Add a trapif instruction.

This is a conditional trap controlled by integer CPU flags.
Compare to brif.

cranelift/docs/langref.rst

@@ -380,6 +380,7 @@ is zero.
 .. autoinst:: trap
 .. autoinst:: trapz
 .. autoinst:: trapnz
+.. autoinst:: trapif
 
 
 Function calls

cranelift/filetests/parser/tiny.cton

@@ -210,3 +210,18 @@ ebb0:
 ; nextln:     copy_special %20 -> %10
 ; nextln:     return
 ; nextln: }
+
+function %cond_traps(i32) {
+ebb0(v0: i32):
+    trapz v0, stk_ovf
+    v1 = ifcmp_imm v0, 5
+    trapif ugt v1, oob
+    return
+}
+; sameln: function %cond_traps(i32)
+; nextln: ebb0($v0: i32):
+; nextln:     trapz $v0, stk_ovf
+; nextln:     $v1 = ifcmp_imm v0, 5
+; nextln:     trapif ugt $v1, oob
+; nextln:     return
+; nextln: }

lib/cretonne/meta/base/formats.py

@@ -74,6 +74,7 @@ RegFill = InstructionFormat(
 
 Trap = InstructionFormat(trapcode)
 CondTrap = InstructionFormat(VALUE, trapcode)
+IntCondTrap = InstructionFormat(intcc, VALUE, trapcode)
 
 # Finally extract the names of global variables in this module.
 InstructionFormat.extract_names(globals())

lib/cretonne/meta/base/instructions.py

@@ -167,6 +167,15 @@ trapnz = Instruction(
         """,
         ins=(c, code), can_trap=True)
 
+Cond = Operand('Cond', intcc)
+f = Operand('f', iflags)
+
+trapif = Instruction(
+        'trapif', r"""
+        Trap when condition is true in integer CPU flags.
+        """,
+        ins=(Cond, f, code), can_trap=True)
+
 rvals = Operand('rvals', VARIABLE_ARGS, doc='return values')
 
 x_return = Instruction(

lib/cretonne/src/ir/instructions.rs

@@ -264,6 +264,12 @@ pub enum InstructionData {
         arg: Value,
         code: ir::TrapCode,
     },
+    IntCondTrap {
+        opcode: Opcode,
+        cond: IntCC,
+        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

@@ -365,6 +365,7 @@ impl<'a> Verifier<'a> {
             CopySpecial { .. } |
             Trap { .. } |
             CondTrap { .. } |
+            IntCondTrap { .. } |
             NullAry { .. } => {}
         }
 

lib/cretonne/src/write.rs

@@ -428,6 +428,7 @@ 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),
     }
 }
 

lib/reader/src/parser.rs

@@ -2348,6 +2348,21 @@ impl<'a> Parser<'a> {
                 let code = self.match_enum("expected trap code")?;
                 InstructionData::CondTrap { opcode, arg, code }
             }
+            InstructionFormat::IntCondTrap => {
+                let cond = self.match_enum("expected intcc condition code")?;
+                let arg = self.match_value("expected SSA value operand")?;
+                self.match_token(
+                    Token::Comma,
+                    "expected ',' between operands",
+                )?;
+                let code = self.match_enum("expected trap code")?;
+                InstructionData::IntCondTrap {
+                    opcode,
+                    cond,
+                    arg,
+                    code,
+                }
+            }
         };
         Ok(idata)
     }