| Message ID | 1456431555-14182-3-git-send-email-adhemerval.zanella@linaro.org |
|---|---|
| State | New |
| Headers | show |
On 25 Feb 2016 17:19, Adhemerval Zanella wrote: > --- a/sysdeps/unix/sysv/linux/sysdep.h > +++ b/sysdeps/unix/sysv/linux/sysdep.h > > +/* Provide a dummy argument that can be used to force register > + alignment for register pairs if required by the syscall ABI. */ > +#ifdef __ASSUME_ALIGNED_REGISTER_PAIRS > +#define __ALIGNMENT_ARG 0, > +#define __ALIGNMENT_COUNT(a,b) b > +#else > +#define __ALIGNMENT_ARG > +#define __ALIGNMENT_COUNT(a,b) a > +#endif while not a new issue, should the return be parenthesized ? i.e. (b) and (a) ? -mike
On 10-04-2016 01:14, Mike Frysinger wrote: > On 25 Feb 2016 17:19, Adhemerval Zanella wrote: >> --- a/sysdeps/unix/sysv/linux/sysdep.h >> +++ b/sysdeps/unix/sysv/linux/sysdep.h >> >> +/* Provide a dummy argument that can be used to force register >> + alignment for register pairs if required by the syscall ABI. */ >> +#ifdef __ASSUME_ALIGNED_REGISTER_PAIRS >> +#define __ALIGNMENT_ARG 0, >> +#define __ALIGNMENT_COUNT(a,b) b >> +#else >> +#define __ALIGNMENT_ARG >> +#define __ALIGNMENT_COUNT(a,b) a >> +#endif > > while not a new issue, should the return be parenthesized ? > i.e. (b) and (a) ? > -mike > I will change that, thanks.
On 11-04-2016 09:17, Adhemerval Zanella wrote: > > > On 10-04-2016 01:14, Mike Frysinger wrote: >> On 25 Feb 2016 17:19, Adhemerval Zanella wrote: >>> --- a/sysdeps/unix/sysv/linux/sysdep.h >>> +++ b/sysdeps/unix/sysv/linux/sysdep.h >>> >>> +/* Provide a dummy argument that can be used to force register >>> + alignment for register pairs if required by the syscall ABI. */ >>> +#ifdef __ASSUME_ALIGNED_REGISTER_PAIRS >>> +#define __ALIGNMENT_ARG 0, >>> +#define __ALIGNMENT_COUNT(a,b) b >>> +#else >>> +#define __ALIGNMENT_ARG >>> +#define __ALIGNMENT_COUNT(a,b) a >>> +#endif >> >> while not a new issue, should the return be parenthesized ? >> i.e. (b) and (a) ? >> -mike >> > > I will change that, thanks. In fact we can not change it: some functions uses the define as __ALIGNMENT_COUNT (3, 4) and some ports uses to correct select the LOAD_ARGS_{3,4} in syscall generation (nios2). Using parenthesis leads it to evaluate as LOAD_ARGS_(3) and this issuing a build issue (this can be fixed I think, but it is not the idea of this patch).
diff --git a/sysdeps/unix/sysv/linux/generic/sysdep.h b/sysdeps/unix/sysv/linux/generic/sysdep.h index 4f2c65d..b0422ff 100644 --- a/sysdeps/unix/sysv/linux/generic/sysdep.h +++ b/sysdeps/unix/sysv/linux/generic/sysdep.h @@ -31,13 +31,3 @@ #define __NR_pread __NR_pread64 #define __NR_pwrite __NR_pwrite64 #endif - -/* Provide a dummy argument that can be used to force register - alignment for register pairs if required by the syscall ABI. */ -#ifdef __ASSUME_ALIGNED_REGISTER_PAIRS -#define __ALIGNMENT_ARG 0, -#define __ALIGNMENT_COUNT(a,b) b -#else -#define __ALIGNMENT_ARG -#define __ALIGNMENT_COUNT(a,b) a -#endif diff --git a/sysdeps/unix/sysv/linux/mips/kernel-features.h b/sysdeps/unix/sysv/linux/mips/kernel-features.h index ea6a914..17ab696 100644 --- a/sysdeps/unix/sysv/linux/mips/kernel-features.h +++ b/sysdeps/unix/sysv/linux/mips/kernel-features.h @@ -53,3 +53,9 @@ #if _MIPS_SIM == _ABIO32 # define __ASSUME_ALIGNED_REGISTER_PAIRS 1 #endif + +/* Define that mips64-n32 is a ILP32 ABI to set the correct interface to + pass 64-bits values through syscalls. */ +#if _MIPS_SIM == _ABIN32 +# define __ASSUME_WORDSIZE64_ILP32 1 +#endif diff --git a/sysdeps/unix/sysv/linux/sysdep.h b/sysdeps/unix/sysv/linux/sysdep.h index c98fc3a..5ee73d5 100644 --- a/sysdeps/unix/sysv/linux/sysdep.h +++ b/sysdeps/unix/sysv/linux/sysdep.h @@ -15,6 +15,8 @@ License along with the GNU C Library; if not, see <http://www.gnu.org/licenses/>. */ +#include <bits/wordsize.h> + /* Set error number and return -1. A target may choose to return the internal function, __syscall_error, which sets errno and returns -1. We use -1l, instead of -1, so that it can be casted to (void *). */ @@ -23,3 +25,24 @@ __set_errno (err); \ -1l; \ }) + +/* Provide a dummy argument that can be used to force register + alignment for register pairs if required by the syscall ABI. */ +#ifdef __ASSUME_ALIGNED_REGISTER_PAIRS +#define __ALIGNMENT_ARG 0, +#define __ALIGNMENT_COUNT(a,b) b +#else +#define __ALIGNMENT_ARG +#define __ALIGNMENT_COUNT(a,b) a +#endif + +/* Provide a common macro to pass 64-bit value on syscalls. */ +#if __WORDSIZE == 64 || defined __ASSUME_WORDSIZE64_ILP32 +# define SYSCALL_LL(val) (val) +# define SYSCALL_LL64(val) (val) +#else +#define SYSCALL_LL(val) \ + __LONG_LONG_PAIR ((val) >> 31, __val) +#define SYSCALL_LL64(val) \ + __LONG_LONG_PAIR ((long) ((val) >> 32), (long) ((val) & 0xffffffff)) +#endif diff --git a/sysdeps/unix/sysv/linux/x86_64/kernel-features.h b/sysdeps/unix/sysv/linux/x86_64/kernel-features.h index 0b84f11..569e8f8 100644 --- a/sysdeps/unix/sysv/linux/x86_64/kernel-features.h +++ b/sysdeps/unix/sysv/linux/x86_64/kernel-features.h @@ -35,4 +35,10 @@ # define __ASSUME_GETCPU_SYSCALL 1 #endif +/* Define that x32 is a ILP32 ABI to set the correct interface to pass + 64-bits values through syscalls. */ +#ifdef __ILP32__ +# define __ASSUME_WORDSIZE64_ILP32 1 +#endif + #include_next <kernel-features.h>
From: Adhemerval Zanella <adhemerval.zanella@linaro.com> This patch add three new macros (SYSCALL_LL, SYSCALL_LL64, and __ASSUME_WORDSIZE64_ILP32) to use along with off_t and off64_t argument syscalls. The rationale for this change is: 1. Remove multiple implementations for the same syscall for different architectures (for instance, pread have 6 different implementations). 2. Also remove the requirement to use syscall wrappers for cancellable entrypoints. The macro usage should be used along __ALIGNMENT_ARG to follow ABI constrains for architecture where it applies. For instance, pread can be rewritten as: return SYSCALL_CANCEL (pread, fd, buf, count, __ALIGNMENT_ARG SYSCALL_LL (offset)); Another macro, SYSCALL_LL64, is provided for off64_t. The macro __ASSUME_WORDSIZE64_ILP32 is used by the ABI to define is uses 64-bit register even if ABI is ILP32 (for instance x32 and mips64-n32). The changes itself are not currently used in any implementation, so no code change is expected. * sysdeps/unix/sysv/linux/generic/sysdep.h (__ALIGNMENT_ARG): Move definition. (__ALIGNMENT_COUNT): Likewise. * sysdeps/unix/sysv/linux/sysdep.h (__ALIGNMENT_ARG): To here. (__ALIGNMENT_COUNT): Likewise. (SYSCALL_LL): New define. (SYSCALL_LL64): Likewise. * sysdeps/unix/sysv/linux/mips/kernel-features.h: [_MIPS_SIM == _ABIO32] (__ASSUME_WORDSIZE64_ILP32): Define. * sysdeps/unix/sysv/linux/x86_64/kernel-features.h: [ILP32] (__ASUME_WORDSIZE64_ILP32): Likewise. --- sysdeps/unix/sysv/linux/generic/sysdep.h | 10 ---------- sysdeps/unix/sysv/linux/mips/kernel-features.h | 6 ++++++ sysdeps/unix/sysv/linux/sysdep.h | 23 +++++++++++++++++++++++ sysdeps/unix/sysv/linux/x86_64/kernel-features.h | 6 ++++++ 5 files changed, 47 insertions(+), 10 deletions(-)