diff --git a/src/vm/vector_functions.hpp b/src/vm/vector_functions.hpp
index e71b178..ae902af 100644
--- a/src/vm/vector_functions.hpp
+++ b/src/vm/vector_functions.hpp
@@ -40,6 +40,7 @@
 #ifndef _VM_VECTOR_FUNCTIONS_H_
 #error __FILE__ should only be included from vector_functions.h
 #endif
+#include <boost/integer.hpp>
 #include <math.h>
 namespace softvector {
 
@@ -79,6 +80,19 @@ enum FUNCT3 {
     OPFVF = 0b101,
     OPMVX = 0b110,
 };
+template <class, typename enable = void> struct twice;
+template <> struct twice<int8_t> { using type = int16_t; };
+template <> struct twice<uint8_t> { using type = uint16_t; };
+template <> struct twice<int16_t> { using type = int32_t; };
+template <> struct twice<uint16_t> { using type = uint32_t; };
+template <> struct twice<int32_t> { using type = int64_t; };
+template <> struct twice<uint32_t> { using type = uint64_t; };
+#ifdef __SIZEOF_INT128__
+template <> struct twice<int64_t> { using type = __int128_t; };
+template <> struct twice<uint64_t> { using type = __uint128_t; };
+#endif
+template <class T> using twice_t = typename twice<T>::type; // for convenience
+
 template <typename dest_elem_t, typename src2_elem_t = dest_elem_t, typename src1_elem_t = dest_elem_t>
 std::function<dest_elem_t(src2_elem_t, src1_elem_t)> get_funct(unsigned funct6, unsigned funct3) {
     if(funct3 == OPIVV || funct3 == OPIVX || funct3 == OPIVI)
@@ -93,15 +107,13 @@ std::function<dest_elem_t(src2_elem_t, src1_elem_t)> get_funct(unsigned funct6,
             return [](src2_elem_t vs2, src1_elem_t vs1) { return std::min(vs2, static_cast<src2_elem_t>(vs1)); };
         case 0b000101: // VMIN
             return [](src2_elem_t vs2, src1_elem_t vs1) {
-                return std::min(static_cast<typename std::make_signed_t<src2_elem_t>>(vs2),
-                                static_cast<typename std::make_signed_t<src2_elem_t>>(vs1));
+                return std::min(static_cast<std::make_signed_t<src2_elem_t>>(vs2), static_cast<std::make_signed_t<src2_elem_t>>(vs1));
             };
         case 0b000110: // VMAXU
             return [](src2_elem_t vs2, src1_elem_t vs1) { return std::max(vs2, static_cast<src2_elem_t>(vs1)); };
         case 0b000111: // VMAX
             return [](src2_elem_t vs2, src1_elem_t vs1) {
-                return std::max(static_cast<typename std::make_signed_t<src2_elem_t>>(vs2),
-                                static_cast<typename std::make_signed_t<src2_elem_t>>(vs1));
+                return std::max(static_cast<std::make_signed_t<src2_elem_t>>(vs2), static_cast<std::make_signed_t<src2_elem_t>>(vs1));
             };
         case 0b001001: // VAND
             return [](src2_elem_t vs2, src1_elem_t vs1) { return vs1 & vs2; };
@@ -116,8 +128,8 @@ std::function<dest_elem_t(src2_elem_t, src1_elem_t)> get_funct(unsigned funct6,
             return [](src2_elem_t vs2, src1_elem_t vs1) { return vs2 + vs1; };
         case 0b010010: // VSBC
             return [](src2_elem_t vs2, src1_elem_t vs1) {
-                return static_cast<typename std::make_signed_t<dest_elem_t>>(static_cast<typename std::make_signed_t<src2_elem_t>>(vs2) -
-                                                                             static_cast<typename std::make_signed_t<src1_elem_t>>(vs1));
+                return static_cast<std::make_signed_t<dest_elem_t>>(static_cast<std::make_signed_t<src2_elem_t>>(vs2) -
+                                                                    static_cast<std::make_signed_t<src1_elem_t>>(vs1));
             };
         // case 0b010111: // VMERGE / VMV
         // case 0b100000: // VSADDU
@@ -132,13 +144,13 @@ std::function<dest_elem_t(src2_elem_t, src1_elem_t)> get_funct(unsigned funct6,
             return [](src2_elem_t vs2, src1_elem_t vs1) { return vs2 >> (vs1 & shift_mask<src2_elem_t>()); };
         case 0b101001: // VSRA
             return [](src2_elem_t vs2, src1_elem_t vs1) {
-                return static_cast<typename std::make_signed_t<src2_elem_t>>(vs2) >> (vs1 & shift_mask<src2_elem_t>());
+                return static_cast<std::make_signed_t<src2_elem_t>>(vs2) >> (vs1 & shift_mask<src2_elem_t>());
             };
         case 0b101100: // VNSRL
             return [](src2_elem_t vs2, src1_elem_t vs1) { return vs2 >> (vs1 & shift_mask<src2_elem_t>()); };
         case 0b101101: // VNSRA
             return [](src2_elem_t vs2, src1_elem_t vs1) {
-                return static_cast<typename std::make_signed_t<src2_elem_t>>(vs2) >> (vs1 & shift_mask<src2_elem_t>());
+                return static_cast<std::make_signed_t<src2_elem_t>>(vs2) >> (vs1 & shift_mask<src2_elem_t>());
             };
         // case 0b101110: // VNCLIPU
         // case 0b101111: // VNCLIP
@@ -149,37 +161,53 @@ std::function<dest_elem_t(src2_elem_t, src1_elem_t)> get_funct(unsigned funct6,
         }
     else if(funct3 == OPMVV || funct3 == OPMVX)
         switch(funct6) {
-        // case 0b000000: // VREDSUM
-        // case 0b000001: // VREDAND
-        // case 0b000010: // VREDOR
-        // case 0b000011: // VREDXOR
-        // case 0b000100: // VREDMINU
-        // case 0b000101: // VREDMIN
-        // case 0b000110: // VREDMAXU
-        // case 0b000111: // VREDMAX
-        // case 0b001000: // VAADDU
-        // case 0b001001: // VAADD
-        // case 0b001010: // VASUBU
-        // case 0b001011: // VASUB
-        // case 0b001110: // VSLID1EUP
-        // case 0b001111: // VSLIDE1DOWN
-        // case 0b010111: // VCOMPRESS
-        // case 0b011000: // VMANDN
-        // case 0b011001: // VMAND
-        // case 0b011010: // VMOR
-        // case 0b011011: // VMXOR
-        // case 0b011100: // VMORN
-        // case 0b011101: // VMNAND
-        // case 0b011110: // VMNOR
-        // case 0b011111: // VMXNOR
-        // case 0b100000: // VDIVU
-        // case 0b100001: // VDIV
-        // case 0b100010: // VREMU
-        // case 0b100011: // VREM
-        // case 0b100100: // VMULHU
-        // case 0b100101: // VMUL
-        // case 0b100110: // VMULHSU
-        // case 0b100111: // VMULH
+            // case 0b000000: // VREDSUM
+            // case 0b000001: // VREDAND
+            // case 0b000010: // VREDOR
+            // case 0b000011: // VREDXOR
+            // case 0b000100: // VREDMINU
+            // case 0b000101: // VREDMIN
+            // case 0b000110: // VREDMAXU
+            // case 0b000111: // VREDMAX
+            // case 0b001000: // VAADDU
+            // case 0b001001: // VAADD
+            // case 0b001010: // VASUBU
+            // case 0b001011: // VASUB
+            // case 0b001110: // VSLID1EUP
+            // case 0b001111: // VSLIDE1DOWN
+            // case 0b010111: // VCOMPRESS
+            // case 0b011000: // VMANDN
+            // case 0b011001: // VMAND
+            // case 0b011010: // VMOR
+            // case 0b011011: // VMXOR
+            // case 0b011100: // VMORN
+            // case 0b011101: // VMNAND
+            // case 0b011110: // VMNOR
+            // case 0b011111: // VMXNOR
+            // case 0b100000: // VDIVU
+            // case 0b100001: // VDIV
+            // case 0b100010: // VREMU
+            // case 0b100011: // VREM
+        case 0b100100: // VMULHU
+            return [](src2_elem_t vs2, src1_elem_t vs1) {
+                return (static_cast<twice_t<src2_elem_t>>(vs2) * static_cast<twice_t<src2_elem_t>>(vs1)) >> sizeof(dest_elem_t) * 8;
+            };
+        case 0b100101: // VMUL
+            return [](src2_elem_t vs2, src1_elem_t vs1) {
+                return static_cast<std::make_signed_t<src2_elem_t>>(vs2) * static_cast<std::make_signed_t<src1_elem_t>>(vs1);
+            };
+        case 0b100110: // VMULHSU
+            return [](src2_elem_t vs2, src1_elem_t vs1) {
+                return (static_cast<twice_t<std::make_signed_t<src2_elem_t>>>(static_cast<std::make_signed_t<src2_elem_t>>(vs2)) *
+                        static_cast<twice_t<src2_elem_t>>(vs1)) >>
+                       sizeof(dest_elem_t) * 8;
+            };
+        case 0b100111: // VMULH
+            return [](src2_elem_t vs2, src1_elem_t vs1) {
+                return (static_cast<twice_t<std::make_signed_t<src2_elem_t>>>(static_cast<std::make_signed_t<src2_elem_t>>(vs2)) *
+                        static_cast<twice_t<std::make_signed_t<src2_elem_t>>>(static_cast<std::make_signed_t<src1_elem_t>>(vs1))) >>
+                       sizeof(dest_elem_t) * 8;
+            };
         // case 0b101001: // VMADD
         // case 0b101011: // VNMSUB
         // case 0b101101: // VMACC
@@ -188,29 +216,29 @@ std::function<dest_elem_t(src2_elem_t, src1_elem_t)> get_funct(unsigned funct6,
             return [](src2_elem_t vs2, src1_elem_t vs1) { return vs2 + vs1; };
         case 0b110001: // VWADD
             return [](src2_elem_t vs2, src1_elem_t vs1) {
-                return static_cast<typename std::make_signed_t<dest_elem_t>>(static_cast<typename std::make_signed_t<src2_elem_t>>(vs2) +
-                                                                             static_cast<typename std::make_signed_t<src1_elem_t>>(vs1));
+                return static_cast<std::make_signed_t<dest_elem_t>>(static_cast<std::make_signed_t<src2_elem_t>>(vs2) +
+                                                                    static_cast<std::make_signed_t<src1_elem_t>>(vs1));
             };
         case 0b110010: // VWSUBU
             return [](src2_elem_t vs2, src1_elem_t vs1) { return vs2 - vs1; };
         case 0b110011: // VWSUB
             return [](src2_elem_t vs2, src1_elem_t vs1) {
-                return static_cast<typename std::make_signed_t<dest_elem_t>>(static_cast<typename std::make_signed_t<src2_elem_t>>(vs2) -
-                                                                             static_cast<typename std::make_signed_t<src1_elem_t>>(vs1));
+                return static_cast<std::make_signed_t<dest_elem_t>>(static_cast<std::make_signed_t<src2_elem_t>>(vs2) -
+                                                                    static_cast<std::make_signed_t<src1_elem_t>>(vs1));
             };
         case 0b110100: // VWADDU.W
             return [](src2_elem_t vs2, src1_elem_t vs1) { return vs2 + vs1; };
         case 0b110101: // VWADD.W
             return [](src2_elem_t vs2, src1_elem_t vs1) {
-                return static_cast<typename std::make_signed_t<dest_elem_t>>(static_cast<typename std::make_signed_t<src2_elem_t>>(vs2) +
-                                                                             static_cast<typename std::make_signed_t<src1_elem_t>>(vs1));
+                return static_cast<std::make_signed_t<dest_elem_t>>(static_cast<std::make_signed_t<src2_elem_t>>(vs2) +
+                                                                    static_cast<std::make_signed_t<src1_elem_t>>(vs1));
             };
         case 0b110110: // VWSUBU.W
             return [](src2_elem_t vs2, src1_elem_t vs1) { return vs2 - vs1; };
         case 0b110111: // VWSUB.W
             return [](src2_elem_t vs2, src1_elem_t vs1) {
-                return static_cast<typename std::make_signed_t<dest_elem_t>>(static_cast<typename std::make_signed_t<src2_elem_t>>(vs2) -
-                                                                             static_cast<typename std::make_signed_t<src1_elem_t>>(vs1));
+                return static_cast<std::make_signed_t<dest_elem_t>>(static_cast<std::make_signed_t<src2_elem_t>>(vs2) -
+                                                                    static_cast<std::make_signed_t<src1_elem_t>>(vs1));
             };
             // case 0b111000: // VWMULU
             // case 0b111010: // VWMULSU
@@ -241,7 +269,8 @@ void vector_vector_op(uint8_t* V, unsigned funct6, unsigned funct3, uint64_t vl,
         for(unsigned idx = vstart; idx < std::min(elem_count, vl); idx++) {
             bool mask_active = vm ? 1 : mask_reg[idx];
             if(mask_active) {
-                vd_view[idx] = fn(vs2_view[idx], vs1_view[idx]);
+                auto res = fn(vs2_view[idx], vs1_view[idx]);
+                vd_view[idx] = res;
             } else {
                 vd_view[idx] = vtype.vma() ? vd_view[idx] : vd_view[idx];
             }
@@ -302,20 +331,6 @@ void vector_imm_op(uint8_t* V, unsigned funct6, unsigned funct3, uint64_t vl, ui
     }
     return;
 }
-template <typename elem_t> std::function<bool(elem_t, elem_t, elem_t)> get_carry_mask_funct(unsigned funct) {
-    switch(funct) {
-    case 0b010001: // VMADC
-        return [](elem_t vs2, elem_t vs1, elem_t carry) {
-            return static_cast<elem_t>(vs2 + vs1 + carry) < std::max(vs1, vs2) || static_cast<elem_t>(vs2 + vs1) < std::max(vs1, vs2);
-        };
-    case 0b010011: // VMSBC
-        return [](elem_t vs2, elem_t vs1, elem_t carry) {
-            return vs2 < static_cast<elem_t>(vs1 + carry) || (vs1 == std::numeric_limits<elem_t>::max() && carry);
-        };
-    default:
-        throw new std::runtime_error("Uknown funct in get_carry_mask_funct");
-    }
-}
 template <typename elem_t> std::function<bool(elem_t, elem_t)> get_mask_funct(unsigned funct) {
     switch(funct) {
     case 0b011000: // VMSEQ
@@ -416,7 +431,7 @@ std::function<dest_elem_t(src2_elem_t)> get_unary_fn(unsigned unary_op) {
     case 0b00111: // vsext.vf2
     case 0b00101: // vsext.vf4
     case 0b00011: // vsext.vf8
-        return [](src2_elem_t vs2) { return static_cast<typename std::make_signed_t<src2_elem_t>>(vs2); };
+        return [](src2_elem_t vs2) { return static_cast<std::make_signed_t<src2_elem_t>>(vs2); };
     case 0b00110: // vzext.vf2
     case 0b00100: // vzext.vf4
     case 0b00010: // vzext.vf8
@@ -450,6 +465,20 @@ void vector_unary_op(uint8_t* V, unsigned unary_op, uint64_t vl, uint64_t vstart
     }
     return;
 }
+template <typename elem_t> std::function<bool(elem_t, elem_t, elem_t)> get_carry_funct(unsigned funct) {
+    switch(funct) {
+    case 0b010001: // VMADC
+        return [](elem_t vs2, elem_t vs1, elem_t carry) {
+            return static_cast<elem_t>(vs2 + vs1 + carry) < std::max(vs1, vs2) || static_cast<elem_t>(vs2 + vs1) < std::max(vs1, vs2);
+        };
+    case 0b010011: // VMSBC
+        return [](elem_t vs2, elem_t vs1, elem_t carry) {
+            return vs2 < static_cast<elem_t>(vs1 + carry) || (vs1 == std::numeric_limits<elem_t>::max() && carry);
+        };
+    default:
+        throw new std::runtime_error("Uknown funct in get_carry_funct");
+    }
+}
 template <unsigned VLEN, typename elem_t>
 void carry_vector_vector_op(uint8_t* V, unsigned funct, uint64_t vl, uint64_t vstart, vtype_t vtype, bool vm, unsigned vd, unsigned vs2,
                             unsigned vs1) {
@@ -458,7 +487,7 @@ void carry_vector_vector_op(uint8_t* V, unsigned funct, uint64_t vl, uint64_t vs
     auto vs1_view = get_vreg<VLEN, elem_t>(V, vs1, elem_count);
     auto vs2_view = get_vreg<VLEN, elem_t>(V, vs2, elem_count);
     vmask_view vd_mask_view = read_vmask<VLEN>(V, elem_count, vd);
-    auto fn = get_carry_mask_funct<elem_t>(funct);
+    auto fn = get_carry_funct<elem_t>(funct);
     // elements w/ index smaller than vstart are in the prestart and get skipped
     // body is from vstart to min(elem_count, vl)
     for(unsigned idx = vstart; idx < std::min(elem_count, vl); idx++) {
@@ -482,7 +511,7 @@ void carry_vector_imm_op(uint8_t* V, unsigned funct, uint64_t vl, uint64_t vstar
     vmask_view mask_reg = read_vmask<VLEN>(V, elem_count);
     auto vs2_view = get_vreg<VLEN, elem_t>(V, vs2, elem_count);
     vmask_view vd_mask_view = read_vmask<VLEN>(V, elem_count, vd);
-    auto fn = get_carry_mask_funct<elem_t>(funct);
+    auto fn = get_carry_funct<elem_t>(funct);
     // elements w/ index smaller than vstart are in the prestart and get skipped
     // body is from vstart to min(elem_count, vl)
     for(unsigned idx = vstart; idx < std::min(elem_count, vl); idx++) {