/*
 * ARM64 signal handling routines
 *
 * Copyright 2010-2013 André Hentschel
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
 */

#ifdef __aarch64__

#include <assert.h>
#include <signal.h>
#include <stdlib.h>
#include <stdarg.h>
#include <stdio.h>
#include <setjmp.h>

#include "ntstatus.h"
#define WIN32_NO_STATUS
#include "windef.h"
#include "winternl.h"
#include "wine/exception.h"
#include "ntdll_misc.h"
#include "wine/debug.h"
#include "ntsyscalls.h"

WINE_DEFAULT_DEBUG_CHANNEL(seh);
WINE_DECLARE_DEBUG_CHANNEL(relay);


/*******************************************************************
 *         syscalls
 */
#define SYSCALL_ENTRY(id,name,args) __ASM_SYSCALL_FUNC( id, name )
ALL_SYSCALLS64
#undef SYSCALL_ENTRY


/**************************************************************************
 *		__chkstk (NTDLL.@)
 *
 * Supposed to touch all the stack pages, but we shouldn't need that.
 */
__ASM_GLOBAL_FUNC( __chkstk, "ret")


/***********************************************************************
 *		RtlCaptureContext (NTDLL.@)
 */
__ASM_GLOBAL_FUNC( RtlCaptureContext,
                    "str xzr, [x0, #0x8]\n\t"        /* context->X0 */
                    "stp x1, x2, [x0, #0x10]\n\t"    /* context->X1,X2 */
                    "stp x3, x4, [x0, #0x20]\n\t"    /* context->X3,X4 */
                    "stp x5, x6, [x0, #0x30]\n\t"    /* context->X5,X6 */
                    "stp x7, x8, [x0, #0x40]\n\t"    /* context->X7,X8 */
                    "stp x9, x10, [x0, #0x50]\n\t"   /* context->X9,X10 */
                    "stp x11, x12, [x0, #0x60]\n\t"  /* context->X11,X12 */
                    "stp x13, x14, [x0, #0x70]\n\t"  /* context->X13,X14 */
                    "stp x15, x16, [x0, #0x80]\n\t"  /* context->X15,X16 */
                    "stp x17, x18, [x0, #0x90]\n\t"  /* context->X17,X18 */
                    "stp x19, x20, [x0, #0xa0]\n\t"  /* context->X19,X20 */
                    "stp x21, x22, [x0, #0xb0]\n\t"  /* context->X21,X22 */
                    "stp x23, x24, [x0, #0xc0]\n\t"  /* context->X23,X24 */
                    "stp x25, x26, [x0, #0xd0]\n\t"  /* context->X25,X26 */
                    "stp x27, x28, [x0, #0xe0]\n\t"  /* context->X27,X28 */
                    "stp x29, xzr, [x0, #0xf0]\n\t"  /* context->Fp,Lr */
                    "mov x1, sp\n\t"
                    "stp x1, x30, [x0, #0x100]\n\t"  /* context->Sp,Pc */
                    "stp q0,  q1,  [x0, #0x110]\n\t" /* context->V[0-1] */
                    "stp q2,  q3,  [x0, #0x130]\n\t" /* context->V[2-3] */
                    "stp q4,  q5,  [x0, #0x150]\n\t" /* context->V[4-5] */
                    "stp q6,  q7,  [x0, #0x170]\n\t" /* context->V[6-7] */
                    "stp q8,  q9,  [x0, #0x190]\n\t" /* context->V[8-9] */
                    "stp q10, q11, [x0, #0x1b0]\n\t" /* context->V[10-11] */
                    "stp q12, q13, [x0, #0x1d0]\n\t" /* context->V[12-13] */
                    "stp q14, q15, [x0, #0x1f0]\n\t" /* context->V[14-15] */
                    "stp q16, q17, [x0, #0x210]\n\t" /* context->V[16-17] */
                    "stp q18, q19, [x0, #0x230]\n\t" /* context->V[18-19] */
                    "stp q20, q21, [x0, #0x250]\n\t" /* context->V[20-21] */
                    "stp q22, q23, [x0, #0x270]\n\t" /* context->V[22-23] */
                    "stp q24, q25, [x0, #0x290]\n\t" /* context->V[24-25] */
                    "stp q26, q27, [x0, #0x2b0]\n\t" /* context->V[26-27] */
                    "stp q28, q29, [x0, #0x2d0]\n\t" /* context->V[28-29] */
                    "stp q30, q31, [x0, #0x2f0]\n\t" /* context->V[30-31] */
                    "mov w1, #0x400000\n\t"          /* CONTEXT_ARM64 */
                    "movk w1, #0x7\n\t"              /* CONTEXT_FULL */
                    "str w1, [x0]\n\t"               /* context->ContextFlags */
                    "mrs x1, NZCV\n\t"
                    "str w1, [x0, #0x4]\n\t"         /* context->Cpsr */
                    "mrs x1, FPCR\n\t"
                    "str w1, [x0, #0x310]\n\t"       /* context->Fpcr */
                    "mrs x1, FPSR\n\t"
                    "str w1, [x0, #0x314]\n\t"       /* context->Fpsr */
                    "ret" )


/**********************************************************************
 *           virtual_unwind
 */
static NTSTATUS virtual_unwind( ULONG type, DISPATCHER_CONTEXT *dispatch, CONTEXT *context )
{
    DISPATCHER_CONTEXT_NONVOLREG_ARM64 *nonvol_regs;
    DWORD64 pc = context->Pc;
    int i;

    dispatch->ScopeIndex = 0;
    dispatch->ControlPc  = pc;
    dispatch->ControlPcIsUnwound = (context->ContextFlags & CONTEXT_UNWOUND_TO_CALL) != 0;
    if (dispatch->ControlPcIsUnwound) pc -= 4;

    nonvol_regs = (DISPATCHER_CONTEXT_NONVOLREG_ARM64 *)dispatch->NonVolatileRegisters;
    memcpy( nonvol_regs->GpNvRegs, &context->X19, sizeof(nonvol_regs->GpNvRegs) );
    for (i = 0; i < 8; i++) nonvol_regs->FpNvRegs[i] = context->V[i + 8].D[0];

    dispatch->FunctionEntry = RtlLookupFunctionEntry( pc, &dispatch->ImageBase, dispatch->HistoryTable );

    if (RtlVirtualUnwind2( type, dispatch->ImageBase, pc, dispatch->FunctionEntry, context,
                           NULL, &dispatch->HandlerData, &dispatch->EstablisherFrame,
                           NULL, NULL, NULL, &dispatch->LanguageHandler, 0 ))
    {
        WARN( "exception data not found for pc %p, lr %p\n", (void *)pc, (void *)context->Lr );
        return STATUS_INVALID_DISPOSITION;
    }
    return STATUS_SUCCESS;
}


/**********************************************************************
 *           unwind_exception_handler
 *
 * Handler for exceptions happening while calling an unwind handler.
 */
EXCEPTION_DISPOSITION WINAPI unwind_exception_handler( EXCEPTION_RECORD *record, void *frame,
                                                       CONTEXT *context, DISPATCHER_CONTEXT *dispatch )
{
    DISPATCHER_CONTEXT *orig_dispatch = ((DISPATCHER_CONTEXT **)frame)[-2];

    /* copy the original dispatcher into the current one, except for the TargetPc */
    dispatch->ControlPc          = orig_dispatch->ControlPc;
    dispatch->ImageBase          = orig_dispatch->ImageBase;
    dispatch->FunctionEntry      = orig_dispatch->FunctionEntry;
    dispatch->EstablisherFrame   = orig_dispatch->EstablisherFrame;
    dispatch->LanguageHandler    = orig_dispatch->LanguageHandler;
    dispatch->HandlerData        = orig_dispatch->HandlerData;
    dispatch->HistoryTable       = orig_dispatch->HistoryTable;
    dispatch->ScopeIndex         = orig_dispatch->ScopeIndex;
    dispatch->ControlPcIsUnwound = orig_dispatch->ControlPcIsUnwound;
    *dispatch->ContextRecord     = *orig_dispatch->ContextRecord;
    memcpy( dispatch->NonVolatileRegisters, orig_dispatch->NonVolatileRegisters,
            sizeof(DISPATCHER_CONTEXT_NONVOLREG_ARM64) );
    TRACE( "detected collided unwind\n" );
    return ExceptionCollidedUnwind;
}


/**********************************************************************
 *           call_unwind_handler
 */
DWORD WINAPI call_unwind_handler( EXCEPTION_RECORD *rec, ULONG_PTR frame,
                                  CONTEXT *context, void *dispatch, PEXCEPTION_ROUTINE handler );
__ASM_GLOBAL_FUNC( call_unwind_handler,
                   "stp x29, x30, [sp, #-32]!\n\t"
                   ".seh_save_fplr_x 32\n\t"
                   ".seh_endprologue\n\t"
                   ".seh_handler unwind_exception_handler, @except\n\t"
                   "str x3, [sp, #16]\n\t"    /* frame[-2] = dispatch */
                   "blr x4\n\t"
                   "ldp x29, x30, [sp], #32\n\t"
                   "ret" )


/***********************************************************************
 *		call_seh_handler
 */
DWORD WINAPI call_seh_handler( EXCEPTION_RECORD *rec, ULONG_PTR frame,
                               CONTEXT *context, void *dispatch, PEXCEPTION_ROUTINE handler );
__ASM_GLOBAL_FUNC( call_seh_handler,
                   "stp x29, x30, [sp, #-16]!\n\t"
                   ".seh_save_fplr_x 16\n\t"
                   ".seh_endprologue\n\t"
                   ".seh_handler nested_exception_handler, @except\n\t"
                   "blr x4\n\t"
                   "ldp x29, x30, [sp], #16\n\t"
                   "ret" )


/**********************************************************************
 *           call_seh_handlers
 *
 * Call the SEH handlers.
 */
NTSTATUS call_seh_handlers( EXCEPTION_RECORD *rec, CONTEXT *orig_context )
{
    EXCEPTION_REGISTRATION_RECORD *teb_frame = NtCurrentTeb()->Tib.ExceptionList;
    DISPATCHER_CONTEXT_NONVOLREG_ARM64 nonvol_regs;
    UNWIND_HISTORY_TABLE table;
    DISPATCHER_CONTEXT dispatch;
    CONTEXT context;
    NTSTATUS status;
    ULONG_PTR frame;
    DWORD res;

    context = *orig_context;
    dispatch.TargetPc      = 0;
    dispatch.ContextRecord = &context;
    dispatch.HistoryTable  = &table;
    dispatch.NonVolatileRegisters = nonvol_regs.Buffer;

    for (;;)
    {
        status = virtual_unwind( UNW_FLAG_EHANDLER, &dispatch, &context );
        if (status != STATUS_SUCCESS) return status;

    unwind_done:
        if (!dispatch.EstablisherFrame) break;

        if (!is_valid_frame( dispatch.EstablisherFrame ))
        {
            ERR( "invalid frame %I64x (%p-%p)\n", dispatch.EstablisherFrame,
                 NtCurrentTeb()->Tib.StackLimit, NtCurrentTeb()->Tib.StackBase );
            rec->ExceptionFlags |= EXCEPTION_STACK_INVALID;
            break;
        }

        if (dispatch.LanguageHandler)
        {
            TRACE( "calling handler %p (rec=%p, frame=%I64x context=%p, dispatch=%p)\n",
                   dispatch.LanguageHandler, rec, dispatch.EstablisherFrame, orig_context, &dispatch );
            res = call_seh_handler( rec, dispatch.EstablisherFrame, orig_context,
                                    &dispatch, dispatch.LanguageHandler );
            rec->ExceptionFlags &= EXCEPTION_NONCONTINUABLE;
            TRACE( "handler at %p returned %lu\n", dispatch.LanguageHandler, res );

            switch (res)
            {
            case ExceptionContinueExecution:
                if (rec->ExceptionFlags & EXCEPTION_NONCONTINUABLE) return STATUS_NONCONTINUABLE_EXCEPTION;
                return STATUS_SUCCESS;
            case ExceptionContinueSearch:
                break;
            case ExceptionNestedException:
                rec->ExceptionFlags |= EXCEPTION_NESTED_CALL;
                TRACE( "nested exception\n" );
                break;
            case ExceptionCollidedUnwind:
                RtlVirtualUnwind( UNW_FLAG_NHANDLER, dispatch.ImageBase,
                                  dispatch.ControlPc, dispatch.FunctionEntry,
                                  &context, &dispatch.HandlerData, &frame, NULL );
                goto unwind_done;
            default:
                return STATUS_INVALID_DISPOSITION;
            }
        }
        /* hack: call wine handlers registered in the tib list */
        else while (is_valid_frame( (ULONG_PTR)teb_frame ) && (ULONG64)teb_frame < context.Sp)
        {
            TRACE( "calling TEB handler %p (rec=%p frame=%p context=%p dispatch=%p) sp=%I64x\n",
                   teb_frame->Handler, rec, teb_frame, orig_context, &dispatch, context.Sp );
            res = call_seh_handler( rec, (ULONG_PTR)teb_frame, orig_context,
                                    &dispatch, (PEXCEPTION_ROUTINE)teb_frame->Handler );
            TRACE( "TEB handler at %p returned %lu\n", teb_frame->Handler, res );

            switch (res)
            {
            case ExceptionContinueExecution:
                if (rec->ExceptionFlags & EXCEPTION_NONCONTINUABLE) return STATUS_NONCONTINUABLE_EXCEPTION;
                return STATUS_SUCCESS;
            case ExceptionContinueSearch:
                break;
            case ExceptionNestedException:
                rec->ExceptionFlags |= EXCEPTION_NESTED_CALL;
                TRACE( "nested exception\n" );
                break;
            case ExceptionCollidedUnwind:
                RtlVirtualUnwind( UNW_FLAG_NHANDLER, dispatch.ImageBase,
                                  dispatch.ControlPc, dispatch.FunctionEntry,
                                  &context, &dispatch.HandlerData, &frame, NULL );
                teb_frame = teb_frame->Prev;
                goto unwind_done;
            default:
                return STATUS_INVALID_DISPOSITION;
            }
            teb_frame = teb_frame->Prev;
        }

        if (context.Sp == (ULONG64)NtCurrentTeb()->Tib.StackBase) break;
    }
    return STATUS_UNHANDLED_EXCEPTION;
}


/*******************************************************************
 *		KiUserExceptionDispatcher (NTDLL.@)
 */
__ASM_GLOBAL_FUNC( KiUserExceptionDispatcher,
                   ".seh_context\n\t"
                   ".seh_endprologue\n\t"
                   "adr x16, " __ASM_NAME("pWow64PrepareForException") "\n\t"
                   "ldr x16, [x16]\n\t"
                   "cbz x16, 1f\n\t"
                   "add x0, sp, #0x390\n\t"     /* rec (context + 1) */
                   "mov x1, sp\n\t"             /* context */
                   "blr x16\n"
                   "1:\tadd x0, sp, #0x390\n\t" /* rec (context + 1) */
                   "mov x1, sp\n\t"             /* context */
                   "bl " __ASM_NAME("dispatch_exception") "\n\t"
                   "brk #1" )


/*******************************************************************
 *		KiUserApcDispatcher (NTDLL.@)
 */
__ASM_GLOBAL_FUNC( KiUserApcDispatcher,
                   ".seh_context\n\t"
                   "nop\n\t"
                   ".seh_stackalloc 0x30\n\t"
                   ".seh_endprologue\n\t"
                   "ldp x16, x0, [sp]\n\t"        /* func, arg1 */
                   "ldp x1, x2, [sp, #0x10]\n\t"  /* arg2, arg3 */
                   "add x3, sp, #0x30\n\t"        /* context (FIXME) */
                   "blr x16\n\t"
                   "add x0, sp, #0x30\n\t"        /* context */
                   "ldr w1, [sp, #0x20]\n\t"      /* alertable */
                   "bl " __ASM_NAME("NtContinue") "\n\t"
                   "brk #1" )


/*******************************************************************
 *		KiUserCallbackDispatcher (NTDLL.@)
 */
__ASM_GLOBAL_FUNC( KiUserCallbackDispatcher,
                   ".seh_pushframe\n\t"
                   "nop\n\t"
                   ".seh_stackalloc 0x20\n\t"
                   "nop\n\t"
                   ".seh_save_reg lr, 0x18\n\t"
                   ".seh_endprologue\n\t"
                   ".seh_handler " __ASM_NAME("user_callback_handler") ", @except\n\t"
                   "ldr x0, [sp]\n\t"             /* args */
                   "ldp w1, w2, [sp, #0x08]\n\t"  /* len, id */
                   "ldr x3, [x18, 0x60]\n\t"      /* peb */
                   "ldr x3, [x3, 0x58]\n\t"       /* peb->KernelCallbackTable */
                   "ldr x15, [x3, x2, lsl #3]\n\t"
                   "blr x15\n\t"
                   ".globl " __ASM_NAME("KiUserCallbackDispatcherReturn") "\n"
                   __ASM_NAME("KiUserCallbackDispatcherReturn") ":\n\t"
                   "mov x2, x0\n\t"               /* status */
                   "mov x1, #0\n\t"               /* ret_len */
                   "mov x0, x1\n\t"               /* ret_ptr */
                   "bl " __ASM_NAME("NtCallbackReturn") "\n\t"
                   "bl " __ASM_NAME("RtlRaiseStatus") "\n\t"
                   "brk #1" )


/**********************************************************************
 *           consolidate_callback
 *
 * Wrapper function to call a consolidate callback from a fake frame.
 * If the callback executes RtlUnwindEx (like for example done in C++ handlers),
 * we have to skip all frames which were already processed. To do that we
 * trick the unwinding functions into thinking the call came from somewhere
 * else.
 */
void WINAPI DECLSPEC_NORETURN consolidate_callback( CONTEXT *context,
                                                    void *(CALLBACK *callback)(EXCEPTION_RECORD *),
                                                    EXCEPTION_RECORD *rec );
__ASM_GLOBAL_FUNC( consolidate_callback,
                   "stp x29, x30, [sp, #-16]!\n\t"
                   ".seh_save_fplr_x 16\n\t"
                   "sub sp, sp, #0x390\n\t"
                   ".seh_stackalloc 0x390\n\t"
                   ".seh_endprologue\n\t"
                   "mov x4, sp\n\t"
                   /* copy the context onto the stack */
                   "mov x5, #0x390/16\n"
                   "1:\tldp x6, x7, [x0], #16\n\t"
                   "stp x6, x7, [x4], #16\n\t"
                   "subs x5, x5, #1\n\t"
                   "b.ne 1b\n\t"
                   "mov x0, x2\n\t"
                   "b invoke_callback" )
__ASM_GLOBAL_FUNC( invoke_callback,
                   ".seh_context\n\t"
                   ".seh_endprologue\n\t"
                   "blr x1\n\t"
                   "str x0, [sp, #0x108]\n\t" /* context->Pc */
                   "mov x0, sp\n\t"
                   "mov w1, #0\n\t"
                   "b NtContinue" )


/*******************************************************************
 *              RtlRestoreContext (NTDLL.@)
 */
void CDECL RtlRestoreContext( CONTEXT *context, EXCEPTION_RECORD *rec )
{
    EXCEPTION_REGISTRATION_RECORD *teb_frame = NtCurrentTeb()->Tib.ExceptionList;

    if (rec && rec->ExceptionCode == STATUS_LONGJUMP && rec->NumberParameters >= 1)
    {
        struct _JUMP_BUFFER *jmp = (struct _JUMP_BUFFER *)rec->ExceptionInformation[0];
        int i;

        context->X19  = jmp->X19;
        context->X20  = jmp->X20;
        context->X21  = jmp->X21;
        context->X22  = jmp->X22;
        context->X23  = jmp->X23;
        context->X24  = jmp->X24;
        context->X25  = jmp->X25;
        context->X26  = jmp->X26;
        context->X27  = jmp->X27;
        context->X28  = jmp->X28;
        context->Fp   = jmp->Fp;
        context->Pc   = jmp->Lr;
        context->Sp   = jmp->Sp;
        context->Fpcr = jmp->Fpcr;
        context->Fpsr = jmp->Fpsr;

        for (i = 0; i < 8; i++)
            context->V[8+i].D[0] = jmp->D[i];
    }
    else if (rec && rec->ExceptionCode == STATUS_UNWIND_CONSOLIDATE && rec->NumberParameters >= 1)
    {
        PVOID (CALLBACK *consolidate)(EXCEPTION_RECORD *) = (void *)rec->ExceptionInformation[0];
        TRACE( "calling consolidate callback %p (rec=%p)\n", consolidate, rec );
        consolidate_callback( context, consolidate, rec );
    }

    /* hack: remove no longer accessible TEB frames */
    while (is_valid_frame( (ULONG_PTR)teb_frame ) && (ULONG64)teb_frame < context->Sp)
    {
        TRACE( "removing TEB frame: %p\n", teb_frame );
        teb_frame = __wine_pop_frame( teb_frame );
    }

    TRACE( "returning to %I64x stack %I64x\n", context->Pc, context->Sp );
    NtContinue( context, FALSE );
}

/*******************************************************************
 *		RtlUnwindEx (NTDLL.@)
 */
void WINAPI RtlUnwindEx( PVOID end_frame, PVOID target_ip, EXCEPTION_RECORD *rec,
                         PVOID retval, CONTEXT *context, UNWIND_HISTORY_TABLE *table )
{
    EXCEPTION_REGISTRATION_RECORD *teb_frame = NtCurrentTeb()->Tib.ExceptionList;
    DISPATCHER_CONTEXT_NONVOLREG_ARM64 nonvol_regs;
    EXCEPTION_RECORD record;
    DISPATCHER_CONTEXT dispatch;
    CONTEXT new_context;
    NTSTATUS status;
    ULONG_PTR frame;
    DWORD i, res;

    RtlCaptureContext( context );
    new_context = *context;

    /* build an exception record, if we do not have one */
    if (!rec)
    {
        record.ExceptionCode    = STATUS_UNWIND;
        record.ExceptionFlags   = 0;
        record.ExceptionRecord  = NULL;
        record.ExceptionAddress = (void *)context->Pc;
        record.NumberParameters = 0;
        rec = &record;
    }

    rec->ExceptionFlags |= EXCEPTION_UNWINDING | (end_frame ? 0 : EXCEPTION_EXIT_UNWIND);

    TRACE( "code=%lx flags=%lx end_frame=%p target_ip=%p\n",
           rec->ExceptionCode, rec->ExceptionFlags, end_frame, target_ip );
    for (i = 0; i < min( EXCEPTION_MAXIMUM_PARAMETERS, rec->NumberParameters ); i++)
        TRACE( " info[%ld]=%016I64x\n", i, rec->ExceptionInformation[i] );
    TRACE_CONTEXT( context );

    dispatch.TargetPc         = (ULONG64)target_ip;
    dispatch.ContextRecord    = context;
    dispatch.HistoryTable     = table;
    dispatch.NonVolatileRegisters = nonvol_regs.Buffer;

    for (;;)
    {
        status = virtual_unwind( UNW_FLAG_UHANDLER, &dispatch, &new_context );
        if (status != STATUS_SUCCESS) raise_status( status, rec );

    unwind_done:
        if (!dispatch.EstablisherFrame) break;

        if (!is_valid_frame( dispatch.EstablisherFrame ))
        {
            ERR( "invalid frame %I64x (%p-%p)\n", dispatch.EstablisherFrame,
                 NtCurrentTeb()->Tib.StackLimit, NtCurrentTeb()->Tib.StackBase );
            rec->ExceptionFlags |= EXCEPTION_STACK_INVALID;
            break;
        }

        if (dispatch.LanguageHandler)
        {
            if (end_frame && (dispatch.EstablisherFrame > (ULONG64)end_frame))
            {
                ERR( "invalid end frame %I64x/%p\n", dispatch.EstablisherFrame, end_frame );
                raise_status( STATUS_INVALID_UNWIND_TARGET, rec );
            }
            if (dispatch.EstablisherFrame == (ULONG64)end_frame) rec->ExceptionFlags |= EXCEPTION_TARGET_UNWIND;

            TRACE( "calling handler %p (rec=%p, frame=%I64x context=%p, dispatch=%p)\n",
                   dispatch.LanguageHandler, rec, dispatch.EstablisherFrame,
                   dispatch.ContextRecord, &dispatch );
            res = call_unwind_handler( rec, dispatch.EstablisherFrame, dispatch.ContextRecord,
                                       &dispatch, dispatch.LanguageHandler );
            TRACE( "handler %p returned %lx\n", dispatch.LanguageHandler, res );

            switch (res)
            {
            case ExceptionContinueSearch:
                rec->ExceptionFlags &= ~EXCEPTION_COLLIDED_UNWIND;
                break;
            case ExceptionCollidedUnwind:
                new_context = *context;
                RtlVirtualUnwind( UNW_FLAG_NHANDLER, dispatch.ImageBase,
                                  dispatch.ControlPc, dispatch.FunctionEntry,
                                  &new_context, &dispatch.HandlerData, &frame,
                                  NULL );
                rec->ExceptionFlags |= EXCEPTION_COLLIDED_UNWIND;
                goto unwind_done;
            default:
                raise_status( STATUS_INVALID_DISPOSITION, rec );
                break;
            }
        }
        else  /* hack: call builtin handlers registered in the tib list */
        {
            while (is_valid_frame( (ULONG_PTR)teb_frame ) &&
                   (ULONG64)teb_frame < new_context.Sp &&
                   (ULONG64)teb_frame < (ULONG64)end_frame)
            {
                TRACE( "calling TEB handler %p (rec=%p, frame=%p context=%p, dispatch=%p)\n",
                       teb_frame->Handler, rec, teb_frame, dispatch.ContextRecord, &dispatch );
                res = call_unwind_handler( rec, (ULONG_PTR)teb_frame, dispatch.ContextRecord, &dispatch,
                                           (PEXCEPTION_ROUTINE)teb_frame->Handler );
                TRACE( "handler at %p returned %lu\n", teb_frame->Handler, res );
                teb_frame = __wine_pop_frame( teb_frame );

                switch (res)
                {
                case ExceptionContinueSearch:
                    rec->ExceptionFlags &= ~EXCEPTION_COLLIDED_UNWIND;
                    break;
                case ExceptionCollidedUnwind:
                    new_context = *context;
                    RtlVirtualUnwind( UNW_FLAG_NHANDLER, dispatch.ImageBase,
                                      dispatch.ControlPc, dispatch.FunctionEntry,
                                      &new_context, &dispatch.HandlerData,
                                      &frame, NULL );
                    rec->ExceptionFlags |= EXCEPTION_COLLIDED_UNWIND;
                    goto unwind_done;
                default:
                    raise_status( STATUS_INVALID_DISPOSITION, rec );
                    break;
                }
            }
            if ((ULONG64)teb_frame == (ULONG64)end_frame && (ULONG64)end_frame < new_context.Sp) break;
        }

        if (dispatch.EstablisherFrame == (ULONG64)end_frame) break;
        *context = new_context;
    }

    if (rec->ExceptionCode != STATUS_UNWIND_CONSOLIDATE)
        context->Pc = (ULONG64)target_ip;
    else if (rec->ExceptionInformation[10] == -1)
        rec->ExceptionInformation[10] = (ULONG_PTR)&nonvol_regs;

    context->X0 = (ULONG64)retval;
    RtlRestoreContext(context, rec);
}


/*************************************************************************
 *		RtlWalkFrameChain (NTDLL.@)
 */
ULONG WINAPI RtlWalkFrameChain( void **buffer, ULONG count, ULONG flags )
{
    UNWIND_HISTORY_TABLE table;
    RUNTIME_FUNCTION *func;
    PEXCEPTION_ROUTINE handler;
    ULONG_PTR pc, frame, base;
    CONTEXT context;
    void *data;
    ULONG i, skip = flags >> 8, num_entries = 0;

    RtlCaptureContext( &context );

    for (i = 0; i < count; i++)
    {
        pc = context.Pc;
        if (context.ContextFlags & CONTEXT_UNWOUND_TO_CALL) pc -= 4;
        func = RtlLookupFunctionEntry( pc, &base, &table );
        if (RtlVirtualUnwind2( UNW_FLAG_NHANDLER, base, pc, func, &context, NULL,
                               &data, &frame, NULL, NULL, NULL, &handler, 0 ))
            break;
        if (!context.Pc) break;
        if (!frame || !is_valid_frame( frame )) break;
        if (context.Sp == (ULONG_PTR)NtCurrentTeb()->Tib.StackBase) break;
        if (i >= skip) buffer[num_entries++] = (void *)context.Pc;
    }
    return num_entries;
}


/***********************************************************************
 *		__C_ExecuteExceptionFilter
 */
__ASM_GLOBAL_FUNC( __C_ExecuteExceptionFilter,
                   "stp x29, x30, [sp, #-96]!\n\t"
                   ".seh_save_fplr_x 96\n\t"
                   "stp x19, x20, [sp, #16]\n\t"
                   ".seh_save_regp x19, 16\n\t"
                   "stp x21, x22, [sp, #32]\n\t"
                   ".seh_save_regp x21, 32\n\t"
                   "stp x23, x24, [sp, #48]\n\t"
                   ".seh_save_regp x23, 48\n\t"
                   "stp x25, x26, [sp, #64]\n\t"
                   ".seh_save_regp x25, 64\n\t"
                   "stp x27, x28, [sp, #80]\n\t"
                   ".seh_save_regp x27, 80\n\t"
                   ".seh_endprologue\n\t"
                   "ldp x19, x20, [x3, #0]\n\t" /* nonvolatile regs */
                   "ldp x21, x22, [x3, #16]\n\t"
                   "ldp x23, x24, [x3, #32]\n\t"
                   "ldp x25, x26, [x3, #48]\n\t"
                   "ldp x27, x28, [x3, #64]\n\t"
                   "ldr x1, [x3, #80]\n\t"      /* x29 = frame */
                   "blr x2\n\t"                 /* filter */
                   "ldp x19, x20, [sp, #16]\n\t"
                   "ldp x21, x22, [sp, #32]\n\t"
                   "ldp x23, x24, [sp, #48]\n\t"
                   "ldp x25, x26, [sp, #64]\n\t"
                   "ldp x27, x28, [sp, #80]\n\t"
                   "ldp x29, x30, [sp], #96\n\t"
                   "ret")


/***********************************************************************
 *		RtlRaiseException (NTDLL.@)
 */
__ASM_GLOBAL_FUNC( RtlRaiseException,
                   "sub sp, sp, #0x3b0\n\t" /* 0x390 (context) + 0x20 */
                   ".seh_stackalloc 0x3b0\n\t"
                   "stp x29, x30, [sp]\n\t"
                   ".seh_save_fplr 0\n\t"
                   ".seh_endprologue\n\t"
                   "mov x29, sp\n\t"
                   "str x0,  [sp, #0x10]\n\t"
                   "add x0,  sp, #0x20\n\t"
                   "bl " __ASM_NAME("RtlCaptureContext") "\n\t"
                   "add x1,  sp, #0x20\n\t"      /* context pointer */
                   "add x2,  sp, #0x3b0\n\t"     /* orig stack pointer */
                   "str x2,  [x1, #0x100]\n\t"   /* context->Sp */
                   "ldr x0,  [sp, #0x10]\n\t"    /* original first parameter */
                   "str x0,  [x1, #0x08]\n\t"    /* context->X0 */
                   "ldp x4, x5, [sp]\n\t"        /* frame pointer, return address */
                   "stp x4, x5, [x1, #0xf0]\n\t" /* context->Fp, Lr */
                   "str  x5, [x1, #0x108]\n\t"   /* context->Pc */
                   "str  x5, [x0, #0x10]\n\t"    /* rec->ExceptionAddress */
                   "ldr w2, [x1]\n\t"            /* context->ContextFlags */
                   "orr w2, w2, #0x20000000\n\t" /* CONTEXT_UNWOUND_TO_CALL */
                   "str w2, [x1]\n\t"
                   "ldr x3, [x18, #0x60]\n\t"    /* peb */
                   "ldrb w2, [x3, #2]\n\t"       /* peb->BeingDebugged */
                   "cbnz w2, 1f\n\t"
                   "bl " __ASM_NAME("dispatch_exception") "\n"
                   "1:\tmov  x2, #1\n\t"
                   "bl " __ASM_NAME("NtRaiseException") "\n\t"
                   "bl " __ASM_NAME("RtlRaiseStatus") /* does not return */ );


/***********************************************************************
 *           _setjmpex (NTDLL.@)
 */
__ASM_GLOBAL_FUNC( NTDLL__setjmpex,
                   ".seh_endprologue\n\t"
                   "str x1,       [x0]\n\t"        /* jmp_buf->Frame */
                   "stp x19, x20, [x0, #0x10]\n\t" /* jmp_buf->X19, X20 */
                   "stp x21, x22, [x0, #0x20]\n\t" /* jmp_buf->X21, X22 */
                   "stp x23, x24, [x0, #0x30]\n\t" /* jmp_buf->X23, X24 */
                   "stp x25, x26, [x0, #0x40]\n\t" /* jmp_buf->X25, X26 */
                   "stp x27, x28, [x0, #0x50]\n\t" /* jmp_buf->X27, X28 */
                   "stp x29, x30, [x0, #0x60]\n\t" /* jmp_buf->Fp,  Lr  */
                   "mov x2,  sp\n\t"
                   "str x2,       [x0, #0x70]\n\t" /* jmp_buf->Sp */
                   "mrs x2,  fpcr\n\t"
                   "mrs x3,  fpsr\n\t"
                   "stp w2, w3,   [x0, #0x78]\n\t" /* jmp_buf->Fpcr,Fpsr */
                   "stp d8,  d9,  [x0, #0x80]\n\t" /* jmp_buf->D[0-1] */
                   "stp d10, d11, [x0, #0x90]\n\t" /* jmp_buf->D[2-3] */
                   "stp d12, d13, [x0, #0xa0]\n\t" /* jmp_buf->D[4-5] */
                   "stp d14, d15, [x0, #0xb0]\n\t" /* jmp_buf->D[6-7] */
                   "mov x0, #0\n\t"
                   "ret" )


/*******************************************************************
 *		longjmp (NTDLL.@)
 */
void __cdecl NTDLL_longjmp( _JUMP_BUFFER *buf, int retval )
{
    EXCEPTION_RECORD rec;

    if (!retval) retval = 1;

    rec.ExceptionCode = STATUS_LONGJUMP;
    rec.ExceptionFlags = 0;
    rec.ExceptionRecord = NULL;
    rec.ExceptionAddress = NULL;
    rec.NumberParameters = 1;
    rec.ExceptionInformation[0] = (DWORD_PTR)buf;
    RtlUnwind( (void *)buf->Frame, (void *)buf->Lr, &rec, IntToPtr(retval) );
}


/***********************************************************************
 *           RtlUserThreadStart (NTDLL.@)
 */
__ASM_GLOBAL_FUNC( RtlUserThreadStart,
                   "stp x29, x30, [sp, #-16]!\n\t"
                   ".seh_save_fplr_x 16\n\t"
                   ".seh_endprologue\n\t"
                   "adr x8, " __ASM_NAME("pBaseThreadInitThunk") "\n\t"
                   "ldr x8, [x8]\n\t"
                   "mov x2, x1\n\t"
                   "mov x1, x0\n\t"
                   "mov x0, #0\n\t"
                   "blr x8\n\t"
                   ".seh_handler call_unhandled_exception_handler, @except" )

/******************************************************************
 *		LdrInitializeThunk (NTDLL.@)
 */
void WINAPI LdrInitializeThunk( CONTEXT *context, ULONG_PTR unk2, ULONG_PTR unk3, ULONG_PTR unk4 )
{
    loader_init( context, (void **)&context->X0 );
    TRACE_(relay)( "\1Starting thread proc %p (arg=%p)\n", (void *)context->X0, (void *)context->X1 );
    NtContinue( context, TRUE );
}


/***********************************************************************
 *           process_breakpoint
 */
__ASM_GLOBAL_FUNC( process_breakpoint,
                   ".seh_endprologue\n\t"
                   ".seh_handler process_breakpoint_handler, @except\n\t"
                   "brk #0xf000\n\t"
                   "ret\n"
                   "process_breakpoint_handler:\n\t"
                   "ldr x4, [x2, #0x108]\n\t" /* context->Pc */
                   "add x4, x4, #4\n\t"
                   "str x4, [x2, #0x108]\n\t"
                   "mov w0, #0\n\t"           /* ExceptionContinueExecution */
                   "ret" )

/***********************************************************************
 *		DbgUiRemoteBreakin   (NTDLL.@)
 */
__ASM_GLOBAL_FUNC( DbgUiRemoteBreakin,
                   "stp x29, x30, [sp, #-16]!\n\t"
                   ".seh_save_fplr_x 16\n\t"
                   ".seh_endprologue\n\t"
                   ".seh_handler DbgUiRemoteBreakin_handler, @except\n\t"
                   "ldr x0, [x18, #0x60]\n\t"       /* NtCurrentTeb()->Peb */
                   "ldrb w0, [x0, 0x02]\n\t"        /* peb->BeingDebugged */
                   "cbz w0, 1f\n\t"
                   "bl " __ASM_NAME("DbgBreakPoint") "\n"
                   "1:\tmov w0, #0\n\t"
                   "bl " __ASM_NAME("RtlExitUserThread") "\n"
                   "DbgUiRemoteBreakin_handler:\n\t"
                   "mov sp, x1\n\t"                 /* frame */
                   "b 1b" )

/**********************************************************************
 *              DbgBreakPoint   (NTDLL.@)
 */
__ASM_GLOBAL_FUNC( DbgBreakPoint, "brk #0xf000; ret"
                    "\n\tnop; nop; nop; nop; nop; nop; nop; nop"
                    "\n\tnop; nop; nop; nop; nop; nop" );

/**********************************************************************
 *              DbgUserBreakPoint   (NTDLL.@)
 */
__ASM_GLOBAL_FUNC( DbgUserBreakPoint, "brk #0xf000; ret"
                    "\n\tnop; nop; nop; nop; nop; nop; nop; nop"
                    "\n\tnop; nop; nop; nop; nop; nop" );

#endif  /* __aarch64__ */