Merge pull request #1586 from pguyot/w11/optimize-atoms

Add support for atoms longer than 255 bytes (but less than 256 chars)

See #1536

These changes are made under both the "Apache 2.0" and the "GNU Lesser General
Public License 2.1 or later" license terms (dual license).

SPDX-License-Identifier: Apache-2.0 OR LGPL-2.1-or-later

Author: bettio

src/libAtomVM/CMakeLists.txt

@@ -23,7 +23,6 @@ project (libAtomVM)
 
 set(HEADER_FILES
     atom.h
-    atomshashtable.h
     atom_table.h
     avmpack.h
     bif.h
@@ -75,7 +74,6 @@ set(HEADER_FILES
 
 set(SOURCE_FILES
     atom.c
-    atomshashtable.c
     atom_table.c
     avmpack.c
     bif.c

src/libAtomVM/atom.c

@@ -87,19 +87,17 @@ static void utoa10(unsigned int int_value, char *integer_string)
     integer_string[integer_string_len] = '\0';
 }
 
-void atom_write_mfa(char *buf, size_t buf_size, AtomString module, AtomString function, unsigned int arity)
+void atom_write_mfa(char *buf, size_t buf_size, size_t module_name_len, const void *module_data, size_t function_name_len, const void *function_data, unsigned int arity)
 {
-    size_t module_name_len = atom_string_len(module);
-    memcpy(buf, atom_string_data(module), module_name_len);
+    memcpy(buf, module_data, module_name_len);
 
     buf[module_name_len] = ':';
 
-    size_t function_name_len = atom_string_len(function);
     if (UNLIKELY((module_name_len + 1 + function_name_len + 1 + 4 + 1 > buf_size))) {
         fprintf(stderr, "Insufficient room to write mfa.\n");
         AVM_ABORT();
     }
-    memcpy(buf + module_name_len + 1, atom_string_data(function), function_name_len);
+    memcpy(buf + module_name_len + 1, function_data, function_name_len);
 
     buf[module_name_len + function_name_len + 1] = '/';
     utoa10(arity, buf + module_name_len + 1 + function_name_len + 1);

src/libAtomVM/atom.h

@@ -45,6 +45,7 @@ extern "C" {
 #define ATOM_STR(LENSTR, STR) (LENSTR STR)
 
 typedef const void *AtomString;
+typedef uint32_t atom_index_t;
 
 /**
  * @brief Gets a C string from an AtomString
@@ -98,11 +99,13 @@ static inline const void *atom_string_data(AtomString atom_str)
  *          buffer size.
  * @param   buf the buffer to write into
  * @param   buf_size the amount of room in the buffer
- * @param   module the module name
- * @param   function the function name
+ * @param   module_name_len length of the module name
+ * @param   module_data the module name
+ * @param   function_name_len length of the function name
+ * @param   function_data the function name
  * @param   arity the function arity
  */
-void atom_write_mfa(char *buf, size_t buf_size, AtomString module, AtomString function, unsigned int arity);
+void atom_write_mfa(char *buf, size_t buf_size, size_t module_name_len, const void *module_data, size_t function_name_len, const void *function_data, unsigned int arity);
 
 #ifdef __cplusplus
 }