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Mostly fixing and standardising documentation.

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This commit is contained in:
Simon Brooke 2019-01-20 19:44:56 +00:00
parent 0f8bc990f2
commit 22fa7314d6
24 changed files with 770 additions and 503 deletions
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130
src/memory/conspage.c
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@ -45,9 +45,12 @@ struct cons_pointer freelist = NIL;
struct cons_page *conspages[NCONSPAGES];
/**
* Make a cons page whose serial number (i.e. index in the conspages directory) is pageno.
* Initialise all cells and prepend each to the freelist; if pageno is zero, do not prepend
* cells 0 and 1 to the freelist but initialise them as NIL and T respectively.
* Make a cons page. Initialise all cells and prepend each to the freelist;
* if `initialised_cons_pages` is zero, do not prepend cells 0 and 1 to the
* freelist but initialise them as NIL and T respectively.
* \todo we ought to handle cons space exhaustion more gracefully than just
* crashing; should probably return an exception instead, although obviously
* that exception would have to have been pre-built.
*/
void make_cons_page( ) {
struct cons_page *result = malloc( sizeof( struct cons_page ) );
@ -110,7 +113,7 @@ void make_cons_page( ) {
}
/**
* dump the allocated pages to this output stream.
* dump the allocated pages to this `output` stream.
*/
void dump_pages( FILE * output ) {
for ( int i = 0; i < initialised_cons_pages; i++ ) {
@ -125,8 +128,9 @@ void dump_pages( FILE * output ) {
}
/**
* Frees the cell at the specified pointer. Dangerous, primitive, low
* level.
* Frees the cell at the specified `pointer`; for all the types of cons-space
* object which point to other cons-space objects, cascade the decrement.
* Dangerous, primitive, low level.
*
* @pointer the cell to free
*/
@ -136,63 +140,62 @@ void free_cell( struct cons_pointer pointer ) {
debug_printf( DEBUG_ALLOC, L"Freeing cell " );
debug_dump_object( pointer, DEBUG_ALLOC );
switch ( cell->tag.value ) {
/* for all the types of cons-space object which point to other
* cons-space objects, cascade the decrement. */
case CONSTV:
dec_ref( cell->payload.cons.car );
dec_ref( cell->payload.cons.cdr );
break;
case EXCEPTIONTV:
dec_ref( cell->payload.exception.message );
dec_ref( cell->payload.exception.frame );
break;
case FUNCTIONTV:
dec_ref( cell->payload.function.source );
break;
case INTEGERTV:
dec_ref( cell->payload.integer.more );
break;
case LAMBDATV:
case NLAMBDATV:
dec_ref( cell->payload.lambda.args );
dec_ref( cell->payload.lambda.body );
break;
case RATIOTV:
dec_ref( cell->payload.ratio.dividend );
dec_ref( cell->payload.ratio.divisor );
break;
case SPECIALTV:
dec_ref( cell->payload.special.source );
break;
case STRINGTV:
case SYMBOLTV:
dec_ref( cell->payload.string.cdr );
break;
case VECTORPOINTTV:
/* for vector space pointers, free the actual vector-space
* object. Dangerous! */
debug_printf( DEBUG_ALLOC,
L"About to free vector-space object at 0x%lx\n",
cell->payload.vectorp.address );
struct vector_space_object *vso = cell->payload.vectorp.address;
switch ( vso->header.tag.value ) {
case STACKFRAMETV:
free_stack_frame( get_stack_frame( pointer ) );
break;
}
free( ( void * ) cell->payload.vectorp.address );
debug_printf( DEBUG_ALLOC,
L"Freed vector-space object at 0x%lx\n",
cell->payload.vectorp.address );
break;
}
if ( !check_tag( pointer, FREETAG ) ) {
if ( cell->count == 0 ) {
switch ( cell->tag.value ) {
case CONSTV:
dec_ref( cell->payload.cons.car );
dec_ref( cell->payload.cons.cdr );
break;
case EXCEPTIONTV:
dec_ref( cell->payload.exception.message );
dec_ref( cell->payload.exception.frame );
break;
case FUNCTIONTV:
dec_ref( cell->payload.function.source );
break;
case INTEGERTV:
dec_ref( cell->payload.integer.more );
break;
case LAMBDATV:
case NLAMBDATV:
dec_ref( cell->payload.lambda.args );
dec_ref( cell->payload.lambda.body );
break;
case RATIOTV:
dec_ref( cell->payload.ratio.dividend );
dec_ref( cell->payload.ratio.divisor );
break;
case SPECIALTV:
dec_ref( cell->payload.special.source );
break;
case STRINGTV:
case SYMBOLTV:
dec_ref( cell->payload.string.cdr );
break;
case VECTORPOINTTV:
/* for vector space pointers, free the actual vector-space
* object. Dangerous! */
debug_printf( DEBUG_ALLOC,
L"About to free vector-space object at 0x%lx\n",
cell->payload.vectorp.address );
struct vector_space_object *vso =
cell->payload.vectorp.address;
switch ( vso->header.tag.value ) {
case STACKFRAMETV:
free_stack_frame( get_stack_frame( pointer ) );
break;
}
free( ( void * ) cell->payload.vectorp.address );
debug_printf( DEBUG_ALLOC,
L"Freed vector-space object at 0x%lx\n",
cell->payload.vectorp.address );
break;
}
strncpy( &cell->tag.bytes[0], FREETAG, TAGLENGTH );
cell->payload.free.car = NIL;
cell->payload.free.cdr = freelist;
@ -210,11 +213,14 @@ void free_cell( struct cons_pointer pointer ) {
}
/**
* Allocates a cell with the specified tag. Dangerous, primitive, low
* Allocates a cell with the specified `tag`. Dangerous, primitive, low
* level.
*
* @param tag the tag of the cell to allocate - must be a valid cons space tag.
* @return the cons pointer which refers to the cell allocated.
* \todo handle the case where another cons_page cannot be allocated;
* return an exception. Which, as we cannot create such an exception when
* cons space is exhausted, means we must construct it at init time.
*/
struct cons_pointer allocate_cell( char *tag ) {
struct cons_pointer result = freelist;