diff options
Diffstat (limited to 'generic/tclCompile.c')
| -rw-r--r-- | generic/tclCompile.c | 81 |
1 files changed, 32 insertions, 49 deletions
diff --git a/generic/tclCompile.c b/generic/tclCompile.c index d82d728..6ac5fb9 100644 --- a/generic/tclCompile.c +++ b/generic/tclCompile.c @@ -1885,47 +1885,41 @@ CompileCmdCompileProc( Tcl_Interp *interp, Tcl_Parse *parsePtr, Command *cmdPtr, - int startCodeOffset, CompileEnv *envPtr) { int savedNumCmds = envPtr->numCommands; int startStackDepth = envPtr->currStackDepth; - int update = 0; + int startCodeOffset = envPtr->codeNext - envPtr->codeStart; + int incrOffset = -1; DefineLineInformation; /* - * Mark the start of the command; the proper bytecode - * length will be updated later. There is no need to - * do this for the first bytecode in the compile env, - * as the check is done before calling - * TclNRExecuteByteCode(). Do emit an INST_START_CMD - * in special cases where the first bytecode is in a - * loop, to insure that the corresponding command is - * counted properly. Compilers for commands able to - * produce such a beast (currently 'while 1' only) set - * envPtr->atCmdStart to 0 in order to signal this - * case. [Bug 1752146] + * Emit of the INST_START_CMD instruction is controlled by + * the value of envPtr->atCmdStart: * - * Note that the environment is initialised with - * atCmdStart=1 to avoid emitting ISC for the first - * command. + * atCmdStart == 2 : We are not using the INST_START_CMD instruction. + * atCmdStart == 1 : INST_START_CMD was the last instruction emitted. + * : We do not need to emit another. Instead we + * : increment the number of cmds started at it (except + * : for the special case at the start of a script.) + * atCmdStart == 0 : The last instruction was something else. We need + * : to emit INST_START_CMD here. */ - if (envPtr->atCmdStart == 1) { - if (startCodeOffset) { - /* - * Increase the number of commands being - * started at the current point. Note that - * this depends on the exact layout of the - * INST_START_CMD's operands, so be careful! - */ - - TclIncrUInt4AtPtr(envPtr->codeNext - 4, 1) - } - } else if (envPtr->atCmdStart == 0) { + switch (envPtr->atCmdStart) { + case 0: TclEmitInstInt4(INST_START_CMD, 0, envPtr); - TclEmitInt4(1, envPtr); - update = 1; + incrOffset = envPtr->codeNext - envPtr->codeStart; + TclEmitInt4(0, envPtr); + break; + case 1: + if (envPtr->codeNext > envPtr->codeStart) { + incrOffset = envPtr->codeNext - 4 - envPtr->codeStart; + } + break; + case 2: + /* Nothing to do */ + ; } if (TCL_OK == cmdPtr->compileProc(interp, parsePtr, cmdPtr, envPtr)) { @@ -1947,30 +1941,20 @@ CompileCmdCompileProc( parsePtr->tokenPtr->start, diff); } #endif - if (update) { + if (incrOffset >= 0) { /* - * Fix the bytecode length. + * We successfully compiled a command. Increment the number + * of commands that start at the currently active INST_START_CMD. */ + unsigned char *incrPtr = envPtr->codeStart + incrOffset; + unsigned char *startPtr = incrPtr - 5; - unsigned char *fixPtr = envPtr->codeStart + startCodeOffset + 1; - unsigned fixLen = envPtr->codeNext - fixPtr + 1; - - TclStoreInt4AtPtr(fixLen, fixPtr); + TclIncrUInt4AtPtr(incrPtr, 1); + TclStoreInt4AtPtr(envPtr->codeNext - startPtr, startPtr + 1); } return TCL_OK; } - if (envPtr->atCmdStart == 1 && startCodeOffset != 0) { - /* - * Decrease the number of commands being started - * at the current point. Note that this depends on - * the exact layout of the INST_START_CMD's - * operands, so be careful! - */ - - TclIncrUInt4AtPtr(envPtr->codeNext - 4, -1); - } - /* * Restore numCommands, codeNext, and currStackDepth to their * correct values, removing any commands compiled before the @@ -2069,8 +2053,7 @@ CompileCommandTokens( /* If cmdPtr != NULL, we will try to call cmdPtr->compileProc */ if (cmdPtr) { - code = CompileCmdCompileProc(interp, parsePtr, cmdPtr, - startCodeOffset, envPtr); + code = CompileCmdCompileProc(interp, parsePtr, cmdPtr, envPtr); } if (code == TCL_ERROR) { |