ref: 2bbc75bddc6f2a07056ff017108e35f14061041b
dir: /third_party/boringssl/src/crypto/test/asm/trampoline-armv8.pl/
#!/usr/bin/env perl
# Copyright (c) 2019, Google Inc.
#
# Permission to use, copy, modify, and/or distribute this software for any
# purpose with or without fee is hereby granted, provided that the above
# copyright notice and this permission notice appear in all copies.
#
# THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
# SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
# OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
# CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
# This file defines helper functions for crypto/test/abi_test.h on aarch64. See
# that header for details on how to use this.
#
# For convenience, this file is linked into libcrypto, where consuming builds
# already support architecture-specific sources. The static linker should drop
# this code in non-test binaries. This includes a shared library build of
# libcrypto, provided --gc-sections (ELF), -dead_strip (iOS), or equivalent is
# used.
#
# References:
#
# AAPCS64: http://infocenter.arm.com/help/topic/com.arm.doc.ihi0055b/IHI0055B_aapcs64.pdf
# iOS ARM64: https://developer.apple.com/library/archive/documentation/Xcode/Conceptual/iPhoneOSABIReference/Articles/ARM64FunctionCallingConventions.html
use strict;
my $flavour = shift;
my $output = shift;
if ($flavour =~ /\./) { $output = $flavour; undef $flavour; }
$0 =~ m/(.*[\/\\])[^\/\\]+$/;
my $dir = $1;
my $xlate;
( $xlate="${dir}arm-xlate.pl" and -f $xlate ) or
( $xlate="${dir}../../perlasm/arm-xlate.pl" and -f $xlate) or
die "can't locate arm-xlate.pl";
open OUT, "| \"$^X\" \"$xlate\" $flavour \"$output\"";
*STDOUT = *OUT;
my ($func, $state, $argv, $argc) = ("x0", "x1", "x2", "x3");
my $code = <<____;
#include <openssl/arm_arch.h>
.text
// abi_test_trampoline loads callee-saved registers from |state|, calls |func|
// with |argv|, then saves the callee-saved registers into |state|. It returns
// the result of |func|. The |unwind| argument is unused.
// uint64_t abi_test_trampoline(void (*func)(...), CallerState *state,
// const uint64_t *argv, size_t argc,
// uint64_t unwind);
.type abi_test_trampoline, %function
.globl abi_test_trampoline
.align 4
abi_test_trampoline:
.Labi_test_trampoline_begin:
AARCH64_SIGN_LINK_REGISTER
// Stack layout (low to high addresses)
// x29,x30 (16 bytes)
// d8-d15 (64 bytes)
// x19-x28 (80 bytes)
// $state (8 bytes)
// padding (8 bytes)
stp x29, x30, [sp, #-176]!
mov x29, sp
// Saved callee-saved registers and |state|.
stp d8, d9, [sp, #16]
stp d10, d11, [sp, #32]
stp d12, d13, [sp, #48]
stp d14, d15, [sp, #64]
stp x19, x20, [sp, #80]
stp x21, x22, [sp, #96]
stp x23, x24, [sp, #112]
stp x25, x26, [sp, #128]
stp x27, x28, [sp, #144]
str $state, [sp, #160]
// Load registers from |state|, with the exception of x29. x29 is the
// frame pointer and also callee-saved, but AAPCS64 allows platforms to
// mandate that x29 always point to a frame. iOS64 does so, which means
// we cannot fill x29 with entropy without violating ABI rules
// ourselves. x29 is tested separately below.
ldp d8, d9, [$state], #16
ldp d10, d11, [$state], #16
ldp d12, d13, [$state], #16
ldp d14, d15, [$state], #16
ldp x19, x20, [$state], #16
ldp x21, x22, [$state], #16
ldp x23, x24, [$state], #16
ldp x25, x26, [$state], #16
ldp x27, x28, [$state], #16
// Move parameters into temporary registers.
mov x9, $func
mov x10, $argv
mov x11, $argc
// Load parameters into registers.
cbz x11, .Largs_done
ldr x0, [x10], #8
subs x11, x11, #1
b.eq .Largs_done
ldr x1, [x10], #8
subs x11, x11, #1
b.eq .Largs_done
ldr x2, [x10], #8
subs x11, x11, #1
b.eq .Largs_done
ldr x3, [x10], #8
subs x11, x11, #1
b.eq .Largs_done
ldr x4, [x10], #8
subs x11, x11, #1
b.eq .Largs_done
ldr x5, [x10], #8
subs x11, x11, #1
b.eq .Largs_done
ldr x6, [x10], #8
subs x11, x11, #1
b.eq .Largs_done
ldr x7, [x10], #8
.Largs_done:
blr x9
// Reload |state| and store registers.
ldr $state, [sp, #160]
stp d8, d9, [$state], #16
stp d10, d11, [$state], #16
stp d12, d13, [$state], #16
stp d14, d15, [$state], #16
stp x19, x20, [$state], #16
stp x21, x22, [$state], #16
stp x23, x24, [$state], #16
stp x25, x26, [$state], #16
stp x27, x28, [$state], #16
// |func| is required to preserve x29, the frame pointer. We cannot load
// random values into x29 (see comment above), so compare it against the
// expected value and zero the field of |state| if corrupted.
mov x9, sp
cmp x29, x9
b.eq .Lx29_ok
str xzr, [$state]
.Lx29_ok:
// Restore callee-saved registers.
ldp d8, d9, [sp, #16]
ldp d10, d11, [sp, #32]
ldp d12, d13, [sp, #48]
ldp d14, d15, [sp, #64]
ldp x19, x20, [sp, #80]
ldp x21, x22, [sp, #96]
ldp x23, x24, [sp, #112]
ldp x25, x26, [sp, #128]
ldp x27, x28, [sp, #144]
ldp x29, x30, [sp], #176
AARCH64_VALIDATE_LINK_REGISTER
ret
.size abi_test_trampoline,.-abi_test_trampoline
____
# abi_test_clobber_* zeros the corresponding register. These are used to test
# the ABI-testing framework.
foreach (0..29) {
# x18 is the platform register and off limits.
next if ($_ == 18);
$code .= <<____;
.type abi_test_clobber_x$_, %function
.globl abi_test_clobber_x$_
.align 4
abi_test_clobber_x$_:
AARCH64_VALID_CALL_TARGET
mov x$_, xzr
ret
.size abi_test_clobber_x$_,.-abi_test_clobber_x$_
____
}
foreach (0..31) {
$code .= <<____;
.type abi_test_clobber_d$_, %function
.globl abi_test_clobber_d$_
.align 4
abi_test_clobber_d$_:
AARCH64_VALID_CALL_TARGET
fmov d$_, xzr
ret
.size abi_test_clobber_d$_,.-abi_test_clobber_d$_
____
}
# abi_test_clobber_v*_upper clobbers only the upper half of v*. AAPCS64 only
# requires the lower half (d*) be preserved.
foreach (8..15) {
$code .= <<____;
.type abi_test_clobber_v${_}_upper, %function
.globl abi_test_clobber_v${_}_upper
.align 4
abi_test_clobber_v${_}_upper:
AARCH64_VALID_CALL_TARGET
fmov v${_}.d[1], xzr
ret
.size abi_test_clobber_v${_}_upper,.-abi_test_clobber_v${_}_upper
____
}
print $code;
close STDOUT or die "error closing STDOUT: $!";