On Sep 13, 2008, at 12:56, Andy Wingo wrote:
So for example, just sitting at the repl, we have:
[...]
#27 0x0014e99b in scm_apply (proc=0xb7f0d718, arg1=0x404,
args=0x404) at eval.i.c:1656
1656 return scm_dapply (proc, arg1, args);
(gdb)
#28 0x001c48fc in vm_run (vm=0xb7f1ff58, program=0x8d53df8,
args=0x404) at vm-i-system.c:510
510 *sp = scm_apply (x, args, SCM_EOL);
(gdb) p sp - vp->stack_base
$3 = 104
(gdb) up
#29 0x001bfcad in program_apply (program=0xb7ee2730, args=0x404)
at programs.c:126
126 return scm_vm_apply (scm_the_vm (), program, args);
(gdb) p 0x001c48fc - 0x001bfcad
$4 = 19535
The difference between #29 and #28 is the size of the vm_run() stack
frame (I think).
Aren't those the program counter addresses you're looking at? Note
that the value at #29 is in between #27 and #28. Stack frames usually
don't work that way. :-)
(gdb) bt
[...]
#7 0x00079691 in captured_main ()
#8 0x00077487 in catch_errors ()
#9 0x000796d2 in gdb_main () <---- pc address 0x796d2
#10 0x00001f1e in main ()
(gdb) x/20i gdb_main
0x79693 <gdb_main>: push %ebp
[...]
0x796c6 <gdb_main+51>: mov %ecx,0x4(%esp)
0x796ca <gdb_main+55>: mov %eax,(%esp)
0x796cd <gdb_main+58>: call 0x7743a <catch_errors>
0x796d2 <gdb_main+63>: add $0x14,%esp <---- insn to return to
0x796d5 <gdb_main+66>: mov $0x1,%eax
0x796da <gdb_main+71>: pop %ebx
(gdb)
Try "print $sp" or "info reg" at each frame to see the stack pointer.
Or you could try disassembling the entire thing, and scan for a regexp
matching near the start of a function (say, symbol name, "+", one
digit or a "1" and another digit, then ">", and an instruction that
adjusts the stack pointer by a 3-digit value or more. If it works,
that may show you all the biggest-frame functions.
Ken
