[PR64164] Drop copyrename, use coalescible partition as base when optimizing.

for  gcc/ChangeLog

	PR rtl-optimization/64164
	* Makefile.in (OBJS): Drop tree-ssa-copyrename.o.
	* tree-ssa-copyrename.c: Removed.
	* opts.c (default_options_table): Drop -ftree-copyrename.  Add
	-ftree-coalesce-vars.
	* passes.def: Drop all occurrences of pass_rename_ssa_copies.
	* common.opt (ftree-copyrename): Ignore.
	(ftree-coalesce-inlined-vars): Likewise.
	* doc/invoke.texi: Remove the ignored options above.
	* gimple-expr.h (gimple_can_coalesce_p): Move declaration
	* tree-ssa-coalesce.h: ... here.
	* tree-ssa-uncprop.c: Include tree-ssa-coalesce.h and other
	headers required by it.
	* gimple-expr.c (gimple_can_coalesce_p): Allow coalescing
	across variables when flag_tree_coalesce_vars.  Check register
	use and promoted modes to allow coalescing.  Moved to
	tree-ssa-coalesce.c.
	* tree-ssa-live.c (struct tree_int_map_hasher): Move along
	with its member functions to tree-ssa-coalesce.c.
	(var_map_base_init): Likewise.  Renamed to
	compute_samebase_partition_bases.
	(partition_view_normal): Drop want_bases parameter.
	(partition_view_bitmap): Likewise.
	* tree-ssa-live.h: Adjust declarations.
	* tree-ssa-coalesce.c: Include explow.h.
	(build_ssa_conflict_graph): Process PARM_ and RESULT_DECLs's
	default defs at the entry point.
	(dump_part_var_map): New.
	(compute_optimized_partition_bases): New, called by...
	(coalesce_ssa_name): ... when flag_tree_coalesce_vars, instead
	of compute_samebase_partition_bases.  Adjust.
	* alias.c (nonoverlapping_memrefs_p): Disregard gimple-regs.
	* cfgexpand.c (leader_merge): New.
	(get_rtl_for_parm_ssa_default_def): New.
	(set_rtl): Merge exprs and attrs, even for MEMs and non-SSA
	vars.  Update DECL_RTL for PARM_DECLs and RESULT_DECLs too.
	(expand_one_stack_var_at): Handle anonymous SSA_NAMEs.  Drop
	redundant MEM attr setting.
	(expand_one_stack_var_1): Handle anonymous SSA_NAMEs.  Renamed
	from...
	(expand_one_stack_var): ... this.  New wrapper to check and
	skip already expanded SSA partitions.
	(record_alignment_for_reg_var): New, factored out of...
	(expand_one_var): ... this.
	(expand_one_ssa_partition): New.
	(adjust_one_expanded_partition_var): New.
	(expand_one_register_var): Check and skip already expanded SSA
	partitions.
	(expand_used_vars): Don't create DECLs for anonymous SSA
	names.  Expand all SSA partitions, then adjust all SSA names.
	(pass::execute): Replace the loops that set
	SA.partition_to_pseudo from partition leaders and cleared
	DECL_RTL for multi-location variables, and that which used to
	rename vars and set attrs, with one that clears DECL_RTL and
	checks that PARMs and RESULTs default_defs match DECL_RTL.
	* cfgexpand.h (get_rtl_for_parm_ssa_default_def): Declare.
	* emit-rtl.c (set_reg_attrs_for_parm): Handle NULL decl.
	* explow.c (promote_ssa_mode): New.
	* explow.h (promote_ssa_mode): Declare.
	* expr.c (expand_expr_real_1): Handle anonymous SSA_NAMEs.
	* function.c: Include cfgexpand.h.
	(use_register_for_decl): Handle SSA_NAMEs, anonymous or not.
	(use_register_for_parm_decl): Wrapper for the above to
	special-case the result_ptr.
	(rtl_for_parm): Ditto for get_rtl_for_parm_ssa_default_def.
	(split_complex_args): Take assign_parm_data_all argument.
	Pass it to rtl_for_parm.  Set up rtl and context for split
	args.
	(assign_parms_augmented_arg_list): Adjust.
	(maybe_reset_rtl_for_parm): Reset DECL_RTL of parms with
	multiple locations.  Recognize split complex args.
	(assign_parm_adjust_stack_rtl): Add all and parm arguments,
	for rtl_for_parm.  For SSA-assigned parms, zero stack_parm.
	(assign_parm_setup_block): Prefer SSA-assigned location.
	(assign_parm_setup_reg): Likewise.  Use entry_parm for equiv
	if stack_parm is NULL.
	(assign_parm_setup_stack): Prefer SSA-assigned location.
	(assign_parms): Maybe reset DECL_RTL of params.  Adjust stack
	rtl before testing for pointer bounds.  Special-case result_ptr.
	(expand_function_start): Maybe reset DECL_RTL of result.
	Prefer SSA-assigned location for result and static chain.
	Factor out DECL_RESULT and SET_DECL_RTL.
	* tree-outof-ssa.c (insert_value_copy_on_edge): Handle
	anonymous SSA names.  Use promote_ssa_mode.
	(get_temp_reg): Likewise.
	(remove_ssa_form): Adjust.
	* stor-layout.c (layout_decl): Don't set mem attributes of
	non-MEMs.
	* var-tracking.c (dataflow_set_clear_at_call): Take call_insn
	and get its reg_usage for reg invalidation.
	(compute_bb_dataflow): Pass it insn.
	(emit_notes_in_bb): Likewise.

for  gcc/testsuite/ChangeLog

	* gcc.dg/guality/pr54200.c: Add -fno-tree-coalesce-vars.
	* gcc.dg/ssp-1.c: Make counter a register.
	* gcc.dg/ssp-2.c: Likewise.
	* gcc.dg/torture/parm-coalesce.c: New.

From-SVN: r226113

5 files changed, 51 insertions, 3 deletions

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 9743f94..8c6d7e1 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,11 @@
+2015-07-23  Alexandre Oliva <aoliva@redhat.com>
+
+	PR rtl-optimization/64164
+	* gcc.dg/guality/pr54200.c: Add -fno-tree-coalesce-vars.
+	* gcc.dg/ssp-1.c: Make counter a register.
+	* gcc.dg/ssp-2.c: Likewise.
+	* gcc.dg/torture/parm-coalesce.c: New.
+
 2015-07-23  Marek Polacek  <polacek@redhat.com>
 
 	PR sanitizer/66908
diff --git a/gcc/testsuite/gcc.dg/guality/pr54200.c b/gcc/testsuite/gcc.dg/guality/pr54200.c
index 9b17187..e1e7293 100644
--- a/gcc/testsuite/gcc.dg/guality/pr54200.c
+++ b/gcc/testsuite/gcc.dg/guality/pr54200.c
@@ -1,6 +1,6 @@
 /* PR tree-optimization/54200 */
 /* { dg-do run } */
-/* { dg-options "-g -fno-var-tracking-assignments" } */
+/* { dg-options "-g -fno-var-tracking-assignments -fno-tree-coalesce-vars" } */
 
 int o __attribute__((used));
 
diff --git a/gcc/testsuite/gcc.dg/ssp-1.c b/gcc/testsuite/gcc.dg/ssp-1.c
index 5467f4d..db69332 100644
--- a/gcc/testsuite/gcc.dg/ssp-1.c
+++ b/gcc/testsuite/gcc.dg/ssp-1.c
@@ -12,7 +12,7 @@ __stack_chk_fail (void)
 
 int main ()
 {
-  int i;
+  register int i;
   char foo[255];
 
   // smash stack
diff --git a/gcc/testsuite/gcc.dg/ssp-2.c b/gcc/testsuite/gcc.dg/ssp-2.c
index 9a7ac32..752fe53 100644
--- a/gcc/testsuite/gcc.dg/ssp-2.c
+++ b/gcc/testsuite/gcc.dg/ssp-2.c
@@ -14,7 +14,7 @@ __stack_chk_fail (void)
 void
 overflow()
 {
-  int i = 0;
+  register int i = 0;
   char foo[30];
 
   /* Overflow buffer.  */
diff --git a/gcc/testsuite/gcc.dg/torture/parm-coalesce.c b/gcc/testsuite/gcc.dg/torture/parm-coalesce.c
new file mode 100644
index 0000000..dbd81c1
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/parm-coalesce.c
@@ -0,0 +1,40 @@
+/* { dg-do run } */
+
+#include <stdlib.h>
+
+/* Make sure we don't coalesce both incoming parms, one whose incoming
+   value is unused, to the same location, so as to overwrite one of
+   them with the incoming value of the other.  */
+
+int __attribute__((noinline, noclone))
+foo (int i, int j)
+{
+  j = i; /* The incoming value for J is unused.  */
+  i = 2;
+  if (j)
+    j++;
+  j += i + 1;
+  return j;
+}
+
+/* Same as foo, but with swapped parameters.  */
+int __attribute__((noinline, noclone))
+bar (int j, int i)
+{
+  j = i; /* The incoming value for J is unused.  */
+  i = 2;
+  if (j)
+    j++;
+  j += i + 1;
+  return j;
+}
+
+int
+main (void)
+{
+  if (foo (0, 1) != 3)
+    abort ();
+  if (bar (1, 0) != 3)
+    abort ();
+  return 0;
+}