diff options
Diffstat (limited to 'generic/tclCompCmdsGR.c')
| -rw-r--r-- | generic/tclCompCmdsGR.c | 25 |
1 files changed, 22 insertions, 3 deletions
diff --git a/generic/tclCompCmdsGR.c b/generic/tclCompCmdsGR.c index 0720a6b..8779a78 100644 --- a/generic/tclCompCmdsGR.c +++ b/generic/tclCompCmdsGR.c @@ -1505,7 +1505,6 @@ TclCompileLreplaceCmd( * - integer: [0,len+1] * - end index: TCL_INDEX_END * - -ive offset: TCL_INDEX_END-[len-1,0] - * - +ive offset: TCL_INDEX_END+1 */ /* @@ -1515,6 +1514,11 @@ TclCompileLreplaceCmd( */ if ((idx1 <= TCL_INDEX_END) != (idx2 <= TCL_INDEX_END)) { + + /* + * NOTE: when idx1 == 0 and idx2 == TCL_INDEX_END, + * we bail out here! Yet, down below + */ return TCL_ERROR; } @@ -1531,9 +1535,11 @@ TclCompileLreplaceCmd( if (parsePtr->numWords == 4) { if (idx1 == 0) { if (idx2 == TCL_INDEX_END) { + + /* Here we are down below! Now look somewhere else! */ goto dropAll; } - idx1 = idx2 + 1; + idx1 = idx2 + 1; /* TODO: Overflow? */ idx2 = TCL_INDEX_END; goto dropEnd; } else if (idx2 == TCL_INDEX_END) { @@ -1561,9 +1567,10 @@ TclCompileLreplaceCmd( TclEmitInstInt4( INST_REVERSE, 2, envPtr); if (idx1 == 0) { if (idx2 == TCL_INDEX_END) { + /* Another Can't Happen. */ goto replaceAll; } - idx1 = idx2 + 1; + idx1 = idx2 + 1; /* TODO: Overflow? */ idx2 = TCL_INDEX_END; goto replaceHead; } else if (idx2 == TCL_INDEX_END) { @@ -1588,6 +1595,11 @@ TclCompileLreplaceCmd( */ dropAll: /* This just ensures the arg is a list. */ + /* + * And now we're here down below the down below where flow can never go. + * CONCLUSION: This code has no purpose. + */ +Tcl_Panic("Can not get here."); TclEmitOpcode( INST_LIST_LENGTH, envPtr); TclEmitOpcode( INST_POP, envPtr); PushStringLiteral(envPtr, ""); @@ -1615,6 +1627,9 @@ TclCompileLreplaceCmd( * Emit an error if we've been given an empty list. */ +/* If we're generating bytecode to report an error, we've gone wrong. + * Just fallback to direct invocation. + */ TclEmitOpcode( INST_DUP, envPtr); TclEmitOpcode( INST_LIST_LENGTH, envPtr); offset2 = CurrentOffset(envPtr); @@ -1646,6 +1661,7 @@ TclCompileLreplaceCmd( */ replaceAll: +Tcl_Panic("Can not get here."); TclEmitOpcode( INST_LIST_LENGTH, envPtr); TclEmitOpcode( INST_POP, envPtr); goto done; @@ -1685,6 +1701,9 @@ TclCompileLreplaceCmd( * Emit an error if we've been given an empty list. */ +/* If we're generating bytecode to report an error, we've gone wrong. + * Just fallback to direct invocation. + */ TclEmitOpcode( INST_DUP, envPtr); TclEmitOpcode( INST_LIST_LENGTH, envPtr); offset2 = CurrentOffset(envPtr); |