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Diffstat (limited to 'NOTES')
| -rw-r--r-- | NOTES | 99 |
1 files changed, 99 insertions, 0 deletions
@@ -1,4 +1,81 @@ +------------------------------------------------------------------------ +Description of the new macros to control feature exclusion and +stack handling +------------------------------------------------------------------------ + +All the macros reside in "generic/tclInt.h" and can be set in the +build environment. Especially the macros controlling usage of stack +are setup in such a way that a value defined in the build environment +takes priority over the value defined in the header. + +Feature exclusion. Simply define any of the macros below to exclude +the associated feature of the core. + + TCL_NO_SOCKETS /* Disable "tcp" channel driver */ + TCL_NO_TTY /* Disable "tty" channel driver */ + TCL_NO_PIPES /* Disable "pipe" channel driver */ + TCL_NO_PIDCMD /* Disable "pid" command */ + TCL_NO_NONSTDCHAN /* Disable creation of channels beyond std* */ + TCL_NO_CHANNELCOPY /* Disable channel copying, C/Tcl [fcopy] */ + TCL_NO_CHANNEL_READ /* Disable Tcl_ReadChars, [read] */ + TCL_NO_CHANNEL_EOF /* Disable [eof] */ + TCL_NO_CHANNEL_CONFIG /* Disable [fconfigure] and Tcl_GetChannelOption */ + TCL_NO_CHANNEL_BLOCKED /* Disable [fblocked] */ + TCL_NO_FILEEVENTS /* Disable [fileevent] and underlying APIs */ + TCL_NO_FILESYSTEM /* Disable everything related to the filesystem */ + TCL_NO_LOADCMD /* Disable [load] and machinery below */ + TCL_NO_SLAVEINTERP /* No slave interp's */ + TCL_NO_CMDALIASES /* No command aliases */ + + MODULAR_TCL /* All of the above */ + +Controlling the stack. Define TCL_STRUCT_ON_HEAP to switch a number a +of structures to allocation off the heap. The other macros are numeric +and define how many variables of a kind are placed on the stack by the +functions using the macros. + + TCL_STRUCT_ON_HEAP /* Allocate temp. big structures off the heap */ + +* TCL_FMT_STATIC_FLOATBUFFER_SZ 320 /* size of various information placed */ + TCL_FMT_STATIC_VALIDATE_LIST 16 /* on the stack */ +* TCL_FOREACH_STATIC_ARGS 9 +* TCL_FOREACH_STATIC_LIST_SZ 4 + TCL_FOREACH_STATIC_VARLIST_SZ 5 +* TCL_RESULT_APPEND_STATIC_LIST_SZ 16 + TCL_MERGE_STATIC_LIST_SZ 20 +* TCL_PROC_STATIC_CLOCALS 20 + TCL_PROC_STATIC_ARGS 20 + TCL_INVOKE_STATIC_ARGS 20 + TCL_EVAL_STATIC_VARCHARS 30 + TCL_STATS_COUNTERS 10 + TCL_LSORT_STATIC_MERGE_BUCKETS 30 + +* TCL_DSTRING_STATIC_SIZE 200 /* Exception: Resides in "tcl.h" */ + +Only the macros marked by '*' have been tested so far (-Dxxx=1). This +means that usage of the other macros may result in a crash +(FLOATBUFFER... for example did for while). + +It is advisable to use "-O" when compiling the core so that the +compiler optimizes the allocation of local variables on the stack, +i.e. collapsing variables with non-overlapping lifetimes into one +memory location. + + + + +------------------------------------------------------------------------ +------------------------------------------------------------------------ +------------------------------------------------------------------------ + + Scratchpad + Everything below may change at will. + +------------------------------------------------------------------------ +------------------------------------------------------------------------ +------------------------------------------------------------------------ + Pre-notes The cutting of the channel system is not as clean as I would like @@ -257,3 +334,25 @@ TclObjInterpProc TclInvokeStringCommand TCL_INVOKE_STATIC_ARGS => 20 x char* = 80 + +TclExecuteByte + Uses 868 btes of stack. where ? .... + compiler places all local variables immediately on stack, + independent of where defined (i.e. even variables declared in sub + scopes are placed immediately.) + 868 -> /4 about 217 variables ... Yes, that it is on the order of + variables declared in this behemoth + + Why variables with non-intersecting lieftimes collapsed into + one memory location ? ... Ok, compilation was just -g, without + any optimizations ... + + Compile -g -O => 480 bytes stack + compile -g -O2 => 460 bytes stack + + ! Ok compiling the whole instrumented core with -g -O to + get standard stack usage numbers. + + => Have to comile baseline with that as well. + +Also look for variable decl. hidden in intenrl blocks. ... |