From 34d2b6e96c0b90ef69a09ba51d9365b48b937feb Mon Sep 17 00:00:00 2001 From: Takashi Sakamoto Date: Thu, 14 Jul 2016 23:07:32 +0900 Subject: [PATCH] pcm: remove alloca() from snd_pcm_hw_get_chmap() Both of alloca() and automatic variables keeps storages on stack, while the former generates more instructions than the latter. It's better to use the latter if the size of storage is computable at pre-compile or compile time; i.e. just for structures. This commit obsolete usages of alloca() with automatic variables. Signed-off-by: Takashi Sakamoto Signed-off-by: Takashi Iwai --- src/pcm/pcm_hw.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) diff --git a/src/pcm/pcm_hw.c b/src/pcm/pcm_hw.c index e7a23939..20c233b1 100644 --- a/src/pcm/pcm_hw.c +++ b/src/pcm/pcm_hw.c @@ -1206,8 +1206,8 @@ static snd_pcm_chmap_t *snd_pcm_hw_get_chmap(snd_pcm_t *pcm) snd_pcm_hw_t *hw = pcm->private_data; snd_pcm_chmap_t *map; snd_ctl_t *ctl; - snd_ctl_elem_id_t *id; - snd_ctl_elem_value_t *val; + snd_ctl_elem_id_t id = {0}; + snd_ctl_elem_value_t val = {0}; unsigned int i; int ret; @@ -1241,11 +1241,9 @@ static snd_pcm_chmap_t *snd_pcm_hw_get_chmap(snd_pcm_t *pcm) chmap_caps_set_error(hw, CHMAP_CTL_GET); return NULL; } - snd_ctl_elem_value_alloca(&val); - snd_ctl_elem_id_alloca(&id); - fill_chmap_ctl_id(pcm, id); - snd_ctl_elem_value_set_id(val, id); - ret = snd_ctl_elem_read(ctl, val); + fill_chmap_ctl_id(pcm, &id); + snd_ctl_elem_value_set_id(&val, &id); + ret = snd_ctl_elem_read(ctl, &val); snd_ctl_close(ctl); if (ret < 0) { free(map); @@ -1254,7 +1252,7 @@ static snd_pcm_chmap_t *snd_pcm_hw_get_chmap(snd_pcm_t *pcm) return NULL; } for (i = 0; i < pcm->channels; i++) - map->pos[i] = snd_ctl_elem_value_get_integer(val, i); + map->pos[i] = snd_ctl_elem_value_get_integer(&val, i); chmap_caps_set_ok(hw, CHMAP_CTL_GET); return map; } -- 2.47.1