From 1bfe86763414d6e37228282ae99a1c3cc2ec4316 Mon Sep 17 00:00:00 2001
From: "Elf M. Sternberg" <elf.sternberg@gmail.com>
Date: Fri, 30 Dec 2016 10:53:24 -0800
Subject: [PATCH] Cleaning up.

---
 src/collector.c | 238 ------------------------------------------------
 1 file changed, 238 deletions(-)
 delete mode 100644 src/collector.c

diff --git a/src/collector.c b/src/collector.c
deleted file mode 100644
index 4daa110..0000000
--- a/src/collector.c
+++ /dev/null
@@ -1,238 +0,0 @@
-#include <stdio.h>
-#include <stdlib.h>
-
-#define MAX_STACK 256
-#define MAX_BARRIER 8
-
-typedef enum {
-  OBJ_INT,
-  OBJ_PAIR
-} ObjectType;
-
-typedef struct sObject {
-  unsigned char marked;
-  struct sObject* next;
-  ObjectType type;
-  union {
-    int value;
-    struct {
-      struct sObject* head;
-      struct sObject* tail;
-    };
-  };
-} Object;
-
-typedef struct {
-  Object* stack[MAX_STACK];
-  Object* root;
-  int stackSize;
-  int numObjects;
-  int maxObjects;
-} VM;
-
-void assert(int condition, const char* message) {
-  if (!condition) {
-    printf("%s\n", message);
-    exit(1);
-  }
-}
-
-VM* newVM() {
-  VM* vm = malloc(sizeof(VM));
-  vm->stackSize = 0;
-  vm->numObjects = 0;
-  vm->maxObjects = MAX_BARRIER;
-  return vm;
-}
-
-void push(VM* vm, Object* value) {
-  assert(vm->stackSize < MAX_STACK, "Stack overflow!");
-  vm->stack[vm->stackSize++] = value;
-}
-
-Object* pop(VM* vm) {
-  assert(vm->stackSize > 0, "Stack underflow!");
-  return vm->stack[--(vm->stackSize)];
-}
-
-void mark(Object* object) {
-  if (object->marked) {
-    return;
-  }
-  
-  object->marked = 1;
-  if (object->type == OBJ_PAIR) {
-    mark(object->head);
-    mark(object->tail);
-  }
-}
-
-void markAll(VM* vm) {
-  for(int i = 0; i < vm->stackSize; i++) {
-    mark(vm->stack[i]);
-  }
-}
-
-void sweep(VM* vm) {
-  Object** object = &vm->root;
-  while (*object) {
-    if (!(*object)->marked) {
-      Object* unreached = *object;
-      *object = unreached->next;
-      vm->numObjects--;
-      free(unreached);
-    } else {
-      (*object)->marked = 0;
-      object = &(*object)->next;
-    }
-  }
-}
-
-void gc(VM* vm) {
-  int numObjects = vm->numObjects;
-  markAll(vm);
-  sweep(vm);
-  vm->maxObjects = vm->numObjects * 2;
-  printf("Collected %d objects, %d remaining.\n", numObjects - vm->numObjects,
-         vm->numObjects);
-}
-
-Object *newObject(VM* vm, ObjectType type) {
-  if (vm->numObjects == vm->maxObjects) {
-    gc(vm);
-  }
-
-  Object* object = malloc(sizeof(Object));
-  object->marked = 0;
-  object->type = type;
-  object->next = vm->root;
-  vm->root = object;
-  vm->numObjects++;
-  return object;
-}
-
-Object* pushInt(VM* vm, int value) {
-  Object* object = newObject(vm, OBJ_INT);
-  object->value = value;
-  push(vm, object);
-  return object;
-}
-
-Object* pushPair(VM* vm) {
-  Object* object = newObject(vm, OBJ_PAIR);
-  object->head = pop(vm);
-  object->tail = pop(vm);
-  push(vm, object);
-  return object;
-}
-  
-void freeVM(VM *vm) {
-  vm->stackSize = 0;
-  gc(vm);
-  free(vm);
-}
-
-void objectPrint(Object* object) {
-  switch(object->type) {
-  case OBJ_INT:
-    printf("%d\n", object->value);
-    break;
-
-  case OBJ_PAIR:
-    printf("(");
-    objectPrint(object->head);
-    printf(", ");
-    objectPrint(object->tail);
-    printf(")");
-    break;
-  }
-}
-
-void test1() {
-  printf("Test 1: Objects on stack are preserved.\n");
-  VM* vm = newVM();
-  pushInt(vm, 1);
-  pushInt(vm, 2);
-
-  gc(vm);
-  assert(vm->numObjects == 2, "Should have preserved objects.");
-  freeVM(vm);
-}
-
-void test2() {
-  printf("Test 2: Unreached objects are collected.\n");
-  VM* vm = newVM();
-  pushInt(vm, 1);
-  pushInt(vm, 2);
-  pop(vm);
-  pop(vm);
-
-  gc(vm);
-  assert(vm->numObjects == 0, "Should have collected objects.");
-  freeVM(vm);
-}
-
-void test3() {
-  printf("Test 3: Reach nested objects.\n");
-  VM* vm = newVM();
-  pushInt(vm, 1);
-  pushInt(vm, 2);
-  pushPair(vm);
-  pushInt(vm, 3);
-  pushInt(vm, 4);
-  pushPair(vm);
-  pushPair(vm);
-
-  gc(vm);
-  assert(vm->numObjects == 7, "Should have reached objects.");
-  freeVM(vm);
-}
-
-void test4() {
-  printf("Test 4: Handle cycles.\n");
-  VM* vm = newVM();
-  pushInt(vm, 1);
-  pushInt(vm, 2);
-  Object* a = pushPair(vm);
-  pushInt(vm, 3);
-  pushInt(vm, 4);
-  Object* b = pushPair(vm);
-
-  /* Set up a cycle, and also make 2 and 4 unreachable and collectible. */
-  a->tail = b;
-  b->tail = a;
-
-  gc(vm);
-  assert(vm->numObjects == 4, "Should have collected objects.");
-  freeVM(vm);
-}
-
-void perfTest() {
-  printf("Performance Test.\n");
-  VM* vm = newVM();
-
-  for (int i = 0; i < 1000; i++) {
-    for (int j = 0; j < 20; j++) {
-      pushInt(vm, i);
-    }
-
-    for (int k = 0; k < 20; k++) {
-      pop(vm);
-    }
-  }
-  freeVM(vm);
-}
-
-int main(int argc, const char * argv[]) {
-  test1();
-  test2();
-  test3();
-  test4();
-  perfTest();
-
-  return 0;
-}
-
-
-
-