support floating point parsing

calyx-frontend/src/parser.rs

@@ -293,6 +293,13 @@ impl CalyxParser {
         u64::from_str_radix(input.as_str(), 2)
             .map_err(|_| input.error("Expected binary number"))
     }
+    fn float(input: Node) -> ParseResult<f64> {
+        let float_str = input.as_str();
+        let float_val: f64 = float_str
+            .parse()
+            .map_err(|_| input.error("Expected valid floating-point number"))?;
+        Ok(float_val)
+    }
 
     fn num_lit(input: Node) -> ParseResult<BitNum> {
         let span = Self::get_span(&input);
@@ -322,6 +329,21 @@ impl CalyxParser {
                     val,
                     span
                 },
+            [bitwidth(width), float(val)] => {
+                let bit_pattern = if width == 32 {
+                    (val as f32).to_bits() as u64
+                } else if width == 64 {
+                    val.to_bits()
+                } else {
+                    return Err(input.error("Unsupported bitwidth for floating-point number"));
+                };
+                BitNum {
+                    width,
+                    num_type: NumType::Hex,
+                    val: bit_pattern,
+                    span
+                }
+            },
 
         );
 

calyx-frontend/src/syntax.pest

@@ -16,6 +16,7 @@ binary =  @{ ASCII_HEX_DIGIT+ }
 decimal = @{ ASCII_HEX_DIGIT+ }
 octal =   @{ ASCII_HEX_DIGIT+ }
 hex =     @{ ASCII_HEX_DIGIT+ }
+float =   @{ ASCII_DIGIT+ ~ "." ~ ASCII_DIGIT+ }
 
 // `$` creates a compound rule which ignores whitespace while allowing for
 // inner rules (`@` makes inner rules silent).
@@ -26,7 +27,8 @@ num_lit = ${
       ~ ( "d" ~ decimal
         | "b" ~ binary
         | "x" ~ hex
-        | "o" ~ octal )
+        | "o" ~ octal
+        | "f" ~ float)
 }
 
 char = { !"\"" ~ ANY }