1 use rustc::ty::adjustment::PointerCast;
5 pub fn trans_fn<'clif, 'tcx, B: Backend + 'static>(
6 cx: &mut crate::CodegenCx<'clif, 'tcx, B>,
7 instance: Instance<'tcx>,
12 let mir = tcx.instance_mir(instance.def);
15 let (name, sig) = get_function_name_and_sig(tcx, instance, false);
16 let func_id = cx.module.declare_function(&name, linkage, &sig).unwrap();
17 let mut debug_context = cx
20 .map(|debug_context| FunctionDebugContext::new(tcx, debug_context, mir, &name, &sig));
22 // Make FunctionBuilder
23 let mut func = Function::with_name_signature(ExternalName::user(0, 0), sig);
24 let mut func_ctx = FunctionBuilderContext::new();
25 let mut bcx = FunctionBuilder::new(&mut func, &mut func_ctx);
28 let start_ebb = bcx.create_ebb();
29 let mut ebb_map: HashMap<BasicBlock, Ebb> = HashMap::new();
30 for (bb, _bb_data) in mir.basic_blocks().iter_enumerated() {
31 ebb_map.insert(bb, bcx.create_ebb());
35 let pointer_type = cx.module.target_config().pointer_type();
36 let clif_comments = crate::pretty_clif::CommentWriter::new(tcx, instance);
38 let mut fx = FunctionCx {
48 local_map: HashMap::new(),
51 constants_cx: &mut cx.constants_cx,
52 caches: &mut cx.caches,
53 source_info_set: indexmap::IndexSet::new(),
56 crate::abi::codegen_fn_prelude(&mut fx, start_ebb);
57 codegen_fn_content(&mut fx);
59 // Recover all necessary data from fx, before accessing func will prevent future access to it.
60 let instance = fx.instance;
61 let clif_comments = fx.clif_comments;
62 let source_info_set = fx.source_info_set;
64 #[cfg(debug_assertions)]
65 crate::pretty_clif::write_clif_file(cx.tcx, "unopt", instance, &func, &clif_comments, None);
68 verify_func(tcx, &clif_comments, &func);
71 let context = &mut cx.caches.context;
73 cx.module.define_function(func_id, context).unwrap();
75 let value_ranges = context
76 .build_value_labels_ranges(cx.module.isa())
77 .expect("value location ranges");
79 // Write optimized function to file for debugging
80 #[cfg(debug_assertions)]
81 crate::pretty_clif::write_clif_file(
90 // Define debuginfo for function
91 let isa = cx.module.isa();
94 .map(|x| x.define(tcx, context, isa, &source_info_set));
96 // Clear context to make it usable for the next function
100 fn verify_func(tcx: TyCtxt, writer: &crate::pretty_clif::CommentWriter, func: &Function) {
101 let flags = settings::Flags::new(settings::builder());
102 match ::cranelift::codegen::verify_function(&func, &flags) {
105 tcx.sess.err(&format!("{:?}", err));
106 let pretty_error = ::cranelift::codegen::print_errors::pretty_verifier_error(
109 Some(Box::new(writer)),
113 .fatal(&format!("cranelift verify error:\n{}", pretty_error));
118 fn codegen_fn_content(fx: &mut FunctionCx<'_, '_, impl Backend>) {
119 for (bb, bb_data) in fx.mir.basic_blocks().iter_enumerated() {
120 if bb_data.is_cleanup {
121 // Unwinding after panicking is not supported
125 let ebb = fx.get_ebb(bb);
126 fx.bcx.switch_to_block(ebb);
129 for stmt in &bb_data.statements {
130 fx.set_debug_loc(stmt.source_info);
131 trans_stmt(fx, ebb, stmt);
134 #[cfg(debug_assertions)]
136 let mut terminator_head = "\n".to_string();
140 .fmt_head(&mut terminator_head)
142 let inst = fx.bcx.func.layout.last_inst(ebb).unwrap();
143 fx.add_comment(inst, terminator_head);
146 fx.set_debug_loc(bb_data.terminator().source_info);
148 match &bb_data.terminator().kind {
149 TerminatorKind::Goto { target } => {
150 let ebb = fx.get_ebb(*target);
151 fx.bcx.ins().jump(ebb, &[]);
153 TerminatorKind::Return => {
154 crate::abi::codegen_return(fx);
156 TerminatorKind::Assert {
163 if !fx.tcx.sess.overflow_checks() {
164 if let mir::interpret::PanicInfo::OverflowNeg = *msg {
165 let target = fx.get_ebb(*target);
166 fx.bcx.ins().jump(target, &[]);
170 let cond = trans_operand(fx, cond).load_scalar(fx);
171 // TODO HACK brz/brnz for i8/i16 is not yet implemented
172 let cond = fx.bcx.ins().uextend(types::I32, cond);
173 let target = fx.get_ebb(*target);
175 fx.bcx.ins().brnz(cond, target, &[]);
177 fx.bcx.ins().brz(cond, target, &[]);
182 "[panic] Assert {:?} at {:?} failed.",
184 bb_data.terminator().source_info.span
189 TerminatorKind::SwitchInt {
195 let discr = trans_operand(fx, discr).load_scalar(fx);
196 let mut switch = ::cranelift::frontend::Switch::new();
197 for (i, value) in values.iter().enumerate() {
198 let ebb = fx.get_ebb(targets[i]);
199 switch.set_entry(*value as u64, ebb);
201 let otherwise_ebb = fx.get_ebb(targets[targets.len() - 1]);
202 switch.emit(&mut fx.bcx, discr, otherwise_ebb);
204 TerminatorKind::Call {
211 crate::abi::codegen_terminator_call(fx, func, args, destination);
213 TerminatorKind::Resume | TerminatorKind::Abort => {
214 trap_unreachable(fx, "[corruption] Unwinding bb reached.");
216 TerminatorKind::Unreachable => {
217 trap_unreachable(fx, "[corruption] Hit unreachable code.");
219 TerminatorKind::Yield { .. }
220 | TerminatorKind::FalseEdges { .. }
221 | TerminatorKind::FalseUnwind { .. }
222 | TerminatorKind::DropAndReplace { .. }
223 | TerminatorKind::GeneratorDrop => {
224 bug!("shouldn't exist at trans {:?}", bb_data.terminator());
226 TerminatorKind::Drop {
231 let drop_place = trans_place(fx, location);
232 crate::abi::codegen_drop(fx, drop_place);
234 let target_ebb = fx.get_ebb(*target);
235 fx.bcx.ins().jump(target_ebb, &[]);
240 fx.bcx.seal_all_blocks();
245 fx: &mut FunctionCx<'_, 'tcx, impl Backend>,
247 stmt: &Statement<'tcx>,
249 let _print_guard = PrintOnPanic(|| format!("stmt {:?}", stmt));
251 fx.set_debug_loc(stmt.source_info);
253 #[cfg(debug_assertions)]
255 StatementKind::StorageLive(..) | StatementKind::StorageDead(..) => {} // Those are not very useful
257 let inst = fx.bcx.func.layout.last_inst(cur_ebb).unwrap();
258 fx.add_comment(inst, format!("{:?}", stmt));
263 StatementKind::SetDiscriminant {
267 let place = trans_place(fx, place);
268 crate::discriminant::codegen_set_discriminant(fx, place, *variant_index);
270 StatementKind::Assign(to_place_and_rval) => {
271 let lval = trans_place(fx, &to_place_and_rval.0);
272 let dest_layout = lval.layout();
273 match &to_place_and_rval.1 {
274 Rvalue::Use(operand) => {
275 let val = trans_operand(fx, operand);
276 lval.write_cvalue(fx, val);
278 Rvalue::Ref(_, _, place) => {
279 let place = trans_place(fx, place);
280 place.write_place_ref(fx, lval);
282 Rvalue::BinaryOp(bin_op, lhs, rhs) => {
283 let lhs = trans_operand(fx, lhs);
284 let rhs = trans_operand(fx, rhs);
286 let res = crate::num::codegen_binop(fx, *bin_op, lhs, rhs);
287 lval.write_cvalue(fx, res);
289 Rvalue::CheckedBinaryOp(bin_op, lhs, rhs) => {
290 let lhs = trans_operand(fx, lhs);
291 let rhs = trans_operand(fx, rhs);
293 let res = if !fx.tcx.sess.overflow_checks() {
295 crate::num::trans_int_binop(fx, *bin_op, lhs, rhs).load_scalar(fx);
296 let is_overflow = fx.bcx.ins().iconst(types::I8, 0);
297 CValue::by_val_pair(val, is_overflow, lval.layout())
299 crate::num::trans_checked_int_binop(fx, *bin_op, lhs, rhs)
302 lval.write_cvalue(fx, res);
304 Rvalue::UnaryOp(un_op, operand) => {
305 let operand = trans_operand(fx, operand);
306 let layout = operand.layout();
307 let val = operand.load_scalar(fx);
308 let res = match un_op {
310 match layout.ty.kind {
312 let val = fx.bcx.ins().uextend(types::I32, val); // WORKAROUND for CraneStation/cranelift#466
313 let res = fx.bcx.ins().icmp_imm(IntCC::Equal, val, 0);
314 CValue::by_val(fx.bcx.ins().bint(types::I8, res), layout)
316 ty::Uint(_) | ty::Int(_) => {
317 CValue::by_val(fx.bcx.ins().bnot(val), layout)
319 _ => unimplemented!("un op Not for {:?}", layout.ty),
322 UnOp::Neg => match layout.ty.kind {
324 let zero = CValue::const_val(fx, layout.ty, 0);
325 crate::num::trans_int_binop(fx, BinOp::Sub, zero, operand)
328 CValue::by_val(fx.bcx.ins().fneg(val), layout)
330 _ => unimplemented!("un op Neg for {:?}", layout.ty),
333 lval.write_cvalue(fx, res);
335 Rvalue::Cast(CastKind::Pointer(PointerCast::ReifyFnPointer), operand, ty) => {
336 let layout = fx.layout_of(ty);
338 .monomorphize(&operand.ty(&fx.mir.local_decls, fx.tcx))
341 ty::FnDef(def_id, substs) => {
342 let func_ref = fx.get_function_ref(
343 Instance::resolve(fx.tcx, ParamEnv::reveal_all(), def_id, substs)
346 let func_addr = fx.bcx.ins().func_addr(fx.pointer_type, func_ref);
347 lval.write_cvalue(fx, CValue::by_val(func_addr, layout));
349 _ => bug!("Trying to ReifyFnPointer on non FnDef {:?}", ty),
352 Rvalue::Cast(CastKind::Pointer(PointerCast::UnsafeFnPointer), operand, ty)
353 | Rvalue::Cast(CastKind::Pointer(PointerCast::MutToConstPointer), operand, ty) => {
354 let operand = trans_operand(fx, operand);
355 let layout = fx.layout_of(ty);
356 lval.write_cvalue(fx, operand.unchecked_cast_to(layout));
358 Rvalue::Cast(CastKind::Misc, operand, to_ty) => {
359 let operand = trans_operand(fx, operand);
360 let from_ty = operand.layout().ty;
361 let to_ty = fx.monomorphize(to_ty);
364 fx: &FunctionCx<'_, 'tcx, impl Backend>,
367 ty.builtin_deref(true)
372 }| has_ptr_meta(fx.tcx, pointee_ty),
377 if is_fat_ptr(fx, from_ty) {
378 if is_fat_ptr(fx, to_ty) {
379 // fat-ptr -> fat-ptr
380 lval.write_cvalue(fx, operand.unchecked_cast_to(dest_layout));
382 // fat-ptr -> thin-ptr
383 let (ptr, _extra) = operand.load_scalar_pair(fx);
384 lval.write_cvalue(fx, CValue::by_val(ptr, dest_layout))
386 } else if let ty::Adt(adt_def, _substs) = from_ty.kind {
387 // enum -> discriminant value
388 assert!(adt_def.is_enum());
390 ty::Uint(_) | ty::Int(_) => {}
391 _ => unreachable!("cast adt {} -> {}", from_ty, to_ty),
394 let discr = crate::discriminant::codegen_get_discriminant(
399 lval.write_cvalue(fx, discr);
401 let to_clif_ty = fx.clif_type(to_ty).unwrap();
402 let from = operand.load_scalar(fx);
404 let res = clif_int_or_float_cast(
411 lval.write_cvalue(fx, CValue::by_val(res, dest_layout));
414 Rvalue::Cast(CastKind::Pointer(PointerCast::ClosureFnPointer(_)), operand, _ty) => {
415 let operand = trans_operand(fx, operand);
416 match operand.layout().ty.kind {
417 ty::Closure(def_id, substs) => {
418 let instance = Instance::resolve_closure(
422 ty::ClosureKind::FnOnce,
424 let func_ref = fx.get_function_ref(instance);
425 let func_addr = fx.bcx.ins().func_addr(fx.pointer_type, func_ref);
426 lval.write_cvalue(fx, CValue::by_val(func_addr, lval.layout()));
428 _ => bug!("{} cannot be cast to a fn ptr", operand.layout().ty),
431 Rvalue::Cast(CastKind::Pointer(PointerCast::Unsize), operand, _ty) => {
432 let operand = trans_operand(fx, operand);
433 operand.unsize_value(fx, lval);
435 Rvalue::Discriminant(place) => {
436 let place = trans_place(fx, place);
437 let value = place.to_cvalue(fx);
439 crate::discriminant::codegen_get_discriminant(fx, value, dest_layout);
440 lval.write_cvalue(fx, discr);
442 Rvalue::Repeat(operand, times) => {
443 let operand = trans_operand(fx, operand);
445 let index = fx.bcx.ins().iconst(fx.pointer_type, i as i64);
446 let to = lval.place_index(fx, index);
447 to.write_cvalue(fx, operand);
450 Rvalue::Len(place) => {
451 let place = trans_place(fx, place);
452 let usize_layout = fx.layout_of(fx.tcx.types.usize);
453 let len = codegen_array_len(fx, place);
454 lval.write_cvalue(fx, CValue::by_val(len, usize_layout));
456 Rvalue::NullaryOp(NullOp::Box, content_ty) => {
457 use rustc::middle::lang_items::ExchangeMallocFnLangItem;
459 let usize_type = fx.clif_type(fx.tcx.types.usize).unwrap();
460 let layout = fx.layout_of(content_ty);
461 let llsize = fx.bcx.ins().iconst(usize_type, layout.size.bytes() as i64);
465 .iconst(usize_type, layout.align.abi.bytes() as i64);
466 let box_layout = fx.layout_of(fx.tcx.mk_box(content_ty));
469 let def_id = match fx.tcx.lang_items().require(ExchangeMallocFnLangItem) {
474 .fatal(&format!("allocation of `{}` {}", box_layout.ty, s));
477 let instance = ty::Instance::mono(fx.tcx, def_id);
478 let func_ref = fx.get_function_ref(instance);
479 let call = fx.bcx.ins().call(func_ref, &[llsize, llalign]);
480 let ptr = fx.bcx.inst_results(call)[0];
481 lval.write_cvalue(fx, CValue::by_val(ptr, box_layout));
483 Rvalue::NullaryOp(NullOp::SizeOf, ty) => {
487 .is_sized(fx.tcx.at(DUMMY_SP), ParamEnv::reveal_all()));
488 let ty_size = fx.layout_of(ty).size.bytes();
489 let val = CValue::const_val(fx, fx.tcx.types.usize, ty_size.into());
490 lval.write_cvalue(fx, val);
492 Rvalue::Aggregate(kind, operands) => match **kind {
493 AggregateKind::Array(_ty) => {
494 for (i, operand) in operands.into_iter().enumerate() {
495 let operand = trans_operand(fx, operand);
496 let index = fx.bcx.ins().iconst(fx.pointer_type, i as i64);
497 let to = lval.place_index(fx, index);
498 to.write_cvalue(fx, operand);
501 _ => unreachable!("shouldn't exist at trans {:?}", to_place_and_rval.1),
505 StatementKind::StorageLive(_)
506 | StatementKind::StorageDead(_)
508 | StatementKind::FakeRead(..)
509 | StatementKind::Retag { .. }
510 | StatementKind::AscribeUserType(..) => {}
512 StatementKind::InlineAsm(asm) => {
513 use syntax::ast::Name;
519 let rustc::hir::InlineAsm {
520 asm: asm_code, // Name
521 outputs, // Vec<Name>
523 clobbers, // Vec<Name>
526 dialect: _, // syntax::ast::AsmDialect
529 match &*asm_code.as_str() {
531 assert_eq!(inputs, &[Name::intern("r")]);
532 assert!(outputs.is_empty(), "{:?}", outputs);
536 "cpuid" | "cpuid\n" => {
537 assert_eq!(inputs, &[Name::intern("{eax}"), Name::intern("{ecx}")]);
539 assert_eq!(outputs.len(), 4);
540 for (i, c) in (&["={eax}", "={ebx}", "={ecx}", "={edx}"])
544 assert_eq!(&outputs[i].constraint.as_str(), c);
545 assert!(!outputs[i].is_rw);
546 assert!(!outputs[i].is_indirect);
549 assert_eq!(clobbers, &[Name::intern("rbx")]);
552 assert!(!alignstack);
554 crate::trap::trap_unimplemented(
556 "__cpuid_count arch intrinsic is not supported",
560 assert_eq!(inputs, &[Name::intern("{ecx}")]);
562 assert_eq!(outputs.len(), 2);
563 for (i, c) in (&["={eax}", "={edx}"]).iter().enumerate() {
564 assert_eq!(&outputs[i].constraint.as_str(), c);
565 assert!(!outputs[i].is_rw);
566 assert!(!outputs[i].is_indirect);
569 assert_eq!(clobbers, &[]);
572 assert!(!alignstack);
574 crate::trap::trap_unimplemented(fx, "_xgetbv arch intrinsic is not supported");
576 _ if fx.tcx.symbol_name(fx.instance).name.as_str() == "__rust_probestack" => {
577 crate::trap::trap_unimplemented(fx, "__rust_probestack is not supported");
579 _ => unimpl!("Inline assembly is not supported"),
585 fn codegen_array_len<'tcx>(
586 fx: &mut FunctionCx<'_, 'tcx, impl Backend>,
589 match place.layout().ty.kind {
590 ty::Array(_elem_ty, len) => {
591 let len = crate::constant::force_eval_const(fx, len)
592 .eval_usize(fx.tcx, ParamEnv::reveal_all()) as i64;
593 fx.bcx.ins().iconst(fx.pointer_type, len)
595 ty::Slice(_elem_ty) => place
596 .to_addr_maybe_unsized(fx)
598 .expect("Length metadata for slice place"),
599 _ => bug!("Rvalue::Len({:?})", place),
603 pub fn trans_place<'tcx>(
604 fx: &mut FunctionCx<'_, 'tcx, impl Backend>,
607 let mut cplace = match &place.base {
608 PlaceBase::Local(local) => fx.get_local_place(*local),
609 PlaceBase::Static(static_) => match static_.kind {
610 StaticKind::Static => {
611 crate::constant::codegen_static_ref(fx, static_.def_id, static_.ty)
613 StaticKind::Promoted(promoted, substs) => {
614 let instance = Instance::new(static_.def_id, fx.monomorphize(&substs));
615 crate::constant::trans_promoted(fx, instance, promoted, static_.ty)
620 for elem in &*place.projection {
622 PlaceElem::Deref => {
623 cplace = cplace.place_deref(fx);
625 PlaceElem::Field(field, _ty) => {
626 cplace = cplace.place_field(fx, field);
628 PlaceElem::Index(local) => {
629 let index = fx.get_local_place(local).to_cvalue(fx).load_scalar(fx);
630 cplace = cplace.place_index(fx, index);
632 PlaceElem::ConstantIndex {
637 let index = if !from_end {
638 fx.bcx.ins().iconst(fx.pointer_type, offset as i64)
640 let len = codegen_array_len(fx, cplace);
641 fx.bcx.ins().iadd_imm(len, -(offset as i64))
643 cplace = cplace.place_index(fx, index);
645 PlaceElem::Subslice { from, to } => {
646 // These indices are generated by slice patterns.
647 // slice[from:-to] in Python terms.
649 match cplace.layout().ty.kind {
650 ty::Array(elem_ty, len) => {
651 let elem_layout = fx.layout_of(elem_ty);
652 let ptr = cplace.to_addr(fx);
653 let len = crate::constant::force_eval_const(fx, len)
654 .eval_usize(fx.tcx, ParamEnv::reveal_all());
655 cplace = CPlace::for_addr(
658 .iadd_imm(ptr, elem_layout.size.bytes() as i64 * from as i64),
659 fx.layout_of(fx.tcx.mk_array(elem_ty, len - from as u64 - to as u64)),
662 ty::Slice(elem_ty) => {
663 let elem_layout = fx.layout_of(elem_ty);
664 let (ptr, len) = cplace.to_addr_maybe_unsized(fx);
665 let len = len.unwrap();
666 cplace = CPlace::for_addr_with_extra(
669 .iadd_imm(ptr, elem_layout.size.bytes() as i64 * from as i64),
670 fx.bcx.ins().iadd_imm(len, -(from as i64 + to as i64)),
677 PlaceElem::Downcast(_adt_def, variant) => {
678 cplace = cplace.downcast_variant(fx, variant);
686 pub fn trans_operand<'tcx>(
687 fx: &mut FunctionCx<'_, 'tcx, impl Backend>,
688 operand: &Operand<'tcx>,
691 Operand::Move(place) | Operand::Copy(place) => {
692 let cplace = trans_place(fx, place);
695 Operand::Constant(const_) => crate::constant::trans_constant(fx, const_),