From: ZheNing Hu <adlternative@xxxxxxxxx>
In format_ref_array_item(), we add the object data
to ref_formatting_state, and copy the data from
ref_formatting_state to final_buf at the end. There
are huge copies of data.
Because final_buf will be cleared before every time
we call format_ref_array_item(). So we actually add
content to an empty strbuf. We can add the object's
data directly to this final_buffer instead of adding
objects' data to state.stack->output first, then
copy to final_buf.
Add a can_reuse_final_buffer flag to struct ref_format
and create can_reuse_final_buffer() to check if we are
use %(align), %(end), %(if), %(then), %(else). If not,
we can reuse the buf of finnal_buf.
Reuse the buffer address of final_buf in
format_ref_array_item(), we directly add the data to the
final buffer, return the content to final_buf at the end.
This will bring performance improvements.
Mentored-by: Christian Couder <christian.couder@xxxxxxxxx>
Mentored-by: Hariom Verma <hariom18599@xxxxxxxxx>
Signed-off-by: ZheNing Hu <adlternative@xxxxxxxxx>
---
ref-filter.c | 39 ++++++++++++++++++++++++++++++++++-----
ref-filter.h | 3 ++-
2 files changed, 36 insertions(+), 6 deletions(-)
diff --git a/ref-filter.c b/ref-filter.c
index 76a31fb79b1..7106d4c1c4c 100644
--- a/ref-filter.c
+++ b/ref-filter.c
@@ -1023,6 +1023,19 @@ static int need_parse_buffer(enum atom_type atom_type) {
}
}
+static int can_reuse_final_buffer(enum atom_type atom_type) {
+ switch (atom_type) {
+ case ATOM_ALIGN:
+ case ATOM_END:
+ case ATOM_IF:
+ case ATOM_THEN:
+ case ATOM_ELSE:
+ return 0;
+ default:
+ return 1;
+ }
+}
+
/*
* Make sure the format string is well formed, and parse out
* the used atoms.
@@ -1054,6 +1067,7 @@ int verify_ref_format(struct ref_format *format)
format->can_skip_parse_buffer = 0;
if (reject_atom(used_atom[at].atom_type))
die(_("this command reject atom %%(%.*s)"), (int)(ep - sp - 2), sp + 2);
+ format->can_reuse_final_buffer = can_reuse_final_buffer(used_atom[at].atom_type);
if ((format->quote_style == QUOTE_PYTHON ||
format->quote_style == QUOTE_SHELL ||
@@ -2627,7 +2641,14 @@ int format_ref_array_item(struct ref_array_item *info,
struct ref_formatting_state state = REF_FORMATTING_STATE_INIT;
state.quote_style = format->quote_style;
- push_stack_element(&state.stack);
+ if (format->can_reuse_final_buffer) {
+ struct ref_formatting_stack *s = xmalloc(sizeof(struct ref_formatting_stack));
+ s->output = *final_buf;
+ s->prev = state.stack;
+ state.stack = s;
+ } else {
+ push_stack_element(&state.stack);
+ }
info->can_skip_parse_buffer = format->can_skip_parse_buffer;
cp = format->format;
@@ -2641,7 +2662,8 @@ int format_ref_array_item(struct ref_array_item *info,
append_literal(cp, e->beg - 2, &state);
if (get_ref_atom_value(info, e->at, &atomv, error_buf) ||
atomv->handler(atomv, &state, error_buf)) {
- pop_stack_element(&state.stack);
+ if (!format->can_reuse_final_buffer)
+ pop_stack_element(&state.stack);
return -1;
}
cp = e->end + 1;
@@ -2656,16 +2678,23 @@ int format_ref_array_item(struct ref_array_item *info,
struct atom_value resetv = ATOM_VALUE_INIT;
resetv.s = GIT_COLOR_RESET;
if (append_atom(&resetv, &state, error_buf)) {
- pop_stack_element(&state.stack);
+ if (!format->can_reuse_final_buffer)
+ pop_stack_element(&state.stack);
return -1;
}
}
if (state.stack->prev) {
+ assert(!format->can_reuse_final_buffer);
pop_stack_element(&state.stack);
return strbuf_addf_ret(error_buf, -1, _("format: %%(end) atom missing"));
}
- strbuf_addbuf(final_buf, &state.stack->output);
- pop_stack_element(&state.stack);
+ if(format->can_reuse_final_buffer) {
+ *final_buf = state.stack->output;
+ free(state.stack);
+ } else {
+ strbuf_addbuf(final_buf, &state.stack->output);
+ pop_stack_element(&state.stack);
+ }
return 0;
}
diff --git a/ref-filter.h b/ref-filter.h
index df54836a643..a62a14a2e43 100644
--- a/ref-filter.h
+++ b/ref-filter.h
@@ -92,10 +92,11 @@ struct ref_format {
int can_skip_parse_buffer;
/* Internal state to ref-filter */
int need_color_reset_at_eol;
+ int can_reuse_final_buffer;
struct list_head parsed_atom_head;
};
-#define REF_FORMAT_INIT { .use_color = -1, .can_skip_parse_buffer = 1 }
+#define REF_FORMAT_INIT { .use_color = -1, .can_skip_parse_buffer = 1, .can_reuse_final_buffer = 1 }
/* Macros for checking --merged and --no-merged options */
#define _OPT_MERGED_NO_MERGED(option, filter, h) \
--
gitgitgadget
