mips is running

contracts/MIPS.sol

@@ -57,6 +57,10 @@ contract MIPS {
         // R-type (stores rd)
         rt = m.ReadMemory(stateHash, REG_OFFSET + ((insn >> 14) & 0x7C));
         storeAddr = REG_OFFSET + ((insn >> 9) & 0x7C);
+      } else {
+        // rt is SignExtImm
+        uint32 SignExtImm = insn&0xFFFF | (insn&0x8000 != 0 ? 0xFFFF0000 : 0);
+        rt = SignExtImm;
       }
     }
 
@@ -66,7 +70,12 @@ contract MIPS {
     if (opcode >= 0x20) {
       // M[R[rs]+SignExtImm]
       uint32 SignExtImm = insn&0xFFFF | (insn&0x8000 != 0 ? 0xFFFF0000 : 0);
-      mem = m.ReadMemory(stateHash, (rs + SignExtImm) & 0xFFFFFFFC);
+      uint32 addr = (rs + SignExtImm) & 0xFFFFFFFC;
+      mem = m.ReadMemory(stateHash, addr);
+      if (opcode >= 0x28) {
+        // store
+        storeAddr = addr;
+      }
     }
 
     // execute
@@ -84,6 +93,13 @@ contract MIPS {
     uint32 opcode = insn >> 26;    // 6-bits
     uint32 func = insn & 0x3f; // 6-bits
     // TODO: deref the immed into a register
+
+    // transform ArithLogI
+    // TODO: replace with table
+    if (opcode == 8) { opcode = 0; func = 0x20; }
+    else if (opcode == 9) { opcode = 0; func = 0x21; }
+    else if (opcode == 0xc) { opcode = 0; func = 0x24; }
+
     if (opcode == 0) {
       uint32 shamt = (insn >> 6) & 0x1f;
       // R-type (ArithLog)

contracts/MIPSMemory.sol

@@ -15,9 +15,15 @@ contract MIPSMemory {
     state[stateHash][addr] = (1 << 32) | value;
   }
 
-  function WriteMemory(bytes32 stateHash, uint32 addr, uint32 val) public pure returns (bytes32) {
-    // TODO: does the stateHash mutation
+  function WriteMemory(bytes32 stateHash, uint32 addr, uint32 value) public pure returns (bytes32) {
     require(addr & 3 == 0, "write memory must be 32-bit aligned");
+    // TODO: do the real stateHash mutation
+    bytes32 newstateHash = keccak256(abi.encodePacked(stateHash));
+
+    // no proof required, this is obviously right
+    //state[newstateHash][addr] = (1 << 32) | value;
+
+    return newstateHash;
   }
 
   // needed for preimage oracle

mipsevm/main.go

@@ -124,6 +124,9 @@ func opStaticCall(pc *uint64, interpreter *vm.EVMInterpreter, scope *vm.ScopeCon
 		dat := common.BytesToHash(args[0x44:0x64]).Big().Uint64()
 		fmt.Println("HOOKED WRITE!", fmt.Sprintf("%x = %x", addr, dat))
 		ram[addr] = uint32(dat)
+
+		// pass through stateRoot
+		scope.Memory.Set(retOffset.Uint64(), retSize.Uint64(), args[0x4:0x24])
 	}
 
 	scope.Contract.Gas += returnGas
@@ -185,7 +188,7 @@ func main() {
 
 	// 0xdb7df598
 	input := []byte{0xdb, 0x7d, 0xf5, 0x98} // Steps(bytes32, uint256)
-	input = append(input, common.Hash{}.Bytes()...)
+	input = append(input, common.BigToHash(common.Big0).Bytes()...)
 	input = append(input, common.BigToHash(big.NewInt(int64(steps))).Bytes()...)
 	contract := vm.NewContract(vm.AccountRef(from), vm.AccountRef(to), common.Big0, 20000000)
 	//fmt.Println(bytecodehash, bytecode)