Hello @ all,
I successfully vectorized a simple loop:
```
bool func_is_vectorized (char*& cur, context& ctx) {
match_return r {cur, true};
constexpr char str1[] =
"aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa";
if (!(std::distance(r.pos, ctx.end) < 50)) {return false;}
for(int i = 0; i < 50; i += 1) {
if (str1[i] != r.pos[i]) { r.matched = false; }
}
if (r.matched) {
r.pos += 50;
}
return r.matched;
}
```
I wanted to remove the match_return structure and now the loop no
longer vectorizes. The message is:
not vectorized: relevant phi not supported: matched_21 = PHI <_20(6),
1(5)>
The "new" code is:
```
bool func_is_also_not_vectorized (char*& cur, context& ctx) {
bool matched = true;
constexpr char str1[] =
"aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa";
if (!(std::distance(cur, ctx.end) < 50)) {return false;}
for(int i = 0; i < 50; i += 1) {
if (str1[i] != cur[i]) { matched = false; }
}
if (matched) {
cur += 50;
}
return matched;
}
```
The interesting part is. If I only replace `r.matched` with `matched`
and introduce the proper variable. The vectorizer is already failing.
A reproducer on compiler explorer: https://godbolt.org/z/YEPzfx3eT
Am I doing something wrong? Is this a possible bug?
Cheers
Max
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