Each access to current top flag took a function call + fetch of three data items
+ multiplication and some additions + and then following the resulting pointer.
After the change, it is: fetch pointer value + one byte access via this pointer.
function old new delta
bc_parse_startBody 45 49 +4
bc_parse_free 46 47 +1
zbc_parse_auto 188 185 -3
bc_parse_push 14 11 -3
bc_vm_run 398 394 -4
zbc_vm_process 63 58 -5
zdc_parse_expr 638 632 -6
zbc_parse_body 101 95 -6
bc_parse_addFunc 31 25 -6
bc_parse_noElse 56 48 -8
zcommon_parse 341 331 -10
zbc_parse_else 134 123 -11
bc_parse_create 124 108 -16
zbc_parse_text_init 123 104 -19
zbc_parse_endBody 292 252 -40
zbc_parse_stmt 1479 1420 -59
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/14 up/down: 5/-196) Total: -191 bytes
text data bss dec hex filename
979880 485 7296 987661 f120d busybox_old
979689 485 7296 987470 f114e busybox_unstripped
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
7db384338a