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/* ---------------------------------------------- */
/* alloca86.S */

.globl alloca

alloca:
    pop     %edx
    pop     %eax
    add     $3,%eax
    and     $-4,%eax
    jz      p3

#ifdef TCC_TARGET_PE
p1:
    cmp     $4096,%eax
    jbe     p2
    test    %eax,-4096(%esp)
    sub     $4096,%esp
    sub     $4096,%eax
    jmp p1
p2:
#endif

    sub     %eax,%esp
    mov     %esp,%eax
p3:
    push    %edx
    push    %edx
    ret

/* mark stack as nonexecutable */
#if defined __ELF__ && defined __linux__
    .section    .note.GNU-stack,"",@progbits
#endif
/* ---------------------------------------------- */