How do exceptions work (behind the scenes) in c++

class MyException
{
public:
    MyException() { }
    ~MyException() { }
};

void my_throwing_function(bool throwit)
{
    if (throwit)
    	throw MyException();
}

void another_function();
void log(unsigned count);

void my_catching_function()
{
    log(0);
    try
    {
    	log(1);
    	another_function();
    	log(2);
    }
    catch (const MyException& e)
    {
    	log(3);
    }
    log(4);
}

.file	"foo.cpp"
    .section	.text._ZN11MyExceptionD1Ev,"axG",@progbits,_ZN11MyExceptionD1Ev,comdat
    .align 2
    .p2align 4,,15
    .weak	_ZN11MyExceptionD1Ev
    .type	_ZN11MyExceptionD1Ev, @function
_ZN11MyExceptionD1Ev:
.LFB7:
    pushl	%ebp
.LCFI0:
    movl	%esp, %ebp
.LCFI1:
    popl	%ebp
    ret
.LFE7:
    .size	_ZN11MyExceptionD1Ev, .-_ZN11MyExceptionD1Ev

.globl __gxx_personality_v0
.globl _Unwind_Resume
    .text
    .align 2
    .p2align 4,,15
.globl _Z20my_catching_functionv
    .type	_Z20my_catching_functionv, @function
_Z20my_catching_functionv:
.LFB9:
    pushl	%ebp
.LCFI2:
    movl	%esp, %ebp
.LCFI3:
    pushl	%ebx
.LCFI4:
    subl	$20, %esp
.LCFI5:
    movl	$0, (%esp)
.LEHB0:
    call	_Z3logj
.LEHE0:
    movl	$1, (%esp)
.LEHB1:
    call	_Z3logj
    call	_Z16another_functionv
    movl	$2, (%esp)
    call	_Z3logj
.LEHE1:
.L5:
    movl	$4, (%esp)
.LEHB2:
    call	_Z3logj
    addl	$20, %esp
    popl	%ebx
    popl	%ebp
    ret
.L12:
    subl	$1, %edx
    movl	%eax, %ebx
    je	.L16
.L14:
    movl	%ebx, (%esp)
    call	_Unwind_Resume
.LEHE2:
.L16:
.L6:
    movl	%eax, (%esp)
    call	__cxa_begin_catch
    movl	$3, (%esp)
.LEHB3:
    call	_Z3logj
.LEHE3:
    call	__cxa_end_catch
    .p2align 4,,3
    jmp	.L5
.L11:
.L8:
    movl	%eax, %ebx
    .p2align 4,,6
    call	__cxa_end_catch
    .p2align 4,,6
    jmp	.L14
.LFE9:
    .size	_Z20my_catching_functionv, .-_Z20my_catching_functionv
    .section	.gcc_except_table,"a",@progbits
    .align 4
.LLSDA9:
    .byte	0xff
    .byte	0x0
    .uleb128 .LLSDATT9-.LLSDATTD9
.LLSDATTD9:
    .byte	0x1
    .uleb128 .LLSDACSE9-.LLSDACSB9
.LLSDACSB9:
    .uleb128 .LEHB0-.LFB9
    .uleb128 .LEHE0-.LEHB0
    .uleb128 0x0
    .uleb128 0x0
    .uleb128 .LEHB1-.LFB9
    .uleb128 .LEHE1-.LEHB1
    .uleb128 .L12-.LFB9
    .uleb128 0x1
    .uleb128 .LEHB2-.LFB9
    .uleb128 .LEHE2-.LEHB2
    .uleb128 0x0
    .uleb128 0x0
    .uleb128 .LEHB3-.LFB9
    .uleb128 .LEHE3-.LEHB3
    .uleb128 .L11-.LFB9
    .uleb128 0x0
.LLSDACSE9:
    .byte	0x1
    .byte	0x0
    .align 4
    .long	_ZTI11MyException
.LLSDATT9:

.text
    .align 2
    .p2align 4,,15
.globl _Z20my_throwing_functionb
    .type	_Z20my_throwing_functionb, @function
_Z20my_throwing_functionb:
.LFB8:
    pushl	%ebp
.LCFI6:
    movl	%esp, %ebp
.LCFI7:
    subl	$24, %esp
.LCFI8:
    cmpb	$0, 8(%ebp)
    jne	.L21
    leave
    ret
.L21:
    movl	$1, (%esp)
    call	__cxa_allocate_exception
    movl	$_ZN11MyExceptionD1Ev, 8(%esp)
    movl	$_ZTI11MyException, 4(%esp)
    movl	%eax, (%esp)
    call	__cxa_throw
.LFE8:
    .size	_Z20my_throwing_functionb, .-_Z20my_throwing_functionb

.weak	_ZTI11MyException
    .section	.rodata._ZTI11MyException,"aG",@progbits,_ZTI11MyException,comdat
    .align 4
    .type	_ZTI11MyException, @object
    .size	_ZTI11MyException, 8
_ZTI11MyException:
    .long	_ZTVN10__cxxabiv117__class_type_infoE+8
    .long	_ZTS11MyException
    .weak	_ZTS11MyException
    .section	.rodata._ZTS11MyException,"aG",@progbits,_ZTS11MyException,comdat
    .type	_ZTS11MyException, @object
    .size	_ZTS11MyException, 14
_ZTS11MyException:
    .string	"11MyException"

.section	.eh_frame,"a",@progbits
.Lframe1:
    .long	.LECIE1-.LSCIE1
.LSCIE1:
    .long	0x0
    .byte	0x1
    .string	"zPL"
    .uleb128 0x1
    .sleb128 -4
    .byte	0x8
    .uleb128 0x6
    .byte	0x0
    .long	__gxx_personality_v0
    .byte	0x0
    .byte	0xc
    .uleb128 0x4
    .uleb128 0x4
    .byte	0x88
    .uleb128 0x1
    .align 4
.LECIE1:
.LSFDE3:
    .long	.LEFDE3-.LASFDE3
.LASFDE3:
    .long	.LASFDE3-.Lframe1
    .long	.LFB9
    .long	.LFE9-.LFB9
    .uleb128 0x4
    .long	.LLSDA9
    .byte	0x4
    .long	.LCFI2-.LFB9
    .byte	0xe
    .uleb128 0x8
    .byte	0x85
    .uleb128 0x2
    .byte	0x4
    .long	.LCFI3-.LCFI2
    .byte	0xd
    .uleb128 0x5
    .byte	0x4
    .long	.LCFI5-.LCFI3
    .byte	0x83
    .uleb128 0x3
    .align 4
.LEFDE3:
.LSFDE5:
    .long	.LEFDE5-.LASFDE5
.LASFDE5:
    .long	.LASFDE5-.Lframe1
    .long	.LFB8
    .long	.LFE8-.LFB8
    .uleb128 0x4
    .long	0x0
    .byte	0x4
    .long	.LCFI6-.LFB8
    .byte	0xe
    .uleb128 0x8
    .byte	0x85
    .uleb128 0x2
    .byte	0x4
    .long	.LCFI7-.LCFI6
    .byte	0xd
    .uleb128 0x5
    .align 4
.LEFDE5:
    .ident	"GCC: (GNU) 4.1.2 (Ubuntu 4.1.2-0ubuntu4)"
    .section	.note.GNU-stack,"",@progbits