More stuff

Zelda no Densetsu - Kamigami no Triforce (Japan).json

@@ -3,6 +3,7 @@
     "008000" : {
       "label" : "ResetVector"
     },
+    "00800a" : { },
     "00801b" : {
       "comment" : "\\ Turn off emulation mode"
     },

src/main/java/com/smallhacker/disbrowser/Service.kt

@@ -10,28 +10,27 @@ import kotlin.reflect.KMutableProperty1
 private val RESET_VECTOR_LOCATION = address(0x00_FFFC)
 
 object Service {
-    private val romName = "Zelda no Densetsu - Kamigami no Triforce (Japan)"
+    private const val romName = "Zelda no Densetsu - Kamigami no Triforce (Japan)"
     private val romDir = Paths.get("""P:\Emulation\ROMs\SNES""")
     private val metaDir = Paths.get("""P:\Programming\dis-browser""")
     private val metaFile = jsonFile<Metadata>(metaDir.resolve("$romName.json"), true)
     private val metadata by lazy { metaFile.load() }
 
-    private val romData = lazy {
+    private val snesMemory by lazy {
         val path = romDir.resolve("$romName.sfc")
-        RomData.load(path)
+        SnesLoRom(loadRomData(path))
     }
 
     fun showDisassemblyFromReset(): HtmlNode? {
-        val resetVectorLocation = RESET_VECTOR_LOCATION
+        val resetVector = snesMemory.getWord(RESET_VECTOR_LOCATION)
-        val initialAddress = SnesAddress(romData.value.getWord(resetVectorLocation.pc).toUInt24())
+        val fullResetVector = resetVector!!.toUInt24()
+        val initialAddress = SnesAddress(fullResetVector)
         val flags = VagueNumber(0x30u)
         return showDisassembly(initialAddress, flags)
     }
 
     fun showDisassembly(initialAddress: SnesAddress, flags: VagueNumber): HtmlNode? {
-        val rom = romData.value
+        val initialState = State(memory = snesMemory, address = initialAddress, flags = flags)
-
-        val initialState = State(data = rom, address = initialAddress, flags = flags)
         val disassembly = Disassembler.disassemble(initialState, metadata, false)
 
         return print(disassembly, metadata)

src/main/java/com/smallhacker/disbrowser/asm/Instruction.kt

@@ -12,7 +12,7 @@ interface CodeUnit {
     val preState: State?
     val postState: State?
 
-    val bytes: RomData
+    val bytes: ValidMemorySpace
     val opcode: Opcode
     val lengthSuffix: String?
 
@@ -62,7 +62,7 @@ interface CodeUnit {
 
 class DataBlock(
         override val opcode: Opcode,
-        override val bytes: RomData,
+        override val bytes: ValidMemorySpace,
         override val presentedAddress: SnesAddress,
         override val relativeAddress: SnesAddress,
         override val linkedState: State?
@@ -77,7 +77,7 @@ class DataBlock(
     override val lengthSuffix: String? = null
 }
 
-class Instruction(override val bytes: RomData, override val opcode: Opcode, override val preState: State) : CodeUnit {
+class Instruction(override val bytes: ValidMemorySpace, override val opcode: Opcode, override val preState: State) : CodeUnit {
     override val address: SnesAddress get() = preState.address
     override val relativeAddress get() = address
     override val presentedAddress get() = address
@@ -115,18 +115,59 @@ class Instruction(override val bytes: RomData, override val opcode: Opcode, over
             return null
         }
 
+        return referencedAddress()
+
+//        return when (opcode.mode) {
+//            Mode.ABSOLUTE_CODE -> preState.resolveAbsoluteCode(word)
+//            Mode.ABSOLUTE_LONG -> SnesAddress(long)
+//            Mode.RELATIVE -> relativeAddress + 2 + signedByte.toInt()
+//            Mode.RELATIVE_LONG -> relativeAddress + 3 + signedWord.toInt()
+//            Mode.CODE_WORD -> preState.resolveAbsoluteCode(word)
+//            Mode.CODE_LONG -> SnesAddress(long)
+//            Mode.DATA_WORD -> preState.resolveAbsoluteData(word)
+//            Mode.DATA_LONG -> SnesAddress(long)
+//            else -> null
+//        }
+    }
+
+    private fun referencedAddress(): SnesAddress? {
         return when (opcode.mode) {
-            Mode.ABSOLUTE -> relativeAddress.withinBank(word)
+            Mode.ABSOLUTE -> preState.resolveAbsoluteData(word)
+            Mode.ABSOLUTE_CODE -> preState.resolveAbsoluteCode(word)
+            Mode.ABSOLUTE_INDIRECT -> preState.resolveAbsoluteData(word)
+            Mode.ABSOLUTE_INDIRECT_LONG -> preState.resolveAbsoluteData(word)
             Mode.ABSOLUTE_LONG -> SnesAddress(long)
+            Mode.ABSOLUTE_LONG_X -> SnesAddress(long)
+            Mode.ABSOLUTE_X -> preState.resolveAbsoluteData(word)
+            Mode.ABSOLUTE_X_INDIRECT -> preState.resolveAbsoluteData(word)
+            Mode.ABSOLUTE_Y -> preState.resolveAbsoluteData(word)
+            Mode.BLOCK_MOVE -> null
+            Mode.CODE_WORD -> preState.resolveAbsoluteCode(word)
+            Mode.CODE_LONG -> SnesAddress(long)
+            Mode.DATA_BYTE -> null
+            Mode.DATA_WORD -> preState.resolveAbsoluteData(word)
+            Mode.DATA_LONG -> SnesAddress(long)
+            Mode.DIRECT -> preState.resolveDirectPage(byte)
+            Mode.DIRECT_X -> preState.resolveDirectPage(byte)
+            Mode.DIRECT_Y -> preState.resolveDirectPage(byte)
+            Mode.DIRECT_S -> null
+            Mode.DIRECT_INDIRECT -> preState.resolveDirectPage(byte)
+            Mode.DIRECT_INDIRECT_Y -> preState.resolveDirectPage(byte)
+            Mode.DIRECT_X_INDIRECT -> preState.resolveDirectPage(byte)
+            Mode.DIRECT_S_INDIRECT_Y -> null
+            Mode.DIRECT_INDIRECT_LONG -> preState.resolveDirectPage(byte)
+            Mode.DIRECT_INDIRECT_LONG_Y -> preState.resolveDirectPage(byte)
+            Mode.IMMEDIATE_8 -> null
+            Mode.IMMEDIATE_16 -> null
+            Mode.IMMEDIATE_M -> null
+            Mode.IMMEDIATE_X -> null
+            Mode.IMPLIED -> null
             Mode.RELATIVE -> relativeAddress + 2 + signedByte.toInt()
             Mode.RELATIVE_LONG -> relativeAddress + 3 + signedWord.toInt()
-            Mode.DATA_WORD -> relativeAddress.withinBank(word)
-            Mode.DATA_LONG -> SnesAddress(long)
-            else -> null
         }
     }
 
     override fun toString(): String {
         return "$address ${bytesToString()} ${opcode.mnemonic.displayName} ${opcode.mode.print(this).padEnd(100, ' ')} ($preState -> $postState)"
     }
-}
+}

src/main/java/com/smallhacker/disbrowser/asm/MemorySpace.kt

@@ -0,0 +1,93 @@
+package com.smallhacker.disbrowser.asm
+
+import com.smallhacker.disbrowser.util.UInt24
+import com.smallhacker.disbrowser.util.joinBytes
+import com.smallhacker.disbrowser.util.joinNullableBytes
+import com.smallhacker.disbrowser.util.toUInt24
+import java.nio.file.Files
+import java.nio.file.Path
+
+interface MemorySpace {
+    val size: UInt
+    operator fun get(address: UInt): UByte?
+}
+
+interface ValidMemorySpace : MemorySpace {
+    override operator fun get(address: UInt): UByte
+}
+
+object EmptyMemorySpace : ValidMemorySpace {
+    override val size get() = 0u
+    override fun get(address: UInt) = throw IllegalStateException()
+}
+
+fun MemorySpace.asSequence(): Sequence<UByte?> = (0u until size).asSequence().map { this[it] }
+fun MemorySpace.getWord(address: UInt): UShort? = joinNullableBytes(this[address], this[address + 1u])?.toUShort()
+fun MemorySpace.getLong(address: UInt): UInt24? = joinNullableBytes(this[address], this[address + 1u], this[address + 2u])?.toUInt24()
+fun MemorySpace.range(start: UInt, length: UInt): MemorySpace = MemoryRange(this, start, length)
+fun MemorySpace.range(start: SnesAddress, length: UInt): MemorySpace = range(start.value.toUInt(), length)
+fun MemorySpace.validate(): ValidMemorySpace? {
+    if (asSequence().any { it == null }) {
+        return null
+    }
+    return ValidatedMemorySpace(this)
+}
+
+fun ValidMemorySpace.asSequence(): Sequence<UByte> = (0u until size).asSequence().map { this[it] }
+fun ValidMemorySpace.getWord(address: UInt): UShort = joinBytes(this[address], this[address + 1u]).toUShort()
+fun ValidMemorySpace.getLong(address: UInt): UInt24 = joinBytes(this[address], this[address + 1u], this[address + 2u]).toUInt24()
+fun ValidMemorySpace.range(start: UInt, length: UInt): ValidMemorySpace = MemoryRange(this, start, length).validate()!!
+fun ValidMemorySpace.range(start: SnesAddress, length: UInt): ValidMemorySpace = range(start.value.toUInt(), length).validate()!!
+
+fun loadRomData(path: Path): MemorySpace {
+    val bytes = Files.readAllBytes(path).toUByteArray()
+    return ArrayMemorySpace(bytes)
+}
+
+class ArrayMemorySpace(private val bytes: UByteArray) : MemorySpace {
+    override val size = bytes.size.toUInt()
+
+    override fun get(address: UInt): UByte? {
+        if (address >= size) {
+            return null
+        }
+        return bytes[address.toInt()]
+    }
+}
+
+class UnreadableMemory(override val size: UInt) : MemorySpace {
+    override fun get(address: UInt): UByte? = null
+}
+
+private class MemoryRange(private val parent: MemorySpace, private val start: UInt, override val size: UInt) : MemorySpace {
+    override fun get(address: UInt) = if (address < size) parent[start + address] else null
+}
+
+
+private class ValidatedMemorySpace(private val parent: MemorySpace) : ValidMemorySpace {
+    override val size get() = parent.size
+    override fun get(address: UInt) = parent[address]!!
+}
+
+private class ReindexedMemorySpace(
+        private val parent: MemorySpace,
+        override val size: UInt,
+        private val mapper: (UInt) -> UInt
+) : MemorySpace {
+    override fun get(address: UInt): UByte? {
+        if (address >= size) {
+            return null
+        }
+        val mapped = mapper(address)
+        return parent[mapped]
+    }
+}
+
+fun MemorySpace.deinterleave(entries: UInt, vararg startOffsets: UInt): MemorySpace {
+    val fieldCount = startOffsets.size.toUInt()
+    return ReindexedMemorySpace(this, entries * fieldCount) {
+        val entry = it / fieldCount
+        val field = it.rem(fieldCount)
+        startOffsets[field.toInt()] + entry
+    }
+}

src/main/java/com/smallhacker/disbrowser/asm/Metadata.kt

@@ -1,8 +1,11 @@
 package com.smallhacker.disbrowser.asm
 
-import com.fasterxml.jackson.annotation.*
+import com.fasterxml.jackson.annotation.JsonCreator
+import com.fasterxml.jackson.annotation.JsonProperty
+import com.fasterxml.jackson.annotation.JsonSubTypes
 import com.fasterxml.jackson.annotation.JsonSubTypes.Type
-import com.smallhacker.disbrowser.util.joinBytes
+import com.fasterxml.jackson.annotation.JsonTypeInfo
+import com.smallhacker.disbrowser.util.joinNullableBytes
 import com.smallhacker.disbrowser.util.toUInt24
 import java.util.*
 
@@ -63,20 +66,20 @@ class JmpIndirectLongInterleavedTable @JsonCreator constructor(
 ) : InstructionFlag {
     private val uEntries get() = entries.toUInt()
 
-    fun readTable(data: RomData): Sequence<SnesAddress> {
+    fun readTable(data: MemorySpace): Sequence<SnesAddress?> {
-        return (0u until uEntries)
+        return (0 until entries)
                 .asSequence()
-                .map { it + start.pc }
+                .map { start + it }
-                .map { pc -> joinBytes(data[pc], data[pc + uEntries], data[pc + uEntries + uEntries]).toUInt24() }
+                .map { address -> joinNullableBytes(data[address], data[address + entries], data[address + entries + entries])?.toUInt24() }
-                .map { SnesAddress(it) }
+                .map { pointer -> pointer?.let { SnesAddress(it) } }
     }
 
     fun generateCode(jumpInstruction: Instruction): Sequence<DataBlock> {
-        val table = jumpInstruction.preState.data.deinterleave(uEntries,
+        val table = jumpInstruction.preState.memory.deinterleave(uEntries,
-                start.pc,
+                start.value.toUInt(),
-                (start + entries).pc,
+                (start + entries).value.toUInt(),
-                (start + (2u * uEntries).toInt()).pc
+                (start + (2 * uEntries.toInt())).value.toUInt()
-        )
+        ).validate() ?: return emptySequence()
 
         return (0u until uEntries)
                 .asSequence()
@@ -93,11 +96,6 @@ class JmpIndirectLongInterleavedTable @JsonCreator constructor(
                                     .mutateAddress { SnesAddress(target) }
                                     .withOrigin(jumpInstruction)
                     )
-//                    Instruction(
-//                            data.range((start.value + offset).toUInt(), 3u),
-//                            Opcode.POINTER_LONG,
-//                            preState.mutateAddress { start -> start + offset.toInt() }
-//                    )
                 }
     }
 
@@ -108,13 +106,13 @@ class JslTableRoutine @JsonCreator constructor(
         @field:JsonProperty @JsonProperty private val entries: Int
 ) : InstructionFlag {
 
-    fun readTable(postJsr: State): Sequence<SnesAddress> {
+    fun readTable(postJsr: State): Sequence<SnesAddress?> {
-        val data = postJsr.data
+        val data = postJsr.memory
-        return (0u until entries.toUInt())
+        return (0 until entries)
                 .asSequence()
-                .map { postJsr.address.pc + (it * 3u) }
+                .map { postJsr.address + (it * 3) }
-                .map { pc -> joinBytes(data[pc], data[pc + 1u], data[pc + 2u]).toUInt24() }
+                .map { address -> joinNullableBytes(data[address], data[address + 1], data[address + 2])?.toUInt24() }
-                .map { SnesAddress(it) }
+                .map { pointer -> pointer?.let { SnesAddress(it) } }
     }
 
     override fun toString() = "JslTableRoutine($entries)"

src/main/java/com/smallhacker/disbrowser/asm/Mnemonic.kt

@@ -11,7 +11,8 @@ enum class Mnemonic(private val nameOverride: String? = null, val alternativeNam
     TCS, TDC, TRB, TSB, TSC, TSX, TXA, TXS, TXY, TYA, TYX,
     WAI, WDM, XBA, XCE,
 
-    DB(nameOverride = ".db"), DW(nameOverride = ".dw"), DL(nameOverride = ".dl");
+    DB(nameOverride = ".db"), DW(nameOverride = ".dw"), DL(nameOverride = ".dl"),
+    UNKNOWN(nameOverride = "???");
 
     val displayName get() = nameOverride ?: name
 }

src/main/java/com/smallhacker/disbrowser/asm/Mode.kt

@@ -15,11 +15,14 @@ enum class Mode {
     DATA_BYTE("$00", dataMode = true, showLengthSuffix = false),
     DATA_WORD("$0000", dataMode = true, showLengthSuffix = false),
     DATA_LONG("$000000", dataMode = true, showLengthSuffix = false),
+    CODE_WORD("$0000", dataMode = true, showLengthSuffix = false),
+    CODE_LONG("$000000", dataMode = true, showLengthSuffix = false),
 
     IMPLIED("", showLengthSuffix = false),
     IMMEDIATE_8("#$00", showLengthSuffix = false),
     IMMEDIATE_16("#$0000", showLengthSuffix = false),
     ABSOLUTE("$0000"),
+    ABSOLUTE_CODE("$0000"),
     ABSOLUTE_X("$0000,x"),
     ABSOLUTE_Y("$0000,y"),
     ABSOLUTE_LONG("$000000"),

src/main/java/com/smallhacker/disbrowser/asm/Opcode.kt

@@ -4,7 +4,6 @@ import java.util.HashMap
 
 import com.smallhacker.disbrowser.asm.Mnemonic.*
 import com.smallhacker.disbrowser.asm.Mode.*
-import com.smallhacker.disbrowser.util.OldUByte
 
 typealias SegmentEnder = Instruction.() -> SegmentEnd?
 
@@ -51,8 +50,10 @@ class Opcode private constructor(val mnemonic: Mnemonic, val mode: Mode, val end
         val DATA_WORD = Opcode(Mnemonic.DW, Mode.DATA_WORD, { null }, { it.preState })
         val DATA_LONG = Opcode(Mnemonic.DL, Mode.DATA_LONG, { null }, { it.preState })
 
-        val POINTER_WORD = Opcode(Mnemonic.DW, Mode.DATA_WORD, { null }, { it.preState }).linking()
+        val POINTER_WORD = Opcode(Mnemonic.DW, Mode.CODE_WORD, { null }, { it.preState }).linking()
-        val POINTER_LONG = Opcode(Mnemonic.DL, Mode.DATA_LONG, { null }, { it.preState }).linking()
+        val POINTER_LONG = Opcode(Mnemonic.DL, Mode.CODE_LONG, { null }, { it.preState }).linking()
+
+        val UNKNOWN_OPCODE: Opcode
 
         private val OPCODES: Array<Opcode>
 
@@ -79,6 +80,7 @@ class Opcode private constructor(val mnemonic: Mnemonic, val mode: Mode, val end
             val dynamicSubJumping: SegmentEnder = { stoppingSegmentEnd(address) }
             val returning: SegmentEnder = { returnSegmentEnd(address) }
 
+            UNKNOWN_OPCODE = Opcode(UNKNOWN, IMPLIED, alwaysStop, Instruction::preState).stop()
 
             add(0x00, BRK, IMMEDIATE_8, alwaysStop).stop()
             add(0x02, COP, IMMEDIATE_8, alwaysStop).stop()
@@ -100,14 +102,14 @@ class Opcode private constructor(val mnemonic: Mnemonic, val mode: Mode, val end
             add(0xF0, BEQ, RELATIVE, branching).branching()
             add(0x82, BRL, RELATIVE_LONG, alwaysBranching).stop().branching()
 
-            add(0x4C, JMP, ABSOLUTE, jumping).linking().stop()
+            add(0x4C, JMP, ABSOLUTE_CODE, jumping).linking().stop()
             add(0x5C, JML, ABSOLUTE_LONG, jumping).linking().stop()
             add(0x6C, JMP, ABSOLUTE_INDIRECT, dynamicJumping).stop()
             add(0x7C, JMP, ABSOLUTE_X_INDIRECT, dynamicJumping).stop()
             add(0xDC, JMP, ABSOLUTE_INDIRECT_LONG, dynamicJumping).stop()
 
             add(0x22, JSL, ABSOLUTE_LONG, subJumping).linking().mayStop()
-            add(0x20, JSR, ABSOLUTE, subJumping).linking().mayStop()
+            add(0x20, JSR, ABSOLUTE_CODE, subJumping).linking().mayStop()
             add(0xFC, JSR, ABSOLUTE_X_INDIRECT, dynamicSubJumping).mayStop()
 
             add(0x60, RTS, IMPLIED, returning).stop()

src/main/java/com/smallhacker/disbrowser/asm/RomData.kt

@@ -1,66 +0,0 @@
-package com.smallhacker.disbrowser.asm
-
-import com.smallhacker.disbrowser.util.*
-import java.nio.file.Files
-import java.nio.file.Path
-
-interface RomData {
-    val size: UInt
-
-    operator fun get(address: UInt): UByte
-
-    fun range(start: UInt, length: UInt): RomData = RomRange(this, start, length)
-
-    fun asSequence(): Sequence<UByte> = (0u until size).asSequence().map { this[it] }
-
-    companion object {
-        fun load(path: Path): RomData = ArrayRomData(Files.readAllBytes(path).toUByteArray())
-    }
-}
-
-fun romData(vararg bytes: UByte): RomData = ArrayRomData(bytes)
-
-fun RomData.getWord(address: UInt) = joinBytes(this[address], this[address + 1u]).toUShort()
-fun RomData.getLong(address: UInt) = joinBytes(this[address], this[address + 1u], this[address + 2u]).toUInt24()
-
-private class ArrayRomData(private val bytes: UByteArray) : RomData {
-    override val size = bytes.size.toUInt()
-
-    override fun get(address: UInt) = rangeChecked(address) {
-        bytes[address.toInt()]
-    }
-
-}
-
-private class RomRange(private val parent: RomData, private val start: UInt, override val size: UInt) : RomData {
-    override fun get(address: UInt) = rangeChecked(address) {
-        parent[start + address]
-    }
-}
-
-private fun <T> RomData.rangeChecked(address: UInt, action: () -> T): T {
-    if (address >= size) {
-        throw IndexOutOfBoundsException("Index $address out of range: [0, $size)")
-    }
-    return action()
-}
-
-private class ReindexedRomData(
-        private val parent: RomData,
-        override val size: UInt,
-        private val mapper: (UInt) -> UInt
-) : RomData {
-    override fun get(address: UInt) = rangeChecked(address) {
-        val mapped = mapper(address)
-        parent[mapped]
-    }
-}
-
-fun RomData.deinterleave(entries: UInt, vararg startOffsets: UInt): RomData {
-    val fieldCount = startOffsets.size.toUInt()
-    return ReindexedRomData(this, entries * fieldCount) {
-        val entry = it / fieldCount
-        val field = it.rem(fieldCount)
-        startOffsets[field.toInt()] + entry
-    }
-}

src/main/java/com/smallhacker/disbrowser/asm/SnesAddress.kt

@@ -7,8 +7,6 @@ import com.smallhacker.disbrowser.util.toUInt24
 import com.smallhacker.disbrowser.util.tryParseInt
 
 data class SnesAddress(val value: UInt24) : Comparable<SnesAddress> {
-    val pc = snesToPc(value)
-
     operator fun plus(offset: Int) = SnesAddress(value + offset)
     operator fun minus(offset: Int) = SnesAddress(value - offset)
     operator fun inc() = plus(1)
@@ -33,10 +31,4 @@ data class SnesAddress(val value: UInt24) : Comparable<SnesAddress> {
     }
 }
 
-fun address(snesAddress: Int) = SnesAddress(snesAddress.toUInt24())
+fun address(snesAddress: Int) = SnesAddress(snesAddress.toUInt24())
-
-private fun snesToPc(value: UInt24): UInt {
-    // TODO: This is incredibly oversimplified. Anything that isn't a small LoROM will crash and burn
-    val intVal = value.toUInt()
-    return (intVal and 0x7FFFu) or ((intVal and 0x7F_0000u) shr 1)
-}

src/main/java/com/smallhacker/disbrowser/asm/SnesMapper.kt

@@ -0,0 +1,86 @@
+package com.smallhacker.disbrowser.asm
+
+import com.smallhacker.disbrowser.datatype.MutableRangeMap
+import com.smallhacker.disbrowser.datatype.NaiveRangeMap
+import com.smallhacker.disbrowser.util.toUInt24
+
+abstract class SnesMapper: MemorySpace {
+    override val size = 0x100_0000u
+    private val areas: MutableRangeMap<UInt, UIntRange, MapperEntry> = NaiveRangeMap()
+
+    protected fun add(start: UInt, canonicalStart: UInt, memorySpace: MemorySpace) {
+        val range = start until (start + memorySpace.size)
+        areas[range] = MapperEntry(start, SnesAddress(canonicalStart.toUInt24()), memorySpace)
+    }
+
+    override fun get(address: UInt): UByte? {
+        val entry = areas[address] ?: return null
+        val offset = address - entry.start
+        return entry.space[offset]
+    }
+
+    fun toCanonical(address: SnesAddress): SnesAddress? {
+        val entry = areas[address.value.toUInt()] ?: return null
+        val offset = address.value - entry.start
+        return entry.canonicalStart + offset.toInt()
+    }
+}
+
+operator fun MemorySpace.get(address: SnesAddress) = get(address.value.toUInt())
+fun MemorySpace.getWord(address: SnesAddress) = getWord(address.value.toUInt())
+fun MemorySpace.getLong(address: SnesAddress) = getLong(address.value.toUInt())
+
+data class MapperEntry(val start: UInt, val canonicalStart: SnesAddress, val space: MemorySpace)
+
+class SnesLoRom(romData: MemorySpace): SnesMapper() {
+    init {
+        val ram = UnreadableMemory(0x2_0000u)
+        val ramMirror = ram.range(0x00_0000u, 0x00_2000u)
+        val registers = UnreadableMemory(0x6_0000u)
+        val sram = UnreadableMemory(0x0_8000u)
+        val ramStart = 0x7e_0000u
+        val regStart = 0x00_2000u
+        val srmStart = 0x70_0000u
+        var pc = 0x00_0000u
+        val high = 0x80_0000u
+
+        for (bank in 0x00u..0x3Fu) {
+            val ramArea = (bank shl 16)
+            val regArea = (bank shl 16) or 0x00_2000u
+            val romArea = (bank shl 16) or 0x00_8000u
+            add(ramArea, ramStart, ramMirror)
+            add(regArea, regStart, registers)
+            add(romArea, romArea, romData.range(pc, 0x00_8000u))
+            add(ramArea + high, ramStart, ramMirror)
+            add(regArea + high, regStart, registers)
+            add(romArea + high, romArea, romData.range(pc, 0x00_8000u))
+            pc += 0x00_8000u
+        }
+
+        for (bank in 0x40u..0x6Fu) {
+            val romArea = (bank shl 16) or 0x00_8000u
+            // Lower half unmapped
+            add(romArea, romArea, romData.range(pc, 0x00_8000u))
+            add(romArea + high, romArea, romData.range(pc, 0x00_8000u))
+            pc += 0x00_8000u
+        }
+
+        for (bank in 0x70u..0x7Du) {
+            val srmArea = (bank shl 16)
+            val romArea = (bank shl 16) or 0x00_8000u
+            add(srmArea, srmStart, sram)
+            add(srmArea + high, srmStart, sram)
+            add(romArea, romArea, romData.range(pc, 0x00_8000u))
+            add(romArea + high, romArea, romData.range(pc, 0x00_8000u))
+            pc += 0x00_8000u
+        }
+
+        for (bank in 0xFEu..0xFFu) {
+            val romArea = (bank shl 16) or 0x00_8000u
+            add(romArea, romArea, romData.range(pc, 0x00_8000u))
+            pc += 0x00_8000u
+        }
+
+        add(ramStart, ramStart, ram)
+    }
+}

src/main/java/com/smallhacker/disbrowser/asm/State.kt

@@ -4,7 +4,7 @@ import com.smallhacker.disbrowser.ImmStack
 import com.smallhacker.disbrowser.immStack
 import com.smallhacker.disbrowser.util.toUInt24
 
-data class State(val origin: Instruction? = null, val data: RomData, val address: SnesAddress, val flags: VagueNumber = VagueNumber(), val stack: ImmStack<VagueNumber> = immStack()) {
+data class State(val origin: Instruction? = null, val memory: SnesMapper, val address: SnesAddress, val flags: VagueNumber = VagueNumber(), val stack: ImmStack<VagueNumber> = immStack()) {
     val m: Boolean? get() = flags.getBoolean(0x20u)
     val x: Boolean? get() = flags.getBoolean(0x10u)
     val db: UByte? get() = pb // TODO
@@ -56,16 +56,21 @@ data class State(val origin: Instruction? = null, val data: RomData, val address
         return "A:${printSize(m)} XY:${printSize(x)} S:" + stackToString()
     }
 
-    fun resolve(directPage: UByte) = dp?.let { dp ->
+    fun resolveDirectPage(directPage: UByte) = dp?.let { dp ->
         val ptr = (dp.toUInt24() shl 8) or (directPage.toUInt24())
         SnesAddress(ptr)
     }
 
-    fun resolve(absolute: UShort)= db?.let { db ->
+    fun resolveAbsoluteData(absolute: UShort) = db?.let { db ->
         val ptr = (db.toUInt24() shl 16) or (absolute.toUInt24())
         SnesAddress(ptr)
     }
 
+    fun resolveAbsoluteCode(absolute: UShort): SnesAddress {
+        val ptr = (pb.toUInt24() shl 16) or (absolute.toUInt24())
+        return SnesAddress(ptr)
+    }
+
     private fun stackToString(): String {
         return stack.reversed().asSequence()
                 .map { stackByteToString(it) }

src/main/java/com/smallhacker/disbrowser/datatype/RangeMap.kt

@@ -0,0 +1,27 @@
+package com.smallhacker.disbrowser.datatype
+
+import com.smallhacker.disbrowser.util.asReverseSequence
+
+interface RangeMap<K : Comparable<K>, R : ClosedRange<K>, V : Any> {
+    operator fun get(key: K): V?
+}
+
+
+interface MutableRangeMap<K : Comparable<K>, R : ClosedRange<K>, V: Any> : RangeMap<K, R, V> {
+    operator fun set(keyRange: R, value: V): RangeMap<K, R, V>
+}
+
+class NaiveRangeMap<K : Comparable<K>, R : ClosedRange<K>, V: Any> : MutableRangeMap<K, R, V> {
+    private val entries = ArrayList<Pair<R, V>>()
+
+    override fun get(key: K) = entries
+            .asReverseSequence()
+            .filter { it.first.contains(key) }
+            .map { it.second }
+            .firstOrNull()
+
+    override fun set(keyRange: R, value: V): RangeMap<K, R, V> {
+        entries += keyRange to value
+        return this
+    }
+}

src/main/java/com/smallhacker/disbrowser/disassembler/Disassembler.kt

@@ -29,7 +29,8 @@ object Disassembler {
             metadata[ins.address]?.flags?.forEach { flag ->
                 if (flag is JmpIndirectLongInterleavedTable) {
                     if (global) {
-                        flag.readTable(state.data)
+                        flag.readTable(state.memory)
+                                .filterNotNull()
                                 .map { ins.postState.copy(address = it) }
                                 .forEach { tryAdd(it) }
                     }
@@ -41,6 +42,7 @@ object Disassembler {
                 } else if (flag is JslTableRoutine) {
                     if (global) {
                         flag.readTable(ins.postState)
+                                .filterNotNull()
                                 .map { ins.postState.copy(address = it) }
                                 .forEach { tryAdd(it) }
                     }
@@ -162,10 +164,14 @@ object Disassembler {
     }
 
     private fun disassembleInstruction(state: State): Instruction {
-        val pc = state.address.pc
+        val opcodeValue = state.memory[state.address] ?: return unreadableInstruction(state)
-        val opcode = Opcode.opcode(state.data[pc])
+        val opcode = Opcode.opcode(opcodeValue)
         val length = opcode.mode.instructionLength(state) ?: 1u
-        val bytes = state.data.range(pc, length)
+        val bytes = state.memory.range(state.address.value.toUInt(), length).validate()
+            ?: return unreadableInstruction(state)
         return Instruction(bytes, opcode, state)
     }
+
+    private fun unreadableInstruction(state: State) =
+            Instruction(EmptyMemorySpace, Opcode.UNKNOWN_OPCODE, state)
 }

src/main/java/com/smallhacker/disbrowser/util/misc.kt

@@ -30,6 +30,17 @@ fun joinBytes(vararg bytes: UByte) = bytes
         .mapIndexed { index, v -> v.toUInt() shl (index * 8) }
         .reduce { a, b -> a or b }
 
+fun joinNullableBytes(vararg bytes: UByte?): UInt? {
+    if (bytes.any { it == null }) {
+        return null
+    }
+
+    return bytes
+            .asSequence()
+            .mapIndexed { index, v -> v!!.toUInt() shl (index * 8) }
+            .reduce { a, b -> a or b }
+}
+
 inline class UInt24(private val data: UInt) {
     fun toUInt() = data and 0x00FF_FFFFu
     fun toUShort() = toUInt().toUShort()
@@ -43,7 +54,7 @@ inline class UInt24(private val data: UInt) {
     infix fun or(v: UInt24) = (data or v.data).toUInt24()
     infix fun or(v: UInt) = (data or v).toUInt24()
     infix fun shl(v: Int) = (data shl v).toUInt24()
-    infix fun shr(v: Int)= (toUInt() shr v).toUInt24()
+    infix fun shr(v: Int) = (toUInt() shr v).toUInt24()
 
     operator fun plus(v: UInt24) = (toUInt() + v.toUInt()).toUInt24()
     operator fun plus(v: UInt) = (toUInt() + v).toUInt24()
@@ -61,3 +72,6 @@ fun UByte.toUInt24() = this.toUInt().toUInt24()
 fun Int.toUInt24() = this.toUInt().toUInt24()
 fun Short.toUInt24() = this.toUInt().toUInt24()
 fun Byte.toUInt24() = this.toUInt().toUInt24()
+
+fun <T> List<T>.asReverseSequence(): Sequence<T> =
+        ((size - 1) downTo 0).asSequence().map { this[it] }