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freebsd-dev/contrib/tcl/generic/tclCompExpr.c
Poul-Henning Kamp 539e1e66ff Upgrade to 8.0 release.
1997-10-01 13:19:13 +00:00

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/*
* tclCompExpr.c --
*
* This file contains the code to compile Tcl expressions.
*
* Copyright (c) 1996-1997 Sun Microsystems, Inc.
*
* See the file "license.terms" for information on usage and redistribution
* of this file, and for a DISCLAIMER OF ALL WARRANTIES.
*
* SCCS: @(#) tclCompExpr.c 1.31 97/08/07 10:14:07
*/
#include "tclInt.h"
#include "tclCompile.h"
/*
* The stuff below is a bit of a hack so that this file can be used in
* environments that include no UNIX, i.e. no errno: just arrange to use
* the errno from tclExecute.c here.
*/
#ifndef TCL_GENERIC_ONLY
#include "tclPort.h"
#else
#define NO_ERRNO_H
#endif
#ifdef NO_ERRNO_H
extern int errno; /* Use errno from tclExecute.c. */
#define ERANGE 34
#endif
/*
* Boolean variable that controls whether expression compilation tracing
* is enabled.
*/
#ifdef TCL_COMPILE_DEBUG
static int traceCompileExpr = 0;
#endif /* TCL_COMPILE_DEBUG */
/*
* The ExprInfo structure describes the state of compiling an expression.
* A pointer to an ExprInfo record is passed among the routines in
* this module.
*/
typedef struct ExprInfo {
int token; /* Type of the last token parsed in expr.
* See below for definitions. Corresponds
* to the characters just before next. */
int objIndex; /* If token is a literal value, the index of
* an object holding the value in the code's
* object table; otherwise is NULL. */
char *funcName; /* If the token is FUNC_NAME, points to the
* first character of the math function's
* name; otherwise is NULL. */
char *next; /* Position of the next character to be
* scanned in the expression string. */
char *originalExpr; /* The entire expression that was originally
* passed to Tcl_ExprString et al. */
char *lastChar; /* Pointer to terminating null in
* originalExpr. */
int hasOperators; /* Set 1 if the expr has operators; 0 if
* expr is only a primary. If 1 after
* compiling an expr, a tryCvtToNumeric
* instruction is emitted to convert the
* primary to a number if possible. */
int exprIsJustVarRef; /* Set 1 if the expr consists of just a
* variable reference as in the expression
* of "if $b then...". Otherwise 0. If 1 the
* expr is compiled out-of-line in order to
* implement expr's 2 level substitution
* semantics properly. */
int exprIsComparison; /* Set 1 if the top-level operator in the
* expr is a comparison. Otherwise 0. If 1,
* because the operands might be strings,
* the expr is compiled out-of-line in order
* to implement expr's 2 level substitution
* semantics properly. */
} ExprInfo;
/*
* Definitions of the different tokens that appear in expressions. The order
* of these must match the corresponding entries in the operatorStrings
* array below.
*/
#define LITERAL 0
#define FUNC_NAME (LITERAL + 1)
#define OPEN_BRACKET (LITERAL + 2)
#define CLOSE_BRACKET (LITERAL + 3)
#define OPEN_PAREN (LITERAL + 4)
#define CLOSE_PAREN (LITERAL + 5)
#define DOLLAR (LITERAL + 6)
#define QUOTE (LITERAL + 7)
#define COMMA (LITERAL + 8)
#define END (LITERAL + 9)
#define UNKNOWN (LITERAL + 10)
/*
* Binary operators:
*/
#define MULT (UNKNOWN + 1)
#define DIVIDE (MULT + 1)
#define MOD (MULT + 2)
#define PLUS (MULT + 3)
#define MINUS (MULT + 4)
#define LEFT_SHIFT (MULT + 5)
#define RIGHT_SHIFT (MULT + 6)
#define LESS (MULT + 7)
#define GREATER (MULT + 8)
#define LEQ (MULT + 9)
#define GEQ (MULT + 10)
#define EQUAL (MULT + 11)
#define NEQ (MULT + 12)
#define BIT_AND (MULT + 13)
#define BIT_XOR (MULT + 14)
#define BIT_OR (MULT + 15)
#define AND (MULT + 16)
#define OR (MULT + 17)
#define QUESTY (MULT + 18)
#define COLON (MULT + 19)
/*
* Unary operators. Unary minus and plus are represented by the (binary)
* tokens MINUS and PLUS.
*/
#define NOT (COLON + 1)
#define BIT_NOT (NOT + 1)
/*
* Mapping from tokens to strings; used for debugging messages. These
* entries must match the order and number of the token definitions above.
*/
#ifdef TCL_COMPILE_DEBUG
static char *tokenStrings[] = {
"LITERAL", "FUNCNAME",
"[", "]", "(", ")", "$", "\"", ",", "END", "UNKNOWN",
"*", "/", "%", "+", "-",
"<<", ">>", "<", ">", "<=", ">=", "==", "!=",
"&", "^", "|", "&&", "||", "?", ":",
"!", "~"
};
#endif /* TCL_COMPILE_DEBUG */
/*
* Declarations for local procedures to this file:
*/
static int CompileAddExpr _ANSI_ARGS_((Tcl_Interp *interp,
ExprInfo *infoPtr, int flags,
CompileEnv *envPtr));
static int CompileBitAndExpr _ANSI_ARGS_((Tcl_Interp *interp,
ExprInfo *infoPtr, int flags,
CompileEnv *envPtr));
static int CompileBitOrExpr _ANSI_ARGS_((Tcl_Interp *interp,
ExprInfo *infoPtr, int flags,
CompileEnv *envPtr));
static int CompileBitXorExpr _ANSI_ARGS_((Tcl_Interp *interp,
ExprInfo *infoPtr, int flags,
CompileEnv *envPtr));
static int CompileCondExpr _ANSI_ARGS_((Tcl_Interp *interp,
ExprInfo *infoPtr, int flags,
CompileEnv *envPtr));
static int CompileEqualityExpr _ANSI_ARGS_((Tcl_Interp *interp,
ExprInfo *infoPtr, int flags,
CompileEnv *envPtr));
static int CompileLandExpr _ANSI_ARGS_((Tcl_Interp *interp,
ExprInfo *infoPtr, int flags,
CompileEnv *envPtr));
static int CompileLorExpr _ANSI_ARGS_((Tcl_Interp *interp,
ExprInfo *infoPtr, int flags,
CompileEnv *envPtr));
static int CompileMathFuncCall _ANSI_ARGS_((Tcl_Interp *interp,
ExprInfo *infoPtr, int flags,
CompileEnv *envPtr));
static int CompileMultiplyExpr _ANSI_ARGS_((Tcl_Interp *interp,
ExprInfo *infoPtr, int flags,
CompileEnv *envPtr));
static int CompilePrimaryExpr _ANSI_ARGS_((Tcl_Interp *interp,
ExprInfo *infoPtr, int flags,
CompileEnv *envPtr));
static int CompileRelationalExpr _ANSI_ARGS_((
Tcl_Interp *interp, ExprInfo *infoPtr,
int flags, CompileEnv *envPtr));
static int CompileShiftExpr _ANSI_ARGS_((Tcl_Interp *interp,
ExprInfo *infoPtr, int flags,
CompileEnv *envPtr));
static int CompileUnaryExpr _ANSI_ARGS_((Tcl_Interp *interp,
ExprInfo *infoPtr, int flags,
CompileEnv *envPtr));
static int GetToken _ANSI_ARGS_((Tcl_Interp *interp,
ExprInfo *infoPtr, CompileEnv *envPtr));
/*
* Macro used to debug the execution of the recursive descent parser used
* to compile expressions.
*/
#ifdef TCL_COMPILE_DEBUG
#define HERE(production, level) \
if (traceCompileExpr) { \
fprintf(stderr, "%*s%s: token=%s, next=\"%.20s\"\n", \
(level), " ", (production), tokenStrings[infoPtr->token], \
infoPtr->next); \
}
#else
#define HERE(production, level)
#endif /* TCL_COMPILE_DEBUG */
/*
*----------------------------------------------------------------------
*
* TclCompileExpr --
*
* This procedure compiles a string containing a Tcl expression into
* Tcl bytecodes. This procedure is the top-level interface to the
* the expression compilation module, and is used by such public
* procedures as Tcl_ExprString, Tcl_ExprStringObj, Tcl_ExprLong,
* Tcl_ExprDouble, Tcl_ExprBoolean, and Tcl_ExprBooleanObj.
*
* Note that the topmost recursive-descent parsing routine used by
* TclCompileExpr to compile expressions is called "CompileCondExpr"
* and not, e.g., "CompileExpr". This is done to avoid an extra
* procedure call since such a procedure would only return the result
* of calling CompileCondExpr. Other recursive-descent procedures
* that need to parse expressions also call CompileCondExpr.
*
* Results:
* The return value is TCL_OK on a successful compilation and TCL_ERROR
* on failure. If TCL_ERROR is returned, then the interpreter's result
* contains an error message.
*
* envPtr->termOffset is filled in with the offset of the character in
* "string" just after the last one successfully processed; this might
* be the offset of the ']' (if flags & TCL_BRACKET_TERM), or the
* offset of the '\0' at the end of the string.
*
* envPtr->maxStackDepth is updated with the maximum number of stack
* elements needed to execute the expression.
*
* envPtr->exprIsJustVarRef is set 1 if the expression consisted of
* a single variable reference as in the expression of "if $b then...".
* Otherwise it is set 0. This is used to implement Tcl's two level
* expression substitution semantics properly.
*
* envPtr->exprIsComparison is set 1 if the top-level operator in the
* expr is a comparison. Otherwise it is set 0. If 1, because the
* operands might be strings, the expr is compiled out-of-line in order
* to implement expr's 2 level substitution semantics properly.
*
* Side effects:
* Adds instructions to envPtr to evaluate the expression at runtime.
*
*----------------------------------------------------------------------
*/
int
TclCompileExpr(interp, string, lastChar, flags, envPtr)
Tcl_Interp *interp; /* Used for error reporting. */
char *string; /* The source string to compile. */
char *lastChar; /* Pointer to terminating character of
* string. */
int flags; /* Flags to control compilation (same as
* passed to Tcl_Eval). */
CompileEnv *envPtr; /* Holds resulting instructions. */
{
Interp *iPtr = (Interp *) interp;
ExprInfo info;
int maxDepth = 0; /* Maximum number of stack elements needed
* to execute the expression. */
int result;
#ifdef TCL_COMPILE_DEBUG
if (traceCompileExpr) {
fprintf(stderr, "expr: string=\"%.30s\"\n", string);
}
#endif /* TCL_COMPILE_DEBUG */
/*
* Register the builtin math functions the first time an expression is
* compiled.
*/
if (!(iPtr->flags & EXPR_INITIALIZED)) {
BuiltinFunc *funcPtr;
Tcl_HashEntry *hPtr;
MathFunc *mathFuncPtr;
int i;
iPtr->flags |= EXPR_INITIALIZED;
i = 0;
for (funcPtr = builtinFuncTable; funcPtr->name != NULL; funcPtr++) {
Tcl_CreateMathFunc(interp, funcPtr->name,
funcPtr->numArgs, funcPtr->argTypes,
(Tcl_MathProc *) NULL, (ClientData) 0);
hPtr = Tcl_FindHashEntry(&iPtr->mathFuncTable, funcPtr->name);
if (hPtr == NULL) {
panic("TclCompileExpr: Tcl_CreateMathFunc incorrectly registered '%s'", funcPtr->name);
return TCL_ERROR;
}
mathFuncPtr = (MathFunc *) Tcl_GetHashValue(hPtr);
mathFuncPtr->builtinFuncIndex = i;
i++;
}
}
info.token = UNKNOWN;
info.objIndex = -1;
info.funcName = NULL;
info.next = string;
info.originalExpr = string;
info.lastChar = lastChar;
info.hasOperators = 0;
info.exprIsJustVarRef = 1; /* will be set 0 if anything else is seen */
info.exprIsComparison = 0; /* set 1 if topmost operator is <,==,etc. */
/*
* Get the first token then compile an expression.
*/
result = GetToken(interp, &info, envPtr);
if (result != TCL_OK) {
goto done;
}
result = CompileCondExpr(interp, &info, flags, envPtr);
if (result != TCL_OK) {
goto done;
}
if (info.token != END) {
Tcl_AppendStringsToObj(Tcl_GetObjResult(interp),
"syntax error in expression \"", string, "\"", (char *) NULL);
result = TCL_ERROR;
goto done;
}
if (!info.hasOperators) {
/*
* Attempt to convert the primary's object to an int or double.
* This is done in order to support Tcl's policy of interpreting
* operands if at all possible as first integers, else
* floating-point numbers.
*/
TclEmitOpcode(INST_TRY_CVT_TO_NUMERIC, envPtr);
}
maxDepth = envPtr->maxStackDepth;
done:
envPtr->termOffset = (info.next - string);
envPtr->maxStackDepth = maxDepth;
envPtr->exprIsJustVarRef = info.exprIsJustVarRef;
envPtr->exprIsComparison = info.exprIsComparison;
return result;
}
/*
*----------------------------------------------------------------------
*
* CompileCondExpr --
*
* This procedure compiles a Tcl conditional expression:
* condExpr ::= lorExpr ['?' condExpr ':' condExpr]
*
* Note that this is the topmost recursive-descent parsing routine used
* by TclCompileExpr to compile expressions. It does not call an
* separate, higher-level "CompileExpr" procedure. This avoids an extra
* procedure call since such a procedure would only return the result
* of calling CompileCondExpr. Other recursive-descent procedures that
* need to parse expressions also call CompileCondExpr.
*
* Results:
* The return value is TCL_OK on a successful compilation and TCL_ERROR
* on failure. If TCL_ERROR is returned, then the interpreter's result
* contains an error message.
*
* envPtr->maxStackDepth is updated with the maximum number of stack
* elements needed to execute the expression.
*
* Side effects:
* Adds instructions to envPtr to evaluate the expression at runtime.
*
*----------------------------------------------------------------------
*/
static int
CompileCondExpr(interp, infoPtr, flags, envPtr)
Tcl_Interp *interp; /* Used for error reporting. */
ExprInfo *infoPtr; /* Describes the compilation state for the
* expression being compiled. */
int flags; /* Flags to control compilation (same as
* passed to Tcl_Eval). */
CompileEnv *envPtr; /* Holds resulting instructions. */
{
int maxDepth = 0; /* Maximum number of stack elements needed
* to execute the expression. */
JumpFixup jumpAroundThenFixup, jumpAroundElseFixup;
/* Used to update or replace one-byte jumps
* around the then and else expressions when
* their target PCs are determined. */
int elseCodeOffset, currCodeOffset, jumpDist, result;
HERE("condExpr", 1);
result = CompileLorExpr(interp, infoPtr, flags, envPtr);
if (result != TCL_OK) {
goto done;
}
maxDepth = envPtr->maxStackDepth;
if (infoPtr->token == QUESTY) {
result = GetToken(interp, infoPtr, envPtr); /* skip over the '?' */
if (result != TCL_OK) {
goto done;
}
/*
* Emit the jump around the "then" clause to the "else" condExpr if
* the test was false. We emit a one byte (relative) jump here, and
* replace it later with a four byte jump if the jump target is more
* than 127 bytes away.
*/
TclEmitForwardJump(envPtr, TCL_FALSE_JUMP, &jumpAroundThenFixup);
/*
* Compile the "then" expression. Note that if a subexpression
* is only a primary, we need to try to convert it to numeric.
* This is done in order to support Tcl's policy of interpreting
* operands if at all possible as first integers, else
* floating-point numbers.
*/
infoPtr->hasOperators = 0;
infoPtr->exprIsJustVarRef = 0;
infoPtr->exprIsComparison = 0;
result = CompileCondExpr(interp, infoPtr, flags, envPtr);
if (result != TCL_OK) {
goto done;
}
maxDepth = TclMax(envPtr->maxStackDepth, maxDepth);
if (infoPtr->token != COLON) {
Tcl_AppendStringsToObj(Tcl_GetObjResult(interp),
"syntax error in expression \"", infoPtr->originalExpr,
"\"", (char *) NULL);
result = TCL_ERROR;
goto done;
}
if (!infoPtr->hasOperators) {
TclEmitOpcode(INST_TRY_CVT_TO_NUMERIC, envPtr);
}
result = GetToken(interp, infoPtr, envPtr); /* skip over the ':' */
if (result != TCL_OK) {
goto done;
}
/*
* Emit an unconditional jump around the "else" condExpr.
*/
TclEmitForwardJump(envPtr, TCL_UNCONDITIONAL_JUMP,
&jumpAroundElseFixup);
/*
* Compile the "else" expression.
*/
infoPtr->hasOperators = 0;
elseCodeOffset = TclCurrCodeOffset();
result = CompileCondExpr(interp, infoPtr, flags, envPtr);
if (result != TCL_OK) {
goto done;
}
maxDepth = TclMax(envPtr->maxStackDepth, maxDepth);
if (!infoPtr->hasOperators) {
TclEmitOpcode(INST_TRY_CVT_TO_NUMERIC, envPtr);
}
/*
* Fix up the second jump: the unconditional jump around the "else"
* expression. If the distance is too great (> 127 bytes), replace
* it with a four byte instruction and move the instructions after
* the jump down.
*/
currCodeOffset = TclCurrCodeOffset();
jumpDist = (currCodeOffset - jumpAroundElseFixup.codeOffset);
if (TclFixupForwardJump(envPtr, &jumpAroundElseFixup, jumpDist, 127)) {
/*
* Update the else expression's starting code offset since it
* moved down 3 bytes too.
*/
elseCodeOffset += 3;
}
/*
* Now fix up the first branch: the jumpFalse after the test. If the
* distance is too great, replace it with a four byte instruction
* and update the code offsets for the commands in both the "then"
* and "else" expressions.
*/
jumpDist = (elseCodeOffset - jumpAroundThenFixup.codeOffset);
TclFixupForwardJump(envPtr, &jumpAroundThenFixup, jumpDist, 127);
infoPtr->hasOperators = 1;
/*
* A comparison is not the top-level operator in this expression.
*/
infoPtr->exprIsComparison = 0;
}
done:
envPtr->maxStackDepth = maxDepth;
return result;
}
/*
*----------------------------------------------------------------------
*
* CompileLorExpr --
*
* This procedure compiles a Tcl logical or expression:
* lorExpr ::= landExpr {'||' landExpr}
*
* Results:
* The return value is TCL_OK on a successful compilation and TCL_ERROR
* on failure. If TCL_ERROR is returned, then the interpreter's result
* contains an error message.
*
* envPtr->maxStackDepth is updated with the maximum number of stack
* elements needed to execute the expression.
*
* Side effects:
* Adds instructions to envPtr to evaluate the expression at runtime.
*
*----------------------------------------------------------------------
*/
static int
CompileLorExpr(interp, infoPtr, flags, envPtr)
Tcl_Interp *interp; /* Used for error reporting. */
ExprInfo *infoPtr; /* Describes the compilation state for the
* expression being compiled. */
int flags; /* Flags to control compilation (same as
* passed to Tcl_Eval). */
CompileEnv *envPtr; /* Holds resulting instructions. */
{
int maxDepth; /* Maximum number of stack elements needed
* to execute the expression. */
JumpFixupArray jumpFixupArray;
/* Used to fix up the forward "short
* circuit" jump after each or-ed
* subexpression to just after the last
* subexpression. */
JumpFixup jumpTrueFixup, jumpFixup;
/* Used to emit the jumps in the code to
* convert the first operand to a 0 or 1. */
int fixupIndex, jumpDist, currCodeOffset, objIndex, j, result;
Tcl_Obj *objPtr;
HERE("lorExpr", 2);
result = CompileLandExpr(interp, infoPtr, flags, envPtr);
if ((result != TCL_OK) || (infoPtr->token != OR)) {
return result; /* envPtr->maxStackDepth is already set */
}
infoPtr->hasOperators = 1;
infoPtr->exprIsJustVarRef = 0;
maxDepth = envPtr->maxStackDepth;
TclInitJumpFixupArray(&jumpFixupArray);
while (infoPtr->token == OR) {
result = GetToken(interp, infoPtr, envPtr); /* skip over the '||' */
if (result != TCL_OK) {
goto done;
}
if (jumpFixupArray.next == 0) {
/*
* Just the first "lor" operand is on the stack. The following
* is slightly ugly: we need to convert that first "lor" operand
* to a "0" or "1" to get the correct result if it is nonzero.
* Eventually we'll use a new instruction for this.
*/
TclEmitForwardJump(envPtr, TCL_TRUE_JUMP, &jumpTrueFixup);
objIndex = TclObjIndexForString("0", 1, /*allocStrRep*/ 0,
/*inHeap*/ 0, envPtr);
objPtr = envPtr->objArrayPtr[objIndex];
Tcl_InvalidateStringRep(objPtr);
objPtr->internalRep.longValue = 0;
objPtr->typePtr = &tclIntType;
TclEmitPush(objIndex, envPtr);
TclEmitForwardJump(envPtr, TCL_UNCONDITIONAL_JUMP, &jumpFixup);
jumpDist = (TclCurrCodeOffset() - jumpTrueFixup.codeOffset);
if (TclFixupForwardJump(envPtr, &jumpTrueFixup, jumpDist, 127)) {
panic("CompileLorExpr: bad jump distance %d\n", jumpDist);
}
objIndex = TclObjIndexForString("1", 1, /*allocStrRep*/ 0,
/*inHeap*/ 0, envPtr);
objPtr = envPtr->objArrayPtr[objIndex];
Tcl_InvalidateStringRep(objPtr);
objPtr->internalRep.longValue = 1;
objPtr->typePtr = &tclIntType;
TclEmitPush(objIndex, envPtr);
jumpDist = (TclCurrCodeOffset() - jumpFixup.codeOffset);
if (TclFixupForwardJump(envPtr, &jumpFixup, jumpDist, 127)) {
panic("CompileLorExpr: bad jump distance %d\n", jumpDist);
}
}
/*
* Duplicate the value on top of the stack to prevent the jump from
* consuming it.
*/
TclEmitOpcode(INST_DUP, envPtr);
/*
* Emit the "short circuit" jump around the rest of the lorExp if
* the previous expression was true. We emit a one byte (relative)
* jump here, and replace it later with a four byte jump if the jump
* target is more than 127 bytes away.
*/
if (jumpFixupArray.next == jumpFixupArray.end) {
TclExpandJumpFixupArray(&jumpFixupArray);
}
fixupIndex = jumpFixupArray.next;
jumpFixupArray.next++;
TclEmitForwardJump(envPtr, TCL_TRUE_JUMP,
&(jumpFixupArray.fixup[fixupIndex]));
/*
* Compile the subexpression.
*/
result = CompileLandExpr(interp, infoPtr, flags, envPtr);
if (result != TCL_OK) {
goto done;
}
maxDepth = TclMax((envPtr->maxStackDepth + 1), maxDepth);
/*
* Emit a "logical or" instruction. This does not try to "short-
* circuit" the evaluation of both operands of a Tcl "||" operator,
* but instead ensures that we either have a "1" or a "0" result.
*/
TclEmitOpcode(INST_LOR, envPtr);
}
/*
* Now that we know the target of the forward jumps, update the jumps
* with the correct distance. Also, if the distance is too great (> 127
* bytes), replace the jump with a four byte instruction and move the
* instructions after the jump down.
*/
for (j = jumpFixupArray.next; j > 0; j--) {
fixupIndex = (j - 1); /* process closest jump first */
currCodeOffset = TclCurrCodeOffset();
jumpDist = (currCodeOffset - jumpFixupArray.fixup[fixupIndex].codeOffset);
TclFixupForwardJump(envPtr, &(jumpFixupArray.fixup[fixupIndex]), jumpDist, 127);
}
/*
* We get here only if one or more ||'s appear as top-level operators.
*/
done:
infoPtr->exprIsComparison = 0;
TclFreeJumpFixupArray(&jumpFixupArray);
envPtr->maxStackDepth = maxDepth;
return result;
}
/*
*----------------------------------------------------------------------
*
* CompileLandExpr --
*
* This procedure compiles a Tcl logical and expression:
* landExpr ::= bitOrExpr {'&&' bitOrExpr}
*
* Results:
* The return value is TCL_OK on a successful compilation and TCL_ERROR
* on failure. If TCL_ERROR is returned, then the interpreter's result
* contains an error message.
*
* envPtr->maxStackDepth is updated with the maximum number of stack
* elements needed to execute the expression.
*
* Side effects:
* Adds instructions to envPtr to evaluate the expression at runtime.
*
*----------------------------------------------------------------------
*/
static int
CompileLandExpr(interp, infoPtr, flags, envPtr)
Tcl_Interp *interp; /* Used for error reporting. */
ExprInfo *infoPtr; /* Describes the compilation state for the
* expression being compiled. */
int flags; /* Flags to control compilation (same as
* passed to Tcl_Eval). */
CompileEnv *envPtr; /* Holds resulting instructions. */
{
int maxDepth; /* Maximum number of stack elements needed
* to execute the expression. */
JumpFixupArray jumpFixupArray;
/* Used to fix up the forward "short
* circuit" jump after each and-ed
* subexpression to just after the last
* subexpression. */
JumpFixup jumpTrueFixup, jumpFixup;
/* Used to emit the jumps in the code to
* convert the first operand to a 0 or 1. */
int fixupIndex, jumpDist, currCodeOffset, objIndex, j, result;
Tcl_Obj *objPtr;
HERE("landExpr", 3);
result = CompileBitOrExpr(interp, infoPtr, flags, envPtr);
if ((result != TCL_OK) || (infoPtr->token != AND)) {
return result; /* envPtr->maxStackDepth is already set */
}
infoPtr->hasOperators = 1;
infoPtr->exprIsJustVarRef = 0;
maxDepth = envPtr->maxStackDepth;
TclInitJumpFixupArray(&jumpFixupArray);
while (infoPtr->token == AND) {
result = GetToken(interp, infoPtr, envPtr); /* skip over the '&&' */
if (result != TCL_OK) {
goto done;
}
if (jumpFixupArray.next == 0) {
/*
* Just the first "land" operand is on the stack. The following
* is slightly ugly: we need to convert the first "land" operand
* to a "0" or "1" to get the correct result if it is
* nonzero. Eventually we'll use a new instruction.
*/
TclEmitForwardJump(envPtr, TCL_TRUE_JUMP, &jumpTrueFixup);
objIndex = TclObjIndexForString("0", 1, /*allocStrRep*/ 0,
/*inHeap*/ 0, envPtr);
objPtr = envPtr->objArrayPtr[objIndex];
Tcl_InvalidateStringRep(objPtr);
objPtr->internalRep.longValue = 0;
objPtr->typePtr = &tclIntType;
TclEmitPush(objIndex, envPtr);
TclEmitForwardJump(envPtr, TCL_UNCONDITIONAL_JUMP, &jumpFixup);
jumpDist = (TclCurrCodeOffset() - jumpTrueFixup.codeOffset);
if (TclFixupForwardJump(envPtr, &jumpTrueFixup, jumpDist, 127)) {
panic("CompileLandExpr: bad jump distance %d\n", jumpDist);
}
objIndex = TclObjIndexForString("1", 1, /*allocStrRep*/ 0,
/*inHeap*/ 0, envPtr);
objPtr = envPtr->objArrayPtr[objIndex];
Tcl_InvalidateStringRep(objPtr);
objPtr->internalRep.longValue = 1;
objPtr->typePtr = &tclIntType;
TclEmitPush(objIndex, envPtr);
jumpDist = (TclCurrCodeOffset() - jumpFixup.codeOffset);
if (TclFixupForwardJump(envPtr, &jumpFixup, jumpDist, 127)) {
panic("CompileLandExpr: bad jump distance %d\n", jumpDist);
}
}
/*
* Duplicate the value on top of the stack to prevent the jump from
* consuming it.
*/
TclEmitOpcode(INST_DUP, envPtr);
/*
* Emit the "short circuit" jump around the rest of the landExp if
* the previous expression was false. We emit a one byte (relative)
* jump here, and replace it later with a four byte jump if the jump
* target is more than 127 bytes away.
*/
if (jumpFixupArray.next == jumpFixupArray.end) {
TclExpandJumpFixupArray(&jumpFixupArray);
}
fixupIndex = jumpFixupArray.next;
jumpFixupArray.next++;
TclEmitForwardJump(envPtr, TCL_FALSE_JUMP,
&(jumpFixupArray.fixup[fixupIndex]));
/*
* Compile the subexpression.
*/
result = CompileBitOrExpr(interp, infoPtr, flags, envPtr);
if (result != TCL_OK) {
goto done;
}
maxDepth = TclMax((envPtr->maxStackDepth + 1), maxDepth);
/*
* Emit a "logical and" instruction. This does not try to "short-
* circuit" the evaluation of both operands of a Tcl "&&" operator,
* but instead ensures that we either have a "1" or a "0" result.
*/
TclEmitOpcode(INST_LAND, envPtr);
}
/*
* Now that we know the target of the forward jumps, update the jumps
* with the correct distance. Also, if the distance is too great (> 127
* bytes), replace the jump with a four byte instruction and move the
* instructions after the jump down.
*/
for (j = jumpFixupArray.next; j > 0; j--) {
fixupIndex = (j - 1); /* process closest jump first */
currCodeOffset = TclCurrCodeOffset();
jumpDist = (currCodeOffset - jumpFixupArray.fixup[fixupIndex].codeOffset);
TclFixupForwardJump(envPtr, &(jumpFixupArray.fixup[fixupIndex]),
jumpDist, 127);
}
/*
* We get here only if one or more &&'s appear as top-level operators.
*/
done:
infoPtr->exprIsComparison = 0;
TclFreeJumpFixupArray(&jumpFixupArray);
envPtr->maxStackDepth = maxDepth;
return result;
}
/*
*----------------------------------------------------------------------
*
* CompileBitOrExpr --
*
* This procedure compiles a Tcl bitwise or expression:
* bitOrExpr ::= bitXorExpr {'|' bitXorExpr}
*
* Results:
* The return value is TCL_OK on a successful compilation and TCL_ERROR
* on failure. If TCL_ERROR is returned, then the interpreter's result
* contains an error message.
*
* envPtr->maxStackDepth is updated with the maximum number of stack
* elements needed to execute the expression.
*
* Side effects:
* Adds instructions to envPtr to evaluate the expression at runtime.
*
*----------------------------------------------------------------------
*/
static int
CompileBitOrExpr(interp, infoPtr, flags, envPtr)
Tcl_Interp *interp; /* Used for error reporting. */
ExprInfo *infoPtr; /* Describes the compilation state for the
* expression being compiled. */
int flags; /* Flags to control compilation (same as
* passed to Tcl_Eval). */
CompileEnv *envPtr; /* Holds resulting instructions. */
{
int maxDepth = 0; /* Maximum number of stack elements needed
* to execute the expression. */
int result;
HERE("bitOrExpr", 4);
result = CompileBitXorExpr(interp, infoPtr, flags, envPtr);
if (result != TCL_OK) {
goto done;
}
maxDepth = envPtr->maxStackDepth;
while (infoPtr->token == BIT_OR) {
infoPtr->hasOperators = 1;
infoPtr->exprIsJustVarRef = 0;
result = GetToken(interp, infoPtr, envPtr); /* skip over the '|' */
if (result != TCL_OK) {
goto done;
}
result = CompileBitXorExpr(interp, infoPtr, flags, envPtr);
if (result != TCL_OK) {
goto done;
}
maxDepth = TclMax((envPtr->maxStackDepth + 1), maxDepth);
TclEmitOpcode(INST_BITOR, envPtr);
/*
* A comparison is not the top-level operator in this expression.
*/
infoPtr->exprIsComparison = 0;
}
done:
envPtr->maxStackDepth = maxDepth;
return result;
}
/*
*----------------------------------------------------------------------
*
* CompileBitXorExpr --
*
* This procedure compiles a Tcl bitwise exclusive or expression:
* bitXorExpr ::= bitAndExpr {'^' bitAndExpr}
*
* Results:
* The return value is TCL_OK on a successful compilation and TCL_ERROR
* on failure. If TCL_ERROR is returned, then the interpreter's result
* contains an error message.
*
* envPtr->maxStackDepth is updated with the maximum number of stack
* elements needed to execute the expression.
*
* Side effects:
* Adds instructions to envPtr to evaluate the expression at runtime.
*
*----------------------------------------------------------------------
*/
static int
CompileBitXorExpr(interp, infoPtr, flags, envPtr)
Tcl_Interp *interp; /* Used for error reporting. */
ExprInfo *infoPtr; /* Describes the compilation state for the
* expression being compiled. */
int flags; /* Flags to control compilation (same as
* passed to Tcl_Eval). */
CompileEnv *envPtr; /* Holds resulting instructions. */
{
int maxDepth = 0; /* Maximum number of stack elements needed
* to execute the expression. */
int result;
HERE("bitXorExpr", 5);
result = CompileBitAndExpr(interp, infoPtr, flags, envPtr);
if (result != TCL_OK) {
goto done;
}
maxDepth = envPtr->maxStackDepth;
while (infoPtr->token == BIT_XOR) {
infoPtr->hasOperators = 1;
infoPtr->exprIsJustVarRef = 0;
result = GetToken(interp, infoPtr, envPtr); /* skip over the '^' */
if (result != TCL_OK) {
goto done;
}
result = CompileBitAndExpr(interp, infoPtr, flags, envPtr);
if (result != TCL_OK) {
goto done;
}
maxDepth = TclMax((envPtr->maxStackDepth + 1), maxDepth);
TclEmitOpcode(INST_BITXOR, envPtr);
/*
* A comparison is not the top-level operator in this expression.
*/
infoPtr->exprIsComparison = 0;
}
done:
envPtr->maxStackDepth = maxDepth;
return result;
}
/*
*----------------------------------------------------------------------
*
* CompileBitAndExpr --
*
* This procedure compiles a Tcl bitwise and expression:
* bitAndExpr ::= equalityExpr {'&' equalityExpr}
*
* Results:
* The return value is TCL_OK on a successful compilation and TCL_ERROR
* on failure. If TCL_ERROR is returned, then the interpreter's result
* contains an error message.
*
* envPtr->maxStackDepth is updated with the maximum number of stack
* elements needed to execute the expression.
*
* Side effects:
* Adds instructions to envPtr to evaluate the expression at runtime.
*
*----------------------------------------------------------------------
*/
static int
CompileBitAndExpr(interp, infoPtr, flags, envPtr)
Tcl_Interp *interp; /* Used for error reporting. */
ExprInfo *infoPtr; /* Describes the compilation state for the
* expression being compiled. */
int flags; /* Flags to control compilation (same as
* passed to Tcl_Eval). */
CompileEnv *envPtr; /* Holds resulting instructions. */
{
int maxDepth = 0; /* Maximum number of stack elements needed
* to execute the expression. */
int result;
HERE("bitAndExpr", 6);
result = CompileEqualityExpr(interp, infoPtr, flags, envPtr);
if (result != TCL_OK) {
goto done;
}
maxDepth = envPtr->maxStackDepth;
while (infoPtr->token == BIT_AND) {
infoPtr->hasOperators = 1;
infoPtr->exprIsJustVarRef = 0;
result = GetToken(interp, infoPtr, envPtr); /* skip over the '&' */
if (result != TCL_OK) {
goto done;
}
result = CompileEqualityExpr(interp, infoPtr, flags, envPtr);
if (result != TCL_OK) {
goto done;
}
maxDepth = TclMax((envPtr->maxStackDepth + 1), maxDepth);
TclEmitOpcode(INST_BITAND, envPtr);
/*
* A comparison is not the top-level operator in this expression.
*/
infoPtr->exprIsComparison = 0;
}
done:
envPtr->maxStackDepth = maxDepth;
return result;
}
/*
*----------------------------------------------------------------------
*
* CompileEqualityExpr --
*
* This procedure compiles a Tcl equality (inequality) expression:
* equalityExpr ::= relationalExpr {('==' | '!=') relationalExpr}
*
* Results:
* The return value is TCL_OK on a successful compilation and TCL_ERROR
* on failure. If TCL_ERROR is returned, then the interpreter's result
* contains an error message.
*
* envPtr->maxStackDepth is updated with the maximum number of stack
* elements needed to execute the expression.
*
* Side effects:
* Adds instructions to envPtr to evaluate the expression at runtime.
*
*----------------------------------------------------------------------
*/
static int
CompileEqualityExpr(interp, infoPtr, flags, envPtr)
Tcl_Interp *interp; /* Used for error reporting. */
ExprInfo *infoPtr; /* Describes the compilation state for the
* expression being compiled. */
int flags; /* Flags to control compilation (same as
* passed to Tcl_Eval). */
CompileEnv *envPtr; /* Holds resulting instructions. */
{
int maxDepth = 0; /* Maximum number of stack elements needed
* to execute the expression. */
int op, result;
HERE("equalityExpr", 7);
result = CompileRelationalExpr(interp, infoPtr, flags, envPtr);
if (result != TCL_OK) {
goto done;
}
maxDepth = envPtr->maxStackDepth;
op = infoPtr->token;
while ((op == EQUAL) || (op == NEQ)) {
infoPtr->hasOperators = 1;
infoPtr->exprIsJustVarRef = 0;
result = GetToken(interp, infoPtr, envPtr); /* skip over == or != */
if (result != TCL_OK) {
goto done;
}
result = CompileRelationalExpr(interp, infoPtr, flags, envPtr);
if (result != TCL_OK) {
goto done;
}
maxDepth = TclMax((envPtr->maxStackDepth + 1), maxDepth);
if (op == EQUAL) {
TclEmitOpcode(INST_EQ, envPtr);
} else {
TclEmitOpcode(INST_NEQ, envPtr);
}
op = infoPtr->token;
/*
* A comparison _is_ the top-level operator in this expression.
*/
infoPtr->exprIsComparison = 1;
}
done:
envPtr->maxStackDepth = maxDepth;
return result;
}
/*
*----------------------------------------------------------------------
*
* CompileRelationalExpr --
*
* This procedure compiles a Tcl relational expression:
* relationalExpr ::= shiftExpr {('<' | '>' | '<=' | '>=') shiftExpr}
*
* Results:
* The return value is TCL_OK on a successful compilation and TCL_ERROR
* on failure. If TCL_ERROR is returned, then the interpreter's result
* contains an error message.
*
* envPtr->maxStackDepth is updated with the maximum number of stack
* elements needed to execute the expression.
*
* Side effects:
* Adds instructions to envPtr to evaluate the expression at runtime.
*
*----------------------------------------------------------------------
*/
static int
CompileRelationalExpr(interp, infoPtr, flags, envPtr)
Tcl_Interp *interp; /* Used for error reporting. */
ExprInfo *infoPtr; /* Describes the compilation state for the
* expression being compiled. */
int flags; /* Flags to control compilation (same as
* passed to Tcl_Eval). */
CompileEnv *envPtr; /* Holds resulting instructions. */
{
int maxDepth = 0; /* Maximum number of stack elements needed
* to execute the expression. */
int op, result;
HERE("relationalExpr", 8);
result = CompileShiftExpr(interp, infoPtr, flags, envPtr);
if (result != TCL_OK) {
goto done;
}
maxDepth = envPtr->maxStackDepth;
op = infoPtr->token;
while ((op == LESS) || (op == GREATER) || (op == LEQ) || (op == GEQ)) {
infoPtr->hasOperators = 1;
infoPtr->exprIsJustVarRef = 0;
result = GetToken(interp, infoPtr, envPtr); /* skip over the op */
if (result != TCL_OK) {
goto done;
}
result = CompileShiftExpr(interp, infoPtr, flags, envPtr);
if (result != TCL_OK) {
goto done;
}
maxDepth = TclMax((envPtr->maxStackDepth + 1), maxDepth);
switch (op) {
case LESS:
TclEmitOpcode(INST_LT, envPtr);
break;
case GREATER:
TclEmitOpcode(INST_GT, envPtr);
break;
case LEQ:
TclEmitOpcode(INST_LE, envPtr);
break;
case GEQ:
TclEmitOpcode(INST_GE, envPtr);
break;
}
op = infoPtr->token;
/*
* A comparison _is_ the top-level operator in this expression.
*/
infoPtr->exprIsComparison = 1;
}
done:
envPtr->maxStackDepth = maxDepth;
return result;
}
/*
*----------------------------------------------------------------------
*
* CompileShiftExpr --
*
* This procedure compiles a Tcl shift expression:
* shiftExpr ::= addExpr {('<<' | '>>') addExpr}
*
* Results:
* The return value is TCL_OK on a successful compilation and TCL_ERROR
* on failure. If TCL_ERROR is returned, then the interpreter's result
* contains an error message.
*
* envPtr->maxStackDepth is updated with the maximum number of stack
* elements needed to execute the expression.
*
* Side effects:
* Adds instructions to envPtr to evaluate the expression at runtime.
*
*----------------------------------------------------------------------
*/
static int
CompileShiftExpr(interp, infoPtr, flags, envPtr)
Tcl_Interp *interp; /* Used for error reporting. */
ExprInfo *infoPtr; /* Describes the compilation state for the
* expression being compiled. */
int flags; /* Flags to control compilation (same as
* passed to Tcl_Eval). */
CompileEnv *envPtr; /* Holds resulting instructions. */
{
int maxDepth = 0; /* Maximum number of stack elements needed
* to execute the expression. */
int op, result;
HERE("shiftExpr", 9);
result = CompileAddExpr(interp, infoPtr, flags, envPtr);
if (result != TCL_OK) {
goto done;
}
maxDepth = envPtr->maxStackDepth;
op = infoPtr->token;
while ((op == LEFT_SHIFT) || (op == RIGHT_SHIFT)) {
infoPtr->hasOperators = 1;
infoPtr->exprIsJustVarRef = 0;
result = GetToken(interp, infoPtr, envPtr); /* skip over << or >> */
if (result != TCL_OK) {
goto done;
}
result = CompileAddExpr(interp, infoPtr, flags, envPtr);
if (result != TCL_OK) {
goto done;
}
maxDepth = TclMax((envPtr->maxStackDepth + 1), maxDepth);
if (op == LEFT_SHIFT) {
TclEmitOpcode(INST_LSHIFT, envPtr);
} else {
TclEmitOpcode(INST_RSHIFT, envPtr);
}
op = infoPtr->token;
/*
* A comparison is not the top-level operator in this expression.
*/
infoPtr->exprIsComparison = 0;
}
done:
envPtr->maxStackDepth = maxDepth;
return result;
}
/*
*----------------------------------------------------------------------
*
* CompileAddExpr --
*
* This procedure compiles a Tcl addition expression:
* addExpr ::= multiplyExpr {('+' | '-') multiplyExpr}
*
* Results:
* The return value is TCL_OK on a successful compilation and TCL_ERROR
* on failure. If TCL_ERROR is returned, then the interpreter's result
* contains an error message.
*
* envPtr->maxStackDepth is updated with the maximum number of stack
* elements needed to execute the expression.
*
* Side effects:
* Adds instructions to envPtr to evaluate the expression at runtime.
*
*----------------------------------------------------------------------
*/
static int
CompileAddExpr(interp, infoPtr, flags, envPtr)
Tcl_Interp *interp; /* Used for error reporting. */
ExprInfo *infoPtr; /* Describes the compilation state for the
* expression being compiled. */
int flags; /* Flags to control compilation (same as
* passed to Tcl_Eval). */
CompileEnv *envPtr; /* Holds resulting instructions. */
{
int maxDepth = 0; /* Maximum number of stack elements needed
* to execute the expression. */
int op, result;
HERE("addExpr", 10);
result = CompileMultiplyExpr(interp, infoPtr, flags, envPtr);
if (result != TCL_OK) {
goto done;
}
maxDepth = envPtr->maxStackDepth;
op = infoPtr->token;
while ((op == PLUS) || (op == MINUS)) {
infoPtr->hasOperators = 1;
infoPtr->exprIsJustVarRef = 0;
result = GetToken(interp, infoPtr, envPtr); /* skip over + or - */
if (result != TCL_OK) {
goto done;
}
result = CompileMultiplyExpr(interp, infoPtr, flags, envPtr);
if (result != TCL_OK) {
goto done;
}
maxDepth = TclMax((envPtr->maxStackDepth + 1), maxDepth);
if (op == PLUS) {
TclEmitOpcode(INST_ADD, envPtr);
} else {
TclEmitOpcode(INST_SUB, envPtr);
}
op = infoPtr->token;
/*
* A comparison is not the top-level operator in this expression.
*/
infoPtr->exprIsComparison = 0;
}
done:
envPtr->maxStackDepth = maxDepth;
return result;
}
/*
*----------------------------------------------------------------------
*
* CompileMultiplyExpr --
*
* This procedure compiles a Tcl multiply expression:
* multiplyExpr ::= unaryExpr {('*' | '/' | '%') unaryExpr}
*
* Results:
* The return value is TCL_OK on a successful compilation and TCL_ERROR
* on failure. If TCL_ERROR is returned, then the interpreter's result
* contains an error message.
*
* envPtr->maxStackDepth is updated with the maximum number of stack
* elements needed to execute the expression.
*
* Side effects:
* Adds instructions to envPtr to evaluate the expression at runtime.
*
*----------------------------------------------------------------------
*/
static int
CompileMultiplyExpr(interp, infoPtr, flags, envPtr)
Tcl_Interp *interp; /* Used for error reporting. */
ExprInfo *infoPtr; /* Describes the compilation state for the
* expression being compiled. */
int flags; /* Flags to control compilation (same as
* passed to Tcl_Eval). */
CompileEnv *envPtr; /* Holds resulting instructions. */
{
int maxDepth = 0; /* Maximum number of stack elements needed
* to execute the expression. */
int op, result;
HERE("multiplyExpr", 11);
result = CompileUnaryExpr(interp, infoPtr, flags, envPtr);
if (result != TCL_OK) {
goto done;
}
maxDepth = envPtr->maxStackDepth;
op = infoPtr->token;
while ((op == MULT) || (op == DIVIDE) || (op == MOD)) {
infoPtr->hasOperators = 1;
infoPtr->exprIsJustVarRef = 0;
result = GetToken(interp, infoPtr, envPtr); /* skip over * or / */
if (result != TCL_OK) {
goto done;
}
result = CompileUnaryExpr(interp, infoPtr, flags, envPtr);
if (result != TCL_OK) {
goto done;
}
maxDepth = TclMax((envPtr->maxStackDepth + 1), maxDepth);
if (op == MULT) {
TclEmitOpcode(INST_MULT, envPtr);
} else if (op == DIVIDE) {
TclEmitOpcode(INST_DIV, envPtr);
} else {
TclEmitOpcode(INST_MOD, envPtr);
}
op = infoPtr->token;
/*
* A comparison is not the top-level operator in this expression.
*/
infoPtr->exprIsComparison = 0;
}
done:
envPtr->maxStackDepth = maxDepth;
return result;
}
/*
*----------------------------------------------------------------------
*
* CompileUnaryExpr --
*
* This procedure compiles a Tcl unary expression:
* unaryExpr ::= ('+' | '-' | '~' | '!') unaryExpr | primaryExpr
*
* Results:
* The return value is TCL_OK on a successful compilation and TCL_ERROR
* on failure. If TCL_ERROR is returned, then the interpreter's result
* contains an error message.
*
* envPtr->maxStackDepth is updated with the maximum number of stack
* elements needed to execute the expression.
*
* Side effects:
* Adds instructions to envPtr to evaluate the expression at runtime.
*
*----------------------------------------------------------------------
*/
static int
CompileUnaryExpr(interp, infoPtr, flags, envPtr)
Tcl_Interp *interp; /* Used for error reporting. */
ExprInfo *infoPtr; /* Describes the compilation state for the
* expression being compiled. */
int flags; /* Flags to control compilation (same as
* passed to Tcl_Eval). */
CompileEnv *envPtr; /* Holds resulting instructions. */
{
int maxDepth = 0; /* Maximum number of stack elements needed
* to execute the expression. */
int op, result;
HERE("unaryExpr", 12);
op = infoPtr->token;
if ((op == PLUS) || (op == MINUS) || (op == BIT_NOT) || (op == NOT)) {
infoPtr->hasOperators = 1;
infoPtr->exprIsJustVarRef = 0;
result = GetToken(interp, infoPtr, envPtr); /* skip over the op */
if (result != TCL_OK) {
goto done;
}
result = CompileUnaryExpr(interp, infoPtr, flags, envPtr);
if (result != TCL_OK) {
goto done;
}
maxDepth = envPtr->maxStackDepth;
switch (op) {
case PLUS:
TclEmitOpcode(INST_UPLUS, envPtr);
break;
case MINUS:
TclEmitOpcode(INST_UMINUS, envPtr);
break;
case BIT_NOT:
TclEmitOpcode(INST_BITNOT, envPtr);
break;
case NOT:
TclEmitOpcode(INST_LNOT, envPtr);
break;
}
/*
* A comparison is not the top-level operator in this expression.
*/
infoPtr->exprIsComparison = 0;
} else { /* must be a primaryExpr */
result = CompilePrimaryExpr(interp, infoPtr, flags, envPtr);
if (result != TCL_OK) {
goto done;
}
maxDepth = envPtr->maxStackDepth;
}
done:
envPtr->maxStackDepth = maxDepth;
return result;
}
/*
*----------------------------------------------------------------------
*
* CompilePrimaryExpr --
*
* This procedure compiles a Tcl primary expression:
* primaryExpr ::= literal | varReference | quotedString |
* '[' command ']' | mathFuncCall | '(' condExpr ')'
*
* Results:
* The return value is TCL_OK on a successful compilation and TCL_ERROR
* on failure. If TCL_ERROR is returned, then the interpreter's result
* contains an error message.
*
* envPtr->maxStackDepth is updated with the maximum number of stack
* elements needed to execute the expression.
*
* Side effects:
* Adds instructions to envPtr to evaluate the expression at runtime.
*
*----------------------------------------------------------------------
*/
static int
CompilePrimaryExpr(interp, infoPtr, flags, envPtr)
Tcl_Interp *interp; /* Used for error reporting. */
ExprInfo *infoPtr; /* Describes the compilation state for the
* expression being compiled. */
int flags; /* Flags to control compilation (same as
* passed to Tcl_Eval). */
CompileEnv *envPtr; /* Holds resulting instructions. */
{
int maxDepth = 0; /* Maximum number of stack elements needed
* to execute the expression. */
int theToken;
char *dollarPtr, *quotePtr, *cmdPtr, *termPtr;
int result = TCL_OK;
/*
* We emit tryCvtToNumeric instructions after most of these primary
* expressions in order to support Tcl's policy of interpreting operands
* as first integers if possible, otherwise floating-point numbers if
* possible.
*/
HERE("primaryExpr", 13);
theToken = infoPtr->token;
if (theToken != DOLLAR) {
infoPtr->exprIsJustVarRef = 0;
}
switch (theToken) {
case LITERAL: /* int, double, or string in braces */
TclEmitPush(infoPtr->objIndex, envPtr);
maxDepth = 1;
break;
case DOLLAR: /* $var variable reference */
dollarPtr = (infoPtr->next - 1);
envPtr->pushSimpleWords = 1;
result = TclCompileDollarVar(interp, dollarPtr,
infoPtr->lastChar, flags, envPtr);
if (result != TCL_OK) {
goto done;
}
maxDepth = envPtr->maxStackDepth;
infoPtr->next = (dollarPtr + envPtr->termOffset);
break;
case QUOTE: /* quotedString */
quotePtr = infoPtr->next;
envPtr->pushSimpleWords = 1;
result = TclCompileQuotes(interp, quotePtr,
infoPtr->lastChar, '"', flags, envPtr);
if (result != TCL_OK) {
goto done;
}
maxDepth = envPtr->maxStackDepth;
infoPtr->next = (quotePtr + envPtr->termOffset);
break;
case OPEN_BRACKET: /* '[' command ']' */
cmdPtr = infoPtr->next;
envPtr->pushSimpleWords = 1;
result = TclCompileString(interp, cmdPtr,
infoPtr->lastChar, (flags | TCL_BRACKET_TERM), envPtr);
if (result != TCL_OK) {
goto done;
}
termPtr = (cmdPtr + envPtr->termOffset);
if (*termPtr == ']') {
infoPtr->next = (termPtr + 1); /* advance over the ']'. */
} else if (termPtr == infoPtr->lastChar) {
/*
* Missing ] at end of nested command.
*/
Tcl_ResetResult(interp);
Tcl_AppendToObj(Tcl_GetObjResult(interp),
"missing close-bracket", -1);
result = TCL_ERROR;
goto done;
} else {
panic("CompilePrimaryExpr: unexpected termination char '%c' for nested command\n", *termPtr);
}
maxDepth = envPtr->maxStackDepth;
break;
case FUNC_NAME:
result = CompileMathFuncCall(interp, infoPtr, flags, envPtr);
if (result != TCL_OK) {
goto done;
}
maxDepth = envPtr->maxStackDepth;
break;
case OPEN_PAREN:
result = GetToken(interp, infoPtr, envPtr); /* skip over the '(' */
if (result != TCL_OK) {
goto done;
}
infoPtr->exprIsComparison = 0;
result = CompileCondExpr(interp, infoPtr, flags, envPtr);
if (result != TCL_OK) {
goto done;
}
maxDepth = envPtr->maxStackDepth;
if (infoPtr->token != CLOSE_PAREN) {
goto syntaxError;
}
break;
default:
goto syntaxError;
}
if (theToken != FUNC_NAME) {
/*
* Advance to the next token before returning.
*/
result = GetToken(interp, infoPtr, envPtr);
if (result != TCL_OK) {
goto done;
}
}
done:
envPtr->maxStackDepth = maxDepth;
return result;
syntaxError:
Tcl_AppendStringsToObj(Tcl_GetObjResult(interp),
"syntax error in expression \"", infoPtr->originalExpr,
"\"", (char *) NULL);
return TCL_ERROR;
}
/*
*----------------------------------------------------------------------
*
* CompileMathFuncCall --
*
* This procedure compiles a call on a math function in an expression:
* mathFuncCall ::= funcName '(' [condExpr {',' condExpr}] ')'
*
* Results:
* The return value is TCL_OK on a successful compilation and TCL_ERROR
* on failure. If TCL_ERROR is returned, then the interpreter's result
* contains an error message.
*
* envPtr->maxStackDepth is updated with the maximum number of stack
* elements needed to execute the function.
*
* Side effects:
* Adds instructions to envPtr to evaluate the math function at
* runtime.
*
*----------------------------------------------------------------------
*/
static int
CompileMathFuncCall(interp, infoPtr, flags, envPtr)
Tcl_Interp *interp; /* Used for error reporting. */
ExprInfo *infoPtr; /* Describes the compilation state for the
* expression being compiled. */
int flags; /* Flags to control compilation (same as
* passed to Tcl_Eval). */
CompileEnv *envPtr; /* Holds resulting instructions. */
{
Interp *iPtr = (Interp *) interp;
int maxDepth = 0; /* Maximum number of stack elements needed
* to execute the expression. */
MathFunc *mathFuncPtr; /* Info about math function. */
int objIndex; /* The object array index for an object
* holding the function name if it is not
* builtin. */
Tcl_HashEntry *hPtr;
char *p, *funcName;
char savedChar;
int result, i;
/*
* infoPtr->funcName points to the first character of the math
* function's name. Look for the end of its name and look up the
* MathFunc record for the function.
*/
funcName = p = infoPtr->funcName;
while (isalnum(UCHAR(*p)) || (*p == '_')) {
p++;
}
infoPtr->next = p;
result = GetToken(interp, infoPtr, envPtr); /* skip over func name */
if (result != TCL_OK) {
goto done;
}
if (infoPtr->token != OPEN_PAREN) {
goto syntaxError;
}
result = GetToken(interp, infoPtr, envPtr); /* skip over '(' */
if (result != TCL_OK) {
goto done;
}
savedChar = *p;
*p = 0;
hPtr = Tcl_FindHashEntry(&iPtr->mathFuncTable, funcName);
if (hPtr == NULL) {
Tcl_AppendStringsToObj(Tcl_GetObjResult(interp),
"unknown math function \"", funcName, "\"", (char *) NULL);
result = TCL_ERROR;
*p = savedChar;
goto done;
}
mathFuncPtr = (MathFunc *) Tcl_GetHashValue(hPtr);
/*
* If not a builtin function, push an object with the function's name.
*/
if (mathFuncPtr->builtinFuncIndex < 0) { /* not builtin */
objIndex = TclObjIndexForString(funcName, -1, /*allocStrRep*/ 1,
/*inHeap*/ 0, envPtr);
TclEmitPush(objIndex, envPtr);
maxDepth = 1;
}
/*
* Restore the saved character after the function name.
*/
*p = savedChar;
/*
* Compile the arguments for the function, if there are any.
*/
if (mathFuncPtr->numArgs > 0) {
for (i = 0; ; i++) {
infoPtr->exprIsComparison = 0;
result = CompileCondExpr(interp, infoPtr, flags, envPtr);
if (result != TCL_OK) {
goto done;
}
/*
* Check for a ',' between arguments or a ')' ending the
* argument list.
*/
if (i == (mathFuncPtr->numArgs-1)) {
if (infoPtr->token == CLOSE_PAREN) {
break; /* exit the argument parsing loop */
} else if (infoPtr->token == COMMA) {
Tcl_ResetResult(interp);
Tcl_AppendToObj(Tcl_GetObjResult(interp),
"too many arguments for math function", -1);
result = TCL_ERROR;
goto done;
} else {
goto syntaxError;
}
}
if (infoPtr->token != COMMA) {
if (infoPtr->token == CLOSE_PAREN) {
Tcl_ResetResult(interp);
Tcl_AppendToObj(Tcl_GetObjResult(interp),
"too few arguments for math function", -1);
result = TCL_ERROR;
goto done;
} else {
goto syntaxError;
}
}
result = GetToken(interp, infoPtr, envPtr); /* skip over , */
if (result != TCL_OK) {
goto done;
}
maxDepth++;
}
}
if (infoPtr->token != CLOSE_PAREN) {
goto syntaxError;
}
result = GetToken(interp, infoPtr, envPtr); /* skip over ')' */
if (result != TCL_OK) {
goto done;
}
/*
* Compile the call on the math function. Note that the "objc" argument
* count for non-builtin functions is incremented by 1 to include the
* the function name itself.
*/
if (mathFuncPtr->builtinFuncIndex >= 0) { /* a builtin function */
TclEmitInstUInt1(INST_CALL_BUILTIN_FUNC1,
mathFuncPtr->builtinFuncIndex, envPtr);
} else {
TclEmitInstUInt1(INST_CALL_FUNC1, (mathFuncPtr->numArgs+1), envPtr);
}
/*
* A comparison is not the top-level operator in this expression.
*/
done:
infoPtr->exprIsComparison = 0;
envPtr->maxStackDepth = maxDepth;
return result;
syntaxError:
Tcl_AppendStringsToObj(Tcl_GetObjResult(interp),
"syntax error in expression \"", infoPtr->originalExpr,
"\"", (char *) NULL);
return TCL_ERROR;
}
/*
*----------------------------------------------------------------------
*
* GetToken --
*
* Lexical scanner used to compile expressions: parses a single
* operator or other syntactic element from an expression string.
*
* Results:
* TCL_OK is returned unless an error occurred. In that case a standard
* Tcl error is returned, using the interpreter's result to hold an
* error message. TCL_ERROR is returned if an integer overflow, or a
* floating-point overflow or underflow occurred while reading in a
* number. If the lexical analysis is successful, infoPtr->token refers
* to the next symbol in the expression string, and infoPtr->next is
* advanced past the token. Also, if the token is a integer, double, or
* string literal, then infoPtr->objIndex the index of an object
* holding the value in the code's object table; otherwise is NULL.
*
* Side effects:
* Object are added to envPtr to hold the values of scanned literal
* integers, doubles, or strings.
*
*----------------------------------------------------------------------
*/
static int
GetToken(interp, infoPtr, envPtr)
Tcl_Interp *interp; /* Interpreter to use for error
* reporting. */
register ExprInfo *infoPtr; /* Describes the state of the
* compiling the expression,
* including the resulting token. */
CompileEnv *envPtr; /* Holds objects that store literal
* values that are scanned. */
{
register char *src; /* Points to current source char. */
register char c; /* The current char. */
register int type; /* Current char's CHAR_TYPE type. */
char *termPtr; /* Points to char terminating a literal. */
char savedChar; /* Holds the character termporarily replaced
* by a null character during processing of
* literal tokens. */
int objIndex; /* The object array index for an object
* holding a scanned literal. */
long longValue; /* Value of a scanned integer literal. */
double doubleValue; /* Value of a scanned double literal. */
Tcl_Obj *objPtr;
/*
* First initialize the scanner's "result" fields to default values.
*/
infoPtr->token = UNKNOWN;
infoPtr->objIndex = -1;
infoPtr->funcName = NULL;
/*
* Scan over leading white space at the start of a token. Note that a
* backslash-newline is treated as a space.
*/
src = infoPtr->next;
c = *src;
type = CHAR_TYPE(src, infoPtr->lastChar);
while ((type & (TCL_SPACE | TCL_BACKSLASH)) || (c == '\n')) {
if (type == TCL_BACKSLASH) {
if (src[1] == '\n') {
src += 2;
} else {
break; /* no longer white space */
}
} else {
src++;
}
c = *src;
type = CHAR_TYPE(src, infoPtr->lastChar);
}
if (src == infoPtr->lastChar) {
infoPtr->token = END;
infoPtr->next = src;
return TCL_OK;
}
/*
* Try to parse the token first as an integer or floating-point
* number. Don't check for a number if the first character is "+" or
* "-". If we did, we might treat a binary operator as unary by mistake,
* which would eventually cause a syntax error.
*/
if ((*src != '+') && (*src != '-')) {
int startsWithDigit = isdigit(UCHAR(*src));
if (startsWithDigit && TclLooksLikeInt(src)) {
errno = 0;
longValue = strtoul(src, &termPtr, 0);
if (errno == ERANGE) {
char *s = "integer value too large to represent";
Tcl_ResetResult(interp);
Tcl_AppendToObj(Tcl_GetObjResult(interp), s, -1);
Tcl_SetErrorCode(interp, "ARITH", "IOVERFLOW", s,
(char *) NULL);
return TCL_ERROR;
}
/*
* Find/create an object in envPtr's object array that contains
* the integer.
*/
savedChar = *termPtr;
*termPtr = '\0';
objIndex = TclObjIndexForString(src, termPtr - src,
/*allocStrRep*/ 0, /*inHeap*/ 0, envPtr);
*termPtr = savedChar; /* restore the saved char */
objPtr = envPtr->objArrayPtr[objIndex];
Tcl_InvalidateStringRep(objPtr);
objPtr->internalRep.longValue = longValue;
objPtr->typePtr = &tclIntType;
infoPtr->token = LITERAL;
infoPtr->objIndex = objIndex;
infoPtr->next = termPtr;
return TCL_OK;
} else if (startsWithDigit || (*src == '.')
|| (*src == 'n') || (*src == 'N')) {
errno = 0;
doubleValue = strtod(src, &termPtr);
if (termPtr != src) {
if (errno != 0) {
TclExprFloatError(interp, doubleValue);
return TCL_ERROR;
}
/*
* Find/create an object in the object array containing the
* double.
*/
savedChar = *termPtr;
*termPtr = '\0';
objIndex = TclObjIndexForString(src, termPtr - src,
/*allocStrRep*/ 1, /*inHeap*/ 0, envPtr);
*termPtr = savedChar; /* restore the saved char */
objPtr = envPtr->objArrayPtr[objIndex];
objPtr->internalRep.doubleValue = doubleValue;
objPtr->typePtr = &tclDoubleType;
infoPtr->token = LITERAL;
infoPtr->objIndex = objIndex;
infoPtr->next = termPtr;
return TCL_OK;
}
}
}
/*
* Not an integer or double literal. Check next for a string literal
* in braces.
*/
if (*src == '{') {
int level = 0; /* The {} nesting level. */
int hasBackslashNL = 0; /* Nonzero if '\newline' was found. */
char *string = src+1; /* Points just after the starting '{'. */
char *last; /* Points just before terminating '}'. */
int numChars; /* Number of chars in braced string. */
char savedChar; /* Holds the character from string
* termporarily replaced by a null char
* during braced string processing. */
int numRead;
/*
* Check first for any backslash-newlines, since we must treat
* backslash-newlines specially (they must be replaced by spaces).
*/
while (1) {
if (src == infoPtr->lastChar) {
Tcl_ResetResult(interp);
Tcl_AppendToObj(Tcl_GetObjResult(interp),
"missing close-brace", -1);
return TCL_ERROR;
} else if (CHAR_TYPE(src, infoPtr->lastChar) == TCL_NORMAL) {
src++;
continue;
}
c = *src++;
if (c == '{') {
level++;
} else if (c == '}') {
--level;
if (level == 0) {
last = (src - 2); /* i.e. just before terminating } */
break;
}
} else if (c == '\\') {
if (*src == '\n') {
hasBackslashNL = 1;
}
(void) Tcl_Backslash(src-1, &numRead);
src += numRead - 1;
}
}
/*
* Create a string object for the braced string. This starts at
* "string" and ends just after "last" (which points to the final
* character before the terminating '}'). If backslash-newlines were
* found, we copy characters one at a time into a heap-allocated
* buffer and do backslash-newline substitutions.
*/
numChars = (last - string + 1);
savedChar = string[numChars];
string[numChars] = '\0';
if (hasBackslashNL && (numChars > 0)) {
char *buffer = ckalloc((unsigned) numChars + 1);
register char *dst = buffer;
register char *p = string;
while (p <= last) {
c = *dst++ = *p++;
if (c == '\\') {
if (*p == '\n') {
dst[-1] = Tcl_Backslash(p-1, &numRead);
p += numRead - 1;
} else {
(void) Tcl_Backslash(p-1, &numRead);
while (numRead > 1) {
*dst++ = *p++;
numRead--;
}
}
}
}
*dst = '\0';
objIndex = TclObjIndexForString(buffer, dst - buffer,
/*allocStrRep*/ 1, /*inHeap*/ 1, envPtr);
} else {
objIndex = TclObjIndexForString(string, numChars,
/*allocStrRep*/ 1, /*inHeap*/ 0, envPtr);
}
string[numChars] = savedChar; /* restore the saved char */
infoPtr->token = LITERAL;
infoPtr->objIndex = objIndex;
infoPtr->next = src;
return TCL_OK;
}
/*
* Not an literal value.
*/
infoPtr->next = src+1; /* assume a 1 char token and advance over it */
switch (*src) {
case '[':
infoPtr->token = OPEN_BRACKET;
return TCL_OK;
case ']':
infoPtr->token = CLOSE_BRACKET;
return TCL_OK;
case '(':
infoPtr->token = OPEN_PAREN;
return TCL_OK;
case ')':
infoPtr->token = CLOSE_PAREN;
return TCL_OK;
case '$':
infoPtr->token = DOLLAR;
return TCL_OK;
case '"':
infoPtr->token = QUOTE;
return TCL_OK;
case ',':
infoPtr->token = COMMA;
return TCL_OK;
case '*':
infoPtr->token = MULT;
return TCL_OK;
case '/':
infoPtr->token = DIVIDE;
return TCL_OK;
case '%':
infoPtr->token = MOD;
return TCL_OK;
case '+':
infoPtr->token = PLUS;
return TCL_OK;
case '-':
infoPtr->token = MINUS;
return TCL_OK;
case '?':
infoPtr->token = QUESTY;
return TCL_OK;
case ':':
infoPtr->token = COLON;
return TCL_OK;
case '<':
switch (src[1]) {
case '<':
infoPtr->next = src+2;
infoPtr->token = LEFT_SHIFT;
break;
case '=':
infoPtr->next = src+2;
infoPtr->token = LEQ;
break;
default:
infoPtr->token = LESS;
break;
}
return TCL_OK;
case '>':
switch (src[1]) {
case '>':
infoPtr->next = src+2;
infoPtr->token = RIGHT_SHIFT;
break;
case '=':
infoPtr->next = src+2;
infoPtr->token = GEQ;
break;
default:
infoPtr->token = GREATER;
break;
}
return TCL_OK;
case '=':
if (src[1] == '=') {
infoPtr->next = src+2;
infoPtr->token = EQUAL;
} else {
infoPtr->token = UNKNOWN;
}
return TCL_OK;
case '!':
if (src[1] == '=') {
infoPtr->next = src+2;
infoPtr->token = NEQ;
} else {
infoPtr->token = NOT;
}
return TCL_OK;
case '&':
if (src[1] == '&') {
infoPtr->next = src+2;
infoPtr->token = AND;
} else {
infoPtr->token = BIT_AND;
}
return TCL_OK;
case '^':
infoPtr->token = BIT_XOR;
return TCL_OK;
case '|':
if (src[1] == '|') {
infoPtr->next = src+2;
infoPtr->token = OR;
} else {
infoPtr->token = BIT_OR;
}
return TCL_OK;
case '~':
infoPtr->token = BIT_NOT;
return TCL_OK;
default:
if (isalpha(UCHAR(*src))) {
infoPtr->token = FUNC_NAME;
infoPtr->funcName = src;
while (isalnum(UCHAR(*src)) || (*src == '_')) {
src++;
}
infoPtr->next = src;
return TCL_OK;
}
infoPtr->next = src+1;
infoPtr->token = UNKNOWN;
return TCL_OK;
}
}
/*
*----------------------------------------------------------------------
*
* Tcl_CreateMathFunc --
*
* Creates a new math function for expressions in a given
* interpreter.
*
* Results:
* None.
*
* Side effects:
* The function defined by "name" is created or redefined. If the
* function already exists then its definition is replaced; this
* includes the builtin functions. Redefining a builtin function forces
* all existing code to be invalidated since that code may be compiled
* using an instruction specific to the replaced function. In addition,
* redefioning a non-builtin function will force existing code to be
* invalidated if the number of arguments has changed.
*
*----------------------------------------------------------------------
*/
void
Tcl_CreateMathFunc(interp, name, numArgs, argTypes, proc, clientData)
Tcl_Interp *interp; /* Interpreter in which function is
* to be available. */
char *name; /* Name of function (e.g. "sin"). */
int numArgs; /* Nnumber of arguments required by
* function. */
Tcl_ValueType *argTypes; /* Array of types acceptable for
* each argument. */
Tcl_MathProc *proc; /* Procedure that implements the
* math function. */
ClientData clientData; /* Additional value to pass to the
* function. */
{
Interp *iPtr = (Interp *) interp;
Tcl_HashEntry *hPtr;
MathFunc *mathFuncPtr;
int new, i;
hPtr = Tcl_CreateHashEntry(&iPtr->mathFuncTable, name, &new);
if (new) {
Tcl_SetHashValue(hPtr, ckalloc(sizeof(MathFunc)));
}
mathFuncPtr = (MathFunc *) Tcl_GetHashValue(hPtr);
if (!new) {
if (mathFuncPtr->builtinFuncIndex >= 0) {
/*
* We are redefining a builtin math function. Invalidate the
* interpreter's existing code by incrementing its
* compileEpoch member. This field is checked in Tcl_EvalObj
* and ObjInterpProc, and code whose compilation epoch doesn't
* match is recompiled. Newly compiled code will no longer
* treat the function as builtin.
*/
iPtr->compileEpoch++;
} else {
/*
* A non-builtin function is being redefined. We must invalidate
* existing code if the number of arguments has changed. This
* is because existing code was compiled assuming that number.
*/
if (numArgs != mathFuncPtr->numArgs) {
iPtr->compileEpoch++;
}
}
}
mathFuncPtr->builtinFuncIndex = -1; /* can't be a builtin function */
if (numArgs > MAX_MATH_ARGS) {
numArgs = MAX_MATH_ARGS;
}
mathFuncPtr->numArgs = numArgs;
for (i = 0; i < numArgs; i++) {
mathFuncPtr->argTypes[i] = argTypes[i];
}
mathFuncPtr->proc = proc;
mathFuncPtr->clientData = clientData;
}
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