How to declare a define in ARM assembly and use it?

Question

I am trying to work with icachetest and it has a file in it named icache.s contains:

#define LOOP \
        subs    r2, r2, #1             ; \ 
        mov     r0, r0                 ; \
        mov     r0, r0                 ; \ 
        mov     r0, r0                 ; \
        mov     r0, r0                 ; \
        mov     r0, r0                 ; \
        beq     end_loop               ; \
        mov     r0, r0                 ; \

I am using arm-eabi-as to compile this project but I get this error:

  AS     icache.S
icache.S: Assembler messages:
icache.S:16: Error: junk at end of line, first unrecognized character is `\'
icache.S:17: Error: junk at end of line, first unrecognized character is `\'
icache.S:18: Error: junk at end of line, first unrecognized character is `\'
icache.S:19: Error: junk at end of line, first unrecognized character is `\'
icache.S:20: Error: junk at end of line, first unrecognized character is `\'
icache.S:21: Error: junk at end of line, first unrecognized character is `\'
icache.S:22: Error: junk at end of line, first unrecognized character is `\'
icache.S:23: Error: junk at end of line, first unrecognized character is `\'
icache.S:52: Error: bad instruction `loop LOOP LOOP LOOP LOOP LOOP LOOP LOOP LOOP LOOP LOOP LOOP LOOP LOOP LOOP LOOP'
icache.S:53: Error: bad instruction `loop LOOP LOOP LOOP LOOP LOOP LOOP LOOP LOOP LOOP LOOP LOOP LOOP LOOP LOOP LOOP'
icache.S:54: Error: bad instruction `loop LOOP LOOP LOOP LOOP LOOP LOOP LOOP LOOP LOOP LOOP LOOP LOOP LOOP LOOP LOOP'

Answer 1

The LOOP is a C macro as others have pointed out. As it has no parameters or conditionals, it is easily replaced with a gas macro.

.macro  LOOP
    subs    r2, r2, #1
    mov     r0, r0
    mov     r0, r0
    mov     r0, r0
    mov     r0, r0
    mov     r0, r0
    beq     end_loop
    mov     r0, r0
.endm

It will behave the same as a #define after this, with the caveat that only one is allowed per line. The ARM assembler does allow multiple op-codes on a line (as far as I know).

You can use .rept to repeat the macro.

.rept 2048
   LOOP
.endr