| Message ID | 1385488365-12372-1-git-send-email-matthew.leach@arm.com |
|---|---|
| State | New |
| Headers | show |
On Tue, Nov 26, 2013 at 9:52 AM, Matthew Leach <matthew.leach@arm.com> wrote: > Hi, > > When unwinding the stack, the unwind code checks for two opcodes that > denote a registrations of a signal handler. This is broken on BE as > the opcodes will be in the wrong byte-order as insns are always LE. > > Add the correct checks when compiling for AArch64 big endian. > > This has been tested with the glibc test "tst-backtrace4" and passes > with this patch applied. > > Please note that I don't have commit access, if this is OK could > someone merge it for me? > > Thanks, > Matt Leach > > libgcc/ > 2013-11-26 Matthew Leach <matthew.leach@arm.com> > > * config/aarch64/linux-unwind.h (aarch64_fallback_frame_state): > Check for correct opcodes on BE. > > diff --git a/libgcc/config/aarch64/linux-unwind.h b/libgcc/config/aarch64/linux-unwind.h > index fde4d14..9f30b87 100644 > --- a/libgcc/config/aarch64/linux-unwind.h > +++ b/libgcc/config/aarch64/linux-unwind.h > @@ -25,6 +25,14 @@ > #include <signal.h> > #include <sys/ucontext.h> > > +#if __AARCH64EB__ > +#define MOVZ_X8_8B 0x681180d2 > +#define SVC_0 0x010000d4 > +#else > +#define MOVZ_X8_8B 0xd2801168 > +#define SVC_0 0xd4000001 > +#endif I think this should have a comment about the byte-order of instructions so it is easier to understand why they are different between big and little-endian. Thanks, Andrew Pinski > + > #define MD_FALLBACK_FRAME_STATE_FOR aarch64_fallback_frame_state > > static _Unwind_Reason_Code > @@ -55,7 +63,7 @@ aarch64_fallback_frame_state (struct _Unwind_Context *context, > 0xd2801168 movz x8, #0x8b > 0xd4000001 svc 0x0 > */ > - if (pc[0] != 0xd2801168 || pc[1] != 0xd4000001) > + if (pc[0] != MOVZ_X8_8B || pc[1] != SVC_0) > { > return _URC_END_OF_STACK; > } > -- > 1.7.9.5 > >
diff --git a/libgcc/config/aarch64/linux-unwind.h b/libgcc/config/aarch64/linux-unwind.h index fde4d14..9f30b87 100644 --- a/libgcc/config/aarch64/linux-unwind.h +++ b/libgcc/config/aarch64/linux-unwind.h @@ -25,6 +25,14 @@ #include <signal.h> #include <sys/ucontext.h> +#if __AARCH64EB__ +#define MOVZ_X8_8B 0x681180d2 +#define SVC_0 0x010000d4 +#else +#define MOVZ_X8_8B 0xd2801168 +#define SVC_0 0xd4000001 +#endif + #define MD_FALLBACK_FRAME_STATE_FOR aarch64_fallback_frame_state static _Unwind_Reason_Code @@ -55,7 +63,7 @@ aarch64_fallback_frame_state (struct _Unwind_Context *context, 0xd2801168 movz x8, #0x8b 0xd4000001 svc 0x0 */ - if (pc[0] != 0xd2801168 || pc[1] != 0xd4000001) + if (pc[0] != MOVZ_X8_8B || pc[1] != SVC_0) { return _URC_END_OF_STACK; }