Updated the extra parameter to __atomic_{is,always}_lock_free , and bkoz
noted that the __atomic_compare_exchange documentation did not document
the 'weak' parameter.
Fixed as such, seems to format fine. OK for mainline?
Andrew
PR c/52190
* doc/extend.texi : Update comments for __atomic_compare_exchange and
__atomic_{is,always}_lock_free.
Index: doc/extend.texi
===================================================================
*** doc/extend.texi (revision 183969)
--- doc/extend.texi (working copy)
*************** This built-in function implements an ato
*** 7146,7152 ****
This compares the contents of @code{*@var{ptr}} with the contents of
@code{*@var{expected}} and if equal, writes @var{desired} into
@code{*@var{ptr}}. If they are not equal, the current contents of
! @code{*@var{ptr}} is written into @code{*@var{expected}}.
True is returned if @code{*@var{desired}} is written into
@code{*@var{ptr}} and the execution is considered to conform to the
--- 7146,7155 ----
This compares the contents of @code{*@var{ptr}} with the contents of
@code{*@var{expected}} and if equal, writes @var{desired} into
@code{*@var{ptr}}. If they are not equal, the current contents of
! @code{*@var{ptr}} is written into @code{*@var{expected}}. @var{weak} is true
! for weak compare_exchange, and false for the strong variation. Many targets
! only offer the strong variation and ignore the parameter. When in doubt, use
! the strong variation.
True is returned if @code{*@var{desired}} is written into
@code{*@var{ptr}} and the execution is considered to conform to the
*************** All memory orders are valid.
*** 7242,7268 ****
@end deftypefn
! @deftypefn {Built-in Function} bool __atomic_always_lock_free (size_t size)
! This built-in function returns true if objects of size bytes will always
! generate lock free atomic instructions for the target architecture.
! Otherwise false is returned.
! size must resolve to a compile time constant.
@smallexample
! if (_atomic_always_lock_free (sizeof (long long)))
@end smallexample
@end deftypefn
! @deftypefn {Built-in Function} bool __atomic_is_lock_free (size_t size)
! This built-in function returns true if objects of size bytes will always
generate lock free atomic instructions for the target architecture. If
it is not known to be lock free a call is made to a runtime routine named
@code{__atomic_is_lock_free}.
@end deftypefn
@node Object Size Checking
--- 7245,7276 ----
@end deftypefn
! @deftypefn {Built-in Function} bool __atomic_always_lock_free (size_t size,
void *ptr)
! This built-in function returns true if objects of @var{size} bytes will always
! generate lock free atomic instructions for the target architecture.
! @var{size} must resolve to a compile time constant and the result also
resolves to compile time constant.
! @var{ptr} is an optional pointer to the object which may be used to determine
! alignment. A value of 0 indicates typical alignment should be used. The
! compiler may also ignore this parameter.
@smallexample
! if (_atomic_always_lock_free (sizeof (long long), 0))
@end smallexample
@end deftypefn
! @deftypefn {Built-in Function} bool __atomic_is_lock_free (size_t size, void
*ptr)
! This built-in function returns true if objects of @var{size} bytes will always
generate lock free atomic instructions for the target architecture. If
it is not known to be lock free a call is made to a runtime routine named
@code{__atomic_is_lock_free}.
+ @var{ptr} is an optional pointer to the object which may be used to determine
+ alignment. A value of 0 indicates typical alignment should be used. The
+ compiler may also ignore this parameter.
@end deftypefn
@node Object Size Checking
