diff options
Diffstat (limited to 'generic/tclAssembly.h')
| -rw-r--r-- | generic/tclAssembly.h | 73 |
1 files changed, 69 insertions, 4 deletions
diff --git a/generic/tclAssembly.h b/generic/tclAssembly.h index 1f67e4f..182e210 100644 --- a/generic/tclAssembly.h +++ b/generic/tclAssembly.h @@ -3,6 +3,24 @@ #include "tclCompile.h" +/* 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_DONECATCH, /* Block is nominally within a catch context + * but has passed a 'doneCatch' directive + * and wants exceptions to propagate. */ + BBCS_CAUGHT, /* Block is within a catch context and + * may be executed after an exception fires */ +} BasicBlockCatchState; + +typedef struct CodeRange { + int startOffset; /* Start offset in the bytecode array */ + int endOffset; /* End offset in the bytecode array */ +} CodeRange; + /* * Structure that defines a basic block - a linear sequence of bytecode * instructions with no jumps in or out. @@ -17,10 +35,6 @@ typedef struct BasicBlock { int jumpLine; /* Line number in the input script of the * 'jump' instruction that ends the block, * or -1 if there is no jump */ - int may_fall_thru; /* Flag == 1 if control passes from this - * block to its successor. */ - int visited; /* Flag==1 if this block has been visited - * in the stack checker*/ struct BasicBlock* predecessor; /* Predecessor of this block in the * spanning tree */ @@ -37,13 +51,55 @@ typedef struct BasicBlock { 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 */ + + 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_BEGINCATCH = (1 << 2), /* 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_DONECATCH = (1 << 3), /* Block commences with a 'doneCatch' + * directive, indicating that the program + * is finished with the body of a catch block. + */ + BB_ENDCATCH = (1 << 4), /* 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_CONCAT1, /* 1-byte unsigned-integer operand count, must be @@ -55,6 +111,11 @@ typedef enum TalInstType { ASSEM_DICT_UNSET, /* specifies key count and LVT index, consumes N operands, * produces 1, N > 0 */ + ASSEM_DONECATCH,/* Directive indicating that the body of a catch block + * is complete. Generates no instructions, affects only + * the exception ranges. */ + 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 */ @@ -131,6 +192,10 @@ typedef struct AssembleEnv { 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) */ } AssembleEnv; |