Tweaking performance.

This commit is contained in:
Daniel Lemire 2018-11-27 21:13:31 -05:00
parent 8648c4108e
commit c1805783fc
1 changed files with 9 additions and 6 deletions

View File

@ -95,15 +95,18 @@ bool unified_machine(const u8 *buf, size_t len, ParsedJson &pj) {
pj.ret_address[depth] = &&start_continue;
pj.containing_scope_offset[depth] = pj.get_current_loc();
pj.write_tape(0, 'r'); // r for root, 0 is going to get overwritten
depth++; // everything starts at depth = 1, depth = 0 is just for the root
// the root is used, if nothing else, to capture the size of the tape
depth++; // everything starts at depth = 1, depth = 0 is just for the root, the root may contain an object, an array or something else.
if (depth > pj.depthcapacity) {
goto fail;
}
UPDATE_CHAR();
switch (c) {
case '{':
pj.write_tape(0, c); // strangely, moving this to object_begin slows things down
goto object_begin;
case '[':
pj.write_tape(0, c);
goto array_begin;
#define SIMDJSON_ALLOWANYTHINGINROOT
// A JSON text is a serialized value. Note that certain previous
@ -187,7 +190,7 @@ start_continue:
object_begin:
DEBUG_PRINTF("in object_begin\n");
pj.containing_scope_offset[depth] = pj.get_current_loc();
pj.write_tape(0, c);
//pj.write_tape(0, c); // this is a bad spot to do this performance-wise
UPDATE_CHAR();
switch (c) {
@ -262,6 +265,7 @@ object_key_state:
break;
}
case '{': {
pj.write_tape(0, c); // strangely, moving this to object_begin slows things down
// we have not yet encountered } so we need to come back for it
pj.ret_address[depth] = &&object_continue;
// we found an object inside an object, so we need to increment the depth
@ -273,6 +277,7 @@ object_key_state:
goto object_begin;
}
case '[': {
pj.write_tape(0, c); // strangely, moving this to array_begin slows things down
// we have not yet encountered } so we need to come back for it
pj.ret_address[depth] = &&object_continue;
// we found an array inside an object, so we need to increment the depth
@ -321,7 +326,6 @@ scope_end:
array_begin:
DEBUG_PRINTF("in array_begin\n");
pj.containing_scope_offset[depth] = pj.get_current_loc();
pj.write_tape(0, c);
UPDATE_CHAR();
if (c == ']') {
goto scope_end; // could also go to array_continue
@ -384,8 +388,8 @@ main_array_switch:
}
case '{': {
// we have not yet encountered ] so we need to come back for it
pj.write_tape(0, c); // strangely, moving this to object_begin slows things down
pj.ret_address[depth] = &&array_continue;
// we found an object inside an array, so we need to increment the depth
depth++;
if (depth > pj.depthcapacity) {
@ -396,14 +400,13 @@ main_array_switch:
}
case '[': {
// we have not yet encountered ] so we need to come back for it
pj.write_tape(0, c); // strangely, moving this to array_begin slows things down
pj.ret_address[depth] = &&array_continue;
// we found an array inside an array, so we need to increment the depth
depth++;
if (depth > pj.depthcapacity) {
goto fail;
}
goto array_begin;
}
default: