PeppaPEG version: 1.2.0.
Given program, half of the execution time spent on NeedLoosen. We should optimize it.
$ cat examples/json.c
#include <stdio.h>
#include <stdlib.h>
#include "../peppapeg.h"
#include "json.h"
# define NESTING_DEPTH 1000
int main(int argc, char* argv[]) {
char* input = malloc(sizeof(char) * (NESTING_DEPTH*2 + 1));
int i;
for (i = 0; i < NESTING_DEPTH; i++) {
input[i] = '[';
input[NESTING_DEPTH+i] = ']';
}
input[NESTING_DEPTH*2] = '\0';
P4_Grammar* grammar = P4_CreateJSONGrammar();
P4_Source* source = P4_CreateSource(input, P4_JSONEntry);
printf("%u\n", P4_Parse(grammar, source));
free(input);
P4_DeleteSource(source);
P4_DeleteGrammar(grammar);
return 0;
}--------------------------------------------------------------------------------
Ir
--------------------------------------------------------------------------------
1,265,470,759 (100.0%) PROGRAM TOTALS
--------------------------------------------------------------------------------
Ir file:function
--------------------------------------------------------------------------------
706,187,168 (55.80%) peppapeg.c:P4_NeedLoosen [/app/a.out]
320,620,450 (25.34%) peppapeg.c:P4_IsTight [/app/a.out]
170,320,160 (13.46%) peppapeg.c:P4_IsScoped [/app/a.out]
25,020,000 ( 1.98%) peppapeg.c:P4_NeedSquash [/app/a.out]
10,000,000 ( 0.79%) peppapeg.c:P4_IsSquashed [/app/a.out]
4,617,160 ( 0.36%) ???:_int_free [/usr/lib64/libc-2.28.so]
3,382,226 ( 0.27%) ???:malloc [/usr/lib64/ld-2.28.so]
2,727,160 ( 0.22%) peppapeg.c:P4_Match'2 [/app/a.out]
1,925,056 ( 0.15%) ???:__strlen_avx2 [/usr/lib64/libc-2.28.so]
1,848,485 ( 0.15%) ???:free [/usr/lib64/ld-2.28.so]
1,841,351 ( 0.15%) peppapeg.c:P4_MatchLiteral [/app/a.out]
1,705,988 ( 0.13%) peppapeg.c:P4_MatchChoice'2 [/app/a.out]
1,540,594 ( 0.12%) peppapeg.c:P4_IsRule [/app/a.out]
1,518,598 ( 0.12%) peppapeg.c:P4_Expression_dispatch'2 [/app/a.out]
$ time ./a.out
real 0m0.157s
user 0m0.154s
sys 0m0.002s
PeppaPEG version: 1.2.0.
Given program, half of the execution time spent on NeedLoosen. We should optimize it.
Run it with valgrind:
$ gcc -g peppapeg.c examples/json.c && valgrind --tool=callgrind ./a.out $ callgrind_annotate callgrind.out.63642We have below profiling result:
A full profiling result can be seen here: https://gist.github.com/soasme/38471063511aa14302e5ccad173767de