Factor vector reserve code in runtime into its own function

Author: marijnh

src/rt/rust_builtin.cpp

@@ -225,13 +225,7 @@ str_from_vec(rust_task *task, rust_vec **vp)
 extern "C" CDECL void
 vec_reserve_shared(rust_task* task, type_desc* ty, rust_vec** vp,
                     size_t n_elts) {
-    size_t new_sz = n_elts * ty->size;
-    if (new_sz > (*vp)->alloc) {
-        size_t new_alloc = next_power_of_two(new_sz);
-        *vp = (rust_vec*)task->kernel->realloc(*vp, new_alloc +
-                                                sizeof(rust_vec));
-        (*vp)->alloc = new_alloc;
-    }
+    reserve_vec(task, vp, n_elts * ty->size);
 }
 
 /**

src/rt/rust_upcall.cpp

@@ -347,28 +347,17 @@ upcall_get_type_desc(rust_task *task,
 extern "C" CDECL void
 upcall_vec_grow(rust_task* task, rust_vec** vp, size_t new_sz) {
     LOG_UPCALL_ENTRY(task);
-    // FIXME factor this into a utility function
-    if (new_sz > (*vp)->alloc) {
-        size_t new_alloc = next_power_of_two(new_sz);
-        *vp = (rust_vec*)task->kernel->realloc(*vp, new_alloc +
-                                                sizeof(rust_vec));
-        (*vp)->alloc = new_alloc;
-    }
+    reserve_vec(task, vp, new_sz);
     (*vp)->fill = new_sz;
 }
 
 extern "C" CDECL void
 upcall_vec_push(rust_task* task, rust_vec** vp, type_desc* elt_ty,
                  void* elt) {
     LOG_UPCALL_ENTRY(task);
+    size_t new_sz = (*vp)->fill + elt_ty->size;
+    reserve_vec(task, vp, new_sz);
     rust_vec* v = *vp;
-    size_t new_sz = v->fill + elt_ty->size;
-    if (new_sz > v->alloc) {
-        size_t new_alloc = next_power_of_two(new_sz);
-        *vp = v = (rust_vec*)task->kernel->realloc(v, new_alloc +
-                                                    sizeof(rust_vec));
-        v->alloc = new_alloc;
-    }
     copy_elements(task, elt_ty, &v->data[0] + v->fill, elt, elt_ty->size);
     v->fill += elt_ty->size;
 }

src/rt/rust_util.h

@@ -209,6 +209,15 @@ inline size_t vec_size(size_t elems) {
     return sizeof(rust_vec) + sizeof(T) * elems;
 }
 
+inline void reserve_vec(rust_task* task, rust_vec** vpp, size_t size) {
+    if (size > (*vpp)->alloc) {
+        size_t new_alloc = next_power_of_two(size);
+        *vpp = (rust_vec*)task->kernel->realloc(*vpp, new_alloc +
+                                                sizeof(rust_vec));
+        (*vpp)->alloc = new_alloc;
+    }
+}
+
 //
 // Local Variables:
 // mode: C++