/*
 * cepis_abi_probe(fn, a0, a1, a2, a3)
 *
 * Calls fn(a0, a1, a2, a3) with every callee-saved register holding a
 * distinctive sentinel and returns a bitmask of the ones it came back
 * clobbered, plus bits for a moved stack pointer and a left-over direction
 * flag. 0 means the callee honoured the System V AMD64 ABI.
 *
 * Not part of the library: this file is only linked into the test driver.
 */

        .text
        .globl  cepis_abi_probe
        .type   cepis_abi_probe, @function
        .p2align 4
cepis_abi_probe:
        push    %rbp
        mov     %rsp, %rbp
        push    %rbx
        push    %r12
        push    %r13
        push    %r14
        push    %r15
        sub     $8, %rsp
        mov     %rbp, cepis__probe_bp(%rip)
        mov     %rsp, cepis__probe_sp(%rip)
        mov     %rdi, %rax
        mov     %rsi, %rdi
        mov     %rdx, %rsi
        mov     %rcx, %rdx
        mov     %r8, %rcx
        movabs  $0x1111111111111111, %rbx
        movabs  $0x2222222222222222, %r12
        movabs  $0x3333333333333333, %r13
        movabs  $0x4444444444444444, %r14
        movabs  $0x5555555555555555, %r15
        movabs  $0x6666666666666666, %rbp
        call    *%rax
        xor     %r8d, %r8d
        movabs  $0x1111111111111111, %r9
        cmp     %r9, %rbx
        je      .Lp_r12
        or      $1, %r8d
.Lp_r12:
        movabs  $0x2222222222222222, %r9
        cmp     %r9, %r12
        je      .Lp_r13
        or      $2, %r8d
.Lp_r13:
        movabs  $0x3333333333333333, %r9
        cmp     %r9, %r13
        je      .Lp_r14
        or      $4, %r8d
.Lp_r14:
        movabs  $0x4444444444444444, %r9
        cmp     %r9, %r14
        je      .Lp_r15
        or      $8, %r8d
.Lp_r15:
        movabs  $0x5555555555555555, %r9
        cmp     %r9, %r15
        je      .Lp_rbp
        or      $16, %r8d
.Lp_rbp:
        movabs  $0x6666666666666666, %r9
        cmp     %r9, %rbp
        je      .Lp_sp
        or      $32, %r8d
.Lp_sp:
        mov     cepis__probe_sp(%rip), %r9
        cmp     %r9, %rsp
        je      .Lp_df
        or      $64, %r8d
        mov     %r9, %rsp
.Lp_df:
        pushfq
        pop     %r9
        test    $0x400, %r9d
        jz      .Lp_done
        or      $128, %r8d
        cld
.Lp_done:
        mov     cepis__probe_bp(%rip), %rbp
        mov     %r8d, %eax
        lea     -40(%rbp), %rsp
        pop     %r15
        pop     %r14
        pop     %r13
        pop     %r12
        pop     %rbx
        pop     %rbp
        ret
        .size   cepis_abi_probe, . - cepis_abi_probe

        .data
        .p2align 3
cepis__probe_bp:
        .quad   0
cepis__probe_sp:
        .quad   0

        .section .note.GNU-stack,"",@progbits