Abstracted assembler

Open questions

1. What is the default data size, 32 or 64 bit?
2. How to specify SIMD and floating-point operations?
3. What is the simplest type system that will work?
4. Which instruction sets should be supported?

Language features

bit slicing

   index-index
       a = b.[10..2]
   index-count
       a = b.[10,2]
   index    
       bit = n.[index]
       

Common symbols

+ - * / 
< > <= >= <> 
& and
| or
^ eor
  bic
  orn
  eon
  not

<<  lsl
>>  lsr
>>> asr
>|> ror

Built in functions

clz    count leading zeros
cls    count leading signs
rbit   mirror bits
rev    swap endian
cnt    population count
cset   conditionally set 0 or 1
csetm  conditionally set 0 or -1

Program flow

    call
    return
    again
    exit
    bcc
    while
    dowhile
    for
       for x
       for x = 1 to y
    if then else
    

Conditional

   a = cond ? val1 : val2
   b = <eq> ? x+1 : y
       (eq)
       |eq|
       <a+b:cs>
   a = b + c

Memory access

   [addr].32 = 0
   b = [addr].s16
   b = [addr1 + addr2].s16
   arr[idx].64 = [addr2]
   arr[idx]!64 = [addr2]     Increment idx by 8

Data structures

String
Array
BitArray
List
Hastable
Set
Tree

Examples

Print value in hexadecimal

toHexStringNLZ:
   clz     x11,x0
   sub     x11,x11,#64
   subs    x1,x1,x11,asr #2
   cinc    x1,x1,eq
   strb    wzr,[x1]
.loop:
   ubfx    x10,x0,#0,#4
   cmp     x10,#9
   add     x10,x10,#'0'
   add     x11,x10,#7
   csel    x11,x10,x11,ls
   strb    w11,[x1,#-1]!
   lsr     x0,x0,#4
   cbne    x0,.loop
   ret

tohhex adr number
   leadingZeros = clz number
   remainingBits = 64 - leadingZeros
   remainingDigits = remainingBits / 4
   adr = adr + remainingDigits

   if remainingDigits = 0
       adr += 1
   [adr].8 = 0
    
   dowhile number <> 0
       digit = number.[3..0]
       number = number >> 4

       if digit <= 9
           digit = digit + '0'
       else
           digit = digit + '0' + 7  

           adr -= 1
           [adr].8 = digit