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[tree-ssa][PATCH] Let remove_stmt not always remoev annotations (wasRe: [tree-ssa]: Code movement is a pain in the ass.)
On Mon, 11 Aug 2003, Daniel Berlin wrote:
>
>
> On Mon, 11 Aug 2003, Andrew MacLeod wrote:
>
> > On Sun, 2003-08-10 at 16:12, Diego Novillo wrote:
> > > On Sun, 2003-08-10 at 15:38, Daniel Berlin wrote:
> > >
> > > > > I meant implementing bsi_move in terms of bsi_remove and bsi_insert.
> > > > > Is
> > > > > that feasible?
> > > > Yes, but it will require adding an extra argument to bsi_remove and
> > > > remove_stmt.
> > > >
> > > Or commonize some of the code in bsi_remove/remove_stmt. Though, if
> > > that's too intrusive then I guess we add the argument.
> > >
> > >
> >
> > bsi_remove is pretty simple... If you really want to not duplicate that
> > piece of code, common it out into a new function, add the parameter and
> > call it from bsi_remove. I wouldn't want to see the API to bsi_remove()
> > changed.
>
> As you wish.
Actually, doing it this way is going to make bsi_remove a do nothing
function that is only a single line wrapper for the new function. This
seems odd all not to just add a parameter.
This is because all the annotation removal is done in remove_stmt.
So if you don't add a parameter to bsi_remove to tell it what to pass to
remove_stmt, you have to move all of bsi_remove into a new function with
the new argument.
Anywhere, here's the patch. Bootstrapped and regtested.
2003-08-11 Daniel Berlin <dberlin@dberlin.org>
* tree-cfg.c (remove_stmt): Add new argument saying whether to remove
annotations and invalidate defs. Update all callers.
(bsi_remove_real): Moved from bsi_remove, argument added.
(bsi_remove): Made into wrapper for bsi_remove_real.
Index: tree-cfg.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/Attic/tree-cfg.c,v
retrieving revision 1.1.4.143
diff -u -3 -p -r1.1.4.143 tree-cfg.c
--- tree-cfg.c 9 Aug 2003 18:19:23 -0000 1.1.4.143
+++ tree-cfg.c 11 Aug 2003 20:36:00 -0000
@@ -123,7 +123,7 @@ static void tree_loop_optimizer_finalize
static void remove_unreachable_blocks (void);
static void remove_unreachable_block (basic_block);
static void remove_bb (basic_block, int);
-static void remove_stmt (tree *);
+static void remove_stmt (tree *, bool);
static bool blocks_unreachable_p (varray_type);
static void remove_blocks (varray_type);
static varray_type find_subblocks (basic_block);
@@ -146,7 +146,7 @@ static tree *handle_switch_fallthru (tre
static enum eh_region_type get_eh_region_type (tree);
/* Block iterator helpers. */
-
+static void bsi_remove_real (block_stmt_iterator *, bool);
static block_stmt_iterator bsi_init (tree *, basic_block);
static inline void bsi_update_from_tsi
(block_stmt_iterator *, tree_stmt_iterator);
@@ -2029,16 +2029,15 @@ is_parent (basic_block bb, basic_block c
return false;
}
-
/* Remove statement pointed by iterator I.
Note that this function will wipe out control statements that
may span multiple basic blocks. Make sure that you really
want to remove the whole control structure before calling this
- function. */
+ function. Remove the annotations if REMOVE_ANNOTATIONS is true. */
-void
-bsi_remove (block_stmt_iterator *i)
+static void
+bsi_remove_real (block_stmt_iterator *i, bool remove_annotations)
{
tree t = *(i->tp);
@@ -2049,7 +2048,7 @@ bsi_remove (block_stmt_iterator *i)
basic_block op0_bb = bb_for_stmt (TREE_OPERAND (t, 0));
basic_block op1_bb = bb_for_stmt (TREE_OPERAND (t, 1));
- remove_stmt (&TREE_OPERAND (t, 0));
+ remove_stmt (&TREE_OPERAND (t, 0), remove_annotations);
/* If both operands are empty and they are not associated
with different basic blocks, then delete the whole
@@ -2058,15 +2057,21 @@ bsi_remove (block_stmt_iterator *i)
&& (op0_bb == NULL
|| op1_bb == NULL
|| op0_bb == op1_bb))
- remove_stmt (i->tp);
+ remove_stmt (i->tp, remove_annotations);
}
else
- remove_stmt (i->tp);
+ remove_stmt (i->tp, remove_annotations);
}
-
+
bsi_next (i);
}
+void
+bsi_remove (block_stmt_iterator *i)
+{
+ bsi_remove_real (i, true);
+}
+
/* Replace the contents of a stmt with another. The replacement cannot be
a COMPOUND_EXPR node, only a gimple stmt. */
@@ -2088,10 +2093,11 @@ bsi_replace (block_stmt_iterator bsi, tr
Update all references associated with it. Note that this function will
wipe out control statements that may span multiple basic blocks. Make
sure that you really want to remove the whole control structure before
- calling this function. */
+ calling this function.
+ Reset the annotations if REMOVE_ANNOTATIONS is true. */
static void
-remove_stmt (tree *stmt_p)
+remove_stmt (tree *stmt_p, bool remove_annotations)
{
varray_type vdefs;
size_t i;
@@ -2116,31 +2122,35 @@ remove_stmt (tree *stmt_p)
if (TREE_CODE (stmt) == LABEL_EXPR)
remove_decl (LABEL_EXPR_LABEL (stmt), DECL_INITIAL (current_function_decl));
- /* If the statement is already in SSA form, mark all the definitions made in
- the statement invalid.
-
- FIXME: We should probably traverse all the def-use edges originating at
- this statement to update each use of the definitions made here, but
- that is expensive and can easily be checked by every pass by
- checking if SSA_NAME_DEF_STMT is a nop. */
- defs = def_ops (stmt);
- for (i = 0; defs && i < VARRAY_ACTIVE_SIZE (defs); i++)
+ if (remove_annotations)
{
- tree *def_p = VARRAY_GENERIC_PTR (defs, i);
- if (TREE_CODE (*def_p) == SSA_NAME)
- SSA_NAME_DEF_STMT (*def_p) = build_empty_stmt ();
- }
-
- vdefs = vdef_ops (stmt);
- for (i = 0; vdefs && i < VARRAY_ACTIVE_SIZE (vdefs); i++)
- {
- tree vdef = VDEF_RESULT (VARRAY_TREE (vdefs, i));
- if (TREE_CODE (vdef) == SSA_NAME)
- SSA_NAME_DEF_STMT (vdef) = build_empty_stmt ();
+ /* If the statement is already in SSA form, mark all the
+ definitions made in the statement invalid.
+
+ FIXME: We should probably traverse all the def-use edges
+ originating at this statement to update each use of the
+ definitions made here, but that is expensive and can easily
+ be checked by every pass by checking if SSA_NAME_DEF_STMT is
+ a nop. */
+ defs = def_ops (stmt);
+ for (i = 0; defs && i < VARRAY_ACTIVE_SIZE (defs); i++)
+ {
+ tree *def_p = VARRAY_GENERIC_PTR (defs, i);
+ if (TREE_CODE (*def_p) == SSA_NAME)
+ SSA_NAME_DEF_STMT (*def_p) = build_empty_stmt ();
+ }
+
+ vdefs = vdef_ops (stmt);
+ for (i = 0; vdefs && i < VARRAY_ACTIVE_SIZE (vdefs); i++)
+ {
+ tree vdef = VDEF_RESULT (VARRAY_TREE (vdefs, i));
+ if (TREE_CODE (vdef) == SSA_NAME)
+ SSA_NAME_DEF_STMT (vdef) = build_empty_stmt ();
+ }
+
+ stmt->common.ann = NULL;
}
- stmt->common.ann = NULL;
-
/* The RHS of a MODIFY_EXPR has an annotation for the benefit of
SSA-PRE. Make sure to remove that annotation as well.
@@ -2586,7 +2596,7 @@ linearize_cond_expr (tree *entry_p, basi
remove_bb (else_block, 0);
/* And finally remove the useless statement. */
- remove_stmt (entry_p);
+ remove_stmt (entry_p, true);
return true;
}
}
@@ -2602,7 +2612,7 @@ linearize_cond_expr (tree *entry_p, basi
move_outgoing_edges (bb, then_block);
remove_bb (then_block, 0);
}
- remove_stmt (entry_p);
+ remove_stmt (entry_p, true);
}
else
merge_tree_blocks (bb, bb_for_stmt (then_clause));
@@ -2621,7 +2631,7 @@ linearize_cond_expr (tree *entry_p, basi
move_outgoing_edges (bb, else_block);
remove_bb (else_block, 0);
}
- remove_stmt (entry_p);
+ remove_stmt (entry_p, true);
}
else
merge_tree_blocks (bb, bb_for_stmt (else_clause));
>