}
void raw_svector_ostream::write_impl(const char *Ptr, size_t Size) {
- // If we're writing bytes from the end of the buffer into the smallvector, we
- // don't need to copy the bytes, just commit the bytes because they are
- // already in the right place.
- if (Ptr == OS.end()) {
- assert(OS.size() + Size <= OS.capacity() && "Invalid write_impl() call!");
- OS.set_size(OS.size() + Size);
+ size_t NewSize = OS.size() + Size;
+ size_t NewReservation = NewSize + 64;
+
+ bool NoOverlap = Ptr + Size < OS.begin() || Ptr > OS.begin() + OS.capacity();
+
+ if (NoOverlap) {
+ assert(!GetNumBytesInBuffer());
+ OS.reserve(NewReservation);
+ memcpy(OS.end(), Ptr, Size);
+ OS.set_size(NewSize);
+ } else if (Ptr == OS.end()) {
+ // Grow the buffer to include the scratch area without copying.
+ assert(NewSize <= OS.capacity() && "Invalid write_impl() call!");
+ OS.set_size(NewSize);
+ OS.reserve(NewReservation);
} else {
- assert(GetNumBytesInBuffer() == 0 &&
- "Should be writing from buffer if some bytes in it");
- // Otherwise, do copy the bytes.
- OS.append(Ptr, Ptr+Size);
+ OS.append(Ptr, Ptr + Size);
+ OS.reserve(NewReservation);
}
- // Grow the vector if necessary.
- if (OS.capacity() - OS.size() < 64)
- OS.reserve(OS.capacity() * 2);
-
- // Update the buffer position.
SetBuffer(OS.end(), OS.capacity() - OS.size());
}