mir: Load FatPtr constants instead of keeping them indirect.

Author: eddyb

src/librustc_trans/trans/mir/constant.rs

@@ -17,6 +17,7 @@ use trans::abi;
 use trans::common::{self, BlockAndBuilder, C_bool, C_bytes, C_floating_f64, C_integral,
                     C_str_slice, C_undef};
 use trans::consts;
+use trans::datum;
 use trans::expr;
 use trans::inline;
 use trans::type_of;
@@ -122,7 +123,18 @@ impl<'bcx, 'tcx> MirContext<'bcx, 'tcx> {
                 let d = bcx.with_block(|bcx| {
                     expr::trans(bcx, expr)
                 });
-                OperandRef::from_rvalue_datum(d.datum.to_rvalue_datum(d.bcx, "").datum)
+
+                let datum = d.datum.to_rvalue_datum(d.bcx, "").datum;
+
+                match datum.kind.mode {
+                    datum::RvalueMode::ByValue => {
+                        OperandRef {
+                            ty: datum.ty,
+                            val: OperandValue::Immediate(datum.val)
+                        }
+                    }
+                    datum::RvalueMode::ByRef => self.trans_load(bcx, datum.val, datum.ty)
+                }
             }
             mir::Literal::Value { ref value } => {
                 self.trans_constval(bcx, value, ty)

src/librustc_trans/trans/mir/operand.rs

@@ -81,16 +81,6 @@ impl<'tcx> OperandRef<'tcx> {
             _ => unreachable!()
         }
     }
-
-    pub fn from_rvalue_datum(datum: datum::Datum<'tcx, datum::Rvalue>) -> OperandRef {
-        OperandRef {
-            ty: datum.ty,
-            val: match datum.kind.mode {
-                datum::RvalueMode::ByRef => OperandValue::Ref(datum.val),
-                datum::RvalueMode::ByValue => OperandValue::Immediate(datum.val),
-            }
-        }
-    }
 }
 
 impl<'bcx, 'tcx> MirContext<'bcx, 'tcx> {