我有C代码：
int edges_start[3000];
int edges_end[3000];
float edges_len[3000];
int g_links_id[1000][100];
float g_links_weight[1000][100];
int cache_id[1000];
float cache_distance[1000];
int cache_prev[1000];
int cache_links_id[1000][100];
float cache_links_weight[1000][100];
int queue_id[1000];
float queue_distance[1000];
int queue_prev[1000];
int queue_links_id[1000][100];
float queue_links_weight[1000][100];
void* memcpy(char* dst, char* src, int count) {
while(count--) *dst++ = *src++;
}
void init_cpp() {
for (int i=0; i < 1000; i++) {
cache_id[i] = -2;
queue_id[i] = -2;
cache_distance[i] = 100000;
queue_distance[i] = 100000;
cache_prev[i] = -2;
queue_prev[i] = -2;
for (int j=0; j < 100; j++) {
queue_links_id[i][j] = -2;
queue_links_weight[i][j] = 100000;
cache_links_id[i][j] = -2;
cache_links_weight[i][j] = 100000;
}
}
}
void init_edges_cpp() {
for (int i=0; i < 3000; i++) {
edges_start[i] = -2;
edges_end[i] = -2;
edges_len[i] = -2.0;
}
for (int i=0; i < 1000; i++) {
for (int j=0; j < 100; j++) {
g_links_id[i][j] = -2;
g_links_weight[i][j] = -2.0;
}
}
}
void add_edge_cpp(int index, int start, int end, float len) {
edges_start[index] = start;
edges_end[index] = end;
edges_len[index] = len;
}
void fill_graph_cpp() {
for (int i=0; i < 3000; i++) {
int s = edges_start[i];
int e = edges_end[i];
float len = edges_len[i];
if (s == -2) {
break;
}
int links_len = 0;
for (int j=0; j < 100; j++) {
if (g_links_id[s][j] == -2) {
links_len = j;
break;
}
}
g_links_id[s][links_len] = e;
g_links_weight[s][links_len] = len;
for (int j=0; j < 100; j++) {
if (g_links_id[e][j] == -2) {
links_len = j;
break;
}
}
g_links_id[e][links_len] = s;
g_links_weight[e][links_len] = len;
}
}
void get_dists_cpp(int a, int L) {
int i = L;
while (--i >= 0) {
for (int j = 0; j < 100; j++) {
//console.log()
if (g_links_id[i][j] == -2) {
break;
}
cache_links_id[i][j] = g_links_id[i][j];
cache_links_weight[i][j] = g_links_weight[i][j];
}
cache_id[i] = i;
}
queue_id[0] = cache_id[a];
cache_distance[a] = 0;
queue_distance[0] = cache_distance[a];
queue_prev[0] = queue_prev[a];
for (int j=0; j < 100; j++) {
queue_links_id[0][j] = cache_links_id[a][j];
queue_links_weight[0][j] = cache_links_weight[a][j];
}
i=0;
int queue_len = 1;
while (i < queue_len) {
int node_id = queue_id[i];
float node_distance = queue_distance[i];
int node_prev = queue_prev[i];
int j=0;
for (int k=0; k < 100; k++) {
if (queue_links_id[i][k] == -2) {
j=k;
break;
}
}
while (--j >= 0) {
int link_id = queue_links_id[i][j];
float link_weight = queue_links_weight[i][j];
int c_id = cache_id[link_id];
float c_distance = cache_distance[link_id];
int c_prev = cache_prev[link_id];
float d = node_distance + link_weight;
if (d < c_distance) {
cache_prev[link_id] = node_id;
cache_distance[link_id] = d;
int last_ind = queue_len;
queue_id[last_ind] = cache_id[link_id];
queue_distance[last_ind] = cache_distance[link_id];
for (int k=0; k < 100; k++) {
if (cache_links_id[link_id][k] == -2) {
break;
}
queue_links_id[last_ind][k] = cache_links_id[link_id][k];
queue_links_weight[last_ind][k] = cache_links_weight[link_id][k];
}
queue_prev[last_ind] = cache_prev[link_id];
queue_len++;
}
}
i++;
}
}
int get_edges_start(int index) {
return edges_start[index];
}
float get_cache_distance(int index) {
return cache_distance[index];
}
int get_cache_prev(int index) {
return cache_prev[index];
}
int main() {
init_edges_cpp();
init_cpp();
add_edge_cpp(0, 0, 2, 1);
add_edge_cpp(1, 0, 1, 1);
add_edge_cpp(2, 1, 2, 1);
add_edge_cpp(3, 2, 3, 1);
add_edge_cpp(4, 2, 4, 1);
add_edge_cpp(5, 3, 4, 1);
fill_graph_cpp();
get_dists_cpp(0, 5);
/*
for (int i=0; i < 10; i++) {
cout << i << " " << get_cache_distance(i) << " " << get_cache_prev(i) << endl;
}
*/
return 0;
}
它工作正常，你可以在这里检查
但是，当我试图用这个网站把它编译成wasm时
我在左栏中输入了以下代码：https://pastebin.com/NG10Z0jX
在右边的字段中，js代码：
var wasmModule = new WebAssembly.Module(wasmCode);
var wasmInstance = new WebAssembly.Instance(wasmModule, wasmImports);
var wasm_module = wasmInstance.exports
wasm_module.main();
for (var i=0; i < 5; i++) {
var c1 = wasm_module.get_cache_distance(i);
var c2 = wasm_module.get_cache_prev(i);
log(i+" " +c1 + " " + c2)
}
它返回错误的输出：
vert: 0 dist: 0 prev -2
vert: 1 dist: 100000 prev -2
vert: 2 dist: 100000 prev -2
vert: 3 dist: 100000 prev -2
vert: 4 dist: 100000 prev -2
它应该返回这个：
vert: 0 dist: 0.000000 prev: -2
vert: 1 dist: 1.000000 prev: 0
vert: 2 dist: 1.000000 prev: 0
vert: 3 dist: 2.000000 prev: 2
vert: 4 dist: 2.000000 prev: 2
如何将此C代码正确编译到WebAssembly
答案是将其放入C代码中：
void* memcpy(char* dst, char* src, int count) {
void* p=dst;
while(count--) *dst++ = *src++;
return p;
}