Fix to escape VERILATOR_ROOT file paths (#3764) (#3765)

src/V3String.cpp

@@ -116,6 +116,19 @@ string VString::quoteStringLiteralForShell(const string& str) {
     return result;
 }
 
+string VString::escapeStringForPath(const string &str) {
+    if (str.find(R"(\\)") != string::npos) return str; // if it has been escaped already, don't do it again
+    if (str.find('/') != string::npos) return str; // can be replaced by `__MINGW32__` or `_WIN32`
+    string result;
+    const char space = ' '; // escape space like this `Program Files`
+    const char escape = '\\';
+    for (const char c: str) {
+        if (c == space || c == escape) result.push_back(escape);
+        result.push_back(c);
+    }
+    return result;
+}
+
 string VString::spaceUnprintable(const string& str) {
     string out;
     for (const char c : str) {