Add support for continuous integration in GitHub

.github/workflows/ci.yaml

@@ -0,0 +1,51 @@
+name: CI for Ex6502
+
+on: push
+
+permissions:
+  contents: read
+
+jobs:
+  lint:
+    name: Code quality for Ex6502
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        otp: ["26.2.3"]
+        elixir: ["1.16.2-otp-26"]
+    env:
+      MIX_ENV: test
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Setup elixir
+        uses: erlef/setup-beam@v1
+        with:
+          otp-version: ${{ matrix.otp }}
+          elixir-version: ${{ matrix.elixir }}
+
+      - name: Cache deps
+        uses: actions/cache@v3
+        with:
+          key: deps-${{ runner.os }}-${{ matrix.otp }}-${{ matrix.elixir }}-${{ hashFiles('**/mix.lock', '**/mix.exs') }}
+          path: ./deps
+
+      - name: Cache build
+        uses: actions/cache@v3
+        with:
+          key: build-${{ runner.os }}-${{ matrix.otp }}-${{ matrix.elixir }}-${{ hashFiles('**/mix.lock', '**/mix.exs') }}
+          path: ./_build
+
+      - name: Cache priv
+        uses: actions/cache@v3
+        with:
+          key: priv-${{ runner.os }}-${{ matrix.otp }}-${{ matrix.elixir }}-${{ hashFiles('**/mix.lock', '**/mix.exs') }}
+          path: ./priv
+
+      - run: mix deps.get
+      - run: mix compile --warnings-as-errors
+      - run: mix format --check-formatted
+      - run: mix dialyzer --format github
+      - run: mix test

.gitignore

@@ -22,6 +22,9 @@ erl_crash.dump
 # Ignore package tarball (built via "mix hex.build").
 ex6502-*.tar
 
+# Ignore dialyzer plt files
+/priv/plts/*.plt
+/priv/plts/*.plt.hash
 
 # Temporary files for e.g. tests
 /tmp

dialyzer_ignore.exs

@@ -0,0 +1,2 @@
+[
+]

lib/ex6502/computer.ex

@@ -1,6 +1,6 @@
 defmodule Ex6502.Computer do
   alias Ex6502.{Computer, CPU, Memory}
-  use Bitwise
+  import Bitwise
 
   defstruct break: false,
             cpu: %Ex6502.CPU{},
@@ -14,11 +14,7 @@ defmodule Ex6502.Computer do
   @reset_vector 0xFFFC
 
   def init(opts \\ []) do
-    memory =
-      opts[:memory] ||
-        with {:ok, memory} <- Memory.init(0xFFFF) do
-          memory
-        end
+    memory = Keyword.get_lazy(opts, :memory, fn -> Memory.init(0xFFFF) end)
 
     %Computer{cpu: CPU.init(), memory: memory}
     |> reset()

lib/ex6502/cpu.ex

@@ -26,7 +26,7 @@ defmodule Ex6502.CPU do
   * `$FFFE` - IRQ
   """
 
-  use Bitwise
+  import Bitwise
 
   alias Ex6502.{Computer, CPU}
 

lib/ex6502/cpu/executor/adc.ex

@@ -39,7 +39,7 @@ defmodule Ex6502.CPU.Executor.ADC do
 
   alias Ex6502.{Computer, CPU, Memory}
 
-  use Bitwise
+  import Bitwise
 
   def execute(%Computer{} = c) do
     if CPU.flag(c, :d), do: raise(RuntimeError, "Decimal mode is not yet supported")

lib/ex6502/cpu/executor/and.ex

@@ -33,7 +33,7 @@ defmodule Ex6502.CPU.Executor.AND do
 
   alias Ex6502.{Computer, CPU, Memory}
 
-  use Bitwise
+  import Bitwise
 
   # AND #$nn Immediate $29
   def execute(%Computer{data_bus: 0x29} = c) do

lib/ex6502/cpu/executor/asl.ex

@@ -32,7 +32,7 @@ defmodule Ex6502.CPU.Executor.ASL do
 
   alias Ex6502.{Computer, CPU, Memory}
 
-  use Bitwise
+  import Bitwise
 
   # ASL A $0A
   def execute(%Computer{data_bus: 0x0A} = c) do

lib/ex6502/cpu/executor/bit.ex

@@ -37,7 +37,7 @@ defmodule Ex6502.CPU.Executor.BIT do
 
   alias Ex6502.{Computer, CPU, Memory}
 
-  use Bitwise
+  import Bitwise
 
   # BIT #$nn Immediate $29
   def execute(%Computer{data_bus: 0x89} = c) do

lib/ex6502/cpu/executor/bra.ex

@@ -26,8 +26,6 @@ defmodule Ex6502.CPU.Executor.BRA do
   alias Ex6502.{Computer, CPU}
   import CPU.Executor.Branching
 
-  use Bitwise
-
   # addressing       assembler    opc  bytes  cycles
   # relative         BRA $nnnn    80     2     3 tp
   def execute(%Computer{data_bus: 0x80} = c), do: branch(c, true)

lib/ex6502/cpu/executor/brk.ex

@@ -36,7 +36,7 @@ defmodule Ex6502.CPU.Executor.BRK do
 
   alias Ex6502.{Computer, CPU}
 
-  use Bitwise
+  import Bitwise
 
   def execute(%Computer{data_bus: 0x00} = c) do
     # flow from https://www.pagetable.com/?p=410

lib/ex6502/cpu/executor/cmp.ex

@@ -37,8 +37,6 @@ defmodule Ex6502.CPU.Executor.CMP do
 
   alias Ex6502.{Computer, CPU, Memory}
 
-  use Bitwise
-
   def execute(%Computer{} = c) do
     c
     |> do_execute()

lib/ex6502/cpu/executor/cpx.ex

@@ -29,8 +29,6 @@ defmodule Ex6502.CPU.Executor.CPX do
 
   alias Ex6502.{Computer, CPU, Memory}
 
-  use Bitwise
-
   def execute(%Computer{} = c) do
     c
     |> do_execute()

lib/ex6502/cpu/executor/cpy.ex

@@ -29,8 +29,6 @@ defmodule Ex6502.CPU.Executor.CPY do
 
   alias Ex6502.{Computer, CPU, Memory}
 
-  use Bitwise
-
   def execute(%Computer{} = c) do
     c
     |> do_execute()

lib/ex6502/cpu/executor/dec.ex

@@ -30,7 +30,7 @@ defmodule Ex6502.CPU.Executor.DEC do
 
   alias Ex6502.{Computer, CPU, Memory}
 
-  use Bitwise
+  import Bitwise
 
   # This is a special mode that needs its own special function
   #

lib/ex6502/cpu/executor/dex.ex

@@ -26,7 +26,7 @@ defmodule Ex6502.CPU.Executor.DEX do
 
   alias Ex6502.{Computer, CPU}
 
-  use Bitwise
+  import Bitwise
 
   # addressing       assembler    opc  bytes  cycles
   # implied          DEX           CA    1     2

lib/ex6502/cpu/executor/dey.ex

@@ -26,7 +26,7 @@ defmodule Ex6502.CPU.Executor.DEY do
 
   alias Ex6502.{Computer, CPU}
 
-  use Bitwise
+  import Bitwise
 
   # addressing       assembler    opc  bytes  cycles
   # implied          DEY           88    1      2

lib/ex6502/cpu/executor/eor.ex

@@ -34,12 +34,12 @@ defmodule Ex6502.CPU.Executor.EOR do
 
   alias Ex6502.{Computer, CPU, Memory}
 
-  use Bitwise
+  import Bitwise
 
   # EOR #$nn Immediate $49
   def execute(%Computer{data_bus: 0x49} = c) do
     with %Computer{data_bus: value} = c <- Computer.put_next_byte_on_data_bus(c),
-         result <- value ^^^ c.cpu.a do
+         result <- bxor(value, c.cpu.a) do
       c
       |> CPU.set(:a, result)
       |> CPU.set_flags([:n, :z], result)
@@ -50,7 +50,7 @@ defmodule Ex6502.CPU.Executor.EOR do
   def execute(%Computer{data_bus: 0x4D} = c) do
     with c <- Computer.put_absolute_address_on_bus(c),
          %Computer{data_bus: value} <- Memory.absolute(c),
-         result <- value ^^^ c.cpu.a do
+         result <- bxor(value, c.cpu.a) do
       c
       |> CPU.set(:a, result)
       |> CPU.set_flags([:n, :z], :a)
@@ -61,7 +61,7 @@ defmodule Ex6502.CPU.Executor.EOR do
   def execute(%Computer{data_bus: 0x5D} = c) do
     with c <- Computer.put_absolute_address_on_bus(c),
          %Computer{data_bus: value} <- Memory.absolute(c, c.cpu.x),
-         result <- value ^^^ c.cpu.a do
+         result <- bxor(value, c.cpu.a) do
       c
       |> CPU.set(:a, result)
       |> CPU.set_flags([:n, :z], :a)
@@ -72,7 +72,7 @@ defmodule Ex6502.CPU.Executor.EOR do
   def execute(%Computer{data_bus: 0x59} = c) do
     with c <- Computer.put_absolute_address_on_bus(c),
          %Computer{data_bus: value} <- Memory.absolute(c, c.cpu.y),
-         result <- value ^^^ c.cpu.a do
+         result <- bxor(value, c.cpu.a) do
       c
       |> CPU.set(:a, result)
       |> CPU.set_flags([:n, :z], :a)
@@ -83,7 +83,7 @@ defmodule Ex6502.CPU.Executor.EOR do
   def execute(%Computer{data_bus: 0x45} = c) do
     with c <- Computer.put_zero_page_on_address_bus(c),
          %Computer{data_bus: value} <- Memory.absolute(c),
-         result <- value ^^^ c.cpu.a do
+         result <- bxor(value, c.cpu.a) do
       c
       |> CPU.set(:a, result)
       |> CPU.set_flags([:n, :z], :a)
@@ -94,7 +94,7 @@ defmodule Ex6502.CPU.Executor.EOR do
   def execute(%Computer{data_bus: 0x55} = c) do
     with c <- Computer.put_zero_page_on_address_bus(c, c.cpu.x),
          %Computer{data_bus: value} <- Memory.absolute(c),
-         result <- value ^^^ c.cpu.a do
+         result <- bxor(value, c.cpu.a) do
       c
       |> CPU.set(:a, result)
       |> CPU.set_flags([:n, :z], :a)
@@ -105,7 +105,7 @@ defmodule Ex6502.CPU.Executor.EOR do
   def execute(%Computer{data_bus: 0x52} = c) do
     with c <- Computer.put_zero_page_on_address_bus(c),
          %Computer{data_bus: value} <- Memory.indirect(c),
-         result <- value ^^^ c.cpu.a do
+         result <- bxor(value, c.cpu.a) do
       c
       |> CPU.set(:a, result)
       |> CPU.set_flags([:n, :z], :a)
@@ -116,7 +116,7 @@ defmodule Ex6502.CPU.Executor.EOR do
   def execute(%Computer{data_bus: 0x41} = c) do
     with c <- Computer.put_zero_page_on_address_bus(c, c.cpu.x),
          %Computer{data_bus: value} <- Memory.indirect(c),
-         result <- value ^^^ c.cpu.a do
+         result <- bxor(value, c.cpu.a) do
       c
       |> CPU.set(:a, result)
       |> CPU.set_flags([:n, :z], :a)
@@ -127,7 +127,7 @@ defmodule Ex6502.CPU.Executor.EOR do
   def execute(%Computer{data_bus: 0x51} = c) do
     with c <- Computer.put_zero_page_on_address_bus(c),
          %Computer{data_bus: value} <- Memory.indirect(c, c.cpu.y),
-         result <- value ^^^ c.cpu.a do
+         result <- bxor(value, c.cpu.a) do
       c
       |> CPU.set(:a, result)
       |> CPU.set_flags([:n, :z], :a)

lib/ex6502/cpu/executor/inc.ex

@@ -30,7 +30,7 @@ defmodule Ex6502.CPU.Executor.INC do
 
   alias Ex6502.{Computer, CPU, Memory}
 
-  use Bitwise
+  import Bitwise
 
   # This is a special mode that needs its own special function
   #

lib/ex6502/cpu/executor/inx.ex

@@ -26,7 +26,7 @@ defmodule Ex6502.CPU.Executor.INX do
 
   alias Ex6502.{Computer, CPU}
 
-  use Bitwise
+  import Bitwise
 
   # addressing       assembler    opc  bytes  cycles
   # implied          INX           E8    1      2

lib/ex6502/cpu/executor/iny.ex

@@ -26,7 +26,7 @@ defmodule Ex6502.CPU.Executor.INY do
 
   alias Ex6502.{Computer, CPU}
 
-  use Bitwise
+  import Bitwise
 
   # addressing       assembler    opc  bytes  cycles
   # implied          INY           C8    1      2

lib/ex6502/cpu/executor/lsr.ex

@@ -32,7 +32,7 @@ defmodule Ex6502.CPU.Executor.LSR do
 
   alias Ex6502.{Computer, CPU, Memory}
 
-  use Bitwise
+  import Bitwise
 
   # LSR A accumaltor $4A
   def execute(%Computer{data_bus: 0x4A} = c) do

lib/ex6502/cpu/executor/ora.ex

@@ -34,7 +34,7 @@ defmodule Ex6502.CPU.Executor.ORA do
 
   alias Ex6502.{Computer, CPU, Memory}
 
-  use Bitwise
+  import Bitwise
 
   # ORA #$nn Immediate $09
   def execute(%Computer{data_bus: 0x09} = c) do

lib/ex6502/cpu/executor/rol.ex

@@ -33,7 +33,7 @@ defmodule Ex6502.CPU.Executor.ROL do
 
   alias Ex6502.{Computer, CPU, Memory}
 
-  use Bitwise
+  import Bitwise
 
   # ROL A accumulator $2A
   def execute(%Computer{data_bus: 0x2A} = c) do

lib/ex6502/cpu/executor/ror.ex

@@ -33,7 +33,7 @@ defmodule Ex6502.CPU.Executor.ROR do
 
   alias Ex6502.{Computer, CPU, Memory}
 
-  use Bitwise
+  import Bitwise
 
   # ROR A accumulator $6A
   def execute(%Computer{data_bus: 0x6A} = c) do

lib/ex6502/cpu/executor/sbc.ex

@@ -45,7 +45,7 @@ defmodule Ex6502.CPU.Executor.SBC do
 
   alias Ex6502.{Computer, CPU, Memory}
 
-  use Bitwise
+  import Bitwise
 
   def execute(%Computer{} = c) do
     c
@@ -73,7 +73,7 @@ defmodule Ex6502.CPU.Executor.SBC do
     # 7FH (+ 127,0) and 80H with C = 1 (i.e., ‐12810).
     #
     # see www.righto.com/2012/12/the-6502-overflow-flag-explained.html
-    |> CPU.set_flag(:v, (c.cpu.a ^^^ result &&& (255 - value) ^^^ result &&& 0x80) != 0)
+    |> CPU.set_flag(:v, (bxor(c.cpu.a, result) &&& bxor(255 - value, result) &&& 0x80) != 0)
     |> CPU.set_flags([:n, :z], :a)
   end
 

lib/ex6502/cpu/executor/trb.ex

@@ -28,7 +28,7 @@ defmodule Ex6502.CPU.Executor.TRB do
 
   alias Ex6502.{Computer, CPU, Memory}
 
-  use Bitwise
+  import Bitwise
 
   # TRB $nnnn absolute $1C
   def execute(%Computer{data_bus: 0x1C} = c) do

lib/ex6502/cpu/executor/tsb.ex

@@ -28,7 +28,7 @@ defmodule Ex6502.CPU.Executor.TSB do
 
   alias Ex6502.{Computer, CPU, Memory}
 
-  use Bitwise
+  import Bitwise
 
   # TSB $nnnn absolute $0C
   def execute(%Computer{data_bus: 0x0C} = c) do

lib/ex6502/disassembler.ex

@@ -1,7 +1,7 @@
 defmodule Ex6502.Disassembler do
   alias Ex6502.{Computer, Memory}
 
-  use Bitwise
+  import Bitwise
 
   def disassemble(%Computer{cpu: %{pc: pc}, memory: memory}) do
     case Memory.get(memory, pc, 3) do