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-rw-r--r--Parser/node.c189
1 files changed, 0 insertions, 189 deletions
diff --git a/Parser/node.c b/Parser/node.c
deleted file mode 100644
index 8789e01..0000000
--- a/Parser/node.c
+++ /dev/null
@@ -1,189 +0,0 @@
-/* Parse tree node implementation */
-
-#include "Python.h"
-#include "node.h"
-#include "errcode.h"
-
-node *
-PyNode_New(int type)
-{
- node *n = (node *) PyObject_MALLOC(1 * sizeof(node));
- if (n == NULL)
- return NULL;
- n->n_type = type;
- n->n_str = NULL;
- n->n_lineno = 0;
- n->n_end_lineno = 0;
- n->n_col_offset = 0;
- n->n_end_col_offset = -1;
- n->n_nchildren = 0;
- n->n_child = NULL;
- return n;
-}
-
-/* See comments at XXXROUNDUP below. Returns -1 on overflow. */
-static int
-fancy_roundup(int n)
-{
- /* Round up to the closest power of 2 >= n. */
- int result = 256;
- assert(n > 128);
- while (result < n) {
- result <<= 1;
- if (result <= 0)
- return -1;
- }
- return result;
-}
-
-/* A gimmick to make massive numbers of reallocs quicker. The result is
- * a number >= the input. In PyNode_AddChild, it's used like so, when
- * we're about to add child number current_size + 1:
- *
- * if XXXROUNDUP(current_size) < XXXROUNDUP(current_size + 1):
- * allocate space for XXXROUNDUP(current_size + 1) total children
- * else:
- * we already have enough space
- *
- * Since a node starts out empty, we must have
- *
- * XXXROUNDUP(0) < XXXROUNDUP(1)
- *
- * so that we allocate space for the first child. One-child nodes are very
- * common (presumably that would change if we used a more abstract form
- * of syntax tree), so to avoid wasting memory it's desirable that
- * XXXROUNDUP(1) == 1. That in turn forces XXXROUNDUP(0) == 0.
- *
- * Else for 2 <= n <= 128, we round up to the closest multiple of 4. Why 4?
- * Rounding up to a multiple of an exact power of 2 is very efficient, and
- * most nodes with more than one child have <= 4 kids.
- *
- * Else we call fancy_roundup() to grow proportionately to n. We've got an
- * extreme case then (like test_longexp.py), and on many platforms doing
- * anything less than proportional growth leads to exorbitant runtime
- * (e.g., MacPython), or extreme fragmentation of user address space (e.g.,
- * Win98).
- *
- * In a run of compileall across the 2.3a0 Lib directory, Andrew MacIntyre
- * reported that, with this scheme, 89% of PyObject_REALLOC calls in
- * PyNode_AddChild passed 1 for the size, and 9% passed 4. So this usually
- * wastes very little memory, but is very effective at sidestepping
- * platform-realloc disasters on vulnerable platforms.
- *
- * Note that this would be straightforward if a node stored its current
- * capacity. The code is tricky to avoid that.
- */
-#define XXXROUNDUP(n) ((n) <= 1 ? (n) : \
- (n) <= 128 ? (int)_Py_SIZE_ROUND_UP((n), 4) : \
- fancy_roundup(n))
-
-
-void
-_PyNode_FinalizeEndPos(node *n)
-{
- int nch = NCH(n);
- node *last;
- if (nch == 0) {
- return;
- }
- last = CHILD(n, nch - 1);
- _PyNode_FinalizeEndPos(last);
- n->n_end_lineno = last->n_end_lineno;
- n->n_end_col_offset = last->n_end_col_offset;
-}
-
-int
-PyNode_AddChild(node *n1, int type, char *str, int lineno, int col_offset,
- int end_lineno, int end_col_offset)
-{
- const int nch = n1->n_nchildren;
- int current_capacity;
- int required_capacity;
- node *n;
-
- // finalize end position of previous node (if any)
- if (nch > 0) {
- _PyNode_FinalizeEndPos(CHILD(n1, nch - 1));
- }
-
- if (nch == INT_MAX || nch < 0)
- return E_OVERFLOW;
-
- current_capacity = XXXROUNDUP(nch);
- required_capacity = XXXROUNDUP(nch + 1);
- if (current_capacity < 0 || required_capacity < 0)
- return E_OVERFLOW;
- if (current_capacity < required_capacity) {
- if ((size_t)required_capacity > SIZE_MAX / sizeof(node)) {
- return E_NOMEM;
- }
- n = n1->n_child;
- n = (node *) PyObject_REALLOC(n,
- required_capacity * sizeof(node));
- if (n == NULL)
- return E_NOMEM;
- n1->n_child = n;
- }
-
- n = &n1->n_child[n1->n_nchildren++];
- n->n_type = type;
- n->n_str = str;
- n->n_lineno = lineno;
- n->n_col_offset = col_offset;
- n->n_end_lineno = end_lineno; // this and below will be updates after all children are added.
- n->n_end_col_offset = end_col_offset;
- n->n_nchildren = 0;
- n->n_child = NULL;
- return 0;
-}
-
-/* Forward */
-static void freechildren(node *);
-static Py_ssize_t sizeofchildren(node *n);
-
-
-void
-PyNode_Free(node *n)
-{
- if (n != NULL) {
- freechildren(n);
- PyObject_FREE(n);
- }
-}
-
-Py_ssize_t
-_PyNode_SizeOf(node *n)
-{
- Py_ssize_t res = 0;
-
- if (n != NULL)
- res = sizeof(node) + sizeofchildren(n);
- return res;
-}
-
-static void
-freechildren(node *n)
-{
- int i;
- for (i = NCH(n); --i >= 0; )
- freechildren(CHILD(n, i));
- if (n->n_child != NULL)
- PyObject_FREE(n->n_child);
- if (STR(n) != NULL)
- PyObject_FREE(STR(n));
-}
-
-static Py_ssize_t
-sizeofchildren(node *n)
-{
- Py_ssize_t res = 0;
- int i;
- for (i = NCH(n); --i >= 0; )
- res += sizeofchildren(CHILD(n, i));
- if (n->n_child != NULL)
- /* allocated size of n->n_child array */
- res += XXXROUNDUP(NCH(n)) * sizeof(node);
- if (STR(n) != NULL)
- res += strlen(STR(n)) + 1;
- return res;
-}