to envPtr to evaluate the math function at
|
912 |
* runtime.
|
913 |
*
|
914 |
*----------------------------------------------------------------------
|
915 |
*/
|
916 |
|
917 |
static int
|
918 |
CompileMathFuncCall(exprTokenPtr, funcName, infoPtr, envPtr, endPtrPtr)
|
919 |
Tcl_Token *exprTokenPtr; /* Points to TCL_TOKEN_SUB_EXPR token
|
920 |
* containing the math function call. */
|
921 |
char *funcName; /* Name of the math function. */
|
922 |
ExprInfo *infoPtr; /* Describes the compilation state for the
|
923 |
* expression being compiled. */
|
924 |
CompileEnv *envPtr; /* Holds resulting instructions. */
|
925 |
Tcl_Token **endPtrPtr; /* If successful, a pointer to the token
|
926 |
* just after the last token in the
|
927 |
* subexpression is stored here. */
|
928 |
{
|
929 |
Tcl_Interp *interp = infoPtr->interp;
|
930 |
Interp *iPtr = (Interp *) interp;
|
931 |
MathFunc *mathFuncPtr;
|
932 |
Tcl_HashEntry *hPtr;
|
933 |
Tcl_Token *tokenPtr, *afterSubexprPtr;
|
934 |
int maxDepth, code, i;
|
935 |
|
936 |
/*
|
937 |
* Look up the MathFunc record for the function.
|
938 |
*/
|
939 |
|
940 |
code = TCL_OK;
|
941 |
maxDepth = 0;
|
942 |
hPtr = Tcl_FindHashEntry(&iPtr->mathFuncTable, funcName);
|
943 |
if (hPtr == NULL) {
|
944 |
Tcl_AppendStringsToObj(Tcl_GetObjResult(interp),
|
945 |
"unknown math function \"", funcName, "\"", (char *) NULL);
|
946 |
code = TCL_ERROR;
|
947 |
goto done;
|
948 |
}
|
949 |
mathFuncPtr = (MathFunc *) Tcl_GetHashValue(hPtr);
|
950 |
|
951 |
/*
|
952 |
* If not a builtin function, push an object with the function's name.
|
953 |
*/
|
954 |
|
955 |
if (mathFuncPtr->builtinFuncIndex < 0) {
|
956 |
TclEmitPush(TclRegisterLiteral(envPtr, funcName, -1, /*onHeap*/ 0),
|
957 |
envPtr);
|
958 |
maxDepth = 1;
|
959 |
}
|
960 |
|
961 |
/*
|
962 |
* Compile any arguments for the function.
|
963 |
*/
|
964 |
|
965 |
tokenPtr = exprTokenPtr+2;
|
966 |
afterSubexprPtr = exprTokenPtr + (exprTokenPtr->numComponents + 1);
|
967 |
if (mathFuncPtr->numArgs > 0) {
|
968 |
for (i = 0; i < mathFuncPtr->numArgs; i++) {
|
969 |
if (tokenPtr == afterSubexprPtr) {
|
970 |
Tcl_ResetResult(interp);
|
971 |
Tcl_AppendToObj(Tcl_GetObjResult(interp),
|
972 |
"too few arguments for math function", -1);
|
973 |
code = TCL_ERROR;
|
974 |
goto done;
|
975 |
}
|
976 |
infoPtr->exprIsComparison = 0;
|
977 |
code = CompileSubExpr(tokenPtr, infoPtr, envPtr);
|
978 |
if (code != TCL_OK) {
|
979 |
goto done;
|
980 |
}
|
981 |
tokenPtr += (tokenPtr->numComponents + 1);
|
982 |
maxDepth++;
|
983 |
}
|
984 |
if (tokenPtr != afterSubexprPtr) {
|
985 |
Tcl_ResetResult(interp);
|
986 |
Tcl_AppendToObj(Tcl_GetObjResult(interp),
|
987 |
"too many arguments for math function", -1);
|
988 |
code = TCL_ERROR;
|
989 |
goto done;
|
990 |
}
|
991 |
} else if (tokenPtr != afterSubexprPtr) {
|
992 |
Tcl_ResetResult(interp);
|
993 |
Tcl_AppendToObj(Tcl_GetObjResult(interp),
|
994 |
"too many arguments for math function", -1);
|
995 |
code = TCL_ERROR;
|
996 |
goto done;
|
997 |
}
|
998 |
|
999 |
/*
|
1000 |
* Compile the call on the math function. Note that the "objc" argument
|
1001 |
* count for non-builtin functions is incremented by 1 to include the
|
1002 |
* function name itself.
|
1003 |
*/
|
1004 |
|
1005 |
if (mathFuncPtr->builtinFuncIndex >= 0) { /* a builtin function */
|
1006 |
TclEmitInstInt1(INST_CALL_BUILTIN_FUNC1,
|
1007 |
mathFuncPtr->builtinFuncIndex, envPtr);
|
1008 |
} else {
|
1009 |
TclEmitInstInt1(INST_CALL_FUNC1, (mathFuncPtr->numArgs+1), envPtr);
|
1010 |
}
|
1011 |
*endPtrPtr = afterSubexprPtr;
|
1012 |
|
1013 |
done:
|
1014 |
envPtr->maxStackDepth = maxDepth;
|
1015 |
return code;
|
1016 |
}
|
1017 |
|
1018 |
/*
|
1019 |
*----------------------------------------------------------------------
|
1020 |
*
|
1021 |
* LogSyntaxError --
|
1022 |
*
|
1023 |
* This procedure is invoked after an error occurs when compiling an
|
1024 |
* expression. It sets the interpreter result to an error message
|
1025 |
* describing the error.
|
1026 |
*
|
1027 |
* Results:
|
1028 |
* None.
|
1029 |
*
|
1030 |
* Side effects:
|
1031 |
* Sets the interpreter result to an error message describing the
|
1032 |
* expression that was being compiled when the error occurred.
|
1033 |
*
|
1034 |
*----------------------------------------------------------------------
|
1035 |
*/
|
1036 |
|
1037 |
static void
|
1038 |
LogSyntaxError(infoPtr)
|
1039 |
ExprInfo *infoPtr; /* Describes the compilation state for the
|
1040 |
* expression being compiled. */
|
1041 |
{
|
1042 |
int numBytes = (infoPtr->lastChar - infoPtr->expr);
|
1043 |
char buffer[100];
|
1044 |
|
1045 |
sprintf(buffer, "syntax error in expression \"%.*s\"",
|
1046 |
((numBytes > 60)? 60 : numBytes), infoPtr->expr);
|
1047 |
Tcl_AppendStringsToObj(Tcl_GetObjResult(infoPtr->interp),
|
1048 |
buffer, (char *) NULL);
|
1049 |
}
|
1050 |
|
1051 |
/* End of tclcompexpr.c */
|