From b9159e09a7c2bba670fee45b554c7c2e7aba9dd8 Mon Sep 17 00:00:00 2001 From: Santiago Pastorino Date: Tue, 1 Apr 2025 14:14:13 -0300 Subject: Use a local var for tcx --- compiler/rustc_codegen_ssa/src/mir/mod.rs | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) (limited to 'compiler/rustc_codegen_ssa/src') diff --git a/compiler/rustc_codegen_ssa/src/mir/mod.rs b/compiler/rustc_codegen_ssa/src/mir/mod.rs index 0758e5d0456..ea47d32ea03 100644 --- a/compiler/rustc_codegen_ssa/src/mir/mod.rs +++ b/compiler/rustc_codegen_ssa/src/mir/mod.rs @@ -170,6 +170,7 @@ pub fn codegen_mir<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>( ) { assert!(!instance.args.has_infer()); + let tcx = cx.tcx(); let llfn = cx.get_fn(instance); let mir = cx.tcx().instance_mir(instance.def); @@ -177,7 +178,7 @@ pub fn codegen_mir<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>( let fn_abi = cx.fn_abi_of_instance(instance, ty::List::empty()); debug!("fn_abi: {:?}", fn_abi); - if cx.tcx().codegen_fn_attrs(instance.def_id()).flags.contains(CodegenFnAttrFlags::NAKED) { + if tcx.codegen_fn_attrs(instance.def_id()).flags.contains(CodegenFnAttrFlags::NAKED) { crate::mir::naked_asm::codegen_naked_asm::(cx, &mir, instance); return; } @@ -194,7 +195,7 @@ pub fn codegen_mir<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>( } let cleanup_kinds = - base::wants_new_eh_instructions(cx.tcx().sess).then(|| analyze::cleanup_kinds(mir)); + base::wants_new_eh_instructions(tcx.sess).then(|| analyze::cleanup_kinds(mir)); let cached_llbbs: IndexVec> = mir.basic_blocks @@ -217,7 +218,7 @@ pub fn codegen_mir<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>( cleanup_kinds, landing_pads: IndexVec::from_elem(None, &mir.basic_blocks), funclets: IndexVec::from_fn_n(|_| None, mir.basic_blocks.len()), - cold_blocks: find_cold_blocks(cx.tcx(), mir), + cold_blocks: find_cold_blocks(tcx, mir), locals: locals::Locals::empty(), debug_context, per_local_var_debug_info: None, @@ -233,7 +234,7 @@ pub fn codegen_mir<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>( fx.compute_per_local_var_debug_info(&mut start_bx).unzip(); fx.per_local_var_debug_info = per_local_var_debug_info; - let traversal_order = traversal::mono_reachable_reverse_postorder(mir, cx.tcx(), instance); + let traversal_order = traversal::mono_reachable_reverse_postorder(mir, tcx, instance); let memory_locals = analyze::non_ssa_locals(&fx, &traversal_order); // Allocate variable and temp allocas -- cgit 1.4.1-3-g733a5 From 9f69c66a47d80cbced17d4d74d6e5c349db952d2 Mon Sep 17 00:00:00 2001 From: Santiago Pastorino Date: Fri, 28 Mar 2025 10:03:00 -0300 Subject: Optimize codegen of use values that are copy post monomorphization --- compiler/rustc_codegen_ssa/src/mir/mod.rs | 70 +++++++++++++++++++++++++++++-- 1 file changed, 66 insertions(+), 4 deletions(-) (limited to 'compiler/rustc_codegen_ssa/src') diff --git a/compiler/rustc_codegen_ssa/src/mir/mod.rs b/compiler/rustc_codegen_ssa/src/mir/mod.rs index ea47d32ea03..fbbf93e2dc4 100644 --- a/compiler/rustc_codegen_ssa/src/mir/mod.rs +++ b/compiler/rustc_codegen_ssa/src/mir/mod.rs @@ -3,7 +3,7 @@ use std::iter; use rustc_index::IndexVec; use rustc_index::bit_set::DenseBitSet; use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrFlags; -use rustc_middle::mir::{Local, UnwindTerminateReason, traversal}; +use rustc_middle::mir::{Body, Local, UnwindTerminateReason, traversal}; use rustc_middle::ty::layout::{FnAbiOf, HasTyCtxt, HasTypingEnv, TyAndLayout}; use rustc_middle::ty::{self, Instance, Ty, TyCtxt, TypeFoldable, TypeVisitableExt}; use rustc_middle::{bug, mir, span_bug}; @@ -173,7 +173,12 @@ pub fn codegen_mir<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>( let tcx = cx.tcx(); let llfn = cx.get_fn(instance); - let mir = cx.tcx().instance_mir(instance.def); + let mir = tcx.instance_mir(instance.def); + let mir = instance.instantiate_mir_and_normalize_erasing_regions( + tcx, + ty::TypingEnv::fully_monomorphized(), + ty::EarlyBinder::bind(mir.clone()), + ); let fn_abi = cx.fn_abi_of_instance(instance, ty::List::empty()); debug!("fn_abi: {:?}", fn_abi); @@ -183,7 +188,7 @@ pub fn codegen_mir<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>( return; } - let debug_context = cx.create_function_debug_context(instance, fn_abi, llfn, mir); + let debug_context = cx.create_function_debug_context(instance, fn_abi, llfn, &mir); let start_llbb = Bx::append_block(cx, llfn, "start"); let mut start_bx = Bx::build(cx, start_llbb); @@ -195,7 +200,7 @@ pub fn codegen_mir<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>( } let cleanup_kinds = - base::wants_new_eh_instructions(tcx.sess).then(|| analyze::cleanup_kinds(mir)); + base::wants_new_eh_instructions(tcx.sess).then(|| analyze::cleanup_kinds(&mir)); let cached_llbbs: IndexVec> = mir.basic_blocks @@ -205,6 +210,8 @@ pub fn codegen_mir<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>( }) .collect(); + let mir = tcx.arena.alloc(optimize_use_clone::(cx, mir)); + let mut fx = FunctionCx { instance, mir, @@ -311,6 +318,61 @@ pub fn codegen_mir<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>( } } +// FIXME: Move this function to mir::transform when post-mono MIR passes land. +fn optimize_use_clone<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>( + cx: &'a Bx::CodegenCx, + mut mir: Body<'tcx>, +) -> Body<'tcx> { + let tcx = cx.tcx(); + + if tcx.features().ergonomic_clones() { + for bb in mir.basic_blocks.as_mut() { + let mir::TerminatorKind::Call { + args, + destination, + target, + call_source: mir::CallSource::Use, + .. + } = &bb.terminator().kind + else { + continue; + }; + + // CallSource::Use calls always use 1 argument. + assert_eq!(args.len(), 1); + let arg = &args[0]; + + // These types are easily available from locals, so check that before + // doing DefId lookups to figure out what we're actually calling. + let arg_ty = arg.node.ty(&mir.local_decls, tcx); + + let ty::Ref(_region, inner_ty, mir::Mutability::Not) = *arg_ty.kind() else { continue }; + + if !tcx.type_is_copy_modulo_regions(cx.typing_env(), inner_ty) { + continue; + } + + let Some(arg_place) = arg.node.place() else { continue }; + + let destination_block = target.unwrap(); + + bb.statements.push(mir::Statement { + source_info: bb.terminator().source_info, + kind: mir::StatementKind::Assign(Box::new(( + *destination, + mir::Rvalue::Use(mir::Operand::Copy( + arg_place.project_deeper(&[mir::ProjectionElem::Deref], tcx), + )), + ))), + }); + + bb.terminator_mut().kind = mir::TerminatorKind::Goto { target: destination_block }; + } + } + + mir +} + /// Produces, for each argument, a `Value` pointing at the /// argument's value. As arguments are places, these are always /// indirect. -- cgit 1.4.1-3-g733a5 From 4a0ea02e3a8a799bdb58ac62078c56434cc51a27 Mon Sep 17 00:00:00 2001 From: Santiago Pastorino Date: Mon, 7 Apr 2025 16:47:22 -0300 Subject: Only clone mir body if tcx.features().ergonomic_clones() --- compiler/rustc_codegen_ssa/src/mir/mod.rs | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-) (limited to 'compiler/rustc_codegen_ssa/src') diff --git a/compiler/rustc_codegen_ssa/src/mir/mod.rs b/compiler/rustc_codegen_ssa/src/mir/mod.rs index fbbf93e2dc4..6a37889217a 100644 --- a/compiler/rustc_codegen_ssa/src/mir/mod.rs +++ b/compiler/rustc_codegen_ssa/src/mir/mod.rs @@ -173,12 +173,7 @@ pub fn codegen_mir<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>( let tcx = cx.tcx(); let llfn = cx.get_fn(instance); - let mir = tcx.instance_mir(instance.def); - let mir = instance.instantiate_mir_and_normalize_erasing_regions( - tcx, - ty::TypingEnv::fully_monomorphized(), - ty::EarlyBinder::bind(mir.clone()), - ); + let mut mir = tcx.instance_mir(instance.def); let fn_abi = cx.fn_abi_of_instance(instance, ty::List::empty()); debug!("fn_abi: {:?}", fn_abi); @@ -188,6 +183,15 @@ pub fn codegen_mir<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>( return; } + if tcx.features().ergonomic_clones() { + let monomorphized_mir = instance.instantiate_mir_and_normalize_erasing_regions( + tcx, + ty::TypingEnv::fully_monomorphized(), + ty::EarlyBinder::bind(mir.clone()), + ); + mir = tcx.arena.alloc(optimize_use_clone::(cx, monomorphized_mir)); + } + let debug_context = cx.create_function_debug_context(instance, fn_abi, llfn, &mir); let start_llbb = Bx::append_block(cx, llfn, "start"); @@ -210,8 +214,6 @@ pub fn codegen_mir<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>( }) .collect(); - let mir = tcx.arena.alloc(optimize_use_clone::(cx, mir)); - let mut fx = FunctionCx { instance, mir, -- cgit 1.4.1-3-g733a5