| //! Codegen of a single function |
| |
| use cranelift_codegen::ir::UserFuncName; |
| use cranelift_codegen::CodegenError; |
| use cranelift_frontend::{FunctionBuilder, FunctionBuilderContext}; |
| use cranelift_module::ModuleError; |
| use rustc_ast::InlineAsmOptions; |
| use rustc_index::IndexVec; |
| use rustc_middle::ty::adjustment::PointerCoercion; |
| use rustc_middle::ty::layout::FnAbiOf; |
| use rustc_middle::ty::print::with_no_trimmed_paths; |
| use rustc_middle::ty::TypeVisitableExt; |
| use rustc_monomorphize::is_call_from_compiler_builtins_to_upstream_monomorphization; |
| |
| use crate::constant::ConstantCx; |
| use crate::debuginfo::{FunctionDebugContext, TypeDebugContext}; |
| use crate::prelude::*; |
| use crate::pretty_clif::CommentWriter; |
| |
| pub(crate) struct CodegenedFunction { |
| symbol_name: String, |
| func_id: FuncId, |
| func: Function, |
| clif_comments: CommentWriter, |
| func_debug_cx: Option<FunctionDebugContext>, |
| } |
| |
| pub(crate) fn codegen_fn<'tcx>( |
| tcx: TyCtxt<'tcx>, |
| cx: &mut crate::CodegenCx, |
| type_dbg: &mut TypeDebugContext<'tcx>, |
| cached_func: Function, |
| module: &mut dyn Module, |
| instance: Instance<'tcx>, |
| ) -> CodegenedFunction { |
| debug_assert!(!instance.args.has_infer()); |
| |
| let symbol_name = tcx.symbol_name(instance).name.to_string(); |
| let _timer = tcx.prof.generic_activity_with_arg("codegen fn", &*symbol_name); |
| |
| let mir = tcx.instance_mir(instance.def); |
| let _mir_guard = crate::PrintOnPanic(|| { |
| let mut buf = Vec::new(); |
| with_no_trimmed_paths!({ |
| rustc_middle::mir::pretty::write_mir_fn(tcx, mir, &mut |_, _| Ok(()), &mut buf) |
| .unwrap(); |
| }); |
| String::from_utf8_lossy(&buf).into_owned() |
| }); |
| |
| // Declare function |
| let sig = get_function_sig(tcx, module.target_config().default_call_conv, instance); |
| let func_id = module.declare_function(&symbol_name, Linkage::Local, &sig).unwrap(); |
| |
| // Make the FunctionBuilder |
| let mut func_ctx = FunctionBuilderContext::new(); |
| let mut func = cached_func; |
| func.clear(); |
| func.name = UserFuncName::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 target_config = module.target_config(); |
| let pointer_type = target_config.pointer_type(); |
| let clif_comments = crate::pretty_clif::CommentWriter::new(tcx, instance); |
| |
| let fn_abi = RevealAllLayoutCx(tcx).fn_abi_of_instance(instance, ty::List::empty()); |
| |
| let func_debug_cx = if let Some(debug_context) = &mut cx.debug_context { |
| Some(debug_context.define_function(tcx, type_dbg, instance, fn_abi, &symbol_name, mir.span)) |
| } else { |
| None |
| }; |
| |
| let mut fx = FunctionCx { |
| cx, |
| module, |
| tcx, |
| target_config, |
| pointer_type, |
| constants_cx: ConstantCx::new(), |
| func_debug_cx, |
| |
| instance, |
| symbol_name, |
| mir, |
| fn_abi, |
| |
| bcx, |
| block_map, |
| local_map: IndexVec::with_capacity(mir.local_decls.len()), |
| caller_location: None, // set by `codegen_fn_prelude` |
| |
| clif_comments, |
| next_ssa_var: 0, |
| }; |
| |
| tcx.prof.generic_activity("codegen clif ir").run(|| codegen_fn_body(&mut fx, start_block)); |
| fx.bcx.seal_all_blocks(); |
| fx.bcx.finalize(); |
| |
| // Recover all necessary data from fx, before accessing func will prevent future access to it. |
| let symbol_name = fx.symbol_name; |
| let clif_comments = fx.clif_comments; |
| let func_debug_cx = fx.func_debug_cx; |
| |
| fx.constants_cx.finalize(fx.tcx, &mut *fx.module); |
| |
| if cx.should_write_ir { |
| crate::pretty_clif::write_clif_file( |
| tcx.output_filenames(()), |
| &symbol_name, |
| "unopt", |
| module.isa(), |
| &func, |
| &clif_comments, |
| ); |
| } |
| |
| // Verify function |
| verify_func(tcx, &clif_comments, &func); |
| |
| CodegenedFunction { symbol_name, func_id, func, clif_comments, func_debug_cx } |
| } |
| |
| pub(crate) fn compile_fn( |
| cx: &mut crate::CodegenCx, |
| cached_context: &mut Context, |
| module: &mut dyn Module, |
| codegened_func: CodegenedFunction, |
| ) { |
| let _timer = |
| cx.profiler.generic_activity_with_arg("compile function", &*codegened_func.symbol_name); |
| |
| let clif_comments = codegened_func.clif_comments; |
| |
| // Store function in context |
| let context = cached_context; |
| context.clear(); |
| context.func = codegened_func.func; |
| |
| #[cfg(any())] // This is never true |
| let _clif_guard = { |
| use std::fmt::Write; |
| |
| let func_clone = context.func.clone(); |
| let clif_comments_clone = clif_comments.clone(); |
| let mut clif = String::new(); |
| for flag in module.isa().flags().iter() { |
| writeln!(clif, "set {}", flag).unwrap(); |
| } |
| write!(clif, "target {}", module.isa().triple().architecture.to_string()).unwrap(); |
| for isa_flag in module.isa().isa_flags().iter() { |
| write!(clif, " {}", isa_flag).unwrap(); |
| } |
| writeln!(clif, "\n").unwrap(); |
| writeln!(clif, "; symbol {}", codegened_func.symbol_name).unwrap(); |
| crate::PrintOnPanic(move || { |
| let mut clif = clif.clone(); |
| ::cranelift_codegen::write::decorate_function( |
| &mut &clif_comments_clone, |
| &mut clif, |
| &func_clone, |
| ) |
| .unwrap(); |
| clif |
| }) |
| }; |
| |
| // Define function |
| cx.profiler.generic_activity("define function").run(|| { |
| context.want_disasm = cx.should_write_ir; |
| match module.define_function(codegened_func.func_id, context) { |
| Ok(()) => {} |
| Err(ModuleError::Compilation(CodegenError::ImplLimitExceeded)) => { |
| let early_dcx = rustc_session::EarlyDiagCtxt::new( |
| rustc_session::config::ErrorOutputType::default(), |
| ); |
| early_dcx.early_fatal(format!( |
| "backend implementation limit exceeded while compiling {name}", |
| name = codegened_func.symbol_name |
| )); |
| } |
| Err(err) => { |
| panic!("Error while defining {name}: {err:?}", name = codegened_func.symbol_name); |
| } |
| } |
| }); |
| |
| if cx.should_write_ir { |
| // Write optimized function to file for debugging |
| crate::pretty_clif::write_clif_file( |
| &cx.output_filenames, |
| &codegened_func.symbol_name, |
| "opt", |
| module.isa(), |
| &context.func, |
| &clif_comments, |
| ); |
| |
| if let Some(disasm) = &context.compiled_code().unwrap().vcode { |
| crate::pretty_clif::write_ir_file( |
| &cx.output_filenames, |
| &format!("{}.vcode", codegened_func.symbol_name), |
| |file| file.write_all(disasm.as_bytes()), |
| ) |
| } |
| } |
| |
| // Define debuginfo for function |
| let isa = module.isa(); |
| let debug_context = &mut cx.debug_context; |
| let unwind_context = &mut cx.unwind_context; |
| cx.profiler.generic_activity("generate debug info").run(|| { |
| if let Some(debug_context) = debug_context { |
| codegened_func.func_debug_cx.unwrap().finalize( |
| debug_context, |
| codegened_func.func_id, |
| context, |
| ); |
| } |
| unwind_context.add_function(codegened_func.func_id, &context, isa); |
| }); |
| } |
| |
| pub(crate) fn verify_func( |
| tcx: TyCtxt<'_>, |
| writer: &crate::pretty_clif::CommentWriter, |
| func: &Function, |
| ) { |
| tcx.prof.generic_activity("verify clif ir").run(|| { |
| let flags = cranelift_codegen::settings::Flags::new(cranelift_codegen::settings::builder()); |
| match cranelift_codegen::verify_function(&func, &flags) { |
| Ok(_) => {} |
| Err(err) => { |
| tcx.dcx().err(format!("{:?}", err)); |
| let pretty_error = cranelift_codegen::print_errors::pretty_verifier_error( |
| &func, |
| Some(Box::new(writer)), |
| err, |
| ); |
| tcx.dcx().fatal(format!("cranelift verify error:\n{}", pretty_error)); |
| } |
| } |
| }); |
| } |
| |
| fn codegen_fn_body(fx: &mut FunctionCx<'_, '_, '_>, start_block: Block) { |
| let arg_uninhabited = fx |
| .mir |
| .args_iter() |
| .any(|arg| fx.layout_of(fx.monomorphize(fx.mir.local_decls[arg].ty)).abi.is_uninhabited()); |
| 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]); |
| fx.bcx.ins().trap(TrapCode::UnreachableCodeReached); |
| return; |
| } |
| fx.tcx |
| .prof |
| .generic_activity("codegen prelude") |
| .run(|| crate::abi::codegen_fn_prelude(fx, start_block)); |
| |
| let reachable_blocks = traversal::mono_reachable_as_bitset(fx.mir, fx.tcx, fx.instance); |
| |
| for (bb, bb_data) in fx.mir.basic_blocks.iter_enumerated() { |
| let block = fx.get_block(bb); |
| fx.bcx.switch_to_block(block); |
| |
| if !reachable_blocks.contains(bb) { |
| // We want to skip this block, because it's not reachable. But we still create |
| // the block so terminators in other blocks can reference it. |
| fx.bcx.ins().trap(TrapCode::UnreachableCodeReached); |
| continue; |
| } |
| |
| if bb_data.is_cleanup { |
| // Unwinding after panicking is not supported |
| continue; |
| |
| // FIXME Once unwinding is supported and Cranelift supports marking blocks as cold, do |
| // so for cleanup blocks. |
| } |
| |
| 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(); |
| with_no_trimmed_paths!({ |
| 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); |
| } |
| |
| let source_info = bb_data.terminator().source_info; |
| fx.set_debug_loc(source_info); |
| |
| let _print_guard = |
| crate::PrintOnPanic(|| format!("terminator {:?}", bb_data.terminator().kind)); |
| |
| 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, unwind: _ } => { |
| if !fx.tcx.sess.overflow_checks() && msg.is_optional_overflow_check() { |
| 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.bcx.set_cold_block(failure); |
| |
| if *expected { |
| fx.bcx.ins().brif(cond, target, &[], failure, &[]); |
| } else { |
| fx.bcx.ins().brif(cond, failure, &[], 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(source_info).load_scalar(fx); |
| |
| codegen_panic_inner( |
| fx, |
| rustc_hir::LangItem::PanicBoundsCheck, |
| &[index, len, location], |
| Some(source_info.span), |
| ); |
| } |
| AssertKind::MisalignedPointerDereference { ref required, ref found } => { |
| let required = codegen_operand(fx, required).load_scalar(fx); |
| let found = codegen_operand(fx, found).load_scalar(fx); |
| let location = fx.get_caller_location(source_info).load_scalar(fx); |
| |
| codegen_panic_inner( |
| fx, |
| rustc_hir::LangItem::PanicMisalignedPointerDereference, |
| &[required, found, location], |
| Some(source_info.span), |
| ); |
| } |
| _ => { |
| let location = fx.get_caller_location(source_info).load_scalar(fx); |
| |
| codegen_panic_inner( |
| fx, |
| msg.panic_function(), |
| &[location], |
| Some(source_info.span), |
| ); |
| } |
| } |
| } |
| |
| TerminatorKind::SwitchInt { discr, targets } => { |
| let discr = codegen_operand(fx, discr); |
| let switch_ty = discr.layout().ty; |
| let discr = 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, is_inverted) = |
| crate::optimize::peephole::maybe_unwrap_bool_not(&mut fx.bcx, discr); |
| let test_zero = if is_inverted { !test_zero } else { test_zero }; |
| 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().brif(discr, else_block, &[], then_block, &[]); |
| } else { |
| fx.bcx.ins().brif(discr, then_block, &[], 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, |
| target, |
| fn_span, |
| unwind: _, |
| call_source: _, |
| } => { |
| fx.tcx.prof.generic_activity("codegen call").run(|| { |
| crate::abi::codegen_terminator_call( |
| fx, |
| mir::SourceInfo { span: *fn_span, ..source_info }, |
| func, |
| args, |
| *destination, |
| *target, |
| ) |
| }); |
| } |
| TerminatorKind::InlineAsm { |
| template, |
| operands, |
| options, |
| targets, |
| line_spans: _, |
| unwind: _, |
| } => { |
| if options.contains(InlineAsmOptions::MAY_UNWIND) { |
| fx.tcx.dcx().span_fatal( |
| source_info.span, |
| "cranelift doesn't support unwinding from inline assembly.", |
| ); |
| } |
| |
| let have_labels = if options.contains(InlineAsmOptions::NORETURN) { |
| !targets.is_empty() |
| } else { |
| targets.len() > 1 |
| }; |
| if have_labels { |
| fx.tcx.dcx().span_fatal( |
| source_info.span, |
| "cranelift doesn't support labels in inline assembly.", |
| ); |
| } |
| |
| crate::inline_asm::codegen_inline_asm_terminator( |
| fx, |
| source_info.span, |
| template, |
| operands, |
| *options, |
| targets.get(0).copied(), |
| ); |
| } |
| TerminatorKind::UnwindTerminate(reason) => { |
| codegen_unwind_terminate(fx, source_info, *reason); |
| } |
| TerminatorKind::UnwindResume => { |
| // FIXME implement unwinding |
| fx.bcx.ins().trap(TrapCode::UnreachableCodeReached); |
| } |
| TerminatorKind::Unreachable => { |
| fx.bcx.ins().trap(TrapCode::UnreachableCodeReached); |
| } |
| TerminatorKind::Yield { .. } |
| | TerminatorKind::FalseEdge { .. } |
| | TerminatorKind::FalseUnwind { .. } |
| | TerminatorKind::CoroutineDrop => { |
| bug!("shouldn't exist at codegen {:?}", bb_data.terminator()); |
| } |
| TerminatorKind::Drop { place, target, unwind: _, replace: _ } => { |
| let drop_place = codegen_place(fx, *place); |
| crate::abi::codegen_drop(fx, source_info, drop_place); |
| |
| let target_block = fx.get_block(*target); |
| fx.bcx.ins().jump(target_block, &[]); |
| } |
| }; |
| } |
| } |
| |
| 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); |
| |
| 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(); |
| with_no_trimmed_paths!({ |
| 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::CopyForDeref(place) => { |
| let cplace = codegen_place(fx, place); |
| let val = cplace.to_cvalue(fx); |
| 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 = 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(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(_) => 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::PointerCoercion(PointerCoercion::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, args) => { |
| let func_ref = fx.get_function_ref( |
| Instance::resolve_for_fn_ptr( |
| fx.tcx, |
| ParamEnv::reveal_all(), |
| def_id, |
| args, |
| ) |
| .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::PointerCoercion(PointerCoercion::UnsafeFnPointer), |
| ref operand, |
| to_ty, |
| ) |
| | Rvalue::Cast( |
| CastKind::PointerCoercion(PointerCoercion::MutToConstPointer), |
| ref operand, |
| to_ty, |
| ) |
| | Rvalue::Cast( |
| CastKind::PointerCoercion(PointerCoercion::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::IntToInt |
| | CastKind::FloatToFloat |
| | CastKind::FloatToInt |
| | CastKind::IntToFloat |
| | CastKind::FnPtrToPtr |
| | CastKind::PtrToPtr |
| | CastKind::PointerExposeProvenance |
| | CastKind::PointerWithExposedProvenance, |
| 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) |
| .is_some_and(|pointee_ty| has_ptr_meta(fx.tcx, pointee_ty)) |
| } |
| |
| 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 { |
| 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::PointerCoercion(PointerCoercion::ClosureFnPointer(_)), |
| ref operand, |
| _to_ty, |
| ) => { |
| let operand = codegen_operand(fx, operand); |
| match *operand.layout().ty.kind() { |
| ty::Closure(def_id, args) => { |
| let instance = Instance::resolve_closure( |
| fx.tcx, |
| def_id, |
| args, |
| 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::PointerCoercion(PointerCoercion::Unsize), |
| ref operand, |
| _to_ty, |
| ) => { |
| let operand = codegen_operand(fx, operand); |
| crate::unsize::coerce_unsized_into(fx, operand, lval); |
| } |
| Rvalue::Cast(CastKind::DynStar, ref operand, _) => { |
| let operand = codegen_operand(fx, operand); |
| crate::unsize::coerce_dyn_star(fx, operand, lval); |
| } |
| Rvalue::Cast(CastKind::Transmute, ref operand, _to_ty) => { |
| let operand = codegen_operand(fx, operand); |
| lval.write_cvalue_transmute(fx, operand); |
| } |
| Rvalue::Discriminant(place) => { |
| let place = codegen_place(fx, place); |
| let value = place.to_cvalue(fx); |
| crate::discriminant::codegen_get_discriminant(fx, lval, value, dest_layout); |
| } |
| Rvalue::Repeat(ref operand, times) => { |
| let operand = codegen_operand(fx, operand); |
| let times = |
| fx.monomorphize(times).eval_target_usize(fx.tcx, ParamEnv::reveal_all()); |
| 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.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().brif(done, done_block, &[], 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::ShallowInitBox(ref operand, content_ty) => { |
| let content_ty = fx.monomorphize(content_ty); |
| let box_layout = fx.layout_of(Ty::new_box(fx.tcx, content_ty)); |
| let operand = codegen_operand(fx, operand); |
| let operand = operand.load_scalar(fx); |
| lval.write_cvalue(fx, CValue::by_val(operand, box_layout)); |
| } |
| Rvalue::NullaryOp(ref null_op, ty) => { |
| assert!(lval.layout().ty.is_sized(fx.tcx, ParamEnv::reveal_all())); |
| let layout = fx.layout_of(fx.monomorphize(ty)); |
| let val = match null_op { |
| NullOp::SizeOf => layout.size.bytes(), |
| NullOp::AlignOf => layout.align.abi.bytes(), |
| NullOp::OffsetOf(fields) => { |
| layout.offset_of_subfield(fx, fields.iter()).bytes() |
| } |
| NullOp::UbChecks => { |
| let val = fx.tcx.sess.ub_checks(); |
| let val = CValue::by_val( |
| fx.bcx.ins().iconst(types::I8, i64::try_from(val).unwrap()), |
| fx.layout_of(fx.tcx.types.bool), |
| ); |
| lval.write_cvalue(fx, val); |
| return; |
| } |
| }; |
| let val = CValue::by_val( |
| fx.bcx.ins().iconst(fx.pointer_type, i64::try_from(val).unwrap()), |
| fx.layout_of(fx.tcx.types.usize), |
| ); |
| lval.write_cvalue(fx, val); |
| } |
| Rvalue::Aggregate(ref kind, ref operands) |
| if matches!(**kind, AggregateKind::RawPtr(..)) => |
| { |
| let ty = to_place_and_rval.1.ty(&fx.mir.local_decls, fx.tcx); |
| let layout = fx.layout_of(fx.monomorphize(ty)); |
| let [data, meta] = &*operands.raw else { |
| bug!("RawPtr fields: {operands:?}"); |
| }; |
| let data = codegen_operand(fx, data); |
| let meta = codegen_operand(fx, meta); |
| assert!(data.layout().ty.is_unsafe_ptr()); |
| assert!(layout.ty.is_unsafe_ptr()); |
| let ptr_val = if meta.layout().is_zst() { |
| data.cast_pointer_to(layout) |
| } else { |
| CValue::by_val_pair(data.load_scalar(fx), meta.load_scalar(fx), layout) |
| }; |
| lval.write_cvalue(fx, ptr_val); |
| } |
| Rvalue::Aggregate(ref kind, ref operands) => { |
| let (variant_index, variant_dest, active_field_index) = match **kind { |
| mir::AggregateKind::Adt(_, variant_index, _, _, active_field_index) => { |
| let variant_dest = lval.downcast_variant(fx, variant_index); |
| (variant_index, variant_dest, active_field_index) |
| } |
| _ => (FIRST_VARIANT, lval, None), |
| }; |
| if active_field_index.is_some() { |
| assert_eq!(operands.len(), 1); |
| } |
| for (i, operand) in operands.iter_enumerated() { |
| let operand = codegen_operand(fx, operand); |
| let field_index = active_field_index.unwrap_or(i); |
| let to = if let mir::AggregateKind::Array(_) = **kind { |
| let array_index = i64::from(field_index.as_u32()); |
| let index = fx.bcx.ins().iconst(fx.pointer_type, array_index); |
| variant_dest.place_index(fx, index) |
| } else { |
| variant_dest.place_field(fx, field_index) |
| }; |
| to.write_cvalue(fx, operand); |
| } |
| crate::discriminant::codegen_set_discriminant(fx, lval, variant_index); |
| } |
| } |
| } |
| StatementKind::StorageLive(_) |
| | StatementKind::StorageDead(_) |
| | StatementKind::Deinit(_) |
| | StatementKind::ConstEvalCounter |
| | StatementKind::Nop |
| | StatementKind::FakeRead(..) |
| | StatementKind::Retag { .. } |
| | StatementKind::PlaceMention(..) |
| | StatementKind::AscribeUserType(..) => {} |
| |
| StatementKind::Coverage { .. } => fx.tcx.dcx().fatal("-Zcoverage is unimplemented"), |
| StatementKind::Intrinsic(ref intrinsic) => match &**intrinsic { |
| // We ignore `assume` intrinsics, they are only useful for optimizations |
| NonDivergingIntrinsic::Assume(_) => {} |
| NonDivergingIntrinsic::CopyNonOverlapping(mir::CopyNonOverlapping { |
| src, |
| dst, |
| count, |
| }) => { |
| let dst = codegen_operand(fx, 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, src).load_scalar(fx); |
| let count = codegen_operand(fx, 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.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_target_usize(fx.tcx, ParamEnv::reveal_all()) as i64; |
| fx.bcx.ins().iconst(fx.pointer_type, len) |
| } |
| ty::Slice(_elem_ty) => place.to_ptr_unsized().1, |
| _ => 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::OpaqueCast(ty) => bug!("encountered OpaqueCast({ty}) in codegen"), |
| PlaceElem::Subtype(ty) => cplace = cplace.place_transmute_type(fx, fx.monomorphize(ty)), |
| 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(Ty::new_array(fx.tcx, *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_unsized(); |
| 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_operand(fx, const_), |
| } |
| } |
| |
| pub(crate) fn codegen_panic_nounwind<'tcx>( |
| fx: &mut FunctionCx<'_, '_, 'tcx>, |
| msg_str: &str, |
| span: Option<Span>, |
| ) { |
| let msg_ptr = fx.anonymous_str(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]; |
| |
| codegen_panic_inner(fx, rustc_hir::LangItem::PanicNounwind, &args, span); |
| } |
| |
| pub(crate) fn codegen_unwind_terminate<'tcx>( |
| fx: &mut FunctionCx<'_, '_, 'tcx>, |
| source_info: mir::SourceInfo, |
| reason: UnwindTerminateReason, |
| ) { |
| let args = []; |
| |
| codegen_panic_inner(fx, reason.lang_item(), &args, Some(source_info.span)); |
| } |
| |
| fn codegen_panic_inner<'tcx>( |
| fx: &mut FunctionCx<'_, '_, 'tcx>, |
| lang_item: rustc_hir::LangItem, |
| args: &[Value], |
| span: Option<Span>, |
| ) { |
| let def_id = fx.tcx.require_lang_item(lang_item, span); |
| |
| let instance = Instance::mono(fx.tcx, def_id).polymorphize(fx.tcx); |
| |
| if is_call_from_compiler_builtins_to_upstream_monomorphization(fx.tcx, instance) { |
| fx.bcx.ins().trap(TrapCode::User(0)); |
| return; |
| } |
| |
| let symbol_name = fx.tcx.symbol_name(instance).name; |
| |
| fx.lib_call( |
| symbol_name, |
| args.iter().map(|&arg| AbiParam::new(fx.bcx.func.dfg.value_type(arg))).collect(), |
| vec![], |
| args, |
| ); |
| |
| fx.bcx.ins().trap(TrapCode::UnreachableCodeReached); |
| } |
