diff options
Diffstat (limited to 'py/qstr.c')
| -rw-r--r-- | py/qstr.c | 41 |
1 files changed, 40 insertions, 1 deletions
@@ -92,6 +92,7 @@ STATIC const qstr_pool_t const_pool = { void qstr_init(void) { MP_STATE_VM(last_pool) = (qstr_pool_t*)&const_pool; // we won't modify the const_pool since it has no allocated room left + MP_STATE_VM(qstr_last_chunk) = NULL; } STATIC const byte *find_qstr(qstr q) { @@ -152,8 +153,46 @@ qstr qstr_from_strn(const char *str, mp_uint_t len) { assert(len < (1 << (8 * MICROPY_QSTR_BYTES_IN_LEN))); qstr q = qstr_find_strn(str, len); if (q == 0) { + // qstr does not exist in interned pool so need to add it + + // compute number of bytes needed to intern this string + mp_uint_t n_bytes = 2 + MICROPY_QSTR_BYTES_IN_LEN + len + 1; + + if (MP_STATE_VM(qstr_last_chunk) != NULL && MP_STATE_VM(qstr_last_used) + n_bytes > MP_STATE_VM(qstr_last_alloc)) { + // not enough room at end of previously interned string so try to grow + byte *new_p = m_renew_maybe(byte, MP_STATE_VM(qstr_last_chunk), MP_STATE_VM(qstr_last_alloc), MP_STATE_VM(qstr_last_alloc) + n_bytes, false); + if (new_p == NULL) { + // could not grow existing memory; shrink it to fit previous + (void)m_renew(byte, MP_STATE_VM(qstr_last_chunk), MP_STATE_VM(qstr_last_alloc), MP_STATE_VM(qstr_last_used)); + MP_STATE_VM(qstr_last_chunk) = NULL; + } else { + // could grow existing memory + MP_STATE_VM(qstr_last_alloc) += n_bytes; + } + } + + if (MP_STATE_VM(qstr_last_chunk) == NULL) { + // no existing memory for the interned string so allocate a new chunk + mp_uint_t al = n_bytes; + if (al < MICROPY_ALLOC_QSTR_CHUNK_INIT) { + al = MICROPY_ALLOC_QSTR_CHUNK_INIT; + } + MP_STATE_VM(qstr_last_chunk) = m_new_maybe(byte, al); + if (MP_STATE_VM(qstr_last_chunk) == NULL) { + // failed to allocate a large chunk so try with exact size + MP_STATE_VM(qstr_last_chunk) = m_new(byte, n_bytes); + al = n_bytes; + } + MP_STATE_VM(qstr_last_alloc) = al; + MP_STATE_VM(qstr_last_used) = 0; + } + + // allocate memory from the chunk for this new interned string's data + byte *q_ptr = MP_STATE_VM(qstr_last_chunk) + MP_STATE_VM(qstr_last_used); + MP_STATE_VM(qstr_last_used) += n_bytes; + + // store the interned strings' data mp_uint_t hash = qstr_compute_hash((const byte*)str, len); - byte *q_ptr = m_new(byte, 2 + MICROPY_QSTR_BYTES_IN_LEN + len + 1); q_ptr[0] = hash; q_ptr[1] = hash >> 8; Q_SET_LENGTH(q_ptr, len); |