;*****************************************************************************
;* Assembly testing and benchmarking tool
;* Copyright (c) 2008 Loren Merritt
;* Copyright (c) 2012 Henrik Gramner
;*
;* This file is part of Libav.
;*
;* Libav 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.
;*
;* Libav 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., 51 Franklin Street, Fifth Floor, Boston, MA  02111, USA.
;*****************************************************************************

%define private_prefix checkasm
%include "libavutil/x86/x86inc.asm"

SECTION_RODATA

error_message: db "failed to preserve register", 0
error_message_emms: db "failed to issue emms", 0

%if ARCH_X86_64
; just random numbers to reduce the chance of incidental match
ALIGN 16
x6:  dq 0x1a1b2550a612b48c,0x79445c159ce79064
x7:  dq 0x2eed899d5a28ddcd,0x86b2536fcd8cf636
x8:  dq 0xb0856806085e7943,0x3f2bf84fc0fcca4e
x9:  dq 0xacbd382dcf5b8de2,0xd229e1f5b281303f
x10: dq 0x71aeaff20b095fd9,0xab63e2e11fa38ed9
x11: dq 0x89b0c0765892729a,0x77d410d5c42c882d
x12: dq 0xc45ea11a955d8dd5,0x24b3c1d2a024048b
x13: dq 0x2e8ec680de14b47c,0xdd7b8919edd42786
x14: dq 0x135ce6888fa02cbf,0x11e53e2b2ac655ef
x15: dq 0x011ff554472a7a10,0x6de8f4c914c334d5
n7:  dq 0x21f86d66c8ca00ce
n8:  dq 0x75b6ba21077c48ad
n9:  dq 0xed56bb2dcb3c7736
n10: dq 0x8bda43d3fd1a7e06
n11: dq 0xb64a9c9e5d318408
n12: dq 0xdf9a54b303f1d3a3
n13: dq 0x4a75479abd64e097
n14: dq 0x249214109d5d1c88
%endif

SECTION .text

cextern fail_func

; max number of args used by any asm function.
; (max_args % 4) must equal 3 for stack alignment
%define max_args 15

%if ARCH_X86_64

;-----------------------------------------------------------------------------
; int checkasm_stack_clobber(uint64_t clobber, ...)
;-----------------------------------------------------------------------------
cglobal stack_clobber, 1,2
    ; Clobber the stack with junk below the stack pointer
    %define argsize (max_args+6)*8
    SUB  rsp, argsize
    mov   r1, argsize-8
.loop:
    mov [rsp+r1], r0
    sub   r1, 8
    jge .loop
    ADD  rsp, argsize
    RET

%if WIN64
    %assign free_regs 7
    DECLARE_REG_TMP 4
%else
    %assign free_regs 9
    DECLARE_REG_TMP 7
%endif

%macro report_fail 1
    mov  r9, rax
    mov r10, rdx
    lea  r0, [%1]
    xor eax, eax
    call fail_func
    mov rdx, r10
    mov rax, r9
%endmacro

;-----------------------------------------------------------------------------
; void checkasm_checked_call(void *func, ...)
;-----------------------------------------------------------------------------
INIT_XMM
%macro CHECKED_CALL 0-1
cglobal checked_call%1, 2,15,16,max_args*8+8
    mov  t0, r0

    ; All arguments have been pushed on the stack instead of registers in order to
    ; test for incorrect assumptions that 32-bit ints are zero-extended to 64-bit.
    mov  r0, r6mp
    mov  r1, r7mp
    mov  r2, r8mp
    mov  r3, r9mp
%if UNIX64
    mov  r4, r10mp
    mov  r5, r11mp
    %assign i 6
    %rep max_args-6
        mov  r9, [rsp+stack_offset+(i+1)*8]
        mov  [rsp+(i-6)*8], r9
        %assign i i+1
    %endrep
%else ; WIN64
    %assign i 4
    %rep max_args-4
        mov  r9, [rsp+stack_offset+(i+7)*8]
        mov  [rsp+i*8], r9
        %assign i i+1
    %endrep

    ; Move possible floating-point arguments to the correct registers
    movq m0, r0
    movq m1, r1
    movq m2, r2
    movq m3, r3

    %assign i 6
    %rep 16-6
        mova m %+ i, [x %+ i]
        %assign i i+1
    %endrep
%endif

%assign i 14
%rep 15-free_regs
    mov r %+ i, [n %+ i]
    %assign i i-1
%endrep
    call t0
%assign i 14
%rep 15-free_regs
    xor r %+ i, [n %+ i]
    or  r14, r %+ i
    %assign i i-1
%endrep

%if WIN64
    %assign i 6
    %rep 16-6
        pxor m %+ i, [x %+ i]
        por  m6, m %+ i
        %assign i i+1
    %endrep
    packsswb m6, m6
    movq r5, m6
    or  r14, r5
%endif

    ; Call fail_func() with a descriptive message to mark it as a failure
    ; if the called function didn't preserve all callee-saved registers.
    ; Save the return value located in rdx:rax first to prevent clobbering.
    jz .clobber_ok
    report_fail error_message
.clobber_ok:
%ifnid %1, _emms
    fstenv [rsp]
    cmp  word [rsp + 8], 0xffff
    je   .emms_ok
    report_fail error_message_emms
    emms
.emms_ok:
%else
    emms
%endif
    RET
%endmacro

%else

; just random numbers to reduce the chance of incidental match
%define n3 dword 0x6549315c
%define n4 dword 0xe02f3e23
%define n5 dword 0xb78d0d1d
%define n6 dword 0x33627ba7

%macro report_fail 1
    mov  r3, eax
    mov  r4, edx
    lea  r0, [%1]
    mov [esp], r0
    call fail_func
    mov  edx, r4
    mov  eax, r3
%endmacro

%macro CHECKED_CALL 0-1
;-----------------------------------------------------------------------------
; void checkasm_checked_call(void *func, ...)
;-----------------------------------------------------------------------------
cglobal checked_call%1, 1,7
    mov  r3, n3
    mov  r4, n4
    mov  r5, n5
    mov  r6, n6
%rep max_args
    PUSH dword [esp+20+max_args*4]
%endrep
    call r0
    xor  r3, n3
    xor  r4, n4
    xor  r5, n5
    xor  r6, n6
    or   r3, r4
    or   r5, r6
    or   r3, r5
    jz .clobber_ok
    report_fail error_message
.clobber_ok:
%ifnid %1, _emms
    fstenv [esp]
    cmp  word [esp + 8], 0xffff
    je   .emms_ok
    report_fail error_message_emms
    emms
.emms_ok:
%else
    emms
%endif
    add  esp, max_args*4
    REP_RET
%endmacro

%endif ; ARCH_X86_64

CHECKED_CALL
CHECKED_CALL _emms