diff --git a/sim/common/rvfloats.cpp b/sim/common/rvfloats.cpp
index fd21d0c6..5e85332e 100644
--- a/sim/common/rvfloats.cpp
+++ b/sim/common/rvfloats.cpp
@@ -169,7 +169,7 @@ uint32_t rv_ftoi_s(uint32_t a, uint32_t frm, uint32_t* fflags) {
   return r;
 }
 
-uint64_t rv_ftoi_d(uint64_t a, uint32_t frm, uint32_t* fflags) {
+uint32_t rv_ftoi_d(uint64_t a, uint32_t frm, uint32_t* fflags) {
   softfloat_roundingMode = frm;
   auto r = f64_to_i32(to_float64_t(a), frm, true);
   if (fflags) { *fflags = get_fflags(); }
@@ -183,7 +183,7 @@ uint32_t rv_ftou_s(uint32_t a, uint32_t frm, uint32_t* fflags) {
   return r;
 }
 
-uint64_t rv_ftou_d(uint64_t a, uint32_t frm, uint32_t* fflags) {
+uint32_t rv_ftou_d(uint64_t a, uint32_t frm, uint32_t* fflags) {
   softfloat_roundingMode = frm;
   auto r = f64_to_ui32(to_float64_t(a), frm, true);
   if (fflags) { *fflags = get_fflags(); }
@@ -225,7 +225,7 @@ uint32_t rv_itof_s(uint32_t a, uint32_t frm, uint32_t* fflags) {
   return from_float32_t(r);
 }
 
-uint64_t rv_itof_d(uint64_t a, uint32_t frm, uint32_t* fflags) {
+uint64_t rv_itof_d(uint32_t a, uint32_t frm, uint32_t* fflags) {
   softfloat_roundingMode = frm;
   auto r = i32_to_f64(a);
   if (fflags) { *fflags = get_fflags(); }
@@ -239,7 +239,7 @@ uint32_t rv_utof_s(uint32_t a, uint32_t frm, uint32_t* fflags) {
   return from_float32_t(r);
 }
 
-uint64_t rv_utof_d(uint64_t a, uint32_t frm, uint32_t* fflags) {
+uint64_t rv_utof_d(uint32_t a, uint32_t frm, uint32_t* fflags) {
   softfloat_roundingMode = frm;
   auto r = ui32_to_f64(a);
   if (fflags) { *fflags = get_fflags(); }
@@ -274,38 +274,37 @@ uint64_t rv_lutof_d(uint64_t a, uint32_t frm, uint32_t* fflags) {
   return from_float64_t(r);
 }
 
-uint32_t rv_flt_s(uint32_t a, uint32_t b, uint32_t* fflags) {
+bool rv_flt_s(uint32_t a, uint32_t b, uint32_t* fflags) {
   auto r = f32_lt(to_float32_t(a), to_float32_t(b));
   if (fflags) { *fflags = get_fflags(); }
   return r;
 }
 
-uint64_t rv_flt_d(uint64_t a, uint64_t b, uint32_t* fflags) {
+bool rv_flt_d(uint64_t a, uint64_t b, uint32_t* fflags) {
   auto r = f64_lt(to_float64_t(a), to_float64_t(b));
   if (fflags) { *fflags = get_fflags(); }
   return r;
 }
 
-uint32_t rv_fle_s(uint32_t a, uint32_t b, uint32_t* fflags) {
+bool rv_fle_s(uint32_t a, uint32_t b, uint32_t* fflags) {
   auto r = f32_le(to_float32_t(a), to_float32_t(b));
   if (fflags) { *fflags = get_fflags(); }
   return r;
 }
 
-uint64_t rv_fle_d(uint64_t a, uint64_t b, uint32_t* fflags) {
+bool rv_fle_d(uint64_t a, uint64_t b, uint32_t* fflags) {
   auto r = f64_le(to_float64_t(a), to_float64_t(b));
   if (fflags) { *fflags = get_fflags(); }
   return r;
 }
 
-uint32_t rv_feq_s(uint32_t a, uint32_t b, uint32_t* fflags) {
-
+bool rv_feq_s(uint32_t a, uint32_t b, uint32_t* fflags) {
   auto r = f32_eq(to_float32_t(a), to_float32_t(b));
   if (fflags) { *fflags = get_fflags(); }  
   return r;
 }
 
-uint64_t rv_feq_d(uint64_t a, uint64_t b, uint32_t* fflags) {
+bool rv_feq_d(uint64_t a, uint64_t b, uint32_t* fflags) {
   auto r = f64_eq(to_float64_t(a), to_float64_t(b));
   if (fflags) { *fflags = get_fflags(); }
   return r;
diff --git a/sim/common/rvfloats.h b/sim/common/rvfloats.h
index a27caf58..4e92c007 100644
--- a/sim/common/rvfloats.h
+++ b/sim/common/rvfloats.h
@@ -33,9 +33,9 @@ uint32_t rv_fsgnj_s(uint32_t a, uint32_t b);
 uint32_t rv_fsgnjn_s(uint32_t a, uint32_t b);
 uint32_t rv_fsgnjx_s(uint32_t a, uint32_t b);
 
-uint32_t rv_flt_s(uint32_t a, uint32_t b, uint32_t* fflags);
-uint32_t rv_fle_s(uint32_t a, uint32_t b, uint32_t* fflags);
-uint32_t rv_feq_s(uint32_t a, uint32_t b, uint32_t* fflags);
+bool rv_flt_s(uint32_t a, uint32_t b, uint32_t* fflags);
+bool rv_fle_s(uint32_t a, uint32_t b, uint32_t* fflags);
+bool rv_feq_s(uint32_t a, uint32_t b, uint32_t* fflags);
 uint32_t rv_fmin_s(uint32_t a, uint32_t b, uint32_t* fflags);
 uint32_t rv_fmax_s(uint32_t a, uint32_t b, uint32_t* fflags);
 
@@ -52,12 +52,12 @@ uint64_t rv_fmsub_d(uint64_t a, uint64_t b, uint64_t c, uint32_t frm, uint32_t*
 uint64_t rv_fnmadd_d(uint64_t a, uint64_t b, uint64_t c, uint32_t frm, uint32_t* fflags);
 uint64_t rv_fnmsub_d(uint64_t a, uint64_t b, uint64_t c, uint32_t frm, uint32_t* fflags);
 
-uint64_t rv_ftoi_d(uint64_t a, uint32_t frm, uint32_t* fflags);
-uint64_t rv_ftou_d(uint64_t a, uint32_t frm, uint32_t* fflags);
+uint32_t rv_ftoi_d(uint64_t a, uint32_t frm, uint32_t* fflags);
+uint32_t rv_ftou_d(uint64_t a, uint32_t frm, uint32_t* fflags);
 uint64_t rv_ftol_d(uint64_t a, uint32_t frm, uint32_t* fflags);
 uint64_t rv_ftolu_d(uint64_t a, uint32_t frm, uint32_t* fflags);
-uint64_t rv_itof_d(uint64_t a, uint32_t frm, uint32_t* fflags);
-uint64_t rv_utof_d(uint64_t a, uint32_t frm, uint32_t* fflags);
+uint64_t rv_itof_d(uint32_t a, uint32_t frm, uint32_t* fflags);
+uint64_t rv_utof_d(uint32_t a, uint32_t frm, uint32_t* fflags);
 uint64_t rv_ltof_d(uint64_t a, uint32_t frm, uint32_t* fflags);
 uint64_t rv_lutof_d(uint64_t a, uint32_t frm, uint32_t* fflags);
 
@@ -66,9 +66,9 @@ uint64_t rv_fsgnj_d(uint64_t a, uint64_t b);
 uint64_t rv_fsgnjn_d(uint64_t a, uint64_t b);
 uint64_t rv_fsgnjx_d(uint64_t a, uint64_t b);
 
-uint64_t rv_flt_d(uint64_t a, uint64_t b, uint32_t* fflags);
-uint64_t rv_fle_d(uint64_t a, uint64_t b, uint32_t* fflags);
-uint64_t rv_feq_d(uint64_t a, uint64_t b, uint32_t* fflags);
+bool rv_flt_d(uint64_t a, uint64_t b, uint32_t* fflags);
+bool rv_fle_d(uint64_t a, uint64_t b, uint32_t* fflags);
+bool rv_feq_d(uint64_t a, uint64_t b, uint32_t* fflags);
 uint64_t rv_fmin_d(uint64_t a, uint64_t b, uint32_t* fflags);
 uint64_t rv_fmax_d(uint64_t a, uint64_t b, uint32_t* fflags);
 
diff --git a/sim/simx/decode.cpp b/sim/simx/decode.cpp
index cc4d3c83..7ab19e2f 100644
--- a/sim/simx/decode.cpp
+++ b/sim/simx/decode.cpp
@@ -444,21 +444,31 @@ std::shared_ptr<Instr> Decoder::decode(uint32_t code) const {
       switch (func7) {      
       case 0x50: // FLE.S, FLT.S, FEQ.S
       case 0x51: // FLE.D, FLT.D, FEQ.D
+        instr->setDestReg(rd, RegType::Integer);
+        instr->setSrcReg(rs1, RegType::Float);
+        instr->setSrcReg(rs2, RegType::Float);
+        break;
       case 0x60: // FCVT.W.D, FCVT.WU.D, FCVT.L.D, FCVT.LU.D
       case 0x61: // FCVT.WU.S, FCVT.W.S, FCVT.L.S, FCVT.LU.S
-      case 0x70: // FCLASS.S, FMV.X.W
-      case 0x71: // FCLASS.D, FMV.X.D        
         instr->setDestReg(rd, RegType::Integer);
         instr->setSrcReg(rs1, RegType::Float);
         instr->setSrcReg(rs2, RegType::Integer);
         break;
       case 0x68: // FCVT.S.W, FCVT.S.WU, FCVT.S.L, FCVT.S.LU
       case 0x69: // FCVT.D.W, FCVT.D.WU, FCVT.D.L, FCVT.D.LU
+        instr->setDestReg(rd, RegType::Float);
+        instr->setSrcReg(rs1, RegType::Integer);
+        instr->setSrcReg(rs2, RegType::Integer);
+        break;
+      case 0x70: // FCLASS.S, FMV.X.W
+      case 0x71: // FCLASS.D, FMV.X.D        
+        instr->setDestReg(rd, RegType::Integer);
+        instr->setSrcReg(rs1, RegType::Float);
+        break;
       case 0x78: // FMV.W.X
       case 0x79: // FMV.D.X        
         instr->setDestReg(rd, RegType::Float);
         instr->setSrcReg(rs1, RegType::Integer);
-        instr->setSrcReg(rs2, RegType::Integer);
         break;
       default:
         instr->setDestReg(rd, RegType::Float);