Flavio Cruz, le mer. 28 févr. 2024 22:59:09 -0500, a ecrit:
> Tested with some simple toy examples where an exception is thrown in the
> signal handler.
>
> libgcc/ChangeLog:
> * config/i386/gnu-unwind.h: Support unwinding x86_64 signal frames.
>
> Signed-off-by: Flavio Cruz <flavioc...@gmail.com>
Reviewed-by: Samuel Thibault <samuel.thiba...@ens-lyon.org>
Thanks!!
> ---
> libgcc/config/i386/gnu-unwind.h | 97 ++++++++++++++++++++++++++++++++-
> 1 file changed, 94 insertions(+), 3 deletions(-)
>
> diff --git a/libgcc/config/i386/gnu-unwind.h b/libgcc/config/i386/gnu-unwind.h
> index 0751b5593d4..02b060ab4a5 100644
> --- a/libgcc/config/i386/gnu-unwind.h
> +++ b/libgcc/config/i386/gnu-unwind.h
> @@ -32,9 +32,100 @@ see the files COPYING3 and COPYING.RUNTIME respectively.
> If not, see
>
> #ifdef __x86_64__
>
> -/*
> - * TODO: support for 64 bits needs to be implemented.
> - */
> +#define MD_FALLBACK_FRAME_STATE_FOR x86_gnu_fallback_frame_state
> +
> +static _Unwind_Reason_Code
> +x86_gnu_fallback_frame_state
> +(struct _Unwind_Context *context, _Unwind_FrameState *fs)
> +{
> + static const unsigned char gnu_sigtramp_code[] =
> + {
> + /* rpc_wait_trampoline: */
> + 0x48, 0xc7, 0xc0, 0xe7, 0xff, 0xff, 0xff, /* mov $-25,%rax */
> + 0x0f, 0x05, /* syscall */
> + 0x49, 0x89, 0x04, 0x24, /* mov %rax,(%r12) */
> + 0x48, 0x89, 0xdc, /* mov %rbx,%rsp */
> +
> + /* trampoline: */
> + 0x5f, /* pop %rdi */
> + 0x5e, /* pop %rsi */
> + 0x5a, /* pop %rdx */
> + 0x48, 0x83, 0xc4, 0x08, /* add $0x8,%rsp */
> + 0x41, 0xff, 0xd5, /* call *%r13 */
> +
> + /* RA HERE */
> + 0x48, 0x8b, 0x7c, 0x24, 0x10, /* mov 0x10(%rsp),%rdi */
> + 0xc3, /* ret */
> +
> + /* firewall: */
> + 0xf4, /* hlt */
> + };
> +
> + const size_t gnu_sigtramp_len = sizeof gnu_sigtramp_code;
> + const size_t gnu_sigtramp_tail = 7; /* length of tail after RA */
> +
> + struct stack_contents {
> + void *sigreturn_addr;
> + void *sigreturn_returns_here;
> + struct sigcontext *return_scp;
> + } *stack_contents;
> + struct sigcontext *scp;
> + unsigned long usp;
> +
> + unsigned char *adjusted_pc = (unsigned char*)(context->ra) +
> + gnu_sigtramp_tail - gnu_sigtramp_len;
> + if (memcmp (adjusted_pc, gnu_sigtramp_code, gnu_sigtramp_len))
> + return _URC_END_OF_STACK;
> +
> + stack_contents = context->cfa;
> +
> + scp = stack_contents->return_scp;
> + usp = scp->sc_ursp;
> +
> + fs->regs.reg[0].loc.offset = (unsigned long)&scp->sc_rax - usp;
> + fs->regs.reg[1].loc.offset = (unsigned long)&scp->sc_rdx - usp;
> + fs->regs.reg[2].loc.offset = (unsigned long)&scp->sc_rcx - usp;
> + fs->regs.reg[3].loc.offset = (unsigned long)&scp->sc_rbx - usp;
> + fs->regs.reg[4].loc.offset = (unsigned long)&scp->sc_rsi - usp;
> + fs->regs.reg[5].loc.offset = (unsigned long)&scp->sc_rdi - usp;
> + fs->regs.reg[6].loc.offset = (unsigned long)&scp->sc_rbp - usp;
> + fs->regs.reg[8].loc.offset = (unsigned long)&scp->sc_r8 - usp;
> + fs->regs.reg[9].loc.offset = (unsigned long)&scp->sc_r9 - usp;
> + fs->regs.reg[10].loc.offset = (unsigned long)&scp->sc_r10 - usp;
> + fs->regs.reg[11].loc.offset = (unsigned long)&scp->sc_r11 - usp;
> + fs->regs.reg[12].loc.offset = (unsigned long)&scp->sc_r12 - usp;
> + fs->regs.reg[13].loc.offset = (unsigned long)&scp->sc_r13 - usp;
> + fs->regs.reg[14].loc.offset = (unsigned long)&scp->sc_r14 - usp;
> + fs->regs.reg[15].loc.offset = (unsigned long)&scp->sc_r15 - usp;
> + fs->regs.reg[16].loc.offset = (unsigned long)&scp->sc_rip - usp;
> +
> + /* Register 7 is rsp */
> + fs->regs.cfa_how = CFA_REG_OFFSET;
> + fs->regs.cfa_reg = 7;
> + fs->regs.cfa_offset = usp - (unsigned long) context->cfa;
> +
> + fs->regs.how[0] = REG_SAVED_OFFSET;
> + fs->regs.how[1] = REG_SAVED_OFFSET;
> + fs->regs.how[2] = REG_SAVED_OFFSET;
> + fs->regs.how[3] = REG_SAVED_OFFSET;
> + fs->regs.how[4] = REG_SAVED_OFFSET;
> + fs->regs.how[5] = REG_SAVED_OFFSET;
> + fs->regs.how[6] = REG_SAVED_OFFSET;
> + fs->regs.how[8] = REG_SAVED_OFFSET;
> + fs->regs.how[9] = REG_SAVED_OFFSET;
> + fs->regs.how[10] = REG_SAVED_OFFSET;
> + fs->regs.how[11] = REG_SAVED_OFFSET;
> + fs->regs.how[12] = REG_SAVED_OFFSET;
> + fs->regs.how[13] = REG_SAVED_OFFSET;
> + fs->regs.how[14] = REG_SAVED_OFFSET;
> + fs->regs.how[15] = REG_SAVED_OFFSET;
> + fs->regs.how[16] = REG_SAVED_OFFSET;
> +
> + fs->retaddr_column = 16;
> + fs->signal_frame = 1;
> +
> + return _URC_NO_REASON;
> +}
>
> #else /* ifdef __x86_64__ */
>
> --
> 2.43.0
>
>
--
Samuel
---
Pour une évaluation indépendante, transparente et rigoureuse !
Je soutiens la Commission d'Évaluation de l'Inria.
