Don't use data object for non-primitive scalars

Fixes #1041

Author: bjorn3

src/constant.rs

@@ -1,16 +1,13 @@
 //! Handling of `static`s, `const`s and promoted allocations
 
-use rustc_span::DUMMY_SP;
-
-use rustc_ast::Mutability;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_errors::ErrorReported;
 use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrFlags;
 use rustc_middle::mir::interpret::{
- alloc_range, read_target_uint, AllocId, Allocation, ConstValue, ErrorHandled, GlobalAlloc,
- Scalar,
+ read_target_uint, AllocId, Allocation, ConstValue, ErrorHandled, GlobalAlloc, Scalar,
 };
 use rustc_middle::ty::ConstKind;
+use rustc_span::DUMMY_SP;
 
 use cranelift_codegen::ir::GlobalValueData;
 use cranelift_module::*;
@@ -171,65 +168,74 @@ pub(crate) fn codegen_const_value<'tcx>(
  }
 
  match const_val {
- ConstValue::Scalar(x) => {
- if fx.clif_type(layout.ty).is_none() {
- let (size, align) = (layout.size, layout.align.pref);
- let mut alloc = Allocation::from_bytes(
- std::iter::repeat(0).take(size.bytes_usize()).collect::<Vec<u8>>(),
- align,
- Mutability::Not,
- );
- alloc.write_scalar(fx, alloc_range(Size::ZERO, size), x.into()).unwrap();
- let alloc = fx.tcx.intern_const_alloc(alloc);
- return CValue::by_ref(pointer_for_allocation(fx, alloc), layout);
- }
-
- match x {
- Scalar::Int(int) => CValue::const_val(fx, layout, int),
- Scalar::Ptr(ptr) => {
- let alloc_kind = fx.tcx.get_global_alloc(ptr.alloc_id);
- let base_addr = match alloc_kind {
- Some(GlobalAlloc::Memory(alloc)) => {
- let data_id = data_id_for_alloc_id(
- &mut fx.constants_cx,
- fx.module,
- ptr.alloc_id,
- alloc.mutability,
- );
- let local_data_id =
- fx.module.declare_data_in_func(data_id, &mut fx.bcx.func);
- if fx.clif_comments.enabled() {
- fx.add_comment(local_data_id, format!("{:?}", ptr.alloc_id));
- }
- fx.bcx.ins().global_value(fx.pointer_type, local_data_id)
- }
- Some(GlobalAlloc::Function(instance)) => {
- let func_id = crate::abi::import_function(fx.tcx, fx.module, instance);
- let local_func_id =
- fx.module.declare_func_in_func(func_id, &mut fx.bcx.func);
- fx.bcx.ins().func_addr(fx.pointer_type, local_func_id)
- }
- Some(GlobalAlloc::Static(def_id)) => {
- assert!(fx.tcx.is_static(def_id));
- let data_id = data_id_for_static(fx.tcx, fx.module, def_id, false);
- let local_data_id =
- fx.module.declare_data_in_func(data_id, &mut fx.bcx.func);
- if fx.clif_comments.enabled() {
- fx.add_comment(local_data_id, format!("{:?}", def_id));
- }
- fx.bcx.ins().global_value(fx.pointer_type, local_data_id)
+ ConstValue::Scalar(x) => match x {
+ Scalar::Int(int) => {
+ if fx.clif_type(layout.ty).is_some() {
+ return CValue::const_val(fx, layout, int);
+ } else {
+ let raw_val = int.to_bits(int.size()).unwrap();
+ let val = match int.size().bytes() {
+ 1 => fx.bcx.ins().iconst(types::I8, raw_val as i64),
+ 2 => fx.bcx.ins().iconst(types::I16, raw_val as i64),
+ 4 => fx.bcx.ins().iconst(types::I32, raw_val as i64),
+ 8 => fx.bcx.ins().iconst(types::I64, raw_val as i64),
+ 16 => {
+ let lsb = fx.bcx.ins().iconst(types::I64, raw_val as u64 as i64);
+ let msb =
+ fx.bcx.ins().iconst(types::I64, (raw_val >> 64) as u64 as i64);
+ fx.bcx.ins().iconcat(lsb, msb)
  }
- None => bug!("missing allocation {:?}", ptr.alloc_id),
- };
- let val = if ptr.offset.bytes() != 0 {
- fx.bcx.ins().iadd_imm(base_addr, i64::try_from(ptr.offset.bytes()).unwrap())
- } else {
- base_addr
+ _ => unreachable!(),
  };
- CValue::by_val(val, layout)
+
+ let place = CPlace::new_stack_slot(fx, layout);
+ place.to_ptr().store(fx, val, MemFlags::trusted());
+ place.to_cvalue(fx)
  }
  }
- }
+ Scalar::Ptr(ptr) => {
+ let alloc_kind = fx.tcx.get_global_alloc(ptr.alloc_id);
+ let base_addr = match alloc_kind {
+ Some(GlobalAlloc::Memory(alloc)) => {
+ let data_id = data_id_for_alloc_id(
+ &mut fx.constants_cx,
+ fx.module,
+ ptr.alloc_id,
+ alloc.mutability,
+ );
+ let local_data_id =
+ fx.module.declare_data_in_func(data_id, &mut fx.bcx.func);
+ if fx.clif_comments.enabled() {
+ fx.add_comment(local_data_id, format!("{:?}", ptr.alloc_id));
+ }
+ fx.bcx.ins().global_value(fx.pointer_type, local_data_id)
+ }
+ Some(GlobalAlloc::Function(instance)) => {
+ let func_id = crate::abi::import_function(fx.tcx, fx.module, instance);
+ let local_func_id =
+ fx.module.declare_func_in_func(func_id, &mut fx.bcx.func);
+ fx.bcx.ins().func_addr(fx.pointer_type, local_func_id)
+ }
+ Some(GlobalAlloc::Static(def_id)) => {
+ assert!(fx.tcx.is_static(def_id));
+ let data_id = data_id_for_static(fx.tcx, fx.module, def_id, false);
+ let local_data_id =
+ fx.module.declare_data_in_func(data_id, &mut fx.bcx.func);
+ if fx.clif_comments.enabled() {
+ fx.add_comment(local_data_id, format!("{:?}", def_id));
+ }
+ fx.bcx.ins().global_value(fx.pointer_type, local_data_id)
+ }
+ None => bug!("missing allocation {:?}", ptr.alloc_id),
+ };
+ let val = if ptr.offset.bytes() != 0 {
+ fx.bcx.ins().iadd_imm(base_addr, i64::try_from(ptr.offset.bytes()).unwrap())
+ } else {
+ base_addr
+ };
+ CValue::by_val(val, layout)
+ }
+ },
  ConstValue::ByRef { alloc, offset } => CValue::by_ref(
  pointer_for_allocation(fx, alloc)
  .offset_i64(fx, i64::try_from(offset.bytes()).unwrap()),