Misc #11276
Updated by normalperson (Eric Wong) almost 9 years ago
```
Not the results I was hoping for, but maybe the LoC and stack
reductions are still worth it.
This reduces lines of code, reduces stack usage due to smaller
anchor (replaced with list_head), but unfortunately also makes the
compiled binary bigger.
On x86-64 (gcc 4.7.2)
text data bss dec hex filename
99076 1480 152 100708 18964 compile.o
93110 1480 152 94742 17216 compile.o-orig
scripts/checkstack.pl in Linux kernel shows reductions in
some functions as well as fewer functions having over
100:
before:
1 0x00002fb3 iseq_compile_each [compile]: 1224
2 0x000030d8 iseq_compile_each [compile]: 1224
3 0x00012a33 rb_iseq_build_from_ary [compile]: 392
4 0x00013d3d rb_iseq_build_from_ary [compile]: 392
5 0x00011030 setup_args [compile]: 152
6 0x000114f7 setup_args [compile]: 152
7 0x000116ad rb_iseq_compile_node [compile]: 152
8 0x00011dcb rb_iseq_compile_node [compile]: 152
9 0x00000bc0 iseq_set_sequence [compile]: 104
10 0x00000f20 iseq_set_sequence [compile]: 104
11 0x00002116 new_insn_body [compile]: 104
12 0x00002271 new_insn_body [compile]: 104
13 0x0000f391 compile_massign_opt_lhs [compile]: 104
14 0x0000f520 compile_massign_opt_lhs [compile]: 104
15 0x0000f54e compile_massign_opt_lhs [compile]: 104
16 0x0000f56d add_ensure_iseq [compile]: 104
17 0x0000f8b0 add_ensure_iseq [compile]: 104
18 0x000103e3 defined_expr [compile]: 104
19 0x000106ab defined_expr [compile]: 104
after:
1 0x00002f33 iseq_compile_each [compile]: 1032
2 0x00003070 iseq_compile_each [compile]: 1032
3 0x00013f93 rb_iseq_build_from_ary [compile]: 392
4 0x00015f14 rb_iseq_build_from_ary [compile]: 392
5 0x00012a5d rb_iseq_compile_node [compile]: 152
6 0x0001336b rb_iseq_compile_node [compile]: 152
7 0x00012450 setup_args [compile]: 120
8 0x000128f3 setup_args [compile]: 120
9 0x00000c20 iseq_set_sequence [compile]: 104
10 0x00000fad iseq_set_sequence [compile]: 104
11 0x00002766 new_insn_body [compile]: 104
12 0x000028b9 new_insn_body [compile]: 104
13 0x00010651 compile_massign_opt_lhs [compile]: 104
14 0x000107e0 compile_massign_opt_lhs [compile]: 104
15 0x0001080e compile_massign_opt_lhs [compile]: 104
16 0x00011733 defined_expr [compile]: 104
17 0x00011a10 defined_expr [compile]: 104
compile.c | 451 +++++++++++++++++++++-----------------------------------------
1 file changed, 152 insertions(+), 299 deletions(-)
```