This is the mail archive of the gdb-patches@sources.redhat.com mailing list for the GDB project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]

Re: [RFA] info breakpoints: handle 64-bit addresses


Ed Satterthwaite wrote:
> 
> As written, this patch has a slightly unfortunate side effect for MIPS
> targets.
> 
> Michael Snyder <msnyder@cygnus.com> wrote
> 
> > 2001-03-14  Michael Snyder  <msnyder@redhat.com>
> >
> >         * breakpoint.c (print_one_breakpoint): Handle 64-bit addresses.
> 
> In the code below, b->address is a CORE_ADDR, which is 64 bits when
> gdb is configured to support 64-bit MIPS targets.  TARGET_ADDR_BIT is
> implicitly set in mips-tdep.c according to the ABI deduced from the
> object file.  For 32-bit or unknown ABI's, that will be 32.  In the
> MIPS architecture, a 64-bit CPU sign-extends 32-bit addresses.
> 
> At least on some hosts, the output conversion is done by sprintf.
> Thus 32-bit addresses with bit 31 clear will print as 8 hex digits,
> while those with bit 31 set (e.g., kseg0 and kseg1) will spill into 16
> hex digits, thereby spoiling the intended column alignment.
> 
> Here's a possible alternative for the first arm of the new
> conditional.  It's similar to usage in mips-tdep.c.  It avoids the
> cast to unsigned long in the original code but does assume ANSI C.
> 
>    tmp = longest_local_hex_string_custom ((b->address
>                                            & (CORE_ADDR) 0xffffffff),
>                                           "08l");

Ah -- OK, this is reasonable.  Thanks for the suggestion.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]