| //! Codegen of a single function |
| |
| use cranelift_codegen::binemit::{NullStackMapSink, NullTrapSink}; |
| use rustc_index::vec::IndexVec; |
| use rustc_middle::ty::adjustment::PointerCast; |
| use rustc_middle::ty::layout::FnAbiExt; |
| use rustc_target::abi::call::FnAbi; |
| |
| use crate::prelude::*; |
| |
| pub(crate) fn codegen_fn<'tcx>(cx: &mut crate::CodegenCx<'_, 'tcx>, instance: Instance<'tcx>) { |
| let tcx = cx.tcx; |
| |
| let _inst_guard = |
| crate::PrintOnPanic(|| format!("{:?} {}", instance, tcx.symbol_name(instance).name)); |
| debug_assert!(!instance.substs.needs_infer()); |
| |
| let mir = tcx.instance_mir(instance.def); |
| |
| // Declare function |
| let name = tcx.symbol_name(instance).name.to_string(); |
| let sig = get_function_sig(tcx, cx.module.isa().triple(), instance); |
| let func_id = cx.module.declare_function(&name, Linkage::Local, &sig).unwrap(); |
| |
| cx.cached_context.clear(); |
| |
| // Make the FunctionBuilder |
| let mut func_ctx = FunctionBuilderContext::new(); |
| let mut func = std::mem::replace(&mut cx.cached_context.func, Function::new()); |
| func.name = ExternalName::user(0, func_id.as_u32()); |
| func.signature = sig; |
| func.collect_debug_info(); |
| |
| let mut bcx = FunctionBuilder::new(&mut func, &mut func_ctx); |
| |
| // Predefine blocks |
| let start_block = bcx.create_block(); |
| let block_map: IndexVec<BasicBlock, Block> = |
| (0..mir.basic_blocks().len()).map(|_| bcx.create_block()).collect(); |
| |
| // Make FunctionCx |
| let pointer_type = cx.module.target_config().pointer_type(); |
| let clif_comments = crate::pretty_clif::CommentWriter::new(tcx, instance); |
| |
| let mut fx = FunctionCx { |
| cx, |
| tcx, |
| pointer_type, |
| |
| instance, |
| mir, |
| fn_abi: Some(FnAbi::of_instance(&RevealAllLayoutCx(tcx), instance, &[])), |
| |
| bcx, |
| block_map, |
| local_map: IndexVec::with_capacity(mir.local_decls.len()), |
| caller_location: None, // set by `codegen_fn_prelude` |
| cold_blocks: EntitySet::new(), |
| |
| clif_comments, |
| source_info_set: indexmap::IndexSet::new(), |
| next_ssa_var: 0, |
| |
| inline_asm_index: 0, |
| }; |
| |
| let arg_uninhabited = fx |
| .mir |
| .args_iter() |
| .any(|arg| fx.layout_of(fx.monomorphize(&fx.mir.local_decls[arg].ty)).abi.is_uninhabited()); |
| |
| if !crate::constant::check_constants(&mut fx) { |
| fx.bcx.append_block_params_for_function_params(fx.block_map[START_BLOCK]); |
| fx.bcx.switch_to_block(fx.block_map[START_BLOCK]); |
| crate::trap::trap_unreachable(&mut fx, "compilation should have been aborted"); |
| } else if arg_uninhabited { |
| fx.bcx.append_block_params_for_function_params(fx.block_map[START_BLOCK]); |
| fx.bcx.switch_to_block(fx.block_map[START_BLOCK]); |
| crate::trap::trap_unreachable(&mut fx, "function has uninhabited argument"); |
| } else { |
| tcx.sess.time("codegen clif ir", || { |
| tcx.sess |
| .time("codegen prelude", || crate::abi::codegen_fn_prelude(&mut fx, start_block)); |
| codegen_fn_content(&mut fx); |
| }); |
| } |
| |
| // Recover all necessary data from fx, before accessing func will prevent future access to it. |
| let instance = fx.instance; |
| let mut clif_comments = fx.clif_comments; |
| let source_info_set = fx.source_info_set; |
| let local_map = fx.local_map; |
| let cold_blocks = fx.cold_blocks; |
| |
| // Store function in context |
| let context = &mut cx.cached_context; |
| context.func = func; |
| |
| crate::pretty_clif::write_clif_file(tcx, "unopt", None, instance, &context, &clif_comments); |
| |
| // Verify function |
| verify_func(tcx, &clif_comments, &context.func); |
| |
| // Perform rust specific optimizations |
| tcx.sess.time("optimize clif ir", || { |
| crate::optimize::optimize_function( |
| tcx, |
| instance, |
| context, |
| &cold_blocks, |
| &mut clif_comments, |
| ); |
| }); |
| |
| // If the return block is not reachable, then the SSA builder may have inserted an `iconst.i128` |
| // instruction, which doesn't have an encoding. |
| context.compute_cfg(); |
| context.compute_domtree(); |
| context.eliminate_unreachable_code(cx.module.isa()).unwrap(); |
| context.dce(cx.module.isa()).unwrap(); |
| // Some Cranelift optimizations expect the domtree to not yet be computed and as such don't |
| // invalidate it when it would change. |
| context.domtree.clear(); |
| |
| context.want_disasm = crate::pretty_clif::should_write_ir(tcx); |
| |
| // Define function |
| let module = &mut cx.module; |
| tcx.sess.time("define function", || { |
| module |
| .define_function(func_id, context, &mut NullTrapSink {}, &mut NullStackMapSink {}) |
| .unwrap() |
| }); |
| |
| // Write optimized function to file for debugging |
| crate::pretty_clif::write_clif_file( |
| tcx, |
| "opt", |
| Some(cx.module.isa()), |
| instance, |
| &context, |
| &clif_comments, |
| ); |
| |
| if let Some(disasm) = &context.mach_compile_result.as_ref().unwrap().disasm { |
| crate::pretty_clif::write_ir_file( |
| tcx, |
| &format!("{}.vcode", tcx.symbol_name(instance).name), |
| |file| file.write_all(disasm.as_bytes()), |
| ) |
| } |
| |
| // Define debuginfo for function |
| let isa = cx.module.isa(); |
| let debug_context = &mut cx.debug_context; |
| let unwind_context = &mut cx.unwind_context; |
| tcx.sess.time("generate debug info", || { |
| if let Some(debug_context) = debug_context { |
| debug_context.define_function( |
| instance, |
| func_id, |
| &name, |
| isa, |
| context, |
| &source_info_set, |
| local_map, |
| ); |
| } |
| unwind_context.add_function(func_id, &context, isa); |
| }); |
| |
| // Clear context to make it usable for the next function |
| context.clear(); |
| } |
| |
| pub(crate) fn verify_func( |
| tcx: TyCtxt<'_>, |
| writer: &crate::pretty_clif::CommentWriter, |
| func: &Function, |
| ) { |
| tcx.sess.time("verify clif ir", || { |
| let flags = cranelift_codegen::settings::Flags::new(cranelift_codegen::settings::builder()); |
| match cranelift_codegen::verify_function(&func, &flags) { |
| Ok(_) => {} |
| Err(err) => { |
| tcx.sess.err(&format!("{:?}", err)); |
| let pretty_error = cranelift_codegen::print_errors::pretty_verifier_error( |
| &func, |
| None, |
| Some(Box::new(writer)), |
| err, |
| ); |
| tcx.sess.fatal(&format!("cranelift verify error:\n{}", pretty_error)); |
| } |
| } |
| }); |
| } |
| |
| fn codegen_fn_content(fx: &mut FunctionCx<'_, '_, '_>) { |
| for (bb, bb_data) in fx.mir.basic_blocks().iter_enumerated() { |
| let block = fx.get_block(bb); |
| fx.bcx.switch_to_block(block); |
| |
| if bb_data.is_cleanup { |
| // Unwinding after panicking is not supported |
| continue; |
| |
| // FIXME once unwinding is supported uncomment next lines |
| // // Unwinding is unlikely to happen, so mark cleanup block's as cold. |
| // fx.cold_blocks.insert(block); |
| } |
| |
| fx.bcx.ins().nop(); |
| for stmt in &bb_data.statements { |
| fx.set_debug_loc(stmt.source_info); |
| codegen_stmt(fx, block, stmt); |
| } |
| |
| if fx.clif_comments.enabled() { |
| let mut terminator_head = "\n".to_string(); |
| bb_data.terminator().kind.fmt_head(&mut terminator_head).unwrap(); |
| let inst = fx.bcx.func.layout.last_inst(block).unwrap(); |
| fx.add_comment(inst, terminator_head); |
| } |
| |
| fx.set_debug_loc(bb_data.terminator().source_info); |
| |
| match &bb_data.terminator().kind { |
| TerminatorKind::Goto { target } => { |
| if let TerminatorKind::Return = fx.mir[*target].terminator().kind { |
| let mut can_immediately_return = true; |
| for stmt in &fx.mir[*target].statements { |
| if let StatementKind::StorageDead(_) = stmt.kind { |
| } else { |
| // FIXME Can sometimes happen, see rust-lang/rust#70531 |
| can_immediately_return = false; |
| break; |
| } |
| } |
| |
| if can_immediately_return { |
| crate::abi::codegen_return(fx); |
| continue; |
| } |
| } |
| |
| let block = fx.get_block(*target); |
| fx.bcx.ins().jump(block, &[]); |
| } |
| TerminatorKind::Return => { |
| crate::abi::codegen_return(fx); |
| } |
| TerminatorKind::Assert { cond, expected, msg, target, cleanup: _ } => { |
| if !fx.tcx.sess.overflow_checks() { |
| if let mir::AssertKind::OverflowNeg(_) = *msg { |
| let target = fx.get_block(*target); |
| fx.bcx.ins().jump(target, &[]); |
| continue; |
| } |
| } |
| let cond = codegen_operand(fx, cond).load_scalar(fx); |
| |
| let target = fx.get_block(*target); |
| let failure = fx.bcx.create_block(); |
| fx.cold_blocks.insert(failure); |
| |
| if *expected { |
| fx.bcx.ins().brz(cond, failure, &[]); |
| } else { |
| fx.bcx.ins().brnz(cond, failure, &[]); |
| }; |
| fx.bcx.ins().jump(target, &[]); |
| |
| fx.bcx.switch_to_block(failure); |
| fx.bcx.ins().nop(); |
| |
| match msg { |
| AssertKind::BoundsCheck { ref len, ref index } => { |
| let len = codegen_operand(fx, len).load_scalar(fx); |
| let index = codegen_operand(fx, index).load_scalar(fx); |
| let location = fx |
| .get_caller_location(bb_data.terminator().source_info.span) |
| .load_scalar(fx); |
| |
| codegen_panic_inner( |
| fx, |
| rustc_hir::LangItem::PanicBoundsCheck, |
| &[index, len, location], |
| bb_data.terminator().source_info.span, |
| ); |
| } |
| _ => { |
| let msg_str = msg.description(); |
| codegen_panic(fx, msg_str, bb_data.terminator().source_info.span); |
| } |
| } |
| } |
| |
| TerminatorKind::SwitchInt { discr, switch_ty, targets } => { |
| let discr = codegen_operand(fx, discr).load_scalar(fx); |
| |
| let use_bool_opt = switch_ty.kind() == fx.tcx.types.bool.kind() |
| || (targets.iter().count() == 1 && targets.iter().next().unwrap().0 == 0); |
| if use_bool_opt { |
| assert_eq!(targets.iter().count(), 1); |
| let (then_value, then_block) = targets.iter().next().unwrap(); |
| let then_block = fx.get_block(then_block); |
| let else_block = fx.get_block(targets.otherwise()); |
| let test_zero = match then_value { |
| 0 => true, |
| 1 => false, |
| _ => unreachable!("{:?}", targets), |
| }; |
| |
| let discr = crate::optimize::peephole::maybe_unwrap_bint(&mut fx.bcx, discr); |
| let (discr, is_inverted) = |
| crate::optimize::peephole::maybe_unwrap_bool_not(&mut fx.bcx, discr); |
| let test_zero = if is_inverted { !test_zero } else { test_zero }; |
| let discr = crate::optimize::peephole::maybe_unwrap_bint(&mut fx.bcx, discr); |
| let discr = |
| crate::optimize::peephole::make_branchable_value(&mut fx.bcx, discr); |
| if let Some(taken) = crate::optimize::peephole::maybe_known_branch_taken( |
| &fx.bcx, discr, test_zero, |
| ) { |
| if taken { |
| fx.bcx.ins().jump(then_block, &[]); |
| } else { |
| fx.bcx.ins().jump(else_block, &[]); |
| } |
| } else { |
| if test_zero { |
| fx.bcx.ins().brz(discr, then_block, &[]); |
| fx.bcx.ins().jump(else_block, &[]); |
| } else { |
| fx.bcx.ins().brnz(discr, then_block, &[]); |
| fx.bcx.ins().jump(else_block, &[]); |
| } |
| } |
| } else { |
| let mut switch = ::cranelift_frontend::Switch::new(); |
| for (value, block) in targets.iter() { |
| let block = fx.get_block(block); |
| switch.set_entry(value, block); |
| } |
| let otherwise_block = fx.get_block(targets.otherwise()); |
| switch.emit(&mut fx.bcx, discr, otherwise_block); |
| } |
| } |
| TerminatorKind::Call { |
| func, |
| args, |
| destination, |
| fn_span, |
| cleanup: _, |
| from_hir_call: _, |
| } => { |
| fx.tcx.sess.time("codegen call", || { |
| crate::abi::codegen_terminator_call( |
| fx, |
| *fn_span, |
| block, |
| func, |
| args, |
| *destination, |
| ) |
| }); |
| } |
| TerminatorKind::InlineAsm { |
| template, |
| operands, |
| options, |
| destination, |
| line_spans: _, |
| } => { |
| crate::inline_asm::codegen_inline_asm( |
| fx, |
| bb_data.terminator().source_info.span, |
| template, |
| operands, |
| *options, |
| ); |
| |
| match *destination { |
| Some(destination) => { |
| let destination_block = fx.get_block(destination); |
| fx.bcx.ins().jump(destination_block, &[]); |
| } |
| None => { |
| crate::trap::trap_unreachable( |
| fx, |
| "[corruption] Returned from noreturn inline asm", |
| ); |
| } |
| } |
| } |
| TerminatorKind::Resume | TerminatorKind::Abort => { |
| trap_unreachable(fx, "[corruption] Unwinding bb reached."); |
| } |
| TerminatorKind::Unreachable => { |
| trap_unreachable(fx, "[corruption] Hit unreachable code."); |
| } |
| TerminatorKind::Yield { .. } |
| | TerminatorKind::FalseEdge { .. } |
| | TerminatorKind::FalseUnwind { .. } |
| | TerminatorKind::DropAndReplace { .. } |
| | TerminatorKind::GeneratorDrop => { |
| bug!("shouldn't exist at codegen {:?}", bb_data.terminator()); |
| } |
| TerminatorKind::Drop { place, target, unwind: _ } => { |
| let drop_place = codegen_place(fx, *place); |
| crate::abi::codegen_drop(fx, bb_data.terminator().source_info.span, drop_place); |
| |
| let target_block = fx.get_block(*target); |
| fx.bcx.ins().jump(target_block, &[]); |
| } |
| }; |
| } |
| |
| fx.bcx.seal_all_blocks(); |
| fx.bcx.finalize(); |
| } |
| |
| fn codegen_stmt<'tcx>( |
| fx: &mut FunctionCx<'_, '_, 'tcx>, |
| #[allow(unused_variables)] cur_block: Block, |
| stmt: &Statement<'tcx>, |
| ) { |
| let _print_guard = crate::PrintOnPanic(|| format!("stmt {:?}", stmt)); |
| |
| fx.set_debug_loc(stmt.source_info); |
| |
| #[cfg(disabled)] |
| match &stmt.kind { |
| StatementKind::StorageLive(..) | StatementKind::StorageDead(..) => {} // Those are not very useful |
| _ => { |
| if fx.clif_comments.enabled() { |
| let inst = fx.bcx.func.layout.last_inst(cur_block).unwrap(); |
| fx.add_comment(inst, format!("{:?}", stmt)); |
| } |
| } |
| } |
| |
| match &stmt.kind { |
| StatementKind::SetDiscriminant { place, variant_index } => { |
| let place = codegen_place(fx, **place); |
| crate::discriminant::codegen_set_discriminant(fx, place, *variant_index); |
| } |
| StatementKind::Assign(to_place_and_rval) => { |
| let lval = codegen_place(fx, to_place_and_rval.0); |
| let dest_layout = lval.layout(); |
| match to_place_and_rval.1 { |
| Rvalue::Use(ref operand) => { |
| let val = codegen_operand(fx, operand); |
| lval.write_cvalue(fx, val); |
| } |
| Rvalue::Ref(_, _, place) | Rvalue::AddressOf(_, place) => { |
| let place = codegen_place(fx, place); |
| let ref_ = place.place_ref(fx, lval.layout()); |
| lval.write_cvalue(fx, ref_); |
| } |
| Rvalue::ThreadLocalRef(def_id) => { |
| let val = crate::constant::codegen_tls_ref(fx, def_id, lval.layout()); |
| lval.write_cvalue(fx, val); |
| } |
| Rvalue::BinaryOp(bin_op, ref lhs_rhs) => { |
| let lhs = codegen_operand(fx, &lhs_rhs.0); |
| let rhs = codegen_operand(fx, &lhs_rhs.1); |
| |
| let res = crate::num::codegen_binop(fx, bin_op, lhs, rhs); |
| lval.write_cvalue(fx, res); |
| } |
| Rvalue::CheckedBinaryOp(bin_op, ref lhs_rhs) => { |
| let lhs = codegen_operand(fx, &lhs_rhs.0); |
| let rhs = codegen_operand(fx, &lhs_rhs.1); |
| |
| let res = if !fx.tcx.sess.overflow_checks() { |
| let val = |
| crate::num::codegen_int_binop(fx, bin_op, lhs, rhs).load_scalar(fx); |
| let is_overflow = fx.bcx.ins().iconst(types::I8, 0); |
| CValue::by_val_pair(val, is_overflow, lval.layout()) |
| } else { |
| crate::num::codegen_checked_int_binop(fx, bin_op, lhs, rhs) |
| }; |
| |
| lval.write_cvalue(fx, res); |
| } |
| Rvalue::UnaryOp(un_op, ref operand) => { |
| let operand = codegen_operand(fx, operand); |
| let layout = operand.layout(); |
| let val = operand.load_scalar(fx); |
| let res = match un_op { |
| UnOp::Not => match layout.ty.kind() { |
| ty::Bool => { |
| let res = fx.bcx.ins().icmp_imm(IntCC::Equal, val, 0); |
| CValue::by_val(fx.bcx.ins().bint(types::I8, res), layout) |
| } |
| ty::Uint(_) | ty::Int(_) => { |
| CValue::by_val(fx.bcx.ins().bnot(val), layout) |
| } |
| _ => unreachable!("un op Not for {:?}", layout.ty), |
| }, |
| UnOp::Neg => match layout.ty.kind() { |
| ty::Int(IntTy::I128) => { |
| // FIXME remove this case once ineg.i128 works |
| let zero = |
| CValue::const_val(fx, layout, ty::ScalarInt::null(layout.size)); |
| crate::num::codegen_int_binop(fx, BinOp::Sub, zero, operand) |
| } |
| ty::Int(_) => CValue::by_val(fx.bcx.ins().ineg(val), layout), |
| ty::Float(_) => CValue::by_val(fx.bcx.ins().fneg(val), layout), |
| _ => unreachable!("un op Neg for {:?}", layout.ty), |
| }, |
| }; |
| lval.write_cvalue(fx, res); |
| } |
| Rvalue::Cast( |
| CastKind::Pointer(PointerCast::ReifyFnPointer), |
| ref operand, |
| to_ty, |
| ) => { |
| let from_ty = fx.monomorphize(operand.ty(&fx.mir.local_decls, fx.tcx)); |
| let to_layout = fx.layout_of(fx.monomorphize(to_ty)); |
| match *from_ty.kind() { |
| ty::FnDef(def_id, substs) => { |
| let func_ref = fx.get_function_ref( |
| Instance::resolve_for_fn_ptr( |
| fx.tcx, |
| ParamEnv::reveal_all(), |
| def_id, |
| substs, |
| ) |
| .unwrap() |
| .polymorphize(fx.tcx), |
| ); |
| let func_addr = fx.bcx.ins().func_addr(fx.pointer_type, func_ref); |
| lval.write_cvalue(fx, CValue::by_val(func_addr, to_layout)); |
| } |
| _ => bug!("Trying to ReifyFnPointer on non FnDef {:?}", from_ty), |
| } |
| } |
| Rvalue::Cast( |
| CastKind::Pointer(PointerCast::UnsafeFnPointer), |
| ref operand, |
| to_ty, |
| ) |
| | Rvalue::Cast( |
| CastKind::Pointer(PointerCast::MutToConstPointer), |
| ref operand, |
| to_ty, |
| ) |
| | Rvalue::Cast( |
| CastKind::Pointer(PointerCast::ArrayToPointer), |
| ref operand, |
| to_ty, |
| ) => { |
| let to_layout = fx.layout_of(fx.monomorphize(to_ty)); |
| let operand = codegen_operand(fx, operand); |
| lval.write_cvalue(fx, operand.cast_pointer_to(to_layout)); |
| } |
| Rvalue::Cast(CastKind::Misc, ref operand, to_ty) => { |
| let operand = codegen_operand(fx, operand); |
| let from_ty = operand.layout().ty; |
| let to_ty = fx.monomorphize(to_ty); |
| |
| fn is_fat_ptr<'tcx>(fx: &FunctionCx<'_, '_, 'tcx>, ty: Ty<'tcx>) -> bool { |
| ty.builtin_deref(true) |
| .map(|ty::TypeAndMut { ty: pointee_ty, mutbl: _ }| { |
| has_ptr_meta(fx.tcx, pointee_ty) |
| }) |
| .unwrap_or(false) |
| } |
| |
| if is_fat_ptr(fx, from_ty) { |
| if is_fat_ptr(fx, to_ty) { |
| // fat-ptr -> fat-ptr |
| lval.write_cvalue(fx, operand.cast_pointer_to(dest_layout)); |
| } else { |
| // fat-ptr -> thin-ptr |
| let (ptr, _extra) = operand.load_scalar_pair(fx); |
| lval.write_cvalue(fx, CValue::by_val(ptr, dest_layout)) |
| } |
| } else if let ty::Adt(adt_def, _substs) = from_ty.kind() { |
| // enum -> discriminant value |
| assert!(adt_def.is_enum()); |
| match to_ty.kind() { |
| ty::Uint(_) | ty::Int(_) => {} |
| _ => unreachable!("cast adt {} -> {}", from_ty, to_ty), |
| } |
| let to_clif_ty = fx.clif_type(to_ty).unwrap(); |
| |
| let discriminant = crate::discriminant::codegen_get_discriminant( |
| fx, |
| operand, |
| fx.layout_of(operand.layout().ty.discriminant_ty(fx.tcx)), |
| ) |
| .load_scalar(fx); |
| |
| let res = crate::cast::clif_intcast( |
| fx, |
| discriminant, |
| to_clif_ty, |
| to_ty.is_signed(), |
| ); |
| lval.write_cvalue(fx, CValue::by_val(res, dest_layout)); |
| } else { |
| let to_clif_ty = fx.clif_type(to_ty).unwrap(); |
| let from = operand.load_scalar(fx); |
| |
| let res = clif_int_or_float_cast( |
| fx, |
| from, |
| type_sign(from_ty), |
| to_clif_ty, |
| type_sign(to_ty), |
| ); |
| lval.write_cvalue(fx, CValue::by_val(res, dest_layout)); |
| } |
| } |
| Rvalue::Cast( |
| CastKind::Pointer(PointerCast::ClosureFnPointer(_)), |
| ref operand, |
| _to_ty, |
| ) => { |
| let operand = codegen_operand(fx, operand); |
| match *operand.layout().ty.kind() { |
| ty::Closure(def_id, substs) => { |
| let instance = Instance::resolve_closure( |
| fx.tcx, |
| def_id, |
| substs, |
| ty::ClosureKind::FnOnce, |
| ) |
| .polymorphize(fx.tcx); |
| let func_ref = fx.get_function_ref(instance); |
| let func_addr = fx.bcx.ins().func_addr(fx.pointer_type, func_ref); |
| lval.write_cvalue(fx, CValue::by_val(func_addr, lval.layout())); |
| } |
| _ => bug!("{} cannot be cast to a fn ptr", operand.layout().ty), |
| } |
| } |
| Rvalue::Cast(CastKind::Pointer(PointerCast::Unsize), ref operand, _to_ty) => { |
| let operand = codegen_operand(fx, operand); |
| operand.unsize_value(fx, lval); |
| } |
| Rvalue::Discriminant(place) => { |
| let place = codegen_place(fx, place); |
| let value = place.to_cvalue(fx); |
| let discr = |
| crate::discriminant::codegen_get_discriminant(fx, value, dest_layout); |
| lval.write_cvalue(fx, discr); |
| } |
| Rvalue::Repeat(ref operand, times) => { |
| let operand = codegen_operand(fx, operand); |
| let times = fx |
| .monomorphize(times) |
| .eval(fx.tcx, ParamEnv::reveal_all()) |
| .val |
| .try_to_bits(fx.tcx.data_layout.pointer_size) |
| .unwrap(); |
| if operand.layout().size.bytes() == 0 { |
| // Do nothing for ZST's |
| } else if fx.clif_type(operand.layout().ty) == Some(types::I8) { |
| let times = fx.bcx.ins().iconst(fx.pointer_type, times as i64); |
| // FIXME use emit_small_memset where possible |
| let addr = lval.to_ptr().get_addr(fx); |
| let val = operand.load_scalar(fx); |
| fx.bcx.call_memset(fx.cx.module.target_config(), addr, val, times); |
| } else { |
| let loop_block = fx.bcx.create_block(); |
| let loop_block2 = fx.bcx.create_block(); |
| let done_block = fx.bcx.create_block(); |
| let index = fx.bcx.append_block_param(loop_block, fx.pointer_type); |
| let zero = fx.bcx.ins().iconst(fx.pointer_type, 0); |
| fx.bcx.ins().jump(loop_block, &[zero]); |
| |
| fx.bcx.switch_to_block(loop_block); |
| let done = fx.bcx.ins().icmp_imm(IntCC::Equal, index, times as i64); |
| fx.bcx.ins().brnz(done, done_block, &[]); |
| fx.bcx.ins().jump(loop_block2, &[]); |
| |
| fx.bcx.switch_to_block(loop_block2); |
| let to = lval.place_index(fx, index); |
| to.write_cvalue(fx, operand); |
| let index = fx.bcx.ins().iadd_imm(index, 1); |
| fx.bcx.ins().jump(loop_block, &[index]); |
| |
| fx.bcx.switch_to_block(done_block); |
| fx.bcx.ins().nop(); |
| } |
| } |
| Rvalue::Len(place) => { |
| let place = codegen_place(fx, place); |
| let usize_layout = fx.layout_of(fx.tcx.types.usize); |
| let len = codegen_array_len(fx, place); |
| lval.write_cvalue(fx, CValue::by_val(len, usize_layout)); |
| } |
| Rvalue::NullaryOp(NullOp::Box, content_ty) => { |
| let usize_type = fx.clif_type(fx.tcx.types.usize).unwrap(); |
| let content_ty = fx.monomorphize(content_ty); |
| let layout = fx.layout_of(content_ty); |
| let llsize = fx.bcx.ins().iconst(usize_type, layout.size.bytes() as i64); |
| let llalign = fx.bcx.ins().iconst(usize_type, layout.align.abi.bytes() as i64); |
| let box_layout = fx.layout_of(fx.tcx.mk_box(content_ty)); |
| |
| // Allocate space: |
| let def_id = |
| match fx.tcx.lang_items().require(rustc_hir::LangItem::ExchangeMalloc) { |
| Ok(id) => id, |
| Err(s) => { |
| fx.tcx |
| .sess |
| .fatal(&format!("allocation of `{}` {}", box_layout.ty, s)); |
| } |
| }; |
| let instance = ty::Instance::mono(fx.tcx, def_id).polymorphize(fx.tcx); |
| let func_ref = fx.get_function_ref(instance); |
| let call = fx.bcx.ins().call(func_ref, &[llsize, llalign]); |
| let ptr = fx.bcx.inst_results(call)[0]; |
| lval.write_cvalue(fx, CValue::by_val(ptr, box_layout)); |
| } |
| Rvalue::NullaryOp(NullOp::SizeOf, ty) => { |
| assert!( |
| lval.layout() |
| .ty |
| .is_sized(fx.tcx.at(stmt.source_info.span), ParamEnv::reveal_all()) |
| ); |
| let ty_size = fx.layout_of(fx.monomorphize(ty)).size.bytes(); |
| let val = |
| CValue::const_val(fx, fx.layout_of(fx.tcx.types.usize), ty_size.into()); |
| lval.write_cvalue(fx, val); |
| } |
| Rvalue::Aggregate(ref kind, ref operands) => match kind.as_ref() { |
| AggregateKind::Array(_ty) => { |
| for (i, operand) in operands.iter().enumerate() { |
| let operand = codegen_operand(fx, operand); |
| let index = fx.bcx.ins().iconst(fx.pointer_type, i as i64); |
| let to = lval.place_index(fx, index); |
| to.write_cvalue(fx, operand); |
| } |
| } |
| _ => unreachable!("shouldn't exist at codegen {:?}", to_place_and_rval.1), |
| }, |
| } |
| } |
| StatementKind::StorageLive(_) |
| | StatementKind::StorageDead(_) |
| | StatementKind::Nop |
| | StatementKind::FakeRead(..) |
| | StatementKind::Retag { .. } |
| | StatementKind::AscribeUserType(..) => {} |
| |
| StatementKind::LlvmInlineAsm(asm) => { |
| use rustc_span::symbol::Symbol; |
| let LlvmInlineAsm { asm, outputs, inputs } = &**asm; |
| let rustc_hir::LlvmInlineAsmInner { |
| asm: asm_code, // Name |
| outputs: output_names, // Vec<LlvmInlineAsmOutput> |
| inputs: input_names, // Vec<Name> |
| clobbers, // Vec<Name> |
| volatile, // bool |
| alignstack, // bool |
| dialect: _, |
| asm_str_style: _, |
| } = asm; |
| match asm_code.as_str().trim() { |
| "" => { |
| // Black box |
| } |
| "mov %rbx, %rsi\n cpuid\n xchg %rbx, %rsi" => { |
| assert_eq!(input_names, &[Symbol::intern("{eax}"), Symbol::intern("{ecx}")]); |
| assert_eq!(output_names.len(), 4); |
| for (i, c) in (&["={eax}", "={esi}", "={ecx}", "={edx}"]).iter().enumerate() { |
| assert_eq!(&output_names[i].constraint.as_str(), c); |
| assert!(!output_names[i].is_rw); |
| assert!(!output_names[i].is_indirect); |
| } |
| |
| assert_eq!(clobbers, &[]); |
| |
| assert!(!volatile); |
| assert!(!alignstack); |
| |
| assert_eq!(inputs.len(), 2); |
| let leaf = codegen_operand(fx, &inputs[0].1).load_scalar(fx); // %eax |
| let subleaf = codegen_operand(fx, &inputs[1].1).load_scalar(fx); // %ecx |
| |
| let (eax, ebx, ecx, edx) = |
| crate::intrinsics::codegen_cpuid_call(fx, leaf, subleaf); |
| |
| assert_eq!(outputs.len(), 4); |
| codegen_place(fx, outputs[0]) |
| .write_cvalue(fx, CValue::by_val(eax, fx.layout_of(fx.tcx.types.u32))); |
| codegen_place(fx, outputs[1]) |
| .write_cvalue(fx, CValue::by_val(ebx, fx.layout_of(fx.tcx.types.u32))); |
| codegen_place(fx, outputs[2]) |
| .write_cvalue(fx, CValue::by_val(ecx, fx.layout_of(fx.tcx.types.u32))); |
| codegen_place(fx, outputs[3]) |
| .write_cvalue(fx, CValue::by_val(edx, fx.layout_of(fx.tcx.types.u32))); |
| } |
| "xgetbv" => { |
| assert_eq!(input_names, &[Symbol::intern("{ecx}")]); |
| |
| assert_eq!(output_names.len(), 2); |
| for (i, c) in (&["={eax}", "={edx}"]).iter().enumerate() { |
| assert_eq!(&output_names[i].constraint.as_str(), c); |
| assert!(!output_names[i].is_rw); |
| assert!(!output_names[i].is_indirect); |
| } |
| |
| assert_eq!(clobbers, &[]); |
| |
| assert!(!volatile); |
| assert!(!alignstack); |
| |
| crate::trap::trap_unimplemented(fx, "_xgetbv arch intrinsic is not supported"); |
| } |
| // ___chkstk, ___chkstk_ms and __alloca are only used on Windows |
| _ if fx.tcx.symbol_name(fx.instance).name.starts_with("___chkstk") => { |
| crate::trap::trap_unimplemented(fx, "Stack probes are not supported"); |
| } |
| _ if fx.tcx.symbol_name(fx.instance).name == "__alloca" => { |
| crate::trap::trap_unimplemented(fx, "Alloca is not supported"); |
| } |
| // Used in sys::windows::abort_internal |
| "int $$0x29" => { |
| crate::trap::trap_unimplemented(fx, "Windows abort"); |
| } |
| _ => fx |
| .tcx |
| .sess |
| .span_fatal(stmt.source_info.span, "Inline assembly is not supported"), |
| } |
| } |
| StatementKind::Coverage { .. } => fx.tcx.sess.fatal("-Zcoverage is unimplemented"), |
| StatementKind::CopyNonOverlapping(inner) => { |
| let dst = codegen_operand(fx, &inner.dst); |
| let pointee = dst |
| .layout() |
| .pointee_info_at(fx, rustc_target::abi::Size::ZERO) |
| .expect("Expected pointer"); |
| let dst = dst.load_scalar(fx); |
| let src = codegen_operand(fx, &inner.src).load_scalar(fx); |
| let count = codegen_operand(fx, &inner.count).load_scalar(fx); |
| let elem_size: u64 = pointee.size.bytes(); |
| let bytes = |
| if elem_size != 1 { fx.bcx.ins().imul_imm(count, elem_size as i64) } else { count }; |
| fx.bcx.call_memcpy(fx.cx.module.target_config(), dst, src, bytes); |
| } |
| } |
| } |
| |
| fn codegen_array_len<'tcx>(fx: &mut FunctionCx<'_, '_, 'tcx>, place: CPlace<'tcx>) -> Value { |
| match *place.layout().ty.kind() { |
| ty::Array(_elem_ty, len) => { |
| let len = fx.monomorphize(len).eval_usize(fx.tcx, ParamEnv::reveal_all()) as i64; |
| fx.bcx.ins().iconst(fx.pointer_type, len) |
| } |
| ty::Slice(_elem_ty) => { |
| place.to_ptr_maybe_unsized().1.expect("Length metadata for slice place") |
| } |
| _ => bug!("Rvalue::Len({:?})", place), |
| } |
| } |
| |
| pub(crate) fn codegen_place<'tcx>( |
| fx: &mut FunctionCx<'_, '_, 'tcx>, |
| place: Place<'tcx>, |
| ) -> CPlace<'tcx> { |
| let mut cplace = fx.get_local_place(place.local); |
| |
| for elem in place.projection { |
| match elem { |
| PlaceElem::Deref => { |
| cplace = cplace.place_deref(fx); |
| } |
| PlaceElem::Field(field, _ty) => { |
| cplace = cplace.place_field(fx, field); |
| } |
| PlaceElem::Index(local) => { |
| let index = fx.get_local_place(local).to_cvalue(fx).load_scalar(fx); |
| cplace = cplace.place_index(fx, index); |
| } |
| PlaceElem::ConstantIndex { offset, min_length: _, from_end } => { |
| let offset: u64 = offset; |
| let index = if !from_end { |
| fx.bcx.ins().iconst(fx.pointer_type, offset as i64) |
| } else { |
| let len = codegen_array_len(fx, cplace); |
| fx.bcx.ins().iadd_imm(len, -(offset as i64)) |
| }; |
| cplace = cplace.place_index(fx, index); |
| } |
| PlaceElem::Subslice { from, to, from_end } => { |
| // These indices are generated by slice patterns. |
| // slice[from:-to] in Python terms. |
| |
| let from: u64 = from; |
| let to: u64 = to; |
| |
| match cplace.layout().ty.kind() { |
| ty::Array(elem_ty, _len) => { |
| assert!(!from_end, "array subslices are never `from_end`"); |
| let elem_layout = fx.layout_of(elem_ty); |
| let ptr = cplace.to_ptr(); |
| cplace = CPlace::for_ptr( |
| ptr.offset_i64(fx, elem_layout.size.bytes() as i64 * (from as i64)), |
| fx.layout_of(fx.tcx.mk_array(elem_ty, to - from)), |
| ); |
| } |
| ty::Slice(elem_ty) => { |
| assert!(from_end, "slice subslices should be `from_end`"); |
| let elem_layout = fx.layout_of(elem_ty); |
| let (ptr, len) = cplace.to_ptr_maybe_unsized(); |
| let len = len.unwrap(); |
| cplace = CPlace::for_ptr_with_extra( |
| ptr.offset_i64(fx, elem_layout.size.bytes() as i64 * (from as i64)), |
| fx.bcx.ins().iadd_imm(len, -(from as i64 + to as i64)), |
| cplace.layout(), |
| ); |
| } |
| _ => unreachable!(), |
| } |
| } |
| PlaceElem::Downcast(_adt_def, variant) => { |
| cplace = cplace.downcast_variant(fx, variant); |
| } |
| } |
| } |
| |
| cplace |
| } |
| |
| pub(crate) fn codegen_operand<'tcx>( |
| fx: &mut FunctionCx<'_, '_, 'tcx>, |
| operand: &Operand<'tcx>, |
| ) -> CValue<'tcx> { |
| match operand { |
| Operand::Move(place) | Operand::Copy(place) => { |
| let cplace = codegen_place(fx, *place); |
| cplace.to_cvalue(fx) |
| } |
| Operand::Constant(const_) => crate::constant::codegen_constant(fx, const_), |
| } |
| } |
| |
| pub(crate) fn codegen_panic<'tcx>(fx: &mut FunctionCx<'_, '_, 'tcx>, msg_str: &str, span: Span) { |
| let location = fx.get_caller_location(span).load_scalar(fx); |
| |
| let msg_ptr = fx.anonymous_str("assert", msg_str); |
| let msg_len = fx.bcx.ins().iconst(fx.pointer_type, i64::try_from(msg_str.len()).unwrap()); |
| let args = [msg_ptr, msg_len, location]; |
| |
| codegen_panic_inner(fx, rustc_hir::LangItem::Panic, &args, span); |
| } |
| |
| pub(crate) fn codegen_panic_inner<'tcx>( |
| fx: &mut FunctionCx<'_, '_, 'tcx>, |
| lang_item: rustc_hir::LangItem, |
| args: &[Value], |
| span: Span, |
| ) { |
| let def_id = |
| fx.tcx.lang_items().require(lang_item).unwrap_or_else(|s| fx.tcx.sess.span_fatal(span, &s)); |
| |
| let instance = Instance::mono(fx.tcx, def_id).polymorphize(fx.tcx); |
| let symbol_name = fx.tcx.symbol_name(instance).name; |
| |
| fx.lib_call( |
| &*symbol_name, |
| vec![ |
| AbiParam::new(fx.pointer_type), |
| AbiParam::new(fx.pointer_type), |
| AbiParam::new(fx.pointer_type), |
| ], |
| vec![], |
| args, |
| ); |
| |
| crate::trap::trap_unreachable(fx, "panic lang item returned"); |
| } |
