;; BEGIN BOOTSTRAP

@use ext_std:*

@let sp              RH
@let vector_table    0x10
@let vt_ISR0         0x10 ; ISR0
@let vt_ISR1         0x11 ; ISR1
@let vt_ISR2         0x12 ; ISR2
@let vt_ISR3         0x13 ; ISR3
@let vt_stack_addr   0x14 ; Stack address
@let vt_term_pp_addr 0x15 ; Terminal peripheral address
@let vt_kb_pp_addr   0x16 ; Keyboard peripheral address
@let vt_gr_mode_addr 0x17 ; Graphics mode setting address
@let vt_sprite_mem   0x18 ; Sprite memory address
@let vt_text_mem     0x19 ; Text memory buffer address

@let stack_segment   0x8000
@let mmio_segment    0xE000
@let terminal_addr   0xE000
@let keyboard_addr   0xE001
@let gr_mode_addr    0xE002
@let sprite_mem      0xE800
@let text_mem        0xF800

@let gr_disabled_mode 0b00
@let gr_text_mode     0b01
@let gr_sprite_mode   0b10

@address 0x0
  ldi vt_stack_addr RA
  ldr RA SP
  jpi program_segment

@address vector_table
  keyboard_isr   ; 0x10
  hlt_isr        ; 0x11
  hlt_isr        ; 0x12
  hlt_isr        ; 0x13
  stack_segment  ; 0x14
  terminal_addr  ; 0x15
  keyboard_addr  ; 0x16
  gr_mode_addr   ; 0x17
  sprite_mem     ; 0x18
  text_mem       ; 0x19

@label hlt_isr
  ldi 0x55 RE
  hlt

@label keyboard_isr
  spu RA
  spu RB
  ldi vt_kb_pp_addr RA
  ldr RA RA
  ldr RA RA
  ldi vt_term_pp_addr RB
  ldr RB RB
  str RA RB
  spo RB
  spo RA
  rti

@label program_segment
  ldi vt_gr_mode_addr RA
  ldr RA RA
  ldi gr_disabled_mode RB
  str RB RA

  jpi main

;; END BOOTSTRAP

@label text_mode
  1
@label graphics_mode_addr_p
  23
@label text_mem_addr_p
  25
@label int_1
  65
@label int_5
  26

; <ast.FunctionDef object at 0x1048ce500>
@label nth_letter
; stack frame with offsets
; return_address_0 3
; n 4
; <ast.Return object at 0x1048ce440>
; <ast.Add object at 0x1045f6ad0>
; BinOp lhs <ast.BinOp object at 0x1048ce410>
; <ast.Name object at 0x1048ce3e0> (n)
  ldi vt_stack_addr RA
  ldr RA RA
  ldi 4 RB
  add RA RB RA
  ldr RA RA
  spu RA
; BinOp rhs <ast.BinOp object at 0x1048ce410>
; <ast.Constant object at 0x1048ce3b0>
  ldi int_1 RA
  ldr RA RA
  spu RA
  spo RB
  spo RA
  add RA RB RA
  spu RA
  ldi vt_stack_addr RA
  ldr RA RA
  ldi 3 RB
  add RA RB RA
; stack address of return address is stored in reg RA
  spo RB
; return value is stored in reg RB
  mov RA SP
  ldr RA RA
  spu RB
; return from function
  jpr RA

@label main
; stack frame with offsets
; graphics_mode_addr 0
; text_mem_addr 1
; i 2
  addi SP 3 SP
; <ast.Assign object at 0x1048ce860>
; assigning graphics_mode_addr at stack segment + 0
; evaluating value to be assigned
; <ast.Call object at 0x1048ce800>
; Builtin call load [<ast.Name object at 0x1048ce770>]
; <ast.Name object at 0x1048ce770> (GRAPHICS_MODE_ADDR_P)
  ldi graphics_mode_addr_p RC
  ldr RC RC
  spu RC
  spo RC
  ldr RC RC
  spu RC
; assigning value to stack segment + 0
  ldi vt_stack_addr RA
  ldr RA RA
  ldi 0 RB
  add RA RB RA
  spo RB
  str RB RA
; <ast.Assign object at 0x1048ce740>
; assigning text_mem_addr at stack segment + 1
; evaluating value to be assigned
; <ast.Call object at 0x1048ce6e0>
; Builtin call load [<ast.Name object at 0x1048ce650>]
; <ast.Name object at 0x1048ce650> (TEXT_MEM_ADDR_P)
  ldi text_mem_addr_p RC
  ldr RC RC
  spu RC
  spo RC
  ldr RC RC
  spu RC
; assigning value to stack segment + 1
  ldi vt_stack_addr RA
  ldr RA RA
  ldi 1 RB
  add RA RB RA
  spo RB
  str RB RA
; <ast.Call object at 0x1048ce5f0>
; Builtin call store [<ast.Name object at 0x1048ce560>, <ast.Name object at 0x1048ce530>]
; <ast.Name object at 0x1048ce560> (graphics_mode_addr)
  ldi vt_stack_addr RA
  ldr RA RA
  ldi 0 RB
  add RA RB RA
  ldr RA RA
  spu RA
; <ast.Name object at 0x1048ce530> (TEXT_MODE)
  ldi text_mode RA
  ldr RA RA
  spu RA
  spo RB
  spo RA
  str RB RA
; <ast.Assign object at 0x1048ce350>
; assigning i at stack segment + 2
; evaluating value to be assigned
; <ast.Constant object at 0x1048ce2f0>
  ldi 0 RC
  spu RC
; assigning value to stack segment + 2
  ldi vt_stack_addr RA
  ldr RA RA
  ldi 2 RB
  add RA RB RA
  spo RB
  str RB RA
; <ast.Call object at 0x1048ce290>
; Builtin call asm [<ast.Constant object at 0x1048ce200>]
  ldi 0b111111111 RG
; <ast.While object at 0x1048ce1d0>
@label while_test_2
; <ast.Name object at 0x1048ce170> (i)
  ldi vt_stack_addr RB
  ldr RB RB
  ldi 2 RC
  add RB RC RB
  ldr RB RB
  spu RB
; <ast.Constant object at 0x1048ce140>
  ldi int_5 RB
  ldr RB RB
  spu RB
  spo RC
  spo RB
  sub RB RC RB
  bri carry Compare_true_6
  ldi 0 RB
  spu RB
  jpi Compare_end_7
@label compare_true_6
  ldi 1 RB
  spu RB
@label compare_end_7
  spo RA
  addi RA 0 RA
  bri zero While_else_3
; <ast.Call object at 0x1048ce0e0>
; Builtin call store [<ast.BinOp object at 0x1048ce050>, <ast.Call object at 0x1048cdd80>]
; <ast.Add object at 0x1045f6ad0>
; BinOp lhs <ast.BinOp object at 0x1048ce050>
; <ast.Name object at 0x1048ce020> (text_mem_addr)
  ldi vt_stack_addr RA
  ldr RA RA
  ldi 1 RB
  add RA RB RA
  ldr RA RA
  spu RA
; BinOp rhs <ast.BinOp object at 0x1048ce050>
; <ast.Name object at 0x1048cdff0> (i)
  ldi vt_stack_addr RA
  ldr RA RA
  ldi 2 RB
  add RA RB RA
  ldr RA RA
  spu RA
  spo RB
  spo RA
  add RA RB RA
  spu RA
; <ast.Call object at 0x1048cdd80>
; Call function nth_letter
  ldi 0 RA
  spu RA
; <ast.Name object at 0x1048cdd20> (i)
  ldi vt_stack_addr RA
  ldr RA RA
  ldi 2 RB
  add RA RB RA
  ldr RA RA
  spu RA
; set up return address and jump to subroutine
  subi SP 2 RA
  lpc RB
  addi RB 3 RB
  str RB RA
  jpi nth_letter
  spo RB
  spo RA
  str RB RA
; <ast.Assign object at 0x1048ccc70>
; assigning i at stack segment + 2
; evaluating value to be assigned
; <ast.Add object at 0x1045f6ad0>
; BinOp lhs <ast.BinOp object at 0x1048cda50>
; <ast.Name object at 0x1048cd750> (i)
  ldi vt_stack_addr RC
  ldr RC RC
  ldi 2 RD
  add RC RD RC
  ldr RC RC
  spu RC
; BinOp rhs <ast.BinOp object at 0x1048cda50>
; <ast.Constant object at 0x1048cd720>
  ldi 1 RC
  spu RC
  spo RD
  spo RC
  add RC RD RC
  spu RC
; assigning value to stack segment + 2
  ldi vt_stack_addr RA
  ldr RA RA
  ldi 2 RB
  add RA RB RA
  spo RB
  str RB RA
  jpi While_test_2
@label while_else_3
@label while_end_4
; <ast.While object at 0x1048cd0f0>
@label while_test_8
; <ast.Constant object at 0x1048cd060>
  ldi 1 RB
  spu RB
  spo RA
  addi RA 0 RA
  bri zero While_else_9
; <ast.Pass object at 0x1048ccfa0>
  jpi While_test_8
@label while_else_9
@label while_end_10
  subi SP 3 SP