* generic/tclCompile.c: New instruction code INST_START_CMD

	* generic/tclCompile.h:     that allows checking the bytecode's
	* generic/tclExecute.c:     validity [Bug 729692] and the interp's
	* tests/interp.test (18.9): readyness [Bug 495830] before running
	* tests/proc.test (7.1):    the command. It also changes the
	* tests/rename.test (6.1):  mechanics of the async tests in TEBC,
	doing it now at command start instead of every 16 instructions.

1 files changed, 46 insertions, 34 deletions

diff --git a/generic/tclExecute.c b/generic/tclExecute.c
index 2a313d2..3ff411d 100644
--- a/generic/tclExecute.c
+++ b/generic/tclExecute.c
@@ -11,7 +11,7 @@
  * See the file "license.terms" for information on usage and redistribution
  * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
  *
- * RCS: @(#) $Id: tclExecute.c,v 1.121 2004/01/18 16:19:05 dkf Exp $
+ * RCS: @(#) $Id: tclExecute.c,v 1.122 2004/03/30 16:22:21 msofer Exp $
  */
 
 #include "tclInt.h"
@@ -61,15 +61,6 @@ int errno;
 #   endif /* MAXDOUBLE */
 #endif /* !DBL_MAX */
 
-/*
- * A mask (should be 2**n-1) that is used to work out when the
- * bytecode engine should call Tcl_AsyncReady() to see whether there
- * is a signal that needs handling.
- */
-
-#ifndef ASYNC_CHECK_COUNT_MASK
-#   define ASYNC_CHECK_COUNT_MASK	15
-#endif /* !ASYNC_CHECK_COUNT_MASK */
 
 /*
  * Boolean flag indicating whether the Tcl bytecode interpreter has been
@@ -1098,9 +1089,11 @@ TclExecuteByteCode(interp, codePtr)
     int traceInstructions = (tclTraceExec == 3);
     char cmdNameBuf[21];
 #endif
-    int instructionCount = 0;	/* Counter that is used to work out
-				 * when to call Tcl_AsyncReady() */
-
+    Namespace *namespacePtr;
+    int codeCompileEpoch = codePtr->compileEpoch;
+    int codeNsEpoch = codePtr->nsEpoch;
+    int codePrecompiled = (codePtr->flags & TCL_BYTECODE_PRECOMPILED);
+    
     /*
      * The execution uses a unified stack: first the catch stack, immediately
      * above it the execution stack.
@@ -1134,6 +1127,11 @@ TclExecuteByteCode(interp, codePtr)
     iPtr->stats.numExecutions++;
 #endif
 
+    if (iPtr->varFramePtr != NULL) {
+        namespacePtr = iPtr->varFramePtr->nsPtr;
+    } else {
+        namespacePtr = iPtr->globalNsPtr;
+    }
 
     /*
      * Loop executing instructions until a "done" instruction, a 
@@ -1215,21 +1213,43 @@ TclExecuteByteCode(interp, codePtr)
     iPtr->stats.instructionCount[*pc]++;
 #endif
 
-    /*
-     * Check for asynchronous handlers [Bug 746722]; we
-     * do the check every 16th instruction.
-     */
+    switch (*pc) {
+    case INST_START_CMD:
+	/*
+	 * Check for asynchronous handlers [Bug 746722].
+	 */
 
-    if (!(instructionCount++ & ASYNC_CHECK_COUNT_MASK) && Tcl_AsyncReady()) {
-	DECACHE_STACK_INFO();
-	result = Tcl_AsyncInvoke(interp, result);
-	CACHE_STACK_INFO();
-	if (result == TCL_ERROR) {
-	    goto checkForCatch;
+	if (Tcl_AsyncReady()) {
+	    DECACHE_STACK_INFO();
+	    result = Tcl_AsyncInvoke(interp, result);
+	    CACHE_STACK_INFO();
+	    if (result == TCL_ERROR) {
+		goto checkForCatch;
+	    }
 	}
-    }
-
-    switch (*pc) {
+	
+	if ((!(iPtr->flags & DELETED)
+		    && (codeCompileEpoch == iPtr->compileEpoch)
+		    && (codeNsEpoch == namespacePtr->resolverEpoch))
+		|| codePrecompiled) {
+	    NEXT_INST_F(5, 0, 0);
+	} else {
+	    bytes = GetSrcInfoForPc(pc, codePtr, &length);
+	    result = Tcl_EvalEx(interp, bytes, length, 0);
+	    if (result != TCL_OK) {
+		goto checkForCatch;
+	    }
+	    opnd = TclGetUInt4AtPtr(pc+1);
+	    objResultPtr = Tcl_GetObjResult(interp);
+	    {
+		Tcl_Obj *newObjResultPtr;
+		TclNewObj(newObjResultPtr);
+		Tcl_IncrRefCount(newObjResultPtr);
+		iPtr->objResultPtr = newObjResultPtr;
+	    }
+	    NEXT_INST_V(opnd, 0, -1);
+	}
+	
     case INST_RETURN:
 	{
 	    int code = TclGetInt4AtPtr(pc+1);
@@ -1532,14 +1552,6 @@ TclExecuteByteCode(interp, codePtr)
 	    ++*preservedStackRefCountPtr;
 
 	    /*
-	     * Reset the instructionCount variable, since we're about
-	     * to check for async stuff anyway while processing
-	     * TclEvalObjvInternal.
-	     */
-
-	    instructionCount = 1;
-
-	    /*
 	     * Finally, let TclEvalObjvInternal handle the command. 
 	     */