gcc/libgcc/config/i386/shadow-stack-unwind.h
H.J. Lu 59a95143dd x86: Add <x86gprintrin.h>
For sources which can't use any vector instructions, <x86intrin.h> and
<immintrin.h> cannot be included for compiler intrinsics:

$ echo "#include <x86intrin.h>" | gcc -S -O2 -mno-sse -mno-mmx -x c -
In file included from /usr/include/stdlib.h:1013,
                 from /usr/lib/gcc/x86_64-redhat-linux/10/include/mm_malloc.h:27,
                 from /usr/lib/gcc/x86_64-redhat-linux/10/include/xmmintrin.h:34,
                 from /usr/lib/gcc/x86_64-redhat-linux/10/include/immintrin.h:29,
                 from /usr/lib/gcc/x86_64-redhat-linux/10/include/x86intrin.h:32,
                 from <stdin>:1:
/usr/include/bits/stdlib-float.h: In function ‘atof’:
/usr/include/bits/stdlib-float.h:26:1: error: SSE register return with SSE disabled
   26 | {
      | ^
$

libgcc/config/i386/shadow-stack-unwind.h has a workaround:

/* NB: We need _get_ssp and _inc_ssp from <cetintrin.h>.  But we can't
   include <x86intrin.h> which ends up including <mm_malloc.h>, which
   includes <stdlib.h> and <errno.h> unconditionally.  But we can't
   include any libc system headers unconditionally from libgcc.  Avoid
   including <mm_malloc.h> here by defining _IMMINTRIN_H_INCLUDED.  */
 #define _IMMINTRIN_H_INCLUDED
 #include <cetintrin.h>
 #undef _IMMINTRIN_H_INCLUDED

Add a standalone intrinsic header file, <x86gprintrin.h>, to provide
integer only intrinsics.  All integer only intrinsics are placed in
<x86gprintrin.h>.  <x86intrin.h> and <immintrin.h> simply include
<x86gprintrin.h>.

gcc/

	PR target/97148
	* config.gcc (extra_headers): Add x86gprintrin.h.
	* config/i386/adxintrin.h: Check _X86GPRINTRIN_H_INCLUDED for
	<x86gprintrin.h>.
	* config/i386/bmi2intrin.h: Likewise.
	* config/i386/bmiintrin.h: Likewise.
	* config/i386/cetintrin.h: Likewise.
	* config/i386/cldemoteintrin.h: Likewise.
	* config/i386/clflushoptintrin.h: Likewise.
	* config/i386/clwbintrin.h: Likewise.
	* config/i386/enqcmdintrin.h: Likewise.
	* config/i386/fxsrintrin.h: Likewise.
	* config/i386/ia32intrin.h: Likewise.
	* config/i386/lwpintrin.h: Likewise.
	* config/i386/lzcntintrin.h: Likewise.
	* config/i386/movdirintrin.h: Likewise.
	* config/i386/pconfigintrin.h: Likewise.
	* config/i386/pkuintrin.h: Likewise.
	* config/i386/rdseedintrin.h: Likewise.
	* config/i386/rtmintrin.h: Likewise.
	* config/i386/serializeintrin.h: Likewise.
	* config/i386/tbmintrin.h: Likewise.
	* config/i386/tsxldtrkintrin.h: Likewise.
	* config/i386/waitpkgintrin.h: Likewise.
	* config/i386/wbnoinvdintrin.h: Likewise.
	* config/i386/xsavecintrin.h: Likewise.
	* config/i386/xsaveintrin.h: Likewise.
	* config/i386/xsaveoptintrin.h: Likewise.
	* config/i386/xsavesintrin.h: Likewise.
	* config/i386/xtestintrin.h: Likewise.
	* config/i386/immintrin.h: Include <x86gprintrin.h> instead of
	<fxsrintrin.h>, <xsaveintrin.h>, <xsaveoptintrin.h>,
	<xsavesintrin.h>, <xsavecintrin.h>, <lzcntintrin.h>,
	<bmiintrin.h>, <bmi2intrin.h>, <xtestintrin.h>, <cetintrin.h>,
	<movdirintrin.h>, <sgxintrin.h, <pconfigintrin.h>,
	<waitpkgintrin.h>, <cldemoteintrin.h>, <enqcmdintrin.h>,
	<serializeintrin.h>, <tsxldtrkintrin.h>, <adxintrin.h>,
	<clwbintrin.h>, <clflushoptintrin.h>, <wbnoinvdintrin.h> and
	<pkuintrin.h>.
	(_wbinvd): Moved to config/i386/x86gprintrin.h.
	(_rdrand16_step): Likewise.
	(_rdrand32_step): Likewise.
	(_rdpid_u32): Likewise.
	(_readfsbase_u32): Likewise.
	(_readfsbase_u64): Likewise.
	(_readgsbase_u32): Likewise.
	(_readgsbase_u64): Likewise.
	(_writefsbase_u32): Likewise.
	(_writefsbase_u64): Likewise.
	(_writegsbase_u32): Likewise.
	(_writegsbase_u64): Likewise.
	(_rdrand64_step): Likewise.
	(_ptwrite64): Likewise.
	(_ptwrite32): Likewise.
	* config/i386/x86gprintrin.h: New file.
	* config/i386/x86intrin.h: Include <x86gprintrin.h>.  Don't
	include <ia32intrin.h>, <lwpintrin.h>, <tbmintrin.h>,
	<popcntintrin.h>, <mwaitxintrin.h> and <clzerointrin.h>.

gcc/testsuite/

	* gcc.target/i386/avx-1.c (__builtin_ia32_lwpval32): New to
	support <lwpintrin.h> included in <x86gprintrin.h>.
	(__builtin_ia32_lwpval64): Likewise.
	(__builtin_ia32_lwpins32): Likewise.
	(__builtin_ia32_lwpins64): Likewise.
	(__builtin_ia32_bextri_u32): New to support <tbmintrin.h>
	included in <x86gprintrin.h>.
	(__builtin_ia32_bextri_u64): Likewise.
	* gcc.target/i386/x86gprintrin-1.c: New test.
	* gcc.target/i386/x86gprintrin-2.c: Likewise.
	* gcc.target/i386/x86gprintrin-3.c: Likewise.
	* gcc.target/i386/x86gprintrin-4.c: Likewise.
	* gcc.target/i386/x86gprintrin-4a.c: Likewise.
	* gcc.target/i386/x86gprintrin-5.c: Likewise.
	* gcc.target/i386/x86gprintrin-5a.c: Likewise.
	* gcc.target/i386/x86gprintrin-5b.c: Likewise.
	* gcc.target/i386/x86gprintrin-6.c: Likewise.

libgcc/

	PR target/97148
	* config/i386/shadow-stack-unwind.h: Include <x86gprintrin.h>
	instead of <cetintrin.h>.
2020-10-09 05:08:41 -07:00

88 lines
2.9 KiB
C

/* _Unwind_Frames_Extra with shadow stack for x86-64 and x86.
Copyright (C) 2017-2020 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.
Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.
You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
<http://www.gnu.org/licenses/>. */
#include <x86gprintrin.h>
/* Unwind the shadow stack for EH. */
#undef _Unwind_Frames_Extra
#define _Unwind_Frames_Extra(x) \
do \
{ \
_Unwind_Word ssp = _get_ssp (); \
if (ssp != 0) \
{ \
_Unwind_Word tmp = (x); \
while (tmp > 255) \
{ \
_inc_ssp (255); \
tmp -= 255; \
} \
_inc_ssp (tmp); \
} \
} \
while (0)
/* Linux CET kernel places a restore token on shadow stack for signal
handler to enhance security. The restore token is 8 byte and aligned
to 8 bytes. It is usually transparent to user programs since kernel
will pop the restore token when signal handler returns. But when an
exception is thrown from a signal handler, now we need to pop the
restore token from shadow stack. For x86-64, we just need to treat
the signal frame as normal frame. For i386, we need to search for
the restore token to check if the original shadow stack is 8 byte
aligned. If the original shadow stack is 8 byte aligned, we just
need to pop 2 slots, one restore token, from shadow stack. Otherwise,
we need to pop 3 slots, one restore token + 4 byte padding, from
shadow stack. */
#ifndef __x86_64__
#undef _Unwind_Frames_Increment
#define _Unwind_Frames_Increment(context, frames) \
if (_Unwind_IsSignalFrame (context)) \
do \
{ \
_Unwind_Word ssp, prev_ssp, token; \
ssp = _get_ssp (); \
if (ssp != 0) \
{ \
/* Align shadow stack pointer to the next \
8 byte aligned boundary. */ \
ssp = (ssp + 4) & ~7; \
do \
{ \
/* Look for a restore token. */ \
token = (*(_Unwind_Word *) (ssp - 8)); \
prev_ssp = token & ~7; \
if (prev_ssp == ssp) \
break; \
ssp += 8; \
} \
while (1); \
frames += (token & 0x4) ? 3 : 2; \
} \
} \
while (0); \
else \
frames++;
#endif