--- /dev/null
+/*
+ * tclAssembly.c --
+ *
+ * Assembler for Tcl bytecodes.
+ *
+ * This file contains the procedures that convert Tcl Assembly Language (TAL)
+ * to a sequence of bytecode instructions for the Tcl execution engine.
+ *
+ * Copyright (c) 2010 by Ozgur Dogan Ugurlu.
+ * Copyright (c) 2010 by Kevin B. Kenny.
+ *
+ * See the file "license.terms" for information on usage and redistribution of
+ * this file, and for a DISCLAIMER OF ALL WARRANTIES.
+ */
+
+/*-
+ *- THINGS TO DO:
+ *- More instructions:
+ *- done - alternate exit point (affects stack and exception range checking)
+ *- break and continue - if exception ranges can be sorted out.
+ *- foreach_start4, foreach_step4
+ *- returnImm, returnStk
+ *- expandStart, expandStkTop, invokeExpanded, expandDrop
+ *- dictFirst, dictNext, dictDone
+ *- dictUpdateStart, dictUpdateEnd
+ *- jumpTable testing
+ *- syntax (?)
+ *- returnCodeBranch
+ *- tclooNext, tclooNextClass
+ */
+
+#include "tclInt.h"
+#include "tclCompile.h"
+#include "tclOOInt.h"
+
+/*
+ * Structure that represents a range of instructions in the bytecode.
+ */
+
+typedef struct CodeRange {
+ int startOffset; /* Start offset in the bytecode array */
+ int endOffset; /* End offset in the bytecode array */
+} CodeRange;
+
+/*
+ * State identified for a basic block's catch context.
+ */
+
+typedef enum BasicBlockCatchState {
+ BBCS_UNKNOWN = 0, /* Catch context has not yet been identified */
+ BBCS_NONE, /* Block is outside of any catch */
+ BBCS_INCATCH, /* Block is within a catch context */
+ BBCS_CAUGHT /* Block is within a catch context and
+ * may be executed after an exception fires */
+} BasicBlockCatchState;
+
+/*
+ * Structure that defines a basic block - a linear sequence of bytecode
+ * instructions with no jumps in or out (including not changing the
+ * state of any exception range).
+ */
+
+typedef struct BasicBlock {
+ int originalStartOffset; /* Instruction offset before JUMP1s were
+ * substituted with JUMP4's */
+ int startOffset; /* Instruction offset of the start of the
+ * block */
+ int startLine; /* Line number in the input script of the
+ * instruction at the start of the block */
+ int jumpOffset; /* Bytecode offset of the 'jump' instruction
+ * that ends the block, or -1 if there is no
+ * jump. */
+ int jumpLine; /* Line number in the input script of the
+ * 'jump' instruction that ends the block, or
+ * -1 if there is no jump */
+ struct BasicBlock* prevPtr; /* Immediate predecessor of this block */
+ struct BasicBlock* predecessor;
+ /* Predecessor of this block in the spanning
+ * tree */
+ struct BasicBlock* successor1;
+ /* BasicBlock structure of the following
+ * block: NULL at the end of the bytecode
+ * sequence. */
+ Tcl_Obj* jumpTarget; /* Jump target label if the jump target is
+ * unresolved */
+ int initialStackDepth; /* Absolute stack depth on entry */
+ int minStackDepth; /* Low-water relative stack depth */
+ int maxStackDepth; /* High-water relative stack depth */
+ int finalStackDepth; /* Relative stack depth on exit */
+ enum BasicBlockCatchState catchState;
+ /* State of the block for 'catch' analysis */
+ int catchDepth; /* Number of nested catches in which the basic
+ * block appears */
+ struct BasicBlock* enclosingCatch;
+ /* BasicBlock structure of the last startCatch
+ * executed on a path to this block, or NULL
+ * if there is no enclosing catch */
+ int foreignExceptionBase; /* Base index of foreign exceptions */
+ int foreignExceptionCount; /* Count of foreign exceptions */
+ ExceptionRange* foreignExceptions;
+ /* ExceptionRange structures for exception
+ * ranges belonging to embedded scripts and
+ * expressions in this block */
+ JumptableInfo* jtPtr; /* Jump table at the end of this basic block */
+ int flags; /* Boolean flags */
+} BasicBlock;
+
+/*
+ * Flags that pertain to a basic block.
+ */
+
+enum BasicBlockFlags {
+ BB_VISITED = (1 << 0), /* Block has been visited in the current
+ * traversal */
+ BB_FALLTHRU = (1 << 1), /* Control may pass from this block to a
+ * successor */
+ BB_JUMP1 = (1 << 2), /* Basic block ends with a 1-byte-offset jump
+ * and may need expansion */
+ BB_JUMPTABLE = (1 << 3), /* Basic block ends with a jump table */
+ BB_BEGINCATCH = (1 << 4), /* Block ends with a 'beginCatch' instruction,
+ * marking it as the start of a 'catch'
+ * sequence. The 'jumpTarget' is the exception
+ * exit from the catch block. */
+ BB_ENDCATCH = (1 << 5) /* Block ends with an 'endCatch' instruction,
+ * unwinding the catch from the exception
+ * stack. */
+};
+
+/*
+ * Source instruction type recognized by the assembler.
+ */
+
+typedef enum TalInstType {
+ ASSEM_1BYTE, /* Fixed arity, 1-byte instruction */
+ ASSEM_BEGIN_CATCH, /* Begin catch: one 4-byte jump offset to be
+ * converted to appropriate exception
+ * ranges */
+ ASSEM_BOOL, /* One Boolean operand */
+ ASSEM_BOOL_LVT4, /* One Boolean, one 4-byte LVT ref. */
+ ASSEM_CLOCK_READ, /* 1-byte unsigned-integer case number, in the
+ * range 0-3 */
+ ASSEM_CONCAT1, /* 1-byte unsigned-integer operand count, must
+ * be strictly positive, consumes N, produces
+ * 1 */
+ ASSEM_DICT_GET, /* 'dict get' and related - consumes N+1
+ * operands, produces 1, N > 0 */
+ ASSEM_DICT_SET, /* specifies key count and LVT index, consumes
+ * N+1 operands, produces 1, N > 0 */
+ ASSEM_DICT_UNSET, /* specifies key count and LVT index, consumes
+ * N operands, produces 1, N > 0 */
+ ASSEM_END_CATCH, /* End catch. No args. Exception range popped
+ * from stack and stack pointer restored. */
+ ASSEM_EVAL, /* 'eval' - evaluate a constant script (by
+ * compiling it in line with the assembly
+ * code! I love Tcl!) */
+ ASSEM_INDEX, /* 4 byte operand, integer or end-integer */
+ ASSEM_INVOKE, /* 1- or 4-byte operand count, must be
+ * strictly positive, consumes N, produces
+ * 1. */
+ ASSEM_JUMP, /* Jump instructions */
+ ASSEM_JUMP4, /* Jump instructions forcing a 4-byte offset */
+ ASSEM_JUMPTABLE, /* Jumptable (switch -exact) */
+ ASSEM_LABEL, /* The assembly directive that defines a
+ * label */
+ ASSEM_LINDEX_MULTI, /* 4-byte operand count, must be strictly
+ * positive, consumes N, produces 1 */
+ ASSEM_LIST, /* 4-byte operand count, must be nonnegative,
+ * consumses N, produces 1 */
+ ASSEM_LSET_FLAT, /* 4-byte operand count, must be >= 3,
+ * consumes N, produces 1 */
+ ASSEM_LVT, /* One operand that references a local
+ * variable */
+ ASSEM_LVT1, /* One 1-byte operand that references a local
+ * variable */
+ ASSEM_LVT1_SINT1, /* One 1-byte operand that references a local
+ * variable, one signed-integer 1-byte
+ * operand */
+ ASSEM_LVT4, /* One 4-byte operand that references a local
+ * variable */
+ ASSEM_OVER, /* OVER: 4-byte operand count, consumes N+1,
+ * produces N+2 */
+ ASSEM_PUSH, /* one literal operand */
+ ASSEM_REGEXP, /* One Boolean operand, but weird mapping to
+ * call flags */
+ ASSEM_REVERSE, /* REVERSE: 4-byte operand count, consumes N,
+ * produces N */
+ ASSEM_SINT1, /* One 1-byte signed-integer operand
+ * (INCR_STK_IMM) */
+ ASSEM_SINT4_LVT4 /* Signed 4-byte integer operand followed by
+ * LVT entry. Fixed arity */
+} TalInstType;
+
+/*
+ * Description of an instruction recognized by the assembler.
+ */
+
+typedef struct TalInstDesc {
+ const char *name; /* Name of instruction. */
+ TalInstType instType; /* The type of instruction */
+ int tclInstCode; /* Instruction code. For instructions having
+ * 1- and 4-byte variables, tclInstCode is
+ * ((1byte)<<8) || (4byte) */
+ int operandsConsumed; /* Number of operands consumed by the
+ * operation, or INT_MIN if the operation is
+ * variadic */
+ int operandsProduced; /* Number of operands produced by the
+ * operation. If negative, the operation has a
+ * net stack effect of -1-operandsProduced */
+} TalInstDesc;
+
+/*
+ * Structure that holds the state of the assembler while generating code.
+ */
+
+typedef struct AssemblyEnv {
+ CompileEnv* envPtr; /* Compilation environment being used for code
+ * generation */
+ Tcl_Parse* parsePtr; /* Parse of the current line of source */
+ Tcl_HashTable labelHash; /* Hash table whose keys are labels and whose
+ * values are 'label' objects storing the code
+ * offsets of the labels. */
+ int cmdLine; /* Current line number within the assembly
+ * code */
+ int* clNext; /* Invisible continuation line for
+ * [info frame] */
+ BasicBlock* head_bb; /* First basic block in the code */
+ BasicBlock* curr_bb; /* Current basic block */
+ int maxDepth; /* Maximum stack depth encountered */
+ int curCatchDepth; /* Current depth of catches */
+ int maxCatchDepth; /* Maximum depth of catches encountered */
+ int flags; /* Compilation flags (TCL_EVAL_DIRECT) */
+} AssemblyEnv;
+
+/*
+ * Static functions defined in this file.
+ */
+
+static void AddBasicBlockRangeToErrorInfo(AssemblyEnv*,
+ BasicBlock*);
+static BasicBlock * AllocBB(AssemblyEnv*);
+static int AssembleOneLine(AssemblyEnv* envPtr);
+static void BBAdjustStackDepth(BasicBlock* bbPtr, int consumed,
+ int produced);
+static void BBUpdateStackReqs(BasicBlock* bbPtr, int tblIdx,
+ int count);
+static void BBEmitInstInt1(AssemblyEnv* assemEnvPtr, int tblIdx,
+ int opnd, int count);
+static void BBEmitInstInt4(AssemblyEnv* assemEnvPtr, int tblIdx,
+ int opnd, int count);
+static void BBEmitInst1or4(AssemblyEnv* assemEnvPtr, int tblIdx,
+ int param, int count);
+static void BBEmitOpcode(AssemblyEnv* assemEnvPtr, int tblIdx,
+ int count);
+static int BuildExceptionRanges(AssemblyEnv* assemEnvPtr);
+static int CalculateJumpRelocations(AssemblyEnv*, int*);
+static int CheckForUnclosedCatches(AssemblyEnv*);
+static int CheckForThrowInWrongContext(AssemblyEnv*);
+static int CheckNonThrowingBlock(AssemblyEnv*, BasicBlock*);
+static int BytecodeMightThrow(unsigned char);
+static int CheckJumpTableLabels(AssemblyEnv*, BasicBlock*);
+static int CheckNamespaceQualifiers(Tcl_Interp*, const char*,
+ int);
+static int CheckNonNegative(Tcl_Interp*, int);
+static int CheckOneByte(Tcl_Interp*, int);
+static int CheckSignedOneByte(Tcl_Interp*, int);
+static int CheckStack(AssemblyEnv*);
+static int CheckStrictlyPositive(Tcl_Interp*, int);
+static ByteCode * CompileAssembleObj(Tcl_Interp *interp,
+ Tcl_Obj *objPtr);
+static void CompileEmbeddedScript(AssemblyEnv*, Tcl_Token*,
+ const TalInstDesc*);
+static int DefineLabel(AssemblyEnv* envPtr, const char* label);
+static void DeleteMirrorJumpTable(JumptableInfo* jtPtr);
+static void DupAssembleCodeInternalRep(Tcl_Obj* src,
+ Tcl_Obj* dest);
+static void FillInJumpOffsets(AssemblyEnv*);
+static int CreateMirrorJumpTable(AssemblyEnv* assemEnvPtr,
+ Tcl_Obj* jumpTable);
+static int FindLocalVar(AssemblyEnv* envPtr,
+ Tcl_Token** tokenPtrPtr);
+static int FinishAssembly(AssemblyEnv*);
+static void FreeAssembleCodeInternalRep(Tcl_Obj *objPtr);
+static void FreeAssemblyEnv(AssemblyEnv*);
+static int GetBooleanOperand(AssemblyEnv*, Tcl_Token**, int*);
+static int GetListIndexOperand(AssemblyEnv*, Tcl_Token**, int*);
+static int GetIntegerOperand(AssemblyEnv*, Tcl_Token**, int*);
+static int GetNextOperand(AssemblyEnv*, Tcl_Token**, Tcl_Obj**);
+static void LookForFreshCatches(BasicBlock*, BasicBlock**);
+static void MoveCodeForJumps(AssemblyEnv*, int);
+static void MoveExceptionRangesToBasicBlock(AssemblyEnv*, int);
+static AssemblyEnv* NewAssemblyEnv(CompileEnv*, int);
+static int ProcessCatches(AssemblyEnv*);
+static int ProcessCatchesInBasicBlock(AssemblyEnv*, BasicBlock*,
+ BasicBlock*, enum BasicBlockCatchState, int);
+static void ResetVisitedBasicBlocks(AssemblyEnv*);
+static void ResolveJumpTableTargets(AssemblyEnv*, BasicBlock*);
+static void ReportUndefinedLabel(AssemblyEnv*, BasicBlock*,
+ Tcl_Obj*);
+static void RestoreEmbeddedExceptionRanges(AssemblyEnv*);
+static int StackCheckBasicBlock(AssemblyEnv*, BasicBlock *,
+ BasicBlock *, int);
+static BasicBlock* StartBasicBlock(AssemblyEnv*, int fallthrough,
+ Tcl_Obj* jumpLabel);
+/* static int AdvanceIp(const unsigned char *pc); */
+static int StackCheckBasicBlock(AssemblyEnv*, BasicBlock *,
+ BasicBlock *, int);
+static int StackCheckExit(AssemblyEnv*);
+static void StackFreshCatches(AssemblyEnv*, BasicBlock*, int,
+ BasicBlock**, int*);
+static void SyncStackDepth(AssemblyEnv*);
+static int TclAssembleCode(CompileEnv* envPtr, const char* code,
+ int codeLen, int flags);
+static void UnstackExpiredCatches(CompileEnv*, BasicBlock*, int,
+ BasicBlock**, int*);
+
+/*
+ * Tcl_ObjType that describes bytecode emitted by the assembler.
+ */
+
+static const Tcl_ObjType assembleCodeType = {
+ "assemblecode",
+ FreeAssembleCodeInternalRep, /* freeIntRepProc */
+ DupAssembleCodeInternalRep, /* dupIntRepProc */
+ NULL, /* updateStringProc */
+ NULL /* setFromAnyProc */
+};
+
+/*
+ * Source instructions recognized in the Tcl Assembly Language (TAL)
+ */
+
+static const TalInstDesc TalInstructionTable[] = {
+ /* PUSH must be first, see the code near the end of TclAssembleCode */
+ {"push", ASSEM_PUSH, (INST_PUSH1<<8
+ | INST_PUSH4), 0, 1},
+
+ {"add", ASSEM_1BYTE, INST_ADD, 2, 1},
+ {"append", ASSEM_LVT, (INST_APPEND_SCALAR1<<8
+ | INST_APPEND_SCALAR4),1, 1},
+ {"appendArray", ASSEM_LVT, (INST_APPEND_ARRAY1<<8
+ | INST_APPEND_ARRAY4), 2, 1},
+ {"appendArrayStk", ASSEM_1BYTE, INST_APPEND_ARRAY_STK, 3, 1},
+ {"appendStk", ASSEM_1BYTE, INST_APPEND_STK, 2, 1},
+ {"arrayExistsImm", ASSEM_LVT4, INST_ARRAY_EXISTS_IMM, 0, 1},
+ {"arrayExistsStk", ASSEM_1BYTE, INST_ARRAY_EXISTS_STK, 1, 1},
+ {"arrayMakeImm", ASSEM_LVT4, INST_ARRAY_MAKE_IMM, 0, 0},
+ {"arrayMakeStk", ASSEM_1BYTE, INST_ARRAY_MAKE_STK, 1, 0},
+ {"beginCatch", ASSEM_BEGIN_CATCH,
+ INST_BEGIN_CATCH4, 0, 0},
+ {"bitand", ASSEM_1BYTE, INST_BITAND, 2, 1},
+ {"bitnot", ASSEM_1BYTE, INST_BITNOT, 1, 1},
+ {"bitor", ASSEM_1BYTE, INST_BITOR, 2, 1},
+ {"bitxor", ASSEM_1BYTE, INST_BITXOR, 2, 1},
+ {"clockRead", ASSEM_CLOCK_READ, INST_CLOCK_READ, 0, 1},
+ {"concat", ASSEM_CONCAT1, INST_STR_CONCAT1, INT_MIN,1},
+ {"concatStk", ASSEM_LIST, INST_CONCAT_STK, INT_MIN,1},
+ {"coroName", ASSEM_1BYTE, INST_COROUTINE_NAME, 0, 1},
+ {"currentNamespace",ASSEM_1BYTE, INST_NS_CURRENT, 0, 1},
+ {"dictAppend", ASSEM_LVT4, INST_DICT_APPEND, 2, 1},
+ {"dictExists", ASSEM_DICT_GET, INST_DICT_EXISTS, INT_MIN,1},
+ {"dictExpand", ASSEM_1BYTE, INST_DICT_EXPAND, 3, 1},
+ {"dictGet", ASSEM_DICT_GET, INST_DICT_GET, INT_MIN,1},
+ {"dictIncrImm", ASSEM_SINT4_LVT4,
+ INST_DICT_INCR_IMM, 1, 1},
+ {"dictLappend", ASSEM_LVT4, INST_DICT_LAPPEND, 2, 1},
+ {"dictRecombineStk",ASSEM_1BYTE, INST_DICT_RECOMBINE_STK,3, 0},
+ {"dictRecombineImm",ASSEM_LVT4, INST_DICT_RECOMBINE_IMM,2, 0},
+ {"dictSet", ASSEM_DICT_SET, INST_DICT_SET, INT_MIN,1},
+ {"dictUnset", ASSEM_DICT_UNSET,
+ INST_DICT_UNSET, INT_MIN,1},
+ {"div", ASSEM_1BYTE, INST_DIV, 2, 1},
+ {"dup", ASSEM_1BYTE, INST_DUP, 1, 2},
+ {"endCatch", ASSEM_END_CATCH,INST_END_CATCH, 0, 0},
+ {"eq", ASSEM_1BYTE, INST_EQ, 2, 1},
+ {"eval", ASSEM_EVAL, INST_EVAL_STK, 1, 1},
+ {"evalStk", ASSEM_1BYTE, INST_EVAL_STK, 1, 1},
+ {"exist", ASSEM_LVT4, INST_EXIST_SCALAR, 0, 1},
+ {"existArray", ASSEM_LVT4, INST_EXIST_ARRAY, 1, 1},
+ {"existArrayStk", ASSEM_1BYTE, INST_EXIST_ARRAY_STK, 2, 1},
+ {"existStk", ASSEM_1BYTE, INST_EXIST_STK, 1, 1},
+ {"expon", ASSEM_1BYTE, INST_EXPON, 2, 1},
+ {"expr", ASSEM_EVAL, INST_EXPR_STK, 1, 1},
+ {"exprStk", ASSEM_1BYTE, INST_EXPR_STK, 1, 1},
+ {"ge", ASSEM_1BYTE, INST_GE, 2, 1},
+ {"gt", ASSEM_1BYTE, INST_GT, 2, 1},
+ {"incr", ASSEM_LVT1, INST_INCR_SCALAR1, 1, 1},
+ {"incrArray", ASSEM_LVT1, INST_INCR_ARRAY1, 2, 1},
+ {"incrArrayImm", ASSEM_LVT1_SINT1,
+ INST_INCR_ARRAY1_IMM, 1, 1},
+ {"incrArrayStk", ASSEM_1BYTE, INST_INCR_ARRAY_STK, 3, 1},
+ {"incrArrayStkImm", ASSEM_SINT1, INST_INCR_ARRAY_STK_IMM,2, 1},
+ {"incrImm", ASSEM_LVT1_SINT1,
+ INST_INCR_SCALAR1_IMM, 0, 1},
+ {"incrStk", ASSEM_1BYTE, INST_INCR_STK, 2, 1},
+ {"incrStkImm", ASSEM_SINT1, INST_INCR_STK_IMM, 1, 1},
+ {"infoLevelArgs", ASSEM_1BYTE, INST_INFO_LEVEL_ARGS, 1, 1},
+ {"infoLevelNumber", ASSEM_1BYTE, INST_INFO_LEVEL_NUM, 0, 1},
+ {"invokeStk", ASSEM_INVOKE, (INST_INVOKE_STK1 << 8
+ | INST_INVOKE_STK4), INT_MIN,1},
+ {"jump", ASSEM_JUMP, INST_JUMP1, 0, 0},
+ {"jump4", ASSEM_JUMP4, INST_JUMP4, 0, 0},
+ {"jumpFalse", ASSEM_JUMP, INST_JUMP_FALSE1, 1, 0},
+ {"jumpFalse4", ASSEM_JUMP4, INST_JUMP_FALSE4, 1, 0},
+ {"jumpTable", ASSEM_JUMPTABLE,INST_JUMP_TABLE, 1, 0},
+ {"jumpTrue", ASSEM_JUMP, INST_JUMP_TRUE1, 1, 0},
+ {"jumpTrue4", ASSEM_JUMP4, INST_JUMP_TRUE4, 1, 0},
+ {"label", ASSEM_LABEL, 0, 0, 0},
+ {"land", ASSEM_1BYTE, INST_LAND, 2, 1},
+ {"lappend", ASSEM_LVT, (INST_LAPPEND_SCALAR1<<8
+ | INST_LAPPEND_SCALAR4),
+ 1, 1},
+ {"lappendArray", ASSEM_LVT, (INST_LAPPEND_ARRAY1<<8
+ | INST_LAPPEND_ARRAY4),2, 1},
+ {"lappendArrayStk", ASSEM_1BYTE, INST_LAPPEND_ARRAY_STK, 3, 1},
+ {"lappendList", ASSEM_LVT4, INST_LAPPEND_LIST, 1, 1},
+ {"lappendListArray",ASSEM_LVT4, INST_LAPPEND_LIST_ARRAY,2, 1},
+ {"lappendListArrayStk", ASSEM_1BYTE,INST_LAPPEND_LIST_ARRAY_STK, 3, 1},
+ {"lappendListStk", ASSEM_1BYTE, INST_LAPPEND_LIST_STK, 2, 1},
+ {"lappendStk", ASSEM_1BYTE, INST_LAPPEND_STK, 2, 1},
+ {"le", ASSEM_1BYTE, INST_LE, 2, 1},
+ {"lindexMulti", ASSEM_LINDEX_MULTI,
+ INST_LIST_INDEX_MULTI, INT_MIN,1},
+ {"list", ASSEM_LIST, INST_LIST, INT_MIN,1},
+ {"listConcat", ASSEM_1BYTE, INST_LIST_CONCAT, 2, 1},
+ {"listIn", ASSEM_1BYTE, INST_LIST_IN, 2, 1},
+ {"listIndex", ASSEM_1BYTE, INST_LIST_INDEX, 2, 1},
+ {"listIndexImm", ASSEM_INDEX, INST_LIST_INDEX_IMM, 1, 1},
+ {"listLength", ASSEM_1BYTE, INST_LIST_LENGTH, 1, 1},
+ {"listNotIn", ASSEM_1BYTE, INST_LIST_NOT_IN, 2, 1},
+ {"load", ASSEM_LVT, (INST_LOAD_SCALAR1 << 8
+ | INST_LOAD_SCALAR4), 0, 1},
+ {"loadArray", ASSEM_LVT, (INST_LOAD_ARRAY1<<8
+ | INST_LOAD_ARRAY4), 1, 1},
+ {"loadArrayStk", ASSEM_1BYTE, INST_LOAD_ARRAY_STK, 2, 1},
+ {"loadStk", ASSEM_1BYTE, INST_LOAD_STK, 1, 1},
+ {"lor", ASSEM_1BYTE, INST_LOR, 2, 1},
+ {"lsetFlat", ASSEM_LSET_FLAT,INST_LSET_FLAT, INT_MIN,1},
+ {"lsetList", ASSEM_1BYTE, INST_LSET_LIST, 3, 1},
+ {"lshift", ASSEM_1BYTE, INST_LSHIFT, 2, 1},
+ {"lt", ASSEM_1BYTE, INST_LT, 2, 1},
+ {"mod", ASSEM_1BYTE, INST_MOD, 2, 1},
+ {"mult", ASSEM_1BYTE, INST_MULT, 2, 1},
+ {"neq", ASSEM_1BYTE, INST_NEQ, 2, 1},
+ {"nop", ASSEM_1BYTE, INST_NOP, 0, 0},
+ {"not", ASSEM_1BYTE, INST_LNOT, 1, 1},
+ {"nsupvar", ASSEM_LVT4, INST_NSUPVAR, 2, 1},
+ {"numericType", ASSEM_1BYTE, INST_NUM_TYPE, 1, 1},
+ {"originCmd", ASSEM_1BYTE, INST_ORIGIN_COMMAND, 1, 1},
+ {"over", ASSEM_OVER, INST_OVER, INT_MIN,-1-1},
+ {"pop", ASSEM_1BYTE, INST_POP, 1, 0},
+ {"pushReturnCode", ASSEM_1BYTE, INST_PUSH_RETURN_CODE, 0, 1},
+ {"pushReturnOpts", ASSEM_1BYTE, INST_PUSH_RETURN_OPTIONS,
+ 0, 1},
+ {"pushResult", ASSEM_1BYTE, INST_PUSH_RESULT, 0, 1},
+ {"regexp", ASSEM_REGEXP, INST_REGEXP, 2, 1},
+ {"resolveCmd", ASSEM_1BYTE, INST_RESOLVE_COMMAND, 1, 1},
+ {"reverse", ASSEM_REVERSE, INST_REVERSE, INT_MIN,-1-0},
+ {"rshift", ASSEM_1BYTE, INST_RSHIFT, 2, 1},
+ {"store", ASSEM_LVT, (INST_STORE_SCALAR1<<8
+ | INST_STORE_SCALAR4), 1, 1},
+ {"storeArray", ASSEM_LVT, (INST_STORE_ARRAY1<<8
+ | INST_STORE_ARRAY4), 2, 1},
+ {"storeArrayStk", ASSEM_1BYTE, INST_STORE_ARRAY_STK, 3, 1},
+ {"storeStk", ASSEM_1BYTE, INST_STORE_STK, 2, 1},
+ {"strcaseLower", ASSEM_1BYTE, INST_STR_LOWER, 1, 1},
+ {"strcaseTitle", ASSEM_1BYTE, INST_STR_TITLE, 1, 1},
+ {"strcaseUpper", ASSEM_1BYTE, INST_STR_UPPER, 1, 1},
+ {"strcmp", ASSEM_1BYTE, INST_STR_CMP, 2, 1},
+ {"strcat", ASSEM_CONCAT1, INST_STR_CONCAT1, INT_MIN,1},
+ {"streq", ASSEM_1BYTE, INST_STR_EQ, 2, 1},
+ {"strfind", ASSEM_1BYTE, INST_STR_FIND, 2, 1},
+ {"strindex", ASSEM_1BYTE, INST_STR_INDEX, 2, 1},
+ {"strlen", ASSEM_1BYTE, INST_STR_LEN, 1, 1},
+ {"strmap", ASSEM_1BYTE, INST_STR_MAP, 3, 1},
+ {"strmatch", ASSEM_BOOL, INST_STR_MATCH, 2, 1},
+ {"strneq", ASSEM_1BYTE, INST_STR_NEQ, 2, 1},
+ {"strrange", ASSEM_1BYTE, INST_STR_RANGE, 3, 1},
+ {"strreplace", ASSEM_1BYTE, INST_STR_REPLACE, 4, 1},
+ {"strrfind", ASSEM_1BYTE, INST_STR_FIND_LAST, 2, 1},
+ {"strtrim", ASSEM_1BYTE, INST_STR_TRIM, 2, 1},
+ {"strtrimLeft", ASSEM_1BYTE, INST_STR_TRIM_LEFT, 2, 1},
+ {"strtrimRight", ASSEM_1BYTE, INST_STR_TRIM_RIGHT, 2, 1},
+ {"sub", ASSEM_1BYTE, INST_SUB, 2, 1},
+ {"tclooClass", ASSEM_1BYTE, INST_TCLOO_CLASS, 1, 1},
+ {"tclooIsObject", ASSEM_1BYTE, INST_TCLOO_IS_OBJECT, 1, 1},
+ {"tclooNamespace", ASSEM_1BYTE, INST_TCLOO_NS, 1, 1},
+ {"tclooSelf", ASSEM_1BYTE, INST_TCLOO_SELF, 0, 1},
+ {"tryCvtToBoolean", ASSEM_1BYTE, INST_TRY_CVT_TO_BOOLEAN,1, 2},
+ {"tryCvtToNumeric", ASSEM_1BYTE, INST_TRY_CVT_TO_NUMERIC,1, 1},
+ {"uminus", ASSEM_1BYTE, INST_UMINUS, 1, 1},
+ {"unset", ASSEM_BOOL_LVT4,INST_UNSET_SCALAR, 0, 0},
+ {"unsetArray", ASSEM_BOOL_LVT4,INST_UNSET_ARRAY, 1, 0},
+ {"unsetArrayStk", ASSEM_BOOL, INST_UNSET_ARRAY_STK, 2, 0},
+ {"unsetStk", ASSEM_BOOL, INST_UNSET_STK, 1, 0},
+ {"uplus", ASSEM_1BYTE, INST_UPLUS, 1, 1},
+ {"upvar", ASSEM_LVT4, INST_UPVAR, 2, 1},
+ {"variable", ASSEM_LVT4, INST_VARIABLE, 1, 0},
+ {"verifyDict", ASSEM_1BYTE, INST_DICT_VERIFY, 1, 0},
+ {"yield", ASSEM_1BYTE, INST_YIELD, 1, 1},
+ {NULL, ASSEM_1BYTE, 0, 0, 0}
+};
+
+/*
+ * List of instructions that cannot throw an exception under any
+ * circumstances. These instructions are the ones that are permissible after
+ * an exception is caught but before the corresponding exception range is
+ * popped from the stack.
+ * The instructions must be in ascending order by numeric operation code.
+ */
+
+static const unsigned char NonThrowingByteCodes[] = {
+ INST_PUSH1, INST_PUSH4, INST_POP, INST_DUP, /* 1-4 */
+ INST_JUMP1, INST_JUMP4, /* 34-35 */
+ INST_END_CATCH, INST_PUSH_RESULT, INST_PUSH_RETURN_CODE, /* 70-72 */
+ INST_STR_EQ, INST_STR_NEQ, INST_STR_CMP, INST_STR_LEN, /* 73-76 */
+ INST_LIST, /* 79 */
+ INST_OVER, /* 95 */
+ INST_PUSH_RETURN_OPTIONS, /* 108 */
+ INST_REVERSE, /* 126 */
+ INST_NOP, /* 132 */
+ INST_STR_MAP, /* 143 */
+ INST_STR_FIND, /* 144 */
+ INST_COROUTINE_NAME, /* 149 */
+ INST_NS_CURRENT, /* 151 */
+ INST_INFO_LEVEL_NUM, /* 152 */
+ INST_RESOLVE_COMMAND, /* 154 */
+ INST_STR_TRIM, INST_STR_TRIM_LEFT, INST_STR_TRIM_RIGHT, /* 166-168 */
+ INST_CONCAT_STK, /* 169 */
+ INST_STR_UPPER, INST_STR_LOWER, INST_STR_TITLE, /* 170-172 */
+ INST_NUM_TYPE /* 180 */
+};
+
+/*
+ * Helper macros.
+ */
+
+#if defined(TCL_DEBUG_ASSEMBLY) && defined(__GNUC__) && __GNUC__ > 2
+#define DEBUG_PRINT(...) fprintf(stderr, ##__VA_ARGS__);fflush(stderr)
+#elif defined(__GNUC__) && __GNUC__ > 2
+#define DEBUG_PRINT(...) /* nothing */
+#else
+#define DEBUG_PRINT /* nothing */
+#endif
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * BBAdjustStackDepth --
+ *
+ * When an opcode is emitted, adjusts the stack information in the basic
+ * block to reflect the number of operands produced and consumed.
+ *
+ * Results:
+ * None.
+ *
+ * Side effects:
+ * Updates minimum, maximum and final stack requirements in the basic
+ * block.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static void
+BBAdjustStackDepth(
+ BasicBlock *bbPtr, /* Structure describing the basic block */
+ int consumed, /* Count of operands consumed by the
+ * operation */
+ int produced) /* Count of operands produced by the
+ * operation */
+{
+ int depth = bbPtr->finalStackDepth;
+
+ depth -= consumed;
+ if (depth < bbPtr->minStackDepth) {
+ bbPtr->minStackDepth = depth;
+ }
+ depth += produced;
+ if (depth > bbPtr->maxStackDepth) {
+ bbPtr->maxStackDepth = depth;
+ }
+ bbPtr->finalStackDepth = depth;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * BBUpdateStackReqs --
+ *
+ * Updates the stack requirements of a basic block, given the opcode
+ * being emitted and an operand count.
+ *
+ * Results:
+ * None.
+ *
+ * Side effects:
+ * Updates min, max and final stack requirements in the basic block.
+ *
+ * Notes:
+ * This function must not be called for instructions such as REVERSE and
+ * OVER that are variadic but do not consume all their operands. Instead,
+ * BBAdjustStackDepth should be called directly.
+ *
+ * count should be provided only for variadic operations. For operations
+ * with known arity, count should be 0.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static void
+BBUpdateStackReqs(
+ BasicBlock* bbPtr, /* Structure describing the basic block */
+ int tblIdx, /* Index in TalInstructionTable of the
+ * operation being assembled */
+ int count) /* Count of operands for variadic insts */
+{
+ int consumed = TalInstructionTable[tblIdx].operandsConsumed;
+ int produced = TalInstructionTable[tblIdx].operandsProduced;
+
+ if (consumed == INT_MIN) {
+ /*
+ * The instruction is variadic; it consumes 'count' operands.
+ */
+
+ consumed = count;
+ }
+ if (produced < 0) {
+ /*
+ * The instruction leaves some of its variadic operands on the stack,
+ * with net stack effect of '-1-produced'
+ */
+
+ produced = consumed - produced - 1;
+ }
+ BBAdjustStackDepth(bbPtr, consumed, produced);
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * BBEmitOpcode, BBEmitInstInt1, BBEmitInstInt4 --
+ *
+ * Emit the opcode part of an instruction, or the entirety of an
+ * instruction with a 1- or 4-byte operand, and adjust stack
+ * requirements.
+ *
+ * Results:
+ * None.
+ *
+ * Side effects:
+ * Stores instruction and operand in the operand stream, and adjusts the
+ * stack.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static void
+BBEmitOpcode(
+ AssemblyEnv* assemEnvPtr, /* Assembly environment */
+ int tblIdx, /* Table index in TalInstructionTable of op */
+ int count) /* Operand count for variadic ops */
+{
+ CompileEnv* envPtr = assemEnvPtr->envPtr;
+ /* Compilation environment */
+ BasicBlock* bbPtr = assemEnvPtr->curr_bb;
+ /* Current basic block */
+ int op = TalInstructionTable[tblIdx].tclInstCode & 0xFF;
+
+ /*
+ * If this is the first instruction in a basic block, record its line
+ * number.
+ */
+
+ if (bbPtr->startOffset == envPtr->codeNext - envPtr->codeStart) {
+ bbPtr->startLine = assemEnvPtr->cmdLine;
+ }
+
+ TclEmitInt1(op, envPtr);
+ TclUpdateAtCmdStart(op, envPtr);
+ BBUpdateStackReqs(bbPtr, tblIdx, count);
+}
+
+static void
+BBEmitInstInt1(
+ AssemblyEnv* assemEnvPtr, /* Assembly environment */
+ int tblIdx, /* Index in TalInstructionTable of op */
+ int opnd, /* 1-byte operand */
+ int count) /* Operand count for variadic ops */
+{
+ BBEmitOpcode(assemEnvPtr, tblIdx, count);
+ TclEmitInt1(opnd, assemEnvPtr->envPtr);
+}
+
+static void
+BBEmitInstInt4(
+ AssemblyEnv* assemEnvPtr, /* Assembly environment */
+ int tblIdx, /* Index in TalInstructionTable of op */
+ int opnd, /* 4-byte operand */
+ int count) /* Operand count for variadic ops */
+{
+ BBEmitOpcode(assemEnvPtr, tblIdx, count);
+ TclEmitInt4(opnd, assemEnvPtr->envPtr);
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * BBEmitInst1or4 --
+ *
+ * Emits a 1- or 4-byte operation according to the magnitude of the
+ * operand.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static void
+BBEmitInst1or4(
+ AssemblyEnv* assemEnvPtr, /* Assembly environment */
+ int tblIdx, /* Index in TalInstructionTable of op */
+ int param, /* Variable-length parameter */
+ int count) /* Arity if variadic */
+{
+ CompileEnv* envPtr = assemEnvPtr->envPtr;
+ /* Compilation environment */
+ BasicBlock* bbPtr = assemEnvPtr->curr_bb;
+ /* Current basic block */
+ int op = TalInstructionTable[tblIdx].tclInstCode;
+
+ if (param <= 0xFF) {
+ op >>= 8;
+ } else {
+ op &= 0xFF;
+ }
+ TclEmitInt1(op, envPtr);
+ if (param <= 0xFF) {
+ TclEmitInt1(param, envPtr);
+ } else {
+ TclEmitInt4(param, envPtr);
+ }
+ TclUpdateAtCmdStart(op, envPtr);
+ BBUpdateStackReqs(bbPtr, tblIdx, count);
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * Tcl_AssembleObjCmd, TclNRAssembleObjCmd --
+ *
+ * Direct evaluation path for tcl::unsupported::assemble
+ *
+ * Results:
+ * Returns a standard Tcl result.
+ *
+ * Side effects:
+ * Assembles the code in objv[1], and executes it, so side effects
+ * include whatever the code does.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+int
+Tcl_AssembleObjCmd(
+ ClientData dummy, /* Not used. */
+ Tcl_Interp *interp, /* Current interpreter. */
+ int objc, /* Number of arguments. */
+ Tcl_Obj *const objv[]) /* Argument objects. */
+{
+ /*
+ * Boilerplate - make sure that there is an NRE trampoline on the C stack
+ * because there needs to be one in place to execute bytecode.
+ */
+
+ return Tcl_NRCallObjProc(interp, TclNRAssembleObjCmd, dummy, objc, objv);
+}
+
+int
+TclNRAssembleObjCmd(
+ ClientData dummy, /* Not used. */
+ Tcl_Interp *interp, /* Current interpreter. */
+ int objc, /* Number of arguments. */
+ Tcl_Obj *const objv[]) /* Argument objects. */
+{
+ ByteCode *codePtr; /* Pointer to the bytecode to execute */
+ Tcl_Obj* backtrace; /* Object where extra error information is
+ * constructed. */
+
+ (void)dummy;
+ if (objc != 2) {
+ Tcl_WrongNumArgs(interp, 1, objv, "bytecodeList");
+ return TCL_ERROR;
+ }
+
+ /*
+ * Assemble the source to bytecode.
+ */
+
+ codePtr = CompileAssembleObj(interp, objv[1]);
+
+ /*
+ * On failure, report error line.
+ */
+
+ if (codePtr == NULL) {
+ Tcl_AddErrorInfo(interp, "\n (\"");
+ Tcl_AppendObjToErrorInfo(interp, objv[0]);
+ Tcl_AddErrorInfo(interp, "\" body, line ");
+ TclNewIntObj(backtrace, Tcl_GetErrorLine(interp));
+ Tcl_AppendObjToErrorInfo(interp, backtrace);
+ Tcl_AddErrorInfo(interp, ")");
+ return TCL_ERROR;
+ }
+
+ /*
+ * Use NRE to evaluate the bytecode from the trampoline.
+ */
+
+ return TclNRExecuteByteCode(interp, codePtr);
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * CompileAssembleObj --
+ *
+ * Sets up and assembles Tcl bytecode for the direct-execution path in
+ * the Tcl bytecode assembler.
+ *
+ * Results:
+ * Returns a pointer to the assembled code. Returns NULL if the assembly
+ * fails for any reason, with an appropriate error message in the
+ * interpreter.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static ByteCode *
+CompileAssembleObj(
+ Tcl_Interp *interp, /* Tcl interpreter */
+ Tcl_Obj *objPtr) /* Source code to assemble */
+{
+ Interp *iPtr = (Interp *) interp;
+ /* Internals of the interpreter */
+ CompileEnv compEnv; /* Compilation environment structure */
+ ByteCode *codePtr = NULL;
+ /* Bytecode resulting from the assembly */
+ Namespace* namespacePtr; /* Namespace in which variable and command
+ * names in the bytecode resolve */
+ int status; /* Status return from Tcl_AssembleCode */
+ const char* source; /* String representation of the source code */
+ int sourceLen; /* Length of the source code in bytes */
+
+ /*
+ * Get the expression ByteCode from the object. If it exists, make sure it
+ * is valid in the current context.
+ */
+
+ if (objPtr->typePtr == &assembleCodeType) {
+ namespacePtr = iPtr->varFramePtr->nsPtr;
+ codePtr = (ByteCode *)objPtr->internalRep.twoPtrValue.ptr1;
+ if (((Interp *) *codePtr->interpHandle == iPtr)
+ && (codePtr->compileEpoch == iPtr->compileEpoch)
+ && (codePtr->nsPtr == namespacePtr)
+ && (codePtr->nsEpoch == namespacePtr->resolverEpoch)
+ && (codePtr->localCachePtr
+ == iPtr->varFramePtr->localCachePtr)) {
+ return codePtr;
+ }
+
+ /*
+ * Not valid, so free it and regenerate.
+ */
+
+ FreeAssembleCodeInternalRep(objPtr);
+ }
+
+ /*
+ * Set up the compilation environment, and assemble the code.
+ */
+
+ source = TclGetStringFromObj(objPtr, &sourceLen);
+ TclInitCompileEnv(interp, &compEnv, source, sourceLen, NULL, 0);
+ status = TclAssembleCode(&compEnv, source, sourceLen, TCL_EVAL_DIRECT);
+ if (status != TCL_OK) {
+ /*
+ * Assembly failed. Clean up and report the error.
+ */
+ TclFreeCompileEnv(&compEnv);
+ return NULL;
+ }
+
+ /*
+ * Add a "done" instruction as the last instruction and change the object
+ * into a ByteCode object. Ownership of the literal objects and aux data
+ * items is given to the ByteCode object.
+ */
+
+ TclEmitOpcode(INST_DONE, &compEnv);
+ TclInitByteCodeObj(objPtr, &compEnv);
+ objPtr->typePtr = &assembleCodeType;
+ TclFreeCompileEnv(&compEnv);
+
+ /*
+ * Record the local variable context to which the bytecode pertains
+ */
+
+ codePtr = (ByteCode *)objPtr->internalRep.twoPtrValue.ptr1;
+ if (iPtr->varFramePtr->localCachePtr) {
+ codePtr->localCachePtr = iPtr->varFramePtr->localCachePtr;
+ codePtr->localCachePtr->refCount++;
+ }
+
+ /*
+ * Report on what the assembler did.
+ */
+
+#ifdef TCL_COMPILE_DEBUG
+ if (tclTraceCompile >= 2) {
+ TclPrintByteCodeObj(interp, objPtr);
+ fflush(stdout);
+ }
+#endif /* TCL_COMPILE_DEBUG */
+
+ return codePtr;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * TclCompileAssembleCmd --
+ *
+ * Compilation procedure for the '::tcl::unsupported::assemble' command.
+ *
+ * Results:
+ * Returns a standard Tcl result.
+ *
+ * Side effects:
+ * Puts the result of assembling the code into the bytecode stream in
+ * 'compileEnv'.
+ *
+ * This procedure makes sure that the command has a single arg, which is
+ * constant. If that condition is met, the procedure calls TclAssembleCode to
+ * produce bytecode for the given assembly code, and returns any error
+ * resulting from the assembly.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+int
+TclCompileAssembleCmd(
+ 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; /* Token in the input script */
+
+ int numCommands = envPtr->numCommands;
+ int offset = envPtr->codeNext - envPtr->codeStart;
+ int depth = envPtr->currStackDepth;
+ (void)cmdPtr;
+ /*
+ * Make sure that the command has a single arg that is a simple word.
+ */
+
+ if (parsePtr->numWords != 2) {
+ return TCL_ERROR;
+ }
+ tokenPtr = TokenAfter(parsePtr->tokenPtr);
+ if (tokenPtr->type != TCL_TOKEN_SIMPLE_WORD) {
+ return TCL_ERROR;
+ }
+
+ /*
+ * Compile the code and convert any error from the compilation into
+ * bytecode reporting the error;
+ */
+
+ if (TCL_ERROR == TclAssembleCode(envPtr, tokenPtr[1].start,
+ tokenPtr[1].size, TCL_EVAL_DIRECT)) {
+
+ Tcl_AppendObjToErrorInfo(interp, Tcl_ObjPrintf(
+ "\n (\"%.*s\" body, line %d)",
+ parsePtr->tokenPtr->size, parsePtr->tokenPtr->start,
+ Tcl_GetErrorLine(interp)));
+ envPtr->numCommands = numCommands;
+ envPtr->codeNext = envPtr->codeStart + offset;
+ envPtr->currStackDepth = depth;
+ TclCompileSyntaxError(interp, envPtr);
+ }
+ return TCL_OK;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * TclAssembleCode --
+ *
+ * Take a list of instructions in a Tcl_Obj, and assemble them to Tcl
+ * bytecodes
+ *
+ * Results:
+ * Returns TCL_OK on success, TCL_ERROR on failure. If 'flags' includes
+ * TCL_EVAL_DIRECT, places an error message in the interpreter result.
+ *
+ * Side effects:
+ * Adds byte codes to the compile environment, and updates the
+ * environment's stack depth.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static int
+TclAssembleCode(
+ CompileEnv *envPtr, /* Compilation environment that is to receive
+ * the generated bytecode */
+ const char* codePtr, /* Assembly-language code to be processed */
+ int codeLen, /* Length of the code */
+ int flags) /* OR'ed combination of flags */
+{
+ Tcl_Interp* interp = (Tcl_Interp*) envPtr->iPtr;
+ /* Tcl interpreter */
+ /*
+ * Walk through the assembly script using the Tcl parser. Each 'command'
+ * will be an instruction or assembly directive.
+ */
+
+ const char* instPtr = codePtr;
+ /* Where to start looking for a line of code */
+ const char* nextPtr; /* Pointer to the end of the line of code */
+ int bytesLeft = codeLen; /* Number of bytes of source code remaining to
+ * be parsed */
+ int status; /* Tcl status return */
+ AssemblyEnv* assemEnvPtr = NewAssemblyEnv(envPtr, flags);
+ Tcl_Parse* parsePtr = assemEnvPtr->parsePtr;
+
+ do {
+ /*
+ * Parse out one command line from the assembly script.
+ */
+
+ status = Tcl_ParseCommand(interp, instPtr, bytesLeft, 0, parsePtr);
+
+ /*
+ * Report errors in the parse.
+ */
+
+ if (status != TCL_OK) {
+ if (flags & TCL_EVAL_DIRECT) {
+ Tcl_LogCommandInfo(interp, codePtr, parsePtr->commandStart,
+ parsePtr->term + 1 - parsePtr->commandStart);
+ }
+ FreeAssemblyEnv(assemEnvPtr);
+ return TCL_ERROR;
+ }
+
+ /*
+ * Advance the pointers around any leading commentary.
+ */
+
+ TclAdvanceLines(&assemEnvPtr->cmdLine, instPtr,
+ parsePtr->commandStart);
+ TclAdvanceContinuations(&assemEnvPtr->cmdLine, &assemEnvPtr->clNext,
+ parsePtr->commandStart - envPtr->source);
+
+ /*
+ * Process the line of code.
+ */
+
+ if (parsePtr->numWords > 0) {
+ int instLen = parsePtr->commandSize;
+ /* Length in bytes of the current command */
+
+ if (parsePtr->term == parsePtr->commandStart + instLen - 1) {
+ --instLen;
+ }
+
+ /*
+ * If tracing, show each line assembled as it happens.
+ */
+
+#ifdef TCL_COMPILE_DEBUG
+ if ((tclTraceCompile >= 2) && (envPtr->procPtr == NULL)) {
+ printf(" %4ld Assembling: ",
+ (long)(envPtr->codeNext - envPtr->codeStart));
+ TclPrintSource(stdout, parsePtr->commandStart,
+ TclMin(instLen, 55));
+ printf("\n");
+ }
+#endif
+ if (AssembleOneLine(assemEnvPtr) != TCL_OK) {
+ if (flags & TCL_EVAL_DIRECT) {
+ Tcl_LogCommandInfo(interp, codePtr,
+ parsePtr->commandStart, instLen);
+ }
+ Tcl_FreeParse(parsePtr);
+ FreeAssemblyEnv(assemEnvPtr);
+ return TCL_ERROR;
+ }
+ }
+
+ /*
+ * Advance to the next line of code.
+ */
+
+ nextPtr = parsePtr->commandStart + parsePtr->commandSize;
+ bytesLeft -= (nextPtr - instPtr);
+ instPtr = nextPtr;
+ TclAdvanceLines(&assemEnvPtr->cmdLine, parsePtr->commandStart,
+ instPtr);
+ TclAdvanceContinuations(&assemEnvPtr->cmdLine, &assemEnvPtr->clNext,
+ instPtr - envPtr->source);
+ Tcl_FreeParse(parsePtr);
+ } while (bytesLeft > 0);
+
+ /*
+ * Done with parsing the code.
+ */
+
+ status = FinishAssembly(assemEnvPtr);
+ FreeAssemblyEnv(assemEnvPtr);
+ return status;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * NewAssemblyEnv --
+ *
+ * Creates an environment for the assembler to run in.
+ *
+ * Results:
+ * Allocates, initialises and returns an assembler environment
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static AssemblyEnv*
+NewAssemblyEnv(
+ CompileEnv* envPtr, /* Compilation environment being used for code
+ * generation*/
+ int flags) /* Compilation flags (TCL_EVAL_DIRECT) */
+{
+ Tcl_Interp* interp = (Tcl_Interp*) envPtr->iPtr;
+ /* Tcl interpreter */
+ AssemblyEnv* assemEnvPtr = (AssemblyEnv*)TclStackAlloc(interp, sizeof(AssemblyEnv));
+ /* Assembler environment under construction */
+ Tcl_Parse* parsePtr = (Tcl_Parse*)TclStackAlloc(interp, sizeof(Tcl_Parse));
+ /* Parse of one line of assembly code */
+
+ assemEnvPtr->envPtr = envPtr;
+ assemEnvPtr->parsePtr = parsePtr;
+ assemEnvPtr->cmdLine = 1;
+ assemEnvPtr->clNext = envPtr->clNext;
+
+ /*
+ * Make the hashtables that store symbol resolution.
+ */
+
+ Tcl_InitHashTable(&assemEnvPtr->labelHash, TCL_STRING_KEYS);
+
+ /*
+ * Start the first basic block.
+ */
+
+ assemEnvPtr->curr_bb = NULL;
+ assemEnvPtr->head_bb = AllocBB(assemEnvPtr);
+ assemEnvPtr->curr_bb = assemEnvPtr->head_bb;
+ assemEnvPtr->head_bb->startLine = 1;
+
+ /*
+ * Stash compilation flags.
+ */
+
+ assemEnvPtr->flags = flags;
+ return assemEnvPtr;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * FreeAssemblyEnv --
+ *
+ * Cleans up the assembler environment when assembly is complete.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static void
+FreeAssemblyEnv(
+ AssemblyEnv* assemEnvPtr) /* Environment to free */
+{
+ CompileEnv* envPtr = assemEnvPtr->envPtr;
+ /* Compilation environment being used for code
+ * generation */
+ Tcl_Interp* interp = (Tcl_Interp*) envPtr->iPtr;
+ /* Tcl interpreter */
+ BasicBlock* thisBB; /* Pointer to a basic block being deleted */
+ BasicBlock* nextBB; /* Pointer to a deleted basic block's
+ * successor */
+
+ /*
+ * Free all the basic block structures.
+ */
+
+ for (thisBB = assemEnvPtr->head_bb; thisBB != NULL; thisBB = nextBB) {
+ if (thisBB->jumpTarget != NULL) {
+ Tcl_DecrRefCount(thisBB->jumpTarget);
+ }
+ if (thisBB->foreignExceptions != NULL) {
+ ckfree(thisBB->foreignExceptions);
+ }
+ nextBB = thisBB->successor1;
+ if (thisBB->jtPtr != NULL) {
+ DeleteMirrorJumpTable(thisBB->jtPtr);
+ thisBB->jtPtr = NULL;
+ }
+ ckfree(thisBB);
+ }
+
+ /*
+ * Dispose what's left.
+ */
+
+ Tcl_DeleteHashTable(&assemEnvPtr->labelHash);
+ TclStackFree(interp, assemEnvPtr->parsePtr);
+ TclStackFree(interp, assemEnvPtr);
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * AssembleOneLine --
+ *
+ * Assembles a single command from an assembly language source.
+ *
+ * Results:
+ * Returns TCL_ERROR with an appropriate error message if the assembly
+ * fails. Returns TCL_OK if the assembly succeeds. Updates the assembly
+ * environment with the state of the assembly.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static int
+AssembleOneLine(
+ AssemblyEnv* assemEnvPtr) /* State of the assembly */
+{
+ CompileEnv* envPtr = assemEnvPtr->envPtr;
+ /* Compilation environment being used for code
+ * gen */
+ Tcl_Interp* interp = (Tcl_Interp*) envPtr->iPtr;
+ /* Tcl interpreter */
+ Tcl_Parse* parsePtr = assemEnvPtr->parsePtr;
+ /* Parse of the line of code */
+ Tcl_Token* tokenPtr; /* Current token within the line of code */
+ Tcl_Obj* instNameObj; /* Name of the instruction */
+ int tblIdx; /* Index in TalInstructionTable of the
+ * instruction */
+ enum TalInstType instType; /* Type of the instruction */
+ Tcl_Obj* operand1Obj = NULL;
+ /* First operand to the instruction */
+ const char* operand1; /* String rep of the operand */
+ int operand1Len; /* String length of the operand */
+ int opnd; /* Integer representation of an operand */
+ int litIndex; /* Literal pool index of a constant */
+ int localVar; /* LVT index of a local variable */
+ int flags; /* Flags for a basic block */
+ JumptableInfo* jtPtr; /* Pointer to a jumptable */
+ int infoIndex; /* Index of the jumptable in auxdata */
+ int status = TCL_ERROR; /* Return value from this function */
+
+ /*
+ * Make sure that the instruction name is known at compile time.
+ */
+
+ tokenPtr = parsePtr->tokenPtr;
+ if (GetNextOperand(assemEnvPtr, &tokenPtr, &instNameObj) != TCL_OK) {
+ return TCL_ERROR;
+ }
+
+ /*
+ * Look up the instruction name.
+ */
+
+ if (Tcl_GetIndexFromObjStruct(interp, instNameObj,
+ &TalInstructionTable[0].name, sizeof(TalInstDesc), "instruction",
+ TCL_EXACT, &tblIdx) != TCL_OK) {
+ goto cleanup;
+ }
+
+ /*
+ * Vector on the type of instruction being processed.
+ */
+
+ instType = TalInstructionTable[tblIdx].instType;
+ switch (instType) {
+
+ case ASSEM_PUSH:
+ if (parsePtr->numWords != 2) {
+ Tcl_WrongNumArgs(interp, 1, &instNameObj, "value");
+ goto cleanup;
+ }
+ if (GetNextOperand(assemEnvPtr, &tokenPtr, &operand1Obj) != TCL_OK) {
+ goto cleanup;
+ }
+ operand1 = Tcl_GetStringFromObj(operand1Obj, &operand1Len);
+ litIndex = TclRegisterNewLiteral(envPtr, operand1, operand1Len);
+ BBEmitInst1or4(assemEnvPtr, tblIdx, litIndex, 0);
+ break;
+
+ case ASSEM_1BYTE:
+ if (parsePtr->numWords != 1) {
+ Tcl_WrongNumArgs(interp, 1, &instNameObj, "");
+ goto cleanup;
+ }
+ BBEmitOpcode(assemEnvPtr, tblIdx, 0);
+ break;
+
+ case ASSEM_BEGIN_CATCH:
+ /*
+ * Emit the BEGIN_CATCH instruction with the code offset of the
+ * exception branch target instead of the exception range index. The
+ * correct index will be generated and inserted later, when catches
+ * are being resolved.
+ */
+
+ if (parsePtr->numWords != 2) {
+ Tcl_WrongNumArgs(interp, 1, &instNameObj, "label");
+ goto cleanup;
+ }
+ if (GetNextOperand(assemEnvPtr, &tokenPtr, &operand1Obj) != TCL_OK) {
+ goto cleanup;
+ }
+ assemEnvPtr->curr_bb->jumpLine = assemEnvPtr->cmdLine;
+ assemEnvPtr->curr_bb->jumpOffset = envPtr->codeNext-envPtr->codeStart;
+ BBEmitInstInt4(assemEnvPtr, tblIdx, 0, 0);
+ assemEnvPtr->curr_bb->flags |= BB_BEGINCATCH;
+ StartBasicBlock(assemEnvPtr, BB_FALLTHRU, operand1Obj);
+ break;
+
+ case ASSEM_BOOL:
+ if (parsePtr->numWords != 2) {
+ Tcl_WrongNumArgs(interp, 1, &instNameObj, "boolean");
+ goto cleanup;
+ }
+ if (GetBooleanOperand(assemEnvPtr, &tokenPtr, &opnd) != TCL_OK) {
+ goto cleanup;
+ }
+ BBEmitInstInt1(assemEnvPtr, tblIdx, opnd, 0);
+ break;
+
+ case ASSEM_BOOL_LVT4:
+ if (parsePtr->numWords != 3) {
+ Tcl_WrongNumArgs(interp, 1, &instNameObj, "boolean varName");
+ goto cleanup;
+ }
+ if (GetBooleanOperand(assemEnvPtr, &tokenPtr, &opnd) != TCL_OK) {
+ goto cleanup;
+ }
+ localVar = FindLocalVar(assemEnvPtr, &tokenPtr);
+ if (localVar < 0) {
+ goto cleanup;
+ }
+ BBEmitInstInt1(assemEnvPtr, tblIdx, opnd, 0);
+ TclEmitInt4(localVar, envPtr);
+ break;
+
+ case ASSEM_CLOCK_READ:
+ if (parsePtr->numWords != 2) {
+ Tcl_WrongNumArgs(interp, 1, &instNameObj, "imm8");
+ goto cleanup;
+ }
+ if (GetIntegerOperand(assemEnvPtr, &tokenPtr, &opnd) != TCL_OK) {
+ goto cleanup;
+ }
+ if (opnd < 0 || opnd > 3) {
+ Tcl_SetObjResult(interp,
+ Tcl_NewStringObj("operand must be [0..3]", -1));
+ Tcl_SetErrorCode(interp, "TCL", "ASSEM", "OPERAND<0,>3", NULL);
+ goto cleanup;
+ }
+ BBEmitInstInt1(assemEnvPtr, tblIdx, opnd, opnd);
+ break;
+
+ case ASSEM_CONCAT1:
+ if (parsePtr->numWords != 2) {
+ Tcl_WrongNumArgs(interp, 1, &instNameObj, "imm8");
+ goto cleanup;
+ }
+ if (GetIntegerOperand(assemEnvPtr, &tokenPtr, &opnd) != TCL_OK
+ || CheckOneByte(interp, opnd) != TCL_OK
+ || CheckStrictlyPositive(interp, opnd) != TCL_OK) {
+ goto cleanup;
+ }
+ BBEmitInstInt1(assemEnvPtr, tblIdx, opnd, opnd);
+ break;
+
+ case ASSEM_DICT_GET:
+ if (parsePtr->numWords != 2) {
+ Tcl_WrongNumArgs(interp, 1, &instNameObj, "count");
+ goto cleanup;
+ }
+ if (GetIntegerOperand(assemEnvPtr, &tokenPtr, &opnd) != TCL_OK
+ || CheckStrictlyPositive(interp, opnd) != TCL_OK) {
+ goto cleanup;
+ }
+ BBEmitInstInt4(assemEnvPtr, tblIdx, opnd, opnd+1);
+ break;
+
+ case ASSEM_DICT_SET:
+ if (parsePtr->numWords != 3) {
+ Tcl_WrongNumArgs(interp, 1, &instNameObj, "count varName");
+ goto cleanup;
+ }
+ if (GetIntegerOperand(assemEnvPtr, &tokenPtr, &opnd) != TCL_OK
+ || CheckStrictlyPositive(interp, opnd) != TCL_OK) {
+ goto cleanup;
+ }
+ localVar = FindLocalVar(assemEnvPtr, &tokenPtr);
+ if (localVar < 0) {
+ goto cleanup;
+ }
+ BBEmitInstInt4(assemEnvPtr, tblIdx, opnd, opnd+1);
+ TclEmitInt4(localVar, envPtr);
+ break;
+
+ case ASSEM_DICT_UNSET:
+ if (parsePtr->numWords != 3) {
+ Tcl_WrongNumArgs(interp, 1, &instNameObj, "count varName");
+ goto cleanup;
+ }
+ if (GetIntegerOperand(assemEnvPtr, &tokenPtr, &opnd) != TCL_OK
+ || CheckStrictlyPositive(interp, opnd) != TCL_OK) {
+ goto cleanup;
+ }
+ localVar = FindLocalVar(assemEnvPtr, &tokenPtr);
+ if (localVar < 0) {
+ goto cleanup;
+ }
+ BBEmitInstInt4(assemEnvPtr, tblIdx, opnd, opnd);
+ TclEmitInt4(localVar, envPtr);
+ break;
+
+ case ASSEM_END_CATCH:
+ if (parsePtr->numWords != 1) {
+ Tcl_WrongNumArgs(interp, 1, &instNameObj, "");
+ goto cleanup;
+ }
+ assemEnvPtr->curr_bb->flags |= BB_ENDCATCH;
+ BBEmitOpcode(assemEnvPtr, tblIdx, 0);
+ StartBasicBlock(assemEnvPtr, BB_FALLTHRU, NULL);
+ break;
+
+ case ASSEM_EVAL:
+ /* TODO - Refactor this stuff into a subroutine that takes the inst
+ * code, the message ("script" or "expression") and an evaluator
+ * callback that calls TclCompileScript or TclCompileExpr. */
+
+ if (parsePtr->numWords != 2) {
+ Tcl_WrongNumArgs(interp, 1, &instNameObj,
+ ((TalInstructionTable[tblIdx].tclInstCode
+ == INST_EVAL_STK) ? "script" : "expression"));
+ goto cleanup;
+ }
+ if (tokenPtr->type == TCL_TOKEN_SIMPLE_WORD) {
+ CompileEmbeddedScript(assemEnvPtr, tokenPtr+1,
+ TalInstructionTable+tblIdx);
+ } else if (GetNextOperand(assemEnvPtr, &tokenPtr,
+ &operand1Obj) != TCL_OK) {
+ goto cleanup;
+ } else {
+ operand1 = Tcl_GetStringFromObj(operand1Obj, &operand1Len);
+ litIndex = TclRegisterNewLiteral(envPtr, operand1, operand1Len);
+
+ /*
+ * Assumes that PUSH is the first slot!
+ */
+
+ BBEmitInst1or4(assemEnvPtr, 0, litIndex, 0);
+ BBEmitOpcode(assemEnvPtr, tblIdx, 0);
+ }
+ break;
+
+ case ASSEM_INVOKE:
+ if (parsePtr->numWords != 2) {
+ Tcl_WrongNumArgs(interp, 1, &instNameObj, "count");
+ goto cleanup;
+ }
+ if (GetIntegerOperand(assemEnvPtr, &tokenPtr, &opnd) != TCL_OK
+ || CheckStrictlyPositive(interp, opnd) != TCL_OK) {
+ goto cleanup;
+ }
+
+ BBEmitInst1or4(assemEnvPtr, tblIdx, opnd, opnd);
+ break;
+
+ case ASSEM_JUMP:
+ case ASSEM_JUMP4:
+ if (parsePtr->numWords != 2) {
+ Tcl_WrongNumArgs(interp, 1, &instNameObj, "label");
+ goto cleanup;
+ }
+ if (GetNextOperand(assemEnvPtr, &tokenPtr, &operand1Obj) != TCL_OK) {
+ goto cleanup;
+ }
+ assemEnvPtr->curr_bb->jumpOffset = envPtr->codeNext-envPtr->codeStart;
+ if (instType == ASSEM_JUMP) {
+ flags = BB_JUMP1;
+ BBEmitInstInt1(assemEnvPtr, tblIdx, 0, 0);
+ } else {
+ flags = 0;
+ BBEmitInstInt4(assemEnvPtr, tblIdx, 0, 0);
+ }
+
+ /*
+ * Start a new basic block at the instruction following the jump.
+ */
+
+ assemEnvPtr->curr_bb->jumpLine = assemEnvPtr->cmdLine;
+ if (TalInstructionTable[tblIdx].operandsConsumed != 0) {
+ flags |= BB_FALLTHRU;
+ }
+ StartBasicBlock(assemEnvPtr, flags, operand1Obj);
+ break;
+
+ case ASSEM_JUMPTABLE:
+ if (parsePtr->numWords != 2) {
+ Tcl_WrongNumArgs(interp, 1, &instNameObj, "table");
+ goto cleanup;
+ }
+ if (GetNextOperand(assemEnvPtr, &tokenPtr, &operand1Obj) != TCL_OK) {
+ goto cleanup;
+ }
+
+ jtPtr = (JumptableInfo*)ckalloc(sizeof(JumptableInfo));
+
+ Tcl_InitHashTable(&jtPtr->hashTable, TCL_STRING_KEYS);
+ assemEnvPtr->curr_bb->jumpLine = assemEnvPtr->cmdLine;
+ assemEnvPtr->curr_bb->jumpOffset = envPtr->codeNext-envPtr->codeStart;
+ DEBUG_PRINT("bb %p jumpLine %d jumpOffset %d\n",
+ assemEnvPtr->curr_bb, assemEnvPtr->cmdLine,
+ envPtr->codeNext - envPtr->codeStart);
+
+ infoIndex = TclCreateAuxData(jtPtr, &tclJumptableInfoType, envPtr);
+ DEBUG_PRINT("auxdata index=%d\n", infoIndex);
+
+ BBEmitInstInt4(assemEnvPtr, tblIdx, infoIndex, 0);
+ if (CreateMirrorJumpTable(assemEnvPtr, operand1Obj) != TCL_OK) {
+ goto cleanup;
+ }
+ StartBasicBlock(assemEnvPtr, BB_JUMPTABLE|BB_FALLTHRU, NULL);
+ break;
+
+ case ASSEM_LABEL:
+ if (parsePtr->numWords != 2) {
+ Tcl_WrongNumArgs(interp, 1, &instNameObj, "name");
+ goto cleanup;
+ }
+ if (GetNextOperand(assemEnvPtr, &tokenPtr, &operand1Obj) != TCL_OK) {
+ goto cleanup;
+ }
+
+ /*
+ * Add the (label_name, address) pair to the hash table.
+ */
+
+ if (DefineLabel(assemEnvPtr, Tcl_GetString(operand1Obj)) != TCL_OK) {
+ goto cleanup;
+ }
+ break;
+
+ case ASSEM_LINDEX_MULTI:
+ if (parsePtr->numWords != 2) {
+ Tcl_WrongNumArgs(interp, 1, &instNameObj, "count");
+ goto cleanup;
+ }
+ if (GetIntegerOperand(assemEnvPtr, &tokenPtr, &opnd) != TCL_OK
+ || CheckStrictlyPositive(interp, opnd) != TCL_OK) {
+ goto cleanup;
+ }
+ BBEmitInstInt4(assemEnvPtr, tblIdx, opnd, opnd);
+ break;
+
+ case ASSEM_LIST:
+ if (parsePtr->numWords != 2) {
+ Tcl_WrongNumArgs(interp, 1, &instNameObj, "count");
+ goto cleanup;
+ }
+ if (GetIntegerOperand(assemEnvPtr, &tokenPtr, &opnd) != TCL_OK
+ || CheckNonNegative(interp, opnd) != TCL_OK) {
+ goto cleanup;
+ }
+ BBEmitInstInt4(assemEnvPtr, tblIdx, opnd, opnd);
+ break;
+
+ case ASSEM_INDEX:
+ if (parsePtr->numWords != 2) {
+ Tcl_WrongNumArgs(interp, 1, &instNameObj, "count");
+ goto cleanup;
+ }
+ if (GetListIndexOperand(assemEnvPtr, &tokenPtr, &opnd) != TCL_OK) {
+ goto cleanup;
+ }
+ BBEmitInstInt4(assemEnvPtr, tblIdx, opnd, opnd);
+ break;
+
+ case ASSEM_LSET_FLAT:
+ if (parsePtr->numWords != 2) {
+ Tcl_WrongNumArgs(interp, 1, &instNameObj, "count");
+ goto cleanup;
+ }
+ if (GetIntegerOperand(assemEnvPtr, &tokenPtr, &opnd) != TCL_OK) {
+ goto cleanup;
+ }
+ if (opnd < 2) {
+ if (assemEnvPtr->flags & TCL_EVAL_DIRECT) {
+ Tcl_SetObjResult(interp,
+ Tcl_NewStringObj("operand must be >=2", -1));
+ Tcl_SetErrorCode(interp, "TCL", "ASSEM", "OPERAND>=2", NULL);
+ }
+ goto cleanup;
+ }
+ BBEmitInstInt4(assemEnvPtr, tblIdx, opnd, opnd);
+ break;
+
+ case ASSEM_LVT:
+ if (parsePtr->numWords != 2) {
+ Tcl_WrongNumArgs(interp, 1, &instNameObj, "varname");
+ goto cleanup;
+ }
+ localVar = FindLocalVar(assemEnvPtr, &tokenPtr);
+ if (localVar < 0) {
+ goto cleanup;
+ }
+ BBEmitInst1or4(assemEnvPtr, tblIdx, localVar, 0);
+ break;
+
+ case ASSEM_LVT1:
+ if (parsePtr->numWords != 2) {
+ Tcl_WrongNumArgs(interp, 1, &instNameObj, "varname");
+ goto cleanup;
+ }
+ localVar = FindLocalVar(assemEnvPtr, &tokenPtr);
+ if (localVar < 0 || CheckOneByte(interp, localVar)) {
+ goto cleanup;
+ }
+ BBEmitInstInt1(assemEnvPtr, tblIdx, localVar, 0);
+ break;
+
+ case ASSEM_LVT1_SINT1:
+ if (parsePtr->numWords != 3) {
+ Tcl_WrongNumArgs(interp, 1, &instNameObj, "varName imm8");
+ goto cleanup;
+ }
+ localVar = FindLocalVar(assemEnvPtr, &tokenPtr);
+ if (localVar < 0 || CheckOneByte(interp, localVar)
+ || GetIntegerOperand(assemEnvPtr, &tokenPtr, &opnd) != TCL_OK
+ || CheckSignedOneByte(interp, opnd)) {
+ goto cleanup;
+ }
+ BBEmitInstInt1(assemEnvPtr, tblIdx, localVar, 0);
+ TclEmitInt1(opnd, envPtr);
+ break;
+
+ case ASSEM_LVT4:
+ if (parsePtr->numWords != 2) {
+ Tcl_WrongNumArgs(interp, 1, &instNameObj, "varname");
+ goto cleanup;
+ }
+ localVar = FindLocalVar(assemEnvPtr, &tokenPtr);
+ if (localVar < 0) {
+ goto cleanup;
+ }
+ BBEmitInstInt4(assemEnvPtr, tblIdx, localVar, 0);
+ break;
+
+ case ASSEM_OVER:
+ if (parsePtr->numWords != 2) {
+ Tcl_WrongNumArgs(interp, 1, &instNameObj, "count");
+ goto cleanup;
+ }
+ if (GetIntegerOperand(assemEnvPtr, &tokenPtr, &opnd) != TCL_OK
+ || CheckNonNegative(interp, opnd) != TCL_OK) {
+ goto cleanup;
+ }
+ BBEmitInstInt4(assemEnvPtr, tblIdx, opnd, opnd+1);
+ break;
+
+ case ASSEM_REGEXP:
+ if (parsePtr->numWords != 2) {
+ Tcl_WrongNumArgs(interp, 1, &instNameObj, "boolean");
+ goto cleanup;
+ }
+ if (GetBooleanOperand(assemEnvPtr, &tokenPtr, &opnd) != TCL_OK) {
+ goto cleanup;
+ }
+ {
+ BBEmitInstInt1(assemEnvPtr, tblIdx, TCL_REG_ADVANCED | (opnd ? TCL_REG_NOCASE : 0), 0);
+ }
+ break;
+
+ case ASSEM_REVERSE:
+ if (parsePtr->numWords != 2) {
+ Tcl_WrongNumArgs(interp, 1, &instNameObj, "count");
+ goto cleanup;
+ }
+ if (GetIntegerOperand(assemEnvPtr, &tokenPtr, &opnd) != TCL_OK
+ || CheckNonNegative(interp, opnd) != TCL_OK) {
+ goto cleanup;
+ }
+ BBEmitInstInt4(assemEnvPtr, tblIdx, opnd, opnd);
+ break;
+
+ case ASSEM_SINT1:
+ if (parsePtr->numWords != 2) {
+ Tcl_WrongNumArgs(interp, 1, &instNameObj, "imm8");
+ goto cleanup;
+ }
+ if (GetIntegerOperand(assemEnvPtr, &tokenPtr, &opnd) != TCL_OK
+ || CheckSignedOneByte(interp, opnd) != TCL_OK) {
+ goto cleanup;
+ }
+ BBEmitInstInt1(assemEnvPtr, tblIdx, opnd, 0);
+ break;
+
+ case ASSEM_SINT4_LVT4:
+ if (parsePtr->numWords != 3) {
+ Tcl_WrongNumArgs(interp, 1, &instNameObj, "count varName");
+ goto cleanup;
+ }
+ if (GetIntegerOperand(assemEnvPtr, &tokenPtr, &opnd) != TCL_OK) {
+ goto cleanup;
+ }
+ localVar = FindLocalVar(assemEnvPtr, &tokenPtr);
+ if (localVar < 0) {
+ goto cleanup;
+ }
+ BBEmitInstInt4(assemEnvPtr, tblIdx, opnd, 0);
+ TclEmitInt4(localVar, envPtr);
+ break;
+
+ default:
+ Tcl_Panic("Instruction \"%s\" could not be found, can't happen\n",
+ Tcl_GetString(instNameObj));
+ }
+
+ status = TCL_OK;
+ cleanup:
+ Tcl_DecrRefCount(instNameObj);
+ if (operand1Obj) {
+ Tcl_DecrRefCount(operand1Obj);
+ }
+ return status;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * CompileEmbeddedScript --
+ *
+ * Compile an embedded 'eval' or 'expr' that appears in assembly code.
+ *
+ * This procedure is called when the 'eval' or 'expr' assembly directive is
+ * encountered, and the argument to the directive is a simple word that
+ * requires no substitution. The appropriate compiler (TclCompileScript or
+ * TclCompileExpr) is invoked recursively, and emits bytecode.
+ *
+ * Before the compiler is invoked, the compilation environment's stack
+ * consumption is reset to zero. Upon return from the compilation, the net
+ * stack effect of the compilation is in the compiler env, and this stack
+ * effect is posted to the assembler environment. The compile environment's
+ * stack consumption is then restored to what it was before (which is actually
+ * the state of the stack on entry to the block of assembly code).
+ *
+ * Any exception ranges pushed by the compilation are copied to the basic
+ * block and removed from the compiler environment. They will be rebuilt at
+ * the end of assembly, when the exception stack depth is actually known.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static void
+CompileEmbeddedScript(
+ AssemblyEnv* assemEnvPtr, /* Assembly environment */
+ Tcl_Token* tokenPtr, /* Tcl_Token containing the script */
+ const TalInstDesc* instPtr) /* Instruction that determines whether
+ * the script is 'expr' or 'eval' */
+{
+ CompileEnv* envPtr = assemEnvPtr->envPtr;
+ /* Compilation environment */
+ Tcl_Interp* interp = (Tcl_Interp*) envPtr->iPtr;
+ /* Tcl interpreter */
+
+ /*
+ * The expression or script is not only known at compile time, but
+ * actually a "simple word". It can be compiled inline by invoking the
+ * compiler recursively.
+ *
+ * Save away the stack depth and reset it before compiling the script.
+ * We'll record the stack usage of the script in the BasicBlock, and
+ * accumulate it together with the stack usage of the enclosing assembly
+ * code.
+ */
+
+ int savedStackDepth = envPtr->currStackDepth;
+ int savedMaxStackDepth = envPtr->maxStackDepth;
+ int savedExceptArrayNext = envPtr->exceptArrayNext;
+
+ envPtr->currStackDepth = 0;
+ envPtr->maxStackDepth = 0;
+
+ StartBasicBlock(assemEnvPtr, BB_FALLTHRU, NULL);
+ switch(instPtr->tclInstCode) {
+ case INST_EVAL_STK:
+ TclCompileScript(interp, tokenPtr->start, tokenPtr->size, envPtr);
+ break;
+ case INST_EXPR_STK:
+ TclCompileExpr(interp, tokenPtr->start, tokenPtr->size, envPtr, 1);
+ break;
+ default:
+ Tcl_Panic("no ASSEM_EVAL case for %s (%d), can't happen",
+ instPtr->name, instPtr->tclInstCode);
+ }
+
+ /*
+ * Roll up the stack usage of the embedded block into the assembler
+ * environment.
+ */
+
+ SyncStackDepth(assemEnvPtr);
+ envPtr->currStackDepth = savedStackDepth;
+ envPtr->maxStackDepth = savedMaxStackDepth;
+
+ /*
+ * Save any exception ranges that were pushed by the compiler; they will
+ * need to be fixed up once the stack depth is known.
+ */
+
+ MoveExceptionRangesToBasicBlock(assemEnvPtr, savedExceptArrayNext);
+
+ /*
+ * Flush the current basic block.
+ */
+
+ StartBasicBlock(assemEnvPtr, BB_FALLTHRU, NULL);
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * SyncStackDepth --
+ *
+ * Copies the stack depth from the compile environment to a basic block.
+ *
+ * Side effects:
+ * Current and max stack depth in the current basic block are adjusted.
+ *
+ * This procedure is called on return from invoking the compiler for the
+ * 'eval' and 'expr' operations. It adjusts the stack depth of the current
+ * basic block to reflect the stack required by the just-compiled code.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static void
+SyncStackDepth(
+ AssemblyEnv* assemEnvPtr) /* Assembly environment */
+{
+ CompileEnv* envPtr = assemEnvPtr->envPtr;
+ /* Compilation environment */
+ BasicBlock* curr_bb = assemEnvPtr->curr_bb;
+ /* Current basic block */
+ int maxStackDepth = curr_bb->finalStackDepth + envPtr->maxStackDepth;
+ /* Max stack depth in the basic block */
+
+ if (maxStackDepth > curr_bb->maxStackDepth) {
+ curr_bb->maxStackDepth = maxStackDepth;
+ }
+ curr_bb->finalStackDepth += envPtr->currStackDepth;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * MoveExceptionRangesToBasicBlock --
+ *
+ * Removes exception ranges that were created by compiling an embedded
+ * script from the CompileEnv, and stores them in the BasicBlock. They
+ * will be reinstalled, at the correct stack depth, after control flow
+ * analysis is complete on the assembly code.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static void
+MoveExceptionRangesToBasicBlock(
+ AssemblyEnv* assemEnvPtr, /* Assembly environment */
+ int savedExceptArrayNext) /* Saved index of the end of the exception
+ * range array */
+{
+ CompileEnv* envPtr = assemEnvPtr->envPtr;
+ /* Compilation environment */
+ BasicBlock* curr_bb = assemEnvPtr->curr_bb;
+ /* Current basic block */
+ int exceptionCount = envPtr->exceptArrayNext - savedExceptArrayNext;
+ /* Number of ranges that must be moved */
+ int i;
+
+ if (exceptionCount == 0) {
+ /* Nothing to do */
+ return;
+ }
+
+ /*
+ * Save the exception ranges in the basic block. They will be re-added at
+ * the conclusion of assembly; at this time, the INST_BEGIN_CATCH
+ * instructions in the block will be adjusted from whatever range indices
+ * they have [savedExceptArrayNext .. envPtr->exceptArrayNext) to the
+ * indices that the exceptions acquire. The saved exception ranges are
+ * converted to a relative nesting depth. The depth will be recomputed
+ * once flow analysis has determined the actual stack depth of the block.
+ */
+
+ DEBUG_PRINT("basic block %p has %d exceptions starting at %d\n",
+ curr_bb, exceptionCount, savedExceptArrayNext);
+ curr_bb->foreignExceptionBase = savedExceptArrayNext;
+ curr_bb->foreignExceptionCount = exceptionCount;
+ curr_bb->foreignExceptions =
+ (ExceptionRange*)ckalloc(exceptionCount * sizeof(ExceptionRange));
+ memcpy(curr_bb->foreignExceptions,
+ envPtr->exceptArrayPtr + savedExceptArrayNext,
+ exceptionCount * sizeof(ExceptionRange));
+ for (i = 0; i < exceptionCount; ++i) {
+ curr_bb->foreignExceptions[i].nestingLevel -= envPtr->exceptDepth;
+ }
+ envPtr->exceptArrayNext = savedExceptArrayNext;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * CreateMirrorJumpTable --
+ *
+ * Makes a jump table with comparison values and assembly code labels.
+ *
+ * Results:
+ * Returns a standard Tcl status, with an error message in the
+ * interpreter on error.
+ *
+ * Side effects:
+ * Initializes the jump table pointer in the current basic block to a
+ * JumptableInfo. The keys in the JumptableInfo are the comparison
+ * strings. The values, instead of being jump displacements, are
+ * Tcl_Obj's with the code labels.
+ */
+
+static int
+CreateMirrorJumpTable(
+ AssemblyEnv* assemEnvPtr, /* Assembly environment */
+ Tcl_Obj* jumps) /* List of alternating keywords and labels */
+{
+ int objc; /* Number of elements in the 'jumps' list */
+ Tcl_Obj** objv; /* Pointers to the elements in the list */
+ CompileEnv* envPtr = assemEnvPtr->envPtr;
+ /* Compilation environment */
+ Tcl_Interp* interp = (Tcl_Interp*) envPtr->iPtr;
+ /* Tcl interpreter */
+ BasicBlock* bbPtr = assemEnvPtr->curr_bb;
+ /* Current basic block */
+ JumptableInfo* jtPtr;
+ Tcl_HashTable* jtHashPtr; /* Hashtable in the JumptableInfo */
+ Tcl_HashEntry* hashEntry; /* Entry for a key in the hashtable */
+ int isNew; /* Flag==1 if the key is not yet in the
+ * table. */
+ int i;
+
+ if (Tcl_ListObjGetElements(interp, jumps, &objc, &objv) != TCL_OK) {
+ return TCL_ERROR;
+ }
+ if (objc % 2 != 0) {
+ if (assemEnvPtr->flags & TCL_EVAL_DIRECT) {
+ Tcl_SetObjResult(interp, Tcl_NewStringObj(
+ "jump table must have an even number of list elements",
+ -1));
+ Tcl_SetErrorCode(interp, "TCL", "ASSEM", "BADJUMPTABLE", NULL);
+ }
+ return TCL_ERROR;
+ }
+
+ /*
+ * Allocate the jumptable.
+ */
+
+ jtPtr = (JumptableInfo*)ckalloc(sizeof(JumptableInfo));
+ jtHashPtr = &jtPtr->hashTable;
+ Tcl_InitHashTable(jtHashPtr, TCL_STRING_KEYS);
+
+ /*
+ * Fill the keys and labels into the table.
+ */
+
+ DEBUG_PRINT("jump table {\n");
+ for (i = 0; i < objc; i+=2) {
+ DEBUG_PRINT(" %s -> %s\n", Tcl_GetString(objv[i]),
+ Tcl_GetString(objv[i+1]));
+ hashEntry = Tcl_CreateHashEntry(jtHashPtr, Tcl_GetString(objv[i]),
+ &isNew);
+ if (!isNew) {
+ if (assemEnvPtr->flags & TCL_EVAL_DIRECT) {
+ Tcl_SetObjResult(interp, Tcl_ObjPrintf(
+ "duplicate entry in jump table for \"%s\"",
+ Tcl_GetString(objv[i])));
+ Tcl_SetErrorCode(interp, "TCL", "ASSEM", "DUPJUMPTABLEENTRY");
+ DeleteMirrorJumpTable(jtPtr);
+ return TCL_ERROR;
+ }
+ }
+ Tcl_SetHashValue(hashEntry, objv[i+1]);
+ Tcl_IncrRefCount(objv[i+1]);
+ }
+ DEBUG_PRINT("}\n");
+
+ /*
+ * Put the mirror jumptable in the basic block struct.
+ */
+
+ bbPtr->jtPtr = jtPtr;
+ return TCL_OK;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * DeleteMirrorJumpTable --
+ *
+ * Cleans up a jump table when the basic block is deleted.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static void
+DeleteMirrorJumpTable(
+ JumptableInfo* jtPtr)
+{
+ Tcl_HashTable* jtHashPtr = &jtPtr->hashTable;
+ /* Hash table pointer */
+ Tcl_HashSearch search; /* Hash search control */
+ Tcl_HashEntry* entry; /* Hash table entry containing a jump label */
+ Tcl_Obj* label; /* Jump label from the hash table */
+
+ for (entry = Tcl_FirstHashEntry(jtHashPtr, &search);
+ entry != NULL;
+ entry = Tcl_NextHashEntry(&search)) {
+ label = (Tcl_Obj*)Tcl_GetHashValue(entry);
+ Tcl_DecrRefCount(label);
+ Tcl_SetHashValue(entry, NULL);
+ }
+ Tcl_DeleteHashTable(jtHashPtr);
+ ckfree(jtPtr);
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * GetNextOperand --
+ *
+ * Retrieves the next operand in sequence from an assembly instruction,
+ * and makes sure that its value is known at compile time.
+ *
+ * Results:
+ * If successful, returns TCL_OK and leaves a Tcl_Obj with the operand
+ * text in *operandObjPtr. In case of failure, returns TCL_ERROR and
+ * leaves *operandObjPtr untouched.
+ *
+ * Side effects:
+ * Advances *tokenPtrPtr around the token just processed.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static int
+GetNextOperand(
+ AssemblyEnv* assemEnvPtr, /* Assembly environment */
+ Tcl_Token** tokenPtrPtr, /* INPUT/OUTPUT: Pointer to the token holding
+ * the operand */
+ Tcl_Obj** operandObjPtr) /* OUTPUT: Tcl object holding the operand text
+ * with \-substitutions done. */
+{
+ Tcl_Interp* interp = (Tcl_Interp*) assemEnvPtr->envPtr->iPtr;
+ Tcl_Obj* operandObj;
+
+ TclNewObj(operandObj);
+ if (!TclWordKnownAtCompileTime(*tokenPtrPtr, operandObj)) {
+ Tcl_DecrRefCount(operandObj);
+ if (assemEnvPtr->flags & TCL_EVAL_DIRECT) {
+ Tcl_SetObjResult(interp, Tcl_NewStringObj(
+ "assembly code may not contain substitutions", -1));
+ Tcl_SetErrorCode(interp, "TCL", "ASSEM", "NOSUBST", NULL);
+ }
+ return TCL_ERROR;
+ }
+ *tokenPtrPtr = TokenAfter(*tokenPtrPtr);
+ Tcl_IncrRefCount(operandObj);
+ *operandObjPtr = operandObj;
+ return TCL_OK;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * GetBooleanOperand --
+ *
+ * Retrieves a Boolean operand from the input stream and advances
+ * the token pointer.
+ *
+ * Results:
+ * Returns a standard Tcl result (with an error message in the
+ * interpreter on failure).
+ *
+ * Side effects:
+ * Stores the Boolean value in (*result) and advances (*tokenPtrPtr)
+ * to the next token.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static int
+GetBooleanOperand(
+ AssemblyEnv* assemEnvPtr, /* Assembly environment */
+ Tcl_Token** tokenPtrPtr, /* Current token from the parser */
+ int* result) /* OUTPUT: Integer extracted from the token */
+{
+ CompileEnv* envPtr = assemEnvPtr->envPtr;
+ /* Compilation environment */
+ Tcl_Interp* interp = (Tcl_Interp*) envPtr->iPtr;
+ /* Tcl interpreter */
+ Tcl_Token* tokenPtr = *tokenPtrPtr;
+ /* INOUT: Pointer to the next token in the
+ * source code */
+ Tcl_Obj* intObj; /* Integer from the source code */
+ int status; /* Tcl status return */
+
+ /*
+ * Extract the next token as a string.
+ */
+
+ if (GetNextOperand(assemEnvPtr, tokenPtrPtr, &intObj) != TCL_OK) {
+ return TCL_ERROR;
+ }
+
+ /*
+ * Convert to an integer, advance to the next token and return.
+ */
+
+ status = Tcl_GetBooleanFromObj(interp, intObj, result);
+ Tcl_DecrRefCount(intObj);
+ *tokenPtrPtr = TokenAfter(tokenPtr);
+ return status;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * GetIntegerOperand --
+ *
+ * Retrieves an integer operand from the input stream and advances the
+ * token pointer.
+ *
+ * Results:
+ * Returns a standard Tcl result (with an error message in the
+ * interpreter on failure).
+ *
+ * Side effects:
+ * Stores the integer value in (*result) and advances (*tokenPtrPtr) to
+ * the next token.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static int
+GetIntegerOperand(
+ AssemblyEnv* assemEnvPtr, /* Assembly environment */
+ Tcl_Token** tokenPtrPtr, /* Current token from the parser */
+ int* result) /* OUTPUT: Integer extracted from the token */
+{
+ CompileEnv* envPtr = assemEnvPtr->envPtr;
+ /* Compilation environment */
+ Tcl_Interp* interp = (Tcl_Interp*) envPtr->iPtr;
+ /* Tcl interpreter */
+ Tcl_Token* tokenPtr = *tokenPtrPtr;
+ /* INOUT: Pointer to the next token in the
+ * source code */
+ Tcl_Obj* intObj; /* Integer from the source code */
+ int status; /* Tcl status return */
+
+ /*
+ * Extract the next token as a string.
+ */
+
+ if (GetNextOperand(assemEnvPtr, tokenPtrPtr, &intObj) != TCL_OK) {
+ return TCL_ERROR;
+ }
+
+ /*
+ * Convert to an integer, advance to the next token and return.
+ */
+
+ status = Tcl_GetIntFromObj(interp, intObj, result);
+ Tcl_DecrRefCount(intObj);
+ *tokenPtrPtr = TokenAfter(tokenPtr);
+ return status;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * GetListIndexOperand --
+ *
+ * Gets the value of an operand intended to serve as a list index.
+ *
+ * Results:
+ * Returns a standard Tcl result: TCL_OK if the parse is successful and
+ * TCL_ERROR (with an appropriate error message) if the parse fails.
+ *
+ * Side effects:
+ * Stores the list index at '*index'. Values between -1 and 0x7FFFFFFF
+ * have their natural meaning; values between -2 and -0x80000000
+ * represent 'end-2-N'.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static int
+GetListIndexOperand(
+ AssemblyEnv* assemEnvPtr, /* Assembly environment */
+ Tcl_Token** tokenPtrPtr, /* Current token from the parser */
+ int* result) /* OUTPUT: Integer extracted from the token */
+{
+ CompileEnv* envPtr = assemEnvPtr->envPtr;
+ /* Compilation environment */
+ Tcl_Interp* interp = (Tcl_Interp*) envPtr->iPtr;
+ /* Tcl interpreter */
+ Tcl_Token* tokenPtr = *tokenPtrPtr;
+ /* INOUT: Pointer to the next token in the
+ * source code */
+ Tcl_Obj *value;
+ int status;
+
+ /* General operand validity check */
+ if (GetNextOperand(assemEnvPtr, tokenPtrPtr, &value) != TCL_OK) {
+ return TCL_ERROR;
+ }
+
+ /* Convert to an integer, advance to the next token and return. */
+ /*
+ * NOTE: Indexing a list with an index before it yields the
+ * same result as indexing after it, and might be more easily portable
+ * when list size limits grow.
+ */
+ status = TclIndexEncode(interp, value,
+ TCL_INDEX_BEFORE,TCL_INDEX_BEFORE, result);
+
+ Tcl_DecrRefCount(value);
+ *tokenPtrPtr = TokenAfter(tokenPtr);
+ return status;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * FindLocalVar --
+ *
+ * Gets the name of a local variable from the input stream and advances
+ * the token pointer.
+ *
+ * Results:
+ * Returns the LVT index of the local variable. Returns -1 if the
+ * variable is non-local, not known at compile time, or cannot be
+ * installed in the LVT (leaving an error message in the interpreter
+ * result if necessary).
+ *
+ * Side effects:
+ * Advances the token pointer. May define a new LVT slot if the variable
+ * has not yet been seen and the execution context allows for it.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static int
+FindLocalVar(
+ AssemblyEnv* assemEnvPtr, /* Assembly environment */
+ Tcl_Token** tokenPtrPtr)
+{
+ CompileEnv* envPtr = assemEnvPtr->envPtr;
+ /* Compilation environment */
+ Tcl_Interp* interp = (Tcl_Interp*) envPtr->iPtr;
+ /* Tcl interpreter */
+ Tcl_Token* tokenPtr = *tokenPtrPtr;
+ /* INOUT: Pointer to the next token in the
+ * source code. */
+ Tcl_Obj* varNameObj; /* Name of the variable */
+ const char* varNameStr;
+ int varNameLen;
+ int localVar; /* Index of the variable in the LVT */
+
+ if (GetNextOperand(assemEnvPtr, tokenPtrPtr, &varNameObj) != TCL_OK) {
+ return -1;
+ }
+ varNameStr = Tcl_GetStringFromObj(varNameObj, &varNameLen);
+ if (CheckNamespaceQualifiers(interp, varNameStr, varNameLen)) {
+ Tcl_DecrRefCount(varNameObj);
+ return -1;
+ }
+ localVar = TclFindCompiledLocal(varNameStr, varNameLen, 1, envPtr);
+ Tcl_DecrRefCount(varNameObj);
+ if (localVar == -1) {
+ if (assemEnvPtr->flags & TCL_EVAL_DIRECT) {
+ Tcl_SetObjResult(interp, Tcl_NewStringObj(
+ "cannot use this instruction to create a variable"
+ " in a non-proc context", -1));
+ Tcl_SetErrorCode(interp, "TCL", "ASSEM", "LVT", NULL);
+ }
+ return -1;
+ }
+ *tokenPtrPtr = TokenAfter(tokenPtr);
+ return localVar;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * CheckNamespaceQualifiers --
+ *
+ * Verify that a variable name has no namespace qualifiers before
+ * attempting to install it in the LVT.
+ *
+ * Results:
+ * On success, returns TCL_OK. On failure, returns TCL_ERROR and stores
+ * an error message in the interpreter result.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static int
+CheckNamespaceQualifiers(
+ Tcl_Interp* interp, /* Tcl interpreter for error reporting */
+ const char* name, /* Variable name to check */
+ int nameLen) /* Length of the variable */
+{
+ const char* p;
+
+ for (p = name; p+2 < name+nameLen; p++) {
+ if ((*p == ':') && (p[1] == ':')) {
+ Tcl_SetObjResult(interp, Tcl_ObjPrintf(
+ "variable \"%s\" is not local", name));
+ Tcl_SetErrorCode(interp, "TCL", "ASSEM", "NONLOCAL", name, NULL);
+ return TCL_ERROR;
+ }
+ }
+ return TCL_OK;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * CheckOneByte --
+ *
+ * Verify that a constant fits in a single byte in the instruction
+ * stream.
+ *
+ * Results:
+ * On success, returns TCL_OK. On failure, returns TCL_ERROR and stores
+ * an error message in the interpreter result.
+ *
+ * This code is here primarily to verify that instructions like INCR_SCALAR1
+ * are possible on a given local variable. The fact that there is no
+ * INCR_SCALAR4 is puzzling.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static int
+CheckOneByte(
+ Tcl_Interp* interp, /* Tcl interpreter for error reporting */
+ int value) /* Value to check */
+{
+ Tcl_Obj* result; /* Error message */
+
+ if (value < 0 || value > 0xFF) {
+ result = Tcl_NewStringObj("operand does not fit in one byte", -1);
+ Tcl_SetObjResult(interp, result);
+ Tcl_SetErrorCode(interp, "TCL", "ASSEM", "1BYTE", NULL);
+ return TCL_ERROR;
+ }
+ return TCL_OK;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * CheckSignedOneByte --
+ *
+ * Verify that a constant fits in a single signed byte in the instruction
+ * stream.
+ *
+ * Results:
+ * On success, returns TCL_OK. On failure, returns TCL_ERROR and stores
+ * an error message in the interpreter result.
+ *
+ * This code is here primarily to verify that instructions like INCR_SCALAR1
+ * are possible on a given local variable. The fact that there is no
+ * INCR_SCALAR4 is puzzling.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static int
+CheckSignedOneByte(
+ Tcl_Interp* interp, /* Tcl interpreter for error reporting */
+ int value) /* Value to check */
+{
+ Tcl_Obj* result; /* Error message */
+
+ if (value > 0x7F || value < -0x80) {
+ result = Tcl_NewStringObj("operand does not fit in one byte", -1);
+ Tcl_SetObjResult(interp, result);
+ Tcl_SetErrorCode(interp, "TCL", "ASSEM", "1BYTE", NULL);
+ return TCL_ERROR;
+ }
+ return TCL_OK;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * CheckNonNegative --
+ *
+ * Verify that a constant is nonnegative
+ *
+ * Results:
+ * On success, returns TCL_OK. On failure, returns TCL_ERROR and stores
+ * an error message in the interpreter result.
+ *
+ * This code is here primarily to verify that instructions like INCR_INVOKE
+ * are consuming a positive number of operands
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static int
+CheckNonNegative(
+ Tcl_Interp* interp, /* Tcl interpreter for error reporting */
+ int value) /* Value to check */
+{
+ Tcl_Obj* result; /* Error message */
+
+ if (value < 0) {
+ result = Tcl_NewStringObj("operand must be nonnegative", -1);
+ Tcl_SetObjResult(interp, result);
+ Tcl_SetErrorCode(interp, "TCL", "ASSEM", "NONNEGATIVE", NULL);
+ return TCL_ERROR;
+ }
+ return TCL_OK;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * CheckStrictlyPositive --
+ *
+ * Verify that a constant is positive
+ *
+ * Results:
+ * On success, returns TCL_OK. On failure, returns TCL_ERROR and
+ * stores an error message in the interpreter result.
+ *
+ * This code is here primarily to verify that instructions like INCR_INVOKE
+ * are consuming a positive number of operands
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static int
+CheckStrictlyPositive(
+ Tcl_Interp* interp, /* Tcl interpreter for error reporting */
+ int value) /* Value to check */
+{
+ Tcl_Obj* result; /* Error message */
+
+ if (value <= 0) {
+ result = Tcl_NewStringObj("operand must be positive", -1);
+ Tcl_SetObjResult(interp, result);
+ Tcl_SetErrorCode(interp, "TCL", "ASSEM", "POSITIVE", NULL);
+ return TCL_ERROR;
+ }
+ return TCL_OK;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * DefineLabel --
+ *
+ * Defines a label appearing in the assembly sequence.
+ *
+ * Results:
+ * Returns a standard Tcl result. Returns TCL_OK and an empty result if
+ * the definition succeeds; returns TCL_ERROR and an appropriate message
+ * if a duplicate definition is found.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static int
+DefineLabel(
+ AssemblyEnv* assemEnvPtr, /* Assembly environment */
+ const char* labelName) /* Label being defined */
+{
+ CompileEnv* envPtr = assemEnvPtr->envPtr;
+ /* Compilation environment */
+ Tcl_Interp* interp = (Tcl_Interp*) envPtr->iPtr;
+ /* Tcl interpreter */
+ Tcl_HashEntry* entry; /* Label's entry in the symbol table */
+ int isNew; /* Flag == 1 iff the label was previously
+ * undefined */
+
+ /* TODO - This can now be simplified! */
+
+ StartBasicBlock(assemEnvPtr, BB_FALLTHRU, NULL);
+
+ /*
+ * Look up the newly-defined label in the symbol table.
+ */
+
+ entry = Tcl_CreateHashEntry(&assemEnvPtr->labelHash, labelName, &isNew);
+ if (!isNew) {
+ /*
+ * This is a duplicate label.
+ */
+
+ if (assemEnvPtr->flags & TCL_EVAL_DIRECT) {
+ Tcl_SetObjResult(interp, Tcl_ObjPrintf(
+ "duplicate definition of label \"%s\"", labelName));
+ Tcl_SetErrorCode(interp, "TCL", "ASSEM", "DUPLABEL", labelName,
+ NULL);
+ }
+ return TCL_ERROR;
+ }
+
+ /*
+ * This is the first appearance of the label in the code.
+ */
+
+ Tcl_SetHashValue(entry, assemEnvPtr->curr_bb);
+ return TCL_OK;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * StartBasicBlock --
+ *
+ * Starts a new basic block when a label or jump is encountered.
+ *
+ * Results:
+ * Returns a pointer to the BasicBlock structure of the new
+ * basic block.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static BasicBlock*
+StartBasicBlock(
+ AssemblyEnv* assemEnvPtr, /* Assembly environment */
+ int flags, /* Flags to apply to the basic block being
+ * closed, if there is one. */
+ Tcl_Obj* jumpLabel) /* Label of the location that the block jumps
+ * to, or NULL if the block does not jump */
+{
+ CompileEnv* envPtr = assemEnvPtr->envPtr;
+ /* Compilation environment */
+ BasicBlock* newBB; /* BasicBlock structure for the new block */
+ BasicBlock* currBB = assemEnvPtr->curr_bb;
+
+ /*
+ * Coalesce zero-length blocks.
+ */
+
+ if (currBB->startOffset == envPtr->codeNext - envPtr->codeStart) {
+ currBB->startLine = assemEnvPtr->cmdLine;
+ return currBB;
+ }
+
+ /*
+ * Make the new basic block.
+ */
+
+ newBB = AllocBB(assemEnvPtr);
+
+ /*
+ * Record the jump target if there is one.
+ */
+
+ currBB->jumpTarget = jumpLabel;
+ if (jumpLabel != NULL) {
+ Tcl_IncrRefCount(currBB->jumpTarget);
+ }
+
+ /*
+ * Record the fallthrough if there is one.
+ */
+
+ currBB->flags |= flags;
+
+ /*
+ * Record the successor block.
+ */
+
+ currBB->successor1 = newBB;
+ assemEnvPtr->curr_bb = newBB;
+ return newBB;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * AllocBB --
+ *
+ * Allocates a new basic block
+ *
+ * Results:
+ * Returns a pointer to the newly allocated block, which is initialized
+ * to contain no code and begin at the current instruction pointer.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static BasicBlock *
+AllocBB(
+ AssemblyEnv* assemEnvPtr) /* Assembly environment */
+{
+ CompileEnv* envPtr = assemEnvPtr->envPtr;
+ BasicBlock *bb = (BasicBlock*)ckalloc(sizeof(BasicBlock));
+
+ bb->originalStartOffset =
+ bb->startOffset = envPtr->codeNext - envPtr->codeStart;
+ bb->startLine = assemEnvPtr->cmdLine + 1;
+ bb->jumpOffset = -1;
+ bb->jumpLine = -1;
+ bb->prevPtr = assemEnvPtr->curr_bb;
+ bb->predecessor = NULL;
+ bb->successor1 = NULL;
+ bb->jumpTarget = NULL;
+ bb->initialStackDepth = 0;
+ bb->minStackDepth = 0;
+ bb->maxStackDepth = 0;
+ bb->finalStackDepth = 0;
+ bb->catchDepth = 0;
+ bb->enclosingCatch = NULL;
+ bb->foreignExceptionBase = -1;
+ bb->foreignExceptionCount = 0;
+ bb->foreignExceptions = NULL;
+ bb->jtPtr = NULL;
+ bb->flags = 0;
+
+ return bb;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * FinishAssembly --
+ *
+ * Postprocessing after all bytecode has been generated for a block of
+ * assembly code.
+ *
+ * Results:
+ * Returns a standard Tcl result, with an error message left in the
+ * interpreter if appropriate.
+ *
+ * Side effects:
+ * The program is checked to see if any undefined labels remain. The
+ * initial stack depth of all the basic blocks in the flow graph is
+ * calculated and saved. The stack balance on exit is computed, checked
+ * and saved.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static int
+FinishAssembly(
+ AssemblyEnv* assemEnvPtr) /* Assembly environment */
+{
+ int mustMove; /* Amount by which the code needs to be grown
+ * because of expanding jumps */
+
+ /*
+ * Resolve the targets of all jumps and determine whether code needs to be
+ * moved around.
+ */
+
+ if (CalculateJumpRelocations(assemEnvPtr, &mustMove)) {
+ return TCL_ERROR;
+ }
+
+ /*
+ * Move the code if necessary.
+ */
+
+ if (mustMove) {
+ MoveCodeForJumps(assemEnvPtr, mustMove);
+ }
+
+ /*
+ * Resolve jump target labels to bytecode offsets.
+ */
+
+ FillInJumpOffsets(assemEnvPtr);
+
+ /*
+ * Label each basic block with its catch context. Quit on inconsistency.
+ */
+
+ if (ProcessCatches(assemEnvPtr) != TCL_OK) {
+ return TCL_ERROR;
+ }
+
+ /*
+ * Make sure that no block accessible from a catch's error exit that hasn't
+ * popped the exception stack can throw an exception.
+ */
+
+ if (CheckForThrowInWrongContext(assemEnvPtr) != TCL_OK) {
+ return TCL_ERROR;
+ }
+
+ /*
+ * Compute stack balance throughout the program.
+ */
+
+ if (CheckStack(assemEnvPtr) != TCL_OK) {
+ return TCL_ERROR;
+ }
+
+ /*
+ * TODO - Check for unreachable code. Or maybe not; unreachable code is
+ * Mostly Harmless.
+ */
+
+ return TCL_OK;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * CalculateJumpRelocations --
+ *
+ * Calculate any movement that has to be done in the assembly code to
+ * expand JUMP1 instructions to JUMP4 (because they jump more than a
+ * 1-byte range).
+ *
+ * Results:
+ * Returns a standard Tcl result, with an appropriate error message if
+ * anything fails.
+ *
+ * Side effects:
+ * Sets the 'startOffset' pointer in every basic block to the new origin
+ * of the block, and turns off JUMP1 flags on instructions that must be
+ * expanded (and adjusts them to the corresponding JUMP4's). Does *not*
+ * store the jump offsets at this point.
+ *
+ * Sets *mustMove to 1 if and only if at least one instruction changed
+ * size so the code must be moved.
+ *
+ * As a side effect, also checks for undefined labels and reports them.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static int
+CalculateJumpRelocations(
+ AssemblyEnv* assemEnvPtr, /* Assembly environment */
+ int* mustMove) /* OUTPUT: Number of bytes that have been
+ * added to the code */
+{
+ CompileEnv* envPtr = assemEnvPtr->envPtr;
+ /* Compilation environment */
+ BasicBlock* bbPtr; /* Pointer to a basic block being checked */
+ Tcl_HashEntry* entry; /* Exit label's entry in the symbol table */
+ BasicBlock* jumpTarget; /* Basic block where the jump goes */
+ int motion; /* Amount by which the code has expanded */
+ int offset; /* Offset in the bytecode from a jump
+ * instruction to its target */
+ unsigned opcode; /* Opcode in the bytecode being adjusted */
+
+ /*
+ * Iterate through basic blocks as long as a change results in code
+ * expansion.
+ */
+
+ *mustMove = 0;
+ do {
+ motion = 0;
+ for (bbPtr = assemEnvPtr->head_bb;
+ bbPtr != NULL;
+ bbPtr = bbPtr->successor1) {
+ /*
+ * Advance the basic block start offset by however many bytes we
+ * have inserted in the code up to this point
+ */
+
+ bbPtr->startOffset += motion;
+
+ /*
+ * If the basic block references a label (and hence performs a
+ * jump), find the location of the label. Report an error if the
+ * label is missing.
+ */
+
+ if (bbPtr->jumpTarget != NULL) {
+ entry = Tcl_FindHashEntry(&assemEnvPtr->labelHash,
+ Tcl_GetString(bbPtr->jumpTarget));
+ if (entry == NULL) {
+ ReportUndefinedLabel(assemEnvPtr, bbPtr,
+ bbPtr->jumpTarget);
+ return TCL_ERROR;
+ }
+
+ /*
+ * If the instruction is a JUMP1, turn it into a JUMP4 if its
+ * target is out of range.
+ */
+
+ jumpTarget = (BasicBlock*)Tcl_GetHashValue(entry);
+ if (bbPtr->flags & BB_JUMP1) {
+ offset = jumpTarget->startOffset
+ - (bbPtr->jumpOffset + motion);
+ if (offset < -0x80 || offset > 0x7F) {
+ opcode = TclGetUInt1AtPtr(envPtr->codeStart
+ + bbPtr->jumpOffset);
+ ++opcode;
+ TclStoreInt1AtPtr(opcode,
+ envPtr->codeStart + bbPtr->jumpOffset);
+ motion += 3;
+ bbPtr->flags &= ~BB_JUMP1;
+ }
+ }
+ }
+
+ /*
+ * If the basic block references a jump table, that doesn't affect
+ * the code locations, but resolve the labels now, and store basic
+ * block pointers in the jumptable hash.
+ */
+
+ if (bbPtr->flags & BB_JUMPTABLE) {
+ if (CheckJumpTableLabels(assemEnvPtr, bbPtr) != TCL_OK) {
+ return TCL_ERROR;
+ }
+ }
+ }
+ *mustMove += motion;
+ } while (motion != 0);
+
+ return TCL_OK;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * CheckJumpTableLabels --
+ *
+ * Make sure that all the labels in a jump table are defined.
+ *
+ * Results:
+ * Returns TCL_OK if they are, TCL_ERROR if they aren't.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static int
+CheckJumpTableLabels(
+ AssemblyEnv* assemEnvPtr, /* Assembly environment */
+ BasicBlock* bbPtr) /* Basic block that ends in a jump table */
+{
+ Tcl_HashTable* symHash = &bbPtr->jtPtr->hashTable;
+ /* Hash table with the symbols */
+ Tcl_HashSearch search; /* Hash table iterator */
+ Tcl_HashEntry* symEntryPtr; /* Hash entry for the symbols */
+ Tcl_Obj* symbolObj; /* Jump target */
+ Tcl_HashEntry* valEntryPtr; /* Hash entry for the resolutions */
+
+ /*
+ * Look up every jump target in the jump hash.
+ */
+
+ DEBUG_PRINT("check jump table labels %p {\n", bbPtr);
+ for (symEntryPtr = Tcl_FirstHashEntry(symHash, &search);
+ symEntryPtr != NULL;
+ symEntryPtr = Tcl_NextHashEntry(&search)) {
+ symbolObj = (Tcl_Obj*)Tcl_GetHashValue(symEntryPtr);
+ valEntryPtr = Tcl_FindHashEntry(&assemEnvPtr->labelHash,
+ Tcl_GetString(symbolObj));
+ DEBUG_PRINT(" %s -> %s (%d)\n",
+ (char*) Tcl_GetHashKey(symHash, symEntryPtr),
+ Tcl_GetString(symbolObj), (valEntryPtr != NULL));
+ if (valEntryPtr == NULL) {
+ ReportUndefinedLabel(assemEnvPtr, bbPtr, symbolObj);
+ return TCL_ERROR;
+ }
+ }
+ DEBUG_PRINT("}\n");
+ return TCL_OK;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * ReportUndefinedLabel --
+ *
+ * Report that a basic block refers to an undefined jump label
+ *
+ * Side effects:
+ * Stores an error message, error code, and line number information in
+ * the assembler's Tcl interpreter.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static void
+ReportUndefinedLabel(
+ AssemblyEnv* assemEnvPtr, /* Assembly environment */
+ BasicBlock* bbPtr, /* Basic block that contains the undefined
+ * label */
+ Tcl_Obj* jumpTarget) /* Label of a jump target */
+{
+ CompileEnv* envPtr = assemEnvPtr->envPtr;
+ /* Compilation environment */
+ Tcl_Interp* interp = (Tcl_Interp*) envPtr->iPtr;
+ /* Tcl interpreter */
+
+ if (assemEnvPtr->flags & TCL_EVAL_DIRECT) {
+ Tcl_SetObjResult(interp, Tcl_ObjPrintf(
+ "undefined label \"%s\"", Tcl_GetString(jumpTarget)));
+ Tcl_SetErrorCode(interp, "TCL", "ASSEM", "NOLABEL",
+ Tcl_GetString(jumpTarget), NULL);
+ Tcl_SetErrorLine(interp, bbPtr->jumpLine);
+ }
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * MoveCodeForJumps --
+ *
+ * Move bytecodes in memory to accommodate JUMP1 instructions that have
+ * expanded to become JUMP4's.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static void
+MoveCodeForJumps(
+ AssemblyEnv* assemEnvPtr, /* Assembler environment */
+ int mustMove) /* Number of bytes of added code */
+{
+ CompileEnv* envPtr = assemEnvPtr->envPtr;
+ /* Compilation environment */
+ BasicBlock* bbPtr; /* Pointer to a basic block being checked */
+ int topOffset; /* Bytecode offset of the following basic
+ * block before code motion */
+
+ /*
+ * Make sure that there is enough space in the bytecode array to
+ * accommodate the expanded code.
+ */
+
+ while (envPtr->codeEnd < envPtr->codeNext + mustMove) {
+ TclExpandCodeArray(envPtr);
+ }
+
+ /*
+ * Iterate through the bytecodes in reverse order, and move them upward to
+ * their new homes.
+ */
+
+ topOffset = envPtr->codeNext - envPtr->codeStart;
+ for (bbPtr = assemEnvPtr->curr_bb; bbPtr != NULL; bbPtr = bbPtr->prevPtr) {
+ DEBUG_PRINT("move code from %d to %d\n",
+ bbPtr->originalStartOffset, bbPtr->startOffset);
+ memmove(envPtr->codeStart + bbPtr->startOffset,
+ envPtr->codeStart + bbPtr->originalStartOffset,
+ topOffset - bbPtr->originalStartOffset);
+ topOffset = bbPtr->originalStartOffset;
+ bbPtr->jumpOffset += (bbPtr->startOffset - bbPtr->originalStartOffset);
+ }
+ envPtr->codeNext += mustMove;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * FillInJumpOffsets --
+ *
+ * Fill in the final offsets of all jump instructions once bytecode
+ * locations have been completely determined.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static void
+FillInJumpOffsets(
+ AssemblyEnv* assemEnvPtr) /* Assembly environment */
+{
+ CompileEnv* envPtr = assemEnvPtr->envPtr;
+ /* Compilation environment */
+ BasicBlock* bbPtr; /* Pointer to a basic block being checked */
+ Tcl_HashEntry* entry; /* Hashtable entry for a jump target label */
+ BasicBlock* jumpTarget; /* Basic block where a jump goes */
+ int fromOffset; /* Bytecode location of a jump instruction */
+ int targetOffset; /* Bytecode location of a jump instruction's
+ * target */
+
+ for (bbPtr = assemEnvPtr->head_bb;
+ bbPtr != NULL;
+ bbPtr = bbPtr->successor1) {
+ if (bbPtr->jumpTarget != NULL) {
+ entry = Tcl_FindHashEntry(&assemEnvPtr->labelHash,
+ Tcl_GetString(bbPtr->jumpTarget));
+ jumpTarget = (BasicBlock*)Tcl_GetHashValue(entry);
+ fromOffset = bbPtr->jumpOffset;
+ targetOffset = jumpTarget->startOffset;
+ if (bbPtr->flags & BB_JUMP1) {
+ TclStoreInt1AtPtr(targetOffset - fromOffset,
+ envPtr->codeStart + fromOffset + 1);
+ } else {
+ TclStoreInt4AtPtr(targetOffset - fromOffset,
+ envPtr->codeStart + fromOffset + 1);
+ }
+ }
+ if (bbPtr->flags & BB_JUMPTABLE) {
+ ResolveJumpTableTargets(assemEnvPtr, bbPtr);
+ }
+ }
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * ResolveJumpTableTargets --
+ *
+ * Puts bytecode addresses for the targets of a jumptable into the
+ * table
+ *
+ * Results:
+ * Returns TCL_OK if they are, TCL_ERROR if they aren't.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static void
+ResolveJumpTableTargets(
+ AssemblyEnv* assemEnvPtr, /* Assembly environment */
+ BasicBlock* bbPtr) /* Basic block that ends in a jump table */
+{
+ CompileEnv* envPtr = assemEnvPtr->envPtr;
+ /* Compilation environment */
+ Tcl_HashTable* symHash = &bbPtr->jtPtr->hashTable;
+ /* Hash table with the symbols */
+ Tcl_HashSearch search; /* Hash table iterator */
+ Tcl_HashEntry* symEntryPtr; /* Hash entry for the symbols */
+ Tcl_Obj* symbolObj; /* Jump target */
+ Tcl_HashEntry* valEntryPtr; /* Hash entry for the resolutions */
+ int auxDataIndex; /* Index of the auxdata */
+ JumptableInfo* realJumpTablePtr;
+ /* Jump table in the actual code */
+ Tcl_HashTable* realJumpHashPtr;
+ /* Jump table hash in the actual code */
+ Tcl_HashEntry* realJumpEntryPtr;
+ /* Entry in the jump table hash in
+ * the actual code */
+ BasicBlock* jumpTargetBBPtr;
+ /* Basic block that the jump proceeds to */
+ int junk;
+
+ auxDataIndex = TclGetInt4AtPtr(envPtr->codeStart + bbPtr->jumpOffset + 1);
+ DEBUG_PRINT("bbPtr = %p jumpOffset = %d auxDataIndex = %d\n",
+ bbPtr, bbPtr->jumpOffset, auxDataIndex);
+ realJumpTablePtr = (JumptableInfo*)TclFetchAuxData(envPtr, auxDataIndex);
+ realJumpHashPtr = &realJumpTablePtr->hashTable;
+
+ /*
+ * Look up every jump target in the jump hash.
+ */
+
+ DEBUG_PRINT("resolve jump table {\n");
+ for (symEntryPtr = Tcl_FirstHashEntry(symHash, &search);
+ symEntryPtr != NULL;
+ symEntryPtr = Tcl_NextHashEntry(&search)) {
+ symbolObj = (Tcl_Obj*)Tcl_GetHashValue(symEntryPtr);
+ DEBUG_PRINT(" symbol %s\n", Tcl_GetString(symbolObj));
+
+ valEntryPtr = Tcl_FindHashEntry(&assemEnvPtr->labelHash,
+ Tcl_GetString(symbolObj));
+ jumpTargetBBPtr = (BasicBlock*)Tcl_GetHashValue(valEntryPtr);
+
+ realJumpEntryPtr = Tcl_CreateHashEntry(realJumpHashPtr,
+ Tcl_GetHashKey(symHash, symEntryPtr), &junk);
+ DEBUG_PRINT(" %s -> %s -> bb %p (pc %d) hash entry %p\n",
+ (char*) Tcl_GetHashKey(symHash, symEntryPtr),
+ Tcl_GetString(symbolObj), jumpTargetBBPtr,
+ jumpTargetBBPtr->startOffset, realJumpEntryPtr);
+
+ Tcl_SetHashValue(realJumpEntryPtr,
+ INT2PTR(jumpTargetBBPtr->startOffset - bbPtr->jumpOffset));
+ }
+ DEBUG_PRINT("}\n");
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * CheckForThrowInWrongContext --
+ *
+ * Verify that no beginCatch/endCatch sequence can throw an exception
+ * after an original exception is caught and before its exception context
+ * is removed from the stack.
+ *
+ * Results:
+ * Returns a standard Tcl result.
+ *
+ * Side effects:
+ * Stores an appropriate error message in the interpreter as needed.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static int
+CheckForThrowInWrongContext(
+ AssemblyEnv* assemEnvPtr) /* Assembly environment */
+{
+ BasicBlock* blockPtr; /* Current basic block */
+
+ /*
+ * Walk through the basic blocks in turn, checking all the ones that have
+ * caught an exception and not disposed of it properly.
+ */
+
+ for (blockPtr = assemEnvPtr->head_bb;
+ blockPtr != NULL;
+ blockPtr = blockPtr->successor1) {
+ if (blockPtr->catchState == BBCS_CAUGHT) {
+ /*
+ * Walk through the instructions in the basic block.
+ */
+
+ if (CheckNonThrowingBlock(assemEnvPtr, blockPtr) != TCL_OK) {
+ return TCL_ERROR;
+ }
+ }
+ }
+ return TCL_OK;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * CheckNonThrowingBlock --
+ *
+ * Check that a basic block cannot throw an exception.
+ *
+ * Results:
+ * Returns TCL_ERROR if the block cannot be proven to be nonthrowing.
+ *
+ * Side effects:
+ * Stashes an error message in the interpreter result.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static int
+CheckNonThrowingBlock(
+ AssemblyEnv* assemEnvPtr, /* Assembly environment */
+ BasicBlock* blockPtr) /* Basic block where exceptions are not
+ * allowed */
+{
+ CompileEnv* envPtr = assemEnvPtr->envPtr;
+ /* Compilation environment */
+ Tcl_Interp* interp = (Tcl_Interp*) envPtr->iPtr;
+ /* Tcl interpreter */
+ BasicBlock* nextPtr; /* Pointer to the succeeding basic block */
+ int offset; /* Bytecode offset of the current
+ * instruction */
+ int bound; /* Bytecode offset following the last
+ * instruction of the block. */
+ unsigned char opcode; /* Current bytecode instruction */
+
+ /*
+ * Determine where in the code array the basic block ends.
+ */
+
+ nextPtr = blockPtr->successor1;
+ if (nextPtr == NULL) {
+ bound = envPtr->codeNext - envPtr->codeStart;
+ } else {
+ bound = nextPtr->startOffset;
+ }
+
+ /*
+ * Walk through the instructions of the block.
+ */
+
+ offset = blockPtr->startOffset;
+ while (offset < bound) {
+ /*
+ * Determine whether an instruction is nonthrowing.
+ */
+
+ opcode = (envPtr->codeStart)[offset];
+ if (BytecodeMightThrow(opcode)) {
+ /*
+ * Report an error for a throw in the wrong context.
+ */
+
+ if (assemEnvPtr->flags & TCL_EVAL_DIRECT) {
+ Tcl_SetObjResult(interp, Tcl_ObjPrintf(
+ "\"%s\" instruction may not appear in "
+ "a context where an exception has been "
+ "caught and not disposed of.",
+ tclInstructionTable[opcode].name));
+ Tcl_SetErrorCode(interp, "TCL", "ASSEM", "BADTHROW", NULL);
+ AddBasicBlockRangeToErrorInfo(assemEnvPtr, blockPtr);
+ }
+ return TCL_ERROR;
+ }
+ offset += tclInstructionTable[opcode].numBytes;
+ }
+ return TCL_OK;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * BytecodeMightThrow --
+ *
+ * Tests if a given bytecode instruction might throw an exception.
+ *
+ * Results:
+ * Returns 1 if the bytecode might throw an exception, 0 if the
+ * instruction is known never to throw.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static int
+BytecodeMightThrow(
+ unsigned char opcode)
+{
+ /*
+ * Binary search on the non-throwing bytecode list.
+ */
+
+ int min = 0;
+ int max = sizeof(NonThrowingByteCodes) - 1;
+ int mid;
+ unsigned char c;
+
+ while (max >= min) {
+ mid = (min + max) / 2;
+ c = NonThrowingByteCodes[mid];
+ if (opcode < c) {
+ max = mid-1;
+ } else if (opcode > c) {
+ min = mid+1;
+ } else {
+ /*
+ * Opcode is nonthrowing.
+ */
+
+ return 0;
+ }
+ }
+
+ return 1;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * CheckStack --
+ *
+ * Audit stack usage in a block of assembly code.
+ *
+ * Results:
+ * Returns a standard Tcl result.
+ *
+ * Side effects:
+ * Updates stack depth on entry for all basic blocks in the flowgraph.
+ * Calculates the max stack depth used in the program, and updates the
+ * compilation environment to reflect it.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static int
+CheckStack(
+ AssemblyEnv* assemEnvPtr) /* Assembly environment */
+{
+ CompileEnv* envPtr = assemEnvPtr->envPtr;
+ /* Compilation environment */
+ int maxDepth; /* Maximum stack depth overall */
+
+ /*
+ * Checking the head block will check all the other blocks recursively.
+ */
+
+ assemEnvPtr->maxDepth = 0;
+ if (StackCheckBasicBlock(assemEnvPtr, assemEnvPtr->head_bb, NULL,
+ 0) == TCL_ERROR) {
+ return TCL_ERROR;
+ }
+
+ /*
+ * Post the max stack depth back to the compilation environment.
+ */
+
+ maxDepth = assemEnvPtr->maxDepth + envPtr->currStackDepth;
+ if (maxDepth > envPtr->maxStackDepth) {
+ envPtr->maxStackDepth = maxDepth;
+ }
+
+ /*
+ * If the exit is reachable, make sure that the program exits with 1
+ * operand on the stack.
+ */
+
+ if (StackCheckExit(assemEnvPtr) != TCL_OK) {
+ return TCL_ERROR;
+ }
+
+ /*
+ * Reset the visited state on all basic blocks.
+ */
+
+ ResetVisitedBasicBlocks(assemEnvPtr);
+ return TCL_OK;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * StackCheckBasicBlock --
+ *
+ * Checks stack consumption for a basic block (and recursively for its
+ * successors).
+ *
+ * Results:
+ * Returns a standard Tcl result.
+ *
+ * Side effects:
+ * Updates initial stack depth for the basic block and its successors.
+ * (Final and maximum stack depth are relative to initial, and are not
+ * touched).
+ *
+ * This procedure eventually checks, for the entire flow graph, whether stack
+ * balance is consistent. It is an error for a given basic block to be
+ * reachable along multiple flow paths with different stack depths.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static int
+StackCheckBasicBlock(
+ AssemblyEnv* assemEnvPtr, /* Assembly environment */
+ BasicBlock* blockPtr, /* Pointer to the basic block being checked */
+ BasicBlock* predecessor, /* Pointer to the block that passed control to
+ * this one. */
+ int initialStackDepth) /* Stack depth on entry to the block */
+{
+ CompileEnv* envPtr = assemEnvPtr->envPtr;
+ /* Compilation environment */
+ Tcl_Interp* interp = (Tcl_Interp*) envPtr->iPtr;
+ /* Tcl interpreter */
+ BasicBlock* jumpTarget; /* Basic block where a jump goes */
+ int stackDepth; /* Current stack depth */
+ int maxDepth; /* Maximum stack depth so far */
+ int result; /* Tcl status return */
+ Tcl_HashSearch jtSearch; /* Search structure for the jump table */
+ Tcl_HashEntry* jtEntry; /* Hash entry in the jump table */
+ Tcl_Obj* targetLabel; /* Target label from the jump table */
+ Tcl_HashEntry* entry; /* Hash entry in the label table */
+
+ if (blockPtr->flags & BB_VISITED) {
+ /*
+ * If the block is already visited, check stack depth for consistency
+ * among the paths that reach it.
+ */
+
+ if (blockPtr->initialStackDepth == initialStackDepth) {
+ return TCL_OK;
+ }
+ if (assemEnvPtr->flags & TCL_EVAL_DIRECT) {
+ Tcl_SetObjResult(interp, Tcl_NewStringObj(
+ "inconsistent stack depths on two execution paths", -1));
+
+ /*
+ * TODO - add execution trace of both paths
+ */
+
+ Tcl_SetErrorLine(interp, blockPtr->startLine);
+ Tcl_SetErrorCode(interp, "TCL", "ASSEM", "BADSTACK", NULL);
+ }
+ return TCL_ERROR;
+ }
+
+ /*
+ * If the block is not already visited, set the 'predecessor' link to
+ * indicate how control got to it. Set the initial stack depth to the
+ * current stack depth in the flow of control.
+ */
+
+ blockPtr->flags |= BB_VISITED;
+ blockPtr->predecessor = predecessor;
+ blockPtr->initialStackDepth = initialStackDepth;
+
+ /*
+ * Calculate minimum stack depth, and flag an error if the block
+ * underflows the stack.
+ */
+
+ if (initialStackDepth + blockPtr->minStackDepth < 0) {
+ if (assemEnvPtr->flags & TCL_EVAL_DIRECT) {
+ Tcl_SetObjResult(interp, Tcl_NewStringObj("stack underflow", -1));
+ Tcl_SetErrorCode(interp, "TCL", "ASSEM", "BADSTACK", NULL);
+ AddBasicBlockRangeToErrorInfo(assemEnvPtr, blockPtr);
+ Tcl_SetErrorLine(interp, blockPtr->startLine);
+ }
+ return TCL_ERROR;
+ }
+
+ /*
+ * Make sure that the block doesn't try to pop below the stack level of an
+ * enclosing catch.
+ */
+
+ if (blockPtr->enclosingCatch != 0 &&
+ initialStackDepth + blockPtr->minStackDepth
+ < (blockPtr->enclosingCatch->initialStackDepth
+ + blockPtr->enclosingCatch->finalStackDepth)) {
+ if (assemEnvPtr->flags & TCL_EVAL_DIRECT) {
+ Tcl_SetObjResult(interp, Tcl_NewStringObj(
+ "code pops stack below level of enclosing catch", -1));
+ Tcl_SetErrorCode(interp, "TCL", "ASSEM", "BADSTACKINCATCH", -1);
+ AddBasicBlockRangeToErrorInfo(assemEnvPtr, blockPtr);
+ Tcl_SetErrorLine(interp, blockPtr->startLine);
+ }
+ return TCL_ERROR;
+ }
+
+ /*
+ * Update maximum stgack depth.
+ */
+
+ maxDepth = initialStackDepth + blockPtr->maxStackDepth;
+ if (maxDepth > assemEnvPtr->maxDepth) {
+ assemEnvPtr->maxDepth = maxDepth;
+ }
+
+ /*
+ * Calculate stack depth on exit from the block, and invoke this procedure
+ * recursively to check successor blocks.
+ */
+
+ stackDepth = initialStackDepth + blockPtr->finalStackDepth;
+ result = TCL_OK;
+ if (blockPtr->flags & BB_FALLTHRU) {
+ result = StackCheckBasicBlock(assemEnvPtr, blockPtr->successor1,
+ blockPtr, stackDepth);
+ }
+
+ if (result == TCL_OK && blockPtr->jumpTarget != NULL) {
+ entry = Tcl_FindHashEntry(&assemEnvPtr->labelHash,
+ Tcl_GetString(blockPtr->jumpTarget));
+ jumpTarget = (BasicBlock*)Tcl_GetHashValue(entry);
+ result = StackCheckBasicBlock(assemEnvPtr, jumpTarget, blockPtr,
+ stackDepth);
+ }
+
+ /*
+ * All blocks referenced in a jump table are successors.
+ */
+
+ if (blockPtr->flags & BB_JUMPTABLE) {
+ for (jtEntry = Tcl_FirstHashEntry(&blockPtr->jtPtr->hashTable,
+ &jtSearch);
+ result == TCL_OK && jtEntry != NULL;
+ jtEntry = Tcl_NextHashEntry(&jtSearch)) {
+ targetLabel = (Tcl_Obj*)Tcl_GetHashValue(jtEntry);
+ entry = Tcl_FindHashEntry(&assemEnvPtr->labelHash,
+ Tcl_GetString(targetLabel));
+ jumpTarget = (BasicBlock*)Tcl_GetHashValue(entry);
+ result = StackCheckBasicBlock(assemEnvPtr, jumpTarget,
+ blockPtr, stackDepth);
+ }
+ }
+
+ return result;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * StackCheckExit --
+ *
+ * Makes sure that the net stack effect of an entire assembly language
+ * script is to push 1 result.
+ *
+ * Results:
+ * Returns a standard Tcl result, with an error message in the
+ * interpreter result if the stack is wrong.
+ *
+ * Side effects:
+ * If the assembly code had a net stack effect of zero, emits code to the
+ * concluding block to push a null result. In any case, updates the stack
+ * depth in the compile environment to reflect the net effect of the
+ * assembly code.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static int
+StackCheckExit(
+ AssemblyEnv* assemEnvPtr) /* Assembly environment */
+{
+ CompileEnv* envPtr = assemEnvPtr->envPtr;
+ /* Compilation environment */
+ Tcl_Interp* interp = (Tcl_Interp*) envPtr->iPtr;
+ /* Tcl interpreter */
+ int depth; /* Net stack effect */
+ int litIndex; /* Index in the literal pool of the empty
+ * string */
+ BasicBlock* curr_bb = assemEnvPtr->curr_bb;
+ /* Final basic block in the assembly */
+
+ /*
+ * Don't perform these checks if execution doesn't reach the exit (either
+ * because of an infinite loop or because the only return is from the
+ * middle.
+ */
+
+ if (curr_bb->flags & BB_VISITED) {
+ /*
+ * Exit with no operands; push an empty one.
+ */
+
+ depth = curr_bb->finalStackDepth + curr_bb->initialStackDepth;
+ if (depth == 0) {
+ /*
+ * Emit a 'push' of the empty literal.
+ */
+
+ litIndex = TclRegisterNewLiteral(envPtr, "", 0);
+
+ /*
+ * Assumes that 'push' is at slot 0 in TalInstructionTable.
+ */
+
+ BBEmitInst1or4(assemEnvPtr, 0, litIndex, 0);
+ ++depth;
+ }
+
+ /*
+ * Exit with unbalanced stack.
+ */
+
+ if (depth != 1) {
+ if (assemEnvPtr->flags & TCL_EVAL_DIRECT) {
+ Tcl_SetObjResult(interp, Tcl_ObjPrintf(
+ "stack is unbalanced on exit from the code (depth=%d)",
+ depth));
+ Tcl_SetErrorCode(interp, "TCL", "ASSEM", "BADSTACK", NULL);
+ }
+ return TCL_ERROR;
+ }
+
+ /*
+ * Record stack usage.
+ */
+
+ envPtr->currStackDepth += depth;
+ }
+
+ return TCL_OK;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * ProcessCatches --
+ *
+ * First pass of 'catch' processing.
+ *
+ * Results:
+ * Returns a standard Tcl result, with an appropriate error message if
+ * the result is TCL_ERROR.
+ *
+ * Side effects:
+ * Labels all basic blocks with their enclosing catches.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static int
+ProcessCatches(
+ AssemblyEnv* assemEnvPtr) /* Assembly environment */
+{
+ BasicBlock* blockPtr; /* Pointer to a basic block */
+
+ /*
+ * Clear the catch state of all basic blocks.
+ */
+
+ for (blockPtr = assemEnvPtr->head_bb;
+ blockPtr != NULL;
+ blockPtr = blockPtr->successor1) {
+ blockPtr->catchState = BBCS_UNKNOWN;
+ blockPtr->enclosingCatch = NULL;
+ }
+
+ /*
+ * Start the check recursively from the first basic block, which is
+ * outside any exception context
+ */
+
+ if (ProcessCatchesInBasicBlock(assemEnvPtr, assemEnvPtr->head_bb,
+ NULL, BBCS_NONE, 0) != TCL_OK) {
+ return TCL_ERROR;
+ }
+
+ /*
+ * Check for unclosed catch on exit.
+ */
+
+ if (CheckForUnclosedCatches(assemEnvPtr) != TCL_OK) {
+ return TCL_ERROR;
+ }
+
+ /*
+ * Now there's enough information to build the exception ranges.
+ */
+
+ if (BuildExceptionRanges(assemEnvPtr) != TCL_OK) {
+ return TCL_ERROR;
+ }
+
+ /*
+ * Finally, restore any exception ranges from embedded scripts.
+ */
+
+ RestoreEmbeddedExceptionRanges(assemEnvPtr);
+ return TCL_OK;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * ProcessCatchesInBasicBlock --
+ *
+ * First-pass catch processing for one basic block.
+ *
+ * Results:
+ * Returns a standard Tcl result, with error message in the interpreter
+ * result if an error occurs.
+ *
+ * This procedure checks consistency of the exception context through the
+ * assembler program, and records the enclosing 'catch' for every basic block.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static int
+ProcessCatchesInBasicBlock(
+ AssemblyEnv* assemEnvPtr, /* Assembly environment */
+ BasicBlock* bbPtr, /* Basic block being processed */
+ BasicBlock* enclosing, /* Start basic block of the enclosing catch */
+ enum BasicBlockCatchState state,
+ /* BBCS_NONE, BBCS_INCATCH, or BBCS_CAUGHT */
+ int catchDepth) /* Depth of nesting of catches */
+{
+ CompileEnv* envPtr = assemEnvPtr->envPtr;
+ /* Compilation environment */
+ Tcl_Interp* interp = (Tcl_Interp*) envPtr->iPtr;
+ /* Tcl interpreter */
+ int result; /* Return value from this procedure */
+ BasicBlock* fallThruEnclosing;
+ /* Enclosing catch if execution falls thru */
+ enum BasicBlockCatchState fallThruState;
+ /* Catch state of the successor block */
+ BasicBlock* jumpEnclosing; /* Enclosing catch if execution goes to jump
+ * target */
+ enum BasicBlockCatchState jumpState;
+ /* Catch state of the jump target */
+ int changed = 0; /* Flag == 1 iff successor blocks need to be
+ * checked because the state of this block has
+ * changed. */
+ BasicBlock* jumpTarget; /* Basic block where a jump goes */
+ Tcl_HashSearch jtSearch; /* Hash search control for a jumptable */
+ Tcl_HashEntry* jtEntry; /* Entry in a jumptable */
+ Tcl_Obj* targetLabel; /* Target label from a jumptable */
+ Tcl_HashEntry* entry; /* Entry from the label table */
+
+ /*
+ * Update the state of the current block, checking for consistency. Set
+ * 'changed' to 1 if the state changes and successor blocks need to be
+ * rechecked.
+ */
+
+ if (bbPtr->catchState == BBCS_UNKNOWN) {
+ bbPtr->enclosingCatch = enclosing;
+ } else if (bbPtr->enclosingCatch != enclosing) {
+ if (assemEnvPtr->flags & TCL_EVAL_DIRECT) {
+ Tcl_SetObjResult(interp, Tcl_NewStringObj(
+ "execution reaches an instruction in inconsistent "
+ "exception contexts", -1));
+ Tcl_SetErrorLine(interp, bbPtr->startLine);
+ Tcl_SetErrorCode(interp, "TCL", "ASSEM", "BADCATCH", NULL);
+ }
+ return TCL_ERROR;
+ }
+ if (state > bbPtr->catchState) {
+ bbPtr->catchState = state;
+ changed = 1;
+ }
+
+ /*
+ * If this block has been visited before, and its state hasn't changed,
+ * we're done with it for now.
+ */
+
+ if (!changed) {
+ return TCL_OK;
+ }
+ bbPtr->catchDepth = catchDepth;
+
+ /*
+ * Determine enclosing catch and 'caught' state for the fallthrough and
+ * the jump target. Default for both is the state of the current block.
+ */
+
+ fallThruEnclosing = enclosing;
+ fallThruState = state;
+ jumpEnclosing = enclosing;
+ jumpState = state;
+
+ /*
+ * TODO: Make sure that the test cases include validating that a natural
+ * loop can't include 'beginCatch' or 'endCatch'
+ */
+
+ if (bbPtr->flags & BB_BEGINCATCH) {
+ /*
+ * If the block begins a catch, the state for the successor is 'in
+ * catch'. The jump target is the exception exit, and the state of the
+ * jump target is 'caught.'
+ */
+
+ fallThruEnclosing = bbPtr;
+ fallThruState = BBCS_INCATCH;
+ jumpEnclosing = bbPtr;
+ jumpState = BBCS_CAUGHT;
+ ++catchDepth;
+ }
+
+ if (bbPtr->flags & BB_ENDCATCH) {
+ /*
+ * If the block ends a catch, the state for the successor is whatever
+ * the state was on entry to the catch.
+ */
+
+ if (enclosing == NULL) {
+ if (assemEnvPtr->flags & TCL_EVAL_DIRECT) {
+ Tcl_SetObjResult(interp, Tcl_NewStringObj(
+ "endCatch without a corresponding beginCatch", -1));
+ Tcl_SetErrorLine(interp, bbPtr->startLine);
+ Tcl_SetErrorCode(interp, "TCL", "ASSEM", "BADENDCATCH", NULL);
+ }
+ return TCL_ERROR;
+ }
+ fallThruEnclosing = enclosing->enclosingCatch;
+ fallThruState = enclosing->catchState;
+ --catchDepth;
+ }
+
+ /*
+ * Visit any successor blocks with the appropriate exception context
+ */
+
+ result = TCL_OK;
+ if (bbPtr->flags & BB_FALLTHRU) {
+ result = ProcessCatchesInBasicBlock(assemEnvPtr, bbPtr->successor1,
+ fallThruEnclosing, fallThruState, catchDepth);
+ }
+ if (result == TCL_OK && bbPtr->jumpTarget != NULL) {
+ entry = Tcl_FindHashEntry(&assemEnvPtr->labelHash,
+ Tcl_GetString(bbPtr->jumpTarget));
+ jumpTarget = (BasicBlock*)Tcl_GetHashValue(entry);
+ result = ProcessCatchesInBasicBlock(assemEnvPtr, jumpTarget,
+ jumpEnclosing, jumpState, catchDepth);
+ }
+
+ /*
+ * All blocks referenced in a jump table are successors.
+ */
+
+ if (bbPtr->flags & BB_JUMPTABLE) {
+ for (jtEntry = Tcl_FirstHashEntry(&bbPtr->jtPtr->hashTable,&jtSearch);
+ result == TCL_OK && jtEntry != NULL;
+ jtEntry = Tcl_NextHashEntry(&jtSearch)) {
+ targetLabel = (Tcl_Obj*)Tcl_GetHashValue(jtEntry);
+ entry = Tcl_FindHashEntry(&assemEnvPtr->labelHash,
+ Tcl_GetString(targetLabel));
+ jumpTarget = (BasicBlock*)Tcl_GetHashValue(entry);
+ result = ProcessCatchesInBasicBlock(assemEnvPtr, jumpTarget,
+ jumpEnclosing, jumpState, catchDepth);
+ }
+ }
+
+ return result;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * CheckForUnclosedCatches --
+ *
+ * Checks that a sequence of assembly code has no unclosed catches on
+ * exit.
+ *
+ * Results:
+ * Returns a standard Tcl result, with an error message for unclosed
+ * catches.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static int
+CheckForUnclosedCatches(
+ AssemblyEnv* assemEnvPtr) /* Assembly environment */
+{
+ CompileEnv* envPtr = assemEnvPtr->envPtr;
+ /* Compilation environment */
+ Tcl_Interp* interp = (Tcl_Interp*) envPtr->iPtr;
+ /* Tcl interpreter */
+
+ if (assemEnvPtr->curr_bb->catchState >= BBCS_INCATCH) {
+ if (assemEnvPtr->flags & TCL_EVAL_DIRECT) {
+ Tcl_SetObjResult(interp, Tcl_NewStringObj(
+ "catch still active on exit from assembly code", -1));
+ Tcl_SetErrorLine(interp,
+ assemEnvPtr->curr_bb->enclosingCatch->startLine);
+ Tcl_SetErrorCode(interp, "TCL", "ASSEM", "UNCLOSEDCATCH", NULL);
+ }
+ return TCL_ERROR;
+ }
+ return TCL_OK;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * BuildExceptionRanges --
+ *
+ * Walks through the assembly code and builds exception ranges for the
+ * catches embedded therein.
+ *
+ * Results:
+ * Returns a standard Tcl result with an error message in the interpreter
+ * if anything is unsuccessful.
+ *
+ * Side effects:
+ * Each contiguous block of code with a given catch exit is assigned an
+ * exception range at the appropriate level.
+ * Exception ranges in embedded blocks have their levels corrected and
+ * collated into the table.
+ * Blocks that end with 'beginCatch' are associated with the innermost
+ * exception range of the following block.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static int
+BuildExceptionRanges(
+ AssemblyEnv* assemEnvPtr) /* Assembly environment */
+{
+ CompileEnv* envPtr = assemEnvPtr->envPtr;
+ /* Compilation environment */
+ BasicBlock* bbPtr; /* Current basic block */
+ BasicBlock* prevPtr = NULL; /* Previous basic block */
+ int catchDepth = 0; /* Current catch depth */
+ int maxCatchDepth = 0; /* Maximum catch depth in the program */
+ BasicBlock** catches; /* Stack of catches in progress */
+ int* catchIndices; /* Indices of the exception ranges of catches
+ * in progress */
+ int i;
+
+ /*
+ * Determine the max catch depth for the entire assembly script
+ * (excluding embedded eval's and expr's, which will be handled later).
+ */
+
+ for (bbPtr=assemEnvPtr->head_bb; bbPtr != NULL; bbPtr=bbPtr->successor1) {
+ if (bbPtr->catchDepth > maxCatchDepth) {
+ maxCatchDepth = bbPtr->catchDepth;
+ }
+ }
+
+ /*
+ * Allocate memory for a stack of active catches.
+ */
+
+ catches = (BasicBlock**)ckalloc(maxCatchDepth * sizeof(BasicBlock*));
+ catchIndices = (int *)ckalloc(maxCatchDepth * sizeof(int));
+ for (i = 0; i < maxCatchDepth; ++i) {
+ catches[i] = NULL;
+ catchIndices[i] = -1;
+ }
+
+ /*
+ * Walk through the basic blocks and manage exception ranges.
+ */
+
+ for (bbPtr=assemEnvPtr->head_bb; bbPtr != NULL; bbPtr=bbPtr->successor1) {
+ UnstackExpiredCatches(envPtr, bbPtr, catchDepth, catches,
+ catchIndices);
+ LookForFreshCatches(bbPtr, catches);
+ StackFreshCatches(assemEnvPtr, bbPtr, catchDepth, catches,
+ catchIndices);
+
+ /*
+ * If the last block was a 'begin catch', fill in the exception range.
+ */
+
+ catchDepth = bbPtr->catchDepth;
+ if (prevPtr != NULL && (prevPtr->flags & BB_BEGINCATCH)) {
+ TclStoreInt4AtPtr(catchIndices[catchDepth-1],
+ envPtr->codeStart + bbPtr->startOffset - 4);
+ }
+
+ prevPtr = bbPtr;
+ }
+
+ /* Make sure that all catches are closed */
+
+ if (catchDepth != 0) {
+ Tcl_Panic("unclosed catch at end of code in "
+ "tclAssembly.c:BuildExceptionRanges, can't happen");
+ }
+
+ /* Free temp storage */
+
+ ckfree(catchIndices);
+ ckfree(catches);
+
+ return TCL_OK;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * UnstackExpiredCatches --
+ *
+ * Unstacks and closes the exception ranges for any catch contexts that
+ * were active in the previous basic block but are inactive in the
+ * current one.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static void
+UnstackExpiredCatches(
+ CompileEnv* envPtr, /* Compilation environment */
+ BasicBlock* bbPtr, /* Basic block being processed */
+ int catchDepth, /* Depth of nesting of catches prior to entry
+ * to this block */
+ BasicBlock** catches, /* Array of catch contexts */
+ int* catchIndices) /* Indices of the exception ranges
+ * corresponding to the catch contexts */
+{
+ ExceptionRange* range; /* Exception range for a specific catch */
+ BasicBlock* block; /* Catch block being examined */
+ BasicBlockCatchState catchState;
+ /* State of the code relative to the catch
+ * block being examined ("in catch" or
+ * "caught"). */
+
+ /*
+ * Unstack any catches that are deeper than the nesting level of the basic
+ * block being entered.
+ */
+
+ while (catchDepth > bbPtr->catchDepth) {
+ --catchDepth;
+ if (catches[catchDepth] != NULL) {
+ range = envPtr->exceptArrayPtr + catchIndices[catchDepth];
+ range->numCodeBytes = bbPtr->startOffset - range->codeOffset;
+ catches[catchDepth] = NULL;
+ catchIndices[catchDepth] = -1;
+ }
+ }
+
+ /*
+ * Unstack any catches that don't match the basic block being entered,
+ * either because they are no longer part of the context, or because the
+ * context has changed from INCATCH to CAUGHT.
+ */
+
+ catchState = bbPtr->catchState;
+ block = bbPtr->enclosingCatch;
+ while (catchDepth > 0) {
+ --catchDepth;
+ if (catches[catchDepth] != NULL) {
+ if (catches[catchDepth] != block || catchState >= BBCS_CAUGHT) {
+ range = envPtr->exceptArrayPtr + catchIndices[catchDepth];
+ range->numCodeBytes = bbPtr->startOffset - range->codeOffset;
+ catches[catchDepth] = NULL;
+ catchIndices[catchDepth] = -1;
+ }
+ catchState = block->catchState;
+ block = block->enclosingCatch;
+ }
+ }
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * LookForFreshCatches --
+ *
+ * Determines whether a basic block being entered needs any exception
+ * ranges that are not already stacked.
+ *
+ * Does not create the ranges: this procedure iterates from the innermost
+ * catch outward, but exception ranges must be created from the outermost
+ * catch inward.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static void
+LookForFreshCatches(
+ BasicBlock* bbPtr, /* Basic block being entered */
+ BasicBlock** catches) /* Array of catch contexts that are already
+ * entered */
+{
+ BasicBlockCatchState catchState;
+ /* State ("in catch" or "caught") of the
+ * current catch. */
+ BasicBlock* block; /* Current enclosing catch */
+ int catchDepth; /* Nesting depth of the current catch */
+
+ catchState = bbPtr->catchState;
+ block = bbPtr->enclosingCatch;
+ catchDepth = bbPtr->catchDepth;
+ while (catchDepth > 0) {
+ --catchDepth;
+ if (catches[catchDepth] != block && catchState < BBCS_CAUGHT) {
+ catches[catchDepth] = block;
+ }
+ catchState = block->catchState;
+ block = block->enclosingCatch;
+ }
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * StackFreshCatches --
+ *
+ * Make ExceptionRange records for any catches that are in the basic
+ * block being entered and were not in the previous basic block.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static void
+StackFreshCatches(
+ AssemblyEnv* assemEnvPtr, /* Assembly environment */
+ BasicBlock* bbPtr, /* Basic block being processed */
+ int catchDepth, /* Depth of nesting of catches prior to entry
+ * to this block */
+ BasicBlock** catches, /* Array of catch contexts */
+ int* catchIndices) /* Indices of the exception ranges
+ * corresponding to the catch contexts */
+{
+ CompileEnv* envPtr = assemEnvPtr->envPtr;
+ /* Compilation environment */
+ ExceptionRange* range; /* Exception range for a specific catch */
+ BasicBlock* block; /* Catch block being examined */
+ BasicBlock* errorExit; /* Error exit from the catch block */
+ Tcl_HashEntry* entryPtr;
+
+ catchDepth = 0;
+
+ /*
+ * Iterate through the enclosing catch blocks from the outside in,
+ * looking for ones that don't have exception ranges (and are uncaught)
+ */
+
+ for (catchDepth = 0; catchDepth < bbPtr->catchDepth; ++catchDepth) {
+ if (catchIndices[catchDepth] == -1 && catches[catchDepth] != NULL) {
+ /*
+ * Create an exception range for a block that needs one.
+ */
+
+ block = catches[catchDepth];
+ catchIndices[catchDepth] =
+ TclCreateExceptRange(CATCH_EXCEPTION_RANGE, envPtr);
+ range = envPtr->exceptArrayPtr + catchIndices[catchDepth];
+ range->nestingLevel = envPtr->exceptDepth + catchDepth;
+ envPtr->maxExceptDepth =
+ TclMax(range->nestingLevel + 1, envPtr->maxExceptDepth);
+ range->codeOffset = bbPtr->startOffset;
+
+ entryPtr = Tcl_FindHashEntry(&assemEnvPtr->labelHash,
+ Tcl_GetString(block->jumpTarget));
+ if (entryPtr == NULL) {
+ Tcl_Panic("undefined label in tclAssembly.c:"
+ "BuildExceptionRanges, can't happen");
+ }
+
+ errorExit = (BasicBlock*)Tcl_GetHashValue(entryPtr);
+ range->catchOffset = errorExit->startOffset;
+ }
+ }
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * RestoreEmbeddedExceptionRanges --
+ *
+ * Processes an assembly script, replacing any exception ranges that
+ * were present in embedded code.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static void
+RestoreEmbeddedExceptionRanges(
+ AssemblyEnv* assemEnvPtr) /* Assembly environment */
+{
+ CompileEnv* envPtr = assemEnvPtr->envPtr;
+ /* Compilation environment */
+ BasicBlock* bbPtr; /* Current basic block */
+ int rangeBase; /* Base of the foreign exception ranges when
+ * they are reinstalled */
+ int rangeIndex; /* Index of the current foreign exception
+ * range as reinstalled */
+ ExceptionRange* range; /* Current foreign exception range */
+ unsigned char opcode; /* Current instruction's opcode */
+ int catchIndex; /* Index of the exception range to which the
+ * current instruction refers */
+ int i;
+
+ /*
+ * Walk the basic blocks looking for exceptions in embedded scripts.
+ */
+
+ for (bbPtr = assemEnvPtr->head_bb;
+ bbPtr != NULL;
+ bbPtr = bbPtr->successor1) {
+ if (bbPtr->foreignExceptionCount != 0) {
+ /*
+ * Reinstall the embedded exceptions and track their nesting level
+ */
+
+ rangeBase = envPtr->exceptArrayNext;
+ for (i = 0; i < bbPtr->foreignExceptionCount; ++i) {
+ range = bbPtr->foreignExceptions + i;
+ rangeIndex = TclCreateExceptRange(range->type, envPtr);
+ range->nestingLevel += envPtr->exceptDepth + bbPtr->catchDepth;
+ memcpy(envPtr->exceptArrayPtr + rangeIndex, range,
+ sizeof(ExceptionRange));
+ if (range->nestingLevel >= envPtr->maxExceptDepth) {
+ envPtr->maxExceptDepth = range->nestingLevel + 1;
+ }
+ }
+
+ /*
+ * Walk through the bytecode of the basic block, and relocate
+ * INST_BEGIN_CATCH4 instructions to the new locations
+ */
+
+ i = bbPtr->startOffset;
+ while (i < bbPtr->successor1->startOffset) {
+ opcode = envPtr->codeStart[i];
+ if (opcode == INST_BEGIN_CATCH4) {
+ catchIndex = TclGetUInt4AtPtr(envPtr->codeStart + i + 1);
+ if (catchIndex >= bbPtr->foreignExceptionBase
+ && catchIndex < (bbPtr->foreignExceptionBase +
+ bbPtr->foreignExceptionCount)) {
+ catchIndex -= bbPtr->foreignExceptionBase;
+ catchIndex += rangeBase;
+ TclStoreInt4AtPtr(catchIndex, envPtr->codeStart+i+1);
+ }
+ }
+ i += tclInstructionTable[opcode].numBytes;
+ }
+ }
+ }
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * ResetVisitedBasicBlocks --
+ *
+ * Turns off the 'visited' flag in all basic blocks at the conclusion
+ * of a pass.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static void
+ResetVisitedBasicBlocks(
+ AssemblyEnv* assemEnvPtr) /* Assembly environment */
+{
+ BasicBlock* block;
+
+ for (block = assemEnvPtr->head_bb; block != NULL;
+ block = block->successor1) {
+ block->flags &= ~BB_VISITED;
+ }
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * AddBasicBlockRangeToErrorInfo --
+ *
+ * Updates the error info of the Tcl interpreter to show a given basic
+ * block in the code.
+ *
+ * This procedure is used to label the callstack with source location
+ * information when reporting an error in stack checking.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static void
+AddBasicBlockRangeToErrorInfo(
+ AssemblyEnv* assemEnvPtr, /* Assembly environment */
+ BasicBlock* bbPtr) /* Basic block in which the error is found */
+{
+ CompileEnv* envPtr = assemEnvPtr->envPtr;
+ /* Compilation environment */
+ Tcl_Interp* interp = (Tcl_Interp*) envPtr->iPtr;
+ /* Tcl interpreter */
+ Tcl_Obj* lineNo; /* Line number in the source */
+
+ Tcl_AddErrorInfo(interp, "\n in assembly code between lines ");
+ TclNewIntObj(lineNo, bbPtr->startLine);
+ Tcl_IncrRefCount(lineNo);
+ Tcl_AppendObjToErrorInfo(interp, lineNo);
+ Tcl_AddErrorInfo(interp, " and ");
+ if (bbPtr->successor1 != NULL) {
+ Tcl_SetIntObj(lineNo, bbPtr->successor1->startLine);
+ Tcl_AppendObjToErrorInfo(interp, lineNo);
+ } else {
+ Tcl_AddErrorInfo(interp, "end of assembly code");
+ }
+ Tcl_DecrRefCount(lineNo);
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * DupAssembleCodeInternalRep --
+ *
+ * Part of the Tcl object type implementation for Tcl assembly language
+ * bytecode. We do not copy the bytecode internalrep. Instead, we return
+ * without setting copyPtr->typePtr, so the copy is a plain string copy
+ * of the assembly source, and if it is to be used as a compiled
+ * expression, it will need to be reprocessed.
+ *
+ * This makes sense, because with Tcl's copy-on-write practices, the
+ * usual (only?) time Tcl_DuplicateObj() will be called is when the copy
+ * is about to be modified, which would invalidate any copied bytecode
+ * anyway. The only reason it might make sense to copy the bytecode is if
+ * we had some modifying routines that operated directly on the internalrep,
+ * as we do for lists and dicts.
+ *
+ * Results:
+ * None.
+ *
+ * Side effects:
+ * None.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static void
+DupAssembleCodeInternalRep(
+ Tcl_Obj *srcPtr,
+ Tcl_Obj *copyPtr)
+{
+ (void)srcPtr;
+ (void)copyPtr;
+
+ return;
+}
+\f
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * FreeAssembleCodeInternalRep --
+ *
+ * Part of the Tcl object type implementation for Tcl expression
+ * bytecode. Frees the storage allocated to hold the internal rep, unless
+ * ref counts indicate bytecode execution is still in progress.
+ *
+ * Results:
+ * None.
+ *
+ * Side effects:
+ * May free allocated memory. Leaves objPtr untyped.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static void
+FreeAssembleCodeInternalRep(
+ Tcl_Obj *objPtr)
+{
+ ByteCode *codePtr = (ByteCode *)objPtr->internalRep.twoPtrValue.ptr1;
+
+ if (codePtr->refCount-- <= 1) {
+ TclCleanupByteCode(codePtr);
+ }
+ objPtr->typePtr = NULL;
+}
+\f
+/*
+ * Local Variables:
+ * mode: c
+ * c-basic-offset: 4
+ * fill-column: 78
+ * End:
+ */
OSDN Git Service
