namespace factor {
-context::context(cell datastack_size, cell retainstack_size,
- cell callstack_size)
- : callstack_top(NULL),
- callstack_bottom(NULL),
+context::context(cell ds_size, cell rs_size, cell cs_size)
+ : callstack_top(0),
+ callstack_bottom(0),
datastack(0),
retainstack(0),
callstack_save(0),
- datastack_seg(new segment(datastack_size, false)),
- retainstack_seg(new segment(retainstack_size, false)),
- callstack_seg(new segment(callstack_size, false)) {
+ datastack_seg(new segment(ds_size, false)),
+ retainstack_seg(new segment(rs_size, false)),
+ callstack_seg(new segment(cs_size, false)) {
reset();
}
void context::reset_datastack() {
datastack = datastack_seg->start - sizeof(cell);
+ fill_stack_seg(datastack, datastack_seg, 0x11111111);
}
void context::reset_retainstack() {
retainstack = retainstack_seg->start - sizeof(cell);
+ fill_stack_seg(retainstack, retainstack_seg, 0x22222222);
}
void context::reset_callstack() {
context_object_count * sizeof(cell));
}
+void context::fill_stack_seg(cell top_ptr, segment* seg, cell pattern) {
+#ifdef FACTOR_DEBUG
+ cell clear_start = top_ptr + sizeof(cell);
+ cell clear_size = seg->end - clear_start;
+ memset_cell((void*)clear_start, pattern, clear_size);
+#else
+ (void)top_ptr;
+ (void)seg;
+ (void)pattern;
+#endif
+}
+
+vm_error_type context::address_to_error(cell addr) {
+ if (datastack_seg->underflow_p(addr))
+ return ERROR_DATASTACK_UNDERFLOW;
+ if (datastack_seg->overflow_p(addr))
+ return ERROR_DATASTACK_OVERFLOW;
+ if (retainstack_seg->underflow_p(addr))
+ return ERROR_RETAINSTACK_UNDERFLOW;
+ if (retainstack_seg->overflow_p(addr))
+ return ERROR_RETAINSTACK_OVERFLOW;
+ // These are flipped because the callstack grows downwards.
+ if (callstack_seg->underflow_p(addr))
+ return ERROR_CALLSTACK_OVERFLOW;
+ if (callstack_seg->overflow_p(addr))
+ return ERROR_CALLSTACK_UNDERFLOW;
+ return ERROR_MEMORY;
+}
+
void context::reset() {
reset_datastack();
reset_retainstack();
reset_context_objects();
}
+void context::fix_stacks() {
+ if (datastack + sizeof(cell) < datastack_seg->start ||
+ datastack + stack_reserved >= datastack_seg->end)
+ reset_datastack();
+
+ if (retainstack + sizeof(cell) < retainstack_seg->start ||
+ retainstack + stack_reserved >= retainstack_seg->end)
+ reset_retainstack();
+}
+
context::~context() {
delete datastack_seg;
delete retainstack_seg;
delete callstack_seg;
}
-/* called on startup */
-/* Allocates memory (new_context()) */
-void factor_vm::init_contexts(cell datastack_size_, cell retainstack_size_,
- cell callstack_size_) {
- datastack_size = datastack_size_;
- retainstack_size = retainstack_size_;
- callstack_size = callstack_size_;
-
- ctx = NULL;
- spare_ctx = new_context();
-}
-
-void factor_vm::delete_contexts() {
- FACTOR_ASSERT(!ctx);
- std::list<context*>::const_iterator iter = unused_contexts.begin();
- std::list<context*>::const_iterator end = unused_contexts.end();
- while (iter != end) {
- delete *iter;
- iter++;
- }
-}
-
context* factor_vm::new_context() {
context* new_context;
return new_context;
}
-/* Allocates memory */
+// Allocates memory
void factor_vm::init_context(context* ctx) {
- ctx->context_objects[OBJ_CONTEXT] = allot_alien(ctx);
+ ctx->context_objects[OBJ_CONTEXT] = allot_alien((cell)ctx);
}
-/* Allocates memory (init_context(), but not parent->new_context() */
-context* new_context(factor_vm* parent) {
+// Allocates memory (init_context(), but not parent->new_context()
+VM_C_API context* new_context(factor_vm* parent) {
context* new_context = parent->new_context();
parent->init_context(new_context);
return new_context;
}
-void factor_vm::delete_context(context* old_context) {
- unused_contexts.push_back(old_context);
- active_contexts.erase(old_context);
+void factor_vm::delete_context() {
+ unused_contexts.push_back(ctx);
+ active_contexts.erase(ctx);
while (unused_contexts.size() > 10) {
context* stale_context = unused_contexts.front();
}
}
-VM_C_API void delete_context(factor_vm* parent, context* old_context) {
- parent->delete_context(old_context);
+VM_C_API void delete_context(factor_vm* parent) {
+ parent->delete_context();
}
-/* Allocates memory (init_context()) */
-VM_C_API void reset_context(factor_vm* parent, context* ctx) {
+// Allocates memory (init_context())
+VM_C_API void reset_context(factor_vm* parent) {
+
+ // The function is used by (start-context-and-delete) which expects
+ // the top two datastack items to be preserved after the context has
+ // been resetted.
+
+ context* ctx = parent->ctx;
+ cell arg1 = ctx->pop();
+ cell arg2 = ctx->pop();
ctx->reset();
+ ctx->push(arg2);
+ ctx->push(arg1);
parent->init_context(ctx);
}
-/* Allocates memory */
+// Allocates memory
cell factor_vm::begin_callback(cell quot_) {
data_root<object> quot(quot_, this);
return quot.value();
}
-/* Allocates memory */
+// Allocates memory
cell begin_callback(factor_vm* parent, cell quot) {
return parent->begin_callback(quot);
}
void factor_vm::end_callback() {
callback_ids.pop_back();
- delete_context(ctx);
+ delete_context();
}
void end_callback(factor_vm* parent) { parent->end_callback(); }
ctx->replace(other_ctx->context_objects[n]);
}
-/* Allocates memory */
-cell factor_vm::stack_to_array(cell bottom, cell top) {
+// Allocates memory
+cell factor_vm::stack_to_array(cell bottom, cell top, vm_error_type error) {
fixnum depth = (fixnum)(top - bottom + sizeof(cell));
- if (depth < 0)
- return false_object;
- else {
- array* a = allot_uninitialized_array<array>(depth / sizeof(cell));
- memcpy(a + 1, (void*)bottom, depth);
- return tag<array>(a);
+ if (depth < 0) {
+ general_error(error, false_object, false_object);
}
+ array* a = allot_uninitialized_array<array>(depth / sizeof(cell));
+ memcpy(a + 1, (void*)bottom, depth);
+ return tag<array>(a);
}
-/* Allocates memory */
+// Allocates memory
cell factor_vm::datastack_to_array(context* ctx) {
- cell array = stack_to_array(ctx->datastack_seg->start, ctx->datastack);
- if (array == false_object) {
- general_error(ERROR_DATASTACK_UNDERFLOW, false_object, false_object);
- return false_object;
- } else
- return array;
+ return stack_to_array(ctx->datastack_seg->start,
+ ctx->datastack,
+ ERROR_DATASTACK_UNDERFLOW);
}
-/* Allocates memory */
-void factor_vm::primitive_datastack() { ctx->push(datastack_to_array(ctx)); }
-
-/* Allocates memory */
+// Allocates memory
void factor_vm::primitive_datastack_for() {
- context* other_ctx = (context*)pinned_alien_offset(ctx->peek());
- ctx->replace(datastack_to_array(other_ctx));
+ data_root<alien> alien_ctx(ctx->pop(), this);
+ context* other_ctx = (context*)pinned_alien_offset(alien_ctx.value());
+ cell array = datastack_to_array(other_ctx);
+ ctx->push(array);
}
-/* Allocates memory */
+// Allocates memory
cell factor_vm::retainstack_to_array(context* ctx) {
- cell array = stack_to_array(ctx->retainstack_seg->start, ctx->retainstack);
- if (array == false_object) {
- general_error(ERROR_RETAINSTACK_UNDERFLOW, false_object, false_object);
- return false_object;
- } else
- return array;
+ return stack_to_array(ctx->retainstack_seg->start,
+ ctx->retainstack,
+ ERROR_RETAINSTACK_UNDERFLOW);
}
-/* Allocates memory */
-void factor_vm::primitive_retainstack() {
- ctx->push(retainstack_to_array(ctx));
-}
-
-/* Allocates memory */
+// Allocates memory
void factor_vm::primitive_retainstack_for() {
context* other_ctx = (context*)pinned_alien_offset(ctx->peek());
ctx->replace(retainstack_to_array(other_ctx));
}
-/* returns pointer to top of stack */
-cell factor_vm::array_to_stack(array* array, cell bottom) {
+// returns pointer to top of stack
+static cell array_to_stack(array* array, cell bottom) {
cell depth = array_capacity(array) * sizeof(cell);
memcpy((void*)bottom, array + 1, depth);
return bottom + depth - sizeof(cell);
}
-void factor_vm::set_datastack(context* ctx, array* array) {
- ctx->datastack = array_to_stack(array, ctx->datastack_seg->start);
-}
-
void factor_vm::primitive_set_datastack() {
- set_datastack(ctx, untag_check<array>(ctx->pop()));
-}
-
-void factor_vm::set_retainstack(context* ctx, array* array) {
- ctx->retainstack = array_to_stack(array, ctx->retainstack_seg->start);
+ array* arr = untag_check<array>(ctx->pop());
+ ctx->datastack = array_to_stack(arr, ctx->datastack_seg->start);
}
void factor_vm::primitive_set_retainstack() {
- set_retainstack(ctx, untag_check<array>(ctx->pop()));
+ array* arr = untag_check<array>(ctx->pop());
+ ctx->retainstack = array_to_stack(arr, ctx->retainstack_seg->start);
}
-/* Used to implement call( */
+// Used to implement call(
void factor_vm::primitive_check_datastack() {
fixnum out = to_fixnum(ctx->pop());
fixnum in = to_fixnum(ctx->pop());
return;
}
}
- ctx->push(true_object);
+ ctx->push(special_objects[OBJ_CANONICAL_TRUE]);
}
}