PIC32MM bootloader process explanation

.reset _RESET_ADDR :
  {
    KEEP(*(.reset))
    KEEP(*(.reset.startup))
  } > kseg1_boot_mem
  .bev_excpt _BEV_EXCPT_ADDR :
  {
    KEEP(*(.bev_handler))
  } > kseg1_boot_mem
  /* Debug exception vector */
  .dbg_excpt _DBG_EXCPT_ADDR (NOLOAD) :
  {
    . += (DEFINED (_DEBUGGER) ? 0x8 : 0x0);
  } > kseg1_boot_mem
  /* Space reserved for the debug executive */
  .dbg_code _DBG_CODE_ADDR (NOLOAD) :
  {
    . += (DEFINED (_DEBUGGER) ? _DBG_CODE_SIZE : 0x0);
  } > debug_exec_mem

  .app_excpt _GEN_EXCPT_ADDR :
  {
    KEEP(*(.gen_handler))
  } > exception_mem

  .vector_0 _ebase_address + 0x200 + ((_vector_spacing << 5) * 0) :
  {
     KEEP(*(.vector_0))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_0) <= (_vector_spacing << 5), "function at exception vector 0 too large")
  .vector_1 _ebase_address + 0x200 + ((_vector_spacing << 5) * 1) :
  {
     KEEP(*(.vector_1))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_1) <= (_vector_spacing << 5), "function at exception vector 1 too large")
  .vector_2 _ebase_address + 0x200 + ((_vector_spacing << 5) * 2) :
  {
     KEEP(*(.vector_2))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_2) <= (_vector_spacing << 5), "function at exception vector 2 too large")
  .vector_3 _ebase_address + 0x200 + ((_vector_spacing << 5) * 3) :
  {
     KEEP(*(.vector_3))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_3) <= (_vector_spacing << 5), "function at exception vector 3 too large")
  .vector_4 _ebase_address + 0x200 + ((_vector_spacing << 5) * 4) :
  {
     KEEP(*(.vector_4))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_4) <= (_vector_spacing << 5), "function at exception vector 4 too large")
  .vector_5 _ebase_address + 0x200 + ((_vector_spacing << 5) * 5) :
  {
     KEEP(*(.vector_5))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_5) <= (_vector_spacing << 5), "function at exception vector 5 too large")
  .vector_6 _ebase_address + 0x200 + ((_vector_spacing << 5) * 6) :
  {
     KEEP(*(.vector_6))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_6) <= (_vector_spacing << 5), "function at exception vector 6 too large")
  .vector_7 _ebase_address + 0x200 + ((_vector_spacing << 5) * 7) :
  {
     KEEP(*(.vector_7))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_7) <= (_vector_spacing << 5), "function at exception vector 7 too large")
  .vector_8 _ebase_address + 0x200 + ((_vector_spacing << 5) * 8) :
  {
     KEEP(*(.vector_8))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_8) <= (_vector_spacing << 5), "function at exception vector 8 too large")
  .vector_9 _ebase_address + 0x200 + ((_vector_spacing << 5) * 9) :
  {
     KEEP(*(.vector_9))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_9) <= (_vector_spacing << 5), "function at exception vector 9 too large")
  .vector_10 _ebase_address + 0x200 + ((_vector_spacing << 5) * 10) :
  {
     KEEP(*(.vector_10))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_10) <= (_vector_spacing << 5), "function at exception vector 10 too large")
  .vector_11 _ebase_address + 0x200 + ((_vector_spacing << 5) * 11) :
  {
     KEEP(*(.vector_11))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_11) <= (_vector_spacing << 5), "function at exception vector 11 too large")
  .vector_12 _ebase_address + 0x200 + ((_vector_spacing << 5) * 12) :
  {
     KEEP(*(.vector_12))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_12) <= (_vector_spacing << 5), "function at exception vector 12 too large")
  .vector_13 _ebase_address + 0x200 + ((_vector_spacing << 5) * 13) :
  {
     KEEP(*(.vector_13))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_13) <= (_vector_spacing << 5), "function at exception vector 13 too large")
  .vector_14 _ebase_address + 0x200 + ((_vector_spacing << 5) * 14) :
  {
     KEEP(*(.vector_14))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_14) <= (_vector_spacing << 5), "function at exception vector 14 too large")
  .vector_15 _ebase_address + 0x200 + ((_vector_spacing << 5) * 15) :
  {
     KEEP(*(.vector_15))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_15) <= (_vector_spacing << 5), "function at exception vector 15 too large")
  .vector_16 _ebase_address + 0x200 + ((_vector_spacing << 5) * 16) :
  {
     KEEP(*(.vector_16))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_16) <= (_vector_spacing << 5), "function at exception vector 16 too large")
  .vector_17 _ebase_address + 0x200 + ((_vector_spacing << 5) * 17) :
  {
     KEEP(*(.vector_17))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_17) <= (_vector_spacing << 5), "function at exception vector 17 too large")
  .vector_18 _ebase_address + 0x200 + ((_vector_spacing << 5) * 18) :
  {
     KEEP(*(.vector_18))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_18) <= (_vector_spacing << 5), "function at exception vector 18 too large")
  .vector_19 _ebase_address + 0x200 + ((_vector_spacing << 5) * 19) :
  {
     KEEP(*(.vector_19))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_19) <= (_vector_spacing << 5), "function at exception vector 19 too large")
  .vector_20 _ebase_address + 0x200 + ((_vector_spacing << 5) * 20) :
  {
     KEEP(*(.vector_20))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_20) <= (_vector_spacing << 5), "function at exception vector 20 too large")
  .vector_21 _ebase_address + 0x200 + ((_vector_spacing << 5) * 21) :
  {
     KEEP(*(.vector_21))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_21) <= (_vector_spacing << 5), "function at exception vector 21 too large")
  .vector_22 _ebase_address + 0x200 + ((_vector_spacing << 5) * 22) :
  {
     KEEP(*(.vector_22))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_22) <= (_vector_spacing << 5), "function at exception vector 22 too large")
  .vector_23 _ebase_address + 0x200 + ((_vector_spacing << 5) * 23) :
  {
     KEEP(*(.vector_23))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_23) <= (_vector_spacing << 5), "function at exception vector 23 too large")
  .vector_24 _ebase_address + 0x200 + ((_vector_spacing << 5) * 24) :
  {
     KEEP(*(.vector_24))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_24) <= (_vector_spacing << 5), "function at exception vector 24 too large")
  .vector_25 _ebase_address + 0x200 + ((_vector_spacing << 5) * 25) :
  {
     KEEP(*(.vector_25))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_25) <= (_vector_spacing << 5), "function at exception vector 25 too large")
  .vector_26 _ebase_address + 0x200 + ((_vector_spacing << 5) * 26) :
  {
     KEEP(*(.vector_26))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_26) <= (_vector_spacing << 5), "function at exception vector 26 too large")
  .vector_27 _ebase_address + 0x200 + ((_vector_spacing << 5) * 27) :
  {
     KEEP(*(.vector_27))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_27) <= (_vector_spacing << 5), "function at exception vector 27 too large")
  .vector_28 _ebase_address + 0x200 + ((_vector_spacing << 5) * 28) :
  {
     KEEP(*(.vector_28))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_28) <= (_vector_spacing << 5), "function at exception vector 28 too large")
  .vector_29 _ebase_address + 0x200 + ((_vector_spacing << 5) * 29) :
  {
     KEEP(*(.vector_29))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_29) <= (_vector_spacing << 5), "function at exception vector 29 too large")
  .vector_30 _ebase_address + 0x200 + ((_vector_spacing << 5) * 30) :
  {
     KEEP(*(.vector_30))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_30) <= (_vector_spacing << 5), "function at exception vector 30 too large")
  .vector_31 _ebase_address + 0x200 + ((_vector_spacing << 5) * 31) :
  {
     KEEP(*(.vector_31))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_31) <= (_vector_spacing << 5), "function at exception vector 31 too large")
  .vector_32 _ebase_address + 0x200 + ((_vector_spacing << 5) * 32) :
  {
     KEEP(*(.vector_32))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_32) <= (_vector_spacing << 5), "function at exception vector 32 too large")
  .vector_33 _ebase_address + 0x200 + ((_vector_spacing << 5) * 33) :
  {
     KEEP(*(.vector_33))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_33) <= (_vector_spacing << 5), "function at exception vector 33 too large")
  .vector_34 _ebase_address + 0x200 + ((_vector_spacing << 5) * 34) :
  {
     KEEP(*(.vector_34))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_34) <= (_vector_spacing << 5), "function at exception vector 34 too large")
  .vector_35 _ebase_address + 0x200 + ((_vector_spacing << 5) * 35) :
  {
     KEEP(*(.vector_35))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_35) <= (_vector_spacing << 5), "function at exception vector 35 too large")
  .vector_36 _ebase_address + 0x200 + ((_vector_spacing << 5) * 36) :
  {
     KEEP(*(.vector_36))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_36) <= (_vector_spacing << 5), "function at exception vector 36 too large")
  .vector_37 _ebase_address + 0x200 + ((_vector_spacing << 5) * 37) :
  {
     KEEP(*(.vector_37))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_37) <= (_vector_spacing << 5), "function at exception vector 37 too large")
  .vector_38 _ebase_address + 0x200 + ((_vector_spacing << 5) * 38) :
  {
     KEEP(*(.vector_38))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_38) <= (_vector_spacing << 5), "function at exception vector 38 too large")
  .vector_39 _ebase_address + 0x200 + ((_vector_spacing << 5) * 39) :
  {
     KEEP(*(.vector_39))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_39) <= (_vector_spacing << 5), "function at exception vector 39 too large")
  .vector_40 _ebase_address + 0x200 + ((_vector_spacing << 5) * 40) :
  {
     KEEP(*(.vector_40))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_40) <= (_vector_spacing << 5), "function at exception vector 40 too large")
  .vector_41 _ebase_address + 0x200 + ((_vector_spacing << 5) * 41) :
  {
     KEEP(*(.vector_41))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_41) <= (_vector_spacing << 5), "function at exception vector 41 too large")
  .vector_42 _ebase_address + 0x200 + ((_vector_spacing << 5) * 42) :
  {
     KEEP(*(.vector_42))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_42) <= (_vector_spacing << 5), "function at exception vector 42 too large")
  .vector_43 _ebase_address + 0x200 + ((_vector_spacing << 5) * 43) :
  {
     KEEP(*(.vector_43))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_43) <= (_vector_spacing << 5), "function at exception vector 43 too large")
  .vector_44 _ebase_address + 0x200 + ((_vector_spacing << 5) * 44) :
  {
     KEEP(*(.vector_44))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_44) <= (_vector_spacing << 5), "function at exception vector 44 too large")
  .vector_45 _ebase_address + 0x200 + ((_vector_spacing << 5) * 45) :
  {
     KEEP(*(.vector_45))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_45) <= (_vector_spacing << 5), "function at exception vector 45 too large")
  .vector_46 _ebase_address + 0x200 + ((_vector_spacing << 5) * 46) :
  {
     KEEP(*(.vector_46))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_46) <= (_vector_spacing << 5), "function at exception vector 46 too large")
  .vector_47 _ebase_address + 0x200 + ((_vector_spacing << 5) * 47) :
  {
     KEEP(*(.vector_47))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_47) <= (_vector_spacing << 5), "function at exception vector 47 too large")
  .vector_48 _ebase_address + 0x200 + ((_vector_spacing << 5) * 48) :
  {
     KEEP(*(.vector_48))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_48) <= (_vector_spacing << 5), "function at exception vector 48 too large")
  .vector_49 _ebase_address + 0x200 + ((_vector_spacing << 5) * 49) :
  {
     KEEP(*(.vector_49))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_49) <= (_vector_spacing << 5), "function at exception vector 49 too large")
  .vector_50 _ebase_address + 0x200 + ((_vector_spacing << 5) * 50) :
  {
     KEEP(*(.vector_50))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_50) <= (_vector_spacing << 5), "function at exception vector 50 too large")
  .vector_51 _ebase_address + 0x200 + ((_vector_spacing << 5) * 51) :
  {
     KEEP(*(.vector_51))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_51) <= (_vector_spacing << 5), "function at exception vector 51 too large")
  .vector_52 _ebase_address + 0x200 + ((_vector_spacing << 5) * 52) :
  {
     KEEP(*(.vector_52))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_52) <= (_vector_spacing << 5), "function at exception vector 52 too large")
  .vector_53 _ebase_address + 0x200 + ((_vector_spacing << 5) * 53) :
  {
     KEEP(*(.vector_53))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_53) <= (_vector_spacing << 5), "function at exception vector 53 too large")
  .vector_54 _ebase_address + 0x200 + ((_vector_spacing << 5) * 54) :
  {
     KEEP(*(.vector_54))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_54) <= (_vector_spacing << 5), "function at exception vector 54 too large")
  .vector_55 _ebase_address + 0x200 + ((_vector_spacing << 5) * 55) :
  {
     KEEP(*(.vector_55))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_55) <= (_vector_spacing << 5), "function at exception vector 55 too large")
  .vector_56 _ebase_address + 0x200 + ((_vector_spacing << 5) * 56) :
  {
     KEEP(*(.vector_56))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_56) <= (_vector_spacing << 5), "function at exception vector 56 too large")
  .vector_57 _ebase_address + 0x200 + ((_vector_spacing << 5) * 57) :
  {
     KEEP(*(.vector_57))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_57) <= (_vector_spacing << 5), "function at exception vector 57 too large")
  .vector_58 _ebase_address + 0x200 + ((_vector_spacing << 5) * 58) :
  {
     KEEP(*(.vector_58))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_58) <= (_vector_spacing << 5), "function at exception vector 58 too large")
  .vector_59 _ebase_address + 0x200 + ((_vector_spacing << 5) * 59) :
  {
     KEEP(*(.vector_59))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_59) <= (_vector_spacing << 5), "function at exception vector 59 too large")
  .vector_60 _ebase_address + 0x200 + ((_vector_spacing << 5) * 60) :
  {
     KEEP(*(.vector_60))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_60) <= (_vector_spacing << 5), "function at exception vector 60 too large")
  .vector_61 _ebase_address + 0x200 + ((_vector_spacing << 5) * 61) :
  {
     KEEP(*(.vector_61))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_61) <= (_vector_spacing << 5), "function at exception vector 61 too large")
  .vector_62 _ebase_address + 0x200 + ((_vector_spacing << 5) * 62) :
  {
     KEEP(*(.vector_62))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_62) <= (_vector_spacing << 5), "function at exception vector 62 too large")
  .vector_63 _ebase_address + 0x200 + ((_vector_spacing << 5) * 63) :
  {
     KEEP(*(.vector_63))
  } > exception_mem
  ASSERT (_vector_spacing == 0 || SIZEOF(.vector_63) <= (_vector_spacing << 5), "function at exception vector 63 too large")