Split tclCompCmds.c into two pieces to improve developer sanity.

1 files changed, 3499 insertions, 0 deletions

diff --git a/generic/tclCompCmdsSZ.c b/generic/tclCompCmdsSZ.c
new file mode 100644
index 0000000..88954ed
--- /dev/null
+++ b/generic/tclCompCmdsSZ.c
@@ -0,0 +1,3499 @@
+/*
+ * tclCompCmdsSZ.c --
+ *
+ *	This file contains compilation procedures that compile various Tcl
+ *	commands (beginning with the letters 's' through 'z', except for
+ *	[upvar] and [variable]) into a sequence of instructions ("bytecodes").
+ *	Also includes the operator command compilers.
+ *
+ * Copyright (c) 1997-1998 Sun Microsystems, Inc.
+ * Copyright (c) 2001 by Kevin B. Kenny.  All rights reserved.
+ * Copyright (c) 2002 ActiveState Corporation.
+ * Copyright (c) 2004-2010 by Donal K. Fellows.
+ *
+ * See the file "license.terms" for information on usage and redistribution of
+ * this file, and for a DISCLAIMER OF ALL WARRANTIES.
+ *
+ * RCS: @(#) $Id: tclCompCmdsSZ.c,v 1.1 2010/02/26 14:38:36 dkf Exp $
+ */
+
+#include "tclInt.h"
+#include "tclCompile.h"
+
+/*
+ * Prototypes for procedures defined later in this file:
+ */
+
+static ClientData	DupJumptableInfo(ClientData clientData);
+static void		FreeJumptableInfo(ClientData clientData);
+static void		PrintJumptableInfo(ClientData clientData,
+			    Tcl_Obj *appendObj, ByteCode *codePtr,
+			    unsigned int pcOffset);
+static int		PushVarName(Tcl_Interp *interp,
+			    Tcl_Token *varTokenPtr, CompileEnv *envPtr,
+			    int flags, int *localIndexPtr,
+			    int *simpleVarNamePtr, int *isScalarPtr,
+			    int line, int *clNext);
+static int		CompileAssociativeBinaryOpCmd(Tcl_Interp *interp,
+			    Tcl_Parse *parsePtr, const char *identity,
+			    int instruction, CompileEnv *envPtr);
+static int		CompileComparisonOpCmd(Tcl_Interp *interp,
+			    Tcl_Parse *parsePtr, int instruction,
+			    CompileEnv *envPtr);
+static int		CompileStrictlyBinaryOpCmd(Tcl_Interp *interp,
+			    Tcl_Parse *parsePtr, int instruction,
+			    CompileEnv *envPtr);
+static int		CompileUnaryOpCmd(Tcl_Interp *interp,
+			    Tcl_Parse *parsePtr, int instruction,
+			    CompileEnv *envPtr);
+static void		IssueSwitchChainedTests(Tcl_Interp *interp,
+			    CompileEnv *envPtr, ExtCmdLoc *mapPtr,
+			    int eclIndex, int mode, int noCase,
+			    int valueIndex, Tcl_Token *valueTokenPtr,
+			    int numWords, Tcl_Token **bodyToken,
+			    int *bodyLines, int **bodyNext);
+static void		IssueSwitchJumpTable(Tcl_Interp *interp,
+			    CompileEnv *envPtr, ExtCmdLoc *mapPtr,
+			    int eclIndex, int valueIndex,
+			    Tcl_Token *valueTokenPtr, int numWords,
+			    Tcl_Token **bodyToken, int *bodyLines,
+			    int **bodyContLines);
+static int		IssueTryFinallyInstructions(Tcl_Interp *interp,
+			    CompileEnv *envPtr, Tcl_Token *bodyToken,
+			    int numHandlers, int *matchCodes,
+			    Tcl_Obj **matchClauses, int *resultVarIndices,
+			    int *optionVarIndices, Tcl_Token **handlerTokens,
+			    Tcl_Token *finallyToken);
+static int		IssueTryInstructions(Tcl_Interp *interp,
+			    CompileEnv *envPtr, Tcl_Token *bodyToken,
+			    int numHandlers, int *matchCodes,
+			    Tcl_Obj **matchClauses, int *resultVarIndices,
+			    int *optionVarIndices, Tcl_Token **handlerTokens);
+
+/*
+ * Macro that encapsulates an efficiency trick that avoids a function call for
+ * the simplest of compiles. The ANSI C "prototype" for this macro is:
+ *
+ * static void		CompileWord(CompileEnv *envPtr, Tcl_Token *tokenPtr,
+ *			    Tcl_Interp *interp, int word);
+ */
+
+#define CompileWord(envPtr, tokenPtr, interp, word) \
+    if ((tokenPtr)->type == TCL_TOKEN_SIMPLE_WORD) {			\
+	TclEmitPush(TclRegisterNewLiteral((envPtr), (tokenPtr)[1].start, \
+		(tokenPtr)[1].size), (envPtr));				\
+    } else {								\
+	envPtr->line = mapPtr->loc[eclIndex].line[word];		\
+	envPtr->clNext = mapPtr->loc[eclIndex].next[word];		\
+	TclCompileTokens((interp), (tokenPtr)+1, (tokenPtr)->numComponents, \
+		(envPtr));						\
+    }
+
+/*
+ * TIP #280: Remember the per-word line information of the current command. An
+ * index is used instead of a pointer as recursive compilation may reallocate,
+ * i.e. move, the array. This is also the reason to save the nuloc now, it may
+ * change during the course of the function.
+ *
+ * Macro to encapsulate the variable definition and setup.
+ */
+
+#define DefineLineInformation \
+    ExtCmdLoc *mapPtr = envPtr->extCmdMapPtr;				\
+    int eclIndex = mapPtr->nuloc - 1
+
+#define SetLineInformation(word) \
+    envPtr->line = mapPtr->loc[eclIndex].line[(word)];			\
+    envPtr->clNext = mapPtr->loc[eclIndex].next[(word)]
+
+#define PushVarNameWord(i,v,e,f,l,s,sc,word) \
+    PushVarName(i,v,e,f,l,s,sc,						\
+	    mapPtr->loc[eclIndex].line[(word)],				\
+	    mapPtr->loc[eclIndex].next[(word)])
+
+/*
+ * Flags bits used by PushVarName.
+ */
+
+#define TCL_NO_LARGE_INDEX 1	/* Do not return localIndex value > 255 */
+
+/*
+ * The structures below define the AuxData types defined in this file.
+ */
+
+const AuxDataType tclJumptableInfoType = {
+    "JumptableInfo",		/* name */
+    DupJumptableInfo,		/* dupProc */
+    FreeJumptableInfo,		/* freeProc */
+    PrintJumptableInfo		/* printProc */
+};
+
+/*
+ * Shorthand macros for instruction issuing.
+ */
+
+#define OP(name)	TclEmitOpcode(INST_##name, envPtr)
+#define OP1(name,val)	TclEmitInstInt1(INST_##name,(val),envPtr)
+#define OP4(name,val)	TclEmitInstInt4(INST_##name,(val),envPtr)
+#define OP44(name,val1,val2) \
+    TclEmitInstInt4(INST_##name,(val1),envPtr);TclEmitInt4((val2),envPtr)
+#define BODY(token,index) \
+    SetLineInformation((index));CompileBody(envPtr,(token),interp)
+#define PUSH(str) \
+    PushLiteral(envPtr,(str),strlen(str))
+#define JUMP(var,name) \
+    (var) = CurrentOffset(envPtr);TclEmitInstInt4(INST_##name,0,envPtr)
+#define FIXJUMP(var) \
+    TclStoreInt4AtPtr(CurrentOffset(envPtr)-(var),envPtr->codeStart+(var)+1)
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclCompileSetCmd --
+ *
+ *	Procedure called to compile the "set" command.
+ *
+ * Results:
+ *	Returns TCL_OK for a successful compile. Returns TCL_ERROR to defer
+ *	evaluation to runtime.
+ *
+ * Side effects:
+ *	Instructions are added to envPtr to execute the "set" command at
+ *	runtime.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+TclCompileSetCmd(
+    Tcl_Interp *interp,		/* Used for error reporting. */
+    Tcl_Parse *parsePtr,	/* Points to a parse structure for the command
+				 * created by Tcl_ParseCommand. */
+    Command *cmdPtr,		/* Points to defintion of command being
+				 * compiled. */
+    CompileEnv *envPtr)		/* Holds resulting instructions. */
+{
+    Tcl_Token *varTokenPtr, *valueTokenPtr;
+    int isAssignment, isScalar, simpleVarName, localIndex, numWords;
+    DefineLineInformation;	/* TIP #280 */
+
+    numWords = parsePtr->numWords;
+    if ((numWords != 2) && (numWords != 3)) {
+	return TCL_ERROR;
+    }
+    isAssignment = (numWords == 3);
+
+    /*
+     * Decide if we can use a frame slot for the var/array name or if we need
+     * to emit code to compute and push the name at runtime. We use a frame
+     * slot (entry in the array of local vars) if we are compiling a procedure
+     * body and if the name is simple text that does not include namespace
+     * qualifiers.
+     */
+
+    varTokenPtr = TokenAfter(parsePtr->tokenPtr);
+    PushVarNameWord(interp, varTokenPtr, envPtr, 0,
+	    &localIndex, &simpleVarName, &isScalar, 1);
+
+    /*
+     * If we are doing an assignment, push the new value.
+     */
+
+    if (isAssignment) {
+	valueTokenPtr = TokenAfter(varTokenPtr);
+	CompileWord(envPtr, valueTokenPtr, interp, 2);
+    }
+
+    /*
+     * Emit instructions to set/get the variable.
+     */
+
+    if (simpleVarName) {
+	if (isScalar) {
+	    if (localIndex < 0) {
+		TclEmitOpcode((isAssignment?
+			INST_STORE_SCALAR_STK : INST_LOAD_SCALAR_STK),
+			envPtr);
+	    } else if (localIndex <= 255) {
+		TclEmitInstInt1((isAssignment?
+			INST_STORE_SCALAR1 : INST_LOAD_SCALAR1),
+			localIndex, envPtr);
+	    } else {
+		TclEmitInstInt4((isAssignment?
+			INST_STORE_SCALAR4 : INST_LOAD_SCALAR4),
+			localIndex, envPtr);
+	    }
+	} else {
+	    if (localIndex < 0) {
+		TclEmitOpcode((isAssignment?
+			INST_STORE_ARRAY_STK : INST_LOAD_ARRAY_STK), envPtr);
+	    } else if (localIndex <= 255) {
+		TclEmitInstInt1((isAssignment?
+			INST_STORE_ARRAY1 : INST_LOAD_ARRAY1),
+			localIndex, envPtr);
+	    } else {
+		TclEmitInstInt4((isAssignment?
+			INST_STORE_ARRAY4 : INST_LOAD_ARRAY4),
+			localIndex, envPtr);
+	    }
+	}
+    } else {
+	TclEmitOpcode((isAssignment? INST_STORE_STK : INST_LOAD_STK), envPtr);
+    }
+
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclCompileStringCmpCmd --
+ *
+ *	Procedure called to compile the simplest and most common form of the
+ *	"string compare" command.
+ *
+ * Results:
+ *	Returns TCL_OK for a successful compile. Returns TCL_ERROR to defer
+ *	evaluation to runtime.
+ *
+ * Side effects:
+ *	Instructions are added to envPtr to execute the "string compare"
+ *	command at runtime.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+TclCompileStringCmpCmd(
+    Tcl_Interp *interp,		/* Used for error reporting. */
+    Tcl_Parse *parsePtr,	/* Points to a parse structure for the command
+				 * created by Tcl_ParseCommand. */
+    Command *cmdPtr,		/* Points to defintion of command being
+				 * compiled. */
+    CompileEnv *envPtr)		/* Holds resulting instructions. */
+{
+    DefineLineInformation;	/* TIP #280 */
+    Tcl_Token *tokenPtr;
+
+    /*
+     * We don't support any flags; the bytecode isn't that sophisticated.
+     */
+
+    if (parsePtr->numWords != 3) {
+	return TCL_ERROR;
+    }
+
+    /*
+     * Push the two operands onto the stack and then the test.
+     */
+
+    tokenPtr = TokenAfter(parsePtr->tokenPtr);
+    CompileWord(envPtr, tokenPtr, interp, 1);
+    tokenPtr = TokenAfter(tokenPtr);
+    CompileWord(envPtr, tokenPtr, interp, 2);
+    TclEmitOpcode(INST_STR_CMP, envPtr);
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclCompileStringEqualCmd --
+ *
+ *	Procedure called to compile the simplest and most common form of the
+ *	"string equal" command.
+ *
+ * Results:
+ *	Returns TCL_OK for a successful compile. Returns TCL_ERROR to defer
+ *	evaluation to runtime.
+ *
+ * Side effects:
+ *	Instructions are added to envPtr to execute the "string equal" command
+ *	at runtime.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+TclCompileStringEqualCmd(
+    Tcl_Interp *interp,		/* Used for error reporting. */
+    Tcl_Parse *parsePtr,	/* Points to a parse structure for the command
+				 * created by Tcl_ParseCommand. */
+    Command *cmdPtr,		/* Points to defintion of command being
+				 * compiled. */
+    CompileEnv *envPtr)		/* Holds resulting instructions. */
+{
+    DefineLineInformation;	/* TIP #280 */
+    Tcl_Token *tokenPtr;
+
+    /*
+     * We don't support any flags; the bytecode isn't that sophisticated.
+     */
+
+    if (parsePtr->numWords != 3) {
+	return TCL_ERROR;
+    }
+
+    /*
+     * Push the two operands onto the stack and then the test.
+     */
+
+    tokenPtr = TokenAfter(parsePtr->tokenPtr);
+    CompileWord(envPtr, tokenPtr, interp, 1);
+    tokenPtr = TokenAfter(tokenPtr);
+    CompileWord(envPtr, tokenPtr, interp, 2);
+    TclEmitOpcode(INST_STR_EQ, envPtr);
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclCompileStringIndexCmd --
+ *
+ *	Procedure called to compile the simplest and most common form of the
+ *	"string index" command.
+ *
+ * Results:
+ *	Returns TCL_OK for a successful compile. Returns TCL_ERROR to defer
+ *	evaluation to runtime.
+ *
+ * Side effects:
+ *	Instructions are added to envPtr to execute the "string index" command
+ *	at runtime.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+TclCompileStringIndexCmd(
+    Tcl_Interp *interp,		/* Used for error reporting. */
+    Tcl_Parse *parsePtr,	/* Points to a parse structure for the command
+				 * created by Tcl_ParseCommand. */
+    Command *cmdPtr,		/* Points to defintion of command being
+				 * compiled. */
+    CompileEnv *envPtr)		/* Holds resulting instructions. */
+{
+    DefineLineInformation;	/* TIP #280 */
+    Tcl_Token *tokenPtr;
+
+    if (parsePtr->numWords != 3) {
+	return TCL_ERROR;
+    }
+
+    /*
+     * Push the two operands onto the stack and then the index operation.
+     */
+
+    tokenPtr = TokenAfter(parsePtr->tokenPtr);
+    CompileWord(envPtr, tokenPtr, interp, 1);
+    tokenPtr = TokenAfter(tokenPtr);
+    CompileWord(envPtr, tokenPtr, interp, 2);
+    TclEmitOpcode(INST_STR_INDEX, envPtr);
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclCompileStringMatchCmd --
+ *
+ *	Procedure called to compile the simplest and most common form of the
+ *	"string match" command.
+ *
+ * Results:
+ *	Returns TCL_OK for a successful compile. Returns TCL_ERROR to defer
+ *	evaluation to runtime.
+ *
+ * Side effects:
+ *	Instructions are added to envPtr to execute the "string match" command
+ *	at runtime.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+TclCompileStringMatchCmd(
+    Tcl_Interp *interp,		/* Used for error reporting. */
+    Tcl_Parse *parsePtr,	/* Points to a parse structure for the command
+				 * created by Tcl_ParseCommand. */
+    Command *cmdPtr,		/* Points to defintion of command being
+				 * compiled. */
+    CompileEnv *envPtr)		/* Holds resulting instructions. */
+{
+    DefineLineInformation;	/* TIP #280 */
+    Tcl_Token *tokenPtr;
+    int i, length, exactMatch = 0, nocase = 0;
+    const char *str;
+
+    if (parsePtr->numWords < 3 || parsePtr->numWords > 4) {
+	return TCL_ERROR;
+    }
+    tokenPtr = TokenAfter(parsePtr->tokenPtr);
+
+    /*
+     * Check if we have a -nocase flag.
+     */
+
+    if (parsePtr->numWords == 4) {
+	if (tokenPtr->type != TCL_TOKEN_SIMPLE_WORD) {
+	    return TCL_ERROR;
+	}
+	str = tokenPtr[1].start;
+	length = tokenPtr[1].size;
+	if ((length <= 1) || strncmp(str, "-nocase", (size_t) length)) {
+	    /*
+	     * Fail at run time, not in compilation.
+	     */
+
+	    return TCL_ERROR;
+	}
+	nocase = 1;
+	tokenPtr = TokenAfter(tokenPtr);
+    }
+
+    /*
+     * Push the strings to match against each other.
+     */
+
+    for (i = 0; i < 2; i++) {
+	if (tokenPtr->type == TCL_TOKEN_SIMPLE_WORD) {
+	    str = tokenPtr[1].start;
+	    length = tokenPtr[1].size;
+	    if (!nocase && (i == 0)) {
+		/*
+		 * Trivial matches can be done by 'string equal'. If -nocase
+		 * was specified, we can't do this because INST_STR_EQ has no
+		 * support for nocase.
+		 */
+
+		Tcl_Obj *copy = Tcl_NewStringObj(str, length);
+
+		Tcl_IncrRefCount(copy);
+		exactMatch = TclMatchIsTrivial(TclGetString(copy));
+		TclDecrRefCount(copy);
+	    }
+	    PushLiteral(envPtr, str, length);
+	} else {
+	    SetLineInformation(i+1+nocase);
+	    CompileTokens(envPtr, tokenPtr, interp);
+	}
+	tokenPtr = TokenAfter(tokenPtr);
+    }
+
+    /*
+     * Push the matcher.
+     */
+
+    if (exactMatch) {
+	TclEmitOpcode(INST_STR_EQ, envPtr);
+    } else {
+	TclEmitInstInt1(INST_STR_MATCH, nocase, envPtr);
+    }
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclCompileStringLenCmd --
+ *
+ *	Procedure called to compile the simplest and most common form of the
+ *	"string length" command.
+ *
+ * Results:
+ *	Returns TCL_OK for a successful compile. Returns TCL_ERROR to defer
+ *	evaluation to runtime.
+ *
+ * Side effects:
+ *	Instructions are added to envPtr to execute the "string length"
+ *	command at runtime.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+TclCompileStringLenCmd(
+    Tcl_Interp *interp,		/* Used for error reporting. */
+    Tcl_Parse *parsePtr,	/* Points to a parse structure for the command
+				 * created by Tcl_ParseCommand. */
+    Command *cmdPtr,		/* Points to defintion of command being
+				 * compiled. */
+    CompileEnv *envPtr)		/* Holds resulting instructions. */
+{
+    DefineLineInformation;	/* TIP #280 */
+    Tcl_Token *tokenPtr;
+    Tcl_Obj *objPtr;
+
+    if (parsePtr->numWords != 2) {
+	return TCL_ERROR;
+    }
+
+    tokenPtr = TokenAfter(parsePtr->tokenPtr);
+    TclNewObj(objPtr);
+    if (TclWordKnownAtCompileTime(tokenPtr, objPtr)) {
+	/*
+	 * Here someone is asking for the length of a static string (or
+	 * something with backslashes). Just push the actual character (not
+	 * byte) length.
+	 */
+
+	char buf[TCL_INTEGER_SPACE];
+	int len = Tcl_GetCharLength(objPtr);
+
+	len = sprintf(buf, "%d", len);
+	PushLiteral(envPtr, buf, len);
+    } else {
+	SetLineInformation(1);
+	CompileTokens(envPtr, tokenPtr, interp);
+	TclEmitOpcode(INST_STR_LEN, envPtr);
+    }
+    TclDecrRefCount(objPtr);
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclCompileSubstCmd --
+ *
+ *	Procedure called to compile the "subst" command.
+ *
+ * Results:
+ *	Returns TCL_OK for successful compile, or TCL_ERROR to defer
+ *	evaluation to runtime (either when it is too complex to get the
+ *	semantics right, or when we know for sure that it is an error but need
+ *	the error to happen at the right time).
+ *
+ * Side effects:
+ *	Instructions are added to envPtr to execute the "subst" command at
+ *	runtime.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+TclCompileSubstCmd(
+    Tcl_Interp *interp,		/* Used for error reporting. */
+    Tcl_Parse *parsePtr,	/* Points to a parse structure for the command
+				 * created by Tcl_ParseCommand. */
+    Command *cmdPtr,		/* Points to defintion of command being
+				 * compiled. */
+    CompileEnv *envPtr)		/* Holds resulting instructions. */
+{
+    int numArgs = parsePtr->numWords - 1;
+    int numOpts = numArgs - 1;
+    int objc, flags = TCL_SUBST_ALL;
+    Tcl_Obj **objv/*, *toSubst = NULL*/;
+    Tcl_Token *wordTokenPtr = TokenAfter(parsePtr->tokenPtr);
+    int code = TCL_ERROR;
+    DefineLineInformation;	/* TIP #280 */
+
+    if (numArgs == 0) {
+	return TCL_ERROR;
+    }
+
+    objv = TclStackAlloc(interp, /*numArgs*/ numOpts * sizeof(Tcl_Obj *));
+
+    for (objc = 0; objc < /*numArgs*/ numOpts; objc++) {
+	objv[objc] = Tcl_NewObj();
+	Tcl_IncrRefCount(objv[objc]);
+	if (!TclWordKnownAtCompileTime(wordTokenPtr, objv[objc])) {
+	    objc++;
+	    goto cleanup;
+	}
+	wordTokenPtr = TokenAfter(wordTokenPtr);
+    }
+
+/*
+    if (TclSubstOptions(NULL, numOpts, objv, &flags) == TCL_OK) {
+	toSubst = objv[numOpts];
+	Tcl_IncrRefCount(toSubst);
+    }
+*/
+
+    /* TODO: Figure out expansion to cover WordKnownAtCompileTime
+     *	The difficulty is that WKACT makes a copy, and if TclSubstParse
+     *	below parses the copy of the original source string, some deep
+     *	parts of the compile machinery get upset.  They want all pointers
+     *	stored in Tcl_Tokens to point back to the same original string.
+     */
+    if (wordTokenPtr->type == TCL_TOKEN_SIMPLE_WORD) {
+	code = TclSubstOptions(NULL, numOpts, objv, &flags);
+    }
+
+  cleanup:
+    while (--objc >= 0) {
+	TclDecrRefCount(objv[objc]);
+    }
+    TclStackFree(interp, objv);
+    if (/*toSubst == NULL*/ code != TCL_OK) {
+	return TCL_ERROR;
+    }
+
+    SetLineInformation(numArgs);
+    TclSubstCompile(interp, wordTokenPtr[1].start, wordTokenPtr[1].size,
+	    flags, mapPtr->loc[eclIndex].line[numArgs], envPtr);
+
+/*    TclDecrRefCount(toSubst);*/
+    return TCL_OK;
+}
+
+void
+TclSubstCompile(
+    Tcl_Interp *interp,
+    const char *bytes,
+    int numBytes,
+    int flags,
+    int line,
+    CompileEnv *envPtr)
+{
+    Tcl_Token *endTokenPtr, *tokenPtr;
+    int breakOffset = 0, count = 0, bline = line;
+    Tcl_Parse parse;
+    Tcl_InterpState state = NULL;
+
+    TclSubstParse(interp, bytes, numBytes, flags, &parse, &state);
+
+    for (tokenPtr = parse.tokenPtr, endTokenPtr = tokenPtr + parse.numTokens;
+	    tokenPtr < endTokenPtr; tokenPtr = TokenAfter(tokenPtr)) {
+	int length, literal, catchRange, breakJump;
+	char buf[TCL_UTF_MAX];
+	JumpFixup startFixup, okFixup, returnFixup, breakFixup;
+	JumpFixup continueFixup, otherFixup, endFixup;
+
+	switch (tokenPtr->type) {
+	case TCL_TOKEN_TEXT:
+	    literal = TclRegisterNewLiteral(envPtr,
+		    tokenPtr->start, tokenPtr->size);
+	    TclEmitPush(literal, envPtr);
+	    TclAdvanceLines(&bline, tokenPtr->start,
+		    tokenPtr->start + tokenPtr->size);
+	    count++;
+	    continue;
+	case TCL_TOKEN_BS:
+	    length = Tcl_UtfBackslash(tokenPtr->start, NULL, buf);
+	    literal = TclRegisterNewLiteral(envPtr, buf, length);
+	    TclEmitPush(literal, envPtr);
+	    count++;
+	    continue;
+	}
+
+	while (count > 255) {
+	    TclEmitInstInt1(INST_CONCAT1, 255, envPtr);
+	    count -= 254;
+	}
+	if (count > 1) {
+	    TclEmitInstInt1(INST_CONCAT1, count, envPtr);
+	    count = 1;
+	}
+
+	if (breakOffset == 0) {
+	    /* Jump to the start (jump over the jump to end) */
+	    TclEmitForwardJump(envPtr, TCL_UNCONDITIONAL_JUMP, &startFixup);
+
+	    /* Jump to the end (all BREAKs land here) */
+	    breakOffset = CurrentOffset(envPtr);
+	    TclEmitInstInt4(INST_JUMP4, 0, envPtr);
+
+	    /* Start */
+	    if (TclFixupForwardJumpToHere(envPtr, &startFixup, 127)) {
+		Tcl_Panic("TclCompileSubstCmd: bad start jump distance %d",
+			CurrentOffset(envPtr) - startFixup.codeOffset);
+	    }
+	}
+
+	envPtr->line = bline;
+	catchRange = DeclareExceptionRange(envPtr, CATCH_EXCEPTION_RANGE);
+	TclEmitInstInt4(INST_BEGIN_CATCH4, catchRange, envPtr);
+	ExceptionRangeStarts(envPtr, catchRange);
+
+	switch (tokenPtr->type) {
+	case TCL_TOKEN_COMMAND:
+	    TclCompileScript(interp, tokenPtr->start+1, tokenPtr->size-2,
+		    envPtr);
+	    count++;
+	    break;
+	case TCL_TOKEN_VARIABLE:
+	    TclCompileVarSubst(interp, tokenPtr, envPtr);
+	    count++;
+	    break;
+	default:
+	    Tcl_Panic("unexpected token type in TclCompileSubstCmd: %d",
+		    tokenPtr->type);
+	}
+
+	ExceptionRangeEnds(envPtr, catchRange);
+
+	/* Substitution produced TCL_OK */
+	TclEmitOpcode(INST_END_CATCH, envPtr);
+	TclEmitForwardJump(envPtr, TCL_UNCONDITIONAL_JUMP, &okFixup);
+
+	/* Exceptional return codes processed here */
+	ExceptionRangeTarget(envPtr, catchRange, catchOffset);
+	TclEmitOpcode(INST_PUSH_RETURN_OPTIONS, envPtr);
+	TclEmitOpcode(INST_PUSH_RESULT, envPtr);
+	TclEmitOpcode(INST_PUSH_RETURN_CODE, envPtr);
+	TclEmitOpcode(INST_END_CATCH, envPtr);
+	TclEmitOpcode(INST_RETURN_CODE_BRANCH, envPtr);
+
+	/* ERROR -> reraise it */
+	TclEmitOpcode(INST_RETURN_STK, envPtr);
+	TclEmitOpcode(INST_NOP, envPtr);
+
+	/* RETURN */
+	TclEmitForwardJump(envPtr, TCL_UNCONDITIONAL_JUMP, &returnFixup);
+
+	/* BREAK */
+	TclEmitForwardJump(envPtr, TCL_UNCONDITIONAL_JUMP, &breakFixup);
+
+	/* CONTINUE */
+	TclEmitForwardJump(envPtr, TCL_UNCONDITIONAL_JUMP, &continueFixup);
+
+	/* OTHER */
+	TclEmitForwardJump(envPtr, TCL_UNCONDITIONAL_JUMP, &otherFixup);
+
+	/* BREAK destination */
+	if (TclFixupForwardJumpToHere(envPtr, &breakFixup, 127)) {
+	    Tcl_Panic("TclCompileSubstCmd: bad break jump distance %d",
+		    CurrentOffset(envPtr) - breakFixup.codeOffset);
+	}
+	TclEmitOpcode(INST_POP, envPtr);
+	TclEmitOpcode(INST_POP, envPtr);
+
+	breakJump = CurrentOffset(envPtr) - breakOffset;
+	if (breakJump > 127) {
+	    TclEmitInstInt4(INST_JUMP4, -breakJump, envPtr);
+	} else {
+	    TclEmitInstInt1(INST_JUMP1, -breakJump, envPtr);
+	}
+
+	/* CONTINUE destination */
+	if (TclFixupForwardJumpToHere(envPtr, &continueFixup, 127)) {
+	    Tcl_Panic("TclCompileSubstCmd: bad continue jump distance %d",
+		    CurrentOffset(envPtr) - continueFixup.codeOffset);
+	}
+	TclEmitOpcode(INST_POP, envPtr);
+	TclEmitOpcode(INST_POP, envPtr);
+	TclEmitForwardJump(envPtr, TCL_UNCONDITIONAL_JUMP, &endFixup);
+
+	/* RETURN + other destination */
+	if (TclFixupForwardJumpToHere(envPtr, &returnFixup, 127)) {
+	    Tcl_Panic("TclCompileSubstCmd: bad return jump distance %d",
+		    CurrentOffset(envPtr) - returnFixup.codeOffset);
+	}
+	if (TclFixupForwardJumpToHere(envPtr, &otherFixup, 127)) {
+	    Tcl_Panic("TclCompileSubstCmd: bad other jump distance %d",
+		    CurrentOffset(envPtr) - otherFixup.codeOffset);
+	}
+	/* Pull the result to top of stack, discard options dict */
+	TclEmitInstInt4(INST_REVERSE, 2, envPtr);
+	TclEmitOpcode(INST_POP, envPtr);
+
+	/*
+	 * We've emitted several POP instructions, and the automatic
+	 * computations for stack depth requirements have been decrementing
+	 * for every one.  However, we know that every branch actually taken
+	 * only encounters some of those instructions.  No branch passes
+	 * through them all.  So, we now have a stack requirements estimate
+	 * that is too low.  Here we manually fix that up.
+	 */
+	TclAdjustStackDepth(5, envPtr);
+
+	/* OK destination */
+	if (TclFixupForwardJumpToHere(envPtr, &okFixup, 127)) {
+	    Tcl_Panic("TclCompileSubstCmd: bad ok jump distance %d",
+		    CurrentOffset(envPtr) - okFixup.codeOffset);
+	}
+	if (count > 1) {
+	    TclEmitInstInt1(INST_CONCAT1, count, envPtr);
+	    count = 1;
+	}
+
+	/* CONTINUE jump to here */
+	if (TclFixupForwardJumpToHere(envPtr, &endFixup, 127)) {
+	    Tcl_Panic("TclCompileSubstCmd: bad end jump distance %d",
+		    CurrentOffset(envPtr) - endFixup.codeOffset);
+	}
+	bline = envPtr->line;
+    }
+
+
+    while (count > 255) {
+	TclEmitInstInt1(INST_CONCAT1, 255, envPtr);
+	count -= 254;
+    }
+    if (count > 1) {
+	TclEmitInstInt1(INST_CONCAT1, count, envPtr);
+    }
+
+    Tcl_FreeParse(&parse);
+
+    if (state != NULL) {
+	Tcl_RestoreInterpState(interp, state);
+	TclCompileSyntaxError(interp, envPtr);
+    }
+
+    /* Final target of the multi-jump from all BREAKs */
+    if (breakOffset > 0) {
+	TclUpdateInstInt4AtPc(INST_JUMP4, CurrentOffset(envPtr) - breakOffset,
+		envPtr->codeStart + breakOffset);
+    }
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclCompileSwitchCmd --
+ *
+ *	Procedure called to compile the "switch" command.
+ *
+ * Results:
+ *	Returns TCL_OK for successful compile, or TCL_ERROR to defer
+ *	evaluation to runtime (either when it is too complex to get the
+ *	semantics right, or when we know for sure that it is an error but need
+ *	the error to happen at the right time).
+ *
+ * Side effects:
+ *	Instructions are added to envPtr to execute the "switch" command at
+ *	runtime.
+ *
+ * FIXME:
+ *	Stack depths are probably not calculated correctly.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+TclCompileSwitchCmd(
+    Tcl_Interp *interp,		/* Used for error reporting. */
+    Tcl_Parse *parsePtr,	/* Points to a parse structure for the command
+				 * created by Tcl_ParseCommand. */
+    Command *cmdPtr,		/* Points to defintion of command being
+				 * compiled. */
+    CompileEnv *envPtr)		/* Holds resulting instructions. */
+{
+    Tcl_Token *tokenPtr;	/* Pointer to tokens in command. */
+    int numWords;		/* Number of words in command. */
+    Tcl_Token *valueTokenPtr;	/* Token for the value to switch on. */
+    enum {Switch_Exact, Switch_Glob, Switch_Regexp} mode;
+				/* What kind of switch are we doing? */
+    Tcl_Token *bodyTokenArray;	/* Array of real pattern list items. */
+    Tcl_Token **bodyToken;	/* Array of pointers to pattern list items. */
+    int *bodyLines;		/* Array of line numbers for body list
+				 * items. */
+    int **bodyContLines;	/* Array of continuation line info. */
+    int noCase;			/* Has the -nocase flag been given? */
+    int foundMode = 0;		/* Have we seen a mode flag yet? */
+    int isListedArms = 0;
+    int i, valueIndex;
+    int result = TCL_ERROR;
+    DefineLineInformation;	/* TIP #280 */
+    int *clNext = envPtr->clNext;
+
+    /*
+     * Only handle the following versions:
+     *   switch         ?--? word {pattern body ...}
+     *   switch -exact  ?--? word {pattern body ...}
+     *   switch -glob   ?--? word {pattern body ...}
+     *   switch -regexp ?--? word {pattern body ...}
+     *   switch         --   word simpleWordPattern simpleWordBody ...
+     *   switch -exact  --   word simpleWordPattern simpleWordBody ...
+     *   switch -glob   --   word simpleWordPattern simpleWordBody ...
+     *   switch -regexp --   word simpleWordPattern simpleWordBody ...
+     * When the mode is -glob, can also handle a -nocase flag.
+     *
+     * First off, we don't care how the command's word was generated; we're
+     * compiling it anyway! So skip it...
+     */
+
+    tokenPtr = TokenAfter(parsePtr->tokenPtr);
+    valueIndex = 1;
+    numWords = parsePtr->numWords-1;
+
+    /*
+     * Check for options.
+     */
+
+    noCase = 0;
+    mode = Switch_Exact;
+    if (numWords == 2) {
+	/*
+	 * There's just the switch value and the bodies list. In that case, we
+	 * can skip all option parsing and move on to consider switch values
+	 * and the body list.
+	 */
+
+	goto finishedOptionParse;
+    }
+
+    /*
+     * There must be at least one option, --, because without that there is no
+     * way to statically avoid the problems you get from strings-to-be-matched
+     * that start with a - (the interpreted code falls apart if it encounters
+     * them, so we punt if we *might* encounter them as that is the easiest
+     * way of emulating the behaviour).
+     */
+
+    for (; numWords>=3 ; tokenPtr=TokenAfter(tokenPtr),numWords--) {
+	register unsigned size = tokenPtr[1].size;
+	register const char *chrs = tokenPtr[1].start;
+
+	/*
+	 * We only process literal options, and we assume that -e, -g and -n
+	 * are unique prefixes of -exact, -glob and -nocase respectively (true
+	 * at time of writing). Note that -exact and -glob may only be given
+	 * at most once or we bail out (error case).
+	 */
+
+	if (tokenPtr->type != TCL_TOKEN_SIMPLE_WORD || size < 2) {
+	    return TCL_ERROR;
+	}
+
+	if ((size <= 6) && !memcmp(chrs, "-exact", size)) {
+	    if (foundMode) {
+		return TCL_ERROR;
+	    }
+	    mode = Switch_Exact;
+	    foundMode = 1;
+	    valueIndex++;
+	    continue;
+	} else if ((size <= 5) && !memcmp(chrs, "-glob", size)) {
+	    if (foundMode) {
+		return TCL_ERROR;
+	    }
+	    mode = Switch_Glob;
+	    foundMode = 1;
+	    valueIndex++;
+	    continue;
+	} else if ((size <= 7) && !memcmp(chrs, "-regexp", size)) {
+	    if (foundMode) {
+		return TCL_ERROR;
+	    }
+	    mode = Switch_Regexp;
+	    foundMode = 1;
+	    valueIndex++;
+	    continue;
+	} else if ((size <= 7) && !memcmp(chrs, "-nocase", size)) {
+	    noCase = 1;
+	    valueIndex++;
+	    continue;
+	} else if ((size == 2) && !memcmp(chrs, "--", 2)) {
+	    valueIndex++;
+	    break;
+	}
+
+	/*
+	 * The switch command has many flags we cannot compile at all (e.g.
+	 * all the RE-related ones) which we must have encountered. Either
+	 * that or we have run off the end. The action here is the same: punt
+	 * to interpreted version.
+	 */
+
+	return TCL_ERROR;
+    }
+    if (numWords < 3) {
+	return TCL_ERROR;
+    }
+    tokenPtr = TokenAfter(tokenPtr);
+    numWords--;
+    if (noCase && (mode == Switch_Exact)) {
+	/*
+	 * Can't compile this case; no opcode for case-insensitive equality!
+	 */
+
+	return TCL_ERROR;
+    }
+
+    /*
+     * The value to test against is going to always get pushed on the stack.
+     * But not yet; we need to verify that the rest of the command is
+     * compilable too.
+     */
+
+  finishedOptionParse:
+    valueTokenPtr = tokenPtr;
+    /* For valueIndex, see previous loop. */
+    tokenPtr = TokenAfter(tokenPtr);
+    numWords--;
+
+    /*
+     * Build an array of tokens for the matcher terms and script bodies. Note
+     * that in the case of the quoted bodies, this is tricky as we cannot use
+     * copies of the string from the input token for the generated tokens (it
+     * causes a crash during exception handling). When multiple tokens are
+     * available at this point, this is pretty easy.
+     */
+
+    if (numWords == 1) {
+	Tcl_DString bodyList;
+	const char **argv = NULL, *tokenStartPtr, *p;
+	int bline;		/* TIP #280: line of the pattern/action list,
+				 * and start of list for when tracking the
+				 * location. This list comes immediately after
+				 * the value we switch on. */
+	int isTokenBraced;
+
+	/*
+	 * Test that we've got a suitable body list as a simple (i.e. braced)
+	 * word, and that the elements of the body are simple words too. This
+	 * is really rather nasty indeed.
+	 */
+
+	if (tokenPtr->type != TCL_TOKEN_SIMPLE_WORD) {
+	    return TCL_ERROR;
+	}
+
+	Tcl_DStringInit(&bodyList);
+	Tcl_DStringAppend(&bodyList, tokenPtr[1].start, tokenPtr[1].size);
+	if (Tcl_SplitList(NULL, Tcl_DStringValue(&bodyList), &numWords,
+		&argv) != TCL_OK) {
+	    Tcl_DStringFree(&bodyList);
+	    return TCL_ERROR;
+	}
+	Tcl_DStringFree(&bodyList);
+
+	/*
+	 * Now we know what the switch arms are, we've got to see whether we
+	 * can synthesize tokens for the arms. First check whether we've got a
+	 * valid number of arms since we can do that now.
+	 */
+
+	if (numWords == 0 || numWords % 2) {
+	    ckfree((char *) argv);
+	    return TCL_ERROR;
+	}
+
+	isListedArms = 1;
+	bodyTokenArray = (Tcl_Token *) ckalloc(sizeof(Tcl_Token) * numWords);
+	bodyToken = (Tcl_Token **) ckalloc(sizeof(Tcl_Token *) * numWords);
+	bodyLines = (int *) ckalloc(sizeof(int) * numWords);
+	bodyContLines = (int **) ckalloc(sizeof(int*) * numWords);
+
+	/*
+	 * Locate the start of the arms within the overall word.
+	 */
+
+	bline = mapPtr->loc[eclIndex].line[valueIndex+1];
+	p = tokenStartPtr = tokenPtr[1].start;
+	while (isspace(UCHAR(*tokenStartPtr))) {
+	    tokenStartPtr++;
+	}
+	if (*tokenStartPtr == '{') {
+	    tokenStartPtr++;
+	    isTokenBraced = 1;
+	} else {
+	    isTokenBraced = 0;
+	}
+
+	/*
+	 * TIP #280: Count lines within the literal list.
+	 */
+
+	for (i=0 ; i<numWords ; i++) {
+	    bodyTokenArray[i].type = TCL_TOKEN_TEXT;
+	    bodyTokenArray[i].start = tokenStartPtr;
+	    bodyTokenArray[i].size = strlen(argv[i]);
+	    bodyTokenArray[i].numComponents = 0;
+	    bodyToken[i] = bodyTokenArray+i;
+	    tokenStartPtr += bodyTokenArray[i].size;
+
+	    /*
+	     * Test to see if we have guessed the end of the word correctly;
+	     * if not, we can't feed the real string to the sub-compilation
+	     * engine, and we're then stuck and so have to punt out to doing
+	     * everything at runtime.
+	     */
+
+	    if ((isTokenBraced && *(tokenStartPtr++) != '}') ||
+		    (tokenStartPtr < tokenPtr[1].start+tokenPtr[1].size
+		    && !isspace(UCHAR(*tokenStartPtr)))) {
+		ckfree((char *) argv);
+		goto freeTemporaries;
+	    }
+
+	    /*
+	     * TIP #280: Now determine the line the list element starts on
+	     * (there is no need to do it earlier, due to the possibility of
+	     * aborting, see above).
+	     */
+
+	    TclAdvanceLines(&bline, p, bodyTokenArray[i].start);
+	    TclAdvanceContinuations(&bline, &clNext,
+		    bodyTokenArray[i].start - envPtr->source);
+	    bodyLines[i] = bline;
+	    bodyContLines[i] = clNext;
+	    p = bodyTokenArray[i].start;
+
+	    while (isspace(UCHAR(*tokenStartPtr))) {
+		tokenStartPtr++;
+		if (tokenStartPtr >= tokenPtr[1].start+tokenPtr[1].size) {
+		    break;
+		}
+	    }
+	    if (*tokenStartPtr == '{') {
+		tokenStartPtr++;
+		isTokenBraced = 1;
+	    } else {
+		isTokenBraced = 0;
+	    }
+	}
+	ckfree((char *) argv);
+
+	/*
+	 * Check that we've parsed everything we thought we were going to
+	 * parse. If not, something odd is going on (I believe it is possible
+	 * to defeat the code above) and we should bail out.
+	 */
+
+	if (tokenStartPtr != tokenPtr[1].start+tokenPtr[1].size) {
+	    goto freeTemporaries;
+	}
+
+    } else if (numWords % 2 || numWords == 0) {
+	/*
+	 * Odd number of words (>1) available, or no words at all available.
+	 * Both are error cases, so punt and let the interpreted-version
+	 * generate the error message. Note that the second case probably
+	 * should get caught earlier, but it's easy to check here again anyway
+	 * because it'd cause a nasty crash otherwise.
+	 */
+
+	return TCL_ERROR;
+    } else {
+	/*
+	 * Multi-word definition of patterns & actions.
+	 */
+
+	bodyToken = (Tcl_Token **) ckalloc(sizeof(Tcl_Token *) * numWords);
+	bodyLines = (int *) ckalloc(sizeof(int) * numWords);
+	bodyContLines = (int **) ckalloc(sizeof(int*) * numWords);
+	bodyTokenArray = NULL;
+	for (i=0 ; i<numWords ; i++) {
+	    /*
+	     * We only handle the very simplest case. Anything more complex is
+	     * a good reason to go to the interpreted case anyway due to
+	     * traces, etc.
+	     */
+
+	    if (tokenPtr->type != TCL_TOKEN_SIMPLE_WORD ||
+		    tokenPtr->numComponents != 1) {
+		goto freeTemporaries;
+	    }
+	    bodyToken[i] = tokenPtr+1;
+
+	    /*
+	     * TIP #280: Copy line information from regular cmd info.
+	     */
+
+	    bodyLines[i] = mapPtr->loc[eclIndex].line[valueIndex+1+i];
+	    bodyContLines[i] = mapPtr->loc[eclIndex].next[valueIndex+1+i];
+	    tokenPtr = TokenAfter(tokenPtr);
+	}
+    }
+
+    /*
+     * Fall back to interpreted if the last body is a continuation (it's
+     * illegal, but this makes the error happen at the right time).
+     */
+
+    if (bodyToken[numWords-1]->size == 1 &&
+	    bodyToken[numWords-1]->start[0] == '-') {
+	goto freeTemporaries;
+    }
+
+    /*
+     * Now we commit to generating code; the parsing stage per se is done.
+     * Check if we can generate a jump table, since if so that's faster than
+     * doing an explicit compare with each body. Note that we're definitely
+     * over-conservative with determining whether we can do the jump table,
+     * but it handles the most common case well enough.
+     */
+
+    if ((isListedArms) && (mode == Switch_Exact) && (!noCase)) {
+	IssueSwitchJumpTable(interp, envPtr, mapPtr, eclIndex, valueIndex,
+		valueTokenPtr, numWords, bodyToken, bodyLines, bodyContLines);
+    } else {
+	IssueSwitchChainedTests(interp, envPtr, mapPtr, eclIndex, mode,noCase,
+		valueIndex, valueTokenPtr, numWords, bodyToken, bodyLines,
+		bodyContLines);
+    }
+    result = TCL_OK;
+
+    /*
+     * Clean up all our temporary space and return.
+     */
+
+  freeTemporaries:
+    ckfree((char *) bodyToken);
+    ckfree((char *) bodyLines);
+    ckfree((char *) bodyContLines);
+    if (bodyTokenArray != NULL) {
+	ckfree((char *) bodyTokenArray);
+    }
+    return result;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * IssueSwitchChainedTests --
+ *
+ *	Generate instructions for a [switch] command that is to be compiled
+ *	into a sequence of tests. This is the generic handle-everything mode
+ *	that inherently has performance that is (on average) linear in the
+ *	number of tests. It is the only mode that can handle -glob and -regexp
+ *	matches, or anything that is case-insensitive. It does not handle the
+ *	wild-and-wooly end of regexp matching (i.e., capture of match results)
+ *	so that's when we spill to the interpreted version.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static void
+IssueSwitchChainedTests(
+    Tcl_Interp *interp,		/* Context for compiling script bodies. */
+    CompileEnv *envPtr,		/* Holds resulting instructions. */
+    ExtCmdLoc *mapPtr,		/* For mapping tokens to their source code
+				 * location. */
+    int eclIndex,
+    int mode,			/* Exact, Glob or Regexp */
+    int noCase,			/* Case-insensitivity flag. */
+    int valueIndex,		/* The value to match against. */
+    Tcl_Token *valueTokenPtr,
+    int numBodyTokens,		/* Number of tokens describing things the
+				 * switch can match against and bodies to
+				 * execute when the match succeeds. */
+    Tcl_Token **bodyToken,	/* Array of pointers to pattern list items. */
+    int *bodyLines,		/* Array of line numbers for body list
+				 * items. */
+    int **bodyContLines)	/* Array of continuation line info. */
+{
+    enum {Switch_Exact, Switch_Glob, Switch_Regexp};
+    int savedStackDepth = envPtr->currStackDepth;
+    int foundDefault;		/* Flag to indicate whether a "default" clause
+				 * is present. */
+    JumpFixup *fixupArray;	/* Array of forward-jump fixup records. */
+    int *fixupTargetArray;	/* Array of places for fixups to point at. */
+    int fixupCount;		/* Number of places to fix up. */
+    int contFixIndex;		/* Where the first of the jumps due to a group
+				 * of continuation bodies starts, or -1 if
+				 * there aren't any. */
+    int contFixCount;		/* Number of continuation bodies pointing to
+				 * the current (or next) real body. */
+    int nextArmFixupIndex;
+    int simple, exact;		/* For extracting the type of regexp. */
+    int i;
+
+    /*
+     * First, we push the value we're matching against on the stack.
+     */
+
+    SetLineInformation(valueIndex);
+    CompileTokens(envPtr, valueTokenPtr, interp);
+
+    /*
+     * Generate a test for each arm.
+     */
+
+    contFixIndex = -1;
+    contFixCount = 0;
+    fixupArray = TclStackAlloc(interp, sizeof(JumpFixup) * numBodyTokens);
+    fixupTargetArray = TclStackAlloc(interp, sizeof(int) * numBodyTokens);
+    memset(fixupTargetArray, 0, numBodyTokens * sizeof(int));
+    fixupCount = 0;
+    foundDefault = 0;
+    for (i=0 ; i<numBodyTokens ; i+=2) {
+	nextArmFixupIndex = -1;
+	envPtr->currStackDepth = savedStackDepth + 1;
+	if (i!=numBodyTokens-2 || bodyToken[numBodyTokens-2]->size != 7 ||
+		memcmp(bodyToken[numBodyTokens-2]->start, "default", 7)) {
+	    /*
+	     * Generate the test for the arm.
+	     */
+
+	    switch (mode) {
+	    case Switch_Exact:
+		TclEmitOpcode(INST_DUP,				envPtr);
+		TclCompileTokens(interp, bodyToken[i], 1,	envPtr);
+		TclEmitOpcode(INST_STR_EQ,			envPtr);
+		break;
+	    case Switch_Glob:
+		TclCompileTokens(interp, bodyToken[i], 1,	envPtr);
+		TclEmitInstInt4(INST_OVER, 1,			envPtr);
+		TclEmitInstInt1(INST_STR_MATCH, noCase,		envPtr);
+		break;
+	    case Switch_Regexp:
+		simple = exact = 0;
+
+		/*
+		 * Keep in sync with TclCompileRegexpCmd.
+		 */
+
+		if (bodyToken[i]->type == TCL_TOKEN_TEXT) {
+		    Tcl_DString ds;
+
+		    if (bodyToken[i]->size == 0) {
+			/*
+			 * The semantics of regexps are that they always match
+			 * when the RE == "".
+			 */
+
+			PushLiteral(envPtr, "1", 1);
+			break;
+		    }
+
+		    /*
+		     * Attempt to convert pattern to glob. If successful, push
+		     * the converted pattern.
+		     */
+
+		    if (TclReToGlob(NULL, bodyToken[i]->start,
+			    bodyToken[i]->size, &ds, &exact) == TCL_OK) {
+			simple = 1;
+			PushLiteral(envPtr, Tcl_DStringValue(&ds),
+				Tcl_DStringLength(&ds));
+			Tcl_DStringFree(&ds);
+		    }
+		}
+		if (!simple) {
+		    TclCompileTokens(interp, bodyToken[i], 1, envPtr);
+		}
+
+		TclEmitInstInt4(INST_OVER, 1,			envPtr);
+		if (!simple) {
+		    /*
+		     * Pass correct RE compile flags. We use only Int1
+		     * (8-bit), but that handles all the flags we want to
+		     * pass. Don't use TCL_REG_NOSUB as we may have backrefs
+		     * or capture vars.
+		     */
+
+		    int cflags = TCL_REG_ADVANCED
+			    | (noCase ? TCL_REG_NOCASE : 0);
+
+		    TclEmitInstInt1(INST_REGEXP, cflags,	envPtr);
+		} else if (exact && !noCase) {
+		    TclEmitOpcode(INST_STR_EQ,			envPtr);
+		} else {
+		    TclEmitInstInt1(INST_STR_MATCH, noCase,	envPtr);
+		}
+		break;
+	    default:
+		Tcl_Panic("unknown switch mode: %d", mode);
+	    }
+
+	    /*
+	     * In a fall-through case, we will jump on _true_ to the place
+	     * where the body starts (generated later, with guarantee of this
+	     * ensured earlier; the final body is never a fall-through).
+	     */
+
+	    if (bodyToken[i+1]->size==1 && bodyToken[i+1]->start[0]=='-') {
+		if (contFixIndex == -1) {
+		    contFixIndex = fixupCount;
+		    contFixCount = 0;
+		}
+		TclEmitForwardJump(envPtr, TCL_TRUE_JUMP,
+			&fixupArray[contFixIndex+contFixCount]);
+		fixupCount++;
+		contFixCount++;
+		continue;
+	    }
+
+	    TclEmitForwardJump(envPtr, TCL_FALSE_JUMP,
+		    &fixupArray[fixupCount]);
+	    nextArmFixupIndex = fixupCount;
+	    fixupCount++;
+	} else {
+	    /*
+	     * Got a default clause; set a flag to inhibit the generation of
+	     * the jump after the body and the cleanup of the intermediate
+	     * value that we are switching against.
+	     *
+	     * Note that default clauses (which are always terminal clauses)
+	     * cannot be fall-through clauses as well, since the last clause
+	     * is never a fall-through clause (which we have already
+	     * verified).
+	     */
+
+	    foundDefault = 1;
+	}
+
+	/*
+	 * Generate the body for the arm. This is guaranteed not to be a
+	 * fall-through case, but it might have preceding fall-through cases,
+	 * so we must process those first.
+	 */
+
+	if (contFixIndex != -1) {
+	    int j;
+
+	    for (j=0 ; j<contFixCount ; j++) {
+		fixupTargetArray[contFixIndex+j] = CurrentOffset(envPtr);
+	    }
+	    contFixIndex = -1;
+	}
+
+	/*
+	 * Now do the actual compilation. Note that we do not use CompileBody
+	 * because we may have synthesized the tokens in a non-standard
+	 * pattern.
+	 */
+
+	TclEmitOpcode(INST_POP,					envPtr);
+	envPtr->currStackDepth = savedStackDepth + 1;
+	envPtr->line = bodyLines[i+1];		/* TIP #280 */
+	envPtr->clNext = bodyContLines[i+1];	/* TIP #280 */
+	TclCompileCmdWord(interp, bodyToken[i+1], 1, envPtr);
+
+	if (!foundDefault) {
+	    TclEmitForwardJump(envPtr, TCL_UNCONDITIONAL_JUMP,
+		    &fixupArray[fixupCount]);
+	    fixupCount++;
+	    fixupTargetArray[nextArmFixupIndex] = CurrentOffset(envPtr);
+	}
+    }
+
+    /*
+     * Discard the value we are matching against unless we've had a default
+     * clause (in which case it will already be gone due to the code at the
+     * start of processing an arm, guaranteed) and make the result of the
+     * command an empty string.
+     */
+
+    if (!foundDefault) {
+	TclEmitOpcode(INST_POP,					envPtr);
+	PushLiteral(envPtr, "", 0);
+    }
+
+    /*
+     * Do jump fixups for arms that were executed. First, fill in the jumps of
+     * all jumps that don't point elsewhere to point to here.
+     */
+
+    for (i=0 ; i<fixupCount ; i++) {
+	if (fixupTargetArray[i] == 0) {
+	    fixupTargetArray[i] = envPtr->codeNext-envPtr->codeStart;
+	}
+    }
+
+    /*
+     * Now scan backwards over all the jumps (all of which are forward jumps)
+     * doing each one. When we do one and there is a size changes, we must
+     * scan back over all the previous ones and see if they need adjusting
+     * before proceeding with further jump fixups (the interleaved nature of
+     * all the jumps makes this impossible to do without nested loops).
+     */
+
+    for (i=fixupCount-1 ; i>=0 ; i--) {
+	if (TclFixupForwardJump(envPtr, &fixupArray[i],
+		fixupTargetArray[i] - fixupArray[i].codeOffset, 127)) {
+	    int j;
+
+	    for (j=i-1 ; j>=0 ; j--) {
+		if (fixupTargetArray[j] > fixupArray[i].codeOffset) {
+		    fixupTargetArray[j] += 3;
+		}
+	    }
+	}
+    }
+    TclStackFree(interp, fixupTargetArray);
+    TclStackFree(interp, fixupArray);
+
+    envPtr->currStackDepth = savedStackDepth + 1;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * IssueSwitchJumpTable --
+ *
+ *	Generate instructions for a [switch] command that is to be compiled
+ *	into a jump table. This only handles the case where case-sensitive,
+ *	exact matching is used, but this is actually the most common case in
+ *	real code.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static void
+IssueSwitchJumpTable(
+    Tcl_Interp *interp,		/* Context for compiling script bodies. */
+    CompileEnv *envPtr,		/* Holds resulting instructions. */
+    ExtCmdLoc *mapPtr,		/* For mapping tokens to their source code
+				 * location. */
+    int eclIndex,
+    int valueIndex,		/* The value to match against. */
+    Tcl_Token *valueTokenPtr,
+    int numBodyTokens,		/* Number of tokens describing things the
+				 * switch can match against and bodies to
+				 * execute when the match succeeds. */
+    Tcl_Token **bodyToken,	/* Array of pointers to pattern list items. */
+    int *bodyLines,		/* Array of line numbers for body list
+				 * items. */
+    int **bodyContLines)	/* Array of continuation line info. */
+{
+    JumptableInfo *jtPtr;
+    int infoIndex, isNew, *finalFixups, numRealBodies = 0, jumpLocation;
+    int mustGenerate, foundDefault, jumpToDefault, i;
+    Tcl_DString buffer;
+    Tcl_HashEntry *hPtr;
+
+    /*
+     * First, we push the value we're matching against on the stack.
+     */
+
+    SetLineInformation(valueIndex);
+    CompileTokens(envPtr, valueTokenPtr, interp);
+
+    /*
+     * Compile the switch by using a jump table, which is basically a
+     * hashtable that maps from literal values to match against to the offset
+     * (relative to the INST_JUMP_TABLE instruction) to jump to. The jump
+     * table itself is independent of any invokation of the bytecode, and as
+     * such is stored in an auxData block.
+     *
+     * Start by allocating the jump table itself, plus some workspace.
+     */
+
+    jtPtr = (JumptableInfo *) ckalloc(sizeof(JumptableInfo));
+    Tcl_InitHashTable(&jtPtr->hashTable, TCL_STRING_KEYS);
+    infoIndex = TclCreateAuxData(jtPtr, &tclJumptableInfoType, envPtr);
+    finalFixups = TclStackAlloc(interp, sizeof(int) * (numBodyTokens/2));
+    foundDefault = 0;
+    mustGenerate = 1;
+
+    /*
+     * Next, issue the instruction to do the jump, together with what we want
+     * to do if things do not work out (jump to either the default clause or
+     * the "default" default, which just sets the result to empty). Note that
+     * we will come back and rewrite the jump's offset parameter when we know
+     * what it should be, and that all jumps we issue are of the wide kind
+     * because that makes the code much easier to debug!
+     */
+
+    jumpLocation = CurrentOffset(envPtr);
+    TclEmitInstInt4(INST_JUMP_TABLE, infoIndex,			envPtr);
+    jumpToDefault = CurrentOffset(envPtr);
+    TclEmitInstInt4(INST_JUMP4, 0,				envPtr);
+
+    for (i=0 ; i<numBodyTokens ; i+=2) {
+	/*
+	 * For each arm, we must first work out what to do with the match
+	 * term.
+	 */
+
+	if (i!=numBodyTokens-2 || bodyToken[numBodyTokens-2]->size != 7 ||
+		memcmp(bodyToken[numBodyTokens-2]->start, "default", 7)) {
+	    /*
+	     * This is not a default clause, so insert the current location as
+	     * a target in the jump table (assuming it isn't already there,
+	     * which would indicate that this clause is probably masked by an
+	     * earlier one). Note that we use a Tcl_DString here simply
+	     * because the hash API does not let us specify the string length.
+	     */
+
+	    Tcl_DStringInit(&buffer);
+	    Tcl_DStringAppend(&buffer, bodyToken[i]->start,
+		    bodyToken[i]->size);
+	    hPtr = Tcl_CreateHashEntry(&jtPtr->hashTable,
+		    Tcl_DStringValue(&buffer), &isNew);
+	    if (isNew) {
+		/*
+		 * First time we've encountered this match clause, so it must
+		 * point to here.
+		 */
+
+		Tcl_SetHashValue(hPtr, CurrentOffset(envPtr) - jumpLocation);
+	    }
+	    Tcl_DStringFree(&buffer);
+	} else {
+	    /*
+	     * This is a default clause, so patch up the fallthrough from the
+	     * INST_JUMP_TABLE instruction to here.
+	     */
+
+	    foundDefault = 1;
+	    isNew = 1;
+	    TclStoreInt4AtPtr(CurrentOffset(envPtr)-jumpToDefault,
+		    envPtr->codeStart+jumpToDefault+1);
+	}
+
+	/*
+	 * Now, for each arm we must deal with the body of the clause.
+	 *
+	 * If this is a continuation body (never true of a final clause,
+	 * whether default or not) we're done because the next jump target
+	 * will also point here, so we advance to the next clause.
+	 */
+
+	if (bodyToken[i+1]->size == 1 && bodyToken[i+1]->start[0] == '-') {
+	    mustGenerate = 1;
+	    continue;
+	}
+
+	/*
+	 * Also skip this arm if its only match clause is masked. (We could
+	 * probably be more aggressive about this, but that would be much more
+	 * difficult to get right.)
+	 */
+
+	if (!isNew && !mustGenerate) {
+	    continue;
+	}
+	mustGenerate = 0;
+
+	/*
+	 * Compile the body of the arm.
+	 */
+
+	envPtr->line = bodyLines[i+1];		/* TIP #280 */
+	envPtr->clNext = bodyContLines[i+1];	/* TIP #280 */
+	TclCompileCmdWord(interp, bodyToken[i+1], 1, envPtr);
+
+	/*
+	 * Compile a jump in to the end of the command if this body is
+	 * anything other than a user-supplied default arm (to either skip
+	 * over the remaining bodies or the code that generates an empty
+	 * result).
+	 */
+
+	if (i+2 < numBodyTokens || !foundDefault) {
+	    finalFixups[numRealBodies++] = CurrentOffset(envPtr);
+
+	    /*
+	     * Easier by far to issue this jump as a fixed-width jump, since
+	     * otherwise we'd need to do a lot more (and more awkward)
+	     * rewriting when we fixed this all up.
+	     */
+
+	    TclEmitInstInt4(INST_JUMP4, 0,			envPtr);
+	}
+    }
+
+    /*
+     * We're at the end. If we've not already done so through the processing
+     * of a user-supplied default clause, add in a "default" default clause
+     * now.
+     */
+
+    if (!foundDefault) {
+	TclStoreInt4AtPtr(CurrentOffset(envPtr)-jumpToDefault,
+		envPtr->codeStart+jumpToDefault+1);
+	PushLiteral(envPtr, "", 0);
+    }
+
+    /*
+     * No more instructions to be issued; everything that needs to jump to the
+     * end of the command is fixed up at this point.
+     */
+
+    for (i=0 ; i<numRealBodies ; i++) {
+	TclStoreInt4AtPtr(CurrentOffset(envPtr)-finalFixups[i],
+		envPtr->codeStart+finalFixups[i]+1);
+    }
+
+    /*
+     * Clean up all our temporary space and return.
+     */
+
+    TclStackFree(interp, finalFixups);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * DupJumptableInfo, FreeJumptableInfo --
+ *
+ *	Functions to duplicate, release and print a jump-table created for use
+ *	with the INST_JUMP_TABLE instruction.
+ *
+ * Results:
+ *	DupJumptableInfo: a copy of the jump-table
+ *	FreeJumptableInfo: none
+ *	PrintJumptableInfo: none
+ *
+ * Side effects:
+ *	DupJumptableInfo: allocates memory
+ *	FreeJumptableInfo: releases memory
+ *	PrintJumptableInfo: none
+ *
+ *----------------------------------------------------------------------
+ */
+
+static ClientData
+DupJumptableInfo(
+    ClientData clientData)
+{
+    JumptableInfo *jtPtr = clientData;
+    JumptableInfo *newJtPtr = (JumptableInfo *)
+	    ckalloc(sizeof(JumptableInfo));
+    Tcl_HashEntry *hPtr, *newHPtr;
+    Tcl_HashSearch search;
+    int isNew;
+
+    Tcl_InitHashTable(&newJtPtr->hashTable, TCL_STRING_KEYS);
+    hPtr = Tcl_FirstHashEntry(&jtPtr->hashTable, &search);
+    while (hPtr != NULL) {
+	newHPtr = Tcl_CreateHashEntry(&newJtPtr->hashTable,
+		Tcl_GetHashKey(&jtPtr->hashTable, hPtr), &isNew);
+	Tcl_SetHashValue(newHPtr, Tcl_GetHashValue(hPtr));
+    }
+    return newJtPtr;
+}
+
+static void
+FreeJumptableInfo(
+    ClientData clientData)
+{
+    JumptableInfo *jtPtr = clientData;
+
+    Tcl_DeleteHashTable(&jtPtr->hashTable);
+    ckfree((char *) jtPtr);
+}
+
+static void
+PrintJumptableInfo(
+    ClientData clientData,
+    Tcl_Obj *appendObj,
+    ByteCode *codePtr,
+    unsigned int pcOffset)
+{
+    register JumptableInfo *jtPtr = clientData;
+    Tcl_HashEntry *hPtr;
+    Tcl_HashSearch search;
+    const char *keyPtr;
+    int offset, i = 0;
+
+    hPtr = Tcl_FirstHashEntry(&jtPtr->hashTable, &search);
+    for (; hPtr ; hPtr = Tcl_NextHashEntry(&search)) {
+	keyPtr = Tcl_GetHashKey(&jtPtr->hashTable, hPtr);
+	offset = PTR2INT(Tcl_GetHashValue(hPtr));
+
+	if (i++) {
+	    Tcl_AppendToObj(appendObj, ", ", -1);
+	    if (i%4==0) {
+		Tcl_AppendToObj(appendObj, "\n\t\t", -1);
+	    }
+	}
+	Tcl_AppendPrintfToObj(appendObj, "\"%s\"->pc %d",
+		keyPtr, pcOffset + offset);
+    }
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclCompileTryCmd --
+ *
+ *	Procedure called to compile the "try" command.
+ *
+ * Results:
+ *	Returns TCL_OK for a successful compile. Returns TCL_ERROR to defer
+ *	evaluation to runtime.
+ *
+ * Side effects:
+ *	Instructions are added to envPtr to execute the "try" command at
+ *	runtime.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+TclCompileTryCmd(
+    Tcl_Interp *interp,		/* Used for error reporting. */
+    Tcl_Parse *parsePtr,	/* Points to a parse structure for the command
+				 * created by Tcl_ParseCommand. */
+    Command *cmdPtr,		/* Points to defintion of command being
+				 * compiled. */
+    CompileEnv *envPtr)		/* Holds resulting instructions. */
+{
+    int numWords = parsePtr->numWords, numHandlers, result = TCL_ERROR;
+    Tcl_Token *bodyToken, *finallyToken, *tokenPtr;
+    Tcl_Token **handlerTokens = NULL;
+    Tcl_Obj **matchClauses = NULL;
+    int *matchCodes=NULL, *resultVarIndices=NULL, *optionVarIndices=NULL;
+    int i;
+
+    if (numWords < 2) {
+	return TCL_ERROR;
+    }
+
+    bodyToken = TokenAfter(parsePtr->tokenPtr);
+
+    if (numWords == 2) {
+	/*
+	 * No handlers or finally; do nothing beyond evaluating the body.
+	 */
+
+	DefineLineInformation;	/* TIP #280 */
+	SetLineInformation(1);
+	CompileBody(envPtr, bodyToken, interp);
+	return TCL_OK;
+    }
+
+    numWords -= 2;
+    tokenPtr = TokenAfter(bodyToken);
+
+    /*
+     * Extract information about what handlers there are.
+     */
+
+    numHandlers = numWords >> 2;
+    numWords -= numHandlers * 4;
+    if (numHandlers > 0) {
+	handlerTokens = TclStackAlloc(interp, sizeof(Tcl_Token*)*numHandlers);
+	matchClauses = TclStackAlloc(interp, sizeof(Tcl_Obj *) * numHandlers);
+	memset(matchClauses, 0, sizeof(Tcl_Obj *) * numHandlers);
+	matchCodes = TclStackAlloc(interp, sizeof(int) * numHandlers);
+	resultVarIndices = TclStackAlloc(interp, sizeof(int) * numHandlers);
+	optionVarIndices = TclStackAlloc(interp, sizeof(int) * numHandlers);
+
+	for (i=0 ; i<numHandlers ; i++) {
+	    Tcl_Obj *tmpObj, **objv;
+	    int objc;
+
+	    if (tokenPtr->type != TCL_TOKEN_SIMPLE_WORD) {
+		goto failedToCompile;
+	    }
+	    if (tokenPtr[1].size == 4
+		    && !strncmp(tokenPtr[1].start, "trap", 4)) {
+		/*
+		 * Parse the list of errorCode words to match against.
+		 */
+
+		matchCodes[i] = TCL_ERROR;
+		tokenPtr = TokenAfter(tokenPtr);
+		TclNewObj(tmpObj);
+		Tcl_IncrRefCount(tmpObj);
+		if (!TclWordKnownAtCompileTime(tokenPtr, tmpObj)
+			|| Tcl_ListObjLength(NULL, tmpObj, &objc) != TCL_OK
+			|| (objc == 0)) {
+		    TclDecrRefCount(tmpObj);
+		    goto failedToCompile;
+		}
+		Tcl_ListObjReplace(NULL, tmpObj, 0, 0, 0, NULL);
+		matchClauses[i] = tmpObj;
+	    } else if (tokenPtr[1].size == 2
+		    && !strncmp(tokenPtr[1].start, "on", 2)) {
+		int code;
+		static const char *codes[] = {
+		    "ok", "error", "return", "break", "continue", NULL
+		};
+
+		/*
+		 * Parse the result code to look for.
+		 */
+
+		tokenPtr = TokenAfter(tokenPtr);
+		TclNewObj(tmpObj);
+		Tcl_IncrRefCount(tmpObj);
+		if (!TclWordKnownAtCompileTime(tokenPtr, tmpObj)) {
+		    TclDecrRefCount(tmpObj);
+		    goto failedToCompile;
+		}
+		if (Tcl_GetIntFromObj(NULL, tmpObj, &code) != TCL_OK
+			&& Tcl_GetIndexFromObj(NULL, tmpObj, codes, "",
+				TCL_EXACT, &code) != TCL_OK) {
+		    TclDecrRefCount(tmpObj);
+		    goto failedToCompile;
+		}
+		matchCodes[i] = code;
+		TclDecrRefCount(tmpObj);
+	    } else {
+		goto failedToCompile;
+	    }
+
+	    /*
+	     * Parse the variable binding.
+	     */
+
+	    tokenPtr = TokenAfter(tokenPtr);
+	    TclNewObj(tmpObj);
+	    Tcl_IncrRefCount(tmpObj);
+	    if (!TclWordKnownAtCompileTime(tokenPtr, tmpObj)) {
+		TclDecrRefCount(tmpObj);
+		goto failedToCompile;
+	    }
+	    if (Tcl_ListObjGetElements(NULL, tmpObj, &objc, &objv) != TCL_OK
+		    || (objc > 2)) {
+		TclDecrRefCount(tmpObj);
+		goto failedToCompile;
+	    }
+	    if (objc > 0) {
+		int len;
+		const char *varname = Tcl_GetStringFromObj(objv[0], &len);
+
+		if (!TclIsLocalScalar(varname, len)) {
+		    TclDecrRefCount(tmpObj);
+		    goto failedToCompile;
+		}
+		resultVarIndices[i] =
+			TclFindCompiledLocal(varname, len, 1, envPtr);
+	    } else {
+		resultVarIndices[i] = -1;
+	    }
+	    if (objc == 2) {
+		int len;
+		const char *varname = Tcl_GetStringFromObj(objv[1], &len);
+
+		if (!TclIsLocalScalar(varname, len)) {
+		    TclDecrRefCount(tmpObj);
+		    goto failedToCompile;
+		}
+		optionVarIndices[i] =
+			TclFindCompiledLocal(varname, len, 1, envPtr);
+	    } else {
+		optionVarIndices[i] = -1;
+	    }
+	    TclDecrRefCount(tmpObj);
+
+	    /*
+	     * Extract the body for this handler.
+	     */
+
+	    tokenPtr = TokenAfter(tokenPtr);
+	    if (tokenPtr->type != TCL_TOKEN_SIMPLE_WORD) {
+		goto failedToCompile;
+	    }
+	    if (tokenPtr[1].size == 1 && tokenPtr[1].start[0] == '-') {
+		handlerTokens[i] = NULL;
+	    } else {
+		handlerTokens[i] = tokenPtr;
+	    }
+
+	    tokenPtr = TokenAfter(tokenPtr);
+	}
+
+	if (handlerTokens[numHandlers-1] == NULL) {
+	    goto failedToCompile;
+	}
+    }
+
+    /*
+     * Parse the finally clause
+     */
+
+    if (numWords == 0) {
+	finallyToken = NULL;
+    } else if (numWords == 2) {
+	if (tokenPtr->type != TCL_TOKEN_SIMPLE_WORD || tokenPtr[1].size != 7
+		|| strncmp(tokenPtr[1].start, "finally", 7)) {
+	    goto failedToCompile;
+	}
+	finallyToken = TokenAfter(tokenPtr);
+    } else {
+	goto failedToCompile;
+    }
+
+    /*
+     * Issue the bytecode.
+     */
+
+    if (finallyToken) {
+	result = IssueTryFinallyInstructions(interp, envPtr, bodyToken,
+		numHandlers, matchCodes, matchClauses, resultVarIndices,
+		optionVarIndices, handlerTokens, finallyToken);
+    } else {
+	result = IssueTryInstructions(interp, envPtr, bodyToken, numHandlers,
+		matchCodes, matchClauses, resultVarIndices, optionVarIndices,
+		handlerTokens);
+    }
+
+    /*
+     * Delete any temporary state and finish off.
+     */
+
+  failedToCompile:
+    if (numHandlers > 0) {
+	for (i=0 ; i<numHandlers ; i++) {
+	    if (matchClauses[i]) {
+		TclDecrRefCount(matchClauses[i]);
+	    }
+	}
+	TclStackFree(interp, optionVarIndices);
+	TclStackFree(interp, resultVarIndices);
+	TclStackFree(interp, matchCodes);
+	TclStackFree(interp, matchClauses);
+	TclStackFree(interp, handlerTokens);
+    }
+    return result;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * IssueTryInstructions, IssueTryFinallyInstructions --
+ *
+ *	The code generators for [try]. Split from the parsing engine for
+ *	reasons of developer sanity, and also split between no-finally and
+ *	with-finally cases because so many of the details of generation vary
+ *	between the two.
+ *
+ *	The macros below make the instruction issuing easier to follow.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static int
+IssueTryInstructions(
+    Tcl_Interp *interp,
+    CompileEnv *envPtr,
+    Tcl_Token *bodyToken,
+    int numHandlers,
+    int *matchCodes,
+    Tcl_Obj **matchClauses,
+    int *resultVars,
+    int *optionVars,
+    Tcl_Token **handlerTokens)
+{
+    DefineLineInformation;	/* TIP #280 */
+    int range, resultVar, optionsVar;
+    int i, j, len, forwardsNeedFixing = 0;
+    int *addrsToFix, *forwardsToFix, notCodeJumpSource, notECJumpSource;
+    char buf[TCL_INTEGER_SPACE];
+
+    resultVar = TclFindCompiledLocal(NULL, 0, 1, envPtr);
+    optionsVar = TclFindCompiledLocal(NULL, 0, 1, envPtr);
+    if (resultVar < 0 || optionsVar < 0) {
+	return TCL_ERROR;
+    }
+
+    /*
+     * Compile the body, trapping any error in it so that we can trap on it
+     * and/or run a finally clause. Note that there must be at least one
+     * on/trap clause; when none is present, this whole function is not called
+     * (and it's never called when there's a finally clause).
+     */
+
+    range = DeclareExceptionRange(envPtr, CATCH_EXCEPTION_RANGE);
+    OP4(				BEGIN_CATCH4, range);
+    ExceptionRangeStarts(envPtr, range);
+    BODY(				bodyToken, 1);
+    ExceptionRangeEnds(envPtr, range);
+    OP1(				JUMP1, 3);
+    ExceptionRangeTarget(envPtr, range, catchOffset);
+    OP(					PUSH_RESULT);
+    OP4(				STORE_SCALAR4, resultVar);
+    OP(					POP);
+    OP(					PUSH_RETURN_OPTIONS);
+    OP4(				STORE_SCALAR4, optionsVar);
+    OP(					POP);
+    OP(					PUSH_RETURN_CODE);
+    OP(					END_CATCH);
+
+    /*
+     * Now we handle all the registered 'on' and 'trap' handlers in order.
+     * For us to be here, there must be at least one handler.
+     *
+     * Slight overallocation, but reduces size of this function.
+     */
+
+    addrsToFix = TclStackAlloc(interp, sizeof(int)*numHandlers);
+    forwardsToFix = TclStackAlloc(interp, sizeof(int)*numHandlers);
+
+    for (i=0 ; i<numHandlers ; i++) {
+	sprintf(buf, "%d", matchCodes[i]);
+	OP(				DUP);
+	PUSH(				buf);
+	OP(				EQ);
+	JUMP(notCodeJumpSource,		JUMP_FALSE4);
+	if (matchClauses[i]) {
+	    Tcl_ListObjLength(NULL, matchClauses[i], &len);
+
+	    /*
+	     * Match the errorcode according to try/trap rules.
+	     */
+
+	    OP4(			LOAD_SCALAR4, optionsVar);
+	    PUSH(			"-errorcode");
+	    OP4(			DICT_GET, 1);
+	    OP44(			LIST_RANGE_IMM, 0, len-1);
+	    PUSH(			TclGetString(matchClauses[i]));
+	    OP(				STR_EQ);
+	    JUMP(notECJumpSource,	JUMP_FALSE4);
+	} else {
+	    notECJumpSource = -1; /* LINT */
+	}
+	OP(				POP);
+
+	/*
+	 * There is no finally clause, so we can avoid wrapping a catch
+	 * context around the handler. That simplifies what instructions need
+	 * to be issued a lot since we can let errors just fall through.
+	 */
+
+	if (resultVars[i] >= 0) {
+	    OP4(			LOAD_SCALAR4, resultVar);
+	    OP4(			STORE_SCALAR4, resultVars[i]);
+	    OP(				POP);
+	    if (optionVars[i] >= 0) {
+		OP4(			LOAD_SCALAR4, optionsVar);
+		OP4(			STORE_SCALAR4, optionVars[i]);
+		OP(			POP);
+	    }
+	}
+	if (!handlerTokens[i]) {
+	    forwardsNeedFixing = 1;
+	    JUMP(forwardsToFix[i],	JUMP4);
+	} else {
+	    forwardsToFix[i] = -1;
+	    if (forwardsNeedFixing) {
+		forwardsNeedFixing = 0;
+		for (j=0 ; j<i ; j++) {
+		    if (forwardsToFix[j] == -1) {
+			continue;
+		    }
+		    FIXJUMP(forwardsToFix[j]);
+		    forwardsToFix[j] = -1;
+		}
+	    }
+	    BODY(			handlerTokens[i], 5+i*4);
+	}
+
+	JUMP(addrsToFix[i],		JUMP4);
+	if (matchClauses[i]) {
+	    FIXJUMP(notECJumpSource);
+	}
+	FIXJUMP(notCodeJumpSource);
+    }
+
+    /*
+     * Drop the result code since it didn't match any clause, and reissue the
+     * exception. Note also that INST_RETURN_STK can proceed to the next
+     * instruction.
+     */
+
+    OP(					POP);
+    OP4(				LOAD_SCALAR4, optionsVar);
+    OP4(				LOAD_SCALAR4, resultVar);
+    OP(					RETURN_STK);
+
+    /*
+     * Fix all the jumps from taken clauses to here (which is the end of the
+     * [try]).
+     */
+
+    for (i=0 ; i<numHandlers ; i++) {
+	FIXJUMP(addrsToFix[i]);
+    }
+    TclStackFree(interp, forwardsToFix);
+    TclStackFree(interp, addrsToFix);
+    return TCL_OK;
+}
+
+static int
+IssueTryFinallyInstructions(
+    Tcl_Interp *interp,
+    CompileEnv *envPtr,
+    Tcl_Token *bodyToken,
+    int numHandlers,
+    int *matchCodes,
+    Tcl_Obj **matchClauses,
+    int *resultVars,
+    int *optionVars,
+    Tcl_Token **handlerTokens,
+    Tcl_Token *finallyToken)	/* Not NULL */
+{
+    DefineLineInformation;	/* TIP #280 */
+    int savedStackDepth = envPtr->currStackDepth;
+    int range, resultVar, optionsVar, i, j, len, forwardsNeedFixing = 0;
+    int *addrsToFix, *forwardsToFix, notCodeJumpSource, notECJumpSource;
+    char buf[TCL_INTEGER_SPACE];
+
+    resultVar = TclFindCompiledLocal(NULL, 0, 1, envPtr);
+    optionsVar = TclFindCompiledLocal(NULL, 0, 1, envPtr);
+    if (resultVar < 0 || optionsVar < 0) {
+	return TCL_ERROR;
+    }
+
+    /*
+     * Compile the body, trapping any error in it so that we can trap on it
+     * (if any trap matches) and run a finally clause.
+     */
+
+    range = DeclareExceptionRange(envPtr, CATCH_EXCEPTION_RANGE);
+    OP4(				BEGIN_CATCH4, range);
+    ExceptionRangeStarts(envPtr, range);
+    BODY(				bodyToken, 1);
+    ExceptionRangeEnds(envPtr, range);
+    OP1(				JUMP1, 3);
+    ExceptionRangeTarget(envPtr, range, catchOffset);
+    OP(					PUSH_RESULT);
+    OP4(				STORE_SCALAR4, resultVar);
+    OP(					POP);
+    OP(					PUSH_RETURN_OPTIONS);
+    OP4(				STORE_SCALAR4, optionsVar);
+    OP(					POP);
+    OP(					PUSH_RETURN_CODE);
+    OP(					END_CATCH);
+    envPtr->currStackDepth = savedStackDepth + 1;
+
+    /*
+     * Now we handle all the registered 'on' and 'trap' handlers in order.
+     */
+
+    if (numHandlers) {
+	/*
+	 * Slight overallocation, but reduces size of this function.
+	 */
+
+	addrsToFix = TclStackAlloc(interp, sizeof(int)*numHandlers);
+	forwardsToFix = TclStackAlloc(interp, sizeof(int)*numHandlers);
+
+	for (i=0 ; i<numHandlers ; i++) {
+	    sprintf(buf, "%d", matchCodes[i]);
+	    OP(				DUP);
+	    PUSH(			buf);
+	    OP(				EQ);
+	    JUMP(notCodeJumpSource,	JUMP_FALSE4);
+	    if (matchClauses[i]) {
+		Tcl_ListObjLength(NULL, matchClauses[i], &len);
+
+		/*
+		 * Match the errorcode according to try/trap rules.
+		 */
+
+		OP4(			LOAD_SCALAR4, optionsVar);
+		PUSH(			"-errorcode");
+		OP4(			DICT_GET, 1);
+		OP44(			LIST_RANGE_IMM, 0, len-1);
+		PUSH(			TclGetString(matchClauses[i]));
+		OP(			STR_EQ);
+		JUMP(notECJumpSource,	JUMP_FALSE4);
+	    } else {
+		notECJumpSource = -1; /* LINT */
+	    }
+
+	    /*
+	     * There is a finally clause, so we need a fairly complex sequence
+	     * of instructions to deal with an on/trap handler because we must
+	     * call the finally handler *and* we need to substitute the result
+	     * from a failed trap for the result from the main script.
+	     */
+
+	    if (resultVars[i] >= 0 || handlerTokens[i]) {
+		range = DeclareExceptionRange(envPtr, CATCH_EXCEPTION_RANGE);
+		OP4(			BEGIN_CATCH4, range);
+		ExceptionRangeStarts(envPtr, range);
+	    }
+	    if (resultVars[i] >= 0) {
+		OP4(			LOAD_SCALAR4, resultVar);
+		OP4(			STORE_SCALAR4, resultVars[i]);
+		OP(			POP);
+		if (optionVars[i] >= 0) {
+		    OP4(		LOAD_SCALAR4, optionsVar);
+		    OP4(		STORE_SCALAR4, optionVars[i]);
+		    OP(			POP);
+		}
+	    }
+	    if (!handlerTokens[i]) {
+		/*
+		 * No handler. Will not be the last handler (that condition is
+		 * checked by the caller). Chain to the next one.
+		 */
+
+		ExceptionRangeEnds(envPtr, range);
+		forwardsNeedFixing = 1;
+		JUMP(forwardsToFix[i],	JUMP4);
+		if (resultVars[i] >= 0) {
+		    goto finishTrapCatchHandling;
+		}
+	    } else {
+		/*
+		 * Got a handler. Make sure that any pending patch-up actions
+		 * from previous unprocessed handlers are dealt with now that
+		 * we know where they are to jump to.
+		 */
+
+		if (forwardsNeedFixing) {
+		    forwardsNeedFixing = 0;
+		    OP1(		JUMP1, 7);
+		    for (j=0 ; j<i ; j++) {
+			if (forwardsToFix[j] == -1) {
+			    continue;
+			}
+			FIXJUMP(forwardsToFix[j]);
+			forwardsToFix[j] = -1;
+		    }
+		    OP4(		BEGIN_CATCH4, range);
+		}
+		BODY(			handlerTokens[i], 5+i*4);
+		ExceptionRangeEnds(envPtr, range);
+		OP(			POP);
+		OP1(			JUMP1, 6);
+		forwardsToFix[i] = -1;
+
+		/*
+		 * Error in handler or setting of variables; replace the
+		 * stored exception with the new one. Note that we only push
+		 * this if we have either a body or some variable setting
+		 * here. Otherwise this code is unreachable.
+		 */
+
+	    finishTrapCatchHandling:
+		ExceptionRangeTarget(envPtr, range, catchOffset);
+		OP(			PUSH_RESULT);
+		OP4(			STORE_SCALAR4, resultVar);
+		OP(			POP);
+		OP(			PUSH_RETURN_OPTIONS);
+		OP4(			STORE_SCALAR4, optionsVar);
+		OP(			POP);
+		OP(			END_CATCH);
+	    }
+	    if (i+1 < numHandlers) {
+		JUMP(addrsToFix[i],	JUMP4);
+	    }
+	    if (matchClauses[i]) {
+		FIXJUMP(notECJumpSource);
+	    }
+	    FIXJUMP(notCodeJumpSource);
+	}
+
+	/*
+	 * Fix all the jumps from taken clauses to here (the start of the
+	 * finally clause).
+	 */
+
+	for (i=0 ; i<numHandlers-1 ; i++) {
+	    FIXJUMP(addrsToFix[i]);
+	}
+	TclStackFree(interp, forwardsToFix);
+	TclStackFree(interp, addrsToFix);
+    }
+
+    /*
+     * Drop the result code.
+     */
+
+    OP(					POP);
+    envPtr->currStackDepth = savedStackDepth;
+
+    /*
+     * Process the finally clause (at last!) Note that we do not wrap this in
+     * error handlers because we would just rethrow immediately anyway. Then
+     * (on normal success) we reissue the exception. Note also that
+     * INST_RETURN_STK can proceed to the next instruction; that'll be the
+     * next command (or some inter-command manipulation).
+     */
+
+    BODY(				finallyToken, 3 + 4*numHandlers);
+    OP(					POP);
+    OP4(				LOAD_SCALAR4, optionsVar);
+    OP4(				LOAD_SCALAR4, resultVar);
+    OP(					RETURN_STK);
+
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclCompileUnsetCmd --
+ *
+ *	Procedure called to compile the "unset" command.
+ *
+ * Results:
+ *	Returns TCL_OK for a successful compile. Returns TCL_ERROR to defer
+ *	evaluation to runtime.
+ *
+ * Side effects:
+ *	Instructions are added to envPtr to execute the "unset" command at
+ *	runtime.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+TclCompileUnsetCmd(
+    Tcl_Interp *interp,		/* Used for error reporting. */
+    Tcl_Parse *parsePtr,	/* Points to a parse structure for the command
+				 * created by Tcl_ParseCommand. */
+    Command *cmdPtr,		/* Points to defintion of command being
+				 * compiled. */
+    CompileEnv *envPtr)		/* Holds resulting instructions. */
+{
+    Tcl_Token *varTokenPtr;
+    int isScalar, simpleVarName, localIndex, numWords, flags, i;
+    Tcl_Obj *leadingWord;
+    DefineLineInformation;	/* TIP #280 */
+
+    numWords = parsePtr->numWords-1;
+    flags = 1;
+    varTokenPtr = TokenAfter(parsePtr->tokenPtr);
+    leadingWord = Tcl_NewObj();
+    if (TclWordKnownAtCompileTime(varTokenPtr, leadingWord)) {
+	int len;
+	const char *bytes = Tcl_GetStringFromObj(leadingWord, &len);
+
+	if (len == 11 && !strncmp("-nocomplain", bytes, 11)) {
+	    flags = 0;
+	    varTokenPtr = TokenAfter(varTokenPtr);
+	    numWords--;
+	} else if (len == 2 && !strncmp("--", bytes, 2)) {
+	    varTokenPtr = TokenAfter(varTokenPtr);
+	    numWords--;
+	}
+    } else {
+	/*
+	 * Cannot guarantee that the first word is not '-nocomplain' at
+	 * evaluation with reasonable effort, so spill to interpreted version.
+	 */
+
+	return TCL_ERROR;
+    }
+    TclDecrRefCount(leadingWord);
+
+    for (i=0 ; i<numWords ; i++) {
+	/*
+	 * Decide if we can use a frame slot for the var/array name or if we
+	 * need to emit code to compute and push the name at runtime. We use a
+	 * frame slot (entry in the array of local vars) if we are compiling a
+	 * procedure body and if the name is simple text that does not include
+	 * namespace qualifiers.
+	 */
+
+	PushVarNameWord(interp, varTokenPtr, envPtr, 0,
+		&localIndex, &simpleVarName, &isScalar, 1);
+
+	/*
+	 * Emit instructions to unset the variable.
+	 */
+
+	if (!simpleVarName) {
+	    TclEmitInstInt1(	INST_UNSET_STK, flags,		envPtr);
+	} else if (isScalar) {
+	    if (localIndex < 0) {
+		TclEmitInstInt1(INST_UNSET_STK, flags,		envPtr);
+	    } else {
+		TclEmitInstInt1(INST_UNSET_SCALAR, flags,	envPtr);
+		TclEmitInt4(			   localIndex,	envPtr);
+	    }
+	} else {
+	    if (localIndex < 0) {
+		TclEmitInstInt1(INST_UNSET_ARRAY_STK, flags,	envPtr);
+	    } else {
+		TclEmitInstInt1(INST_UNSET_ARRAY, flags,	envPtr);
+		TclEmitInt4(			  localIndex,	envPtr);
+	    }
+	}
+
+	varTokenPtr = TokenAfter(varTokenPtr);
+    }
+    PushLiteral(envPtr, "", 0);
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclCompileWhileCmd --
+ *
+ *	Procedure called to compile the "while" command.
+ *
+ * Results:
+ *	Returns TCL_OK for a successful compile. Returns TCL_ERROR to defer
+ *	evaluation to runtime.
+ *
+ * Side effects:
+ *	Instructions are added to envPtr to execute the "while" command at
+ *	runtime.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+TclCompileWhileCmd(
+    Tcl_Interp *interp,		/* Used for error reporting. */
+    Tcl_Parse *parsePtr,	/* Points to a parse structure for the command
+				 * created by Tcl_ParseCommand. */
+    Command *cmdPtr,		/* Points to defintion of command being
+				 * compiled. */
+    CompileEnv *envPtr)		/* Holds resulting instructions. */
+{
+    Tcl_Token *testTokenPtr, *bodyTokenPtr;
+    JumpFixup jumpEvalCondFixup;
+    int testCodeOffset, bodyCodeOffset, jumpDist, range, code, boolVal;
+    int savedStackDepth = envPtr->currStackDepth;
+    int loopMayEnd = 1;		/* This is set to 0 if it is recognized as an
+				 * infinite loop. */
+    Tcl_Obj *boolObj;
+    DefineLineInformation;	/* TIP #280 */
+
+    if (parsePtr->numWords != 3) {
+	return TCL_ERROR;
+    }
+
+    /*
+     * If the test expression requires substitutions, don't compile the while
+     * command inline. E.g., the expression might cause the loop to never
+     * execute or execute forever, as in "while "$x < 5" {}".
+     *
+     * Bail out also if the body expression requires substitutions in order to
+     * insure correct behaviour [Bug 219166]
+     */
+
+    testTokenPtr = TokenAfter(parsePtr->tokenPtr);
+    bodyTokenPtr = TokenAfter(testTokenPtr);
+
+    if ((testTokenPtr->type != TCL_TOKEN_SIMPLE_WORD)
+	    || (bodyTokenPtr->type != TCL_TOKEN_SIMPLE_WORD)) {
+	return TCL_ERROR;
+    }
+
+    /*
+     * Find out if the condition is a constant.
+     */
+
+    boolObj = Tcl_NewStringObj(testTokenPtr[1].start, testTokenPtr[1].size);
+    Tcl_IncrRefCount(boolObj);
+    code = Tcl_GetBooleanFromObj(NULL, boolObj, &boolVal);
+    TclDecrRefCount(boolObj);
+    if (code == TCL_OK) {
+	if (boolVal) {
+	    /*
+	     * It is an infinite loop; flag it so that we generate a more
+	     * efficient body.
+	     */
+
+	    loopMayEnd = 0;
+	} else {
+	    /*
+	     * This is an empty loop: "while 0 {...}" or such. Compile no
+	     * bytecodes.
+	     */
+
+	    goto pushResult;
+	}
+    }
+
+    /*
+     * Create a ExceptionRange record for the loop body. This is used to
+     * implement break and continue.
+     */
+
+    range = DeclareExceptionRange(envPtr, LOOP_EXCEPTION_RANGE);
+
+    /*
+     * Jump to the evaluation of the condition. This code uses the "loop
+     * rotation" optimisation (which eliminates one branch from the loop).
+     * "while cond body" produces then:
+     *       goto A
+     *    B: body                : bodyCodeOffset
+     *    A: cond -> result      : testCodeOffset, continueOffset
+     *       if (result) goto B
+     *
+     * The infinite loop "while 1 body" produces:
+     *    B: body                : all three offsets here
+     *       goto B
+     */
+
+    if (loopMayEnd) {
+	TclEmitForwardJump(envPtr, TCL_UNCONDITIONAL_JUMP,
+		&jumpEvalCondFixup);
+	testCodeOffset = 0;	/* Avoid compiler warning. */
+    } else {
+	/*
+	 * Make sure that the first command in the body is preceded by an
+	 * INST_START_CMD, and hence counted properly. [Bug 1752146]
+	 */
+
+	envPtr->atCmdStart = 0;
+	testCodeOffset = CurrentOffset(envPtr);
+    }
+
+    /*
+     * Compile the loop body.
+     */
+
+    SetLineInformation(2);
+    bodyCodeOffset = ExceptionRangeStarts(envPtr, range);
+    CompileBody(envPtr, bodyTokenPtr, interp);
+    ExceptionRangeEnds(envPtr, range);
+    envPtr->currStackDepth = savedStackDepth + 1;
+    TclEmitOpcode(INST_POP, envPtr);
+
+    /*
+     * Compile the test expression then emit the conditional jump that
+     * terminates the while. We already know it's a simple word.
+     */
+
+    if (loopMayEnd) {
+	testCodeOffset = CurrentOffset(envPtr);
+	jumpDist = testCodeOffset - jumpEvalCondFixup.codeOffset;
+	if (TclFixupForwardJump(envPtr, &jumpEvalCondFixup, jumpDist, 127)) {
+	    bodyCodeOffset += 3;
+	    testCodeOffset += 3;
+	}
+	envPtr->currStackDepth = savedStackDepth;
+	SetLineInformation(1);
+	TclCompileExprWords(interp, testTokenPtr, 1, envPtr);
+	envPtr->currStackDepth = savedStackDepth + 1;
+
+	jumpDist = CurrentOffset(envPtr) - bodyCodeOffset;
+	if (jumpDist > 127) {
+	    TclEmitInstInt4(INST_JUMP_TRUE4, -jumpDist, envPtr);
+	} else {
+	    TclEmitInstInt1(INST_JUMP_TRUE1, -jumpDist, envPtr);
+	}
+    } else {
+	jumpDist = CurrentOffset(envPtr) - bodyCodeOffset;
+	if (jumpDist > 127) {
+	    TclEmitInstInt4(INST_JUMP4, -jumpDist, envPtr);
+	} else {
+	    TclEmitInstInt1(INST_JUMP1, -jumpDist, envPtr);
+	}
+    }
+
+    /*
+     * Set the loop's body, continue and break offsets.
+     */
+
+    envPtr->exceptArrayPtr[range].continueOffset = testCodeOffset;
+    envPtr->exceptArrayPtr[range].codeOffset = bodyCodeOffset;
+    ExceptionRangeTarget(envPtr, range, breakOffset);
+
+    /*
+     * The while command's result is an empty string.
+     */
+
+  pushResult:
+    envPtr->currStackDepth = savedStackDepth;
+    PushLiteral(envPtr, "", 0);
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * PushVarName --
+ *
+ *	Procedure used in the compiling where pushing a variable name is
+ *	necessary (append, lappend, set).
+ *
+ * Results:
+ *	Returns TCL_OK for a successful compile. Returns TCL_ERROR to defer
+ *	evaluation to runtime.
+ *
+ * Side effects:
+ *	Instructions are added to envPtr to execute the "set" command at
+ *	runtime.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static int
+PushVarName(
+    Tcl_Interp *interp,		/* Used for error reporting. */
+    Tcl_Token *varTokenPtr,	/* Points to a variable token. */
+    CompileEnv *envPtr,		/* Holds resulting instructions. */
+    int flags,			/* TCL_NO_LARGE_INDEX. */
+    int *localIndexPtr,		/* Must not be NULL. */
+    int *simpleVarNamePtr,	/* Must not be NULL. */
+    int *isScalarPtr,		/* Must not be NULL. */
+    int line,			/* Line the token starts on. */
+    int *clNext)		/* Reference to offset of next hidden cont.
+				 * line. */
+{
+    register const char *p;
+    const char *name, *elName;
+    register int i, n;
+    Tcl_Token *elemTokenPtr = NULL;
+    int nameChars, elNameChars, simpleVarName, localIndex;
+    int elemTokenCount = 0, allocedTokens = 0, removedParen = 0;
+
+    /*
+     * Decide if we can use a frame slot for the var/array name or if we need
+     * to emit code to compute and push the name at runtime. We use a frame
+     * slot (entry in the array of local vars) if we are compiling a procedure
+     * body and if the name is simple text that does not include namespace
+     * qualifiers.
+     */
+
+    simpleVarName = 0;
+    name = elName = NULL;
+    nameChars = elNameChars = 0;
+    localIndex = -1;
+
+    /*
+     * Check not only that the type is TCL_TOKEN_SIMPLE_WORD, but whether
+     * curly braces surround the variable name. This really matters for array
+     * elements to handle things like
+     *    set {x($foo)} 5
+     * which raises an undefined var error if we are not careful here.
+     */
+
+    if ((varTokenPtr->type == TCL_TOKEN_SIMPLE_WORD) &&
+	    (varTokenPtr->start[0] != '{')) {
+	/*
+	 * A simple variable name. Divide it up into "name" and "elName"
+	 * strings. If it is not a local variable, look it up at runtime.
+	 */
+
+	simpleVarName = 1;
+
+	name = varTokenPtr[1].start;
+	nameChars = varTokenPtr[1].size;
+	if (name[nameChars-1] == ')') {
+	    /*
+	     * last char is ')' => potential array reference.
+	     */
+
+	    for (i=0,p=name ; i<nameChars ; i++,p++) {
+		if (*p == '(') {
+		    elName = p + 1;
+		    elNameChars = nameChars - i - 2;
+		    nameChars = i;
+		    break;
+		}
+	    }
+
+	    if ((elName != NULL) && elNameChars) {
+		/*
+		 * An array element, the element name is a simple string:
+		 * assemble the corresponding token.
+		 */
+
+		elemTokenPtr = TclStackAlloc(interp, sizeof(Tcl_Token));
+		allocedTokens = 1;
+		elemTokenPtr->type = TCL_TOKEN_TEXT;
+		elemTokenPtr->start = elName;
+		elemTokenPtr->size = elNameChars;
+		elemTokenPtr->numComponents = 0;
+		elemTokenCount = 1;
+	    }
+	}
+    } else if (((n = varTokenPtr->numComponents) > 1)
+	    && (varTokenPtr[1].type == TCL_TOKEN_TEXT)
+	    && (varTokenPtr[n].type == TCL_TOKEN_TEXT)
+	    && (varTokenPtr[n].start[varTokenPtr[n].size - 1] == ')')) {
+	/*
+	 * Check for parentheses inside first token.
+	 */
+
+	simpleVarName = 0;
+	for (i = 0, p = varTokenPtr[1].start;
+		i < varTokenPtr[1].size; i++, p++) {
+	    if (*p == '(') {
+		simpleVarName = 1;
+		break;
+	    }
+	}
+	if (simpleVarName) {
+	    int remainingChars;
+
+	    /*
+	     * Check the last token: if it is just ')', do not count it.
+	     * Otherwise, remove the ')' and flag so that it is restored at
+	     * the end.
+	     */
+
+	    if (varTokenPtr[n].size == 1) {
+		--n;
+	    } else {
+		--varTokenPtr[n].size;
+		removedParen = n;
+	    }
+
+	    name = varTokenPtr[1].start;
+	    nameChars = p - varTokenPtr[1].start;
+	    elName = p + 1;
+	    remainingChars = (varTokenPtr[2].start - p) - 1;
+	    elNameChars = (varTokenPtr[n].start-p) + varTokenPtr[n].size - 2;
+
+	    if (remainingChars) {
+		/*
+		 * Make a first token with the extra characters in the first
+		 * token.
+		 */
+
+		elemTokenPtr = TclStackAlloc(interp, n * sizeof(Tcl_Token));
+		allocedTokens = 1;
+		elemTokenPtr->type = TCL_TOKEN_TEXT;
+		elemTokenPtr->start = elName;
+		elemTokenPtr->size = remainingChars;
+		elemTokenPtr->numComponents = 0;
+		elemTokenCount = n;
+
+		/*
+		 * Copy the remaining tokens.
+		 */
+
+		memcpy(elemTokenPtr+1, varTokenPtr+2,
+			(n-1) * sizeof(Tcl_Token));
+	    } else {
+		/*
+		 * Use the already available tokens.
+		 */
+
+		elemTokenPtr = &varTokenPtr[2];
+		elemTokenCount = n - 1;
+	    }
+	}
+    }
+
+    if (simpleVarName) {
+	/*
+	 * See whether name has any namespace separators (::'s).
+	 */
+
+	int hasNsQualifiers = 0;
+
+	for (i = 0, p = name;  i < nameChars;  i++, p++) {
+	    if ((*p == ':') && ((i+1) < nameChars) && (*(p+1) == ':')) {
+		hasNsQualifiers = 1;
+		break;
+	    }
+	}
+
+	/*
+	 * Look up the var name's index in the array of local vars in the proc
+	 * frame. If retrieving the var's value and it doesn't already exist,
+	 * push its name and look it up at runtime.
+	 */
+
+	if (!hasNsQualifiers) {
+	    localIndex = TclFindCompiledLocal(name, nameChars,
+		    1, envPtr);
+	    if ((flags & TCL_NO_LARGE_INDEX) && (localIndex > 255)) {
+		/*
+		 * We'll push the name.
+		 */
+
+		localIndex = -1;
+	    }
+	}
+	if (localIndex < 0) {
+	    PushLiteral(envPtr, name, nameChars);
+	}
+
+	/*
+	 * Compile the element script, if any.
+	 */
+
+	if (elName != NULL) {
+	    if (elNameChars) {
+		envPtr->line = line;
+		envPtr->clNext = clNext;
+		TclCompileTokens(interp, elemTokenPtr, elemTokenCount,
+			envPtr);
+	    } else {
+		PushLiteral(envPtr, "", 0);
+	    }
+	}
+    } else {
+	/*
+	 * The var name isn't simple: compile and push it.
+	 */
+
+	envPtr->line = line;
+	envPtr->clNext = clNext;
+	CompileTokens(envPtr, varTokenPtr, interp);
+    }
+
+    if (removedParen) {
+	++varTokenPtr[removedParen].size;
+    }
+    if (allocedTokens) {
+	TclStackFree(interp, elemTokenPtr);
+    }
+    *localIndexPtr = localIndex;
+    *simpleVarNamePtr = simpleVarName;
+    *isScalarPtr = (elName == NULL);
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * CompileUnaryOpCmd --
+ *
+ *	Utility routine to compile the unary operator commands.
+ *
+ * Results:
+ *	Returns TCL_OK for a successful compile. Returns TCL_ERROR to defer
+ *	evaluation to runtime.
+ *
+ * Side effects:
+ *	Instructions are added to envPtr to execute the compiled command at
+ *	runtime.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static int
+CompileUnaryOpCmd(
+    Tcl_Interp *interp,
+    Tcl_Parse *parsePtr,
+    int instruction,
+    CompileEnv *envPtr)
+{
+    Tcl_Token *tokenPtr;
+    DefineLineInformation;	/* TIP #280 */
+
+    if (parsePtr->numWords != 2) {
+	return TCL_ERROR;
+    }
+    tokenPtr = TokenAfter(parsePtr->tokenPtr);
+    CompileWord(envPtr, tokenPtr, interp, 1);
+    TclEmitOpcode(instruction, envPtr);
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * CompileAssociativeBinaryOpCmd --
+ *
+ *	Utility routine to compile the binary operator commands that accept an
+ *	arbitrary number of arguments, and that are associative operations.
+ *	Because of the associativity, we may combine operations from right to
+ *	left, saving us any effort of re-ordering the arguments on the stack
+ *	after substitutions are completed.
+ *
+ * Results:
+ *	Returns TCL_OK for a successful compile. Returns TCL_ERROR to defer
+ *	evaluation to runtime.
+ *
+ * Side effects:
+ *	Instructions are added to envPtr to execute the compiled command at
+ *	runtime.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static int
+CompileAssociativeBinaryOpCmd(
+    Tcl_Interp *interp,
+    Tcl_Parse *parsePtr,
+    const char *identity,
+    int instruction,
+    CompileEnv *envPtr)
+{
+    Tcl_Token *tokenPtr = parsePtr->tokenPtr;
+    DefineLineInformation;	/* TIP #280 */
+    int words;
+
+    for (words=1 ; words<parsePtr->numWords ; words++) {
+	tokenPtr = TokenAfter(tokenPtr);
+	CompileWord(envPtr, tokenPtr, interp, words);
+    }
+    if (parsePtr->numWords <= 2) {
+	PushLiteral(envPtr, identity, -1);
+	words++;
+    }
+    if (words > 3) {
+	/*
+	 * Reverse order of arguments to get precise agreement with [expr] in
+	 * calcuations, including roundoff errors.
+	 */
+
+	TclEmitInstInt4(INST_REVERSE, words-1, envPtr);
+    }
+    while (--words > 1) {
+	TclEmitOpcode(instruction, envPtr);
+    }
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * CompileStrictlyBinaryOpCmd --
+ *
+ *	Utility routine to compile the binary operator commands, that strictly
+ *	accept exactly two arguments.
+ *
+ * Results:
+ *	Returns TCL_OK for a successful compile. Returns TCL_ERROR to defer
+ *	evaluation to runtime.
+ *
+ * Side effects:
+ *	Instructions are added to envPtr to execute the compiled command at
+ *	runtime.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static int
+CompileStrictlyBinaryOpCmd(
+    Tcl_Interp *interp,
+    Tcl_Parse *parsePtr,
+    int instruction,
+    CompileEnv *envPtr)
+{
+    if (parsePtr->numWords != 3) {
+	return TCL_ERROR;
+    }
+    return CompileAssociativeBinaryOpCmd(interp, parsePtr,
+	    NULL, instruction, envPtr);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * CompileComparisonOpCmd --
+ *
+ *	Utility routine to compile the n-ary comparison operator commands.
+ *
+ * Results:
+ *	Returns TCL_OK for a successful compile. Returns TCL_ERROR to defer
+ *	evaluation to runtime.
+ *
+ * Side effects:
+ *	Instructions are added to envPtr to execute the compiled command at
+ *	runtime.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static int
+CompileComparisonOpCmd(
+    Tcl_Interp *interp,
+    Tcl_Parse *parsePtr,
+    int instruction,
+    CompileEnv *envPtr)
+{
+    Tcl_Token *tokenPtr;
+    DefineLineInformation;	/* TIP #280 */
+
+    if (parsePtr->numWords < 3) {
+	PushLiteral(envPtr, "1", 1);
+    } else if (parsePtr->numWords == 3) {
+	tokenPtr = TokenAfter(parsePtr->tokenPtr);
+	CompileWord(envPtr, tokenPtr, interp, 1);
+	tokenPtr = TokenAfter(tokenPtr);
+	CompileWord(envPtr, tokenPtr, interp, 2);
+	TclEmitOpcode(instruction, envPtr);
+    } else if (envPtr->procPtr == NULL) {
+	/*
+	 * No local variable space!
+	 */
+
+	return TCL_ERROR;
+    } else {
+	int tmpIndex = TclFindCompiledLocal(NULL, 0, 1, envPtr);
+	int words;
+
+	tokenPtr = TokenAfter(parsePtr->tokenPtr);
+	CompileWord(envPtr, tokenPtr, interp, 1);
+	tokenPtr = TokenAfter(tokenPtr);
+	CompileWord(envPtr, tokenPtr, interp, 2);
+	if (tmpIndex <= 255) {
+	    TclEmitInstInt1(INST_STORE_SCALAR1, tmpIndex, envPtr);
+	} else {
+	    TclEmitInstInt4(INST_STORE_SCALAR4, tmpIndex, envPtr);
+	}
+	TclEmitOpcode(instruction, envPtr);
+	for (words=3 ; words<parsePtr->numWords ;) {
+	    if (tmpIndex <= 255) {
+		TclEmitInstInt1(INST_LOAD_SCALAR1, tmpIndex, envPtr);
+	    } else {
+		TclEmitInstInt4(INST_LOAD_SCALAR4, tmpIndex, envPtr);
+	    }
+	    tokenPtr = TokenAfter(tokenPtr);
+	    CompileWord(envPtr, tokenPtr, interp, words);
+	    if (++words < parsePtr->numWords) {
+		if (tmpIndex <= 255) {
+		    TclEmitInstInt1(INST_STORE_SCALAR1, tmpIndex, envPtr);
+		} else {
+		    TclEmitInstInt4(INST_STORE_SCALAR4, tmpIndex, envPtr);
+		}
+	    }
+	    TclEmitOpcode(instruction, envPtr);
+	}
+	for (; words>3 ; words--) {
+	    TclEmitOpcode(INST_BITAND, envPtr);
+	}
+
+	/*
+	 * Drop the value from the temp variable; retaining that reference
+	 * might be expensive elsewhere.
+	 */
+
+	PushLiteral(envPtr, "", 0);
+	if (tmpIndex <= 255) {
+	    TclEmitInstInt1(INST_STORE_SCALAR1, tmpIndex, envPtr);
+	} else {
+	    TclEmitInstInt4(INST_STORE_SCALAR4, tmpIndex, envPtr);
+	}
+	TclEmitOpcode(INST_POP, envPtr);
+    }
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclCompile*OpCmd --
+ *
+ *	Procedures called to compile the corresponding "::tcl::mathop::*"
+ *	commands. These are all wrappers around the utility operator command
+ *	compiler functions, except for the compilers for subtraction and
+ *	division, which are special.
+ *
+ * Results:
+ *	Returns TCL_OK for a successful compile. Returns TCL_ERROR to defer
+ *	evaluation to runtime.
+ *
+ * Side effects:
+ *	Instructions are added to envPtr to execute the compiled command at
+ *	runtime.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+TclCompileInvertOpCmd(
+    Tcl_Interp *interp,
+    Tcl_Parse *parsePtr,
+    Command *cmdPtr,		/* Points to defintion of command being
+				 * compiled. */
+    CompileEnv *envPtr)
+{
+    return CompileUnaryOpCmd(interp, parsePtr, INST_BITNOT, envPtr);
+}
+
+int
+TclCompileNotOpCmd(
+    Tcl_Interp *interp,
+    Tcl_Parse *parsePtr,
+    Command *cmdPtr,		/* Points to defintion of command being
+				 * compiled. */
+    CompileEnv *envPtr)
+{
+    return CompileUnaryOpCmd(interp, parsePtr, INST_LNOT, envPtr);
+}
+
+int
+TclCompileAddOpCmd(
+    Tcl_Interp *interp,
+    Tcl_Parse *parsePtr,
+    Command *cmdPtr,		/* Points to defintion of command being
+				 * compiled. */
+    CompileEnv *envPtr)
+{
+    return CompileAssociativeBinaryOpCmd(interp, parsePtr, "0", INST_ADD,
+	    envPtr);
+}
+
+int
+TclCompileMulOpCmd(
+    Tcl_Interp *interp,
+    Tcl_Parse *parsePtr,
+    Command *cmdPtr,		/* Points to defintion of command being
+				 * compiled. */
+    CompileEnv *envPtr)
+{
+    return CompileAssociativeBinaryOpCmd(interp, parsePtr, "1", INST_MULT,
+	    envPtr);
+}
+
+int
+TclCompileAndOpCmd(
+    Tcl_Interp *interp,
+    Tcl_Parse *parsePtr,
+    Command *cmdPtr,		/* Points to defintion of command being
+				 * compiled. */
+    CompileEnv *envPtr)
+{
+    return CompileAssociativeBinaryOpCmd(interp, parsePtr, "-1", INST_BITAND,
+	    envPtr);
+}
+
+int
+TclCompileOrOpCmd(
+    Tcl_Interp *interp,
+    Tcl_Parse *parsePtr,
+    Command *cmdPtr,		/* Points to defintion of command being
+				 * compiled. */
+    CompileEnv *envPtr)
+{
+    return CompileAssociativeBinaryOpCmd(interp, parsePtr, "0", INST_BITOR,
+	    envPtr);
+}
+
+int
+TclCompileXorOpCmd(
+    Tcl_Interp *interp,
+    Tcl_Parse *parsePtr,
+    Command *cmdPtr,		/* Points to defintion of command being
+				 * compiled. */
+    CompileEnv *envPtr)
+{
+    return CompileAssociativeBinaryOpCmd(interp, parsePtr, "0", INST_BITXOR,
+	    envPtr);
+}
+
+int
+TclCompilePowOpCmd(
+    Tcl_Interp *interp,
+    Tcl_Parse *parsePtr,
+    Command *cmdPtr,		/* Points to defintion of command being
+				 * compiled. */
+    CompileEnv *envPtr)
+{
+    /*
+     * This one has its own implementation because the ** operator is the only
+     * one with right associativity.
+     */
+
+    Tcl_Token *tokenPtr = parsePtr->tokenPtr;
+    DefineLineInformation;	/* TIP #280 */
+    int words;
+
+    for (words=1 ; words<parsePtr->numWords ; words++) {
+	tokenPtr = TokenAfter(tokenPtr);
+	CompileWord(envPtr, tokenPtr, interp, words);
+    }
+    if (parsePtr->numWords <= 2) {
+	PushLiteral(envPtr, "1", 1);
+	words++;
+    }
+    while (--words > 1) {
+	TclEmitOpcode(INST_EXPON, envPtr);
+    }
+    return TCL_OK;
+}
+
+int
+TclCompileLshiftOpCmd(
+    Tcl_Interp *interp,
+    Tcl_Parse *parsePtr,
+    Command *cmdPtr,		/* Points to defintion of command being
+				 * compiled. */
+    CompileEnv *envPtr)
+{
+    return CompileStrictlyBinaryOpCmd(interp, parsePtr, INST_LSHIFT, envPtr);
+}
+
+int
+TclCompileRshiftOpCmd(
+    Tcl_Interp *interp,
+    Tcl_Parse *parsePtr,
+    Command *cmdPtr,		/* Points to defintion of command being
+				 * compiled. */
+    CompileEnv *envPtr)
+{
+    return CompileStrictlyBinaryOpCmd(interp, parsePtr, INST_RSHIFT, envPtr);
+}
+
+int
+TclCompileModOpCmd(
+    Tcl_Interp *interp,
+    Tcl_Parse *parsePtr,
+    Command *cmdPtr,		/* Points to defintion of command being
+				 * compiled. */
+    CompileEnv *envPtr)
+{
+    return CompileStrictlyBinaryOpCmd(interp, parsePtr, INST_MOD, envPtr);
+}
+
+int
+TclCompileNeqOpCmd(
+    Tcl_Interp *interp,
+    Tcl_Parse *parsePtr,
+    Command *cmdPtr,		/* Points to defintion of command being
+				 * compiled. */
+    CompileEnv *envPtr)
+{
+    return CompileStrictlyBinaryOpCmd(interp, parsePtr, INST_NEQ, envPtr);
+}
+
+int
+TclCompileStrneqOpCmd(
+    Tcl_Interp *interp,
+    Tcl_Parse *parsePtr,
+    Command *cmdPtr,		/* Points to defintion of command being
+				 * compiled. */
+    CompileEnv *envPtr)
+{
+    return CompileStrictlyBinaryOpCmd(interp, parsePtr, INST_STR_NEQ, envPtr);
+}
+
+int
+TclCompileInOpCmd(
+    Tcl_Interp *interp,
+    Tcl_Parse *parsePtr,
+    Command *cmdPtr,		/* Points to defintion of command being
+				 * compiled. */
+    CompileEnv *envPtr)
+{
+    return CompileStrictlyBinaryOpCmd(interp, parsePtr, INST_LIST_IN, envPtr);
+}
+
+int
+TclCompileNiOpCmd(
+    Tcl_Interp *interp,
+    Tcl_Parse *parsePtr,
+    Command *cmdPtr,		/* Points to defintion of command being
+				 * compiled. */
+    CompileEnv *envPtr)
+{
+    return CompileStrictlyBinaryOpCmd(interp, parsePtr, INST_LIST_NOT_IN,
+	    envPtr);
+}
+
+int
+TclCompileLessOpCmd(
+    Tcl_Interp *interp,
+    Tcl_Parse *parsePtr,
+    Command *cmdPtr,		/* Points to defintion of command being
+				 * compiled. */
+    CompileEnv *envPtr)
+{
+    return CompileComparisonOpCmd(interp, parsePtr, INST_LT, envPtr);
+}
+
+int
+TclCompileLeqOpCmd(
+    Tcl_Interp *interp,
+    Tcl_Parse *parsePtr,
+    Command *cmdPtr,		/* Points to defintion of command being
+				 * compiled. */
+    CompileEnv *envPtr)
+{
+    return CompileComparisonOpCmd(interp, parsePtr, INST_LE, envPtr);
+}
+
+int
+TclCompileGreaterOpCmd(
+    Tcl_Interp *interp,
+    Tcl_Parse *parsePtr,
+    Command *cmdPtr,		/* Points to defintion of command being
+				 * compiled. */
+    CompileEnv *envPtr)
+{
+    return CompileComparisonOpCmd(interp, parsePtr, INST_GT, envPtr);
+}
+
+int
+TclCompileGeqOpCmd(
+    Tcl_Interp *interp,
+    Tcl_Parse *parsePtr,
+    Command *cmdPtr,		/* Points to defintion of command being
+				 * compiled. */
+    CompileEnv *envPtr)
+{
+    return CompileComparisonOpCmd(interp, parsePtr, INST_GE, envPtr);
+}
+
+int
+TclCompileEqOpCmd(
+    Tcl_Interp *interp,
+    Tcl_Parse *parsePtr,
+    Command *cmdPtr,		/* Points to defintion of command being
+				 * compiled. */
+    CompileEnv *envPtr)
+{
+    return CompileComparisonOpCmd(interp, parsePtr, INST_EQ, envPtr);
+}
+
+int
+TclCompileStreqOpCmd(
+    Tcl_Interp *interp,
+    Tcl_Parse *parsePtr,
+    Command *cmdPtr,		/* Points to defintion of command being
+				 * compiled. */
+    CompileEnv *envPtr)
+{
+    return CompileComparisonOpCmd(interp, parsePtr, INST_STR_EQ, envPtr);
+}
+
+int
+TclCompileMinusOpCmd(
+    Tcl_Interp *interp,
+    Tcl_Parse *parsePtr,
+    Command *cmdPtr,		/* Points to defintion of command being
+				 * compiled. */
+    CompileEnv *envPtr)
+{
+    Tcl_Token *tokenPtr = parsePtr->tokenPtr;
+    DefineLineInformation;	/* TIP #280 */
+    int words;
+
+    if (parsePtr->numWords == 1) {
+	/*
+	 * Fallback to direct eval to report syntax error.
+	 */
+
+	return TCL_ERROR;
+    }
+    for (words=1 ; words<parsePtr->numWords ; words++) {
+	tokenPtr = TokenAfter(tokenPtr);
+	CompileWord(envPtr, tokenPtr, interp, words);
+    }
+    if (words == 2) {
+	TclEmitOpcode(INST_UMINUS, envPtr);
+	return TCL_OK;
+    }
+    if (words == 3) {
+	TclEmitOpcode(INST_SUB, envPtr);
+	return TCL_OK;
+    }
+
+    /*
+     * Reverse order of arguments to get precise agreement with [expr] in
+     * calcuations, including roundoff errors.
+     */
+
+    TclEmitInstInt4(INST_REVERSE, words-1, envPtr);
+    while (--words > 1) {
+	TclEmitInstInt4(INST_REVERSE, 2, envPtr);
+	TclEmitOpcode(INST_SUB, envPtr);
+    }
+    return TCL_OK;
+}
+
+int
+TclCompileDivOpCmd(
+    Tcl_Interp *interp,
+    Tcl_Parse *parsePtr,
+    Command *cmdPtr,		/* Points to defintion of command being
+				 * compiled. */
+    CompileEnv *envPtr)
+{
+    Tcl_Token *tokenPtr = parsePtr->tokenPtr;
+    DefineLineInformation;	/* TIP #280 */
+    int words;
+
+    if (parsePtr->numWords == 1) {
+	/*
+	 * Fallback to direct eval to report syntax error.
+	 */
+
+	return TCL_ERROR;
+    }
+    if (parsePtr->numWords == 2) {
+	PushLiteral(envPtr, "1.0", 3);
+    }
+    for (words=1 ; words<parsePtr->numWords ; words++) {
+	tokenPtr = TokenAfter(tokenPtr);
+	CompileWord(envPtr, tokenPtr, interp, words);
+    }
+    if (words <= 3) {
+	TclEmitOpcode(INST_DIV, envPtr);
+	return TCL_OK;
+    }
+
+    /*
+     * Reverse order of arguments to get precise agreement with [expr] in
+     * calcuations, including roundoff errors.
+     */
+
+    TclEmitInstInt4(INST_REVERSE, words-1, envPtr);
+    while (--words > 1) {
+	TclEmitInstInt4(INST_REVERSE, 2, envPtr);
+	TclEmitOpcode(INST_DIV, envPtr);
+    }
+    return TCL_OK;
+}
+
+/*
+ * Local Variables:
+ * mode: c
+ * c-basic-offset: 4
+ * fill-column: 78
+ * End:
+ */