; ARM Thumb Assembler for uLisp - Version 9 - 6th August 2024 ; see http://www.ulisp.com/show?2YRU ; ; Extract register number (defun regno (sym) (case sym (sp 13) (lr 14) (pc 15) (t (read-from-string (subseq (string sym) 1))))) ; Pack arguments into bit fields (defun emit (bits &rest args) (let ((word 0) (shift -28)) (mapc #'(lambda (value) (let ((width (logand (ash bits shift) #xf))) (incf shift 4) (unless (zerop (ash value (- width))) (error "Won't fit")) (setq word (logior (ash word width) value)))) args) word)) (defun offset (label) (ash (- label *pc* 4) -1)) ; data (defun $word (val) (append (unless (zerop (mod *pc* 4)) (list ($nop))) (list (logand val #xffff) (logand (ash val -16) #xffff)))) ; Shared routines, ordered by first four bits ; lsl lsr 0 (defun lsl-lsr-0 (op immed5 argm argd) (emit #x41533000 0 op immed5 (regno argm) (regno argd))) ; asr 0 (defun asr-0 (op immed5 argm argd) (emit #x41533000 1 op immed5 (regno argm) (regno argd))) ; add sub 1 (defun add-sub-1 (op argd argn argm) (cond ((numberp argm) (emit #x61333000 #b000111 op argm (regno argn) (regno argd))) ((null argm) (emit #x61333000 #b000110 op (regno argn) (regno argd) (regno argd))) (t (emit #x61333000 #b000110 op (regno argm) (regno argn) (regno argd))))) ; mov sub 2 3 (defun mov-sub-2-3 (op2 op argd immed8) (emit #x41380000 op2 op (regno argd) immed8)) ; add mov 4 (defun add-mov-4 (op argd argm) (let ((rd (regno argd)) (rm (regno argm))) (cond ((and (>= rd 8) (>= rm 8)) (emit #x61333000 #b010001 op #b011 (- rm 8) (- rd 8))) ((>= rm 8) (emit #x61333000 #b010001 op #b001 (- rm 8) rd)) ((>= rd 8) (emit #x61333000 #b010001 op #b010 rm (- rd 8)))))) ; reg-reg (defun reg-reg (op argd argm) (emit #xa3300000 op (regno argm) (regno argd))) ; bx blx 4 (defun bx-blx (op argm) (emit #x81430000 #b01000111 op (regno argm) 0)) ; str ldr 4, 6, 9 (defun str-ldr (op argd arg2) (cond ((numberp arg2) (when (= op 0) (error "str not allowed with label")) (let ((arg (- (truncate (+ arg2 2) 4) (truncate *pc* 4) 1))) (emit #x41380000 4 1 (regno argd) (max 0 arg)))) ((listp arg2) (let ((argn (first arg2)) (immed (or (eval (second arg2)) 0))) (unless (zerop (mod immed 4)) (error "not multiple of 4")) (cond ((eq (regno argn) 15) (when (= op 0) (error "str not allowed with pc")) (emit #x41380000 4 1 (regno argd) (truncate immed 4))) ((eq (regno argn) 13) (emit #x41380000 9 op (regno argd) (truncate immed 4))) (t (emit #x41533000 6 op (truncate immed 4) (regno argn) (regno argd)))))) (t (error "illegal argument")))) (defun str-ldr-5 (op argd arg2) (cond ((listp arg2) (let ((argn (first arg2)) (argm (second arg2))) (emit #x43333000 5 op (regno argm) (regno argn) (regno argd)))) (t (error "illegal argument")))) ; add-10 (defun add-10 (op argd immed8) (emit #x41380000 #b1010 op (regno argd) (truncate immed8 4))) ; add-sub-11 (defun add-sub-11 (op immed7) (emit #x81700000 #b11010000 op (truncate immed7 4))) ; push pop 11 (defun push-pop (op lst) (let ((byte 0) (r 0)) (mapc #'(lambda (x) (cond ((and (= op 0) (eq x 'lr)) (setq r 1)) ((and (= op 1) (eq x 'pc)) (setq r 1)) (t (setq byte (logior byte (ash 1 (regno x))))))) lst) (emit #x41218000 11 op 2 r byte))) ; b cond 13 (defun b-cond-13 (cnd label) (let ((soff8 (logand (offset label) #xff))) (emit #x44800000 13 cnd soff8))) (defun cpside (op aif) (emit #xb1130000 #b10110110011 op 0 aif)) ; Alphabetical list of mnemonics (defun $adc (argd argm) (reg-reg #b0100000101 argd argm)) (defun $add (argd argn &optional argm) (cond ((numberp argm) (cond ((eq (regno argn) 15) (add-10 0 argd argm)) ((eq (regno argn) 13) (add-10 1 argd argm)) (t (add-sub-1 0 argd argn argm)))) ((and (numberp argn) (null argm)) (cond ((eq (regno argd) 13) (add-sub-11 0 argn)) (t (mov-sub-2-3 3 0 argd argn)))) (t (cond ((or (>= (regno argd) 8) (>= (regno argn) 8)) (add-mov-4 0 argd argn)) (t (add-sub-1 0 argd argn argm)))))) (defun $and (argd argm) (reg-reg #b0100000000 argd argm)) (defun $asr (argd argm &optional arg2) (cond ((numberp arg2) (asr-0 0 arg2 argm argd)) ((numberp argm) (asr-0 0 argm argd argd)) (t (reg-reg #b0100000100 argd argm)))) (defun $b (label) (emit #x41b00000 #xe 0 (logand (offset label) #x7ff))) (defun $bcc (label) (b-cond-13 3 label)) (defun $bcs (label) (b-cond-13 2 label)) (defun $beq (label) (b-cond-13 0 label)) (defun $bge (label) (b-cond-13 10 label)) (defun $bgt (label) (b-cond-13 12 label)) (defun $bhi (label) (b-cond-13 8 label)) (defun $bhs (label) (b-cond-13 2 label)) (defun $ble (label) (b-cond-13 13 label)) (defun $blo (label) (b-cond-13 3 label)) (defun $blt (label) (b-cond-13 11 label)) (defun $bmi (label) (b-cond-13 4 label)) (defun $bne (label) (b-cond-13 1 label)) (defun $bpl (label) (b-cond-13 5 label)) (defun $bic (argd argm) (reg-reg #b0100001110 argd argm)) (defun $bl (label) (list (emit #x5b000000 #b11110 (logand (ash (offset label) -11) #x7ff)) (emit #x5b000000 #b11111 (logand (offset label) #x7ff)))) (defun $blx (argm) (bx-blx 1 argm)) (defun $bx (argm) (bx-blx 0 argm)) (defun $cmn (argd argm) (reg-reg #b0100001011 argd argm)) (defun $cmp (argd argm) (cond ((numberp argm) (mov-sub-2-3 2 1 argd argm)) (t (reg-reg #b0100001010 argd argm)))) (defun $cpsid (aif) (cpside 1 aif)) (defun $cpsie (aif) (cpside 0 aif)) (defun $eor (argd argm) (reg-reg #b0100000001 argd argm)) (defun $ldr (argd arg2) (str-ldr 1 argd arg2)) (defun $ldrb (argd arg2) (str-ldr-5 6 argd arg2)) (defun $ldrh (argd arg2) (str-ldr-5 5 argd arg2)) (defun $ldrsb (argd arg2) (str-ldr-5 3 argd arg2)) (defun $ldrsh (argd arg2) (str-ldr-5 7 argd arg2)) (defun $lsl (argd argm &optional arg2) (cond ((numberp arg2) (lsl-lsr-0 0 arg2 argm argd)) ((numberp argm) (lsl-lsr-0 0 argm argd argd)) (t (reg-reg #b0100000010 argd argm)))) (defun $lsr (argd argm &optional arg2) (cond ((numberp arg2) (lsl-lsr-0 1 arg2 argm argd)) ((numberp argm) (lsl-lsr-0 1 argm argd argd)) (t (reg-reg #b0100000011 argd argm)))) (defun $mov (argd argm) (cond ((numberp argm) (mov-sub-2-3 2 0 argd argm)) ((or (>= (regno argd) 8) (>= (regno argm) 8)) (add-mov-4 1 argd argm)) (t ; Synonym of LSLS Rd, Rm, #0 (lsl-lsr-0 0 0 argm argd)))) (defun $mul (argd argm) (reg-reg #b0100001101 argd argm)) (defun $mvn (argd argm) (reg-reg #b0100001111 argd argm)) (defun $neg (argd argm) (reg-reg #b0100001001 argd argm)) (defun $nop () ; mov r8,r8 (add-mov-4 1 'r8 'r8)) (defun $orr (argd argm) (reg-reg #b0100001100 argd argm)) (defun $push (lst) (push-pop 0 lst)) (defun $pop (lst) (push-pop 1 lst)) (defun $rev (argd argm) (reg-reg #b1011101000 argd argm)) (defun $rev16 (argd argm) (reg-reg #b1011101001 argd argm)) (defun $revsh (argd argm) (reg-reg #b1011101010 argd argm)) (defun $ror (argd argm) (reg-reg #b0100000111 argd argm)) (defun $sbc (argd argm) (reg-reg #b0100000110 argd argm)) (defun $str (argd arg2) (str-ldr 0 argd arg2)) (defun $strb (argd arg2) (str-ldr-5 2 argd arg2)) (defun $sub (argd argn &optional argm) (cond ((not (numberp argn)) (add-sub-1 1 argd argn argm)) ((eq (regno argd) 13) (add-sub-11 1 argn)) (t (mov-sub-2-3 3 1 argd argn)))) (defun $sxtb (argd argm) (reg-reg #b1011001001 argd argm)) (defun $sxth (argd argm) (reg-reg #b1011001000 argd argm)) (defun $tst (argd argm) (reg-reg #b0100001000 argd argm)) (defun $uxtb (argd argm) (reg-reg #b1011001011 argd argm)) (defun $uxth (argd argm) (reg-reg #b1011001010 argd argm))