------- Comment #1 from nickc at redhat dot com 2010-07-22 09:42 -------
Hi Kazuhiro-san,
This is not a bug, it is the expected behaviour.
What is happening is that the return value from func() is being promoted to
"signed int" (and not "unsigned int" as you might expect). Thus since the
MOV.B instruction performs a sign extension it is a sufficient instruction for
the load operation.
Note - if you try using the result of calling func() then you will see a zero
extension being performed. Eg:
int bar (int a) { return a < func(); }
results in:
mov.L #_uA, r14
movu.B [r14], r14
cmp r1, r14
sclt.L r1
rts
with inlining, or:
push.l r7
mov.L r1, r7
bsr _func
movu.B r1, r1
cmp r7, r1
sclt.L r1
rtsd #4, r7-r7
without.
Cheers
Nick Clifton
PS. See section 6.3.1.1 of the ISO C99 standard for more information about this
behaviour
--
nickc at redhat dot com changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |nickc at redhat dot com
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45000
