This file contains the code that implements the syscall path based
on the epc instruction. The epc instruction, given the permissions of the page in which the epc is located, allows the privilege level to be increased with little or no overhead. The previous privilege level is recorded in the current frame marker and is restored by a regular (function) return. Since the epc instruction has to live in a page with non-standard properties, we hardwire a "gateway" page in the address space. The address of the gateway page is exported to userland in ar.k7. This allows us to rewire the page without breaking the ABI. The syscall stubs in libc are regular function calls that slightly differ from the normal runtime. The difference is mostly to simplify the stubs themselves by by moving some of the logic to the kernel. The libc stubs call into the gateway page (offset 0), from where the kernel trampolines to the code that sets up a minimal trapframe and arranges to execute from the kernel stack. The way back is basicly the same. The kernel returns to the gateway page, whereby privilege is dropped, and jumps back to the syscall stub. Only the special registers are saved in the trapframe. None of the scratch registers are preserved and since the kernel follows the same runtime model, none of the preserved registers are saved. Future enhancements can include the implementation of lightweight syscalls, where kernel functions are performed without setting up a trapframe. Good candidates are the *context syscalls for example. Now that there's a gateway page from which code can be executed in a non-privileged context, we also have the ideal place to put the signal trampolines. By moving the signal trampolines from the user stack to the gateway page, we open up the doors to unexecutable stacks. The gateway page contains signal trampolines for both the "legacy" break-based syscall code and the new and improved epc- based syscall code. Approved: re@ (blanket)
This commit is contained in:
Marcel Moolenaar
parent
4a0d6dfd2c
commit
1d67adffd6
Notes:
svn2git
2020-12-20 02:59:44 +00:00
svn path=/head/; revision=115017
565
sys/ia64/ia64/syscall.S
Normal file
565
sys/ia64/ia64/syscall.S
Normal file
@ -0,0 +1,565 @@
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/*
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* Copyright (c) 2002, 2003 Marcel Moolenaar
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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*
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*
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* $FreeBSD$
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*/
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#include <sys/syscall.h>
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#include <machine/asm.h>
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#include <assym.s>
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/*
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* A process performs a syscall by performing an indirect call to the
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* address stored in ar.k5. The contents of ar.pfs and rp should be
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* saved prior to the syscall in r9 and r10 respectively. The kernel
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* will restore these values on return. The value of gp is preserved
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* across the call. This allows for small enough syscall stubs without
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* getting too weird.
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* The address in ar.k5 is the start of the EPC gateway page and also
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* the syscall entry point. The syscall code in the gateway page is
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* primarily responsible for increasing the privilege level, but will
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* also make sure we have a reliable psr.
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*
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* A process defines:
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* r8 - syscall number
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* r9 - copy of ar.pfs
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* r10 - copy of rp
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* in0-in7 - syscall arguments
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*
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* A syscall returns:
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* r8+r9 - syscall return value(s)
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* r10 - syscall error flag
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* ar.pfs - restored from r9
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* rp - restored from r10
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* gp - preserved
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*
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* The EPC syscall code defines:
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* r11 - copy of psr.l
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* r14 - Kernel memory stack
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* r15 - Kernel register stack
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*
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* Also in the gateway page are the signal trampolines. As such, stacks
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* don't have to be made executable per se. Since debuggers have a need
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* to know about trampolines, we probably need to define a table of
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* vectors or something along those lines so that debuggers can get the
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* information they need and we have the freedom to move code around.
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*/
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.section .text.gateway, "ax"
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.align PAGE_SIZE
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.global ia64_gateway_page
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ia64_gateway_page:
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{ .mmb
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mov r14=ar.k7 // Memory stack
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mov r15=ar.k6 // Register stack
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epc
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;;
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}
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{ .mlx
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mov r11=psr
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movl r31=epc_syscall
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;;
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}
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{ .mib
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rum psr.be
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mov b7=r31
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br b7
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;;
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}
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gw_ret:
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{ .mmi
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mov ar.rnat=r22
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mov ar.rsc=r24
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mov ar.pfs=r28
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}
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{ .mib
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mov ar.fpsr=r25
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mov b0=r29
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br.sptk b6
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;;
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}
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gw_ret_ia32:
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mov ar.rnat=r0
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mov ar.rsc=0xc
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mov ar.pfs=r0
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;;
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br.ia.sptk b6
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;;
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ENTRY(break_sigtramp, 0)
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{ .mib
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mov ar.rsc=0
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cmp.ne p15,p0=0,gp
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cover
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;;
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}
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{ .mmi
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flushrs
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(p15) invala
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add r16=16+UC_MCONTEXT+MC_SPECIAL,sp
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;;
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}
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{ .mmi
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mov r17=ar.bsp
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mov r18=ar.rnat
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add r14=40,r16
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;;
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}
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{ .mmi
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st8 [r14]=r17,64 // bspstore
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(p15) mov ar.bspstore=gp
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add r15=48,r16
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;;
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}
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{ .mmi
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st8 [r15]=r18 // rnat
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st8 [r14]=r0 // ndirty
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nop 0
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;;
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}
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{ .mmi
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alloc r14=ar.pfs, 0, 0, 3, 0
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mov ar.rsc=15
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mov out0=r8
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;;
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}
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{ .mmi
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ld8 r16=[r10],8 // function address
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;;
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ld8 gp=[r10] // function's gp value
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mov b7=r16
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;;
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}
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{ .mib
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mov out1=r9
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add out2=16,sp
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br.call.sptk rp=b7
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;;
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}
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{ .mmi
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mov r15=SYS_sigreturn
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add out0=16,sp
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break 0x100000
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;;
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}
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{ .mmi
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mov r15=SYS_exit
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mov out0=ret0
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break 0x100000
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;;
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}
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END(break_sigtramp)
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ENTRY(epc_sigtramp, 0)
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{ .mib
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mov ar.rsc=0
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cmp.ne p15,p0=0,gp
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cover
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;;
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}
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{ .mmi
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flushrs
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(p15) invala
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add r16=16+UC_MCONTEXT+MC_SPECIAL,sp
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;;
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}
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{ .mmi
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mov r17=ar.bsp
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mov r18=ar.rnat
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add r14=32,r16
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;;
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}
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{ .mmi
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(p15) mov ar.bspstore=gp
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ld8 r19=[r14],8
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add r15=48,r16
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;;
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}
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{ .mmi
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st8 [r14]=r17,64 // bspstore
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st8 [r15]=r18,-16 // rnat
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dep r19=r19,r19,7,7
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;;
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}
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{ .mmi
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st8 [r14]=r0 // ndirty
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st8 [r15]=r19 // pfs
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nop 0
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;;
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}
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{ .mmi
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alloc r14=ar.pfs, 0, 0, 3, 0
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mov ar.rsc=15
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mov out0=r8
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;;
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}
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{ .mmi
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ld8 r16=[r10],8 // function address
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;;
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ld8 gp=[r10] // function's gp value
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mov b7=r16
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;;
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}
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{ .mib
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mov out1=r9
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add out2=16,sp
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br.call.sptk rp=b7
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;;
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}
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add out0=16,sp
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CALLSYS_NOERROR(sigreturn)
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mov out0=ret0
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CALLSYS_NOERROR(exit)
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END(epc_sigtramp)
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.align PAGE_SIZE
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.text
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ENTRY(epc_syscall, 8)
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.prologue
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.unwabi @svr4, 'E'
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.save rp, r0
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rsm psr.i
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;;
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{ .mmi
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mov r16=ar.rsc
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mov ar.rsc=0
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mov r17=r13
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;;
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}
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{ .mmi
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mov r18=ar.bspstore
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mov r19=ar.rnat
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add r30=-SIZEOF_TRAPFRAME,r14
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;;
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}
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{ .mmi
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mov ar.bspstore=r15
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mov r13=ar.k4
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dep r30=0,r30,0,10
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;;
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}
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{ .mii
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mov r20=sp
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add r31=8,r30
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add sp=-16,r30
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;;
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}
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{ .mmi
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mov r21=ar.unat
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mov r22=ar.fpsr
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sub r29=r14,r30
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;;
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}
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{ .mmi
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mov r23=ar.bsp
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mov ar.rsc=3
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add r28=FRAME_SYSCALL,r0
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;;
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}
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{ .mmi
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st8 [r30]=r29,16 // tf_length
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st8 [r31]=r28,16 // tf_flags
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mov r24=rp
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;;
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}
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{ .mmi
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st8 [r30]=r20,16 // sp
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st8 [r31]=r21,16 // unat
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mov r25=pr
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;;
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}
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{ .mmi
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st8 [r30]=r24,16 // rp (syscall stub)
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st8 [r31]=r25,16 // pr
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mov r26=ar.pfs
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;;
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}
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{ .mmi
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st8 [r30]=r26,16 // pfs (syscall stub)
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st8 [r31]=r18,16 // bspstore
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sub r27=r23,r15
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;;
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}
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{ .mmi
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st8 [r30]=r19,16 // rnat
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st8 [r31]=r0,16 // __spare
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nop 0
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;;
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}
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{ .mmi
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st8 [r30]=r17,16 // tp
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st8 [r31]=r16,16 // rsc
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dep r11=-1,r11,32,2 // Set psr.cpl=3
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;;
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}
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{ .mmi
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st8 [r30]=r22,16 // fpsr
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st8 [r31]=r11,16 // psr
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nop 0
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;;
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}
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{ .mmi
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st8 [r30]=r1,16 // gp
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st8 [r31]=r27,16 // ndirty
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nop 0
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;;
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}
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{ .mmi
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st8 [r30]=r9,16 // pfs (syscall caller)
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st8 [r31]=r10,16 // rp (syscall caller)
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nop 0
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;;
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}
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{ .mmi
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st8 [r30]=r0,80 // ifa
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st8 [r31]=r0,80 // isr
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nop 0
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;;
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}
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{ .mmi
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alloc r14=ar.pfs,0,0,8,0
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st8 [r30]=r8,16 // syscall number (=r15)
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nop 0
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;;
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}
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{ .mmi
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.mem.offset 0,0
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st8.spill [r31]=r32,16 // arg0 (=r16)
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.mem.offset 8,0
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st8.spill [r30]=r33,16 // arg1 (=r17)
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nop 0
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;;
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}
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{ .mmi
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.mem.offset 16,0
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st8.spill [r31]=r34,16 // arg2 (=r18)
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.mem.offset 24,0
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st8.spill [r30]=r35,16 // arg3 (=r19)
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nop 0
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;;
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}
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{ .mmi
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.mem.offset 32,0
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st8.spill [r31]=r36,16 // arg4 (=r20)
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.mem.offset 40,0
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st8.spill [r30]=r37,16 // arg5 (=r21)
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nop 0
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;;
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}
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{ .mmi
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.mem.offset 48,0
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st8.spill [r31]=r38 // arg6 (=r22)
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.mem.offset 56,0
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st8.spill [r30]=r39 // arg7 (=r23)
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nop 0
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;;
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}
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{ .mlx
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ssm psr.dfh|psr.ac|psr.i
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movl gp=__gp
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;;
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||||
}
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||||
epc_syscall_restart:
|
||||
{ .mib
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srlz.d
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add out0=16,sp
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br.call.sptk rp=syscall
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;;
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||||
}
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||||
{ .mfb
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add out0=16,sp
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nop 0
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||||
br.call.sptk rp=do_ast
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;;
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}
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||||
{ .mfb
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cmp4.eq p15,p0=ERESTART,r8
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nop 0
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(p15) br.spnt epc_syscall_restart
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;;
|
||||
}
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.global epc_syscall_return
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epc_syscall_return:
|
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{ .mmi
|
||||
alloc r31=ar.pfs,0,0,0,0
|
||||
add r14=32,sp
|
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add r15=16,sp
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||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
ld8 r31=[r15],24 // tf_length
|
||||
ld8 r16=[r14],16 // sp
|
||||
add sp=16,sp
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
ld8 r17=[r15],16 // unat (before)
|
||||
ld8 r18=[r14],16 // rp (syscall stub)
|
||||
add r31=r31,sp
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
ld8 r19=[r15],16 // pr
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||||
ld8 r20=[r14],16 // pfs (syscall stub)
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mov b6=r18
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||||
;;
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||||
}
|
||||
{ .mmi
|
||||
ld8 r21=[r15],24 // bspstore
|
||||
ld8 r22=[r14],24 // rnat
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||||
mov pr=r19,0x1fffe
|
||||
;;
|
||||
}
|
||||
{ .mmb
|
||||
ld8 r23=[r15],16 // tp
|
||||
ld8 r24=[r14],16 // rsc
|
||||
nop 0
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
ld8 r25=[r15],16 // fpsr
|
||||
ld8 r26=[r14],16 // psr
|
||||
mov ar.pfs=r20
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
ld8 gp=[r15],16 // gp
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||||
ld8 r27=[r14],16 // ndirty
|
||||
tbit.z p14,p15=r26,34 // p14=ia64, p15=ia32
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
ld8 r28=[r15],56 // pfs (syscall caller)
|
||||
ld8 r29=[r14],56 // rp (syscall caller)
|
||||
shl r27=r27,16
|
||||
;;
|
||||
}
|
||||
{ .mmb
|
||||
ld8 r8=[r15],16 // r8
|
||||
mov ar.rsc=r27
|
||||
nop 0
|
||||
;;
|
||||
}
|
||||
{ .mmb
|
||||
ld8 r9=[r14],40 // r9
|
||||
ld8 r10=[r15],40 // r10
|
||||
(p15) br.spnt epc_syscall_setup_ia32
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
loadrs
|
||||
mov r14=ar.k5
|
||||
mov sp=r16
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
mov r30=ar.bspstore
|
||||
;;
|
||||
mov ar.bspstore=r21
|
||||
dep r30=0,r30,0,9
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
mov ar.k6=r30
|
||||
mov ar.k7=r31
|
||||
mov r13=r23
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
mov psr.l=r26
|
||||
mov ar.unat=r17
|
||||
add r14=gw_ret-ia64_gateway_page,r14
|
||||
;;
|
||||
}
|
||||
{ .mib
|
||||
srlz.d
|
||||
mov b7=r14
|
||||
br.ret.sptk b7
|
||||
;;
|
||||
}
|
||||
epc_syscall_setup_ia32:
|
||||
{ .mmi
|
||||
loadrs
|
||||
mov ar.k7=r31
|
||||
mov sp=r16
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
mov r30=ar.bspstore
|
||||
;;
|
||||
mov ar.bspstore=r21
|
||||
dep r30=0,r30,0,9
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
mov ar.k6=r30
|
||||
mov ar.unat=r17
|
||||
mov r11=r26
|
||||
;;
|
||||
}
|
||||
|
||||
ld8 r16=[r14],16
|
||||
ld8 r17=[r15],16
|
||||
;;
|
||||
ld8 r18=[r14],16
|
||||
ld8 r19=[r15],16
|
||||
;;
|
||||
ld8 r20=[r14],16
|
||||
ld8 r21=[r15],16
|
||||
;;
|
||||
ld8 r22=[r14],16
|
||||
ld8 r23=[r15],16
|
||||
;;
|
||||
ld8 r24=[r14],16
|
||||
ld8 r25=[r15],16
|
||||
;;
|
||||
ld8 r26=[r14],16
|
||||
ld8 r27=[r15],16
|
||||
;;
|
||||
ld8 r28=[r14],16
|
||||
ld8 r29=[r15],16
|
||||
;;
|
||||
ld8 r30=[r14],40
|
||||
ld8 r31=[r15],40
|
||||
;;
|
||||
ld8 r2=[r14],16
|
||||
ld8 r3=[r15],8
|
||||
;;
|
||||
mov ar.csd=r2
|
||||
mov ar.ssd=r3
|
||||
;;
|
||||
mov r2=ar.k5
|
||||
mov psr.l=r11
|
||||
;;
|
||||
srlz.d
|
||||
add r2=gw_ret_ia32-ia64_gateway_page,r2
|
||||
;;
|
||||
mov b7=r2
|
||||
br.ret.sptk b7
|
||||
;;
|
||||
END(epc_syscall)
|
||||
565
sys/ia64/ia64/syscall.s
Normal file
565
sys/ia64/ia64/syscall.s
Normal file
@ -0,0 +1,565 @@
|
||||
/*
|
||||
* Copyright (c) 2002, 2003 Marcel Moolenaar
|
||||
* All rights reserved.
|
||||
*
|
||||
* Redistribution and use in source and binary forms, with or without
|
||||
* modification, are permitted provided that the following conditions
|
||||
* are met:
|
||||
*
|
||||
* 1. Redistributions of source code must retain the above copyright
|
||||
* notice, this list of conditions and the following disclaimer.
|
||||
* 2. Redistributions in binary form must reproduce the above copyright
|
||||
* notice, this list of conditions and the following disclaimer in the
|
||||
* documentation and/or other materials provided with the distribution.
|
||||
*
|
||||
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
|
||||
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
|
||||
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
|
||||
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
|
||||
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
|
||||
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
||||
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
||||
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
||||
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
|
||||
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
||||
*
|
||||
* $FreeBSD$
|
||||
*/
|
||||
|
||||
#include <sys/syscall.h>
|
||||
#include <machine/asm.h>
|
||||
#include <assym.s>
|
||||
|
||||
/*
|
||||
* A process performs a syscall by performing an indirect call to the
|
||||
* address stored in ar.k5. The contents of ar.pfs and rp should be
|
||||
* saved prior to the syscall in r9 and r10 respectively. The kernel
|
||||
* will restore these values on return. The value of gp is preserved
|
||||
* across the call. This allows for small enough syscall stubs without
|
||||
* getting too weird.
|
||||
* The address in ar.k5 is the start of the EPC gateway page and also
|
||||
* the syscall entry point. The syscall code in the gateway page is
|
||||
* primarily responsible for increasing the privilege level, but will
|
||||
* also make sure we have a reliable psr.
|
||||
*
|
||||
* A process defines:
|
||||
* r8 - syscall number
|
||||
* r9 - copy of ar.pfs
|
||||
* r10 - copy of rp
|
||||
* in0-in7 - syscall arguments
|
||||
*
|
||||
* A syscall returns:
|
||||
* r8+r9 - syscall return value(s)
|
||||
* r10 - syscall error flag
|
||||
* ar.pfs - restored from r9
|
||||
* rp - restored from r10
|
||||
* gp - preserved
|
||||
*
|
||||
* The EPC syscall code defines:
|
||||
* r11 - copy of psr.l
|
||||
* r14 - Kernel memory stack
|
||||
* r15 - Kernel register stack
|
||||
*
|
||||
* Also in the gateway page are the signal trampolines. As such, stacks
|
||||
* don't have to be made executable per se. Since debuggers have a need
|
||||
* to know about trampolines, we probably need to define a table of
|
||||
* vectors or something along those lines so that debuggers can get the
|
||||
* information they need and we have the freedom to move code around.
|
||||
*/
|
||||
|
||||
.section .text.gateway, "ax"
|
||||
.align PAGE_SIZE
|
||||
.global ia64_gateway_page
|
||||
ia64_gateway_page:
|
||||
{ .mmb
|
||||
mov r14=ar.k7 // Memory stack
|
||||
mov r15=ar.k6 // Register stack
|
||||
epc
|
||||
;;
|
||||
}
|
||||
{ .mlx
|
||||
mov r11=psr
|
||||
movl r31=epc_syscall
|
||||
;;
|
||||
}
|
||||
{ .mib
|
||||
rum psr.be
|
||||
mov b7=r31
|
||||
br b7
|
||||
;;
|
||||
}
|
||||
gw_ret:
|
||||
{ .mmi
|
||||
mov ar.rnat=r22
|
||||
mov ar.rsc=r24
|
||||
mov ar.pfs=r28
|
||||
}
|
||||
{ .mib
|
||||
mov ar.fpsr=r25
|
||||
mov b0=r29
|
||||
br.sptk b6
|
||||
;;
|
||||
}
|
||||
gw_ret_ia32:
|
||||
mov ar.rnat=r0
|
||||
mov ar.rsc=0xc
|
||||
mov ar.pfs=r0
|
||||
;;
|
||||
br.ia.sptk b6
|
||||
;;
|
||||
|
||||
ENTRY(break_sigtramp, 0)
|
||||
{ .mib
|
||||
mov ar.rsc=0
|
||||
cmp.ne p15,p0=0,gp
|
||||
cover
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
flushrs
|
||||
(p15) invala
|
||||
add r16=16+UC_MCONTEXT+MC_SPECIAL,sp
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
mov r17=ar.bsp
|
||||
mov r18=ar.rnat
|
||||
add r14=40,r16
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
st8 [r14]=r17,64 // bspstore
|
||||
(p15) mov ar.bspstore=gp
|
||||
add r15=48,r16
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
st8 [r15]=r18 // rnat
|
||||
st8 [r14]=r0 // ndirty
|
||||
nop 0
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
alloc r14=ar.pfs, 0, 0, 3, 0
|
||||
mov ar.rsc=15
|
||||
mov out0=r8
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
ld8 r16=[r10],8 // function address
|
||||
;;
|
||||
ld8 gp=[r10] // function's gp value
|
||||
mov b7=r16
|
||||
;;
|
||||
}
|
||||
{ .mib
|
||||
mov out1=r9
|
||||
add out2=16,sp
|
||||
br.call.sptk rp=b7
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
mov r15=SYS_sigreturn
|
||||
add out0=16,sp
|
||||
break 0x100000
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
mov r15=SYS_exit
|
||||
mov out0=ret0
|
||||
break 0x100000
|
||||
;;
|
||||
}
|
||||
END(break_sigtramp)
|
||||
|
||||
ENTRY(epc_sigtramp, 0)
|
||||
{ .mib
|
||||
mov ar.rsc=0
|
||||
cmp.ne p15,p0=0,gp
|
||||
cover
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
flushrs
|
||||
(p15) invala
|
||||
add r16=16+UC_MCONTEXT+MC_SPECIAL,sp
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
mov r17=ar.bsp
|
||||
mov r18=ar.rnat
|
||||
add r14=32,r16
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
(p15) mov ar.bspstore=gp
|
||||
ld8 r19=[r14],8
|
||||
add r15=48,r16
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
st8 [r14]=r17,64 // bspstore
|
||||
st8 [r15]=r18,-16 // rnat
|
||||
dep r19=r19,r19,7,7
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
st8 [r14]=r0 // ndirty
|
||||
st8 [r15]=r19 // pfs
|
||||
nop 0
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
alloc r14=ar.pfs, 0, 0, 3, 0
|
||||
mov ar.rsc=15
|
||||
mov out0=r8
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
ld8 r16=[r10],8 // function address
|
||||
;;
|
||||
ld8 gp=[r10] // function's gp value
|
||||
mov b7=r16
|
||||
;;
|
||||
}
|
||||
{ .mib
|
||||
mov out1=r9
|
||||
add out2=16,sp
|
||||
br.call.sptk rp=b7
|
||||
;;
|
||||
}
|
||||
add out0=16,sp
|
||||
CALLSYS_NOERROR(sigreturn)
|
||||
mov out0=ret0
|
||||
CALLSYS_NOERROR(exit)
|
||||
END(epc_sigtramp)
|
||||
|
||||
.align PAGE_SIZE
|
||||
|
||||
.text
|
||||
|
||||
ENTRY(epc_syscall, 8)
|
||||
.prologue
|
||||
.unwabi @svr4, 'E'
|
||||
.save rp, r0
|
||||
|
||||
rsm psr.i
|
||||
;;
|
||||
{ .mmi
|
||||
mov r16=ar.rsc
|
||||
mov ar.rsc=0
|
||||
mov r17=r13
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
mov r18=ar.bspstore
|
||||
mov r19=ar.rnat
|
||||
add r30=-SIZEOF_TRAPFRAME,r14
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
mov ar.bspstore=r15
|
||||
mov r13=ar.k4
|
||||
dep r30=0,r30,0,10
|
||||
;;
|
||||
}
|
||||
{ .mii
|
||||
mov r20=sp
|
||||
add r31=8,r30
|
||||
add sp=-16,r30
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
mov r21=ar.unat
|
||||
mov r22=ar.fpsr
|
||||
sub r29=r14,r30
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
mov r23=ar.bsp
|
||||
mov ar.rsc=3
|
||||
add r28=FRAME_SYSCALL,r0
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
st8 [r30]=r29,16 // tf_length
|
||||
st8 [r31]=r28,16 // tf_flags
|
||||
mov r24=rp
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
st8 [r30]=r20,16 // sp
|
||||
st8 [r31]=r21,16 // unat
|
||||
mov r25=pr
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
st8 [r30]=r24,16 // rp (syscall stub)
|
||||
st8 [r31]=r25,16 // pr
|
||||
mov r26=ar.pfs
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
st8 [r30]=r26,16 // pfs (syscall stub)
|
||||
st8 [r31]=r18,16 // bspstore
|
||||
sub r27=r23,r15
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
st8 [r30]=r19,16 // rnat
|
||||
st8 [r31]=r0,16 // __spare
|
||||
nop 0
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
st8 [r30]=r17,16 // tp
|
||||
st8 [r31]=r16,16 // rsc
|
||||
dep r11=-1,r11,32,2 // Set psr.cpl=3
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
st8 [r30]=r22,16 // fpsr
|
||||
st8 [r31]=r11,16 // psr
|
||||
nop 0
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
st8 [r30]=r1,16 // gp
|
||||
st8 [r31]=r27,16 // ndirty
|
||||
nop 0
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
st8 [r30]=r9,16 // pfs (syscall caller)
|
||||
st8 [r31]=r10,16 // rp (syscall caller)
|
||||
nop 0
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
st8 [r30]=r0,80 // ifa
|
||||
st8 [r31]=r0,80 // isr
|
||||
nop 0
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
alloc r14=ar.pfs,0,0,8,0
|
||||
st8 [r30]=r8,16 // syscall number (=r15)
|
||||
nop 0
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
.mem.offset 0,0
|
||||
st8.spill [r31]=r32,16 // arg0 (=r16)
|
||||
.mem.offset 8,0
|
||||
st8.spill [r30]=r33,16 // arg1 (=r17)
|
||||
nop 0
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
.mem.offset 16,0
|
||||
st8.spill [r31]=r34,16 // arg2 (=r18)
|
||||
.mem.offset 24,0
|
||||
st8.spill [r30]=r35,16 // arg3 (=r19)
|
||||
nop 0
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
.mem.offset 32,0
|
||||
st8.spill [r31]=r36,16 // arg4 (=r20)
|
||||
.mem.offset 40,0
|
||||
st8.spill [r30]=r37,16 // arg5 (=r21)
|
||||
nop 0
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
.mem.offset 48,0
|
||||
st8.spill [r31]=r38 // arg6 (=r22)
|
||||
.mem.offset 56,0
|
||||
st8.spill [r30]=r39 // arg7 (=r23)
|
||||
nop 0
|
||||
;;
|
||||
}
|
||||
{ .mlx
|
||||
ssm psr.dfh|psr.ac|psr.i
|
||||
movl gp=__gp
|
||||
;;
|
||||
}
|
||||
epc_syscall_restart:
|
||||
{ .mib
|
||||
srlz.d
|
||||
add out0=16,sp
|
||||
br.call.sptk rp=syscall
|
||||
;;
|
||||
}
|
||||
{ .mfb
|
||||
add out0=16,sp
|
||||
nop 0
|
||||
br.call.sptk rp=do_ast
|
||||
;;
|
||||
}
|
||||
{ .mfb
|
||||
cmp4.eq p15,p0=ERESTART,r8
|
||||
nop 0
|
||||
(p15) br.spnt epc_syscall_restart
|
||||
;;
|
||||
}
|
||||
.global epc_syscall_return
|
||||
epc_syscall_return:
|
||||
{ .mmi
|
||||
alloc r31=ar.pfs,0,0,0,0
|
||||
add r14=32,sp
|
||||
add r15=16,sp
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
ld8 r31=[r15],24 // tf_length
|
||||
ld8 r16=[r14],16 // sp
|
||||
add sp=16,sp
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
ld8 r17=[r15],16 // unat (before)
|
||||
ld8 r18=[r14],16 // rp (syscall stub)
|
||||
add r31=r31,sp
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
ld8 r19=[r15],16 // pr
|
||||
ld8 r20=[r14],16 // pfs (syscall stub)
|
||||
mov b6=r18
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
ld8 r21=[r15],24 // bspstore
|
||||
ld8 r22=[r14],24 // rnat
|
||||
mov pr=r19,0x1fffe
|
||||
;;
|
||||
}
|
||||
{ .mmb
|
||||
ld8 r23=[r15],16 // tp
|
||||
ld8 r24=[r14],16 // rsc
|
||||
nop 0
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
ld8 r25=[r15],16 // fpsr
|
||||
ld8 r26=[r14],16 // psr
|
||||
mov ar.pfs=r20
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
ld8 gp=[r15],16 // gp
|
||||
ld8 r27=[r14],16 // ndirty
|
||||
tbit.z p14,p15=r26,34 // p14=ia64, p15=ia32
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
ld8 r28=[r15],56 // pfs (syscall caller)
|
||||
ld8 r29=[r14],56 // rp (syscall caller)
|
||||
shl r27=r27,16
|
||||
;;
|
||||
}
|
||||
{ .mmb
|
||||
ld8 r8=[r15],16 // r8
|
||||
mov ar.rsc=r27
|
||||
nop 0
|
||||
;;
|
||||
}
|
||||
{ .mmb
|
||||
ld8 r9=[r14],40 // r9
|
||||
ld8 r10=[r15],40 // r10
|
||||
(p15) br.spnt epc_syscall_setup_ia32
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
loadrs
|
||||
mov r14=ar.k5
|
||||
mov sp=r16
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
mov r30=ar.bspstore
|
||||
;;
|
||||
mov ar.bspstore=r21
|
||||
dep r30=0,r30,0,9
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
mov ar.k6=r30
|
||||
mov ar.k7=r31
|
||||
mov r13=r23
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
mov psr.l=r26
|
||||
mov ar.unat=r17
|
||||
add r14=gw_ret-ia64_gateway_page,r14
|
||||
;;
|
||||
}
|
||||
{ .mib
|
||||
srlz.d
|
||||
mov b7=r14
|
||||
br.ret.sptk b7
|
||||
;;
|
||||
}
|
||||
epc_syscall_setup_ia32:
|
||||
{ .mmi
|
||||
loadrs
|
||||
mov ar.k7=r31
|
||||
mov sp=r16
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
mov r30=ar.bspstore
|
||||
;;
|
||||
mov ar.bspstore=r21
|
||||
dep r30=0,r30,0,9
|
||||
;;
|
||||
}
|
||||
{ .mmi
|
||||
mov ar.k6=r30
|
||||
mov ar.unat=r17
|
||||
mov r11=r26
|
||||
;;
|
||||
}
|
||||
|
||||
ld8 r16=[r14],16
|
||||
ld8 r17=[r15],16
|
||||
;;
|
||||
ld8 r18=[r14],16
|
||||
ld8 r19=[r15],16
|
||||
;;
|
||||
ld8 r20=[r14],16
|
||||
ld8 r21=[r15],16
|
||||
;;
|
||||
ld8 r22=[r14],16
|
||||
ld8 r23=[r15],16
|
||||
;;
|
||||
ld8 r24=[r14],16
|
||||
ld8 r25=[r15],16
|
||||
;;
|
||||
ld8 r26=[r14],16
|
||||
ld8 r27=[r15],16
|
||||
;;
|
||||
ld8 r28=[r14],16
|
||||
ld8 r29=[r15],16
|
||||
;;
|
||||
ld8 r30=[r14],40
|
||||
ld8 r31=[r15],40
|
||||
;;
|
||||
ld8 r2=[r14],16
|
||||
ld8 r3=[r15],8
|
||||
;;
|
||||
mov ar.csd=r2
|
||||
mov ar.ssd=r3
|
||||
;;
|
||||
mov r2=ar.k5
|
||||
mov psr.l=r11
|
||||
;;
|
||||
srlz.d
|
||||
add r2=gw_ret_ia32-ia64_gateway_page,r2
|
||||
;;
|
||||
mov b7=r2
|
||||
br.ret.sptk b7
|
||||
;;
|
||||
END(epc_syscall)
|
||||
Loading…
Reference in New Issue
Block a user