Update code for fcvt.s.w, fcvt.s.wu, fadd and fsub

arch/inst/F/fadd.s.yaml

@@ -27,6 +27,7 @@ access:
   vu: always
 data_independent_timing: true
 operation(): |
+  check_f_ok($encoding);
   RoundingMode mode = rm_to_mode(X[rm], $encoding);
   X[fd] = f32_add(X[fs1], X[fs2], mode);
 

arch/inst/F/fcvt.s.w.yaml

@@ -34,20 +34,8 @@ access:
 data_independent_timing: false
 operation(): |
   check_f_ok($encoding);
-
-  Bits<32> int_value = X[rs1];
-
-  Bits<1> sign = int_value[31];
-
-  RoundingMode rounding_mode = rm_to_mode(rm, $encoding);
-
-  if ((int_value & 32'h7fff_ffff) == 0) {
-    X[fd] = (sign == 1) ? packToF32UI(1, 0x9E, 0) : 0;
-  } else {
-    Bits<32> absA = (sign == 1) ? -int_value : int_value;
-    X[fd] = softfloat_normRoundPackToF32( sign, 0x9C, absA, rounding_mode );
-  }
-
+  RoundingMode rounding_mode = rm_to_mode(X[rm], $encoding);
+  X[fd] = i32_to_f32(X[rs1], rounding_mode);
   mark_f_state_dirty();
 
 sail(): |

arch/inst/F/fsub.s.yaml

@@ -27,6 +27,7 @@ access:
   vu: always
 data_independent_timing: true
 operation(): |
+  check_f_ok($encoding);
   RoundingMode mode = rm_to_mode(X[rm], $encoding);
   X[fd] = f32_sub(X[fs1], X[fs2], mode);
 sail(): |

arch/isa/fp.idl

@@ -882,3 +882,22 @@ function f32_sub {
     }
   }
 }
+
+function i32_to_f32 {
+  returns U32
+  arguments
+    U32 a,
+    RoundingMode mode
+  description {
+    Converts 32-bit signed integer to 32-bit floating point
+  }
+  body {
+    # sign of integer, it is 1 when negative
+    Bits<1> sign = a[31];
+    if ((a & 0x7FFFFFFF) == 0) {
+      return (sign == 1) ? packToF32UI(1, 0x9E, 0) : packToF32UI(0, 0, 0);
+    }
+    U32 magnitude_of_A = returnMag(a);
+    return softfloat_normRoundPackToF32(sign, 0x9C, magnitude_of_A, mode);
+  }
+}