[Open64-devel] Re: Open64/ORC as a source-to-source compiler (redux)

[Marc Gonzalez-S. <mar...@in...>]

Marc Gonzalez-Sigler wrote:

> Take 183.equake, a single-file C program, from SPECfp2000 for example,
> 
> $ orcc -fe -keep quake.c
> $ w2c quake.B
> whirl2c translates quake.B into quake.w2c.h and quake.w2c.c, based on 
> source quake.c
> $ orcc -I. quake.w2c.c -lm (or gcc -I. quake.w2c.c -lm)
> $ a.out < inp.in 1> stdout
> $ head stdout
> 3135: 4.60e+141 -1.40e+143 1.45e+142
> 3135: 4.60e+141 -1.40e+143 1.45e+142
> 3135: nan nan nan
> 3135: nan nan nan
> 
> As you can see, the output is incorrect.
> 
> Has anybody tested whirl2c and whirl2f with the SPECfp2000 benchmarks? 
> Did it work for you? (Perhaps I built the compiler incorrectly.)

$ cat testcase.c
struct foo { int x; int y[3]; } bar;

int main(void)
{
   bar.y[1] = 666;
   return 0;
}

$ orcc -fe -keep testcase.c ; w2c testcase.B
whirl2c translates testcase.B into testcase.w2c.h and testcase.w2c.c, 
based on source testcase.c
!!! DevWarn during W2C Initialization: Should use ST_pu_type instead
!!! DevWarn during WHIRL To C: Count limit reached on the following DevWarn:
!!! DevWarn during WHIRL To C: Should use ST_pu_type instead
!!! DevWarn during WHIRL To C: Rehashing TY pointer map -- this should 
NOT happen often

$ cat testcase.w2c.c
[...]
_INT32 main()
{
   (*(_INT32 *)(&((struct foo__0 *)(((_INT8 *) & bar) + 4LL))[1])) = 666;
   return 0;
} /* main */

Let char *p = &(bar.y)

((_INT8 *) & bar) + 4LL == p (so far, so good)

(*(_INT32 *)(&((struct foo__0 *)p)[1])) = 666;

Then, p is incorrectly cast to a 'struct foo' pointer.

Let struct foo *WRONG = (struct foo *)p

(*(_INT32 *)(&WRONG[1])) = 666;

&WRONG[1] == p + 1*sizeof(struct foo)

We are now pointing *outside* bar :-)

I will try to fix it.

-- 
Regards, Marc