Add a trapff instruction.

This is the floating point equivalent of trapif: Trap when a given
condition is in the floating-point flags.

Define Intel encodings comparable to the trapif encodings.

lib/cretonne/src/ir/instructions.rs

@@ -270,6 +270,12 @@ pub enum InstructionData {
         arg: Value,
         code: ir::TrapCode,
     },
+    FloatCondTrap {
+        opcode: Opcode,
+        cond: FloatCC,
+        arg: Value,
+        code: ir::TrapCode,
+    },
 }
 
 /// A variable list of `Value` operands used for function call arguments and passing arguments to

lib/cretonne/src/verifier/mod.rs

@@ -366,6 +366,7 @@ impl<'a> Verifier<'a> {
             Trap { .. } |
             CondTrap { .. } |
             IntCondTrap { .. } |
+            FloatCondTrap { .. } |
             NullAry { .. } => {}
         }
 

lib/cretonne/src/write.rs

@@ -429,6 +429,7 @@ pub fn write_operands(
         Trap { code, .. } => write!(w, " {}", code),
         CondTrap { arg, code, .. } => write!(w, " {}, {}", arg, code),
         IntCondTrap { cond, arg, code, .. } => write!(w, " {} {}, {}", cond, arg, code),
+        FloatCondTrap { cond, arg, code, .. } => write!(w, " {} {}, {}", cond, arg, code),
     }
 }