/* Calculate (post)dominators in slightly super-linear time.
- Copyright (C) 2000, 2003, 2004, 2005, 2006, 2007, 2008 Free
- Software Foundation, Inc.
+ Copyright (C) 2000, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
+ Free Software Foundation, Inc.
Contributed by Michael Matz (matz@ifh.de).
This file is part of GCC.
#include "hard-reg-set.h"
#include "obstack.h"
#include "basic-block.h"
-#include "toplev.h"
+#include "diagnostic-core.h"
#include "et-forest.h"
#include "timevar.h"
#include "vecprim.h"
#include "pointer-set.h"
#include "graphds.h"
+#include "bitmap.h"
/* We name our nodes with integers, beginning with 1. Zero is reserved for
'undefined' or 'end of list'. The name of each node is given by the dfs
/* Set the immediate dominator of the block possibly removing
existing edge. NULL can be used to remove any edge. */
-inline void
+void
set_immediate_dominator (enum cdi_direction dir, basic_block bb,
basic_block dominated_by)
{
unsigned int dir_index = dom_convert_dir_to_idx (dir);
struct et_node *node = bb->dom[dir_index];
-
+
gcc_assert (dom_computed[dir_index]);
if (node->father)
VEC (basic_block, heap) *
get_dominated_by (enum cdi_direction dir, basic_block bb)
{
- int n;
unsigned int dir_index = dom_convert_dir_to_idx (dir);
struct et_node *node = bb->dom[dir_index], *son = node->son, *ason;
VEC (basic_block, heap) *bbs = NULL;
return NULL;
VEC_safe_push (basic_block, heap, bbs, (basic_block) son->data);
- for (ason = son->right, n = 1; ason != son; ason = ason->right)
+ for (ason = son->right; ason != son; ason = ason->right)
VEC_safe_push (basic_block, heap, bbs, (basic_block) ason->data);
return bbs;
/* Returns the list of basic blocks that are immediately dominated (in
direction DIR) by some block between N_REGION ones stored in REGION,
except for blocks in the REGION itself. */
-
+
VEC (basic_block, heap) *
get_dominated_by_region (enum cdi_direction dir, basic_block *region,
unsigned n_region)
return doms;
}
+/* Returns the list of basic blocks including BB dominated by BB, in the
+ direction DIR up to DEPTH in the dominator tree. The DEPTH of zero will
+ produce a vector containing all dominated blocks. The vector will be sorted
+ in preorder. */
+
+VEC (basic_block, heap) *
+get_dominated_to_depth (enum cdi_direction dir, basic_block bb, int depth)
+{
+ VEC(basic_block, heap) *bbs = NULL;
+ unsigned i;
+ unsigned next_level_start;
+
+ i = 0;
+ VEC_safe_push (basic_block, heap, bbs, bb);
+ next_level_start = 1; /* = VEC_length (basic_block, bbs); */
+
+ do
+ {
+ basic_block son;
+
+ bb = VEC_index (basic_block, bbs, i++);
+ for (son = first_dom_son (dir, bb);
+ son;
+ son = next_dom_son (dir, son))
+ VEC_safe_push (basic_block, heap, bbs, son);
+
+ if (i == next_level_start && --depth)
+ next_level_start = VEC_length (basic_block, bbs);
+ }
+ while (i < next_level_start);
+
+ return bbs;
+}
+
+/* Returns the list of basic blocks including BB dominated by BB, in the
+ direction DIR. The vector will be sorted in preorder. */
+
+VEC (basic_block, heap) *
+get_all_dominated_blocks (enum cdi_direction dir, basic_block bb)
+{
+ return get_dominated_to_depth (dir, bb, 0);
+}
+
/* Redirect all edges pointing to BB to TO. */
void
redirect_immediate_dominators (enum cdi_direction dir, basic_block bb,
{
unsigned int dir_index = dom_convert_dir_to_idx (dir);
struct et_node *bb_node, *to_node, *son;
-
+
bb_node = bb->dom[dir_index];
to_node = to->dom[dir_index];
unsigned i, first;
bitmap_iterator bi;
basic_block dom;
-
+
first = bitmap_first_set_bit (blocks);
dom = BASIC_BLOCK (first);
EXECUTE_IF_SET_IN_BITMAP (blocks, 0, i, bi)
You can view these as bounds for the range of dfs numbers the
nodes in the subtree of the dominator tree rooted at that node
will contain.
-
+
The dominator tree is always a simple acyclic tree, so there are
only three possible relations two nodes in the dominator tree have
to each other:
-
+
1. Node A is above Node B (and thus, Node A dominates node B)
A
B, and DFS_Number_Out of A will be >= DFS_Number_Out of B. This is
because we must hit A in the dominator tree *before* B on the walk
down, and we will hit A *after* B on the walk back up
-
+
2. Node A is below node B (and thus, node B dominates node A)
-
-
+
+
B
|
A
In the above case, DFS_Number_In of A will be >= DFS_Number_In of
B, and DFS_Number_Out of A will be <= DFS_Number_Out of B.
-
+
This is because we must hit A in the dominator tree *after* B on
the walk down, and we will hit A *before* B on the walk back up
-
+
3. Node A and B are siblings (and thus, neither dominates the other)
C
A_Dominates_B (node A, node B)
{
- return DFS_Number_In(A) <= DFS_Number_In(B)
+ return DFS_Number_In(A) <= DFS_Number_In(B)
&& DFS_Number_Out (A) >= DFS_Number_Out(B);
}
/* Return TRUE in case BB1 is dominated by BB2. */
bool
dominated_by_p (enum cdi_direction dir, const_basic_block bb1, const_basic_block bb2)
-{
+{
unsigned int dir_index = dom_convert_dir_to_idx (dir);
struct et_node *n1 = bb1->dom[dir_index], *n2 = bb2->dom[dir_index];
-
+
gcc_assert (dom_computed[dir_index]);
if (dom_computed[dir_index] == DOM_OK)
}
/* Verify invariants of dominator structure. */
-void
+DEBUG_FUNCTION void
verify_dominators (enum cdi_direction dir)
{
int err = 0;
for (i = nc - 1; i >= 0; i--)
{
dom = NULL;
- for (si = 0; VEC_iterate (int, sccs[i], si, a); si++)
+ FOR_EACH_VEC_ELT (int, sccs[i], si, a)
{
bb = VEC_index (basic_block, bbs, a);
FOR_EACH_EDGE (e, ei, bb->preds)
}
gcc_assert (dom != NULL);
- for (si = 0; VEC_iterate (int, sccs[i], si, a); si++)
+ FOR_EACH_VEC_ELT (int, sccs[i], si, a)
{
bb = VEC_index (basic_block, bbs, a);
set_immediate_dominator (CDI_DOMINATORS, bb, dom);
conservatively correct, setting the dominators using the
heuristics in prune_bbs_to_update_dominators could
create cycles in the dominance "tree", and cause ICE. */
- for (i = 0; VEC_iterate (basic_block, bbs, i, bb); i++)
+ FOR_EACH_VEC_ELT (basic_block, bbs, i, bb)
set_immediate_dominator (CDI_DOMINATORS, bb, NULL);
}
/* Construct the graph G. */
map = pointer_map_create ();
- for (i = 0; VEC_iterate (basic_block, bbs, i, bb); i++)
+ FOR_EACH_VEC_ELT (basic_block, bbs, i, bb)
{
/* If the dominance tree is conservatively correct, split it now. */
if (conservative)
g = new_graph (n + 1);
for (y = 0; y < g->n_vertices; y++)
g->vertices[y].data = BITMAP_ALLOC (NULL);
- for (i = 0; VEC_iterate (basic_block, bbs, i, bb); i++)
+ FOR_EACH_VEC_ELT (basic_block, bbs, i, bb)
{
FOR_EACH_EDGE (e, ei, bb->preds)
{
dom_i = (size_t) *pointer_map_contains (map, dom);
/* Do not include parallel edges to G. */
- if (bitmap_bit_p ((bitmap) g->vertices[dom_i].data, i))
+ if (!bitmap_set_bit ((bitmap) g->vertices[dom_i].data, i))
continue;
- bitmap_set_bit ((bitmap) g->vertices[dom_i].data, i);
add_edge (g, dom_i, i);
}
}
gcc_assert (!bb->dom[dir_index]);
n_bbs_in_dom_tree[dir_index]++;
-
+
bb->dom[dir_index] = et_new_tree (bb);
if (dom_computed[dir_index] == DOM_OK)
return dom_computed[dir_index] != DOM_NONE;
}
-void
+DEBUG_FUNCTION void
debug_dominance_info (enum cdi_direction dir)
{
basic_block bb, bb2;
/* Prints to stderr representation of the dominance tree (for direction DIR)
rooted in ROOT. */
-void
+DEBUG_FUNCTION void
debug_dominance_tree (enum cdi_direction dir, basic_block root)
{
debug_dominance_tree_1 (dir, root, 0, false);