Adapt the code to play well with nasm's asan

The address sanitizer from nasm provides quite a few goodies, so let's
adapt the code more to it to benefit from those.

Signed-off-by: Miquel Sabaté Solà <mssola@mssola.com>

13 files changed, 145 insertions, 144 deletions

diff --git a/include/apu.s b/include/apu.s
index 65d9876..bb0319f 100644
--- a/include/apu.s
+++ b/include/apu.s
@@ -1,4 +1,4 @@
 .scope APU
-    DMC           = $4010
-    FRAME_COUNTER = $4017
+    m_dmc           = $4010
+    m_frame_counter = $4017
 .endscope
diff --git a/include/globals.s b/include/globals.s
index 842de34..f9777e5 100644
--- a/include/globals.s
+++ b/include/globals.s
@@ -6,17 +6,17 @@
     ;; Argument values reserved passing arguments to functions in memory.
     zp_arg0 = $00
     zp_arg1 = $01
-    zp_arg2 = $02
-    zp_arg3 = $03
-    zp_arg4 = $04
+    ;; zp_arg2 = $02
+    ;; zp_arg3 = $03
+    ;; zp_arg4 = $04
 
     ;;;
     ;; Random values that can be used inside of functions for temporary values
     ;; so `zp_argX` variables are not overwritten as often.
     zp_tmp0 = $05
     zp_tmp1 = $06
-    zp_tmp2 = $07
-    zp_tmp3 = $08
+    ;; zp_tmp2 = $07
+    ;; zp_tmp3 = $08
 
     ;;;
     ;; Reserve a byte of memory for preserving indices on memory. This is needed
diff --git a/include/joypad.s b/include/joypad.s
index 141877f..f7268e8 100644
--- a/include/joypad.s
+++ b/include/joypad.s
@@ -10,8 +10,8 @@
     BUTTON_RIGHT  = 1 << 0
 
     ;; Port addresses for controllers.
-    JOYPAD1 = $4016
-    JOYPAD2 = $4017
+    m_joypad1 = $4016
+    ;; m_joypad2 = $4017
 
     ;; After running a `read_*` function these two variables will contain the
     ;; given result.
@@ -49,14 +49,14 @@
     .proc unsafe_read_x
         ;; Start the latch process.
         lda #$01
-        sta Joypad::JOYPAD1
+        sta Joypad::m_joypad1
         sta Joypad::zp_buttons1, x   ; Bit as a guard for the loop below.
         lsr
-        sta Joypad::JOYPAD1
+        sta Joypad::m_joypad1
 
         ;; Now the joypad is ready to accept reads.
     @loop:
-        lda Joypad::JOYPAD1, x
+        lda Joypad::m_joypad1, x
         and #%00000011              ; Ignore bits other than controller.
         cmp #$01                    ; Set carry if and only if nonzero.
         rol Joypad::zp_buttons1, x   ; Carry -> bit 0; bit 7 -> Carry
diff --git a/include/oam.s b/include/oam.s
index 22935b2..a73494d 100644
--- a/include/oam.s
+++ b/include/oam.s
@@ -1,11 +1,12 @@
 .scope OAM
-    ADDRESS = $2003
-    DMA     = $4014
-.endscope
+    ;; Region in internal RAM where sprites are being allocated for later use in
+    ;; the DMA process. The entire page is reserved, as there are 64 sprites x 4
+    ;; bytes each = 256 bytes in total.
+    m_sprites = $200            ; asan:reserve $100
+
+    ;;;
+    ;; Actual addresses from OAM space.
 
-.macro OAM_WRITE_SPRITES
-    lda #$00
-    sta OAM::ADDR
-    lda #$02
-    sta OAM::DMA
-.endmacro
+    m_address = $2003
+    m_dma     = $4014
+.endscope
diff --git a/include/ppu.s b/include/ppu.s
index a9c0ed2..7882809 100644
--- a/include/ppu.s
+++ b/include/ppu.s
@@ -1,10 +1,10 @@
 .scope PPU
-    CONTROL = $2000
-    MASK    = $2001
-    STATUS  = $2002
-    SCROLL  = $2005
-    ADDRESS = $2006
-    DATA    = $2007
+    m_control = $2000
+    m_mask    = $2001
+    m_status  = $2002
+    m_scroll  = $2005
+    m_address = $2006
+    m_data    = $2007
 
     ;; Shadow for the PPU::CONTROL value. Touch this value instead of accessing
     ;; the PPU register directly.
diff --git a/src/assets.s b/src/assets.s
index 3d1a6a3..82b6a06 100644
--- a/src/assets.s
+++ b/src/assets.s
@@ -24,7 +24,7 @@
         lda #.hibyte(main_screen)
         sta Globals::zp_arg1
         ldx #$28
-        jsr load_screen_x
+        jsr load_screen_x ;; TODO: jal
 
         rts
     .endproc
@@ -33,17 +33,17 @@
     ;; Globals::zp_arg{0,1}. Set the `x` register to the high byte of the
     ;; nametable to be used.
     .proc load_screen_x
-        bit PPU::STATUS
+        bit PPU::m_status
 
-        stx PPU::ADDRESS
+        stx PPU::m_address
         lda #$00
-        sta PPU::ADDRESS
+        sta PPU::m_address
 
         ldy #0
         ldx #4
     @loop:
         lda (Globals::zp_arg0), y
-        sta PPU::DATA
+        sta PPU::m_data
         iny
         bne @loop
 
@@ -60,44 +60,44 @@
     ;; Performs all the needed tricks in order to get the first nametable as
     ;; expected.
     .proc prepare_for_title_screen
-        bit PPU::STATUS
+        bit PPU::m_status
 
         lda #$23
-        sta $2006
+        sta PPU::m_address
         lda #$C8
-        sta $2006
+        sta PPU::m_address
 
         ldx #$10
     @upper_title_bar_loop:
         lda #%10101010
-        sta $2007
+        sta PPU::m_data
         dex
         bne @upper_title_bar_loop
 
         ;; Update 2nd palette for background. This is redundant upon entering
         ;; the game, but it makes sense after a game over.
         lda #$3F
-        sta PPU::ADDRESS
+        sta PPU::m_address
         lda #$09
-        sta PPU::ADDRESS
+        sta PPU::m_address
         lda #$28
-        sta PPU::DATA
+        sta PPU::m_data
         lda #$2C
-        sta PPU::DATA
+        sta PPU::m_data
         lda #$16
-        sta PPU::DATA
+        sta PPU::m_data
 
         ;; Update 1st palette for foreground.
         lda #$3F
-        sta PPU::ADDRESS
+        sta PPU::m_address
         lda #$11
-        sta PPU::ADDRESS
+        sta PPU::m_address
         lda #$30
-        sta PPU::DATA
+        sta PPU::m_data
         lda #$10
-        sta PPU::DATA
+        sta PPU::m_data
         lda #$30
-        sta PPU::DATA
+        sta PPU::m_data
 
         rts
     .endproc
@@ -105,31 +105,31 @@
     ;; Performs all the needed tricks in order to get the second nametable as
     ;; expected.
     .proc prepare_for_main_screen
-        bit PPU::STATUS
+        bit PPU::m_status
 
         ;; Update 2nd palette for background.
         lda #$3F
-        sta PPU::ADDRESS
+        sta PPU::m_address
         lda #$09
-        sta PPU::ADDRESS
+        sta PPU::m_address
         lda #$14
-        sta PPU::DATA
+        sta PPU::m_data
         lda #$2C
-        sta PPU::DATA
+        sta PPU::m_data
         lda #$28
-        sta PPU::DATA
+        sta PPU::m_data
 
         ;; Update 1st palette for foreground.
         lda #$3F
-        sta PPU::ADDRESS
+        sta PPU::m_address
         lda #$11
-        sta PPU::ADDRESS
+        sta PPU::m_address
         lda #$16
-        sta PPU::DATA
+        sta PPU::m_data
         lda #$10
-        sta PPU::DATA
+        sta PPU::m_data
         lda #$30
-        sta PPU::DATA
+        sta PPU::m_data
 
         rts
     .endproc
@@ -137,14 +137,14 @@
     ;; Copies all the palettes for our game into the proper PPU address.
     .proc init_palettes
         lda #$3F
-        sta PPU::ADDRESS
+        sta PPU::m_address
         lda #$00
-        sta PPU::ADDRESS
+        sta PPU::m_address
 
         ldx #0
     @load_palettes_loop:
         lda palettes, x
-        sta PPU::DATA
+        sta PPU::m_data
         inx
         cpx #$20
         bne @load_palettes_loop
@@ -177,9 +177,9 @@
     ;; simple game, I have so much space left in the cartridge that I can go
     ;; bananas with it. This helps out loading the screen as we can go faster
     ;; and it is less error prone.
-    title_screen:   
+    title_screen:
         .incbin "../assets/title.nam"
-    main_screen:   
+    main_screen:
         .incbin "../assets/main.nam"
 .endscope
 
diff --git a/src/bullets.s b/src/bullets.s
index db8bfd7..0f31d0c 100644
--- a/src/bullets.s
+++ b/src/bullets.s
@@ -18,7 +18,7 @@
     ;;                    bullet.
     ;;  2. Y coordinate.
     ;;  3. X coordinate.
-    zp_bullets_pool_base = $A0
+    zp_bullets_pool_base = $A0  ; asan:reserve $1E
 
     ;; The current amount of bullets on screen.
     zp_bullets_pool_size = $E0
diff --git a/src/driver.s b/src/driver.s
index 3ed0536..149eaa7 100644
--- a/src/driver.s
+++ b/src/driver.s
@@ -6,7 +6,7 @@
     ;;
     ;; NOTE: this memory address is shared with `zp_title_timer`, as they can
     ;; never conflict with each other.
-    zp_player_timer = $30
+    zp_player_timer = $30       ; asan:ignore
     PLAYER_TIMER_VALUE = HZ * 2
 
     .ifdef PAL
@@ -165,7 +165,7 @@
 
         ;; It is a valid bullet! Set it now.
         lda Bullets::zp_bullets_pool_base + 1, x
-        sta $200, y
+        sta OAM::m_sprites, y
         iny
 
         ;; The tile selection depends on how many moves the bullet has done.
@@ -183,14 +183,14 @@
     @last_bullet_tile:
         lda #$1E
     @set_bullet_tile:
-        sta $200, y
+        sta OAM::m_sprites, y
 
         iny
         lda #0
-        sta $200, y
+        sta OAM::m_sprites, y
         iny
         lda Bullets::zp_bullets_pool_base + 2, x
-        sta $200, y
+        sta OAM::m_sprites, y
         iny
 
     @after_first_bullet:
@@ -238,7 +238,7 @@
         beq @next_bullet
 
         lda Bullets::zp_bullets_pool_base + 1, x
-        sta $200, y
+        sta OAM::m_sprites, y
         iny
 
         ;; The tile selection depends on how many moves the bullet has done.
@@ -256,14 +256,14 @@
     @other_last_bullet_tile:
         lda #$1E
     @other_set_bullet_tile:
-        sta $200, y
+        sta OAM::m_sprites, y
 
         iny
         lda #0
-        sta $200, y
+        sta OAM::m_sprites, y
         iny
         lda Bullets::zp_bullets_pool_base + 2, x
-        sta $200, y
+        sta OAM::m_sprites, y
         iny
 
     @next_bullet:
@@ -287,7 +287,7 @@
         ;; need for the 'y' register to wrap around in order to quit.
         lda #$EF
     @reset_sprite:
-        sta $200, y
+        sta OAM::m_sprites, y
         iny
         iny
         iny
diff --git a/src/enemies.s b/src/enemies.s
index 377a9a5..dbd0e08 100644
--- a/src/enemies.s
+++ b/src/enemies.s
@@ -10,7 +10,7 @@
     ENEMIES_INITIAL_X = $F0
 
     ;; TODO: 3 bytes a la bullets
-    zp_enemies_pool_base = $60
+    zp_enemies_pool_base = $60  ; asan:reserve $09
 
     zp_enemies_timer = $D0
     zp_enemies_pool_size = $D1
diff --git a/src/jetpac.s b/src/jetpac.s
index 6708ed3..6e74d53 100644
--- a/src/jetpac.s
+++ b/src/jetpac.s
@@ -50,7 +50,7 @@
 .proc main
     ;; Disable the PPU and zero out variables which shadow PPU registers.
     lda #0
-    sta PPU::MASK
+    sta PPU::m_mask
     sta PPU::zp_mask
     sta PPU::zp_control
 
@@ -89,13 +89,13 @@
         jsr Driver::switch
 
         lda PPU::zp_control
-        sta PPU::CONTROL
+        sta PPU::m_control
     .else
         jsr Title::init
 
         lda #%10001000
         sta PPU::zp_control
-        sta PPU::CONTROL
+        sta PPU::m_control
     .endif
 
     cli
@@ -103,7 +103,7 @@
     ;; Enable back the PPU
     lda #%00011110
     sta PPU::zp_mask
-    sta PPU::MASK
+    sta PPU::m_mask
 
 @main_game_loop:
     READ_JOYPAD1
diff --git a/src/player.s b/src/player.s
index c7b65af..2a87b85 100644
--- a/src/player.s
+++ b/src/player.s
@@ -7,9 +7,9 @@
 .macro FIXED_POINT_POSITION_TO_SCREEN POS_ADDR
     ;; We save the high byte into a temporary value, and we load the low byte
     ;; into the accumulator.
-    lda POS_ADDR + 1
+    lda POS_ADDR + 1            ; asan:ignore
     sta Globals::zp_tmp0
-    lda POS_ADDR
+    lda POS_ADDR                ; asan:ignore
 
     ;; And now it's a matter of rotating the high byte into the low one to
     ;; match a full byte.
@@ -73,12 +73,12 @@
     .include "../config/values/player.s"
 
     zp_screen_y          = $40
-    zp_position_y        = $41  ; NOTE: 16-bit.
+    zp_position_y        = $41  ; asan:reserve $02
     zp_target_velocity_y = $43  ; TODO: needed?
     zp_velocity_y        = $44
 
     zp_screen_x          = $45
-    zp_position_x        = $46  ; NOTE: 16-bit.
+    zp_position_x        = $46  ; asan:reserve $02
     zp_target_velocity_x = $48  ; TODO: needed?
     zp_velocity_x        = $49
 
@@ -760,40 +760,40 @@
         bvs @right
 
         lda #$01
-        sta $201
+        sta OAM::m_sprites + $01
         lda #$00
-        sta $205
+        sta OAM::m_sprites + $05
         lda #$11
-        sta $209
+        sta OAM::m_sprites + $09
         lda #$10
-        sta $20D
-        stx $211
-        sty $215
+        sta OAM::m_sprites + $0D
+        stx OAM::m_sprites + $11
+        sty OAM::m_sprites + $15
 
         ldx #%01000000
         bne @set_attributes
     @right:
         lda #$00
-        sta $201
+        sta OAM::m_sprites + $01
         lda #$01
-        sta $205
+        sta OAM::m_sprites + $05
         lda #$10
-        sta $209
+        sta OAM::m_sprites + $09
         lda #$11
-        sta $20D
-        stx $215
-        sty $211
+        sta OAM::m_sprites + $0D
+        stx OAM::m_sprites + $15
+        sty OAM::m_sprites + $11
 
         ldx #$00
 
         ;; The `x` register contains the tile attributes.
     @set_attributes:
-        stx $202
-        stx $206
-        stx $20A
-        stx $20E
-        stx $212
-        stx $216
+        stx OAM::m_sprites + $02
+        stx OAM::m_sprites + $06
+        stx OAM::m_sprites + $0A
+        stx OAM::m_sprites + $0E
+        stx OAM::m_sprites + $12
+        stx OAM::m_sprites + $16
 
         rts
     .endproc
@@ -802,27 +802,27 @@
     .proc update_sprites_coordinates
         ;; Y axis.
         lda zp_screen_y
-        sta $0200
-        sta $0204
+        sta OAM::m_sprites
+        sta OAM::m_sprites + $04
         clc
         adc #8
-        sta $0208
-        sta $020C
+        sta OAM::m_sprites + $08
+        sta OAM::m_sprites + $0C
         clc
         adc #8
-        sta $0210
-        sta $0214
+        sta OAM::m_sprites + $10
+        sta OAM::m_sprites + $14
 
         ;; X axis.
         lda zp_screen_x
-        sta $0203
-        sta $020B
-        sta $0213
+        sta OAM::m_sprites + $03
+        sta OAM::m_sprites + $0B
+        sta OAM::m_sprites + $13
         clc
         adc #8
-        sta $0207
-        sta $020F
-        sta $0217
+        sta OAM::m_sprites + $07
+        sta OAM::m_sprites + $0F
+        sta OAM::m_sprites + $17
 
         rts
     .endproc
diff --git a/src/title.s b/src/title.s
index 01d58f5..e3a2086 100644
--- a/src/title.s
+++ b/src/title.s
@@ -18,13 +18,13 @@
 
         ;; Initialize the sprite that guides the player on the menu.
         lda #SPRITE_Y_POSITION0
-        sta $200
+        sta OAM::m_sprites
         lda #$30
-        sta $201
+        sta OAM::m_sprites + 1
         lda #$00
-        sta $202
+        sta OAM::m_sprites + 2
         lda #SPRITE_X_POSITION
-        sta $203
+        sta OAM::m_sprites + 3
 
         rts
     .endproc
@@ -42,9 +42,9 @@
         beq @check_down
 
         lda #SPRITE_Y_POSITION0
-        cmp $200
+        cmp OAM::m_sprites
         beq @end
-        sta $200
+        sta OAM::m_sprites
         jmp @set_timer_and_end
 
     @check_down:
@@ -53,9 +53,9 @@
         beq @check_select
 
         lda #SPRITE_Y_POSITION1
-        cmp $200
+        cmp OAM::m_sprites
         beq @end
-        sta $200
+        sta OAM::m_sprites
         jmp @set_timer_and_end
 
     @check_select:
@@ -72,14 +72,14 @@
 
     @do_select:
         lda #SPRITE_Y_POSITION0
-        cmp $200
+        cmp OAM::m_sprites
         beq @down
-        sta $200
+        sta OAM::m_sprites
         bne @set_timer_and_end
 
     @down:
         lda #SPRITE_Y_POSITION1
-        sta $200
+        sta OAM::m_sprites
 
     @set_timer_and_end:
         lda #TIMER_INIT_VALUE
@@ -94,7 +94,7 @@
     .proc start
         ;; Hide the sprite from the menu.
         lda #$EF
-        sta $200
+        sta OAM::m_sprites
 
         lda #1
         rts
diff --git a/src/vectors.s b/src/vectors.s
index af343a7..e5d1a58 100644
--- a/src/vectors.s
+++ b/src/vectors.s
@@ -5,8 +5,8 @@
 
 ;; Debug utilities.
 .scope Debug
-    ;; Counter for frame drops.
-    zp_frame_drops = $90
+    ;; Counter for frame drops. Only touched when PARTIAL is defined.
+    zp_frame_drops = $90        ; asan:ignore
 .endscope
 
 ;; Pretty standard reset function, nothing crazy.
@@ -17,7 +17,7 @@
 
     ;; Disable APU frame counter.
     ldx #$40
-    stx APU::FRAME_COUNTER
+    stx APU::m_frame_counter
 
     ;; Setup the stack.
     ldx #$FF
@@ -25,14 +25,14 @@
 
     ;; Disable NMIs and the APU's DMC.
     inx
-    stx PPU::CONTROL
-    stx PPU::MASK
-    stx APU::DMC
+    stx PPU::m_control
+    stx PPU::m_mask
+    stx APU::m_dmc
 
     ;; First PPU wait.
-    bit PPU::STATUS
+    bit PPU::m_status
 @vblankwait1:
-    bit PPU::STATUS
+    bit PPU::m_status
     bpl @vblankwait1
 
     ;; Initialize the counter for frame drops before any NMIs can come in.
@@ -45,7 +45,7 @@
     lda #$EF
     ldx #0
 @sprite_reset_loop:
-    sta $200, x
+    sta OAM::m_sprites, x
     inx
     inx
     inx
@@ -54,13 +54,13 @@
 
     ;; DMA setup for sprite reset.
     lda #$00
-    sta OAM::ADDRESS
+    sta OAM::m_address
     lda #$02
-    sta OAM::DMA
+    sta OAM::m_dma
 
     ;; Second PPU wait. After that the PPU is stable.
 @vblankwait2:
-    bit PPU::STATUS
+    bit PPU::m_status
     bpl @vblankwait2
 
     ;; NOTE: palettes are not initialized here as it's going to be one of the
@@ -89,9 +89,9 @@
 
     ;; Sprite DMA.
     lda #$00
-    sta OAM::ADDRESS
+    sta OAM::m_address
     lda #$02
-    sta OAM::DMA
+    sta OAM::m_dma
 
     ;; Are we paused? If so skip timers, PAL handler and the likes.
     lda #%00001000
@@ -126,20 +126,20 @@
     and Globals::zp_flags
     sta Globals::zp_flags
 
-    bit PPU::STATUS
+    bit PPU::m_status
 
     ;; Update the PPU control/mask registers with shadowed values.
     lda PPU::zp_mask
-    sta PPU::MASK
+    sta PPU::m_mask
     lda PPU::zp_control
-    sta PPU::CONTROL
+    sta PPU::m_control
 
 @scroll:
     ;; Always reset the scroll just in case.
-    bit PPU::STATUS
+    bit PPU::m_status
     lda #$00
-    sta PPU::SCROLL
-    sta PPU::SCROLL
+    sta PPU::m_scroll
+    sta PPU::m_scroll
 
     ;; Unblock the main code.
     lda #%01111111