There have been several PRs that all boil down to the fact that SSE
insns segfault since one of their operands isn't sufficiently aligned.
Initially, it seemed that only Solaris 9/x86 wass affected, and the issue
was fixed on the 4.9 branch (the last supported on Solaris 9) by
enabling -mstackrealign by default:
Only assume 4-byte stack alignment on Solaris 9/x86 (PR libgomp/60107)
http://gcc.gnu.org/ml/gcc-patches/2014-02/msg00662.html
Now PRs target/61949 and target/62281 show the same issue on 32-bit
Solaris 10/x86, and I've received confirmation that Solaris indeed only
guarantees 4-byte stack alignment as required by the i386 psABI. Given
that, the following patch generalizes the patch above.
Bootstrapped without regressions on i386-pc-solaris2.1[012]. I'm
applying it to mainline now, although I don't yet understand why the
testcases only fail on Solaris 10. Given that this is a wrong-code bug,
I'm going to apply it to the gcc-5 and gcc-4.9 branches within a week.
Rainer
2016-02-29 Rainer Orth <r...@cebitec.uni-bielefeld.de>
PR target/62281
* config/i386/sol2.h (STACK_REALIGN_DEFAULT): Define.
# HG changeset patch
# Parent fe2aecc6db984d0da6866189364e4fa9c5021495
Only assume 4-byte stack alignment on Solaris/x86 (PR target/62281)
diff --git a/gcc/config/i386/sol2.h b/gcc/config/i386/sol2.h
--- a/gcc/config/i386/sol2.h
+++ b/gcc/config/i386/sol2.h
@@ -21,6 +21,11 @@ along with GCC; see the file COPYING3.
#define SUBTARGET_OPTIMIZATION_OPTIONS \
{ OPT_LEVELS_1_PLUS, OPT_momit_leaf_frame_pointer, NULL, 1 }
+/* 32-bit Solaris/x86 only guarantees 4-byte stack alignment as required by
+ the i386 psABI, so realign it as necessary for SSE instructions. */
+#undef STACK_REALIGN_DEFAULT
+#define STACK_REALIGN_DEFAULT (TARGET_64BIT ? 0 : 1)
+
/* Old versions of the Solaris assembler can not handle the difference of
labels in different sections, so force DW_EH_PE_datarel if so. */
#ifndef HAVE_AS_IX86_DIFF_SECT_DELTA
2016-02-29 Rainer Orth <r...@cebitec.uni-bielefeld.de>
Backport from mainline
PR target/62281
* config/i386/sol2.h (STACK_REALIGN_DEFAULT): Define.
Revert:
2014-02-11 Rainer Orth <r...@cebitec.uni-bielefeld.de>
PR libgomp/60107
* config/i386/sol2-9.h: New file.
* config.gcc (i[34567]86-*-solaris2* | x86_64-*-solaris2.1[0-9]*,
*-*-solaris2.9*): Use it.
# HG changeset patch
# Parent 20345b38cd619b11e097531603ee5eb0d7f56835
Only assume 4-byte stack alignment on Solaris/x86 (PR target/62281)
diff --git a/gcc/config.gcc b/gcc/config.gcc
--- a/gcc/config.gcc
+++ b/gcc/config.gcc
@@ -1542,9 +1542,6 @@ i[34567]86-*-solaris2* | x86_64-*-solari
esac
with_tune_32=${with_tune_32:-generic}
case ${target} in
- *-*-solaris2.9*)
- tm_file="${tm_file} i386/sol2-9.h"
- ;;
*-*-solaris2.1[0-9]*)
tm_file="${tm_file} i386/x86-64.h i386/sol2-bi.h sol2-bi.h"
tm_defines="${tm_defines} TARGET_BI_ARCH=1"
diff --git a/gcc/config/i386/sol2-9.h b/gcc/config/i386/sol2-9.h
deleted file mode 100644
--- a/gcc/config/i386/sol2-9.h
+++ /dev/null
@@ -1,23 +0,0 @@
-/* Target definitions for GCC for Intel 80386 running Solaris 9
- Copyright (C) 2014 Free Software Foundation, Inc.
-
-This file is part of GCC.
-
-GCC is free software; you can redistribute it and/or modify
-it under the terms of the GNU General Public License as published by
-the Free Software Foundation; either version 3, or (at your option)
-any later version.
-
-GCC is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-GNU General Public License for more details.
-
-You should have received a copy of the GNU General Public License
-along with GCC; see the file COPYING3. If not see
-<http://www.gnu.org/licenses/>. */
-
-/* Solaris 9 only guarantees 4-byte stack alignment as required by the i386
- psABI, so realign it as necessary for SSE instructions. */
-#undef STACK_REALIGN_DEFAULT
-#define STACK_REALIGN_DEFAULT 1
diff --git a/gcc/config/i386/sol2.h b/gcc/config/i386/sol2.h
--- a/gcc/config/i386/sol2.h
+++ b/gcc/config/i386/sol2.h
@@ -25,6 +25,11 @@ along with GCC; see the file COPYING3.
#define TARGET_SUBTARGET_DEFAULT \
(MASK_80387 | MASK_IEEE_FP | MASK_FLOAT_RETURNS | MASK_VECT8_RETURNS)
+/* 32-bit Solaris/x86 only guarantees 4-byte stack alignment as required by
+ the i386 psABI, so realign it as necessary for SSE instructions. */
+#undef STACK_REALIGN_DEFAULT
+#define STACK_REALIGN_DEFAULT (TARGET_64BIT ? 0 : 1)
+
/* Old versions of the Solaris assembler can not handle the difference of
labels in different sections, so force DW_EH_PE_datarel. */
#undef ASM_PREFERRED_EH_DATA_FORMAT
--
-----------------------------------------------------------------------------
Rainer Orth, Center for Biotechnology, Bielefeld University
