Moves ADC specific logic out of CPU

app/src/main/kotlin/android/emu6502/CPU.kt

@@ -192,50 +192,6 @@ class CPU(val memory: Memory) : Display.Callbacks {
     return popByte() + popByte().shl(8)
   }
 
-  fun testADC(value: Int) {
-    var tmp: Int
-    if (A.xor(value).and(0x80) != 0) {
-      CLV()
-    } else {
-      setOverflow()
-    }
-
-    if (decimalMode()) {
-      tmp = A.and(0xf) + value.and(0xf) + P.and(1)
-      if (tmp >= 10) {
-        tmp = 0x10.or((tmp + 6).and(0xf))
-      }
-      tmp += A.and(0xf0) + value.and(0xf0)
-      if (tmp >= 160) {
-        SEC()
-        if (overflow() && tmp >= 0x180) {
-          CLV()
-        }
-        tmp += 0x60
-      } else {
-        CLC()
-        if (overflow() && tmp < 0x80) {
-          CLV()
-        }
-      }
-    } else {
-      tmp = A + value + P.and(1)
-      if (tmp >= 0x100) {
-        SEC()
-        if (overflow() && tmp >= 0x180) {
-          CLV()
-        }
-      } else {
-        CLC()
-        if (overflow() && tmp < 0x80) {
-          CLV()
-        }
-      }
-    }
-    A = tmp.and(0xff)
-    setSZFlagsForRegA()
-  }
-
   fun overflow(): Boolean {
     return P.and(0x40) != 0
   }

app/src/main/kotlin/android/emu6502/instructions/impl/ADC.kt

@@ -7,6 +7,50 @@ import android.emu6502.instructions.Instruction
 /** ADd with Carry */
 class ADC(private val cpu: CPU) : BaseInstruction(Instruction.ADC, cpu.instructionList) {
   override fun immediate() {
-    cpu.testADC(cpu.popByte())
+    testADC(cpu.popByte())
+  }
+
+  private fun testADC(value: Int) {
+    var tmp: Int
+    if (cpu.A.xor(value).and(0x80) != 0) {
+      cpu.CLV()
+    } else {
+      cpu.setOverflow()
+    }
+
+    if (cpu.decimalMode()) {
+      tmp = cpu.A.and(0xf) + value.and(0xf) + cpu.P.and(1)
+      if (tmp >= 10) {
+        tmp = 0x10.or((tmp + 6).and(0xf))
+      }
+      tmp += cpu.A.and(0xf0) + value.and(0xf0)
+      if (tmp >= 160) {
+        cpu.SEC()
+        if (cpu.overflow() && tmp >= 0x180) {
+          cpu.CLV()
+        }
+        tmp += 0x60
+      } else {
+        cpu.CLC()
+        if (cpu.overflow() && tmp < 0x80) {
+          cpu.CLV()
+        }
+      }
+    } else {
+      tmp = cpu.A + value + cpu.P.and(1)
+      if (tmp >= 0x100) {
+        cpu.SEC()
+        if (cpu.overflow() && tmp >= 0x180) {
+          cpu.CLV()
+        }
+      } else {
+        cpu.CLC()
+        if (cpu.overflow() && tmp < 0x80) {
+          cpu.CLV()
+        }
+      }
+    }
+    cpu.A = tmp.and(0xff)
+    cpu.setSZFlagsForRegA()
   }
 }