From 014b29eecfbe79e4a6ca6d845907ebebeee53f1d Mon Sep 17 00:00:00 2001 From: Camille GILLOT Date: Sun, 26 Feb 2023 13:42:28 +0000 Subject: [PATCH] Remove ConstGoto and SeparateConstSwitch. --- .../rustc_mir_transform/src/const_goto.rs | 128 ------- compiler/rustc_mir_transform/src/lib.rs | 7 - .../src/separate_const_switch.rs | 343 ------------------ .../const_goto.issue_77355_opt.ConstGoto.diff | 50 --- tests/mir-opt/const_goto.rs | 19 - ...onst_goto_const_eval_fail.f.ConstGoto.diff | 51 --- ..._goto_const_eval_fail.f.JumpThreading.diff | 47 +++ tests/mir-opt/const_goto_const_eval_fail.rs | 2 +- ...oto_storage.match_nested_if.ConstGoto.diff | 102 ------ tests/mir-opt/const_goto_storage.rs | 22 -- ...macro.issue_77355_opt.PreCodegen.after.mir | 22 ++ tests/mir-opt/pre-codegen/matches_macro.rs | 27 ++ ..._const_switch.identity.JumpThreading.diff} | 19 +- tests/mir-opt/separate_const_switch.rs | 4 +- ...nst_switch.too_complex.JumpThreading.diff} | 15 +- 15 files changed, 125 insertions(+), 733 deletions(-) delete mode 100644 compiler/rustc_mir_transform/src/const_goto.rs delete mode 100644 compiler/rustc_mir_transform/src/separate_const_switch.rs delete mode 100644 tests/mir-opt/const_goto.issue_77355_opt.ConstGoto.diff delete mode 100644 tests/mir-opt/const_goto.rs delete mode 100644 tests/mir-opt/const_goto_const_eval_fail.f.ConstGoto.diff create mode 100644 tests/mir-opt/const_goto_const_eval_fail.f.JumpThreading.diff delete mode 100644 tests/mir-opt/const_goto_storage.match_nested_if.ConstGoto.diff delete mode 100644 tests/mir-opt/const_goto_storage.rs create mode 100644 tests/mir-opt/pre-codegen/matches_macro.issue_77355_opt.PreCodegen.after.mir create mode 100644 tests/mir-opt/pre-codegen/matches_macro.rs rename tests/mir-opt/{separate_const_switch.identity.SeparateConstSwitch.diff => separate_const_switch.identity.JumpThreading.diff} (87%) rename tests/mir-opt/{separate_const_switch.too_complex.SeparateConstSwitch.diff => separate_const_switch.too_complex.JumpThreading.diff} (83%) diff --git a/compiler/rustc_mir_transform/src/const_goto.rs b/compiler/rustc_mir_transform/src/const_goto.rs deleted file mode 100644 index cb5b66b314d..00000000000 --- a/compiler/rustc_mir_transform/src/const_goto.rs +++ /dev/null @@ -1,128 +0,0 @@ -//! This pass optimizes the following sequence -//! ```rust,ignore (example) -//! bb2: { -//! _2 = const true; -//! goto -> bb3; -//! } -//! -//! bb3: { -//! switchInt(_2) -> [false: bb4, otherwise: bb5]; -//! } -//! ``` -//! into -//! ```rust,ignore (example) -//! bb2: { -//! _2 = const true; -//! goto -> bb5; -//! } -//! ``` - -use rustc_middle::mir::*; -use rustc_middle::ty::TyCtxt; -use rustc_middle::{mir::visit::Visitor, ty::ParamEnv}; - -use super::simplify::{simplify_cfg, simplify_locals}; - -pub struct ConstGoto; - -impl<'tcx> MirPass<'tcx> for ConstGoto { - fn is_enabled(&self, sess: &rustc_session::Session) -> bool { - // This pass participates in some as-of-yet untested unsoundness found - // in https://github.com/rust-lang/rust/issues/112460 - sess.mir_opt_level() >= 2 && sess.opts.unstable_opts.unsound_mir_opts - } - - fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { - trace!("Running ConstGoto on {:?}", body.source); - let param_env = tcx.param_env_reveal_all_normalized(body.source.def_id()); - let mut opt_finder = - ConstGotoOptimizationFinder { tcx, body, optimizations: vec![], param_env }; - opt_finder.visit_body(body); - let should_simplify = !opt_finder.optimizations.is_empty(); - for opt in opt_finder.optimizations { - let block = &mut body.basic_blocks_mut()[opt.bb_with_goto]; - block.statements.extend(opt.stmts_move_up); - let terminator = block.terminator_mut(); - let new_goto = TerminatorKind::Goto { target: opt.target_to_use_in_goto }; - debug!("SUCCESS: replacing `{:?}` with `{:?}`", terminator.kind, new_goto); - terminator.kind = new_goto; - } - - // if we applied optimizations, we potentially have some cfg to cleanup to - // make it easier for further passes - if should_simplify { - simplify_cfg(body); - simplify_locals(body, tcx); - } - } -} - -impl<'tcx> Visitor<'tcx> for ConstGotoOptimizationFinder<'_, 'tcx> { - fn visit_basic_block_data(&mut self, block: BasicBlock, data: &BasicBlockData<'tcx>) { - if data.is_cleanup { - // Because of the restrictions around control flow in cleanup blocks, we don't perform - // this optimization at all in such blocks. - return; - } - self.super_basic_block_data(block, data); - } - - fn visit_terminator(&mut self, terminator: &Terminator<'tcx>, location: Location) { - let _: Option<_> = try { - let target = terminator.kind.as_goto()?; - // We only apply this optimization if the last statement is a const assignment - let last_statement = self.body.basic_blocks[location.block].statements.last()?; - - if let (place, Rvalue::Use(Operand::Constant(_const))) = - last_statement.kind.as_assign()? - { - // We found a constant being assigned to `place`. - // Now check that the target of this Goto switches on this place. - let target_bb = &self.body.basic_blocks[target]; - - // The `StorageDead(..)` statement does not affect the functionality of mir. - // We can move this part of the statement up to the predecessor. - let mut stmts_move_up = Vec::new(); - for stmt in &target_bb.statements { - if let StatementKind::StorageDead(..) = stmt.kind { - stmts_move_up.push(stmt.clone()) - } else { - None?; - } - } - - let target_bb_terminator = target_bb.terminator(); - let (discr, targets) = target_bb_terminator.kind.as_switch()?; - if discr.place() == Some(*place) { - let switch_ty = place.ty(self.body.local_decls(), self.tcx).ty; - debug_assert_eq!(switch_ty, _const.ty()); - // We now know that the Switch matches on the const place, and it is statementless - // Now find which value in the Switch matches the const value. - let const_value = _const.const_.try_eval_bits(self.tcx, self.param_env)?; - let target_to_use_in_goto = targets.target_for_value(const_value); - self.optimizations.push(OptimizationToApply { - bb_with_goto: location.block, - target_to_use_in_goto, - stmts_move_up, - }); - } - } - Some(()) - }; - - self.super_terminator(terminator, location); - } -} - -struct OptimizationToApply<'tcx> { - bb_with_goto: BasicBlock, - target_to_use_in_goto: BasicBlock, - stmts_move_up: Vec>, -} - -pub struct ConstGotoOptimizationFinder<'a, 'tcx> { - tcx: TyCtxt<'tcx>, - body: &'a Body<'tcx>, - param_env: ParamEnv<'tcx>, - optimizations: Vec>, -} diff --git a/compiler/rustc_mir_transform/src/lib.rs b/compiler/rustc_mir_transform/src/lib.rs index 8e5d69605aa..281bf3d44e6 100644 --- a/compiler/rustc_mir_transform/src/lib.rs +++ b/compiler/rustc_mir_transform/src/lib.rs @@ -59,7 +59,6 @@ mod add_subtyping_projections; pub mod cleanup_post_borrowck; mod const_debuginfo; -mod const_goto; mod const_prop; mod const_prop_lint; mod copy_prop; @@ -103,7 +102,6 @@ mod remove_zsts; mod required_consts; mod reveal_all; -mod separate_const_switch; mod shim; mod ssa; // This pass is public to allow external drivers to perform MIR cleanup @@ -590,7 +588,6 @@ fn o1(x: T) -> WithMinOptLevel { // Has to run after `slice::len` lowering &normalize_array_len::NormalizeArrayLen, - &const_goto::ConstGoto, &ref_prop::ReferencePropagation, &sroa::ScalarReplacementOfAggregates, &match_branches::MatchBranchSimplification, @@ -601,10 +598,6 @@ fn o1(x: T) -> WithMinOptLevel { &dead_store_elimination::DeadStoreElimination::Initial, &gvn::GVN, &simplify::SimplifyLocals::AfterGVN, - // Perform `SeparateConstSwitch` after SSA-based analyses, as cloning blocks may - // destroy the SSA property. It should still happen before const-propagation, so the - // latter pass will leverage the created opportunities. - &separate_const_switch::SeparateConstSwitch, &dataflow_const_prop::DataflowConstProp, &const_debuginfo::ConstDebugInfo, &o1(simplify_branches::SimplifyConstCondition::AfterConstProp), diff --git a/compiler/rustc_mir_transform/src/separate_const_switch.rs b/compiler/rustc_mir_transform/src/separate_const_switch.rs deleted file mode 100644 index 7120ef72142..00000000000 --- a/compiler/rustc_mir_transform/src/separate_const_switch.rs +++ /dev/null @@ -1,343 +0,0 @@ -//! A pass that duplicates switch-terminated blocks -//! into a new copy for each predecessor, provided -//! the predecessor sets the value being switched -//! over to a constant. -//! -//! The purpose of this pass is to help constant -//! propagation passes to simplify the switch terminator -//! of the copied blocks into gotos when some predecessors -//! statically determine the output of switches. -//! -//! ```text -//! x = 12 --- ---> something -//! \ / 12 -//! --> switch x -//! / \ otherwise -//! x = y --- ---> something else -//! ``` -//! becomes -//! ```text -//! x = 12 ---> switch x ------> something -//! \ / 12 -//! X -//! / \ otherwise -//! x = y ---> switch x ------> something else -//! ``` -//! so it can hopefully later be turned by another pass into -//! ```text -//! x = 12 --------------------> something -//! / 12 -//! / -//! / otherwise -//! x = y ---- switch x ------> something else -//! ``` -//! -//! This optimization is meant to cover simple cases -//! like `?` desugaring. For now, it thus focuses on -//! simplicity rather than completeness (it notably -//! sometimes duplicates abusively). - -use rustc_middle::mir::*; -use rustc_middle::ty::TyCtxt; -use smallvec::SmallVec; - -pub struct SeparateConstSwitch; - -impl<'tcx> MirPass<'tcx> for SeparateConstSwitch { - fn is_enabled(&self, sess: &rustc_session::Session) -> bool { - // This pass participates in some as-of-yet untested unsoundness found - // in https://github.com/rust-lang/rust/issues/112460 - sess.mir_opt_level() >= 2 && sess.opts.unstable_opts.unsound_mir_opts - } - - fn run_pass(&self, _: TyCtxt<'tcx>, body: &mut Body<'tcx>) { - // If execution did something, applying a simplification layer - // helps later passes optimize the copy away. - if separate_const_switch(body) > 0 { - super::simplify::simplify_cfg(body); - } - } -} - -/// Returns the amount of blocks that were duplicated -pub fn separate_const_switch(body: &mut Body<'_>) -> usize { - let mut new_blocks: SmallVec<[(BasicBlock, BasicBlock); 6]> = SmallVec::new(); - let predecessors = body.basic_blocks.predecessors(); - 'block_iter: for (block_id, block) in body.basic_blocks.iter_enumerated() { - if let TerminatorKind::SwitchInt { - discr: Operand::Copy(switch_place) | Operand::Move(switch_place), - .. - } = block.terminator().kind - { - // If the block is on an unwind path, do not - // apply the optimization as unwind paths - // rely on a unique parent invariant - if block.is_cleanup { - continue 'block_iter; - } - - // If the block has fewer than 2 predecessors, ignore it - // we could maybe chain blocks that have exactly one - // predecessor, but for now we ignore that - if predecessors[block_id].len() < 2 { - continue 'block_iter; - } - - // First, let's find a non-const place - // that determines the result of the switch - if let Some(switch_place) = find_determining_place(switch_place, block) { - // We now have an input place for which it would - // be interesting if predecessors assigned it from a const - - let mut predecessors_left = predecessors[block_id].len(); - 'predec_iter: for predecessor_id in predecessors[block_id].iter().copied() { - let predecessor = &body.basic_blocks[predecessor_id]; - - // First we make sure the predecessor jumps - // in a reasonable way - match &predecessor.terminator().kind { - // The following terminators are - // unconditionally valid - TerminatorKind::Goto { .. } | TerminatorKind::SwitchInt { .. } => {} - - TerminatorKind::FalseEdge { real_target, .. } => { - if *real_target != block_id { - continue 'predec_iter; - } - } - - // The following terminators are not allowed - TerminatorKind::UnwindResume - | TerminatorKind::Drop { .. } - | TerminatorKind::Call { .. } - | TerminatorKind::Assert { .. } - | TerminatorKind::FalseUnwind { .. } - | TerminatorKind::Yield { .. } - | TerminatorKind::UnwindTerminate(_) - | TerminatorKind::Return - | TerminatorKind::Unreachable - | TerminatorKind::InlineAsm { .. } - | TerminatorKind::CoroutineDrop => { - continue 'predec_iter; - } - } - - if is_likely_const(switch_place, predecessor) { - new_blocks.push((predecessor_id, block_id)); - predecessors_left -= 1; - if predecessors_left < 2 { - // If the original block only has one predecessor left, - // we have nothing left to do - break 'predec_iter; - } - } - } - } - } - } - - // Once the analysis is done, perform the duplication - let body_span = body.span; - let copied_blocks = new_blocks.len(); - let blocks = body.basic_blocks_mut(); - for (pred_id, target_id) in new_blocks { - let new_block = blocks[target_id].clone(); - let new_block_id = blocks.push(new_block); - let terminator = blocks[pred_id].terminator_mut(); - - match terminator.kind { - TerminatorKind::Goto { ref mut target } => { - *target = new_block_id; - } - - TerminatorKind::FalseEdge { ref mut real_target, .. } => { - if *real_target == target_id { - *real_target = new_block_id; - } - } - - TerminatorKind::SwitchInt { ref mut targets, .. } => { - targets.all_targets_mut().iter_mut().for_each(|x| { - if *x == target_id { - *x = new_block_id; - } - }); - } - - TerminatorKind::UnwindResume - | TerminatorKind::UnwindTerminate(_) - | TerminatorKind::Return - | TerminatorKind::Unreachable - | TerminatorKind::CoroutineDrop - | TerminatorKind::Assert { .. } - | TerminatorKind::FalseUnwind { .. } - | TerminatorKind::Drop { .. } - | TerminatorKind::Call { .. } - | TerminatorKind::InlineAsm { .. } - | TerminatorKind::Yield { .. } => { - span_bug!( - body_span, - "basic block terminator had unexpected kind {:?}", - &terminator.kind - ) - } - } - } - - copied_blocks -} - -/// This function describes a rough heuristic guessing -/// whether a place is last set with a const within the block. -/// Notably, it will be overly pessimistic in cases that are already -/// not handled by `separate_const_switch`. -fn is_likely_const<'tcx>(mut tracked_place: Place<'tcx>, block: &BasicBlockData<'tcx>) -> bool { - for statement in block.statements.iter().rev() { - match &statement.kind { - StatementKind::Assign(assign) => { - if assign.0 == tracked_place { - match assign.1 { - // These rvalues are definitely constant - Rvalue::Use(Operand::Constant(_)) - | Rvalue::Ref(_, _, _) - | Rvalue::AddressOf(_, _) - | Rvalue::Cast(_, Operand::Constant(_), _) - | Rvalue::NullaryOp(_, _) - | Rvalue::ShallowInitBox(_, _) - | Rvalue::UnaryOp(_, Operand::Constant(_)) => return true, - - // These rvalues make things ambiguous - Rvalue::Repeat(_, _) - | Rvalue::ThreadLocalRef(_) - | Rvalue::Len(_) - | Rvalue::BinaryOp(_, _) - | Rvalue::CheckedBinaryOp(_, _) - | Rvalue::Aggregate(_, _) => return false, - - // These rvalues move the place to track - Rvalue::Cast(_, Operand::Copy(place) | Operand::Move(place), _) - | Rvalue::Use(Operand::Copy(place) | Operand::Move(place)) - | Rvalue::CopyForDeref(place) - | Rvalue::UnaryOp(_, Operand::Copy(place) | Operand::Move(place)) - | Rvalue::Discriminant(place) => tracked_place = place, - } - } - } - - // If the discriminant is set, it is always set - // as a constant, so the job is done. - // As we are **ignoring projections**, if the place - // we are tracking sees its discriminant be set, - // that means we had to be tracking the discriminant - // specifically (as it is impossible to switch over - // an enum directly, and if we were switching over - // its content, we would have had to at least cast it to - // some variant first) - StatementKind::SetDiscriminant { place, .. } => { - if **place == tracked_place { - return true; - } - } - - // These statements have no influence on the place - // we are interested in - StatementKind::FakeRead(_) - | StatementKind::Deinit(_) - | StatementKind::StorageLive(_) - | StatementKind::Retag(_, _) - | StatementKind::AscribeUserType(_, _) - | StatementKind::PlaceMention(..) - | StatementKind::Coverage(_) - | StatementKind::StorageDead(_) - | StatementKind::Intrinsic(_) - | StatementKind::ConstEvalCounter - | StatementKind::Nop => {} - } - } - - // If no good reason for the place to be const is found, - // give up. We could maybe go up predecessors, but in - // most cases giving up now should be sufficient. - false -} - -/// Finds a unique place that entirely determines the value -/// of `switch_place`, if it exists. This is only a heuristic. -/// Ideally we would like to track multiple determining places -/// for some edge cases, but one is enough for a lot of situations. -fn find_determining_place<'tcx>( - mut switch_place: Place<'tcx>, - block: &BasicBlockData<'tcx>, -) -> Option> { - for statement in block.statements.iter().rev() { - match &statement.kind { - StatementKind::Assign(op) => { - if op.0 != switch_place { - continue; - } - - match op.1 { - // The following rvalues move the place - // that may be const in the predecessor - Rvalue::Use(Operand::Move(new) | Operand::Copy(new)) - | Rvalue::UnaryOp(_, Operand::Copy(new) | Operand::Move(new)) - | Rvalue::CopyForDeref(new) - | Rvalue::Cast(_, Operand::Move(new) | Operand::Copy(new), _) - | Rvalue::Repeat(Operand::Move(new) | Operand::Copy(new), _) - | Rvalue::Discriminant(new) - => switch_place = new, - - // The following rvalues might still make the block - // be valid but for now we reject them - Rvalue::Len(_) - | Rvalue::Ref(_, _, _) - | Rvalue::BinaryOp(_, _) - | Rvalue::CheckedBinaryOp(_, _) - | Rvalue::Aggregate(_, _) - - // The following rvalues definitely mean we cannot - // or should not apply this optimization - | Rvalue::Use(Operand::Constant(_)) - | Rvalue::Repeat(Operand::Constant(_), _) - | Rvalue::ThreadLocalRef(_) - | Rvalue::AddressOf(_, _) - | Rvalue::NullaryOp(_, _) - | Rvalue::ShallowInitBox(_, _) - | Rvalue::UnaryOp(_, Operand::Constant(_)) - | Rvalue::Cast(_, Operand::Constant(_), _) => return None, - } - } - - // These statements have no influence on the place - // we are interested in - StatementKind::FakeRead(_) - | StatementKind::Deinit(_) - | StatementKind::StorageLive(_) - | StatementKind::StorageDead(_) - | StatementKind::Retag(_, _) - | StatementKind::AscribeUserType(_, _) - | StatementKind::PlaceMention(..) - | StatementKind::Coverage(_) - | StatementKind::Intrinsic(_) - | StatementKind::ConstEvalCounter - | StatementKind::Nop => {} - - // If the discriminant is set, it is always set - // as a constant, so the job is already done. - // As we are **ignoring projections**, if the place - // we are tracking sees its discriminant be set, - // that means we had to be tracking the discriminant - // specifically (as it is impossible to switch over - // an enum directly, and if we were switching over - // its content, we would have had to at least cast it to - // some variant first) - StatementKind::SetDiscriminant { place, .. } => { - if **place == switch_place { - return None; - } - } - } - } - - Some(switch_place) -} diff --git a/tests/mir-opt/const_goto.issue_77355_opt.ConstGoto.diff b/tests/mir-opt/const_goto.issue_77355_opt.ConstGoto.diff deleted file mode 100644 index 43bdb431129..00000000000 --- a/tests/mir-opt/const_goto.issue_77355_opt.ConstGoto.diff +++ /dev/null @@ -1,50 +0,0 @@ -- // MIR for `issue_77355_opt` before ConstGoto -+ // MIR for `issue_77355_opt` after ConstGoto - - fn issue_77355_opt(_1: Foo) -> u64 { - debug num => _1; - let mut _0: u64; -- let mut _2: bool; -- let mut _3: isize; -+ let mut _2: isize; - - bb0: { -- StorageLive(_2); -- _3 = discriminant(_1); -- switchInt(move _3) -> [1: bb2, 2: bb2, otherwise: bb1]; -+ _2 = discriminant(_1); -+ switchInt(move _2) -> [1: bb2, 2: bb2, otherwise: bb1]; - } - - bb1: { -- _2 = const false; -+ _0 = const 42_u64; - goto -> bb3; - } - - bb2: { -- _2 = const true; -+ _0 = const 23_u64; - goto -> bb3; - } - - bb3: { -- switchInt(move _2) -> [0: bb5, otherwise: bb4]; -- } -- -- bb4: { -- _0 = const 23_u64; -- goto -> bb6; -- } -- -- bb5: { -- _0 = const 42_u64; -- goto -> bb6; -- } -- -- bb6: { -- StorageDead(_2); - return; - } - } - diff --git a/tests/mir-opt/const_goto.rs b/tests/mir-opt/const_goto.rs deleted file mode 100644 index 93cb71c3a0f..00000000000 --- a/tests/mir-opt/const_goto.rs +++ /dev/null @@ -1,19 +0,0 @@ -// skip-filecheck -// unit-test: ConstGoto - -pub enum Foo { - A, - B, - C, - D, - E, - F, -} - -// EMIT_MIR const_goto.issue_77355_opt.ConstGoto.diff -fn issue_77355_opt(num: Foo) -> u64 { - if matches!(num, Foo::B | Foo::C) { 23 } else { 42 } -} -fn main() { - issue_77355_opt(Foo::A); -} diff --git a/tests/mir-opt/const_goto_const_eval_fail.f.ConstGoto.diff b/tests/mir-opt/const_goto_const_eval_fail.f.ConstGoto.diff deleted file mode 100644 index 84a13f28a31..00000000000 --- a/tests/mir-opt/const_goto_const_eval_fail.f.ConstGoto.diff +++ /dev/null @@ -1,51 +0,0 @@ -- // MIR for `f` before ConstGoto -+ // MIR for `f` after ConstGoto - - fn f() -> u64 { - let mut _0: u64; - let mut _1: bool; - let mut _2: i32; - - bb0: { - StorageLive(_1); - StorageLive(_2); - _2 = const A; - switchInt(_2) -> [1: bb2, 2: bb2, 3: bb2, otherwise: bb1]; - } - - bb1: { - _1 = const true; - goto -> bb3; - } - - bb2: { - _1 = const B; -- goto -> bb3; -+ switchInt(_1) -> [0: bb4, otherwise: bb3]; - } - - bb3: { -- switchInt(_1) -> [0: bb5, otherwise: bb4]; -- } -- -- bb4: { - _0 = const 2_u64; -- goto -> bb6; -+ goto -> bb5; - } - -- bb5: { -+ bb4: { - _0 = const 1_u64; -- goto -> bb6; -+ goto -> bb5; - } - -- bb6: { -+ bb5: { - StorageDead(_2); - StorageDead(_1); - return; - } - } - diff --git a/tests/mir-opt/const_goto_const_eval_fail.f.JumpThreading.diff b/tests/mir-opt/const_goto_const_eval_fail.f.JumpThreading.diff new file mode 100644 index 00000000000..4fc9254b7ba --- /dev/null +++ b/tests/mir-opt/const_goto_const_eval_fail.f.JumpThreading.diff @@ -0,0 +1,47 @@ +- // MIR for `f` before JumpThreading ++ // MIR for `f` after JumpThreading + + fn f() -> u64 { + let mut _0: u64; + let mut _1: bool; + + bb0: { + StorageLive(_1); + switchInt(const A) -> [1: bb2, 2: bb2, 3: bb2, otherwise: bb1]; + } + + bb1: { + _1 = const true; +- goto -> bb3; ++ goto -> bb7; + } + + bb2: { + _1 = const B; + goto -> bb3; + } + + bb3: { + switchInt(_1) -> [0: bb5, otherwise: bb4]; + } + + bb4: { + _0 = const 2_u64; + goto -> bb6; + } + + bb5: { + _0 = const 1_u64; + goto -> bb6; + } + + bb6: { + StorageDead(_1); + return; ++ } ++ ++ bb7: { ++ goto -> bb4; + } + } + diff --git a/tests/mir-opt/const_goto_const_eval_fail.rs b/tests/mir-opt/const_goto_const_eval_fail.rs index 869f916001c..c0e8e144b15 100644 --- a/tests/mir-opt/const_goto_const_eval_fail.rs +++ b/tests/mir-opt/const_goto_const_eval_fail.rs @@ -5,7 +5,7 @@ // compile-flags: -Zunsound-mir-opts // If const eval fails, then don't crash -// EMIT_MIR const_goto_const_eval_fail.f.ConstGoto.diff +// EMIT_MIR const_goto_const_eval_fail.f.JumpThreading.diff pub fn f() -> u64 { match { match A { diff --git a/tests/mir-opt/const_goto_storage.match_nested_if.ConstGoto.diff b/tests/mir-opt/const_goto_storage.match_nested_if.ConstGoto.diff deleted file mode 100644 index 1768298d521..00000000000 --- a/tests/mir-opt/const_goto_storage.match_nested_if.ConstGoto.diff +++ /dev/null @@ -1,102 +0,0 @@ -- // MIR for `match_nested_if` before ConstGoto -+ // MIR for `match_nested_if` after ConstGoto - - fn match_nested_if() -> bool { - let mut _0: bool; - let _1: bool; -- let mut _2: (); -- let mut _3: bool; -- let mut _4: bool; -- let mut _5: bool; -- let mut _6: bool; -+ let mut _2: bool; - scope 1 { - debug val => _1; - } - - bb0: { - StorageLive(_1); - StorageLive(_2); -- _2 = (); -- StorageLive(_3); -- StorageLive(_4); -- StorageLive(_5); -- StorageLive(_6); -- _6 = const true; -- switchInt(move _6) -> [0: bb2, otherwise: bb1]; -+ _2 = const true; -+ switchInt(move _2) -> [0: bb2, otherwise: bb1]; - } - - bb1: { -- _5 = const true; -+ StorageDead(_2); -+ _1 = const true; - goto -> bb3; - } - - bb2: { -- _5 = const false; -+ StorageDead(_2); -+ _1 = const false; - goto -> bb3; - } - - bb3: { -- switchInt(move _5) -> [0: bb5, otherwise: bb4]; -- } -- -- bb4: { -- StorageDead(_6); -- _4 = const true; -- goto -> bb6; -- } -- -- bb5: { -- StorageDead(_6); -- _4 = const false; -- goto -> bb6; -- } -- -- bb6: { -- switchInt(move _4) -> [0: bb8, otherwise: bb7]; -- } -- -- bb7: { -- StorageDead(_5); -- _3 = const true; -- goto -> bb9; -- } -- -- bb8: { -- StorageDead(_5); -- _3 = const false; -- goto -> bb9; -- } -- -- bb9: { -- switchInt(move _3) -> [0: bb11, otherwise: bb10]; -- } -- -- bb10: { -- StorageDead(_4); -- StorageDead(_3); -- _1 = const true; -- goto -> bb12; -- } -- -- bb11: { -- StorageDead(_4); -- StorageDead(_3); -- _1 = const false; -- goto -> bb12; -- } -- -- bb12: { -- StorageDead(_2); - _0 = _1; - StorageDead(_1); - return; - } - } - diff --git a/tests/mir-opt/const_goto_storage.rs b/tests/mir-opt/const_goto_storage.rs deleted file mode 100644 index 9d43da23990..00000000000 --- a/tests/mir-opt/const_goto_storage.rs +++ /dev/null @@ -1,22 +0,0 @@ -// skip-filecheck -// unit-test: ConstGoto - -// EMIT_MIR const_goto_storage.match_nested_if.ConstGoto.diff -fn match_nested_if() -> bool { - let val = match () { - () if if if if true { true } else { false } { true } else { false } { - true - } else { - false - } => - { - true - } - _ => false, - }; - val -} - -fn main() { - let _ = match_nested_if(); -} diff --git a/tests/mir-opt/pre-codegen/matches_macro.issue_77355_opt.PreCodegen.after.mir b/tests/mir-opt/pre-codegen/matches_macro.issue_77355_opt.PreCodegen.after.mir new file mode 100644 index 00000000000..d41135c6a4f --- /dev/null +++ b/tests/mir-opt/pre-codegen/matches_macro.issue_77355_opt.PreCodegen.after.mir @@ -0,0 +1,22 @@ +// MIR for `issue_77355_opt` after PreCodegen + +fn issue_77355_opt(_1: Foo) -> u64 { + debug num => _1; + let mut _0: u64; + let mut _2: isize; + + bb0: { + _2 = discriminant(_1); + switchInt(move _2) -> [1: bb1, 2: bb1, otherwise: bb2]; + } + + bb1: { + _0 = const 23_u64; + return; + } + + bb2: { + _0 = const 42_u64; + return; + } +} diff --git a/tests/mir-opt/pre-codegen/matches_macro.rs b/tests/mir-opt/pre-codegen/matches_macro.rs new file mode 100644 index 00000000000..42de2296571 --- /dev/null +++ b/tests/mir-opt/pre-codegen/matches_macro.rs @@ -0,0 +1,27 @@ +// This test verifies that the MIR we output using the `matches!()` macro is close +// to the MIR for an `if let` branch. + +pub enum Foo { + A, + B, + C, + D, + E, + F, +} + +// EMIT_MIR matches_macro.issue_77355_opt.PreCodegen.after.mir +fn issue_77355_opt(num: Foo) -> u64 { + // CHECK-LABEL: fn issue_77355_opt( + // CHECK: switchInt({{.*}}) -> [1: bb1, 2: bb1, otherwise: bb2]; + // CHECK: bb1: { + // CHECK-NEXT: _0 = const 23_u64; + // CHECK-NEXT: return; + // CHECK: bb2: { + // CHECK-NEXT: _0 = const 42_u64; + // CHECK-NEXT: return; + if matches!(num, Foo::B | Foo::C) { 23 } else { 42 } +} +fn main() { + issue_77355_opt(Foo::A); +} diff --git a/tests/mir-opt/separate_const_switch.identity.SeparateConstSwitch.diff b/tests/mir-opt/separate_const_switch.identity.JumpThreading.diff similarity index 87% rename from tests/mir-opt/separate_const_switch.identity.SeparateConstSwitch.diff rename to tests/mir-opt/separate_const_switch.identity.JumpThreading.diff index d2731615284..ab3d91ab918 100644 --- a/tests/mir-opt/separate_const_switch.identity.SeparateConstSwitch.diff +++ b/tests/mir-opt/separate_const_switch.identity.JumpThreading.diff @@ -1,5 +1,5 @@ -- // MIR for `identity` before SeparateConstSwitch -+ // MIR for `identity` after SeparateConstSwitch +- // MIR for `identity` before JumpThreading ++ // MIR for `identity` after JumpThreading fn identity(_1: Result) -> Result { debug x => _1; @@ -79,7 +79,8 @@ StorageDead(_8); StorageDead(_3); _4 = discriminant(_2); - switchInt(move _4) -> [0: bb1, 1: bb2, otherwise: bb6]; +- switchInt(move _4) -> [0: bb1, 1: bb2, otherwise: bb6]; ++ goto -> bb1; } bb4: { @@ -88,7 +89,8 @@ _11 = Result::::Err(_10); _2 = ControlFlow::, i32>::Break(move _11); StorageDead(_11); - goto -> bb3; +- goto -> bb3; ++ goto -> bb7; } bb5: { @@ -99,6 +101,15 @@ bb6: { unreachable; ++ } ++ ++ bb7: { ++ StorageDead(_10); ++ StorageDead(_9); ++ StorageDead(_8); ++ StorageDead(_3); ++ _4 = discriminant(_2); ++ goto -> bb2; } } diff --git a/tests/mir-opt/separate_const_switch.rs b/tests/mir-opt/separate_const_switch.rs index 3f43cdf4350..bad61d97475 100644 --- a/tests/mir-opt/separate_const_switch.rs +++ b/tests/mir-opt/separate_const_switch.rs @@ -6,7 +6,7 @@ use std::ops::ControlFlow; -// EMIT_MIR separate_const_switch.too_complex.SeparateConstSwitch.diff +// EMIT_MIR separate_const_switch.too_complex.JumpThreading.diff fn too_complex(x: Result) -> Option { // The pass should break the outer match into // two blocks that only have one parent each. @@ -23,7 +23,7 @@ fn too_complex(x: Result) -> Option { } } -// EMIT_MIR separate_const_switch.identity.SeparateConstSwitch.diff +// EMIT_MIR separate_const_switch.identity.JumpThreading.diff fn identity(x: Result) -> Result { Ok(x?) } diff --git a/tests/mir-opt/separate_const_switch.too_complex.SeparateConstSwitch.diff b/tests/mir-opt/separate_const_switch.too_complex.JumpThreading.diff similarity index 83% rename from tests/mir-opt/separate_const_switch.too_complex.SeparateConstSwitch.diff rename to tests/mir-opt/separate_const_switch.too_complex.JumpThreading.diff index 294bfa661cf..1ac527e9338 100644 --- a/tests/mir-opt/separate_const_switch.too_complex.SeparateConstSwitch.diff +++ b/tests/mir-opt/separate_const_switch.too_complex.JumpThreading.diff @@ -1,5 +1,5 @@ -- // MIR for `too_complex` before SeparateConstSwitch -+ // MIR for `too_complex` after SeparateConstSwitch +- // MIR for `too_complex` before JumpThreading ++ // MIR for `too_complex` after JumpThreading fn too_complex(_1: Result) -> Option { debug x => _1; @@ -33,7 +33,8 @@ bb1: { _5 = ((_1 as Err).0: usize); _2 = ControlFlow::::Break(_5); - goto -> bb3; +- goto -> bb3; ++ goto -> bb8; } bb2: { @@ -44,7 +45,8 @@ bb3: { _6 = discriminant(_2); - switchInt(move _6) -> [0: bb5, 1: bb4, otherwise: bb7]; +- switchInt(move _6) -> [0: bb5, 1: bb4, otherwise: bb7]; ++ goto -> bb5; } bb4: { @@ -68,6 +70,11 @@ bb7: { unreachable; ++ } ++ ++ bb8: { ++ _6 = discriminant(_2); ++ goto -> bb4; } }