Super exp!

Bread-Experts-Group · Apr 19, 2024 · ae2932e · ae2932e
1 parent 650f67b
commit ae2932e
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Showing 3 changed files with 75 additions and 34 deletions.
diff --git a/src/main/kotlin/breadmod/util/riscv32/Register.kt b/src/main/kotlin/breadmod/util/riscv32/Register.kt
@@ -6,7 +6,7 @@ package breadmod.util.riscv32
  * @author Miko Elbrecht
  * @see 1.0.0
  */
-class Register(private val lock: Int? = null) {
+class Register(private val lock: Int? = null, val saver: RegisterSaver) {
     var storedValue: Int = 0
         get() = lock ?: field
         internal set

diff --git a/src/main/kotlin/breadmod/util/riscv32/RegisterSaver.kt b/src/main/kotlin/breadmod/util/riscv32/RegisterSaver.kt
@@ -0,0 +1,7 @@
+package breadmod.util.riscv32
+
+enum class RegisterSaver {
+    CALLEE,
+    CALLER,
+    NONE
+}
diff --git a/src/main/kotlin/breadmod/util/riscv32/VirtualProcessor.kt b/src/main/kotlin/breadmod/util/riscv32/VirtualProcessor.kt
@@ -12,41 +12,75 @@ package breadmod.util.riscv32
  */
 class VirtualProcessor {
     val registers = listOf(
-        Register(0), // zero
-        Register(), // return address (ra)
-        Register(), // stack pointer (sp)
-        Register(), // global pointer (gp)
-        Register(), // thread pointer (tp)
-        Register(), // temporary/alternate return (t0)
-        Register(), // temporary (t1)
-        Register(), // temporary (t2)
-        Register(), // saved register/frame pointer (s0/fp)
-        Register(), // saved register (s1)
-        Register(), // function arguments/return values (a0)
-        Register(), // ditto (a1)
-        Register(), // function arguments (a2)
-        Register(), // ditto (a3)
-        Register(), // ditto (a4)
-        Register(), // ditto (a5)
-        Register(), // ditto (a6)
-        Register(), // ditto (a7)
-        Register(), // saved register (s2)
-        Register(), // ditto (s3)
-        Register(), // ditto (s4)
-        Register(), // ditto (s5)
-        Register(), // ditto (s6)
-        Register(), // ditto (s7)
-        Register(), // ditto (s8)
-        Register(), // ditto (s9)
-        Register(), // ditto (s10)
-        Register(), // ditto (s11)
-        Register(), // temporary (t3)
-        Register(), // ditto (t4)
-        Register(), // ditto (t5)
-        Register(), // ditto (t6)
+        Register(0, RegisterSaver.NONE), // zero
+        Register(saver = RegisterSaver.CALLER), // return address (ra)
+        Register(saver = RegisterSaver.CALLEE), // stack pointer (sp)
+        Register(saver = RegisterSaver.NONE), // global pointer (gp)
+        Register(saver = RegisterSaver.NONE), // thread pointer (tp)
+        Register(saver = RegisterSaver.CALLER), // temporary/alternate return (t0)
+        Register(saver = RegisterSaver.CALLER), // temporary (t1)
+        Register(saver = RegisterSaver.CALLER), // temporary (t2)
+        Register(saver = RegisterSaver.CALLEE), // saved register/frame pointer (s0/fp)
+        Register(saver = RegisterSaver.CALLEE), // saved register (s1)
+        Register(saver = RegisterSaver.CALLER), // function arguments/return values (a0)
+        Register(saver = RegisterSaver.CALLER), // ditto (a1)
+        Register(saver = RegisterSaver.CALLER), // function arguments (a2)
+        Register(saver = RegisterSaver.CALLER), // ditto (a3)
+        Register(saver = RegisterSaver.CALLER), // ditto (a4)
+        Register(saver = RegisterSaver.CALLER), // ditto (a5)
+        Register(saver = RegisterSaver.CALLER), // ditto (a6)
+        Register(saver = RegisterSaver.CALLER), // ditto (a7)
+        Register(saver = RegisterSaver.CALLEE), // saved register (s2)
+        Register(saver = RegisterSaver.CALLEE), // ditto (s3)
+        Register(saver = RegisterSaver.CALLEE), // ditto (s4)
+        Register(saver = RegisterSaver.CALLEE), // ditto (s5)
+        Register(saver = RegisterSaver.CALLEE), // ditto (s6)
+        Register(saver = RegisterSaver.CALLEE), // ditto (s7)
+        Register(saver = RegisterSaver.CALLEE), // ditto (s8)
+        Register(saver = RegisterSaver.CALLEE), // ditto (s9)
+        Register(saver = RegisterSaver.CALLEE), // ditto (s10)
+        Register(saver = RegisterSaver.CALLEE), // ditto (s11)
+        Register(saver = RegisterSaver.CALLER), // temporary (t3)
+        Register(saver = RegisterSaver.CALLER), // ditto (t4)
+        Register(saver = RegisterSaver.CALLER), // ditto (t5)
+        Register(saver = RegisterSaver.CALLER), // ditto (t6)
     )
 
     fun decodeInstruction(instruction: Int) {
-        val opcode = instruction and 0xFFFFFF
+
+    }
+
+    abstract class InstructionFormat(open val instruction: Int) {
+        abstract fun process(forCpu: VirtualProcessor)
+    }
+
+    /**
+     * R-type [instruction format](https://riscv.org/wp-content/uploads/2017/05/riscv-spec-v2.2.pdf#section.2.2)
+     * @author Miko Elbrecht
+     * @since 1.0.0
+     */
+    class RegisterRegisterInstruction(override val instruction: Int): InstructionFormat(instruction) {
+        constructor(
+            opcode: Int,
+            destinationRegister1: Int,
+            opcodeExtension3B: Int,
+            sourceRegister1: Int,
+            sourceRegister2: Int,
+            opcodeExtension7B: Int
+        ) : this(
+            opcode or destinationRegister1 or opcodeExtension3B or
+            sourceRegister1 or sourceRegister2 or opcodeExtension7B
+        )
+
+        val opcode: Int = instruction and 0xFFFFFF
+        val destinationRegister1: Int = (instruction and 0xFFFFF) shr 7 // one bit remaining
+        val opcodeExtension3B: Int = 0
+        val sourceRegister1: Int = 0
+        val sourceRegister2: Int = 0
+        val opcodeExtension7B: Int = 0
+
+        override fun process(forCpu: VirtualProcessor) {
+            TODO("Not yet implemented")
+        }
     }
 }