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// LICM Phase A 回归覆盖:
// loop_invariant_global — 全局只读 → 应被外提
// loop_writes_self — 循环内写自己 → 不应外提
// loop_writes_other — 循环内写"别处"的全局 → 应外提(no alias)
// loop_with_call — 循环内有 call → 不应外提
// nested_loops — 嵌套循环,外层不变 / 内层与外层 IV 共动
// array_index_dep — 循环内对数组下标 store,可能 alias 同数组的 load → 不外提
int g_const = 13;
int g_other = 100;
int g_writes = 5;
int arr[16];
int loop_invariant_global(int n) {
int s = 0;
int i = 0;
while (i < n) {
s = s + g_const;
i = i + 1;
}
return s;
}
int loop_writes_self(int n) {
int s = 0;
int i = 0;
while (i < n) {
s = s + g_writes;
g_writes = g_writes + 2;
i = i + 1;
}
return s;
}
int loop_writes_other(int n) {
int s = 0;
int i = 0;
while (i < n) {
s = s + g_const;
g_other = g_other + 1;
i = i + 1;
}
return s;
}
int leaf(int x) {
return x + 1;
}
int loop_with_call(int n) {
int s = 0;
int i = 0;
while (i < n) {
s = s + g_const + leaf(i);
i = i + 1;
}
return s;
}
int nested_loops(int n) {
int s = 0;
int i = 0;
while (i < n) {
int j = 0;
while (j < n) {
s = s + g_const;
j = j + 1;
}
i = i + 1;
}
return s;
}
int array_index_dep(int n) {
int s = 0;
int i = 0;
while (i < n) {
arr[i] = g_const;
s = s + arr[0];
i = i + 1;
}
return s;
}
int main() {
putint(loop_invariant_global(10)); putch(10); // 130
putint(loop_writes_self(4)); putch(10); // 5+7+9+11=32
putint(g_writes); putch(10); // 13
putint(loop_writes_other(5)); putch(10); // 65
putint(g_other); putch(10); // 105
putint(loop_with_call(4)); putch(10); // (13+1)+(13+2)+(13+3)+(13+4)=62
putint(nested_loops(5)); putch(10); // 13*25=325
putint(array_index_dep(3)); putch(10); // arr[0]=13 全程, s=13+13+13=39
return 0;
}
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