/* High-level loop manipulation functions.
- Copyright (C) 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
-
+ Copyright (C) 2004, 2005, 2006, 2007, 2008, 2010
+ Free Software Foundation, Inc.
+
This file is part of GCC.
-
+
GCC is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation; either version 3, or (at your option) any
later version.
-
+
GCC is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
-
+
You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING3. If not see
<http://www.gnu.org/licenses/>. */
#include "coretypes.h"
#include "tm.h"
#include "tree.h"
-#include "rtl.h"
#include "tm_p.h"
-#include "hard-reg-set.h"
#include "basic-block.h"
#include "output.h"
#include "diagnostic.h"
It is expected that neither BASE nor STEP are shared with other expressions
(unless the sharing rules allow this). Use VAR as a base var_decl for it
(if NULL, a new temporary will be created). The increment will occur at
- INCR_POS (after it if AFTER is true, before it otherwise). INCR_POS and
+ INCR_POS (after it if AFTER is true, before it otherwise). INCR_POS and
AFTER can be computed using standard_iv_increment_position. The ssa versions
of the variable before and after increment will be stored in VAR_BEFORE and
VAR_AFTER (unless they are NULL). */
for (bsi = gsi_start_phis (e->dest); !gsi_end_p (bsi); gsi_next (&bsi))
find_uses_to_rename_use (bb, PHI_ARG_DEF_FROM_EDGE (gsi_stmt (bsi), e),
use_blocks, need_phis);
-
+
for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi))
find_uses_to_rename_stmt (gsi_stmt (bsi), use_blocks, need_phis);
}
-
+
/* Marks names that are used outside of the loop they are defined in
for rewrite. Records the set of blocks in that the ssa
names are defined to USE_BLOCKS. If CHANGED_BBS is not NULL,
Looking from the outer loop with the normal SSA form, the first use of k
is not well-behaved, while the second one is an induction variable with
base 99 and step 1.
-
+
If CHANGED_BBS is not NULL, we look for uses outside loops only in
the basic blocks in this set.
{
gimple def;
basic_block def_bb;
-
+
if (TREE_CODE (use) != SSA_NAME || !is_gimple_reg (use))
return;
check_loop_closed_ssa_use (bb, var);
}
-/* Checks that invariants of the loop closed ssa form are preserved. */
+/* Checks that invariants of the loop closed ssa form are preserved.
+ Call verify_ssa when VERIFY_SSA_P is true. */
void
-verify_loop_closed_ssa (void)
+verify_loop_closed_ssa (bool verify_ssa_p)
{
basic_block bb;
gimple_stmt_iterator bsi;
if (number_of_loops () <= 1)
return;
- verify_ssa (false);
+ if (verify_ssa_p)
+ verify_ssa (false);
FOR_EACH_BB (bb)
{
#ifdef ENABLE_CHECKING
if (loops_state_satisfies_p (LOOP_CLOSED_SSA))
- verify_loop_closed_ssa ();
+ verify_loop_closed_ssa (true);
#endif
first_new_block = last_basic_block;
If N is number of iterations of the loop and MAY_BE_ZERO is the condition
under that loop exits in the first iteration even if N != 0,
-
+
while (1)
{
x = phi (init, next);
becomes (with possibly the exit conditions formulated a bit differently,
avoiding the need to create a new iv):
-
+
if (MAY_BE_ZERO || N < FACTOR)
goto rest;
pre;
post;
N -= FACTOR;
-
+
} while (N >= FACTOR);
rest:
break;
post;
}
-
+
Before the loop is unrolled, TRANSFORM is called for it (only for the
unrolled loop, but not for its versioned copy). DATA is passed to
TRANSFORM. */
verify_flow_info ();
verify_dominators (CDI_DOMINATORS);
verify_loop_structure ();
- verify_loop_closed_ssa ();
+ verify_loop_closed_ssa (true);
#endif
}
compared with *NIT. When the IV type precision has to be larger
than *NIT type precision, *NIT is converted to the larger type, the
conversion code is inserted before the loop, and *NIT is updated to
- the new definition. The induction variable is incremented in the
- loop latch. Return the induction variable that was created. */
+ the new definition. When BUMP_IN_LATCH is true, the induction
+ variable is incremented in the loop latch, otherwise it is
+ incremented in the loop header. Return the induction variable that
+ was created. */
tree
-canonicalize_loop_ivs (struct loop *loop, tree *nit)
+canonicalize_loop_ivs (struct loop *loop, tree *nit, bool bump_in_latch)
{
unsigned precision = TYPE_PRECISION (TREE_TYPE (*nit));
unsigned original_precision = precision;
gsi_insert_seq_on_edge_immediate (loop_preheader_edge (loop), stmts);
}
- gsi = gsi_last_bb (loop->latch);
+ gsi = gsi_last_bb (bump_in_latch ? loop->latch : loop->header);
create_iv (build_int_cst_type (type, 0), build_int_cst (type, 1), NULL_TREE,
- loop, &gsi, true, &var_before, NULL);
+ loop, &gsi, bump_in_latch, &var_before, NULL);
rewrite_all_phi_nodes_with_iv (loop, var_before);
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