1 //! Definition of [`CValue`] and [`CPlace`]
5 use cranelift_codegen::ir::immediates::Offset32;
7 fn codegen_field<'tcx>(
8 fx: &mut FunctionCx<'_, '_, 'tcx>,
11 layout: TyAndLayout<'tcx>,
13 ) -> (Pointer, TyAndLayout<'tcx>) {
14 let field_offset = layout.fields.offset(field.index());
15 let field_layout = layout.field(&*fx, field.index());
17 let simple = |fx: &mut FunctionCx<'_, '_, '_>| {
18 (base.offset_i64(fx, i64::try_from(field_offset.bytes()).unwrap()), field_layout)
21 if let Some(extra) = extra {
22 if !field_layout.is_unsized() {
25 match field_layout.ty.kind() {
26 ty::Slice(..) | ty::Str | ty::Foreign(..) => simple(fx),
27 ty::Adt(def, _) if def.repr().packed() => {
28 assert_eq!(layout.align.abi.bytes(), 1);
32 // We have to align the offset for DST's
33 let unaligned_offset = field_offset.bytes();
34 let (_, unsized_align) =
35 crate::unsize::size_and_align_of_dst(fx, field_layout, extra);
37 let one = fx.bcx.ins().iconst(fx.pointer_type, 1);
38 let align_sub_1 = fx.bcx.ins().isub(unsized_align, one);
39 let and_lhs = fx.bcx.ins().iadd_imm(align_sub_1, unaligned_offset as i64);
40 let zero = fx.bcx.ins().iconst(fx.pointer_type, 0);
41 let and_rhs = fx.bcx.ins().isub(zero, unsized_align);
42 let offset = fx.bcx.ins().band(and_lhs, and_rhs);
44 (base.offset_value(fx, offset), field_layout)
52 fn scalar_pair_calculate_b_offset(tcx: TyCtxt<'_>, a_scalar: Scalar, b_scalar: Scalar) -> Offset32 {
53 let b_offset = a_scalar.size(&tcx).align_to(b_scalar.align(&tcx).abi);
54 Offset32::new(b_offset.bytes().try_into().unwrap())
58 #[derive(Debug, Copy, Clone)]
59 pub(crate) struct CValue<'tcx>(CValueInner, TyAndLayout<'tcx>);
61 #[derive(Debug, Copy, Clone)]
63 ByRef(Pointer, Option<Value>),
65 ByValPair(Value, Value),
68 impl<'tcx> CValue<'tcx> {
69 pub(crate) fn by_ref(ptr: Pointer, layout: TyAndLayout<'tcx>) -> CValue<'tcx> {
70 CValue(CValueInner::ByRef(ptr, None), layout)
73 pub(crate) fn by_ref_unsized(
76 layout: TyAndLayout<'tcx>,
78 CValue(CValueInner::ByRef(ptr, Some(meta)), layout)
81 pub(crate) fn by_val(value: Value, layout: TyAndLayout<'tcx>) -> CValue<'tcx> {
82 CValue(CValueInner::ByVal(value), layout)
85 pub(crate) fn by_val_pair(
88 layout: TyAndLayout<'tcx>,
90 CValue(CValueInner::ByValPair(value, extra), layout)
93 pub(crate) fn layout(&self) -> TyAndLayout<'tcx> {
98 pub(crate) fn force_stack(self, fx: &mut FunctionCx<'_, '_, 'tcx>) -> (Pointer, Option<Value>) {
101 CValueInner::ByRef(ptr, meta) => (ptr, meta),
102 CValueInner::ByVal(_) | CValueInner::ByValPair(_, _) => {
103 let cplace = CPlace::new_stack_slot(fx, layout);
104 cplace.write_cvalue(fx, self);
105 (cplace.to_ptr(), None)
110 pub(crate) fn try_to_ptr(self) -> Option<(Pointer, Option<Value>)> {
112 CValueInner::ByRef(ptr, meta) => Some((ptr, meta)),
113 CValueInner::ByVal(_) | CValueInner::ByValPair(_, _) => None,
117 /// Load a value with layout.abi of scalar
118 pub(crate) fn load_scalar(self, fx: &mut FunctionCx<'_, '_, 'tcx>) -> Value {
121 CValueInner::ByRef(ptr, None) => {
122 let clif_ty = match layout.abi {
123 Abi::Scalar(scalar) => scalar_to_clif_type(fx.tcx, scalar),
124 Abi::Vector { element, count } => scalar_to_clif_type(fx.tcx, element)
125 .by(u16::try_from(count).unwrap())
127 _ => unreachable!("{:?}", layout.ty),
129 let mut flags = MemFlags::new();
131 ptr.load(fx, clif_ty, flags)
133 CValueInner::ByVal(value) => value,
134 CValueInner::ByRef(_, Some(_)) => bug!("load_scalar for unsized value not allowed"),
135 CValueInner::ByValPair(_, _) => bug!("Please use load_scalar_pair for ByValPair"),
139 /// Load a value pair with layout.abi of scalar pair
140 pub(crate) fn load_scalar_pair(self, fx: &mut FunctionCx<'_, '_, 'tcx>) -> (Value, Value) {
143 CValueInner::ByRef(ptr, None) => {
144 let (a_scalar, b_scalar) = match layout.abi {
145 Abi::ScalarPair(a, b) => (a, b),
146 _ => unreachable!("load_scalar_pair({:?})", self),
148 let b_offset = scalar_pair_calculate_b_offset(fx.tcx, a_scalar, b_scalar);
149 let clif_ty1 = scalar_to_clif_type(fx.tcx, a_scalar);
150 let clif_ty2 = scalar_to_clif_type(fx.tcx, b_scalar);
151 let mut flags = MemFlags::new();
153 let val1 = ptr.load(fx, clif_ty1, flags);
154 let val2 = ptr.offset(fx, b_offset).load(fx, clif_ty2, flags);
157 CValueInner::ByRef(_, Some(_)) => {
158 bug!("load_scalar_pair for unsized value not allowed")
160 CValueInner::ByVal(_) => bug!("Please use load_scalar for ByVal"),
161 CValueInner::ByValPair(val1, val2) => (val1, val2),
165 pub(crate) fn value_field(
167 fx: &mut FunctionCx<'_, '_, 'tcx>,
172 CValueInner::ByVal(val) => match layout.abi {
173 Abi::Vector { element: _, count } => {
174 let count = u8::try_from(count).expect("SIMD type with more than 255 lanes???");
175 let field = u8::try_from(field.index()).unwrap();
176 assert!(field < count);
177 let lane = fx.bcx.ins().extractlane(val, field);
178 let field_layout = layout.field(&*fx, usize::from(field));
179 CValue::by_val(lane, field_layout)
181 _ => unreachable!("value_field for ByVal with abi {:?}", layout.abi),
183 CValueInner::ByValPair(val1, val2) => match layout.abi {
184 Abi::ScalarPair(_, _) => {
185 let val = match field.as_u32() {
188 _ => bug!("field should be 0 or 1"),
190 let field_layout = layout.field(&*fx, usize::from(field));
191 CValue::by_val(val, field_layout)
193 _ => unreachable!("value_field for ByValPair with abi {:?}", layout.abi),
195 CValueInner::ByRef(ptr, None) => {
196 let (field_ptr, field_layout) = codegen_field(fx, ptr, None, layout, field);
197 CValue::by_ref(field_ptr, field_layout)
199 CValueInner::ByRef(_, Some(_)) => todo!(),
203 /// Like [`CValue::value_field`] except handling ADTs containing a single array field in a way
204 /// such that you can access individual lanes.
205 pub(crate) fn value_lane(
207 fx: &mut FunctionCx<'_, '_, 'tcx>,
211 assert!(layout.ty.is_simd());
212 let (lane_count, lane_ty) = layout.ty.simd_size_and_type(fx.tcx);
213 let lane_layout = fx.layout_of(lane_ty);
214 assert!(lane_idx < lane_count);
216 CValueInner::ByVal(val) => match layout.abi {
217 Abi::Vector { element: _, count: _ } => {
218 assert!(lane_count <= u8::MAX.into(), "SIMD type with more than 255 lanes???");
219 let lane_idx = u8::try_from(lane_idx).unwrap();
220 let lane = fx.bcx.ins().extractlane(val, lane_idx);
221 CValue::by_val(lane, lane_layout)
223 _ => unreachable!("value_lane for ByVal with abi {:?}", layout.abi),
225 CValueInner::ByValPair(_, _) => unreachable!(),
226 CValueInner::ByRef(ptr, None) => {
227 let field_offset = lane_layout.size * lane_idx;
228 let field_ptr = ptr.offset_i64(fx, i64::try_from(field_offset.bytes()).unwrap());
229 CValue::by_ref(field_ptr, lane_layout)
231 CValueInner::ByRef(_, Some(_)) => unreachable!(),
235 pub(crate) fn unsize_value(self, fx: &mut FunctionCx<'_, '_, 'tcx>, dest: CPlace<'tcx>) {
236 crate::unsize::coerce_unsized_into(fx, self, dest);
239 /// If `ty` is signed, `const_val` must already be sign extended.
240 pub(crate) fn const_val(
241 fx: &mut FunctionCx<'_, '_, 'tcx>,
242 layout: TyAndLayout<'tcx>,
243 const_val: ty::ScalarInt,
245 assert_eq!(const_val.size(), layout.size, "{:#?}: {:?}", const_val, layout);
246 use cranelift_codegen::ir::immediates::{Ieee32, Ieee64};
248 let clif_ty = fx.clif_type(layout.ty).unwrap();
250 if let ty::Bool = layout.ty.kind() {
252 const_val == ty::ScalarInt::FALSE || const_val == ty::ScalarInt::TRUE,
253 "Invalid bool 0x{:032X}",
258 let val = match layout.ty.kind() {
259 ty::Uint(UintTy::U128) | ty::Int(IntTy::I128) => {
260 let const_val = const_val.to_bits(layout.size).unwrap();
261 let lsb = fx.bcx.ins().iconst(types::I64, const_val as u64 as i64);
262 let msb = fx.bcx.ins().iconst(types::I64, (const_val >> 64) as u64 as i64);
263 fx.bcx.ins().iconcat(lsb, msb)
265 ty::Bool | ty::Char | ty::Uint(_) | ty::Int(_) | ty::Ref(..) | ty::RawPtr(..) => {
266 fx.bcx.ins().iconst(clif_ty, const_val.to_bits(layout.size).unwrap() as i64)
268 ty::Float(FloatTy::F32) => {
269 fx.bcx.ins().f32const(Ieee32::with_bits(u32::try_from(const_val).unwrap()))
271 ty::Float(FloatTy::F64) => {
272 fx.bcx.ins().f64const(Ieee64::with_bits(u64::try_from(const_val).unwrap()))
275 "CValue::const_val for non bool/char/float/integer/pointer type {:?} is not allowed",
280 CValue::by_val(val, layout)
283 pub(crate) fn cast_pointer_to(self, layout: TyAndLayout<'tcx>) -> Self {
284 assert!(matches!(self.layout().ty.kind(), ty::Ref(..) | ty::RawPtr(..) | ty::FnPtr(..)));
285 assert!(matches!(layout.ty.kind(), ty::Ref(..) | ty::RawPtr(..) | ty::FnPtr(..)));
286 assert_eq!(self.layout().abi, layout.abi);
287 CValue(self.0, layout)
291 /// A place where you can write a value to or read a value from
292 #[derive(Debug, Copy, Clone)]
293 pub(crate) struct CPlace<'tcx> {
295 layout: TyAndLayout<'tcx>,
298 #[derive(Debug, Copy, Clone)]
299 pub(crate) enum CPlaceInner {
300 Var(Local, Variable),
301 VarPair(Local, Variable, Variable),
302 VarLane(Local, Variable, u8),
303 Addr(Pointer, Option<Value>),
306 impl<'tcx> CPlace<'tcx> {
307 pub(crate) fn layout(&self) -> TyAndLayout<'tcx> {
311 pub(crate) fn inner(&self) -> &CPlaceInner {
315 pub(crate) fn new_stack_slot(
316 fx: &mut FunctionCx<'_, '_, 'tcx>,
317 layout: TyAndLayout<'tcx>,
319 assert!(!layout.is_unsized());
320 if layout.size.bytes() == 0 {
322 inner: CPlaceInner::Addr(Pointer::dangling(layout.align.pref), None),
327 let stack_slot = fx.bcx.create_stack_slot(StackSlotData {
328 kind: StackSlotKind::ExplicitSlot,
329 // FIXME Don't force the size to a multiple of 16 bytes once Cranelift gets a way to
330 // specify stack slot alignment.
331 size: (u32::try_from(layout.size.bytes()).unwrap() + 15) / 16 * 16,
333 CPlace { inner: CPlaceInner::Addr(Pointer::stack_slot(stack_slot), None), layout }
336 pub(crate) fn new_var(
337 fx: &mut FunctionCx<'_, '_, 'tcx>,
339 layout: TyAndLayout<'tcx>,
341 let var = Variable::with_u32(fx.next_ssa_var);
342 fx.next_ssa_var += 1;
343 fx.bcx.declare_var(var, fx.clif_type(layout.ty).unwrap());
344 CPlace { inner: CPlaceInner::Var(local, var), layout }
347 pub(crate) fn new_var_pair(
348 fx: &mut FunctionCx<'_, '_, 'tcx>,
350 layout: TyAndLayout<'tcx>,
352 let var1 = Variable::with_u32(fx.next_ssa_var);
353 fx.next_ssa_var += 1;
354 let var2 = Variable::with_u32(fx.next_ssa_var);
355 fx.next_ssa_var += 1;
357 let (ty1, ty2) = fx.clif_pair_type(layout.ty).unwrap();
358 fx.bcx.declare_var(var1, ty1);
359 fx.bcx.declare_var(var2, ty2);
360 CPlace { inner: CPlaceInner::VarPair(local, var1, var2), layout }
363 pub(crate) fn for_ptr(ptr: Pointer, layout: TyAndLayout<'tcx>) -> CPlace<'tcx> {
364 CPlace { inner: CPlaceInner::Addr(ptr, None), layout }
367 pub(crate) fn for_ptr_with_extra(
370 layout: TyAndLayout<'tcx>,
372 CPlace { inner: CPlaceInner::Addr(ptr, Some(extra)), layout }
375 pub(crate) fn to_cvalue(self, fx: &mut FunctionCx<'_, '_, 'tcx>) -> CValue<'tcx> {
376 let layout = self.layout();
378 CPlaceInner::Var(_local, var) => {
379 let val = fx.bcx.use_var(var);
380 //fx.bcx.set_val_label(val, cranelift_codegen::ir::ValueLabel::new(var.index()));
381 CValue::by_val(val, layout)
383 CPlaceInner::VarPair(_local, var1, var2) => {
384 let val1 = fx.bcx.use_var(var1);
385 //fx.bcx.set_val_label(val1, cranelift_codegen::ir::ValueLabel::new(var1.index()));
386 let val2 = fx.bcx.use_var(var2);
387 //fx.bcx.set_val_label(val2, cranelift_codegen::ir::ValueLabel::new(var2.index()));
388 CValue::by_val_pair(val1, val2, layout)
390 CPlaceInner::VarLane(_local, var, lane) => {
391 let val = fx.bcx.use_var(var);
392 //fx.bcx.set_val_label(val, cranelift_codegen::ir::ValueLabel::new(var.index()));
393 let val = fx.bcx.ins().extractlane(val, lane);
394 CValue::by_val(val, layout)
396 CPlaceInner::Addr(ptr, extra) => {
397 if let Some(extra) = extra {
398 CValue::by_ref_unsized(ptr, extra, layout)
400 CValue::by_ref(ptr, layout)
406 pub(crate) fn to_ptr(self) -> Pointer {
407 match self.to_ptr_maybe_unsized() {
409 (_, Some(_)) => bug!("Expected sized cplace, found {:?}", self),
413 pub(crate) fn to_ptr_maybe_unsized(self) -> (Pointer, Option<Value>) {
415 CPlaceInner::Addr(ptr, extra) => (ptr, extra),
416 CPlaceInner::Var(_, _)
417 | CPlaceInner::VarPair(_, _, _)
418 | CPlaceInner::VarLane(_, _, _) => bug!("Expected CPlace::Addr, found {:?}", self),
422 pub(crate) fn write_cvalue(self, fx: &mut FunctionCx<'_, '_, 'tcx>, from: CValue<'tcx>) {
423 assert_assignable(fx, from.layout().ty, self.layout().ty);
425 self.write_cvalue_maybe_transmute(fx, from, "write_cvalue");
428 pub(crate) fn write_cvalue_transmute(
430 fx: &mut FunctionCx<'_, '_, 'tcx>,
433 self.write_cvalue_maybe_transmute(fx, from, "write_cvalue_transmute");
436 fn write_cvalue_maybe_transmute(
438 fx: &mut FunctionCx<'_, '_, 'tcx>,
440 method: &'static str,
442 fn transmute_value<'tcx>(
443 fx: &mut FunctionCx<'_, '_, 'tcx>,
448 let src_ty = fx.bcx.func.dfg.value_type(data);
452 "write_cvalue_transmute: {:?} -> {:?}",
456 let data = match (src_ty, dst_ty) {
457 (_, _) if src_ty == dst_ty => data,
459 // This is a `write_cvalue_transmute`.
460 (types::I32, types::F32)
461 | (types::F32, types::I32)
462 | (types::I64, types::F64)
463 | (types::F64, types::I64) => fx.bcx.ins().bitcast(dst_ty, data),
464 _ if src_ty.is_vector() && dst_ty.is_vector() => {
465 fx.bcx.ins().raw_bitcast(dst_ty, data)
467 _ if src_ty.is_vector() || dst_ty.is_vector() => {
468 // FIXME do something more efficient for transmutes between vectors and integers.
469 let stack_slot = fx.bcx.create_stack_slot(StackSlotData {
470 kind: StackSlotKind::ExplicitSlot,
471 // FIXME Don't force the size to a multiple of 16 bytes once Cranelift gets a way to
472 // specify stack slot alignment.
473 size: (src_ty.bytes() + 15) / 16 * 16,
475 let ptr = Pointer::stack_slot(stack_slot);
476 ptr.store(fx, data, MemFlags::trusted());
477 ptr.load(fx, dst_ty, MemFlags::trusted())
480 // `CValue`s should never contain SSA-only types, so if you ended
481 // up here having seen an error like `B1 -> I8`, then before
482 // calling `write_cvalue` you need to add a `bint` instruction.
483 _ => unreachable!("write_cvalue_transmute: {:?} -> {:?}", src_ty, dst_ty),
485 //fx.bcx.set_val_label(data, cranelift_codegen::ir::ValueLabel::new(var.index()));
486 fx.bcx.def_var(var, data);
489 assert_eq!(self.layout().size, from.layout().size);
491 if fx.clif_comments.enabled() {
492 use cranelift_codegen::cursor::{Cursor, CursorPosition};
493 let cur_block = match fx.bcx.cursor().position() {
494 CursorPosition::After(block) => block,
498 fx.bcx.func.layout.last_inst(cur_block).unwrap(),
500 "{}: {:?}: {:?} <- {:?}: {:?}",
510 let dst_layout = self.layout();
511 let to_ptr = match self.inner {
512 CPlaceInner::Var(_local, var) => {
513 if let ty::Array(element, len) = dst_layout.ty.kind() {
514 // Can only happen for vector types
516 u16::try_from(len.eval_usize(fx.tcx, ParamEnv::reveal_all())).unwrap();
517 let vector_ty = fx.clif_type(*element).unwrap().by(len).unwrap();
519 let data = match from.0 {
520 CValueInner::ByRef(ptr, None) => {
521 let mut flags = MemFlags::new();
523 ptr.load(fx, vector_ty, flags)
525 CValueInner::ByVal(_)
526 | CValueInner::ByValPair(_, _)
527 | CValueInner::ByRef(_, Some(_)) => bug!("array should be ByRef"),
530 fx.bcx.def_var(var, data);
533 let data = CValue(from.0, dst_layout).load_scalar(fx);
534 let dst_ty = fx.clif_type(self.layout().ty).unwrap();
535 transmute_value(fx, var, data, dst_ty);
538 CPlaceInner::VarPair(_local, var1, var2) => {
539 let (data1, data2) = CValue(from.0, dst_layout).load_scalar_pair(fx);
540 let (dst_ty1, dst_ty2) = fx.clif_pair_type(self.layout().ty).unwrap();
541 transmute_value(fx, var1, data1, dst_ty1);
542 transmute_value(fx, var2, data2, dst_ty2);
545 CPlaceInner::VarLane(_local, var, lane) => {
546 let data = from.load_scalar(fx);
548 // First get the old vector
549 let vector = fx.bcx.use_var(var);
550 //fx.bcx.set_val_label(vector, cranelift_codegen::ir::ValueLabel::new(var.index()));
552 // Next insert the written lane into the vector
553 let vector = fx.bcx.ins().insertlane(vector, data, lane);
555 // Finally write the new vector
556 //fx.bcx.set_val_label(vector, cranelift_codegen::ir::ValueLabel::new(var.index()));
557 fx.bcx.def_var(var, vector);
561 CPlaceInner::Addr(ptr, None) => {
562 if dst_layout.size == Size::ZERO || dst_layout.abi == Abi::Uninhabited {
567 CPlaceInner::Addr(_, Some(_)) => bug!("Can't write value to unsized place {:?}", self),
570 let mut flags = MemFlags::new();
572 match from.layout().abi {
573 // FIXME make Abi::Vector work too
575 let val = from.load_scalar(fx);
576 to_ptr.store(fx, val, flags);
579 Abi::ScalarPair(a_scalar, b_scalar) => {
580 let (value, extra) = from.load_scalar_pair(fx);
581 let b_offset = scalar_pair_calculate_b_offset(fx.tcx, a_scalar, b_scalar);
582 to_ptr.store(fx, value, flags);
583 to_ptr.offset(fx, b_offset).store(fx, extra, flags);
590 CValueInner::ByVal(val) => {
591 to_ptr.store(fx, val, flags);
593 CValueInner::ByValPair(_, _) => {
594 bug!("Non ScalarPair abi {:?} for ByValPair CValue", dst_layout.abi);
596 CValueInner::ByRef(from_ptr, None) => {
597 let from_addr = from_ptr.get_addr(fx);
598 let to_addr = to_ptr.get_addr(fx);
599 let src_layout = from.1;
600 let size = dst_layout.size.bytes();
601 let src_align = src_layout.align.abi.bytes() as u8;
602 let dst_align = dst_layout.align.abi.bytes() as u8;
603 fx.bcx.emit_small_memory_copy(
614 CValueInner::ByRef(_, Some(_)) => todo!(),
618 pub(crate) fn place_field(
620 fx: &mut FunctionCx<'_, '_, 'tcx>,
623 let layout = self.layout();
626 CPlaceInner::Var(local, var) => match layout.ty.kind() {
628 // Can only happen for vector types
630 inner: CPlaceInner::VarLane(local, var, field.as_u32().try_into().unwrap()),
631 layout: layout.field(fx, field.as_u32().try_into().unwrap()),
634 ty::Adt(adt_def, substs) if layout.ty.is_simd() => {
635 let f0_ty = adt_def.non_enum_variant().fields[0].ty(fx.tcx, substs);
639 assert_eq!(field.as_u32(), 0);
641 inner: CPlaceInner::Var(local, var),
642 layout: layout.field(fx, field.as_u32().try_into().unwrap()),
647 inner: CPlaceInner::VarLane(
650 field.as_u32().try_into().unwrap(),
652 layout: layout.field(fx, field.as_u32().try_into().unwrap()),
659 CPlaceInner::VarPair(local, var1, var2) => {
660 let layout = layout.field(&*fx, field.index());
662 match field.as_u32() {
663 0 => return CPlace { inner: CPlaceInner::Var(local, var1), layout },
664 1 => return CPlace { inner: CPlaceInner::Var(local, var2), layout },
665 _ => unreachable!("field should be 0 or 1"),
671 let (base, extra) = self.to_ptr_maybe_unsized();
673 let (field_ptr, field_layout) = codegen_field(fx, base, extra, layout, field);
674 if field_layout.is_unsized() {
675 if let ty::Foreign(_) = field_layout.ty.kind() {
676 assert!(extra.is_none());
677 CPlace::for_ptr(field_ptr, field_layout)
679 CPlace::for_ptr_with_extra(field_ptr, extra.unwrap(), field_layout)
682 CPlace::for_ptr(field_ptr, field_layout)
686 /// Like [`CPlace::place_field`] except handling ADTs containing a single array field in a way
687 /// such that you can access individual lanes.
688 pub(crate) fn place_lane(
690 fx: &mut FunctionCx<'_, '_, 'tcx>,
693 let layout = self.layout();
694 assert!(layout.ty.is_simd());
695 let (lane_count, lane_ty) = layout.ty.simd_size_and_type(fx.tcx);
696 let lane_layout = fx.layout_of(lane_ty);
697 assert!(lane_idx < lane_count);
700 CPlaceInner::Var(local, var) => {
701 assert!(matches!(layout.abi, Abi::Vector { .. }));
703 inner: CPlaceInner::VarLane(local, var, lane_idx.try_into().unwrap()),
707 CPlaceInner::VarPair(_, _, _) => unreachable!(),
708 CPlaceInner::VarLane(_, _, _) => unreachable!(),
709 CPlaceInner::Addr(ptr, None) => {
710 let field_offset = lane_layout.size * lane_idx;
711 let field_ptr = ptr.offset_i64(fx, i64::try_from(field_offset.bytes()).unwrap());
712 CPlace::for_ptr(field_ptr, lane_layout)
714 CPlaceInner::Addr(_, Some(_)) => unreachable!(),
718 pub(crate) fn place_index(
720 fx: &mut FunctionCx<'_, '_, 'tcx>,
723 let (elem_layout, ptr) = match self.layout().ty.kind() {
724 ty::Array(elem_ty, _) => (fx.layout_of(*elem_ty), self.to_ptr()),
725 ty::Slice(elem_ty) => (fx.layout_of(*elem_ty), self.to_ptr_maybe_unsized().0),
726 _ => bug!("place_index({:?})", self.layout().ty),
729 let offset = fx.bcx.ins().imul_imm(index, elem_layout.size.bytes() as i64);
731 CPlace::for_ptr(ptr.offset_value(fx, offset), elem_layout)
734 pub(crate) fn place_deref(self, fx: &mut FunctionCx<'_, '_, 'tcx>) -> CPlace<'tcx> {
735 let inner_layout = fx.layout_of(self.layout().ty.builtin_deref(true).unwrap().ty);
736 if has_ptr_meta(fx.tcx, inner_layout.ty) {
737 let (addr, extra) = self.to_cvalue(fx).load_scalar_pair(fx);
738 CPlace::for_ptr_with_extra(Pointer::new(addr), extra, inner_layout)
740 CPlace::for_ptr(Pointer::new(self.to_cvalue(fx).load_scalar(fx)), inner_layout)
744 pub(crate) fn place_ref(
746 fx: &mut FunctionCx<'_, '_, 'tcx>,
747 layout: TyAndLayout<'tcx>,
749 if has_ptr_meta(fx.tcx, self.layout().ty) {
750 let (ptr, extra) = self.to_ptr_maybe_unsized();
753 extra.expect("unsized type without metadata"),
757 CValue::by_val(self.to_ptr().get_addr(fx), layout)
761 pub(crate) fn downcast_variant(
763 fx: &FunctionCx<'_, '_, 'tcx>,
766 assert!(!self.layout().is_unsized());
767 let layout = self.layout().for_variant(fx, variant);
768 CPlace { inner: self.inner, layout }
773 pub(crate) fn assert_assignable<'tcx>(
774 fx: &FunctionCx<'_, '_, 'tcx>,
778 match (from_ty.kind(), to_ty.kind()) {
779 (ty::Ref(_, a, _), ty::Ref(_, b, _))
781 ty::RawPtr(TypeAndMut { ty: a, mutbl: _ }),
782 ty::RawPtr(TypeAndMut { ty: b, mutbl: _ }),
784 assert_assignable(fx, *a, *b);
786 (ty::Ref(_, a, _), ty::RawPtr(TypeAndMut { ty: b, mutbl: _ }))
787 | (ty::RawPtr(TypeAndMut { ty: a, mutbl: _ }), ty::Ref(_, b, _)) => {
788 assert_assignable(fx, *a, *b);
790 (ty::FnPtr(_), ty::FnPtr(_)) => {
791 let from_sig = fx.tcx.normalize_erasing_late_bound_regions(
792 ParamEnv::reveal_all(),
793 from_ty.fn_sig(fx.tcx),
797 .normalize_erasing_late_bound_regions(ParamEnv::reveal_all(), to_ty.fn_sig(fx.tcx));
800 "Can't write fn ptr with incompatible sig {:?} to place with sig {:?}\n\n{:#?}",
801 from_sig, to_sig, fx,
803 // fn(&T) -> for<'l> fn(&'l T) is allowed
805 (&ty::Dynamic(from_traits, _), &ty::Dynamic(to_traits, _)) => {
806 for (from, to) in from_traits.iter().zip(to_traits) {
808 fx.tcx.normalize_erasing_late_bound_regions(ParamEnv::reveal_all(), from);
809 let to = fx.tcx.normalize_erasing_late_bound_regions(ParamEnv::reveal_all(), to);
812 "Can't write trait object of incompatible traits {:?} to place with traits {:?}\n\n{:#?}",
813 from_traits, to_traits, fx,
816 // dyn for<'r> Trait<'r> -> dyn Trait<'_> is allowed
818 (&ty::Adt(adt_def_a, substs_a), &ty::Adt(adt_def_b, substs_b))
819 if adt_def_a.did() == adt_def_b.did() =>
821 let mut types_a = substs_a.types();
822 let mut types_b = substs_b.types();
824 match (types_a.next(), types_b.next()) {
825 (Some(a), Some(b)) => assert_assignable(fx, a, b),
826 (None, None) => return,
827 (Some(_), None) | (None, Some(_)) => panic!("{:#?}/{:#?}", from_ty, to_ty),
831 (ty::Array(a, _), ty::Array(b, _)) => assert_assignable(fx, *a, *b),
835 "Can't write value with incompatible type {:?} to place with type {:?}\n\n{:#?}",