add xvect

src/codegen.c

@@ -15,6 +15,78 @@
 # error enable PIC_NONE_IS_FALSE
 #endif
 
+typedef struct xvect {
+  char *data;
+  size_t size, capa, width;
+} xvect;
+
+static inline void xv_init(xvect *, size_t);
+static inline void xv_destroy(xvect *);
+
+static inline void xv_reserve(xvect *, size_t);
+
+static inline void xv_get(xvect *, size_t, void *);
+static inline void xv_set(xvect *, size_t, void *);
+
+static inline void xv_push(xvect *, void *);
+static inline void xv_peek(xvect *, void *);
+static inline void xv_pop(xvect *, void *);
+
+static inline void
+xv_init(xvect *x, size_t width)
+{
+  x->data = NULL;
+  x->size = 0;
+  x->capa = 0;
+  x->width = width;
+}
+
+static inline void
+xv_destroy(xvect *x)
+{
+  free(x->data);
+}
+
+static inline void
+xv_reserve(xvect *x, size_t newcapa)
+{
+  x->data = realloc(x->data, newcapa * x->width);
+  x->capa = newcapa;
+}
+
+static inline void
+xv_get(xvect *x, size_t i, void *dst)
+{
+  memcpy(dst, x->data + i * x->width, x->width);
+}
+
+static inline void
+xv_set(xvect *x, size_t i, void *src)
+{
+  memcpy(x->data + i * x->width, src, x->width);
+}
+
+static inline void
+xv_push(xvect *x, void *src)
+{
+  if (x->capa <= x->size + 1) {
+    xv_reserve(x, x->size * 2 + 1);
+  }
+  xv_set(x, x->size++, src);
+}
+
+static inline void
+xv_peek(xvect *x, void *dst)
+{
+  xv_get(x, x->size, dst);
+}
+
+static inline void
+xv_pop(xvect *x, void *dst)
+{
+  xv_get(x, --x->size, dst);
+}
+
 typedef struct analyze_scope {
   /* rest args variable is counted by localc */
   bool varg;