remove is_packed() method and use the layout to determine if a type should be evaluated as a const vector

Author: Jamesbarford

compiler/rustc_codegen_ssa/src/mir/operand.rs

@@ -639,12 +639,21 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                 let constant_ty = constant.ty();
                 // Make sure that constant SIMD vectors are passed as immediates.
                 // This is needed for some intrinsics.
-                if constant_ty.is_simd() && !constant_ty.is_packed() {
-                    let (llval, ty) = self.immediate_const_vector(bx, constant);
-                    OperandRef { val: OperandValue::Immediate(llval), layout: bx.layout_of(ty) }
+                return if constant_ty.is_simd() {
+                    let layout = bx.layout_of(constant_ty);
+                    match layout.abi {
+                        Abi::Vector { .. } => {
+                            let (llval, ty) = self.immediate_const_vector(bx, constant);
+                            OperandRef {
+                                val: OperandValue::Immediate(llval),
+                                layout: bx.layout_of(ty),
+                            }
+                        }
+                        _ => self.eval_mir_constant_to_operand(bx, constant),
+                    }
                 } else {
                     self.eval_mir_constant_to_operand(bx, constant)
-                }
+                };
             }
         }
     }

compiler/rustc_middle/src/ty/sty.rs

@@ -1077,14 +1077,6 @@ impl<'tcx> Ty<'tcx> {
         }
     }
 
-    #[inline]
-    pub fn is_packed(self) -> bool {
-        match self.kind() {
-            Adt(def, _) => def.repr().packed(),
-            _ => false,
-        }
-    }
-
     pub fn sequence_element_type(self, tcx: TyCtxt<'tcx>) -> Ty<'tcx> {
         match self.kind() {
             Array(ty, _) | Slice(ty) => *ty,