#!/usr/bin/tclsh
#
# Parse the output of 
#
# objdump -d sqlite3.o
#
# for x64 and generate a report showing:
#
# (1) Stack used by each function
# (2) Recursion paths and their aggregate stack depth
#
set getStack 0
while {![eof stdin]} {
 set line [gets stdin]
 if {[regexp {^[0-9a-f]+ <([^>]+)>:\s*$} $line all procname]} {
 set curfunc $procname
 set root($curfunc) 1
 set calls($curfunc) {}
 set calledby($curfunc) {}
 set recursive($curfunc) {}
 set stkdepth($curfunc) 0
 set getStack 1
 continue
 }
 if {[regexp {callq? +[0-9a-z]+ <([^>]+)>} $line all other]} {
 set key [list $curfunc $other]
 set callpair($key) 1
 unset -nocomplain root($curfunc)
 continue
 }
 if {[regexp {sub +\$(0x[0-9a-z]+),%[er]sp} $line all xdepth]} {
 if {$getStack} {
 scan $xdepth %x depth
 set stkdepth($curfunc) $depth
 set getStack 0
 }
 continue
 }
}

puts "****************** Stack Usage By Function ********************"
set sdlist {}
foreach f [array names stkdepth] {
 lappend sdlist [list $stkdepth($f) $f]
}
foreach sd [lsort -integer -decr -index 0 $sdlist] {
 foreach {depth fname} $sd break
 puts [format {%6d %s} $depth $fname]
}

puts "****************** Stack Usage By Recursion *******************"
foreach key [array names callpair] {
 foreach {from to} $key break
 lappend calls($from) $to
 # lappend calledby($to) $from
}
proc all_descendents {root} {
 global calls recursive
 set todo($root) $root
 set go 1
 while {$go} {
 set go 0
 foreach f [array names todo] {
 set path $todo($f)
 unset todo($f)
 if {![info exists calls($f)]} continue
 foreach x $calls($f) {
 if {$x==$root} {
 lappend recursive($root) [concat $path $root]
 } elseif {![info exists d($x)]} {
 set go 1
 set todo($x) [concat $path $x]
 set d($x) 1
 }
 }
 }
 }
 return [array names d]
}
set pathlist {}
foreach f [array names recursive] {
 all_descendents $f
 foreach m $recursive($f) {
 set depth 0
 foreach b [lrange $m 0 end-1] {
 set depth [expr {$depth+$stkdepth($b)}]
 }
 lappend pathlist [list $depth $m]
 }
}
foreach path [lsort -integer -decr -index 0 $pathlist] {
 foreach {depth m} $path break
 set first [lindex $m 0]
 puts [format {%6d %s %d} $depth $first $stkdepth($first)]
 foreach b [lrange $m 1 end] {
 puts " $b$stkdepth($b)"
 }
}