News:

Masm32 SDK description, downloads and other helpful links
Message to All Guests

Main Menu

Stackframe register preservation macros.

Started by hutch--, July 17, 2018, 01:31:34 PM

Previous topic - Next topic

hutch--

With thanks to both "sinsi" and "HSE", I have got a system that is clean and easy to use for preserving 64 bit registers (rax to r15) in a stackframe procedure. It tests OK, it is easy to use and it is thread safe. I have used the name "USING" for the macro that allocates the stack space as it has at least some familiarity with the USES notation but is free of the RSP alteration that PUSH and POP mnemonics produce.

; ¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤

    include \masm32\include64\masm64rt.inc

    MLOCAL equ LOCAL    ; the word LOCAL is ambiguous in a MACRO

  ; -------------------------------------------------------
  ; Register preservation macros for stack frame procedures
  ; -------------------------------------------------------
    USING MACRO arglist:VARARG                      ;; Must be placed before dynamic code
      MLOCAL r64@@_@@[argcount(arglist)] :QWORD
      reg_64_bit_list_@@@@ equ arglist
    ENDM

    SaveRegs MACRO                                  ;; must be placed AFTER LOCALs
      cntr = 0
      %FOR arg,<reg_64_bit_list_@@@@>
        ;; %echo arg
        mov r64@@_@@[cntr], arg
        cntr = cntr + 8
      ENDM
    ENDM

    RestoreRegs MACRO                               ;; must be placed BEFORE "ret"
      cntr = 0
      %FOR arg,<reg_64_bit_list_@@@@>
        ;; %echo arg
        mov arg, r64@@_@@[cntr]
        cntr = cntr + 8
      ENDM
    ENDM
  ; -------------------------------------------------------

    .code

; ¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤

entry_point proc

    USING r12,r13,r14,r15           ; allocate local space for registers

    SaveRegs                        ; save register list

    call tstproc

    waitkey

    RestoreRegs                     ; restore register list

    .exit

entry_point endp

; ¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤

tstproc proc

    USING rax,rbx,rcx,rdx

    SaveRegs

    nop
    nop
    nop
    nop

    RestoreRegs

    ret

tstproc endp

; ¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤

    end