include/exec/memop.h

8  * See the COPYING file in the top-level directory.
15 #include "qemu/host-utils.h"
28     MO_SIGN  = 0x08,   /* Sign-extended, otherwise zero-extended.  */
49      * do_unaligned_access hook if the guest address is not aligned.
51      * Some architectures (e.g. ARMv8) need the address which is aligned
53      * Some architectures (e.g. SPARCv9) need an address which is aligned,
59      * - unaligned access permitted (MO_UNALN).
60      * - an alignment to the size of an access (MO_ALIGN);
61      * - an alignment to a specified size, which may be more or less than
77      * MO_ATOM_IFALIGN: the operation must be single-copy atomic if it
78      *    is aligned; if unaligned there is no atomicity.
80      *    be a pair of half-sized operations which are packed together
81      *    for convenience, with single-copy atomicity on each half if
82      *    the half is aligned.
83      *    This is the atomicity e.g. of Arm pre-FEAT_LSE2 LDP.
84      * MO_ATOM_WITHIN16: the operation is single-copy atomic, even if it
85      *    is unaligned, so long as it does not cross a 16-byte boundary;
86      *    if it crosses a 16-byte boundary there is no atomicity.
88      * MO_ATOM_WITHIN16_PAIR: the entire operation is single-copy atomic,
89      *    if it happens to be within a 16-byte boundary, otherwise it
90      *    devolves to a pair of half-sized MO_ATOM_WITHIN16 operations.
91      *    Depending on alignment, one or both will be single-copy atomic.
93      * MO_ATOM_SUBALIGN: the operation is single-copy atomic by parts
94      *    by the alignment.  E.g. if the address is 0 mod 4, then each
95      *    4-byte subobject is single-copy atomic.
99      * Note the default (i.e. 0) value is single-copy atomic to the
100      * size of the operation, if aligned.  This retains the behaviour
162     assert((size & (size - 1)) == 0 && size >= 1 && size <= 8);  in size_memop()
206         size = size ? size - 1 : 0;  in memop_atomicity_bits()