/*--------------------------------------------------------------------*/
/*--- The core dispatch loop, for jumping to a code address. ---*/
/*--- dispatch-arm64-linux.S ---*/
/*--------------------------------------------------------------------*/
/*
This file is part of Valgrind, a dynamic binary instrumentation
framework.
Copyright (C) 2013-2013 OpenWorks
info@open-works.net
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
This program 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
General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307, USA.
The GNU General Public License is contained in the file COPYING.
*/
#if defined(VGP_arm64_linux)
#include "pub_core_basics_asm.h"
#include "pub_core_dispatch_asm.h"
#include "pub_core_transtab_asm.h"
#include "libvex_guest_offsets.h" /* for OFFSET_arm_R* */
/*------------------------------------------------------------*/
/*--- ---*/
/*--- The dispatch loop. VG_(disp_run_translations) is ---*/
/*--- used to run all translations, ---*/
/*--- including no-redir ones. ---*/
/*--- ---*/
/*------------------------------------------------------------*/
/*----------------------------------------------------*/
/*--- Entry and preamble (set everything up) ---*/
/*----------------------------------------------------*/
/* signature:
void VG_(disp_run_translations)( UWord* two_words,
void* guest_state,
Addr host_addr );
*/
.text
.global VG_(disp_run_translations)
VG_(disp_run_translations):
/* x0 holds two_words
x1 holds guest_state
x2 holds host_addr
*/
/* Push the callee-saved registers. Unclear if x19/x20 are
callee-saved, but be on the safe side. Note this sequence
maintains 16-alignment of sp. Also save x0 since it will
be needed in the postamble. */
stp x29, x30, [sp, #-16]!
stp x27, x28, [sp, #-16]!
stp x25, x26, [sp, #-16]!
stp x23, x24, [sp, #-16]!
stp x21, x22, [sp, #-16]!
stp x19, x20, [sp, #-16]!
stp x0, xzr, [sp, #-16]!
/* set FPSCR to vex-required default value */
// FIXME
// mov r4, #0
// fmxr fpscr, r4
/* Set up the guest state pointer */
mov x21, x1
/* and jump into the code cache. Chained translations in
the code cache run, until for whatever reason, they can't
continue. When that happens, the translation in question
will jump (or call) to one of the continuation points
VG_(cp_...) below. */
br x2
/* NOTREACHED */
/*----------------------------------------------------*/
/*--- Postamble and exit. ---*/
/*----------------------------------------------------*/
postamble:
/* At this point, r1 and r2 contain two
words to be returned to the caller. r1
holds a TRC value, and r2 optionally may
hold another word (for CHAIN_ME exits, the
address of the place to patch.) */
/* We're leaving. Check that nobody messed with
FPSCR in ways we don't expect. */
// FIXME
// fmrx r4, fpscr
// bic r4, #0xF8000000 /* mask out NZCV and QC */
// bic r4, #0x0000009F /* mask out IDC,IXC,UFC,OFC,DZC,IOC */
// cmp r4, #0
// beq remove_frame /* we're OK */
/* otherwise we have an invariant violation */
// movw r1, #VG_TRC_INVARIANT_FAILED
// movw r2, #0
/* fall through */
remove_frame:
/* Restore int regs, including importantly x0 (two_words),
but not x1 */
ldp x0, xzr, [sp], #16
ldp x19, x20, [sp], #16
ldp x21, x22, [sp], #16
ldp x23, x24, [sp], #16
ldp x25, x26, [sp], #16
ldp x27, x28, [sp], #16
ldp x29, x30, [sp], #16
/* Stash return values */
str x1, [x0, #0]
str x2, [x0, #8]
ret
/*----------------------------------------------------*/
/*--- Continuation points ---*/
/*----------------------------------------------------*/
/* ------ Chain me to slow entry point ------ */
.global VG_(disp_cp_chain_me_to_slowEP)
VG_(disp_cp_chain_me_to_slowEP):
/* We got called. The return address indicates
where the patching needs to happen. Collect
the return address and, exit back to C land,
handing the caller the pair (Chain_me_S, RA) */
mov x1, #VG_TRC_CHAIN_ME_TO_SLOW_EP
mov x2, x30 // 30 == LR
/* 4 = movw x9, disp_cp_chain_me_to_slowEP[15:0]
4 = movk x9, disp_cp_chain_me_to_slowEP[31:16], lsl 16
4 = movk x9, disp_cp_chain_me_to_slowEP[47:32], lsl 32
4 = movk x9, disp_cp_chain_me_to_slowEP[63:48], lsl 48
4 = blr x9
*/
sub x2, x2, #4+4+4+4+4
b postamble
/* ------ Chain me to fast entry point ------ */
.global VG_(disp_cp_chain_me_to_fastEP)
VG_(disp_cp_chain_me_to_fastEP):
/* We got called. The return address indicates
where the patching needs to happen. Collect
the return address and, exit back to C land,
handing the caller the pair (Chain_me_F, RA) */
mov x1, #VG_TRC_CHAIN_ME_TO_FAST_EP
mov x2, x30 // 30 == LR
/* 4 = movw x9, disp_cp_chain_me_to_fastEP[15:0]
4 = movk x9, disp_cp_chain_me_to_fastEP[31:16], lsl 16
4 = movk x9, disp_cp_chain_me_to_fastEP[47:32], lsl 32
4 = movk x9, disp_cp_chain_me_to_fastEP[63:48], lsl 48
4 = blr x9
*/
sub x2, x2, #4+4+4+4+4
b postamble
/* ------ Indirect but boring jump ------ */
.global VG_(disp_cp_xindir)
VG_(disp_cp_xindir):
/* Where are we going? */
ldr x0, [x21, #OFFSET_arm64_PC]
/* stats only */
adrp x1, VG_(stats__n_xindirs_32)
add x1, x1, :lo12:VG_(stats__n_xindirs_32)
ldr w2, [x1, #0]
add w2, w2, #1
str w2, [x1, #0]
/* try a fast lookup in the translation cache */
// x0 = next guest, x1,x2,x3,x4 scratch
mov x1, #VG_TT_FAST_MASK // x1 = VG_TT_FAST_MASK
and x2, x1, x0, LSR #2 // x2 = entry # = (x1 & (x0 >> 2))
adrp x4, VG_(tt_fast)
add x4, x4, :lo12:VG_(tt_fast) // x4 = &VG_(tt_fast)
add x1, x4, x2, LSL #4 // r1 = &tt_fast[entry#]
ldp x4, x5, [x1, #0] // x4 = .guest, x5 = .host
cmp x4, x0
// jump to host if lookup succeeded
bne fast_lookup_failed
br x5
/*NOTREACHED*/
fast_lookup_failed:
/* RM ME -- stats only */
adrp x1, VG_(stats__n_xindir_misses_32)
add x1, x1, :lo12:VG_(stats__n_xindir_misses_32)
ldr w2, [x1, #0]
add w2, w2, #1
str w2, [x1, #0]
mov x1, #VG_TRC_INNER_FASTMISS
mov x2, #0
b postamble
/* ------ Assisted jump ------ */
.global VG_(disp_cp_xassisted)
VG_(disp_cp_xassisted):
/* x21 contains the TRC */
mov x1, x21
mov x2, #0
b postamble
/* ------ Event check failed ------ */
.global VG_(disp_cp_evcheck_fail)
VG_(disp_cp_evcheck_fail):
mov x1, #VG_TRC_INNER_COUNTERZERO
mov x2, #0
b postamble
.size VG_(disp_run_translations), .-VG_(disp_run_translations)
/* Let the linker know we don't need an executable stack */
.section .note.GNU-stack,"",%progbits
#endif // defined(VGP_arm64_linux)
/*--------------------------------------------------------------------*/
/*--- end dispatch-arm64-linux.S ---*/
/*--------------------------------------------------------------------*/