#

# Copyright (c) 2012, Red Hat. All rights reserved.

# DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

#

# This code is free software; you can redistribute it and/or modify it

# under the terms of the GNU General Public License version 2 only, as

# published by the Free Software Foundation.

#

# This code 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

# version 2 for more details (a copy is included in the LICENSE file that

# accompanied this code).

#

# You should have received a copy of the GNU General Public License version

# 2 along with this work; if not, write to the Free Software Foundation,

# Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

#

# Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

# or visit www.oracle.com if you need additional information or have any

# questions.

# Routines used to enable x86 VM C++ code to invoke JIT-compiled ARM code

# -- either Java methods or generated stub -- and to allow JIT-compiled

# ARM code to invoke x86 VM C++ code

#

# the code for aarch64_stub_prolog below can be copied into the start

# of the ARM code buffer and patched with a link to the

# C++ routine which starts execution on the simulator. the ARM

# code can be generated immediately following the copied code.

#ifdef BUILTIN_SIM

	.data

        .globl setup_arm_sim,

	.type  setup_arm_sim,@function

        .globl get_alt_stack,

	.type  get_alt_stack,@function

        .globl aarch64_stub_prolog

        .p2align  4

aarch64_stub_prolog:

	// entry point

4:	lea 1f(%rip), %r11

	mov (%r11), %r10

	mov (%r10), %r10

	jmp *%r10

	.p2align 4

1:

	.set entry_offset, . - 1b

	.quad aarch64_prolog_ptr

	// 64 bit int used to idenitfy called fn arg/return types

	.set calltype_offset, . - 1b

	.quad 0

	// arm JIT code follows the stub

	.set arm_code_offset, . - 1b

	.size aarch64_stub_prolog, .-aarch64_stub_prolog

aarch64_stub_prolog_end:

	.text

aarch64_prolog_ptr:

	.quad aarch64_prolog

        .globl aarch64_prolog

aarch64_prolog:

	.cfi_startproc

	pushq	%rbp

	.cfi_def_cfa_offset 16

	.cfi_offset 6, -16

	movq	%rsp, %rbp

	.cfi_def_cfa_register 6

	// save all registers used to pass args

	sub $8, %rsp

	movd %xmm7, (%rsp)

	sub $8, %rsp

	movd %xmm6, (%rsp)

	sub $8, %rsp

	movd %xmm5, (%rsp)

	sub $8, %rsp

	movd %xmm4, (%rsp)

	sub $8, %rsp

	movd %xmm3, (%rsp)

	sub $8, %rsp

	movd %xmm2, (%rsp)

	sub $8, %rsp

	movd %xmm1, (%rsp)

	sub $8, %rsp

	movd %xmm0, (%rsp)

	push %r9

	push %r8

	push %rcx

	push %rdx

	push %rsi

	push %rdi

	// save rax -- this stack slot will be rewritten with a

	// return value if needed

	push %rax

	// temporarily save r11 while we find the other stack

	push %r11

	// retrieve alt stack

	call get_alt_stack@PLT

	pop %r11

	// push start of arm code

	lea (arm_code_offset)(%r11), %rsi

	push %rsi

	// load call type code in arg reg 1

	mov (calltype_offset)(%r11), %rsi

	// load current stack pointer in arg reg 0

	mov %rsp, %rdi

	// switch to alt stack

	mov %rax, %rsp

	// save previous stack pointer on new stack

	push %rdi

	// 16-align the new stack pointer

	push %rdi

	// call sim setup routine

	call setup_arm_sim@PLT

	// switch back to old stack

	pop %rsp

	// pop start of arm code

	pop %rdi

	// pop rax -- either restores old value or installs return value

	pop %rax

	// pop arg registers

	pop %rdi

	pop %rsi

	pop %rdx

	pop %rcx

	pop %r8

	pop %r9

	movd (%rsp), %xmm0

	add $8, %rsp

	movd (%rsp), %xmm1

	add $8, %rsp

	movd (%rsp), %xmm2

	add $8, %rsp

	movd (%rsp), %xmm3

	add $8, %rsp

	movd (%rsp), %xmm4

	add $8, %rsp

	movd (%rsp), %xmm5

	add $8, %rsp

	movd (%rsp), %xmm6

	add $8, %rsp

	movd (%rsp), %xmm7

	add $8, %rsp

	leave

	.cfi_def_cfa 7, 8

	ret

	.cfi_endproc

        .p2align  4

get_pc:

	// get return pc in rdi and then push it back

	pop %rdi

	push %rdi

	ret

	.p2align 4

	.long

	.globl aarch64_stub_prolog_size

	.type  aarch64_stub_prolog_size,@function

aarch64_stub_prolog_size:

	leaq  aarch64_stub_prolog_end - aarch64_stub_prolog, %rax

	ret

#endif