From: Ivan Maidanski <ivmai@mail.ru>
Date: Fri, 20 Jan 2017 00:03:54 +0000 (+0300)
Subject: Add assertion that double-wide CAS target is aligned (msftc/x86[_64])
X-Git-Tag: v7.4.6~51
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=82258fade80917f1c9872a75f8e16a7af9bf06a3;p=libatomic_ops

Add assertion that double-wide CAS target is aligned (msftc/x86[_64])

* src/atomic_ops/sysdeps/msftc/x86.h [AO_ASSUME_VISTA]
(AO_double_compare_and_swap_full): Add assert() that addr pointer is
aligned according to the size of AO_double_t.
* src/atomic_ops/sysdeps/msftc/x86_64.h [AO_CMPXCHG16B_AVAILABLE
&& _MSC_VER>=1500] (AO_compare_double_and_swap_double_full): Likewise.
---

diff --git a/src/atomic_ops/sysdeps/msftc/x86.h b/src/atomic_ops/sysdeps/msftc/x86.h
index 7c2995a..1f87a12 100644
--- a/src/atomic_ops/sysdeps/msftc/x86.h
+++ b/src/atomic_ops/sysdeps/msftc/x86.h
@@ -124,6 +124,7 @@ AO_test_and_set_full(volatile AO_TS_t *addr)
   AO_double_compare_and_swap_full(volatile AO_double_t *addr,
                                   AO_double_t old_val, AO_double_t new_val)
   {
+    assert(((size_t)addr & (sizeof(AO_double_t) - 1)) == 0);
     return (double_ptr_storage)_InterlockedCompareExchange64(
                                         (__int64 volatile *)addr,
                                         new_val.AO_whole /* exchange */,
diff --git a/src/atomic_ops/sysdeps/msftc/x86_64.h b/src/atomic_ops/sysdeps/msftc/x86_64.h
index b4b0a3c..2bbc3fd 100644
--- a/src/atomic_ops/sysdeps/msftc/x86_64.h
+++ b/src/atomic_ops/sysdeps/msftc/x86_64.h
@@ -159,6 +159,8 @@ AO_compare_double_and_swap_double_full(volatile AO_double_t *addr,
                                        AO_t new_val1, AO_t new_val2)
 {
    __int64 comparandResult[2];
+
+   assert(((size_t)addr & (sizeof(AO_double_t) - 1)) == 0);
    comparandResult[0] = old_val1; /* low */
    comparandResult[1] = old_val2; /* high */
    return _InterlockedCompareExchange128((volatile __int64 *)addr,