1 //! Codegen of a single function
3 use rustc_ast::InlineAsmOptions;
4 use rustc_index::vec::IndexVec;
5 use rustc_middle::ty::adjustment::PointerCast;
6 use rustc_middle::ty::layout::FnAbiOf;
7 use rustc_middle::ty::print::with_no_trimmed_paths;
9 use crate::constant::ConstantCx;
10 use crate::debuginfo::FunctionDebugContext;
11 use crate::prelude::*;
12 use crate::pretty_clif::CommentWriter;
14 pub(crate) struct CodegenedFunction {
18 clif_comments: CommentWriter,
19 func_debug_cx: Option<FunctionDebugContext>,
22 #[cfg_attr(not(feature = "jit"), allow(dead_code))]
23 pub(crate) fn codegen_and_compile_fn<'tcx>(
25 cx: &mut crate::CodegenCx,
26 cached_context: &mut Context,
27 module: &mut dyn Module,
28 instance: Instance<'tcx>,
31 crate::PrintOnPanic(|| format!("{:?} {}", instance, tcx.symbol_name(instance).name));
33 let cached_func = std::mem::replace(&mut cached_context.func, Function::new());
34 let codegened_func = codegen_fn(tcx, cx, cached_func, module, instance);
36 compile_fn(cx, cached_context, module, codegened_func);
39 pub(crate) fn codegen_fn<'tcx>(
41 cx: &mut crate::CodegenCx,
42 cached_func: Function,
43 module: &mut dyn Module,
44 instance: Instance<'tcx>,
45 ) -> CodegenedFunction {
46 debug_assert!(!instance.substs.needs_infer());
48 let mir = tcx.instance_mir(instance.def);
49 let _mir_guard = crate::PrintOnPanic(|| {
50 let mut buf = Vec::new();
51 with_no_trimmed_paths!({
52 rustc_middle::mir::pretty::write_mir_fn(tcx, mir, &mut |_, _| Ok(()), &mut buf)
55 String::from_utf8_lossy(&buf).into_owned()
59 let symbol_name = tcx.symbol_name(instance).name.to_string();
60 let sig = get_function_sig(tcx, module.isa().triple(), instance);
61 let func_id = module.declare_function(&symbol_name, Linkage::Local, &sig).unwrap();
63 // Make the FunctionBuilder
64 let mut func_ctx = FunctionBuilderContext::new();
65 let mut func = cached_func;
67 func.name = ExternalName::user(0, func_id.as_u32());
69 func.collect_debug_info();
71 let mut bcx = FunctionBuilder::new(&mut func, &mut func_ctx);
74 let start_block = bcx.create_block();
75 let block_map: IndexVec<BasicBlock, Block> =
76 (0..mir.basic_blocks.len()).map(|_| bcx.create_block()).collect();
79 let target_config = module.target_config();
80 let pointer_type = target_config.pointer_type();
81 let clif_comments = crate::pretty_clif::CommentWriter::new(tcx, instance);
83 let func_debug_cx = if let Some(debug_context) = &mut cx.debug_context {
84 Some(debug_context.define_function(tcx, &symbol_name, mir.span))
89 let mut fx = FunctionCx {
95 constants_cx: ConstantCx::new(),
101 fn_abi: Some(RevealAllLayoutCx(tcx).fn_abi_of_instance(instance, ty::List::empty())),
105 local_map: IndexVec::with_capacity(mir.local_decls.len()),
106 caller_location: None, // set by `codegen_fn_prelude`
109 last_source_file: None,
113 tcx.sess.time("codegen clif ir", || codegen_fn_body(&mut fx, start_block));
115 // Recover all necessary data from fx, before accessing func will prevent future access to it.
116 let symbol_name = fx.symbol_name;
117 let clif_comments = fx.clif_comments;
118 let func_debug_cx = fx.func_debug_cx;
120 fx.constants_cx.finalize(fx.tcx, &mut *fx.module);
122 if cx.should_write_ir {
123 crate::pretty_clif::write_clif_file(
124 tcx.output_filenames(()),
134 verify_func(tcx, &clif_comments, &func);
136 CodegenedFunction { symbol_name, func_id, func, clif_comments, func_debug_cx }
139 pub(crate) fn compile_fn(
140 cx: &mut crate::CodegenCx,
141 cached_context: &mut Context,
142 module: &mut dyn Module,
143 codegened_func: CodegenedFunction,
145 let clif_comments = codegened_func.clif_comments;
147 // Store function in context
148 let context = cached_context;
150 context.func = codegened_func.func;
152 // If the return block is not reachable, then the SSA builder may have inserted an `iconst.i128`
153 // instruction, which doesn't have an encoding.
154 context.compute_cfg();
155 context.compute_domtree();
156 context.eliminate_unreachable_code(module.isa()).unwrap();
157 context.dce(module.isa()).unwrap();
158 // Some Cranelift optimizations expect the domtree to not yet be computed and as such don't
159 // invalidate it when it would change.
160 context.domtree.clear();
162 #[cfg(any())] // This is never true
166 let func_clone = context.func.clone();
167 let clif_comments_clone = clif_comments.clone();
168 let mut clif = String::new();
169 for flag in module.isa().flags().iter() {
170 writeln!(clif, "set {}", flag).unwrap();
172 write!(clif, "target {}", module.isa().triple().architecture.to_string()).unwrap();
173 for isa_flag in module.isa().isa_flags().iter() {
174 write!(clif, " {}", isa_flag).unwrap();
176 writeln!(clif, "\n").unwrap();
177 crate::PrintOnPanic(move || {
178 let mut clif = clif.clone();
179 ::cranelift_codegen::write::decorate_function(
180 &mut &clif_comments_clone,
190 cx.profiler.verbose_generic_activity("define function").run(|| {
191 context.want_disasm = cx.should_write_ir;
192 module.define_function(codegened_func.func_id, context).unwrap();
195 if cx.should_write_ir {
196 // Write optimized function to file for debugging
197 crate::pretty_clif::write_clif_file(
198 &cx.output_filenames,
199 &codegened_func.symbol_name,
206 if let Some(disasm) = &context.compiled_code().unwrap().disasm {
207 crate::pretty_clif::write_ir_file(
208 &cx.output_filenames,
209 &format!("{}.vcode", codegened_func.symbol_name),
210 |file| file.write_all(disasm.as_bytes()),
215 // Define debuginfo for function
216 let isa = module.isa();
217 let debug_context = &mut cx.debug_context;
218 let unwind_context = &mut cx.unwind_context;
219 cx.profiler.verbose_generic_activity("generate debug info").run(|| {
220 if let Some(debug_context) = debug_context {
221 codegened_func.func_debug_cx.unwrap().finalize(
223 codegened_func.func_id,
227 unwind_context.add_function(codegened_func.func_id, &context, isa);
231 pub(crate) fn verify_func(
233 writer: &crate::pretty_clif::CommentWriter,
236 tcx.sess.time("verify clif ir", || {
237 let flags = cranelift_codegen::settings::Flags::new(cranelift_codegen::settings::builder());
238 match cranelift_codegen::verify_function(&func, &flags) {
241 tcx.sess.err(&format!("{:?}", err));
242 let pretty_error = cranelift_codegen::print_errors::pretty_verifier_error(
244 Some(Box::new(writer)),
247 tcx.sess.fatal(&format!("cranelift verify error:\n{}", pretty_error));
253 fn codegen_fn_body(fx: &mut FunctionCx<'_, '_, '_>, start_block: Block) {
254 if !crate::constant::check_constants(fx) {
255 fx.bcx.append_block_params_for_function_params(fx.block_map[START_BLOCK]);
256 fx.bcx.switch_to_block(fx.block_map[START_BLOCK]);
257 // compilation should have been aborted
258 fx.bcx.ins().trap(TrapCode::UnreachableCodeReached);
262 let arg_uninhabited = fx
265 .any(|arg| fx.layout_of(fx.monomorphize(fx.mir.local_decls[arg].ty)).abi.is_uninhabited());
267 fx.bcx.append_block_params_for_function_params(fx.block_map[START_BLOCK]);
268 fx.bcx.switch_to_block(fx.block_map[START_BLOCK]);
269 fx.bcx.ins().trap(TrapCode::UnreachableCodeReached);
272 fx.tcx.sess.time("codegen prelude", || crate::abi::codegen_fn_prelude(fx, start_block));
274 for (bb, bb_data) in fx.mir.basic_blocks.iter_enumerated() {
275 let block = fx.get_block(bb);
276 fx.bcx.switch_to_block(block);
278 if bb_data.is_cleanup {
279 // Unwinding after panicking is not supported
282 // FIXME Once unwinding is supported and Cranelift supports marking blocks as cold, do
283 // so for cleanup blocks.
287 for stmt in &bb_data.statements {
288 fx.set_debug_loc(stmt.source_info);
289 codegen_stmt(fx, block, stmt);
292 if fx.clif_comments.enabled() {
293 let mut terminator_head = "\n".to_string();
294 with_no_trimmed_paths!({
295 bb_data.terminator().kind.fmt_head(&mut terminator_head).unwrap();
297 let inst = fx.bcx.func.layout.last_inst(block).unwrap();
298 fx.add_comment(inst, terminator_head);
301 let source_info = bb_data.terminator().source_info;
302 fx.set_debug_loc(source_info);
304 match &bb_data.terminator().kind {
305 TerminatorKind::Goto { target } => {
306 if let TerminatorKind::Return = fx.mir[*target].terminator().kind {
307 let mut can_immediately_return = true;
308 for stmt in &fx.mir[*target].statements {
309 if let StatementKind::StorageDead(_) = stmt.kind {
311 // FIXME Can sometimes happen, see rust-lang/rust#70531
312 can_immediately_return = false;
317 if can_immediately_return {
318 crate::abi::codegen_return(fx);
323 let block = fx.get_block(*target);
324 fx.bcx.ins().jump(block, &[]);
326 TerminatorKind::Return => {
327 crate::abi::codegen_return(fx);
329 TerminatorKind::Assert { cond, expected, msg, target, cleanup: _ } => {
330 if !fx.tcx.sess.overflow_checks() {
331 if let mir::AssertKind::OverflowNeg(_) = *msg {
332 let target = fx.get_block(*target);
333 fx.bcx.ins().jump(target, &[]);
337 let cond = codegen_operand(fx, cond).load_scalar(fx);
339 let target = fx.get_block(*target);
340 let failure = fx.bcx.create_block();
341 fx.bcx.set_cold_block(failure);
344 fx.bcx.ins().brz(cond, failure, &[]);
346 fx.bcx.ins().brnz(cond, failure, &[]);
348 fx.bcx.ins().jump(target, &[]);
350 fx.bcx.switch_to_block(failure);
354 AssertKind::BoundsCheck { ref len, ref index } => {
355 let len = codegen_operand(fx, len).load_scalar(fx);
356 let index = codegen_operand(fx, index).load_scalar(fx);
357 let location = fx.get_caller_location(source_info).load_scalar(fx);
361 rustc_hir::LangItem::PanicBoundsCheck,
362 &[index, len, location],
367 let msg_str = msg.description();
368 codegen_panic(fx, msg_str, source_info);
373 TerminatorKind::SwitchInt { discr, switch_ty, targets } => {
374 let discr = codegen_operand(fx, discr).load_scalar(fx);
376 let use_bool_opt = switch_ty.kind() == fx.tcx.types.bool.kind()
377 || (targets.iter().count() == 1 && targets.iter().next().unwrap().0 == 0);
379 assert_eq!(targets.iter().count(), 1);
380 let (then_value, then_block) = targets.iter().next().unwrap();
381 let then_block = fx.get_block(then_block);
382 let else_block = fx.get_block(targets.otherwise());
383 let test_zero = match then_value {
386 _ => unreachable!("{:?}", targets),
389 let discr = crate::optimize::peephole::maybe_unwrap_bint(&mut fx.bcx, discr);
390 let (discr, is_inverted) =
391 crate::optimize::peephole::maybe_unwrap_bool_not(&mut fx.bcx, discr);
392 let test_zero = if is_inverted { !test_zero } else { test_zero };
393 let discr = crate::optimize::peephole::maybe_unwrap_bint(&mut fx.bcx, discr);
394 if let Some(taken) = crate::optimize::peephole::maybe_known_branch_taken(
395 &fx.bcx, discr, test_zero,
398 fx.bcx.ins().jump(then_block, &[]);
400 fx.bcx.ins().jump(else_block, &[]);
404 fx.bcx.ins().brz(discr, then_block, &[]);
405 fx.bcx.ins().jump(else_block, &[]);
407 fx.bcx.ins().brnz(discr, then_block, &[]);
408 fx.bcx.ins().jump(else_block, &[]);
412 let mut switch = ::cranelift_frontend::Switch::new();
413 for (value, block) in targets.iter() {
414 let block = fx.get_block(block);
415 switch.set_entry(value, block);
417 let otherwise_block = fx.get_block(targets.otherwise());
418 switch.emit(&mut fx.bcx, discr, otherwise_block);
421 TerminatorKind::Call {
430 fx.tcx.sess.time("codegen call", || {
431 crate::abi::codegen_terminator_call(
433 mir::SourceInfo { span: *fn_span, ..source_info },
441 TerminatorKind::InlineAsm {
449 if options.contains(InlineAsmOptions::MAY_UNWIND) {
450 fx.tcx.sess.span_fatal(
452 "cranelift doesn't support unwinding from inline assembly.",
456 crate::inline_asm::codegen_inline_asm(
465 TerminatorKind::Resume | TerminatorKind::Abort => {
466 // FIXME implement unwinding
467 fx.bcx.ins().trap(TrapCode::UnreachableCodeReached);
469 TerminatorKind::Unreachable => {
470 fx.bcx.ins().trap(TrapCode::UnreachableCodeReached);
472 TerminatorKind::Yield { .. }
473 | TerminatorKind::FalseEdge { .. }
474 | TerminatorKind::FalseUnwind { .. }
475 | TerminatorKind::DropAndReplace { .. }
476 | TerminatorKind::GeneratorDrop => {
477 bug!("shouldn't exist at codegen {:?}", bb_data.terminator());
479 TerminatorKind::Drop { place, target, unwind: _ } => {
480 let drop_place = codegen_place(fx, *place);
481 crate::abi::codegen_drop(fx, source_info, drop_place);
483 let target_block = fx.get_block(*target);
484 fx.bcx.ins().jump(target_block, &[]);
489 fx.bcx.seal_all_blocks();
493 fn codegen_stmt<'tcx>(
494 fx: &mut FunctionCx<'_, '_, 'tcx>,
495 #[allow(unused_variables)] cur_block: Block,
496 stmt: &Statement<'tcx>,
498 let _print_guard = crate::PrintOnPanic(|| format!("stmt {:?}", stmt));
500 fx.set_debug_loc(stmt.source_info);
502 #[cfg(any())] // This is never true
504 StatementKind::StorageLive(..) | StatementKind::StorageDead(..) => {} // Those are not very useful
506 if fx.clif_comments.enabled() {
507 let inst = fx.bcx.func.layout.last_inst(cur_block).unwrap();
508 fx.add_comment(inst, format!("{:?}", stmt));
514 StatementKind::SetDiscriminant { place, variant_index } => {
515 let place = codegen_place(fx, **place);
516 crate::discriminant::codegen_set_discriminant(fx, place, *variant_index);
518 StatementKind::Assign(to_place_and_rval) => {
519 let lval = codegen_place(fx, to_place_and_rval.0);
520 let dest_layout = lval.layout();
521 match to_place_and_rval.1 {
522 Rvalue::Use(ref operand) => {
523 let val = codegen_operand(fx, operand);
524 lval.write_cvalue(fx, val);
526 Rvalue::CopyForDeref(place) => {
527 let cplace = codegen_place(fx, place);
528 let val = cplace.to_cvalue(fx);
529 lval.write_cvalue(fx, val)
531 Rvalue::Ref(_, _, place) | Rvalue::AddressOf(_, place) => {
532 let place = codegen_place(fx, place);
533 let ref_ = place.place_ref(fx, lval.layout());
534 lval.write_cvalue(fx, ref_);
536 Rvalue::ThreadLocalRef(def_id) => {
537 let val = crate::constant::codegen_tls_ref(fx, def_id, lval.layout());
538 lval.write_cvalue(fx, val);
540 Rvalue::BinaryOp(bin_op, ref lhs_rhs) => {
541 let lhs = codegen_operand(fx, &lhs_rhs.0);
542 let rhs = codegen_operand(fx, &lhs_rhs.1);
544 let res = crate::num::codegen_binop(fx, bin_op, lhs, rhs);
545 lval.write_cvalue(fx, res);
547 Rvalue::CheckedBinaryOp(bin_op, ref lhs_rhs) => {
548 let lhs = codegen_operand(fx, &lhs_rhs.0);
549 let rhs = codegen_operand(fx, &lhs_rhs.1);
551 let res = if !fx.tcx.sess.overflow_checks() {
553 crate::num::codegen_int_binop(fx, bin_op, lhs, rhs).load_scalar(fx);
554 let is_overflow = fx.bcx.ins().iconst(types::I8, 0);
555 CValue::by_val_pair(val, is_overflow, lval.layout())
557 crate::num::codegen_checked_int_binop(fx, bin_op, lhs, rhs)
560 lval.write_cvalue(fx, res);
562 Rvalue::UnaryOp(un_op, ref operand) => {
563 let operand = codegen_operand(fx, operand);
564 let layout = operand.layout();
565 let val = operand.load_scalar(fx);
566 let res = match un_op {
567 UnOp::Not => match layout.ty.kind() {
569 let res = fx.bcx.ins().icmp_imm(IntCC::Equal, val, 0);
570 CValue::by_val(fx.bcx.ins().bint(types::I8, res), layout)
572 ty::Uint(_) | ty::Int(_) => {
573 CValue::by_val(fx.bcx.ins().bnot(val), layout)
575 _ => unreachable!("un op Not for {:?}", layout.ty),
577 UnOp::Neg => match layout.ty.kind() {
578 ty::Int(IntTy::I128) => {
579 // FIXME remove this case once ineg.i128 works
581 CValue::const_val(fx, layout, ty::ScalarInt::null(layout.size));
582 crate::num::codegen_int_binop(fx, BinOp::Sub, zero, operand)
584 ty::Int(_) => CValue::by_val(fx.bcx.ins().ineg(val), layout),
585 ty::Float(_) => CValue::by_val(fx.bcx.ins().fneg(val), layout),
586 _ => unreachable!("un op Neg for {:?}", layout.ty),
589 lval.write_cvalue(fx, res);
592 CastKind::Pointer(PointerCast::ReifyFnPointer),
596 let from_ty = fx.monomorphize(operand.ty(&fx.mir.local_decls, fx.tcx));
597 let to_layout = fx.layout_of(fx.monomorphize(to_ty));
598 match *from_ty.kind() {
599 ty::FnDef(def_id, substs) => {
600 let func_ref = fx.get_function_ref(
601 Instance::resolve_for_fn_ptr(
603 ParamEnv::reveal_all(),
608 .polymorphize(fx.tcx),
610 let func_addr = fx.bcx.ins().func_addr(fx.pointer_type, func_ref);
611 lval.write_cvalue(fx, CValue::by_val(func_addr, to_layout));
613 _ => bug!("Trying to ReifyFnPointer on non FnDef {:?}", from_ty),
617 CastKind::Pointer(PointerCast::UnsafeFnPointer),
622 CastKind::Pointer(PointerCast::MutToConstPointer),
627 CastKind::Pointer(PointerCast::ArrayToPointer),
631 let to_layout = fx.layout_of(fx.monomorphize(to_ty));
632 let operand = codegen_operand(fx, operand);
633 lval.write_cvalue(fx, operand.cast_pointer_to(to_layout));
637 | CastKind::PointerExposeAddress
638 | CastKind::PointerFromExposedAddress,
642 let operand = codegen_operand(fx, operand);
643 let from_ty = operand.layout().ty;
644 let to_ty = fx.monomorphize(to_ty);
646 fn is_fat_ptr<'tcx>(fx: &FunctionCx<'_, '_, 'tcx>, ty: Ty<'tcx>) -> bool {
647 ty.builtin_deref(true)
648 .map(|ty::TypeAndMut { ty: pointee_ty, mutbl: _ }| {
649 has_ptr_meta(fx.tcx, pointee_ty)
654 if is_fat_ptr(fx, from_ty) {
655 if is_fat_ptr(fx, to_ty) {
656 // fat-ptr -> fat-ptr
657 lval.write_cvalue(fx, operand.cast_pointer_to(dest_layout));
659 // fat-ptr -> thin-ptr
660 let (ptr, _extra) = operand.load_scalar_pair(fx);
661 lval.write_cvalue(fx, CValue::by_val(ptr, dest_layout))
664 let to_clif_ty = fx.clif_type(to_ty).unwrap();
665 let from = operand.load_scalar(fx);
667 let res = clif_int_or_float_cast(
674 lval.write_cvalue(fx, CValue::by_val(res, dest_layout));
678 CastKind::Pointer(PointerCast::ClosureFnPointer(_)),
682 let operand = codegen_operand(fx, operand);
683 match *operand.layout().ty.kind() {
684 ty::Closure(def_id, substs) => {
685 let instance = Instance::resolve_closure(
689 ty::ClosureKind::FnOnce,
691 .expect("failed to normalize and resolve closure during codegen")
692 .polymorphize(fx.tcx);
693 let func_ref = fx.get_function_ref(instance);
694 let func_addr = fx.bcx.ins().func_addr(fx.pointer_type, func_ref);
695 lval.write_cvalue(fx, CValue::by_val(func_addr, lval.layout()));
697 _ => bug!("{} cannot be cast to a fn ptr", operand.layout().ty),
700 Rvalue::Cast(CastKind::Pointer(PointerCast::Unsize), ref operand, _to_ty) => {
701 let operand = codegen_operand(fx, operand);
702 operand.unsize_value(fx, lval);
704 Rvalue::Discriminant(place) => {
705 let place = codegen_place(fx, place);
706 let value = place.to_cvalue(fx);
707 crate::discriminant::codegen_get_discriminant(fx, lval, value, dest_layout);
709 Rvalue::Repeat(ref operand, times) => {
710 let operand = codegen_operand(fx, operand);
713 .eval(fx.tcx, ParamEnv::reveal_all())
715 .try_to_bits(fx.tcx.data_layout.pointer_size)
717 if operand.layout().size.bytes() == 0 {
718 // Do nothing for ZST's
719 } else if fx.clif_type(operand.layout().ty) == Some(types::I8) {
720 let times = fx.bcx.ins().iconst(fx.pointer_type, times as i64);
721 // FIXME use emit_small_memset where possible
722 let addr = lval.to_ptr().get_addr(fx);
723 let val = operand.load_scalar(fx);
724 fx.bcx.call_memset(fx.target_config, addr, val, times);
726 let loop_block = fx.bcx.create_block();
727 let loop_block2 = fx.bcx.create_block();
728 let done_block = fx.bcx.create_block();
729 let index = fx.bcx.append_block_param(loop_block, fx.pointer_type);
730 let zero = fx.bcx.ins().iconst(fx.pointer_type, 0);
731 fx.bcx.ins().jump(loop_block, &[zero]);
733 fx.bcx.switch_to_block(loop_block);
734 let done = fx.bcx.ins().icmp_imm(IntCC::Equal, index, times as i64);
735 fx.bcx.ins().brnz(done, done_block, &[]);
736 fx.bcx.ins().jump(loop_block2, &[]);
738 fx.bcx.switch_to_block(loop_block2);
739 let to = lval.place_index(fx, index);
740 to.write_cvalue(fx, operand);
741 let index = fx.bcx.ins().iadd_imm(index, 1);
742 fx.bcx.ins().jump(loop_block, &[index]);
744 fx.bcx.switch_to_block(done_block);
748 Rvalue::Len(place) => {
749 let place = codegen_place(fx, place);
750 let usize_layout = fx.layout_of(fx.tcx.types.usize);
751 let len = codegen_array_len(fx, place);
752 lval.write_cvalue(fx, CValue::by_val(len, usize_layout));
754 Rvalue::ShallowInitBox(ref operand, content_ty) => {
755 let content_ty = fx.monomorphize(content_ty);
756 let box_layout = fx.layout_of(fx.tcx.mk_box(content_ty));
757 let operand = codegen_operand(fx, operand);
758 let operand = operand.load_scalar(fx);
759 lval.write_cvalue(fx, CValue::by_val(operand, box_layout));
761 Rvalue::NullaryOp(null_op, ty) => {
765 .is_sized(fx.tcx.at(stmt.source_info.span), ParamEnv::reveal_all())
767 let layout = fx.layout_of(fx.monomorphize(ty));
768 let val = match null_op {
769 NullOp::SizeOf => layout.size.bytes(),
770 NullOp::AlignOf => layout.align.abi.bytes(),
772 let val = CValue::const_val(fx, fx.layout_of(fx.tcx.types.usize), val.into());
773 lval.write_cvalue(fx, val);
775 Rvalue::Aggregate(ref kind, ref operands) => match kind.as_ref() {
776 AggregateKind::Array(_ty) => {
777 for (i, operand) in operands.iter().enumerate() {
778 let operand = codegen_operand(fx, operand);
779 let index = fx.bcx.ins().iconst(fx.pointer_type, i as i64);
780 let to = lval.place_index(fx, index);
781 to.write_cvalue(fx, operand);
784 _ => unreachable!("shouldn't exist at codegen {:?}", to_place_and_rval.1),
788 StatementKind::StorageLive(_)
789 | StatementKind::StorageDead(_)
790 | StatementKind::Deinit(_)
792 | StatementKind::FakeRead(..)
793 | StatementKind::Retag { .. }
794 | StatementKind::AscribeUserType(..) => {}
796 StatementKind::Coverage { .. } => fx.tcx.sess.fatal("-Zcoverage is unimplemented"),
797 StatementKind::Intrinsic(ref intrinsic) => match &**intrinsic {
798 // We ignore `assume` intrinsics, they are only useful for optimizations
799 NonDivergingIntrinsic::Assume(_) => {}
800 NonDivergingIntrinsic::CopyNonOverlapping(mir::CopyNonOverlapping {
805 let dst = codegen_operand(fx, dst);
808 .pointee_info_at(fx, rustc_target::abi::Size::ZERO)
809 .expect("Expected pointer");
810 let dst = dst.load_scalar(fx);
811 let src = codegen_operand(fx, src).load_scalar(fx);
812 let count = codegen_operand(fx, count).load_scalar(fx);
813 let elem_size: u64 = pointee.size.bytes();
814 let bytes = if elem_size != 1 {
815 fx.bcx.ins().imul_imm(count, elem_size as i64)
819 fx.bcx.call_memcpy(fx.target_config, dst, src, bytes);
825 fn codegen_array_len<'tcx>(fx: &mut FunctionCx<'_, '_, 'tcx>, place: CPlace<'tcx>) -> Value {
826 match *place.layout().ty.kind() {
827 ty::Array(_elem_ty, len) => {
828 let len = fx.monomorphize(len).eval_usize(fx.tcx, ParamEnv::reveal_all()) as i64;
829 fx.bcx.ins().iconst(fx.pointer_type, len)
831 ty::Slice(_elem_ty) => {
832 place.to_ptr_maybe_unsized().1.expect("Length metadata for slice place")
834 _ => bug!("Rvalue::Len({:?})", place),
838 pub(crate) fn codegen_place<'tcx>(
839 fx: &mut FunctionCx<'_, '_, 'tcx>,
842 let mut cplace = fx.get_local_place(place.local);
844 for elem in place.projection {
846 PlaceElem::Deref => {
847 cplace = cplace.place_deref(fx);
849 PlaceElem::Field(field, _ty) => {
850 cplace = cplace.place_field(fx, field);
852 PlaceElem::Index(local) => {
853 let index = fx.get_local_place(local).to_cvalue(fx).load_scalar(fx);
854 cplace = cplace.place_index(fx, index);
856 PlaceElem::ConstantIndex { offset, min_length: _, from_end } => {
857 let offset: u64 = offset;
858 let index = if !from_end {
859 fx.bcx.ins().iconst(fx.pointer_type, offset as i64)
861 let len = codegen_array_len(fx, cplace);
862 fx.bcx.ins().iadd_imm(len, -(offset as i64))
864 cplace = cplace.place_index(fx, index);
866 PlaceElem::Subslice { from, to, from_end } => {
867 // These indices are generated by slice patterns.
868 // slice[from:-to] in Python terms.
870 let from: u64 = from;
873 match cplace.layout().ty.kind() {
874 ty::Array(elem_ty, _len) => {
875 assert!(!from_end, "array subslices are never `from_end`");
876 let elem_layout = fx.layout_of(*elem_ty);
877 let ptr = cplace.to_ptr();
878 cplace = CPlace::for_ptr(
879 ptr.offset_i64(fx, elem_layout.size.bytes() as i64 * (from as i64)),
880 fx.layout_of(fx.tcx.mk_array(*elem_ty, to - from)),
883 ty::Slice(elem_ty) => {
884 assert!(from_end, "slice subslices should be `from_end`");
885 let elem_layout = fx.layout_of(*elem_ty);
886 let (ptr, len) = cplace.to_ptr_maybe_unsized();
887 let len = len.unwrap();
888 cplace = CPlace::for_ptr_with_extra(
889 ptr.offset_i64(fx, elem_layout.size.bytes() as i64 * (from as i64)),
890 fx.bcx.ins().iadd_imm(len, -(from as i64 + to as i64)),
897 PlaceElem::Downcast(_adt_def, variant) => {
898 cplace = cplace.downcast_variant(fx, variant);
906 pub(crate) fn codegen_operand<'tcx>(
907 fx: &mut FunctionCx<'_, '_, 'tcx>,
908 operand: &Operand<'tcx>,
911 Operand::Move(place) | Operand::Copy(place) => {
912 let cplace = codegen_place(fx, *place);
915 Operand::Constant(const_) => crate::constant::codegen_constant(fx, const_),
919 pub(crate) fn codegen_panic<'tcx>(
920 fx: &mut FunctionCx<'_, '_, 'tcx>,
922 source_info: mir::SourceInfo,
924 let location = fx.get_caller_location(source_info).load_scalar(fx);
926 let msg_ptr = fx.anonymous_str(msg_str);
927 let msg_len = fx.bcx.ins().iconst(fx.pointer_type, i64::try_from(msg_str.len()).unwrap());
928 let args = [msg_ptr, msg_len, location];
930 codegen_panic_inner(fx, rustc_hir::LangItem::Panic, &args, source_info.span);
933 pub(crate) fn codegen_panic_inner<'tcx>(
934 fx: &mut FunctionCx<'_, '_, 'tcx>,
935 lang_item: rustc_hir::LangItem,
943 .unwrap_or_else(|e| fx.tcx.sess.span_fatal(span, e.to_string()));
945 let instance = Instance::mono(fx.tcx, def_id).polymorphize(fx.tcx);
946 let symbol_name = fx.tcx.symbol_name(instance).name;
951 AbiParam::new(fx.pointer_type),
952 AbiParam::new(fx.pointer_type),
953 AbiParam::new(fx.pointer_type),
959 fx.bcx.ins().trap(TrapCode::UnreachableCodeReached);