/* Dead code elimination pass for the GNU compiler.
- Copyright (C) 2002-2014 Free Software Foundation, Inc.
+ Copyright (C) 2002-2015 Free Software Foundation, Inc.
Contributed by Ben Elliston <bje@redhat.com>
and Andrew MacLeod <amacleod@redhat.com>
Adapted to use control dependence by Steven Bosscher, SUSE Labs.
#include "system.h"
#include "coretypes.h"
#include "tm.h"
-
+#include "alias.h"
+#include "symtab.h"
#include "tree.h"
+#include "fold-const.h"
#include "calls.h"
#include "gimple-pretty-print.h"
#include "predict.h"
-#include "vec.h"
-#include "hashtab.h"
-#include "hash-set.h"
-#include "machmode.h"
#include "hard-reg-set.h"
-#include "input.h"
#include "function.h"
#include "dominance.h"
#include "cfg.h"
#include "internal-fn.h"
#include "tree-eh.h"
#include "gimple-expr.h"
-#include "is-a.h"
#include "gimple.h"
#include "gimplify.h"
#include "gimple-iterator.h"
#include "tree-ssanames.h"
#include "tree-ssa-loop-niter.h"
#include "tree-into-ssa.h"
+#include "rtl.h"
+#include "flags.h"
+#include "insn-config.h"
+#include "expmed.h"
+#include "dojump.h"
+#include "explow.h"
+#include "emit-rtl.h"
+#include "varasm.h"
+#include "stmt.h"
#include "expr.h"
#include "tree-dfa.h"
#include "tree-pass.h"
-#include "flags.h"
#include "cfgloop.h"
#include "tree-scalar-evolution.h"
#include "tree-chkp.h"
break;
case GIMPLE_ASSIGN:
- if (TREE_CODE (gimple_assign_lhs (stmt)) == SSA_NAME
- && TREE_CLOBBER_P (gimple_assign_rhs1 (stmt)))
+ if (gimple_clobber_p (stmt))
return;
break;
if (e != e2)
{
cfg_altered = true;
- remove_edge (e2);
+ /* If we made a BB unconditionally exit a loop then this
+ transform alters the set of BBs in the loop. Schedule
+ a fixup. */
+ if (loop_exit_edge_p (bb->loop_father, e))
+ loops_state_set (LOOPS_NEED_FIXUP);
+ remove_edge (e2);
}
else
ei_next (&ei);
/* If GSI is not necessary then remove it. */
if (!gimple_plf (stmt, STMT_NECESSARY))
{
+ /* Keep clobbers that we can keep live live. */
+ if (gimple_clobber_p (stmt))
+ {
+ ssa_op_iter iter;
+ use_operand_p use_p;
+ bool dead = false;
+ FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter, SSA_OP_USE)
+ {
+ tree name = USE_FROM_PTR (use_p);
+ if (!SSA_NAME_IS_DEFAULT_DEF (name)
+ && !bitmap_bit_p (processed, SSA_NAME_VERSION (name)))
+ {
+ dead = true;
+ break;
+ }
+ }
+ if (!dead)
+ continue;
+ }
if (!is_gimple_debug (stmt))
something_changed = true;
remove_dead_stmt (&gsi, bb);