10.1.0: backport ipa-fnsummary PR96130 bug

Fixes build failure of mesa-9999

Reported-by: Rafael Kitover
Bug: https://bugs.gentoo.org/733246
Bug: https://gcc.gnu.org/PR96130
Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>

2 files changed, 105 insertions, 0 deletions

diff --git a/10.1.0/gentoo/38_all_ICE-ipa-fnsummary-PR96130.patch b/10.1.0/gentoo/38_all_ICE-ipa-fnsummary-PR96130.patch
new file mode 100644
index 0000000..56ea118
--- /dev/null
+++ b/10.1.0/gentoo/38_all_ICE-ipa-fnsummary-PR96130.patch
@@ -0,0 +1,104 @@
+https://gcc.gnu.org/PR96130
+https://bugs.gentoo.org/733246
+
+From 0d03c0ee5213703ec6d9ffa632fa5298d83adaaa Mon Sep 17 00:00:00 2001
+From: Jakub Jelinek <jakub@redhat.com>
+Date: Mon, 13 Jul 2020 18:25:53 +0200
+Subject: [PATCH] ipa-fnsummary: Fix ICE with switch predicates [PR96130]
+
+The following testcase ICEs since r10-3199.
+There is a switch with default label, where the controlling expression has
+range just 0..7 and there are case labels for all those 8 values, but
+nothing has yet optimized away the default.
+Since r10-3199, set_switch_stmt_execution_predicate sets the switch to
+default label's edge's predicate to a false predicate and then
+compute_bb_predicates propagates the predicates through the cfg, but false
+predicates aren't really added.  The caller of compute_bb_predicates
+in one place handles NULL bb->aux as false predicate:
+      if (fbi.info)
+	{
+	  if (bb->aux)
+	    bb_predicate = *(predicate *) bb->aux;
+	  else
+	    bb_predicate = false;
+	}
+      else
+	bb_predicate = true;
+but then in two further spots that the patch below is changing
+it assumes bb->aux must be non-NULL.  Those two spots are guarded by a
+condition that is only true if fbi.info is non-NULL, so I think the right
+fix is to treat NULL aux as false predicate in those spots too.
+
+2020-07-13  Jakub Jelinek  <jakub@redhat.com>
+
+	PR ipa/96130
+	* ipa-fnsummary.c (analyze_function_body): Treat NULL bb->aux
+	as false predicate.
+
+	* gcc.dg/torture/pr96130.c: New test.
+
+(cherry picked from commit 776e48e0931db69f158f40e5cb8e15463d879a42)
+---
+ gcc/ipa-fnsummary.c                    | 10 ++++++++--
+ gcc/testsuite/gcc.dg/torture/pr96130.c | 26 ++++++++++++++++++++++++++
+ 2 files changed, 34 insertions(+), 2 deletions(-)
+ create mode 100644 gcc/testsuite/gcc.dg/torture/pr96130.c
+
+--- a/gcc/ipa-fnsummary.c
++++ b/gcc/ipa-fnsummary.c
+@@ -2766,7 +2766,10 @@ analyze_function_body (struct cgraph_node *node, bool early)
+ 	  edge ex;
+ 	  unsigned int j;
+ 	  class tree_niter_desc niter_desc;
+-	  bb_predicate = *(predicate *) loop->header->aux;
++	  if (loop->header->aux)
++	    bb_predicate = *(predicate *) loop->header->aux;
++	  else
++	    bb_predicate = false;
+ 
+ 	  exits = get_loop_exit_edges (loop);
+ 	  FOR_EACH_VEC_ELT (exits, j, ex)
+@@ -2799,7 +2802,10 @@ analyze_function_body (struct cgraph_node *node, bool early)
+ 	  for (unsigned i = 0; i < loop->num_nodes; i++)
+ 	    {
+ 	      gimple_stmt_iterator gsi;
+-	      bb_predicate = *(predicate *) body[i]->aux;
++	      if (body[i]->aux)
++		bb_predicate = *(predicate *) body[i]->aux;
++	      else
++		bb_predicate = false;
+ 	      for (gsi = gsi_start_bb (body[i]); !gsi_end_p (gsi);
+ 		   gsi_next (&gsi))
+ 		{
+--- /dev/null
++++ b/gcc/testsuite/gcc.dg/torture/pr96130.c
+@@ -0,0 +1,26 @@
++/* PR ipa/96130 */
++/* { dg-do compile } */
++
++struct S { unsigned j : 3; };
++int k, l, m;
++
++void
++foo (struct S x)
++{
++  while (l != 5)
++    switch (x.j)
++      {
++      case 1:
++      case 3:
++      case 4:
++      case 6:
++      case 2:
++      case 5:
++	l = m;
++      case 7:
++      case 0:
++	k = 0;
++      default:
++	break;
++      }
++}
+-- 
+2.27.0
+
diff --git a/10.1.0/gentoo/README.history b/10.1.0/gentoo/README.history
index f081231..6fd902a 100644
--- a/10.1.0/gentoo/README.history
+++ b/10.1.0/gentoo/README.history
@@ -1,5 +1,6 @@
 4 		TODO
 	+ 37_all_sparc_pie_TEXTREL.patch
+	+ 38_all_ICE-ipa-fnsummary-PR96130.patch
 
 3		04 July 2020
 	+ 33_all_avx512-scalar-PR95528.patch