Merge pull request #92546 from AThousandShips/faster_replace

[Core] Optimize `String::replace` methods
This commit is contained in:
Rémi Verschelde 2024-08-19 12:08:45 +02:00
commit 4afcbb1c8b
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1 changed files with 159 additions and 62 deletions

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@ -4032,54 +4032,161 @@ String String::format(const Variant &values, const String &placeholder) const {
return new_string; return new_string;
} }
String String::replace(const String &p_key, const String &p_with) const { static String _replace_common(const String &p_this, const String &p_key, const String &p_with, bool p_case_insensitive) {
String new_string; if (p_key.is_empty() || p_this.is_empty()) {
return p_this;
}
const int key_length = p_key.length();
int search_from = 0; int search_from = 0;
int result = 0; int result = 0;
while ((result = find(p_key, search_from)) >= 0) { LocalVector<int> found;
new_string += substr(search_from, result - search_from);
new_string += p_with; while ((result = (p_case_insensitive ? p_this.findn(p_key, search_from) : p_this.find(p_key, search_from))) >= 0) {
search_from = result + p_key.length(); found.push_back(result);
search_from = result + key_length;
} }
if (search_from == 0) { if (found.is_empty()) {
return *this; return p_this;
} }
new_string += substr(search_from, length() - search_from); String new_string;
const int with_length = p_with.length();
const int old_length = p_this.length();
new_string.resize(old_length + found.size() * (with_length - key_length) + 1);
char32_t *new_ptrw = new_string.ptrw();
const char32_t *old_ptr = p_this.ptr();
const char32_t *with_ptr = p_with.ptr();
int last_pos = 0;
for (const int &pos : found) {
if (last_pos != pos) {
memcpy(new_ptrw, old_ptr + last_pos, (pos - last_pos) * sizeof(char32_t));
new_ptrw += (pos - last_pos);
}
if (with_length) {
memcpy(new_ptrw, with_ptr, with_length * sizeof(char32_t));
new_ptrw += with_length;
}
last_pos = pos + key_length;
}
if (last_pos != old_length) {
memcpy(new_ptrw, old_ptr + last_pos, (old_length - last_pos) * sizeof(char32_t));
new_ptrw += old_length - last_pos;
}
*new_ptrw = 0;
return new_string; return new_string;
} }
String String::replace(const char *p_key, const char *p_with) const { static String _replace_common(const String &p_this, char const *p_key, char const *p_with, bool p_case_insensitive) {
String new_string; int key_length = strlen(p_key);
if (key_length == 0 || p_this.is_empty()) {
return p_this;
}
int search_from = 0; int search_from = 0;
int result = 0; int result = 0;
while ((result = find(p_key, search_from)) >= 0) { LocalVector<int> found;
new_string += substr(search_from, result - search_from);
new_string += p_with; while ((result = (p_case_insensitive ? p_this.findn(p_key, search_from) : p_this.find(p_key, search_from))) >= 0) {
int k = 0; found.push_back(result);
while (p_key[k] != '\0') { search_from = result + key_length;
k++; }
if (found.is_empty()) {
return p_this;
}
String new_string;
// Create string to speed up copying as we can't do `memcopy` between `char32_t` and `char`.
const String with_string(p_with);
const int with_length = with_string.length();
const int old_length = p_this.length();
new_string.resize(old_length + found.size() * (with_length - key_length) + 1);
char32_t *new_ptrw = new_string.ptrw();
const char32_t *old_ptr = p_this.ptr();
const char32_t *with_ptr = with_string.ptr();
int last_pos = 0;
for (const int &pos : found) {
if (last_pos != pos) {
memcpy(new_ptrw, old_ptr + last_pos, (pos - last_pos) * sizeof(char32_t));
new_ptrw += (pos - last_pos);
} }
search_from = result + k; if (with_length) {
memcpy(new_ptrw, with_ptr, with_length * sizeof(char32_t));
new_ptrw += with_length;
}
last_pos = pos + key_length;
} }
if (search_from == 0) { if (last_pos != old_length) {
return *this; memcpy(new_ptrw, old_ptr + last_pos, (old_length - last_pos) * sizeof(char32_t));
new_ptrw += old_length - last_pos;
} }
new_string += substr(search_from, length() - search_from); *new_ptrw = 0;
return new_string; return new_string;
} }
String String::replace(const String &p_key, const String &p_with) const {
return _replace_common(*this, p_key, p_with, false);
}
String String::replace(const char *p_key, const char *p_with) const {
return _replace_common(*this, p_key, p_with, false);
}
String String::replace_first(const String &p_key, const String &p_with) const { String String::replace_first(const String &p_key, const String &p_with) const {
int pos = find(p_key); int pos = find(p_key);
if (pos >= 0) { if (pos >= 0) {
return substr(0, pos) + p_with + substr(pos + p_key.length(), length()); const int old_length = length();
const int key_length = p_key.length();
const int with_length = p_with.length();
String new_string;
new_string.resize(old_length + (with_length - key_length) + 1);
char32_t *new_ptrw = new_string.ptrw();
const char32_t *old_ptr = ptr();
const char32_t *with_ptr = p_with.ptr();
if (pos > 0) {
memcpy(new_ptrw, old_ptr, pos * sizeof(char32_t));
new_ptrw += pos;
}
if (with_length) {
memcpy(new_ptrw, with_ptr, with_length * sizeof(char32_t));
new_ptrw += with_length;
}
pos += key_length;
if (pos != old_length) {
memcpy(new_ptrw, old_ptr + pos, (old_length - pos) * sizeof(char32_t));
new_ptrw += (old_length - pos);
}
*new_ptrw = 0;
return new_string;
} }
return *this; return *this;
@ -4088,55 +4195,45 @@ String String::replace_first(const String &p_key, const String &p_with) const {
String String::replace_first(const char *p_key, const char *p_with) const { String String::replace_first(const char *p_key, const char *p_with) const {
int pos = find(p_key); int pos = find(p_key);
if (pos >= 0) { if (pos >= 0) {
int substring_length = strlen(p_key); const int old_length = length();
return substr(0, pos) + p_with + substr(pos + substring_length, length()); const int key_length = strlen(p_key);
const int with_length = strlen(p_with);
String new_string;
new_string.resize(old_length + (with_length - key_length) + 1);
char32_t *new_ptrw = new_string.ptrw();
const char32_t *old_ptr = ptr();
if (pos > 0) {
memcpy(new_ptrw, old_ptr, pos * sizeof(char32_t));
new_ptrw += pos;
}
for (int i = 0; i < with_length; ++i) {
*new_ptrw++ = p_with[i];
}
pos += key_length;
if (pos != old_length) {
memcpy(new_ptrw, old_ptr + pos, (old_length - pos) * sizeof(char32_t));
new_ptrw += (old_length - pos);
}
*new_ptrw = 0;
return new_string;
} }
return *this; return *this;
} }
String String::replacen(const String &p_key, const String &p_with) const { String String::replacen(const String &p_key, const String &p_with) const {
String new_string; return _replace_common(*this, p_key, p_with, true);
int search_from = 0;
int result = 0;
while ((result = findn(p_key, search_from)) >= 0) {
new_string += substr(search_from, result - search_from);
new_string += p_with;
search_from = result + p_key.length();
}
if (search_from == 0) {
return *this;
}
new_string += substr(search_from, length() - search_from);
return new_string;
} }
String String::replacen(const char *p_key, const char *p_with) const { String String::replacen(const char *p_key, const char *p_with) const {
String new_string; return _replace_common(*this, p_key, p_with, true);
int search_from = 0;
int result = 0;
int substring_length = strlen(p_key);
if (substring_length == 0) {
return *this; // there's nothing to match or substitute
}
while ((result = findn(p_key, search_from)) >= 0) {
new_string += substr(search_from, result - search_from);
new_string += p_with;
search_from = result + substring_length;
}
if (search_from == 0) {
return *this;
}
new_string += substr(search_from, length() - search_from);
return new_string;
} }
String String::repeat(int p_count) const { String String::repeat(int p_count) const {