(declaim (optimize (speed 3) (space 0) (safety 0) (debug 0) (compilation-speed 0)))

(defconstant data '(1 2 3))

(defun solution ()
  (let ((acc '(0)))
    (loop
      (dolist (n data)
        (declare (type integer n))
        (let ((new-freq (+ n (the integer (car acc)))))
          (declare (type integer new-freq))
          (if (find new-freq acc)
              (return-from solution new-freq)
              (push new-freq acc)))))))

; disassembly for SOLUTION
; Size: 197 bytes. Origin: #x52D1C7B7
; 7B7:       4C8B0DB2FFFFFF   MOV R9, [RIP-78]                ; no-arg-parsing entry point
                                                              ; '(0)
; 7BE:       6690             NOP
; 7C0: L0:   4C8B15B1FFFFFF   MOV R10, [RIP-79]               ; '(1 2 3)
; 7C7:       E981000000       JMP L7
; 7CC:       0F1F4000         NOP
; 7D0: L1:   498B52F9         MOV RDX, [R10-7]
; 7D4:       498B4201         MOV RAX, [R10+1]
; 7D8:       4C8BD0           MOV R10, RAX
; 7DB:       4C894DF8         MOV [RBP-8], R9
; 7DF:       4C8955F0         MOV [RBP-16], R10
; 7E3:       498B79F9         MOV RDI, [R9-7]
; 7E7:       FF1425A8001052   CALL QWORD PTR [#x521000A8]     ; GENERIC-+
; 7EE:       488BF2           MOV RSI, RDX
; 7F1:       4C8B55F0         MOV R10, [RBP-16]
; 7F5:       4C8B4DF8         MOV R9, [RBP-8]
; 7F9:       498BD9           MOV RBX, R9
; 7FC:       EB19             JMP L3
; 7FE:       6690             NOP
; 800: L2:   4C8B43F9         MOV R8, [RBX-7]
; 804:       488BD6           MOV RDX, RSI
; 807:       498BF8           MOV RDI, R8
; 80A:       FF1425F0001052   CALL QWORD PTR [#x521000F0]     ; %EQL/INTEGER
; 811:       744C             JEQ L8
; 813:       488B5B01         MOV RBX, [RBX+1]
; 817: L3:   4881FB17001050   CMP RBX, #x50100017             ; NIL
; 81E:       75E0             JNE L2
; 820: L4:   49896D40         MOV [R13+64], RBP               ; thread.pseudo-atomic-bits
; 824:       4D8B5D20         MOV R11, [R13+32]               ; thread.alloc-region
; 828:       498D4310         LEA RAX, [R11+16]
; 82C:       493B4528         CMP RAX, [R13+40]
; 830:       773F             JNBE L9
; 832:       49894520         MOV [R13+32], RAX               ; thread.alloc-region
; 836: L5:   498D4307         LEA RAX, [R11+7]
; 83A:       49316D40         XOR [R13+64], RBP               ; thread.pseudo-atomic-bits
; 83E:       7402             JEQ L6
; 840:       CC09             BREAK 9                         ; pending interrupt trap
; 842: L6:   488970F9         MOV [RAX-7], RSI
; 846:       4C894801         MOV [RAX+1], R9
; 84A:       4C8BC8           MOV R9, RAX
; 84D: L7:   4981FA17001050   CMP R10, #x50100017             ; NIL
; 854:       0F8466FFFFFF     JEQ L0
; 85A:       E971FFFFFF       JMP L1
; 85F: L8:   4981F817001050   CMP R8, #x50100017              ; NIL
; 866:       74B8             JEQ L4
; 868:       488BD6           MOV RDX, RSI
; 86B:       488BE5           MOV RSP, RBP
; 86E:       F8               CLC
; 86F:       5D               POP RBP
; 870:       C3               RET
; 871: L9:   6A10             PUSH 16
; 873:       FF142528001052   CALL QWORD PTR [#x52100028]     ; ALLOC-TRAMP-R11
; 87A:       EBBA             JMP L5