#include <assert.h>
#include <inttypes.h>
+#include <setjmp.h>
#include <stdbool.h>
#include <stdlib.h>
#include <string.h>
+/* Some terminology used in function names:
+ * - initialize: These functions take a pointer and potentially some other arguments, and use those
+ * to initialize the value pointed to by self. Initialize functions DO NOT allocate the function,
+ * so they can be used to initialize stack-allocated variables.
+ * - construct: This allocates a value for a pointer, initializes it, and returns it. This is for
+ * heap-allocated values. It may be as simple as allocating the memory, calling an initialize, and
+ * returning it.
+ * - deinitialize: These functions dereference or free any objects pointed to by the self pointer's
+ * value, but they don't actually free the self pointer. This is useful for stack-allocated objects
+ * which point to heap-allocated objects.
+ * - destruct: This dereferences or frees memory pointed to by the self argument, and all the
+ * pointers on the self argument.
+ */
+
{% for standard_library in standard_libraries %}
#include <{{standard_library}}>
{% endfor %}
typedef union Instance Instance;
struct Object;
typedef struct Object Object;
+struct EnvironmentNode;
+typedef struct EnvironmentNode EnvironmentNode;
+struct Environment;
+typedef struct Environment Environment;
+struct EnvironmentPool;
+typedef struct EnvironmentPool EnvironmentPool;
+struct Stack;
+typedef struct Stack Stack;
const char* const STRING_LITERAL_LIST[] = {
{% for string_literal in string_literal_list %}
BOOLEAN,
CLOSURE,
INTEGER,
- STRING
+ LIST,
+ STRING_CONCATENATION,
+ STRING_LITERAL,
+ STRUCTURE,
+ VOID
+};
+
+struct Closure;
+typedef struct Closure Closure;
+struct Closure
+{
+ Environment* closed;
+ Object (*call)(EnvironmentPool*, Environment*, size_t, Stack*, jmp_buf);
+};
+
+struct List;
+typedef struct List List;
+struct List
+{
+ size_t allocated;
+ size_t length;
+ Object* items;
+};
+
+struct StringConcatenation;
+typedef struct StringConcatenation StringConcatenation;
+
+struct Structure;
+typedef struct Structure Structure;
+struct Structure
+{
+ size_t reference_count;
+ size_t length;
+ const char** symbol_list;
+ Object* value_list;
};
union Instance
{
bool boolean;
- Object (*closure)(size_t, Object*);
+ Closure closure;
int32_t integer;
- const char* string;
+ List list;
+ StringConcatenation* string_concatenation;
+ const char* string_literal;
+ Structure* structure;
};
struct Object
Instance instance;
};
-const Object TRUE = {
- BOOLEAN,
- true
+const Object builtin$true = { BOOLEAN, (Instance)(bool){ true } };
+const Object builtin$false = { BOOLEAN, (Instance)(bool){ false } };
+const Object builtin$nil = { VOID, { 0 } };
+
+struct StringConcatenation
+{
+ size_t referenceCount;
+ Object left;
+ Object right;
};
-const Object FALSE = {
- BOOLEAN,
- false
+Object List_construct(size_t allocate)
+{
+ Object* items = malloc(sizeof(Object) * allocate);
+ Object result = { LIST, (Instance)(List){ allocate, 0, items } };
+ return result;
+}
+
+void List_append(Object* list, Object item)
+{
+ assert(list->type == LIST);
+
+ if(list->instance.list.allocated == list->instance.list.length)
+ {
+ list->instance.list.allocated *= 2;
+ list->instance.list.items = realloc(
+ list->instance.list.items,
+ sizeof(Object) * list->instance.list.allocated
+ );
+ }
+
+ list->instance.list.items[list->instance.list.length] = item;
+ list->instance.list.length++;
+}
+
+Object List_get(Object* list, Object index)
+{
+ assert(list->type == LIST);
+ assert(index.type == INTEGER);
+
+ return list->instance.list.items[index.instance.integer];
+}
+
+struct Stack
+{
+ uint16_t length;
+ Object items[256];
};
-struct EnvironmentNode;
-typedef struct EnvironmentNode EnvironmentNode;
+void Stack_initialize(Stack* self)
+{
+ self->length = 0;
+}
+
+Stack* Stack_construct()
+{
+ Stack* result = malloc(sizeof(Stack));
+ Stack_initialize(result);
+ return result;
+}
+
+void Stack_destruct(Stack* self)
+{
+ free(self);
+}
+
+bool Stack_any(Stack* self)
+{
+ return self->length > 0;
+}
+
+void Stack_push(Stack* self, Object item)
+{
+ assert(self->length < 256);
+ self->items[self->length] = item;
+ self->length++;
+}
+
+Object Stack_pop(Stack* self)
+{
+ assert(self->length > 0);
+ self->length--;
+ return self->items[self->length];
+}
+
+Object Object_rereference(Object self)
+{
+ switch(self.type)
+ {
+ case BOOLEAN:
+ case CLOSURE:
+ case INTEGER:
+ case STRING_LITERAL:
+ case VOID:
+ return self;
+
+ case STRING_CONCATENATION:
+ self.instance.string_concatenation->referenceCount++;
+ return self;
+
+ case STRUCTURE:
+ self.instance.structure->reference_count++;
+ return self;
+
+ default:
+ assert(false);
+ }
+}
+
+Object Structure_construct(size_t length, const char** symbol_list, Object* value_list)
+{
+ Structure* structure = malloc(sizeof(Structure));
+ structure->reference_count = 1;
+ structure->length = length;
+ structure->symbol_list = malloc(sizeof(const char*) * length);
+ structure->value_list = malloc(sizeof(Object) * length);
+
+ // TODO Don't allow assignment of mutable structures, as this screws up reference counting
+ for(size_t i = 0; i < length; i++)
+ {
+ structure->symbol_list[i] = symbol_list[i];
+ structure->value_list[i] = Object_rereference(value_list[i]);
+ }
+
+ Object result = { STRUCTURE, (Instance)structure };
+
+ return result;
+}
+
+Object Structure_get(Object* self, const char* symbol)
+{
+ assert(self->type == STRUCTURE);
+
+ for(size_t i = 0; i < self->instance.structure->length; i++)
+ {
+ if(self->instance.structure->symbol_list[i] == symbol)
+ {
+ return self->instance.structure->value_list[i];
+ }
+ }
+
+ assert(false);
+}
+
struct EnvironmentNode
{
const char* key;
EnvironmentNode* next;
};
-struct Environment;
-typedef struct Environment Environment;
struct Environment
{
+ bool mark;
+ bool live;
+
+ Environment* parent;
EnvironmentNode* root;
};
-Environment* Environment_construct()
+void Environment_initialize(Environment* self, Environment* parent)
{
- // TODO Handle malloc returning NULL
- Environment* result = malloc(sizeof(Environment));
- result->root = NULL;
- return result;
+ self->parent = parent;
+ self->root = NULL;
+
+ // We are currently only ever initializing environments at the beginning of running functions, so
+ // for now at least we can assume that we want it to be live immediately.
+ self->live = true;
}
-void Environment_destruct(Environment* self)
+void Object_deinitialize(Object* self)
+{
+ switch(self->type)
+ {
+ case BOOLEAN:
+ break;
+ case CLOSURE:
+ break;
+ case INTEGER:
+ break;
+ case STRING_LITERAL:
+ break;
+ case VOID:
+ break;
+
+ case LIST:
+ for(size_t i = 0; i < self->instance.list.length; i++) {
+ Object_deinitialize(&(self->instance.list.items[i]));
+ }
+
+ free(self->instance.list.items);
+ break;
+
+ case STRING_CONCATENATION:
+ self->instance.string_concatenation->referenceCount--;
+
+ if(self->instance.string_concatenation->referenceCount == 0)
+ {
+ Object_deinitialize(&(self->instance.string_concatenation->left));
+ Object_deinitialize(&(self->instance.string_concatenation->right));
+ free(self->instance.string_concatenation);
+ }
+ break;
+
+ case STRUCTURE:
+ self->instance.structure->reference_count--;
+
+ if(self->instance.structure->reference_count == 0)
+ {
+ for(size_t i = 0; i < self->instance.structure->length; i++)
+ {
+ Object_deinitialize(&(self->instance.structure->value_list[i]));
+ }
+ free(self->instance.structure->symbol_list);
+ free(self->instance.structure->value_list);
+ free(self->instance.structure);
+ }
+ break;
+
+ default:
+ assert(false);
+ }
+}
+
+typedef uint32_t StackSnapshot;
+
+StackSnapshot Stack_takeSnapshot(Stack* self)
+{
+ return (StackSnapshot) self->length;
+}
+
+void Stack_rewind(Stack* self, StackSnapshot snapshot)
+{
+ while(self->length > snapshot)
+ {
+ Object item = Stack_pop(self);
+ Object_deinitialize(&item);
+ }
+}
+
+void Environment_deinitialize(Environment* self)
{
EnvironmentNode* next;
for(EnvironmentNode* node = self->root; node != NULL; node = next)
{
- // No objects are allocated on the heap (yet!) so we don't need to free anything else
next = node->next;
+ Object_deinitialize(&(node->value));
free(node);
}
}
+void Environment_setLive(Environment* self, bool live)
+{
+ self->live = live;
+}
+
+void Environment_mark(Environment* self)
+{
+ if(self == NULL) return;
+ if(self->mark) return; // Prevents infinite recursion in the case of cycles
+
+ self->mark = true;
+
+ Environment_mark(self->parent);
+
+ for(EnvironmentNode* node = self->root; node != NULL; node = node->next)
+ {
+ switch(node->value.type)
+ {
+ case BOOLEAN:
+ case INTEGER:
+ case STRING_LITERAL:
+ case VOID:
+ break;
+
+ case CLOSURE:
+ Environment_mark(node->value.instance.closure.closed);
+ break;
+
+ default:
+ assert(false);
+ }
+ }
+}
+
// This need not be thread safe because environments exist on one thread only
void Environment_set(Environment* self, const char* const key, Object value)
{
}
}
+ if(self->parent != NULL)
+ {
+ return Environment_get(self->parent, symbol);
+ }
+
// TODO Handle symbol errors
assert(false);
}
-Object integerLiteral(int32_t literal)
+# define POOL_SIZE 64
+struct EnvironmentPool
{
- Object result;
- result.type = INTEGER;
- result.instance.integer = literal;
- return result;
-}
+ int8_t freeIndex;
+ bool allocatedFlags[POOL_SIZE];
+ Environment environments[POOL_SIZE];
+ EnvironmentPool* overflow;
+};
-Object stringLiteral(const char* literal)
+EnvironmentPool* EnvironmentPool_construct();
+void EnvironmentPool_initialize(EnvironmentPool*);
+void EnvironmentPool_deinitialize(EnvironmentPool*);
+void EnvironmentPool_destruct(EnvironmentPool*);
+
+EnvironmentPool* EnvironmentPool_construct()
{
- Object result;
- result.type = STRING;
- result.instance.string = literal;
+ EnvironmentPool* result = malloc(sizeof(EnvironmentPool));
+ EnvironmentPool_initialize(result);
return result;
}
-// TODO Make this conditionally added
-Object operator$negate(Object input)
+void EnvironmentPool_initialize(EnvironmentPool* self)
{
- assert(input.type == INTEGER);
+ self->overflow = NULL;
+ self->freeIndex = 0;
- Object result;
- result.type = INTEGER;
- result.instance.integer = -input.instance.integer;
- return result;
+ for(size_t i = 0; i < POOL_SIZE; i++)
+ {
+ self->allocatedFlags[i] = false;
+ self->environments[i].live = false;
+ }
}
-Object operator$add(Object left, Object right)
+void EnvironmentPool_deinitialize(EnvironmentPool* self)
{
- assert(left.type == INTEGER);
- assert(right.type == INTEGER);
+ // We can assume if this is being called, none of the Environments are live
+ for(int8_t i = 0; i < POOL_SIZE; i++)
+ {
+ if(self->allocatedFlags[i]) Environment_deinitialize(&(self->environments[i]));
+ }
- Object result;
- result.type = INTEGER;
- result.instance.integer = left.instance.integer + right.instance.integer;
- return result;
+ EnvironmentPool_destruct(self->overflow);
}
-Object operator$subtract(Object left, Object right)
+void EnvironmentPool_destruct(EnvironmentPool* self)
{
- assert(left.type == INTEGER);
- assert(right.type == INTEGER);
-
- Object result;
- result.type = INTEGER;
- result.instance.integer = left.instance.integer - right.instance.integer;
- return result;
+ if(self == NULL) return;
+ EnvironmentPool_deinitialize(self);
+ free(self);
}
-Object operator$multiply(Object left, Object right)
+void EnvironmentPool_GC(EnvironmentPool* self)
{
- assert(left.type == INTEGER);
- assert(right.type == INTEGER);
+ // Unmark all the environments
+ for(EnvironmentPool* current = self; current != NULL; current = current->overflow)
+ {
+ for(int8_t i = 0; i < POOL_SIZE; i++)
+ {
+ current->environments[i].mark = false;
+ }
+ }
- Object result;
- result.type = INTEGER;
- result.instance.integer = left.instance.integer * right.instance.integer;
- return result;
+ // Mark live enviroments and environments referenced by live environments
+ for(EnvironmentPool* current = self; current != NULL; current = current->overflow)
+ {
+ for(int8_t i = 0; i < POOL_SIZE; i++)
+ {
+ if(current->environments[i].live)
+ {
+ Environment_mark(&(current->environments[i]));
+ }
+ }
+ }
+
+ // TODO We never free pools until the very end--we could free a pool if two pools are empty
+ for(EnvironmentPool* current = self; current != NULL; current = current->overflow)
+ {
+ for(int8_t i = POOL_SIZE - 1; i >= 0; i--)
+ {
+ if(!current->environments[i].mark && current->allocatedFlags[i])
+ {
+ Environment_deinitialize(&(current->environments[i]));
+ current->allocatedFlags[i] = false;
+ current->freeIndex = i;
+ }
+ }
+ }
}
-Object operator$integerDivide(Object left, Object right)
+Environment* EnvironmentPool_allocate(EnvironmentPool* self)
{
- assert(left.type == INTEGER);
- assert(right.type == INTEGER);
+ for(EnvironmentPool* current = self; current != NULL; current = current->overflow)
+ {
+ for(; current->freeIndex < POOL_SIZE; current->freeIndex++)
+ {
+ if(!current->allocatedFlags[current->freeIndex])
+ {
+ current->allocatedFlags[current->freeIndex] = true;
+ return &(current->environments[current->freeIndex]);
+ }
+ }
+ }
- Object result;
- result.type = INTEGER;
- result.instance.integer = left.instance.integer / right.instance.integer;
- return result;
+ EnvironmentPool_GC(self);
+
+ EnvironmentPool* previous;
+ for(EnvironmentPool* current = self; current != NULL; current = current->overflow)
+ {
+ for(; current->freeIndex < POOL_SIZE; current->freeIndex++)
+ {
+ if(!current->allocatedFlags[current->freeIndex])
+ {
+ current->allocatedFlags[current->freeIndex] = true;
+ return &(current->environments[current->freeIndex]);
+ }
+ else
+ {
+ previous = current;
+ }
+ }
+ }
+
+ previous->overflow = EnvironmentPool_construct();
+ return EnvironmentPool_allocate(previous->overflow);
}
-Object operator$modularDivide(Object left, Object right)
+Environment* Environment_construct(EnvironmentPool* environmentPool, Environment* parent)
{
- assert(left.type == INTEGER);
- assert(right.type == INTEGER);
+ Environment* environment = EnvironmentPool_allocate(environmentPool);
+ Environment_initialize(environment, parent);
+ return environment;
+}
+Object integerLiteral(int32_t literal)
+{
Object result;
result.type = INTEGER;
- result.instance.integer = left.instance.integer % right.instance.integer;
+ result.instance.integer = literal;
return result;
}
-Object operator$equals(Object left, Object right)
+Object stringLiteral(const char* literal)
{
- assert(left.type == INTEGER);
- assert(right.type == INTEGER);
-
- Object result = { BOOLEAN, left.instance.integer == right.instance.integer };
+ Object result;
+ result.type = STRING_LITERAL;
+ result.instance.string_literal = literal;
return result;
}
-Object operator$notEquals(Object left, Object right)
+// TODO Make this conditionally added
+Object operator$negate(Object input)
{
- assert(left.type == INTEGER);
- assert(right.type == INTEGER);
+ assert(input.type == INTEGER);
- Object result = { BOOLEAN, left.instance.integer != right.instance.integer };
+ Object result;
+ result.type = INTEGER;
+ result.instance.integer = -input.instance.integer;
return result;
}
-Object operator$greaterThan(Object left, Object right)
+// TODO Make this conditionally added
+Object operator$concatenate(Stack* stack, jmp_buf parentJump, size_t line)
{
- assert(left.type == INTEGER);
- assert(right.type == INTEGER);
-
- Object result = { BOOLEAN, left.instance.integer > right.instance.integer };
- return result;
-}
+ Object right = Stack_pop(stack);
+ Object left = Stack_pop(stack);
-Object operator$lessThan(Object left, Object right)
-{
- assert(left.type == INTEGER);
- assert(right.type == INTEGER);
+ switch(left.type) {
+ case STRING_CONCATENATION:
+ case STRING_LITERAL:
+ break;
- Object result = { BOOLEAN, left.instance.integer < right.instance.integer };
- return result;
-}
+ default:
+ assert(false);
+ }
-Object operator$greaterThanOrEqual(Object left, Object right)
-{
- assert(left.type == INTEGER);
- assert(right.type == INTEGER);
+ switch(right.type) {
+ case STRING_CONCATENATION:
+ case STRING_LITERAL:
+ break;
- Object result = { BOOLEAN, left.instance.integer >= right.instance.integer };
- return result;
-}
+ default:
+ assert(false);
+ }
-Object operator$lessThanOrEqual(Object left, Object right)
-{
- assert(left.type == INTEGER);
- assert(right.type == INTEGER);
+ StringConcatenation* concatenation = malloc(sizeof(StringConcatenation));
+ concatenation->referenceCount = 1;
+ concatenation->left = Object_rereference(left);
+ concatenation->right = Object_rereference(right);
- Object result = { BOOLEAN, left.instance.integer <= right.instance.integer };
+ Object result = { STRING_CONCATENATION, (Instance)concatenation };
return result;
}
-Object operator$and(Object left, Object right)
+{% for id in infix_declarations %}
+Object operator${{ id.name }}(Stack* stack, jmp_buf parentJump, size_t line)
{
- assert(left.type == BOOLEAN);
- assert(right.type == BOOLEAN);
+ Object right = Stack_pop(stack);
+ Object left = Stack_pop(stack);
- Object result = { BOOLEAN, left.instance.boolean && right.instance.boolean };
- return result;
-}
+ assert(left.type == {{ id.in_type.upper() }});
+ assert(right.type == {{ id.in_type.upper() }});
-Object operator$or(Object left, Object right)
-{
- assert(left.type == BOOLEAN);
- assert(right.type == BOOLEAN);
+ {% if id.name == 'integerDivide' or id.name == 'modularDivide' %}
+ if(right.instance.integer == 0)
+ {
+ fprintf(stderr, "DivisionByZeroError on line %zu\n", line);
+ longjmp(parentJump, 1);
+ }
+ {% endif %}
- Object result = { BOOLEAN, left.instance.boolean || right.instance.boolean };
+ Object result;
+ result.type = {{ id.out_type.upper() }};
+ result.instance.{{ id.out_type.lower() }} = left.instance.{{ id.in_type.lower() }} {{ id.operator }} right.instance.{{ id.in_type.lower() }};
return result;
}
+{% endfor %}
{% if 'pow' in builtins %}
-Object builtin$pow$implementation(size_t argc, Object* args)
+Object builtin$pow$implementation(EnvironmentPool* environmentPool, Environment* parent, size_t argc, Stack* stack, jmp_buf parentJump)
{
- assert(argc == 2);
-
- Object base = args[0];
- Object exponent = args[1];
+ // Must unload items in reverse order
+ Object exponent = Stack_pop(stack);
+ Object base = Stack_pop(stack);
assert(base.type == INTEGER);
assert(exponent.type == INTEGER);
return result;
}
-Object builtin$pow = { CLOSURE, (Instance)builtin$pow$implementation };
+Object builtin$pow = { CLOSURE, (Instance)(Closure){ NULL, builtin$pow$implementation } };
{% endif %}
{% if 'print' in builtins %}
-Object builtin$print$implementation(size_t argc, Object* args)
+Object builtin$print$implementation(EnvironmentPool* environmentPool, Environment* parent, size_t argc, Stack* stack, jmp_buf parentJump)
{
+ Stack reverse_stack;
+ Stack_initialize(&reverse_stack);
+
for(size_t i = 0; i < argc; i++)
{
- Object output = args[i];
+ Stack_push(&reverse_stack, Stack_pop(stack));
+ }
+
+ while(reverse_stack.length > 0)
+ {
+ Object output = Stack_pop(&reverse_stack);
switch(output.type)
{
case BOOLEAN:
fputs(output.instance.boolean ? "true" : "false", stdout);
break;
+ case CLOSURE:
+ // TODO Print something better
+ printf("<Closure>");
+ break;
+
case INTEGER:
printf("%" PRId32, output.instance.integer);
break;
- case STRING:
+ case STRING_CONCATENATION:
+ Stack_push(stack, output.instance.string_concatenation->left);
+ builtin$print$implementation(NULL, NULL, 1, stack, parentJump);
+ Stack_push(stack, output.instance.string_concatenation->right);
+ builtin$print$implementation(NULL, NULL, 1, stack, parentJump);
+ break;
+
+ case STRING_LITERAL:
// Using fwrite instead of printf to handle size_t length
- printf("%s", output.instance.string);
+ printf("%s", output.instance.string_literal);
+ break;
+
+ case VOID:
+ printf("nil");
break;
default:
assert(false);
}
+ Object_deinitialize(&output);
}
// TODO Return something better
- return FALSE;
+ return builtin$false;
}
-Object builtin$print = { CLOSURE, (Instance)builtin$print$implementation };
+Object builtin$print = { CLOSURE, (Instance)(Closure){ NULL, builtin$print$implementation } };
{% endif %}
+{% for function_definition in function_definition_list %}
+{{ function_definition }}
+{% endfor %}
int main(int argc, char** argv)
{
- Environment* environment = Environment_construct();
+ EnvironmentPool* environmentPool = EnvironmentPool_construct();
+ Environment* environment = EnvironmentPool_allocate(environmentPool);
+ Environment_initialize(environment, NULL);
+
+ Stack stackMemory;
+ Stack* stack = &stackMemory;
+ Stack_initialize(stack);
+
+ jmp_buf jump;
+ if(setjmp(jump) != 0)
+ {
+ fprintf(stderr, "\tin __main__\n");
+
+ while(Stack_any(stack))
+ {
+ Object item = Stack_pop(stack);
+ Object_deinitialize(&item);
+ }
+ Environment_setLive(environment, false);
+ EnvironmentPool_destruct(environmentPool);
+
+ // TODO We would like to return something nonzero here, but that messes up Valgrind so we couldn't catch memory leaks
+ return 0;
+ }
+
+ // TODO Use the symbol from SYMBOL_LIST
+ {% for builtin in builtins %}
+ Environment_set(environment, "{{ builtin }}", builtin${{ builtin }});
+ {% endfor %}
{% for statement in statements %}
{{ statement }}
{% endfor %}
- Environment_destruct(environment);
-
+ Environment_setLive(environment, false);
+ EnvironmentPool_destruct(environmentPool);
return 0;
}