extmod, zlibd: Make some simple ROM and RAM savings.

ROM down by 320 bytes on stmhal.  RAM down by 5.5k for a decompression
object.

extmod/miniz/tinfl.c

@@ -94,10 +94,11 @@ typedef enum
 tinfl_status tinfl_decompress(tinfl_decompressor *r, const mz_uint8 *pIn_buf_next, size_t *pIn_buf_size, mz_uint8 *pOut_buf_start, mz_uint8 *pOut_buf_next, size_t *pOut_buf_size, const mz_uint32 decomp_flags);
 
 // Internal/private bits follow.
+// dpgeorge: TINFL_FAST_LOOKUP_BITS can be adjusted to trade off RAM usage against speed.
 enum
 {
   TINFL_MAX_HUFF_TABLES = 3, TINFL_MAX_HUFF_SYMBOLS_0 = 288, TINFL_MAX_HUFF_SYMBOLS_1 = 32, TINFL_MAX_HUFF_SYMBOLS_2 = 19,
-  TINFL_FAST_LOOKUP_BITS = 10, TINFL_FAST_LOOKUP_SIZE = 1 << TINFL_FAST_LOOKUP_BITS
+  TINFL_FAST_LOOKUP_BITS = 7, TINFL_FAST_LOOKUP_SIZE = 1 << TINFL_FAST_LOOKUP_BITS
 };
 
 typedef struct
@@ -228,12 +229,12 @@ struct tinfl_decompressor_tag
 
 tinfl_status tinfl_decompress(tinfl_decompressor *r, const mz_uint8 *pIn_buf_next, size_t *pIn_buf_size, mz_uint8 *pOut_buf_start, mz_uint8 *pOut_buf_next, size_t *pOut_buf_size, const mz_uint32 decomp_flags)
 {
-  static const int s_length_base[31] = { 3,4,5,6,7,8,9,10,11,13, 15,17,19,23,27,31,35,43,51,59, 67,83,99,115,131,163,195,227,258,0,0 };
-  static const int s_length_extra[31]= { 0,0,0,0,0,0,0,0,1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,0,0,0 };
-  static const int s_dist_base[32] = { 1,2,3,4,5,7,9,13,17,25,33,49,65,97,129,193, 257,385,513,769,1025,1537,2049,3073,4097,6145,8193,12289,16385,24577,0,0};
-  static const int s_dist_extra[32] = { 0,0,0,0,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13};
+  static const mz_uint16 s_length_base[31] = { 3,4,5,6,7,8,9,10,11,13, 15,17,19,23,27,31,35,43,51,59, 67,83,99,115,131,163,195,227,258,0,0 };
+  static const mz_uint8 s_length_extra[31]= { 0,0,0,0,0,0,0,0,1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,0,0,0 };
+  static const mz_uint16 s_dist_base[32] = { 1,2,3,4,5,7,9,13,17,25,33,49,65,97,129,193, 257,385,513,769,1025,1537,2049,3073,4097,6145,8193,12289,16385,24577,0,0};
+  static const mz_uint8 s_dist_extra[32] = { 0,0,0,0,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13};
   static const mz_uint8 s_length_dezigzag[19] = { 16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15 };
-  static const int s_min_table_sizes[3] = { 257, 1, 4 };
+  static const mz_uint16 s_min_table_sizes[3] = { 257, 1, 4 };
 
   tinfl_status status = TINFL_STATUS_FAILED; mz_uint32 num_bits, dist, counter, num_extra; tinfl_bit_buf_t bit_buf;
   const mz_uint8 *pIn_buf_cur = pIn_buf_next, *const pIn_buf_end = pIn_buf_next + *pIn_buf_size;
@@ -498,6 +499,7 @@ common_exit:
   return status;
 }
 
+#if 0
 // Higher level helper functions.
 void *tinfl_decompress_mem_to_heap(const void *pSrc_buf, size_t src_buf_len, size_t *pOut_len, int flags)
 {
@@ -561,6 +563,7 @@ int tinfl_decompress_mem_to_callback(const void *pIn_buf, size_t *pIn_buf_size,
   *pIn_buf_size = in_buf_ofs;
   return result;
 }
+#endif
 
 #endif // #ifndef TINFL_HEADER_FILE_ONLY
 

extmod/modzlibd.c

@@ -53,7 +53,7 @@ STATIC mp_obj_t mod_zlibd_decompress(uint n_args, mp_obj_t *args) {
     mp_get_buffer_raise(data, &bufinfo, MP_BUFFER_READ);
     tinfl_decompressor *decomp = m_new_obj(tinfl_decompressor);
     tinfl_init(decomp);
-    DEBUG_printf("sizeof(tinfl_decompressor)=%d\n", sizeof(tinfl_decompressor));
+    DEBUG_printf("sizeof(tinfl_decompressor)=" UINT_FMT "\n", sizeof(tinfl_decompressor));
 
     byte *out = m_new(byte, bufinfo.len);
     size_t out_len = bufinfo.len;