On Wed, 27 Feb 2019, Richard Biener wrote:
>
> CFG cleanup is now set up to perform trivial unreachable code
> elimination before doing anything that would require up-to-date
> SSA form. Unfortunately a pending SSA update still will cause
> breakage to stmt folding triggered for example by basic-block
> merging.
>
> Fortunately it's now easy to properly "interleave" CFG cleanup
> and SSA update.
>
> Done as follows, bootstrap & regtest running on x86_64-unknown-linux-gnu.
Testing went OK, two testcases need adjustments though.
FAIL: gcc.dg/tree-ssa/reassoc-43.c scan-tree-dump-not reassoc2 "0 != 0"
here we now end up with if (_20 != 0) matching.
FAIL: g++.dg/tree-prof/devirt.C scan-tree-dump-times dom3 "folding virtual
function call to virtual unsigned int mozPersonalDictionary::AddRef" 1
FAIL: g++.dg/tree-prof/devirt.C scan-tree-dump-times dom3 "folding virtual
function call to virtual unsigned int mozPersonalDictionary::_ZThn16" 1
here both foldings now alrady happen one pass earlier (during tracer
triggered CFG cleanup). Previously the folding didn't happen because
the SSA names were marked for SSA update.
Committed as follows.
Richard.
2019-03-01 Richard Biener <rguent...@suse.de>
PR middle-end/89497
* tree-cfgcleanup.h (cleanup_tree_cfg): Add SSA update flags
argument, defaulted to zero.
* passes.c (execute_function_todo): Pass down SSA update flags
to cleanup_tree_cfg.
* tree-cfgcleanup.c: Include tree-into-ssa.h and tree-cfgcleanup.h.
(cleanup_tree_cfg_noloop): After cleanup_control_flow_pre update SSA
form if requested.
(cleanup_tree_cfg): Get and pass down SSA update flags.
* gcc.dg/tree-ssa/reassoc-43.c: Avoid false match in regex.
* g++.dg/tree-prof/devirt.C: Scan tracer dump for foldings
that happen now earlier.
Index: gcc/tree-cfgcleanup.h
===================================================================
--- gcc/tree-cfgcleanup.h (revision 269251)
+++ gcc/tree-cfgcleanup.h (working copy)
@@ -22,7 +22,7 @@ along with GCC; see the file COPYING3.
/* In tree-cfgcleanup.c */
extern bitmap cfgcleanup_altered_bbs;
-extern bool cleanup_tree_cfg (void);
+extern bool cleanup_tree_cfg (unsigned = 0);
extern bool fixup_noreturn_call (gimple *stmt);
extern bool delete_unreachable_blocks_update_callgraph (cgraph_node *dst_node,
bool update_clones);
Index: gcc/passes.c
===================================================================
--- gcc/passes.c (revision 269251)
+++ gcc/passes.c (working copy)
@@ -1927,7 +1927,7 @@ execute_function_todo (function *fn, voi
/* Always cleanup the CFG before trying to update SSA. */
if (flags & TODO_cleanup_cfg)
{
- cleanup_tree_cfg ();
+ cleanup_tree_cfg (flags & TODO_update_ssa_any);
/* When cleanup_tree_cfg merges consecutive blocks, it may
perform some simplistic propagation when removing single
Index: gcc/tree-cfgcleanup.c
===================================================================
--- gcc/tree-cfgcleanup.c (revision 269251)
+++ gcc/tree-cfgcleanup.c (working copy)
@@ -44,6 +44,9 @@ along with GCC; see the file COPYING3.
#include "gimple-fold.h"
#include "tree-ssa-loop-niter.h"
#include "cgraph.h"
+#include "tree-into-ssa.h"
+#include "tree-cfgcleanup.h"
+
/* The set of blocks in that at least one of the following changes happened:
-- the statement at the end of the block was changed
@@ -943,7 +946,7 @@ mfb_keep_latches (edge e)
Return true if the flowgraph was modified, false otherwise. */
static bool
-cleanup_tree_cfg_noloop (void)
+cleanup_tree_cfg_noloop (unsigned ssa_update_flags)
{
timevar_push (TV_TREE_CLEANUP_CFG);
@@ -1023,6 +1026,8 @@ cleanup_tree_cfg_noloop (void)
/* After doing the above SSA form should be valid (or an update SSA
should be required). */
+ if (ssa_update_flags)
+ update_ssa (ssa_update_flags);
/* Compute dominator info which we need for the iterative process below. */
if (!dom_info_available_p (CDI_DOMINATORS))
@@ -1125,9 +1130,9 @@ repair_loop_structures (void)
/* Cleanup cfg and repair loop structures. */
bool
-cleanup_tree_cfg (void)
+cleanup_tree_cfg (unsigned ssa_update_flags)
{
- bool changed = cleanup_tree_cfg_noloop ();
+ bool changed = cleanup_tree_cfg_noloop (ssa_update_flags);
if (current_loops != NULL
&& loops_state_satisfies_p (LOOPS_NEED_FIXUP))
Index: gcc/testsuite/g++.dg/tree-prof/devirt.C
===================================================================
--- gcc/testsuite/g++.dg/tree-prof/devirt.C (revision 269301)
+++ gcc/testsuite/g++.dg/tree-prof/devirt.C (working copy)
@@ -1,5 +1,5 @@
/* PR ipa/88561 */
-/* { dg-options "-O3 -fdump-tree-dom3-details" } */
+/* { dg-options "-O3 -fdump-tree-tracer-details -fdump-tree-dom3-details" } */
struct nsISupports
{
@@ -121,6 +121,6 @@ main ()
__builtin_abort ();
}
-/* { dg-final-use-not-autofdo { scan-tree-dump-times "folding virtual function
call to virtual unsigned int mozPersonalDictionary::_ZThn16" 1 "dom3" { target
{ lp64 || llp64 } } } } */
+/* { dg-final-use-not-autofdo { scan-tree-dump-times "folding virtual function
call to virtual unsigned int mozPersonalDictionary::_ZThn16" 1 "tracer" {
target { lp64 || llp64 } } } } */
/* { dg-final-use-not-autofdo { scan-tree-dump-times "folding virtual function
call to virtual unsigned int mozPersonalDictionary::_ZThn8" 1 "dom3" { target
ilp32 } } } */
-/* { dg-final-use-not-autofdo { scan-tree-dump-times "folding virtual function
call to virtual unsigned int mozPersonalDictionary::AddRef" 1 "dom3" } } */
+/* { dg-final-use-not-autofdo { scan-tree-dump-times "folding virtual function
call to virtual unsigned int mozPersonalDictionary::AddRef" 1 "tracer" } } */
Index: gcc/testsuite/gcc.dg/tree-ssa/reassoc-43.c
===================================================================
--- gcc/testsuite/gcc.dg/tree-ssa/reassoc-43.c (revision 269301)
+++ gcc/testsuite/gcc.dg/tree-ssa/reassoc-43.c (working copy)
@@ -50,4 +50,4 @@ c_parser_translation_unit (c_parser * pa
}
}
}
-/* { dg-final { scan-tree-dump-not "0 != 0" "reassoc2"} } */
+/* { dg-final { scan-tree-dump-not "\[ (\]0 != 0" "reassoc2"} } */
