backport: re PR target/81766 (ICE in maybe_add_or_update_dep_1, at sched-deps.c:924...

	Backported from mainline
	2017-08-08  Richard Biener  <rguenther@suse.de>

	PR middle-end/81766
	* function.c (thread_prologue_and_epilogue_insns): Restore
	behavior of always calling find_many_sub_basic_blocks on
	the inserted prologue.

	* gcc.target/i386/pr81766.c: New testcase.

	2017-08-02  Jakub Jelinek  <jakub@redhat.com>

	PR middle-end/79499
	* function.c (thread_prologue_and_epilogue_insns): Determine blocks
	for find_many_sub_basic_blocks bitmap by looking up BLOCK_FOR_INSN
	of first NONDEBUG_INSN_P in each of the split_prologue_seq and
	prologue_seq sequences - if any.

	* gcc.dg/pr79499.c: New test.

From-SVN: r252854

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 69dcc9d6e273ba83d6ba1c51ac94cf36d7d1a4c8..53a5e170e1092bb1b556a6f51c393b38605e682d 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,6 +1,21 @@
 2017-09-15  Jakub Jelinek  <jakub@redhat.com>
 
        Backported from mainline
+       2017-08-08  Richard Biener  <rguenther@suse.de>
+
+       PR middle-end/81766
+       * function.c (thread_prologue_and_epilogue_insns): Restore
+       behavior of always calling find_many_sub_basic_blocks on
+       the inserted prologue.
+
+       2017-08-02  Jakub Jelinek  <jakub@redhat.com>
+
+       PR middle-end/79499
+       * function.c (thread_prologue_and_epilogue_insns): Determine blocks
+       for find_many_sub_basic_blocks bitmap by looking up BLOCK_FOR_INSN
+       of first NONDEBUG_INSN_P in each of the split_prologue_seq and
+       prologue_seq sequences - if any.
+
        2017-06-30  Jakub Jelinek  <jakub@redhat.com>
 
        PR target/81225

diff --git a/gcc/function.c b/gcc/function.c
index 4f2791254e5f3a273387e67198fc86f339e30e03..6942a504127f6f83c56763f51f2425e75fea0ca3 100644 (file)
--- a/gcc/function.c
+++ b/gcc/function.c
@@ -6068,13 +6068,19 @@ thread_prologue_and_epilogue_insns (void)
 
   try_shrink_wrapping (&entry_edge, &bb_flags, prologue_seq);
 
+  rtx_insn *split_prologue_insn = split_prologue_seq;
   if (split_prologue_seq != NULL_RTX)
     {
+      while (split_prologue_insn && !NONDEBUG_INSN_P (split_prologue_insn))
+       split_prologue_insn = NEXT_INSN (split_prologue_insn);
       insert_insn_on_edge (split_prologue_seq, orig_entry_edge);
       inserted = true;
     }
+  rtx_insn *prologue_insn = prologue_seq;
   if (prologue_seq != NULL_RTX)
     {
+      while (prologue_insn && !NONDEBUG_INSN_P (prologue_insn))
+       prologue_insn = NEXT_INSN (prologue_insn);
       insert_insn_on_edge (prologue_seq, entry_edge);
       inserted = true;
     }
@@ -6215,8 +6221,19 @@ epilogue_done:
       commit_edge_insertions ();
 
       /* Look for basic blocks within the prologue insns.  */
+      if (split_prologue_insn
+         && BLOCK_FOR_INSN (split_prologue_insn) == NULL)
+       split_prologue_insn = NULL;
+      if (prologue_insn
+         && BLOCK_FOR_INSN (prologue_insn) == NULL)
+       prologue_insn = NULL;
       blocks = sbitmap_alloc (last_basic_block_for_fn (cfun));
       bitmap_clear (blocks);
+      if (split_prologue_insn)
+       bitmap_set_bit (blocks,
+                       BLOCK_FOR_INSN (split_prologue_insn)->index);
+      if (prologue_insn)
+       bitmap_set_bit (blocks, BLOCK_FOR_INSN (prologue_insn)->index);
       bitmap_set_bit (blocks, entry_edge->dest->index);
       bitmap_set_bit (blocks, orig_entry_edge->dest->index);
       find_many_sub_basic_blocks (blocks);

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 68bb850181228b6d13d6629ac429350f61e340f3..12d910fe41d47ae87ced9520f423a3c1f2813195 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,6 +1,16 @@
 2017-09-15  Jakub Jelinek  <jakub@redhat.com>
 
        Backported from mainline
+       2017-08-08  Richard Biener  <rguenther@suse.de>
+
+       PR middle-end/81766
+       * gcc.target/i386/pr81766.c: New testcase.
+
+       2017-08-02  Jakub Jelinek  <jakub@redhat.com>
+
+       PR middle-end/79499
+       * gcc.dg/pr79499.c: New test.
+
        2017-06-30  Jakub Jelinek  <jakub@redhat.com>
 
        PR target/81225

diff --git a/gcc/testsuite/gcc.dg/pr79499.c b/gcc/testsuite/gcc.dg/pr79499.c
new file mode 100644 (file)
index 0000000..509549f
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr79499.c
@@ -0,0 +1,13 @@
+/* PR middle-end/79499 */
+/* { dg-do compile { target split_stack } } */
+/* { dg-options "-O2 -fsplit-stack -fno-omit-frame-pointer" } */
+
+struct S { struct S *a, *b; };
+
+void
+foo (struct S *x)
+{
+  do
+    x->b = x->a;
+  while (x = x->a);
+}

diff --git a/gcc/testsuite/gcc.target/i386/pr81766.c b/gcc/testsuite/gcc.target/i386/pr81766.c
new file mode 100644 (file)
index 0000000..4bcae7f
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr81766.c
@@ -0,0 +1,5 @@
+/* { dg-do compile } */
+/* { dg-require-effective-target lp64 } */
+/* { dg-options "-O2 -fPIE -mcmodel=large" } */
+
+int main() { return 0; }