public inbox for gcc-patches@gcc.gnu.org
 help / color / mirror / Atom feed
* [COMMITTED] Remove pass counting in VRP.
@ 2023-10-03 14:32 Andrew MacLeod
  2023-10-03 17:02 ` David Malcolm
  0 siblings, 1 reply; 4+ messages in thread
From: Andrew MacLeod @ 2023-10-03 14:32 UTC (permalink / raw)
  To: gcc-patches; +Cc: dmalcolm

[-- Attachment #1: Type: text/plain, Size: 687 bytes --]

Pass counting in VRP is used to decide when to call early VRP, pass the 
flag to enable warnings, and when the final pass is.

If you try to add additional passes, this becomes quite fragile. This 
patch simply chooses the pass based on the data pointer passed in, and 
remove the pass counter.   The first FULL VRP pass invokes the warning 
code, and the flag passed in now represents the FINAL pass of VRP.  
There is no longer a global flag which, as it turns out, wasn't working 
well with the JIT compiler, but when undetected.  (Thanks to dmalcolm 
for helping me sort out what was going on there)


Bootstraps  on x86_64-pc-linux-gnu with no regressions.   Pushed.

Andrew

[-- Attachment #2: 0002-Remove-pass-counting-in-VRP.patch --]
[-- Type: text/x-patch, Size: 3647 bytes --]

From 29abc475a360ad14d5f692945f2805fba1fdc679 Mon Sep 17 00:00:00 2001
From: Andrew MacLeod <amacleod@redhat.com>
Date: Thu, 28 Sep 2023 09:19:32 -0400
Subject: [PATCH 2/5] Remove pass counting in VRP.

Rather than using a pass count to decide which parameters are passed to
VRP, makemit explicit.

	* passes.def (pass_vrp): Use parameter for final pass flag..
	* tree-vrp.cc (vrp_pass_num): Remove.
	(run_warning_pass): New.
	(pass_vrp::my_pass): Remove.
	(pass_vrp::final_p): New.
	(pass_vrp::set_pass_param): Set final_p param.
	(pass_vrp::execute): Choose specific pass based on data pointer.
---
 gcc/passes.def  |  4 ++--
 gcc/tree-vrp.cc | 26 +++++++++++++++++---------
 2 files changed, 19 insertions(+), 11 deletions(-)

diff --git a/gcc/passes.def b/gcc/passes.def
index 4110a472914..2bafd60bbfb 100644
--- a/gcc/passes.def
+++ b/gcc/passes.def
@@ -221,7 +221,7 @@ along with GCC; see the file COPYING3.  If not see
       NEXT_PASS (pass_fre, true /* may_iterate */);
       NEXT_PASS (pass_merge_phi);
       NEXT_PASS (pass_thread_jumps_full, /*first=*/true);
-      NEXT_PASS (pass_vrp, true /* warn_array_bounds_p */);
+      NEXT_PASS (pass_vrp, false /* final_p*/);
       NEXT_PASS (pass_dse);
       NEXT_PASS (pass_dce);
       /* pass_stdarg is always run and at this point we execute
@@ -348,7 +348,7 @@ along with GCC; see the file COPYING3.  If not see
       NEXT_PASS (pass_dominator, false /* may_peel_loop_headers_p */);
       NEXT_PASS (pass_strlen);
       NEXT_PASS (pass_thread_jumps_full, /*first=*/false);
-      NEXT_PASS (pass_vrp, false /* warn_array_bounds_p */);
+      NEXT_PASS (pass_vrp, true /* final_p */);
       /* Run CCP to compute alignment and nonzero bits.  */
       NEXT_PASS (pass_ccp, true /* nonzero_p */);
       NEXT_PASS (pass_warn_restrict);
diff --git a/gcc/tree-vrp.cc b/gcc/tree-vrp.cc
index d7b194f5904..05266dfe34a 100644
--- a/gcc/tree-vrp.cc
+++ b/gcc/tree-vrp.cc
@@ -1120,36 +1120,44 @@ const pass_data pass_data_early_vrp =
   ( TODO_cleanup_cfg | TODO_update_ssa | TODO_verify_all ),
 };
 
-static int vrp_pass_num = 0;
+static bool run_warning_pass = true;
 class pass_vrp : public gimple_opt_pass
 {
 public:
   pass_vrp (gcc::context *ctxt, const pass_data &data_)
-    : gimple_opt_pass (data_, ctxt), data (data_), warn_array_bounds_p (false),
-      my_pass (vrp_pass_num++)
-  {}
+    : gimple_opt_pass (data_, ctxt), data (data_),
+      warn_array_bounds_p (false), final_p (false)
+  {
+    // Only the frst VRP pass should run warnings.
+    if (&data == &pass_data_vrp)
+      {
+	warn_array_bounds_p = run_warning_pass;
+	run_warning_pass = false;
+      }
+  }
 
   /* opt_pass methods: */
   opt_pass * clone () final override { return new pass_vrp (m_ctxt, data); }
   void set_pass_param (unsigned int n, bool param) final override
     {
       gcc_assert (n == 0);
-      warn_array_bounds_p = param;
+      final_p = param;
     }
   bool gate (function *) final override { return flag_tree_vrp != 0; }
   unsigned int execute (function *fun) final override
     {
       // Early VRP pass.
-      if (my_pass == 0)
-	return execute_ranger_vrp (fun, /*warn_array_bounds_p=*/false, false);
+      if (&data == &pass_data_early_vrp)
+	return execute_ranger_vrp (fun, /*warn_array_bounds_p=*/false,
+				   /*final_p=*/false);
 
-      return execute_ranger_vrp (fun, warn_array_bounds_p, my_pass == 2);
+      return execute_ranger_vrp (fun, warn_array_bounds_p, final_p);
     }
 
  private:
   const pass_data &data;
   bool warn_array_bounds_p;
-  int my_pass;
+  bool final_p;
 }; // class pass_vrp
 
 const pass_data pass_data_assumptions =
-- 
2.41.0


^ permalink raw reply	[flat|nested] 4+ messages in thread
end of thread, other threads:[~2023-10-03 17:27 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2023-10-03 14:32 [COMMITTED] Remove pass counting in VRP Andrew MacLeod
2023-10-03 17:02 ` David Malcolm
2023-10-03 17:11   ` Andrew MacLeod
2023-10-03 17:27     ` David Malcolm

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).