[Bug target/32577] [SH] static inline attribute causes stack overflow

[saito at densan dot co dot jp]

------- Comment #2 from saito at densan dot co dot jp  2007-07-23 01:23 -------
How about following testcase. 

I list the value which moves current sp as to some architectures.
In the following case, listed value is 24.

>         add     #-24,r15     <-- stack grows down

With the result that only gcc-4.2.0 for sh4 accumulates the stack space for
inlined variables. Actually, I need to spread the stack size for sh-linux's
kernel-thread from 0x2000 byte to 0x4000 byte, although I specify optimization
option(-O2). Gcc-4.1.2 does not have this problem.

-testcase--------------------------------------------------
struct xxx {
    int x;
    int y;
};

static inline __attribute__((always_inline)) int add(int x, int y)
{
    struct xxx xxx;
    xxx.x = x;
    xxx.y = y;
    dummy(&xxx);
    return x + y;
}

int x, y;

main(int ac, char** av)
{
    x = add(x, y);      /* count of add is one */
    return x;
}
-end testcase----------------------------------------------

compiling options: gcc test.c -O2 -S

case of gcc-4.2.0
-----------------------------------------------------------
count of add     |      1      2      4      8     16
-------------------------------------------------------------
the value    sh4 |      8     16     24     40     68
             ppc |     48     64     64     64     64
            i686 |     16     16     16     16     16

case of gcc-4.1.2
-----------------------------------------------------------
the value    sh4 |      8      8      8      8      8


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32577