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>

5 files changed, 28 insertions, 27 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.