*: code shrink via NOINLINE

function                                             old     new   delta
expand_vars_to_list                                    -    2118   +2118
lzo1x_optimize                                         -    1429   +1429
run_pipe                                             358    1775   +1417
arith_apply                                            -    1335   +1335
mainQSort3                                             -    1198   +1198
logdir_open                                            -    1163   +1163
rewrite                                                -    1039   +1039
dump_identity                                          -     987    +987
do_shm                                                 -     884    +884
cpio_o                                                 -     863    +863
cpio_main                                           1450     560    -890
ipcs_main                                           3442    2523    -919
bb_dump_dump                                        2611    1488   -1123
process_dev                                         4572    3405   -1167
logdirs_reopen                                      1308      86   -1222
arith                                               2084     707   -1377
mainSort                                            2622    1202   -1420
do_lzo_compress                                     2276     799   -1477
run_list                                            2491     943   -1548
expand_variables                                    2280     135   -2145
------------------------------------------------------------------------------
(add/remove: 9/0 grow/shrink: 1/10 up/down: 12433/-13288)    Total: -855 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

10 files changed, 41 insertions, 10 deletions

diff --git a/archival/bz/blocksort.c b/archival/bz/blocksort.c
index 0e73ffeba..f70c3701d 100644
--- a/archival/bz/blocksort.c
+++ b/archival/bz/blocksort.c
@@ -585,7 +585,7 @@ uint8_t mmed3(uint8_t a, uint8_t b, uint8_t c)
 #define MAIN_QSORT_DEPTH_THRESH (BZ_N_RADIX + BZ_N_QSORT)
 #define MAIN_QSORT_STACK_SIZE   100
 
-static
+static NOINLINE
 void mainQSort3(uint32_t* ptr,
                 uint8_t*  block,
                 uint16_t* quadrant,
diff --git a/archival/cpio.c b/archival/cpio.c
index bb578577d..ef228990a 100644
--- a/archival/cpio.c
+++ b/archival/cpio.c
@@ -117,7 +117,7 @@ static off_t cpio_pad4(off_t size)
 
 /* Return value will become exit code.
  * It's ok to exit instead of return. */
-static int cpio_o(void)
+static NOINLINE int cpio_o(void)
 {
         static const char trailer[] ALIGN1 = "TRAILER!!!";
         struct name_s {
diff --git a/archival/lzop.c b/archival/lzop.c
index b4757e86d..5f2744d91 100644
--- a/archival/lzop.c
+++ b/archival/lzop.c
@@ -75,7 +75,7 @@ static void copy3(uint8_t* ip, const uint8_t* m_pos, unsigned off)
 #define TEST_IP         (ip < ip_end)
 #define TEST_OP         (op <= op_end)
 
-static int lzo1x_optimize(uint8_t *in, unsigned in_len,
+static NOINLINE int lzo1x_optimize(uint8_t *in, unsigned in_len,
                 uint8_t *out, unsigned *out_len,
                 void* wrkmem UNUSED_PARAM)
 {
diff --git a/docs/keep_data_small.txt b/docs/keep_data_small.txt
index 2ddbefa10..2ba24e4a1 100644
--- a/docs/keep_data_small.txt
+++ b/docs/keep_data_small.txt
@@ -214,3 +214,34 @@ Result (non-static busybox built against glibc):
    text    data     bss     dec     hex filename
  634416    2736   23856  661008   a1610 busybox
  632580    2672   22944  658196   a0b14 busybox_noalign
+
+
+
+                Keeping code small
+
+Set CONFIG_EXTRA_CFLAGS="-fno-inline-functions-called-once",
+produce "make bloatcheck", see the biggest auto-inlined functions.
+Now, set CONFIG_EXTRA_CFLAGS back to "", but add NOINLINE
+to some of these functions. In 1.16.x timeframe, the results were
+(annotated "make bloatcheck" output):
+
+function             old     new   delta
+expand_vars_to_list    -    1712   +1712 win
+lzo1x_optimize         -    1429   +1429 win
+arith_apply            -    1326   +1326 win
+read_interfaces        -    1163   +1163 loss, leave w/o NOINLINE
+logdir_open            -    1148   +1148 win
+check_deps             -    1148   +1148 loss
+rewrite                -    1039   +1039 win
+run_pipe             358    1396   +1038 win
+write_status_file      -    1029   +1029 almost the same, leave w/o NOINLINE
+dump_identity          -     987    +987 win
+mainQSort3             -     921    +921 win
+parse_one_line         -     916    +916 loss
+summarize              -     897    +897 almost the same
+do_shm                 -     884    +884 win
+cpio_o                 -     863    +863 win
+subCommand             -     841    +841 loss
+receive                -     834    +834 loss
+
+855 bytes saved in total.
diff --git a/libbb/dump.c b/libbb/dump.c
index 2e777c358..bef485eff 100644
--- a/libbb/dump.c
+++ b/libbb/dump.c
@@ -96,7 +96,7 @@ static NOINLINE int bb_dump_size(FS *fs)
         return cur_size;
 }
 
-static void rewrite(priv_dumper_t *dumper, FS *fs)
+static NOINLINE void rewrite(priv_dumper_t *dumper, FS *fs)
 {
         enum { NOTOKAY, USEBCNT, USEPREC } sokay;
         PR *pr, **nextpr = NULL;
diff --git a/miscutils/hdparm.c b/miscutils/hdparm.c
index 0917b4175..65c11ec79 100644
--- a/miscutils/hdparm.c
+++ b/miscutils/hdparm.c
@@ -1185,7 +1185,7 @@ static const char BuffType[] ALIGN1 =
         "unknown""\0"     "1Sect""\0"      "DualPort""\0"  "DualPortCache"
 ;
 
-static void dump_identity(const struct hd_driveid *id)
+static NOINLINE void dump_identity(const struct hd_driveid *id)
 {
         int i;
         const unsigned short *id_regs = (const void*) id;
diff --git a/runit/svlogd.c b/runit/svlogd.c
index 34ceadf72..b7fd15262 100644
--- a/runit/svlogd.c
+++ b/runit/svlogd.c
@@ -603,7 +603,7 @@ static void logdir_close(struct logdir *ld)
         ld->processor = NULL;
 }
 
-static unsigned logdir_open(struct logdir *ld, const char *fn)
+static NOINLINE unsigned logdir_open(struct logdir *ld, const char *fn)
 {
         char buf[128];
         unsigned now;
diff --git a/shell/hush.c b/shell/hush.c
index 3012a1f73..ec38023ff 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -2151,7 +2151,7 @@ static char *expand_pseudo_dquoted(const char *str)
  * to be filled). This routine is extremely tricky: has to deal with
  * variables/parameters with whitespace, $* and $@, and constructs like
  * 'echo -$*-'. If you play here, you must run testsuite afterwards! */
-static int expand_vars_to_list(o_string *output, int n, char *arg, char or_mask)
+static NOINLINE int expand_vars_to_list(o_string *output, int n, char *arg, char or_mask)
 {
         /* or_mask is either 0 (normal case) or 0x80 -
          * expansion of right-hand side of assignment == 1-element expand.
@@ -3750,7 +3750,7 @@ static int checkjobs_and_fg_shell(struct pipe* fg_pipe)
  * backgrounded: cmd &     { list } &
  * subshell:     ( list ) [&]
  */
-static int run_pipe(struct pipe *pi)
+static NOINLINE int run_pipe(struct pipe *pi)
 {
         static const char *const null_ptr = NULL;
         int i;
diff --git a/shell/math.c b/shell/math.c
index d75bcae3a..3791b84bc 100644
--- a/shell/math.c
+++ b/shell/math.c
@@ -293,7 +293,7 @@ arith_lookup_val(v_n_t *t, a_e_h_t *math_hooks)
 /* "applying" a token means performing it on the top elements on the integer
  * stack. For a unary operator it will only change the top element, but a
  * binary operator will pop two arguments and push a result */
-static int
+static NOINLINE int
 arith_apply(operator op, v_n_t *numstack, v_n_t **numstackptr, a_e_h_t *math_hooks)
 {
         v_n_t *numptr_m1;
diff --git a/util-linux/ipcs.c b/util-linux/ipcs.c
index 920125708..c8c6d76fa 100644
--- a/util-linux/ipcs.c
+++ b/util-linux/ipcs.c
@@ -115,7 +115,7 @@ static void print_perms(int id, struct ipc_perm *ipcp)
 }
 
 
-static void do_shm(void)
+static NOINLINE void do_shm(void)
 {
         int maxid, shmid, id;
         struct shmid_ds shmseg;