[ipa-vrp] Use get/set_ptr_nonnull in ipa-vrp

Message ID 867817be-aaed-7e0f-9d77-ba9e0b639f48@linaro.org
State New
Headers show

Commit Message

Kugan Vivekanandarajah Oct. 12, 2016, 6:54 a.m.
Hi,

This patch uses the get/set_ptr_nonnull so that ipa-vrp also propagates 
nonnull ranges for pinter.

Bootstrapped and regression tested this with other patched without any 
new regressions on x86_64-linux-gnu.

Is this OK for trunk?

Thanks,
Kugan




gcc/ChangeLog:

2016-10-12  Kugan Vivekanandarajah  <kugan.vivekanandarajah@linaro.org>

	* ipa-prop.c (ipa_compute_jump_functions_for_edge): Set value range
	  for pointer type too.
	(ipcp_update_vr): set_ptr_nonnull for pointer.

gcc/testsuite/ChangeLog:

2016-10-12  Kugan Vivekanandarajah  <kugan.vivekanandarajah@linaro.org>

	* gcc.dg/ipa/vrp4.c: New test.

Comments

Kugan Vivekanandarajah Oct. 13, 2016, 11:22 p.m. | #1
Hi Honza,

On 12/10/16 22:16, Jan Hubicka wrote:
>> Hi,

>>

>> This patch uses the get/set_ptr_nonnull so that ipa-vrp also

>> propagates nonnull ranges for pinter.

>>

>> Bootstrapped and regression tested this with other patched without

>> any new regressions on x86_64-linux-gnu.

>>

>> Is this OK for trunk?

>>

>> Thanks,

>> Kugan

>>

>>

>>

>>

>> gcc/ChangeLog:

>>

>> 2016-10-12  Kugan Vivekanandarajah  <kugan.vivekanandarajah@linaro.org>

>>

>> 	* ipa-prop.c (ipa_compute_jump_functions_for_edge): Set value range

>> 	  for pointer type too.

>> 	(ipcp_update_vr): set_ptr_nonnull for pointer.

>>

>> gcc/testsuite/ChangeLog:

>>

>> 2016-10-12  Kugan Vivekanandarajah  <kugan.vivekanandarajah@linaro.org>

>>

>> 	* gcc.dg/ipa/vrp4.c: New test.

> OK, thank you!

> We should be able to derive a lot of (useful) non-null information from the

> fact that the pointers are dereferenced either prior the function call or in a

> statement that postdominate the function entry.

I will try with spec2k/2006. Do you have any specific benchmark in mind 
that I can try first?

   I guess we could also give (semi)
> useful -Wmissing-attribute=nonnull hints in that case.


I will send a follow up patch for this.

Thanks,
Kugan
>

> Honza

>

Patch

From f773226855968cc652fa6f2b2d9c70d2a5d7acdb Mon Sep 17 00:00:00 2001
From: Kugan Vivekanandarajah <kugan.vivekanandarajah@linaro.org>
Date: Wed, 12 Oct 2016 13:54:34 +1100
Subject: [PATCH 2/3] Set-nonnull-range-for-pointer-type

---
 gcc/ipa-prop.c                  | 57 +++++++++++++++++++++++++++++------------
 gcc/testsuite/gcc.dg/ipa/vrp4.c | 27 +++++++++++++++++++
 2 files changed, 68 insertions(+), 16 deletions(-)
 create mode 100644 gcc/testsuite/gcc.dg/ipa/vrp4.c

diff --git a/gcc/ipa-prop.c b/gcc/ipa-prop.c
index a1d7619..353b638 100644
--- a/gcc/ipa-prop.c
+++ b/gcc/ipa-prop.c
@@ -1668,7 +1668,22 @@  ipa_compute_jump_functions_for_edge (struct ipa_func_body_info *fbi,
 	    useful_context = true;
 	}
 
-      if (!POINTER_TYPE_P (TREE_TYPE (arg)))
+      if (POINTER_TYPE_P (TREE_TYPE (arg)))
+	{
+	  if (TREE_CODE (arg) == SSA_NAME
+	      && param_type
+	      && get_ptr_nonnull (arg))
+	    {
+	      jfunc->vr_known = true;
+	      jfunc->m_vr.type = VR_ANTI_RANGE;
+	      jfunc->m_vr.min = build_int_cst (TREE_TYPE (arg), 0);
+	      jfunc->m_vr.max = build_int_cst (TREE_TYPE (arg), 0);
+	      jfunc->m_vr.equiv = NULL;
+	    }
+	  else
+	    gcc_assert (!jfunc->vr_known);
+	}
+      else
 	{
 	  wide_int min, max;
 	  value_range_type type;
@@ -5602,27 +5617,37 @@  ipcp_update_vr (struct cgraph_node *node)
 	continue;
 
       if (vr[i].known
-	  && INTEGRAL_TYPE_P (TREE_TYPE (ddef))
-	  && !POINTER_TYPE_P (TREE_TYPE (ddef))
 	  && (vr[i].type == VR_RANGE || vr[i].type == VR_ANTI_RANGE))
 	{
 	  tree type = TREE_TYPE (ddef);
 	  unsigned prec = TYPE_PRECISION (type);
-	  if (dump_file)
+	  if (INTEGRAL_TYPE_P (TREE_TYPE (ddef)))
+	    {
+	      if (dump_file)
+		{
+		  fprintf (dump_file, "Setting value range of param %u ", i);
+		  fprintf (dump_file, "%s[",
+			   (vr[i].type == VR_ANTI_RANGE) ? "~" : "");
+		  print_decs (vr[i].min, dump_file);
+		  fprintf (dump_file, ", ");
+		  print_decs (vr[i].max, dump_file);
+		  fprintf (dump_file, "]\n");
+		}
+	      set_range_info (ddef, vr[i].type,
+			      wide_int_storage::from (vr[i].min, prec,
+						      TYPE_SIGN (type)),
+			      wide_int_storage::from (vr[i].max, prec,
+						      TYPE_SIGN (type)));
+	    }
+	  else if (POINTER_TYPE_P (TREE_TYPE (ddef))
+		   && vr[i].type == VR_ANTI_RANGE
+		   && wi::eq_p (vr[i].min, 0)
+		   && wi::eq_p (vr[i].max, 0))
 	    {
-	      fprintf (dump_file, "Setting value range of param %u ", i);
-	      fprintf (dump_file, "%s[",
-		       (vr[i].type == VR_ANTI_RANGE) ? "~" : "");
-	      print_decs (vr[i].min, dump_file);
-	      fprintf (dump_file, ", ");
-	      print_decs (vr[i].max, dump_file);
-	      fprintf (dump_file, "]\n");
+	      if (dump_file)
+		fprintf (dump_file, "Setting nonnull for %u\n", i);
+	      set_ptr_nonnull (ddef);
 	    }
-	  set_range_info (ddef, vr[i].type,
-			  wide_int_storage::from (vr[i].min, prec,
-						  TYPE_SIGN (type)),
-			  wide_int_storage::from (vr[i].max, prec,
-						  TYPE_SIGN (type)));
 	}
     }
 }
diff --git a/gcc/testsuite/gcc.dg/ipa/vrp4.c b/gcc/testsuite/gcc.dg/ipa/vrp4.c
new file mode 100644
index 0000000..d7e1f26
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/ipa/vrp4.c
@@ -0,0 +1,27 @@ 
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-ipa-cp-details" } */
+
+static __attribute__((noinline, noclone))
+int foo (int *p)
+{
+  if (!p)
+    return 0;
+  *p = 1;
+}
+
+struct st
+{
+  int a;
+  int b;
+};
+
+int bar (struct st *s)
+{
+
+  if (!s)
+    return 0;
+  foo (&s->a);
+  foo (&s->b);
+}
+
+/* { dg-final { scan-ipa-dump "Setting nonnull for 0" "cp" } } */
-- 
2.7.4