Hi,

The attached patch fixes a problem with pre-decrement store instructions 
on the SH simulator.

The problem can be demonstrated with the following program:

#include <stdio.h>

int
main()
{
	int i[2] = {0,0};
	int *p = &i[1];

	asm ("mov.l %0,@-%0\n" : "+r" (p));

	if ((int*)i[0] == &i[1])
	  printf ("PASS: Value Correct.\n");
	else
	  printf ("FAIL: Incorrect value written.\n");

	return 0;
}

The issue is that, when both operands use the same register, the *value* 
to be stored is decremented, but only the *address* of the store should 
have been decremented. I.e. in the example, it is supposed to store "p" 
at "p - 4", but actually stores "p - 4" at "p - 4".

Note that GCC has a similar error which means that the two work together 
(probably not an accident), but the binaries may not work on real 
silicon. I think a patch for this problem will be submitted to GCC 
sometime soon.

:ADDPATCH sh sim:

Unfortunately, I can't test it on the latest GDB because CVS isn't 
accessible (corporate IT issue), but I'm fairly sure it works in the 
sources I do have. For the same reason, I'll have to ask somebody else 
to do the commit for me.

Thanks

Andrew Stubbs