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authorH.J. Lu <hjl.tools@gmail.com>2021-05-23 09:15:52 -0700
committerH.J. Lu <hjl.tools@gmail.com>2021-05-24 07:42:12 -0700
commit79aec841029c160a85f46564f8bad132af008e30 (patch)
treeaf636da51359f8ff5d18d700b51067e1196b37c0 /sysdeps/powerpc/tst-stack-align.h
parent1b992204f68af851e905c16016756fd4421e1934 (diff)
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Properly check stack alignment [BZ #27901]
1. Replace

if ((((uintptr_t) &_d) & (__alignof (double) - 1)) != 0)

which may be optimized out by compiler, with

int
__attribute__ ((weak, noclone, noinline))
is_aligned (void *p, int align)
{
  return (((uintptr_t) p) & (align - 1)) != 0;
}

2. Add TEST_STACK_ALIGN_INIT to TEST_STACK_ALIGN.
3. Add a common TEST_STACK_ALIGN_INIT to check 16-byte stack alignment
for both i386 and x86-64.
4. Update powerpc to use TEST_STACK_ALIGN_INIT.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Diffstat (limited to 'sysdeps/powerpc/tst-stack-align.h')
-rw-r--r--sysdeps/powerpc/tst-stack-align.h27
1 files changed, 7 insertions, 20 deletions
diff --git a/sysdeps/powerpc/tst-stack-align.h b/sysdeps/powerpc/tst-stack-align.h
index 2b4a3671b4..be055b0385 100644
--- a/sysdeps/powerpc/tst-stack-align.h
+++ b/sysdeps/powerpc/tst-stack-align.h
@@ -1,4 +1,5 @@
-/* Copyright (C) 2005-2021 Free Software Foundation, Inc.
+/* Check stack alignment.  PowerPC version.
+   Copyright (C) 2005-2021 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -15,10 +16,7 @@
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#include <stdio.h>
-#include <stdint.h>
-
-#define TEST_STACK_ALIGN() \
+#define TEST_STACK_ALIGN_INIT() \
   ({									     \
     /* Altivec __vector int etc. needs 16byte aligned stack.		     \
        Instead of using altivec.h here, use aligned attribute instead.  */   \
@@ -27,20 +25,9 @@
         int _i __attribute__((aligned (16)));				     \
 	int _j[3];							     \
       } _s = { ._i = 18, ._j[0] = 19, ._j[1] = 20, ._j[2] = 21 };	     \
-    double _d = 12.0;							     \
-    long double _ld = 15.0;						     \
-    int _ret = 0;							     \
     printf ("__vector int:  { %d, %d, %d, %d } %p %zu\n", _s._i, _s._j[0],   \
             _s._j[1], _s._j[2], &_s, __alignof (_s));			     \
-    if ((((uintptr_t) &_s) & (__alignof (_s) - 1)) != 0)		     \
-      _ret = 1;								     \
-									     \
-    printf ("double:  %g %p %zu\n", _d, &_d, __alignof (double));	     \
-    if ((((uintptr_t) &_d) & (__alignof (double) - 1)) != 0)		     \
-      _ret = 1;								     \
-									     \
-    printf ("ldouble: %Lg %p %zu\n", _ld, &_ld, __alignof (long double));    \
-    if ((((uintptr_t) &_ld) & (__alignof (long double) - 1)) != 0)	     \
-      _ret = 1;								     \
-    _ret;								     \
-    })
+    is_aligned (&_s, __alignof (_s));					     \
+   })
+
+#include_next <tst-stack-align.h>