ref: 2bbc75bddc6f2a07056ff017108e35f14061041b
dir: /third_party/boringssl/src/crypto/test/asm/trampoline-x86_64.pl/
#!/usr/bin/env perl
# Copyright (c) 2018, 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 x86_64. 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 (Mac), or equivalent is
# used.
#
# References:
#
# SysV ABI: https://github.com/hjl-tools/x86-psABI/wiki/x86-64-psABI-1.0.pdf
# Win64 ABI: https://docs.microsoft.com/en-us/cpp/build/x64-software-conventions?view=vs-2017
use strict;
my $flavour = shift;
my $output = shift;
if ($flavour =~ /\./) { $output = $flavour; undef $flavour; }
my $win64 = 0;
$win64 = 1 if ($flavour =~ /[nm]asm|mingw64/ || $output =~ /\.asm$/);
$0 =~ m/(.*[\/\\])[^\/\\]+$/;
my $dir = $1;
my $xlate;
( $xlate="${dir}x86_64-xlate.pl" and -f $xlate ) or
( $xlate="${dir}../../perlasm/x86_64-xlate.pl" and -f $xlate) or
die "can't locate x86_64-xlate.pl";
open OUT, "| \"$^X\" \"$xlate\" $flavour \"$output\"";
*STDOUT = *OUT;
# @inp is the registers used for function inputs, in order.
my @inp = $win64 ? ("%rcx", "%rdx", "%r8", "%r9") :
("%rdi", "%rsi", "%rdx", "%rcx", "%r8", "%r9");
# @caller_state is the list of registers that the callee must preserve for the
# caller. This must match the definition of CallerState in abi_test.h.
my @caller_state = ("%rbx", "%rbp", "%r12", "%r13", "%r14", "%r15");
if ($win64) {
@caller_state = ("%rbx", "%rbp", "%rdi", "%rsi", "%r12", "%r13", "%r14",
"%r15", "%xmm6", "%xmm7", "%xmm8", "%xmm9", "%xmm10",
"%xmm11", "%xmm12", "%xmm13", "%xmm14", "%xmm15");
}
# $caller_state_size is the size of CallerState, in bytes.
my $caller_state_size = 0;
foreach (@caller_state) {
if (/^%r/) {
$caller_state_size += 8;
} elsif (/^%xmm/) {
$caller_state_size += 16;
} else {
die "unknown register $_";
}
}
# load_caller_state returns code which loads a CallerState structure at
# $off($reg) into the respective registers. No other registers are touched, but
# $reg may not be a register in CallerState. $cb is an optional callback to
# add extra lines after each movq or movdqa. $cb is passed the offset, relative
# to $reg, and name of each register.
sub load_caller_state {
my ($off, $reg, $cb) = @_;
my $ret = "";
foreach (@caller_state) {
my $old_off = $off;
if (/^%r/) {
$ret .= "\tmovq\t$off($reg), $_\n";
$off += 8;
} elsif (/^%xmm/) {
$ret .= "\tmovdqa\t$off($reg), $_\n";
$off += 16;
} else {
die "unknown register $_";
}
$ret .= $cb->($old_off, $_) if (defined($cb));
}
return $ret;
}
# store_caller_state behaves like load_caller_state, except that it writes the
# current values of the registers into $off($reg).
sub store_caller_state {
my ($off, $reg, $cb) = @_;
my $ret = "";
foreach (@caller_state) {
my $old_off = $off;
if (/^%r/) {
$ret .= "\tmovq\t$_, $off($reg)\n";
$off += 8;
} elsif (/^%xmm/) {
$ret .= "\tmovdqa\t$_, $off($reg)\n";
$off += 16;
} else {
die "unknown register $_";
}
$ret .= $cb->($old_off, $_) if (defined($cb));
}
return $ret;
}
# $max_params is the maximum number of parameters abi_test_trampoline supports.
my $max_params = 10;
# Windows reserves stack space for the register-based parameters, while SysV
# only reserves space for the overflow ones.
my $stack_params_skip = $win64 ? scalar(@inp) : 0;
my $num_stack_params = $win64 ? $max_params : $max_params - scalar(@inp);
my ($func, $state, $argv, $argc, $unwind) = @inp;
my $code = <<____;
.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|. If |unwind| is non-zero, this function triggers unwind
# instrumentation.
# uint64_t abi_test_trampoline(void (*func)(...), CallerState *state,
# const uint64_t *argv, size_t argc,
# int unwind);
.type abi_test_trampoline, \@abi-omnipotent
.globl abi_test_trampoline
.align 16
abi_test_trampoline:
.Labi_test_trampoline_seh_begin:
.cfi_startproc
# Stack layout:
# 8 bytes - align
# $caller_state_size bytes - saved caller registers
# 8 bytes - scratch space
# 8 bytes - saved copy of \$unwind (SysV-only)
# 8 bytes - saved copy of \$state
# 8 bytes - saved copy of \$func
# 8 bytes - if needed for stack alignment
# 8*$num_stack_params bytes - parameters for \$func
____
my $stack_alloc_size = 8 + $caller_state_size + 8*3 + 8*$num_stack_params;
if (!$win64) {
$stack_alloc_size += 8;
}
# SysV and Windows both require the stack to be 16-byte-aligned. The call
# instruction offsets it by 8, so stack allocations must be 8 mod 16.
if ($stack_alloc_size % 16 != 8) {
$num_stack_params++;
$stack_alloc_size += 8;
}
my $stack_params_offset = 8 * $stack_params_skip;
my $func_offset = 8 * $num_stack_params;
my $state_offset = $func_offset + 8;
# On Win64, unwind is already passed in memory. On SysV, it is passed in as
# register and we must reserve stack space for it.
my ($unwind_offset, $scratch_offset);
if ($win64) {
$unwind_offset = $stack_alloc_size + 5*8;
$scratch_offset = $state_offset + 8;
} else {
$unwind_offset = $state_offset + 8;
$scratch_offset = $unwind_offset + 8;
}
my $caller_state_offset = $scratch_offset + 8;
$code .= <<____;
subq \$$stack_alloc_size, %rsp
.cfi_adjust_cfa_offset $stack_alloc_size
.Labi_test_trampoline_seh_prolog_alloc:
____
$code .= <<____ if (!$win64);
movq $unwind, $unwind_offset(%rsp)
____
# Store our caller's state. This is needed because we modify it ourselves, and
# also to isolate the test infrastruction from the function under test failing
# to save some register.
my %reg_offsets;
$code .= store_caller_state($caller_state_offset, "%rsp", sub {
my ($off, $reg) = @_;
$reg = substr($reg, 1);
$reg_offsets{$reg} = $off;
$off -= $stack_alloc_size + 8;
return <<____;
.cfi_offset $reg, $off
.Labi_test_trampoline_seh_prolog_$reg:
____
});
$code .= <<____;
.Labi_test_trampoline_seh_prolog_end:
____
$code .= load_caller_state(0, $state);
$code .= <<____;
# Stash \$func and \$state, so they are available after the call returns.
movq $func, $func_offset(%rsp)
movq $state, $state_offset(%rsp)
# Load parameters. Note this will clobber \$argv and \$argc, so we can
# only use non-parameter volatile registers. There are three, and they
# are the same between SysV and Win64: %rax, %r10, and %r11.
movq $argv, %r10
movq $argc, %r11
____
foreach (@inp) {
$code .= <<____;
dec %r11
js .Largs_done
movq (%r10), $_
addq \$8, %r10
____
}
$code .= <<____;
leaq $stack_params_offset(%rsp), %rax
.Largs_loop:
dec %r11
js .Largs_done
# This block should be:
# movq (%r10), %rtmp
# movq %rtmp, (%rax)
# There are no spare registers available, so we spill into the scratch
# space.
movq %r11, $scratch_offset(%rsp)
movq (%r10), %r11
movq %r11, (%rax)
movq $scratch_offset(%rsp), %r11
addq \$8, %r10
addq \$8, %rax
jmp .Largs_loop
.Largs_done:
movq $func_offset(%rsp), %rax
movq $unwind_offset(%rsp), %r10
testq %r10, %r10
jz .Lno_unwind
# Set the trap flag.
pushfq
orq \$0x100, 0(%rsp)
popfq
# Run an instruction to trigger a breakpoint immediately before the
# call.
nop
.globl abi_test_unwind_start
abi_test_unwind_start:
call *%rax
.globl abi_test_unwind_return
abi_test_unwind_return:
# Clear the trap flag. Note this assumes the trap flag was clear on
# entry. We do not support instrumenting an unwind-instrumented
# |abi_test_trampoline|.
pushfq
andq \$-0x101, 0(%rsp) # -0x101 is ~0x100
popfq
.globl abi_test_unwind_stop
abi_test_unwind_stop:
jmp .Lcall_done
.Lno_unwind:
call *%rax
.Lcall_done:
# Store what \$func did our state, so our caller can check.
movq $state_offset(%rsp), $state
____
$code .= store_caller_state(0, $state);
# Restore our caller's state.
$code .= load_caller_state($caller_state_offset, "%rsp", sub {
my ($off, $reg) = @_;
$reg = substr($reg, 1);
return ".cfi_restore\t$reg\n";
});
$code .= <<____;
addq \$$stack_alloc_size, %rsp
.cfi_adjust_cfa_offset -$stack_alloc_size
# %rax already contains \$func's return value, unmodified.
ret
.cfi_endproc
.Labi_test_trampoline_seh_end:
.size abi_test_trampoline,.-abi_test_trampoline
____
# abi_test_clobber_* zeros the corresponding register. These are used to test
# the ABI-testing framework.
foreach ("ax", "bx", "cx", "dx", "di", "si", "bp", 8..15) {
$code .= <<____;
.type abi_test_clobber_r$_, \@abi-omnipotent
.globl abi_test_clobber_r$_
.align 16
abi_test_clobber_r$_:
xorq %r$_, %r$_
ret
.size abi_test_clobber_r$_,.-abi_test_clobber_r$_
____
}
foreach (0..15) {
$code .= <<____;
.type abi_test_clobber_xmm$_, \@abi-omnipotent
.globl abi_test_clobber_xmm$_
.align 16
abi_test_clobber_xmm$_:
pxor %xmm$_, %xmm$_
ret
.size abi_test_clobber_xmm$_,.-abi_test_clobber_xmm$_
____
}
$code .= <<____;
# abi_test_bad_unwind_wrong_register preserves the ABI, but annotates the wrong
# register in unwind metadata.
# void abi_test_bad_unwind_wrong_register(void);
.type abi_test_bad_unwind_wrong_register, \@abi-omnipotent
.globl abi_test_bad_unwind_wrong_register
.align 16
abi_test_bad_unwind_wrong_register:
.cfi_startproc
.Labi_test_bad_unwind_wrong_register_seh_begin:
pushq %r12
.cfi_push %r13 # This should be %r12
.Labi_test_bad_unwind_wrong_register_seh_push_r13:
# Windows evaluates epilogs directly in the unwinder, rather than using
# unwind codes. Add a nop so there is one non-epilog point (immediately
# before the nop) where the unwinder can observe the mistake.
nop
popq %r12
.cfi_pop %r12
ret
.Labi_test_bad_unwind_wrong_register_seh_end:
.cfi_endproc
.size abi_test_bad_unwind_wrong_register,.-abi_test_bad_unwind_wrong_register
# abi_test_bad_unwind_temporary preserves the ABI, but temporarily corrupts the
# storage space for a saved register, breaking unwind.
# void abi_test_bad_unwind_temporary(void);
.type abi_test_bad_unwind_temporary, \@abi-omnipotent
.globl abi_test_bad_unwind_temporary
.align 16
abi_test_bad_unwind_temporary:
.cfi_startproc
.Labi_test_bad_unwind_temporary_seh_begin:
pushq %r12
.cfi_push %r12
.Labi_test_bad_unwind_temporary_seh_push_r12:
movq %r12, %rax
inc %rax
movq %rax, (%rsp)
# Unwinding from here is incorrect. Although %r12 itself has not been
# changed, the unwind codes say to look in (%rsp) instead.
movq %r12, (%rsp)
# Unwinding is now fixed.
popq %r12
.cfi_pop %r12
ret
.Labi_test_bad_unwind_temporary_seh_end:
.cfi_endproc
.size abi_test_bad_unwind_temporary,.-abi_test_bad_unwind_temporary
# abi_test_get_and_clear_direction_flag clears the direction flag. If the flag
# was previously set, it returns one. Otherwise, it returns zero.
# int abi_test_get_and_clear_direction_flag(void);
.type abi_test_set_direction_flag, \@abi-omnipotent
.globl abi_test_get_and_clear_direction_flag
abi_test_get_and_clear_direction_flag:
pushfq
popq %rax
andq \$0x400, %rax
shrq \$10, %rax
cld
ret
.size abi_test_get_and_clear_direction_flag,.-abi_test_get_and_clear_direction_flag
# abi_test_set_direction_flag sets the direction flag.
# void abi_test_set_direction_flag(void);
.type abi_test_set_direction_flag, \@abi-omnipotent
.globl abi_test_set_direction_flag
abi_test_set_direction_flag:
std
ret
.size abi_test_set_direction_flag,.-abi_test_set_direction_flag
____
if ($win64) {
$code .= <<____;
# abi_test_bad_unwind_epilog preserves the ABI, and correctly annotates the
# prolog, but the epilog does not match Win64's rules, breaking unwind during
# the epilog.
# void abi_test_bad_unwind_epilog(void);
.type abi_test_bad_unwind_epilog, \@abi-omnipotent
.globl abi_test_bad_unwind_epilog
.align 16
abi_test_bad_unwind_epilog:
.Labi_test_bad_unwind_epilog_seh_begin:
pushq %r12
.Labi_test_bad_unwind_epilog_seh_push_r12:
nop
# The epilog should begin here, but the nop makes it invalid.
popq %r12
nop
ret
.Labi_test_bad_unwind_epilog_seh_end:
.size abi_test_bad_unwind_epilog,.-abi_test_bad_unwind_epilog
____
# Add unwind metadata for SEH.
#
# TODO(davidben): This is all manual right now. Once we've added SEH tests,
# add support for emitting these in x86_64-xlate.pl, probably based on MASM
# and Yasm's unwind directives, and unify with CFI. (Sadly, NASM does not
# support these directives.) Then push that upstream to replace the
# error-prone and non-standard custom handlers.
# See https://docs.microsoft.com/en-us/cpp/build/struct-unwind-code?view=vs-2017
my $UWOP_PUSH_NONVOL = 0;
my $UWOP_ALLOC_LARGE = 1;
my $UWOP_ALLOC_SMALL = 2;
my $UWOP_SAVE_NONVOL = 4;
my $UWOP_SAVE_XMM128 = 8;
my %UWOP_REG_NUMBER = (rax => 0, rcx => 1, rdx => 2, rbx => 3, rsp => 4,
rbp => 5, rsi => 6, rdi => 7,
map(("r$_" => $_), (8..15)));
my $unwind_codes = "";
my $num_slots = 0;
foreach my $reg (reverse @caller_state) {
$reg = substr($reg, 1);
die "unknown register $reg" unless exists($reg_offsets{$reg});
if ($reg =~ /^r/) {
die "unknown register $reg" unless exists($UWOP_REG_NUMBER{$reg});
my $info = $UWOP_SAVE_NONVOL | ($UWOP_REG_NUMBER{$reg} << 4);
my $value = $reg_offsets{$reg} / 8;
$unwind_codes .= <<____;
.byte .Labi_test_trampoline_seh_prolog_$reg-.Labi_test_trampoline_seh_begin
.byte $info
.value $value
____
$num_slots += 2;
} elsif ($reg =~ /^xmm/) {
my $info = $UWOP_SAVE_XMM128 | (substr($reg, 3) << 4);
my $value = $reg_offsets{$reg} / 16;
$unwind_codes .= <<____;
.byte .Labi_test_trampoline_seh_prolog_$reg-.Labi_test_trampoline_seh_begin
.byte $info
.value $value
____
$num_slots += 2;
} else {
die "unknown register $reg";
}
}
if ($stack_alloc_size <= 128) {
my $info = $UWOP_ALLOC_SMALL | ((($stack_alloc_size - 8) / 8) << 4);
$unwind_codes .= <<____;
.byte .Labi_test_trampoline_seh_prolog_alloc-.Labi_test_trampoline_seh_begin
.byte $info
____
$num_slots++;
} else {
die "stack allocation needs three unwind slots" if ($stack_alloc_size > 512 * 1024 + 8);
my $info = $UWOP_ALLOC_LARGE;
my $value = $stack_alloc_size / 8;
$unwind_codes .= <<____;
.byte .Labi_test_trampoline_seh_prolog_alloc-.Labi_test_trampoline_seh_begin
.byte $info
.value $value
____
$num_slots += 2;
}
$code .= <<____;
.section .pdata
.align 4
# https://docs.microsoft.com/en-us/cpp/build/struct-runtime-function?view=vs-2017
.rva .Labi_test_trampoline_seh_begin
.rva .Labi_test_trampoline_seh_end
.rva .Labi_test_trampoline_seh_info
.rva .Labi_test_bad_unwind_wrong_register_seh_begin
.rva .Labi_test_bad_unwind_wrong_register_seh_end
.rva .Labi_test_bad_unwind_wrong_register_seh_info
.rva .Labi_test_bad_unwind_temporary_seh_begin
.rva .Labi_test_bad_unwind_temporary_seh_end
.rva .Labi_test_bad_unwind_temporary_seh_info
.rva .Labi_test_bad_unwind_epilog_seh_begin
.rva .Labi_test_bad_unwind_epilog_seh_end
.rva .Labi_test_bad_unwind_epilog_seh_info
.section .xdata
.align 8
.Labi_test_trampoline_seh_info:
# https://docs.microsoft.com/en-us/cpp/build/struct-unwind-info?view=vs-2017
.byte 1 # version 1, no flags
.byte .Labi_test_trampoline_seh_prolog_end-.Labi_test_trampoline_seh_begin
.byte $num_slots
.byte 0 # no frame register
$unwind_codes
.align 8
.Labi_test_bad_unwind_wrong_register_seh_info:
.byte 1 # version 1, no flags
.byte .Labi_test_bad_unwind_wrong_register_seh_push_r13-.Labi_test_bad_unwind_wrong_register_seh_begin
.byte 1 # one slot
.byte 0 # no frame register
.byte .Labi_test_bad_unwind_wrong_register_seh_push_r13-.Labi_test_bad_unwind_wrong_register_seh_begin
.byte @{[$UWOP_PUSH_NONVOL | ($UWOP_REG_NUMBER{r13} << 4)]}
.align 8
.Labi_test_bad_unwind_temporary_seh_info:
.byte 1 # version 1, no flags
.byte .Labi_test_bad_unwind_temporary_seh_push_r12-.Labi_test_bad_unwind_temporary_seh_begin
.byte 1 # one slot
.byte 0 # no frame register
.byte .Labi_test_bad_unwind_temporary_seh_push_r12-.Labi_test_bad_unwind_temporary_seh_begin
.byte @{[$UWOP_PUSH_NONVOL | ($UWOP_REG_NUMBER{r12} << 4)]}
.align 8
.Labi_test_bad_unwind_epilog_seh_info:
.byte 1 # version 1, no flags
.byte .Labi_test_bad_unwind_epilog_seh_push_r12-.Labi_test_bad_unwind_epilog_seh_begin
.byte 1 # one slot
.byte 0 # no frame register
.byte .Labi_test_bad_unwind_epilog_seh_push_r12-.Labi_test_bad_unwind_epilog_seh_begin
.byte @{[$UWOP_PUSH_NONVOL | ($UWOP_REG_NUMBER{r12} << 4)]}
____
}
print $code;
close STDOUT or die "error closing STDOUT: $!";