当我在命令行中使用此命令运行它时，我的缓存模拟器文件会生成分段错误错误：
./csim.c -s 1 -E 1 -b 1 -t traces/yi2.trace.
我不熟悉分段错误错误。
任何帮助将不胜感激。
编辑：使用gdb找到这个
Program received signal SIGSEGV, Segmentation fault.
strcmp () at ../sysdeps/x86_64/multiarch/../strcmp.S:132
132 ../sysdeps/x86_64/multiarch/../strcmp.S: No such file or directory.
(gdb) bt
#0 strcmp () at ../sysdeps/x86_64/multiarch/../strcmp.S:132
#1 0x00007ffff7deb1a5 in _dl_name_match_p (name=0x400459 "libm.so.6",
map=0x7ffff7ffe1c8) at dl-misc.c:289
#2 0x00007ffff7de402f in do_lookup_x (new_hash=new_hash@entry=193502747,
old_hash=old_hash@entry=0x7fffffffe200,
result=result@entry=0x7fffffffe210, scope=<optimized out>,
i=<optimized out>, i@entry=0, flags=flags@entry=1, skip=skip@entry=0x0,
undef_map=undef_map@entry=0x7ffff7ffe1c8) at dl-lookup.c:462
#3 0x00007ffff7de4961 in _dl_lookup_symbol_x (undef_name=0x4004bc "pow",
undef_map=0x7ffff7ffe1c8, ref=ref@entry=0x7fffffffe2c8,
symbol_scope=0x7ffff7ffe520, version=0x7ffff7ff7f58,
type_class=type_class@entry=1, flags=1, skip_map=skip_map@entry=0x0)
at dl-lookup.c:737
#4 0x00007ffff7de9527 in _dl_fixup (l=<optimized out>,
reloc_arg=<optimized out>) at ../elf/dl-runtime.c:111
#5 0x00007ffff7df04d5 in _dl_runtime_resolve ()
at ../sysdeps/x86_64/dl-trampoline.S:45
#6 0x000000000040109d in main (argc=9, argv=0x7fffffffe4c8) at csim.c:497
代码：
#include <stdlib.h>
#include <stdio.h>
#include <getopt.h>
#include <strings.h>
#include <unistd.h>
#include <math.h>
#include "cachelab.h"
typedef struct lines{
short int valid;
long long int tag;
char block;
int last, n_accesses;
} line;
typedef struct sets{
line *set_line;
} set;
typedef struct caches{
set *cache_set;
} cache;
typedef struct cache_evaluations{
int hits, misses, evictions;
} evaluation;
typedef struct HME{
evaluation *eval;
} hme;
typedef struct data_reads{
int s, E, b, n_sets, n_lines;
} data;
int verbosity;
void help(){
printf("Usage: [-hv] -s <num> -E <num> -b <num> -t <file>\n\n");
printf(" -h Help message.\n");
printf(" -v Verbose flag (optional).\n");
printf(" -s <num> Number of set index bits.\n");
printf(" -E <num> Number of lines per set.\n");
printf(" -b <num> Number of block offset bits.\n");
printf(" -t <file> Trace file.\n");
exit(0);
}
void create_cache(cache c_cache, data r_data){
set c_set;
line c_line;
int n_sets = r_data.n_sets;
int n_lines = r_data.n_lines;
int set_i, line_j;
c_cache.cache_set = (set *) (malloc(sizeof(set) * n_sets));
for(set_i = 0; set_i < n_sets; set_i += 1){
c_set.set_line = (line *) (malloc(sizeof(line) * n_lines));
c_cache.cache_set[set_i] = c_set;
for(line_j = 0; line_j < n_lines; line_j += 1){
c_line.valid = 0;
c_line.tag = 0;
c_line.n_accesses = 0;
c_line.last = 0;
c_set.set_line[line_j] = c_line;
}
}
}
void empty_cache(cache c_cache, data r_data){
set set_ptr;
int n_sets = r_data.n_sets;
int set_i;
for(set_i = 0; set_i < n_sets; set_i += 1){
set_ptr = c_cache.cache_set[set_i];
if(set_ptr.set_line != NULL)
free(set_ptr.set_line);
}
}
int find_lru(set tmp_set, data r_data){
int min_count = tmp_set.set_line[0].n_accesses;
int n_lines = r_data.n_lines;
int line_j;
for(line_j = 0; line_j < n_lines; line_j += 1){
if(tmp_set.set_line[line_j].n_accesses < min_count){
min_count = tmp_set.set_line[line_j].n_accesses;
}
}
for(line_j = 0; line_j < n_lines; line_j += 1){
if(tmp_set.set_line[line_j].n_accesses != min_count){
tmp_set.set_line[line_j].n_accesses += 1;
}
}
return min_count;
}
int eviction(set tmp_set, data r_data){
int lru = find_lru(tmp_set, r_data);
int n_lines = r_data.n_lines;
int evict_idx;
int line_n;
for(line_n = 0; line_n < n_lines; line_n += 1){
if((tmp_set.set_line[line_n].last == 0) && tmp_set.set_line[line_n].n_accesses == lru){
tmp_set.set_line[line_n].valid = 0;
tmp_set.set_line[line_n].tag = 0;
tmp_set.set_line[line_n].n_accesses = 0;
tmp_set.set_line[line_n].last = 0;
evict_idx = line_n;
break;
}
tmp_set.set_line[line_n].n_accesses += 1;
}
return evict_idx;
}
int find_line(set tmp_set, data r_data, hme c_hme){
short int cont = 1;
int n_lines = r_data.n_lines;
int line_idx;
int line_n;
for(line_n = 0; line_n < n_lines; line_n += 1){
tmp_set.set_line[line_n].n_accesses += 1;
if(!(tmp_set.set_line[line_n].valid)){
cont = 0;
line_idx = line_n;
break;
}
}
if(cont){
c_hme.eval[0].evictions += 1;
line_idx = eviction(tmp_set, r_data);
}
return line_idx;
}
int mask(int b){
int masked_b = pow(2.0,b) - 1;
return masked_b;
}
void cache_sim(cache c_cache, hme c_hme, data r_data, unsigned long long int address){
int n_lines = r_data.n_lines;
unsigned long long int n_tag = address >> (r_data.s + r_data.b);
int set_index = (address >> r_data.b) & mask(r_data.s);
set tmp_set = c_cache.cache_set[set_index];
int block_offset = address & mask(r_data.b);
char n_block = (char) block_offset;
int hit = 0;
int line_j;
for (line_j = 0; line_j < n_lines; line_j += 1){
tmp_set.set_line[line_j].n_accesses += 1;
tmp_set.set_line[line_j].last = 0;
if(tmp_set.set_line[line_j].valid && tmp_set.set_line[line_j].tag == n_tag){
tmp_set.set_line[line_j].last = 1;
hit = 1;
break;
}
}
if(hit)
c_hme.eval[0].hits += 1;
else{
c_hme.eval[0].misses += 1;
int line_n = find_line(tmp_set, r_data, c_hme);
tmp_set.set_line[line_n].valid = 1;
tmp_set.set_line[line_n].tag = n_tag;
tmp_set.set_line[line_n].block = n_block;
tmp_set.set_line[line_n].last = 1;
tmp_set.set_line[line_n].n_accesses += 1;
}
}
int main(int argc, char **argv){
char cl_arg, *tracefile;
data r_data = {0};
while((cl_arg = getopt(argc,argv,"hv:s:E:b:t")) != -1){
switch(cl_arg){
case 'h':
help();
case 'v':
verbosity = 1;
break;
case 's':
r_data.s = atoi(optarg);
break;
case 'E':
r_data.E = atoi(optarg);
break;
case 'b':
r_data.b = atoi(optarg);
break;
case 't':
tracefile = optarg;
break;
default:
help();
exit(1);
}
}
cache c_cache;
evaluation c_eval;
c_eval.hits = 0;
c_eval.misses = 0;
c_eval.evictions = 0;
hme c_hme;
c_hme.eval[0] = c_eval;
r_data.n_sets = pow(2, r_data.s);
r_data.n_lines = r_data.E;
create_cache(c_cache, r_data);
unsigned long long int address;
char instr;
int size;
FILE *file;
file = fopen(tracefile,"r");
if (file != NULL){
while (fscanf(file, " %c %llx,%d", &instr, &address, &size) == 3){
switch(instr){
case 'L':
cache_sim(c_cache, c_hme, r_data, address);
break;
case 'S':
cache_sim(c_cache, c_hme, r_data, address);
break;
case 'M':
cache_sim(c_cache, c_hme, r_data, address);
cache_sim(c_cache, c_hme, r_data, address);
break;
default:
break;
}
}
}
printSummary(c_hme.eval[0].hits, c_hme.eval[0].misses, c_hme.eval[0].evictions);
empty_cache(c_cache, r_data);
fclose(file);
return 0;
}
答案 0 :(得分：0)
您正在使用结构的值调用（ void ...）函数。 调用者（main（））看到的结构不会改变;只有本地副本。示例（使用int结构成员而不是指针）：
void (D1::*)()结果：
void (D12::*)()更新：与（最小化）原始程序相同：
#include <stdio.h>
typedef struct {
int val;
} omg;
void wtf(omg this);
/* function to change the value of this ??? */
void wtf(omg this)
{
this.val = 42;
}
/* let's call it ... */
int main(void) {
omg jesus = {0};
wtf( jesus);
printf("%d\n", jesus.val);
return 0;
}
结果：
plasser@pisbak:$ cc -Wall omg.c
plasser@pisbak:$ ./a.out
0
plasser@pisbak:$
答案 1 :(得分：-1)
我的逐出功能正在为一条线路中的一条线路返回一个无效索引（令人遗憾）。另外，我错误地访问了一些成员（使用 - ＆gt;而不是。）。