diff --git a/compiler/rustc_mir/src/transform/mod.rs b/compiler/rustc_mir/src/transform/mod.rs index 5c201594ddd89..bbe83aa3bd8ad 100644 --- a/compiler/rustc_mir/src/transform/mod.rs +++ b/compiler/rustc_mir/src/transform/mod.rs @@ -48,6 +48,7 @@ pub mod remove_unneeded_drops; pub mod remove_zsts; pub mod required_consts; pub mod rustc_peek; +pub mod separate_const_switch; pub mod simplify; pub mod simplify_branches; pub mod simplify_comparison_integral; @@ -501,6 +502,7 @@ fn run_optimization_passes<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { // inst combine is after MatchBranchSimplification to clean up Ne(_1, false) &multiple_return_terminators::MultipleReturnTerminators, &instcombine::InstCombine, + &separate_const_switch::SeparateConstSwitch, &const_prop::ConstProp, &simplify_branches::SimplifyBranches::new("after-const-prop"), &early_otherwise_branch::EarlyOtherwiseBranch, diff --git a/compiler/rustc_mir/src/transform/separate_const_switch.rs b/compiler/rustc_mir/src/transform/separate_const_switch.rs new file mode 100644 index 0000000000000..87cd27984a073 --- /dev/null +++ b/compiler/rustc_mir/src/transform/separate_const_switch.rs @@ -0,0 +1,343 @@ +//! 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 crate::transform::MirPass; +use rustc_middle::mir::*; +use rustc_middle::ty::TyCtxt; +use smallvec::SmallVec; + +pub struct SeparateConstSwitch; + +impl<'tcx> MirPass<'tcx> for SeparateConstSwitch { + fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) { + if tcx.sess.mir_opt_level() < 4 { + return; + } + + // 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(tcx, body); + } + } +} + +/// Returns the amount of blocks that were duplicated +pub fn separate_const_switch<'tcx>(body: &mut Body<'tcx>) -> usize { + let mut new_blocks: SmallVec<[(BasicBlock, BasicBlock); 6]> = SmallVec::new(); + let predecessors = body.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::Resume + | TerminatorKind::Drop { .. } + | TerminatorKind::DropAndReplace { .. } + | TerminatorKind::Call { .. } + | TerminatorKind::Assert { .. } + | TerminatorKind::FalseUnwind { .. } + | TerminatorKind::Yield { .. } + | TerminatorKind::Abort + | TerminatorKind::Return + | TerminatorKind::Unreachable + | TerminatorKind::InlineAsm { .. } + | TerminatorKind::GeneratorDrop => { + 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::Resume + | TerminatorKind::Abort + | TerminatorKind::Return + | TerminatorKind::Unreachable + | TerminatorKind::GeneratorDrop + | TerminatorKind::Assert { .. } + | TerminatorKind::DropAndReplace { .. } + | 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::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::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; + } + } + + // If inline assembly is found, we probably should + // not try to analyze the code + StatementKind::LlvmInlineAsm(_) => return false, + + // These statements have no influence on the place + // we are interested in + StatementKind::FakeRead(_) + | StatementKind::StorageLive(_) + | StatementKind::Retag(_, _) + | StatementKind::AscribeUserType(_, _) + | StatementKind::Coverage(_) + | StatementKind::StorageDead(_) + | StatementKind::CopyNonOverlapping(_) + | 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::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::UnaryOp(_, Operand::Constant(_)) + | Rvalue::Cast(_, Operand::Constant(_), _) + => return None, + } + } + + // These statements have no influence on the place + // we are interested in + StatementKind::FakeRead(_) + | StatementKind::StorageLive(_) + | StatementKind::StorageDead(_) + | StatementKind::Retag(_, _) + | StatementKind::AscribeUserType(_, _) + | StatementKind::Coverage(_) + | StatementKind::CopyNonOverlapping(_) + | StatementKind::Nop => {} + + // If inline assembly is found, we probably should + // not try to analyze the code + StatementKind::LlvmInlineAsm(_) => return None, + + // 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/src/test/mir-opt/separate_const_switch.identity.ConstProp.diff b/src/test/mir-opt/separate_const_switch.identity.ConstProp.diff new file mode 100644 index 0000000000000..57299cee7b726 --- /dev/null +++ b/src/test/mir-opt/separate_const_switch.identity.ConstProp.diff @@ -0,0 +1,140 @@ +- // MIR for `identity` before ConstProp ++ // MIR for `identity` after ConstProp + + fn identity(_1: Result) -> Result { + debug x => _1; // in scope 0 at $DIR/separate_const_switch.rs:28:13: 28:14 + let mut _0: std::result::Result; // return place in scope 0 at $DIR/separate_const_switch.rs:28:37: 28:53 + let mut _2: i32; // in scope 0 at $DIR/separate_const_switch.rs:29:8: 29:10 + let mut _3: std::ops::ControlFlow, i32>; // in scope 0 at $DIR/separate_const_switch.rs:29:8: 29:10 + let mut _4: std::result::Result; // in scope 0 at $DIR/separate_const_switch.rs:29:8: 29:9 + let mut _5: isize; // in scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 + let _6: std::result::Result; // in scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 + let mut _7: !; // in scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 + let mut _8: std::result::Result; // in scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 + let _9: i32; // in scope 0 at $DIR/separate_const_switch.rs:29:8: 29:10 + scope 1 { + debug residual => _6; // in scope 1 at $DIR/separate_const_switch.rs:29:9: 29:10 + scope 2 { + scope 8 (inlined as FromResidual>>::from_residual) { // at $DIR/separate_const_switch.rs:29:8: 29:10 + debug residual => _8; // in scope 8 at $DIR/separate_const_switch.rs:29:8: 29:10 + let _16: i32; // in scope 8 at $DIR/separate_const_switch.rs:29:8: 29:10 + let mut _17: i32; // in scope 8 at $DIR/separate_const_switch.rs:29:8: 29:10 + let mut _18: i32; // in scope 8 at $DIR/separate_const_switch.rs:29:8: 29:10 + scope 9 { + debug e => _16; // in scope 9 at $DIR/separate_const_switch.rs:29:8: 29:10 + scope 10 (inlined >::from) { // at $DIR/separate_const_switch.rs:29:8: 29:10 + debug t => _18; // in scope 10 at $DIR/separate_const_switch.rs:29:8: 29:10 + } + } + } + } + } + scope 3 { + debug val => _9; // in scope 3 at $DIR/separate_const_switch.rs:29:8: 29:10 + scope 4 { + } + } + scope 5 (inlined as Try>::branch) { // at $DIR/separate_const_switch.rs:29:8: 29:10 + debug self => _4; // in scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + let mut _10: isize; // in scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + let _11: i32; // in scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + let mut _12: i32; // in scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + let _13: i32; // in scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + let mut _14: std::result::Result; // in scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + let mut _15: i32; // in scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + scope 6 { + debug v => _11; // in scope 6 at $DIR/separate_const_switch.rs:29:8: 29:10 + } + scope 7 { + debug e => _13; // in scope 7 at $DIR/separate_const_switch.rs:29:8: 29:10 + } + } + + bb0: { + StorageLive(_2); // scope 0 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageLive(_3); // scope 0 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageLive(_4); // scope 0 at $DIR/separate_const_switch.rs:29:8: 29:9 + _4 = _1; // scope 0 at $DIR/separate_const_switch.rs:29:8: 29:9 + StorageLive(_10); // scope 0 at $DIR/separate_const_switch.rs:29:8: 29:10 + _10 = discriminant(_4); // scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + switchInt(move _10) -> [0_isize: bb5, 1_isize: bb3, otherwise: bb4]; // scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + } + + bb1: { + StorageLive(_9); // scope 0 at $DIR/separate_const_switch.rs:29:8: 29:10 + _9 = ((_3 as Continue).0: i32); // scope 0 at $DIR/separate_const_switch.rs:29:8: 29:10 + _2 = _9; // scope 4 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_9); // scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 + ((_0 as Ok).0: i32) = move _2; // scope 0 at $DIR/separate_const_switch.rs:29:5: 29:11 + discriminant(_0) = 0; // scope 0 at $DIR/separate_const_switch.rs:29:5: 29:11 + StorageDead(_2); // scope 0 at $DIR/separate_const_switch.rs:29:10: 29:11 + StorageDead(_3); // scope 0 at $DIR/separate_const_switch.rs:30:1: 30:2 + return; // scope 0 at $DIR/separate_const_switch.rs:30:2: 30:2 + } + + bb2: { + StorageLive(_6); // scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 + _6 = ((_3 as Break).0: std::result::Result); // scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 + StorageLive(_8); // scope 2 at $DIR/separate_const_switch.rs:29:9: 29:10 + _8 = _6; // scope 2 at $DIR/separate_const_switch.rs:29:9: 29:10 + StorageLive(_16); // scope 8 at $DIR/separate_const_switch.rs:29:8: 29:10 + _16 = move ((_8 as Err).0: i32); // scope 8 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageLive(_17); // scope 9 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageLive(_18); // scope 9 at $DIR/separate_const_switch.rs:29:8: 29:10 + _18 = move _16; // scope 9 at $DIR/separate_const_switch.rs:29:8: 29:10 + _17 = move _18; // scope 10 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_18); // scope 9 at $DIR/separate_const_switch.rs:29:8: 29:10 + ((_0 as Err).0: i32) = move _17; // scope 9 at $DIR/separate_const_switch.rs:29:8: 29:10 + discriminant(_0) = 1; // scope 9 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_17); // scope 9 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_16); // scope 8 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_8); // scope 2 at $DIR/separate_const_switch.rs:29:9: 29:10 + StorageDead(_6); // scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 + StorageDead(_2); // scope 0 at $DIR/separate_const_switch.rs:29:10: 29:11 + StorageDead(_3); // scope 0 at $DIR/separate_const_switch.rs:30:1: 30:2 + return; // scope 0 at $DIR/separate_const_switch.rs:30:2: 30:2 + } + + bb3: { + StorageLive(_13); // scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + _13 = move ((_4 as Err).0: i32); // scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageLive(_14); // scope 7 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageLive(_15); // scope 7 at $DIR/separate_const_switch.rs:29:8: 29:10 + _15 = move _13; // scope 7 at $DIR/separate_const_switch.rs:29:8: 29:10 + ((_14 as Err).0: i32) = move _15; // scope 7 at $DIR/separate_const_switch.rs:29:8: 29:10 + discriminant(_14) = 1; // scope 7 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_15); // scope 7 at $DIR/separate_const_switch.rs:29:8: 29:10 + ((_3 as Break).0: std::result::Result) = move _14; // scope 7 at $DIR/separate_const_switch.rs:29:8: 29:10 + discriminant(_3) = 1; // scope 7 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_14); // scope 7 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_13); // scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_10); // scope 0 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_4); // scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 +- _5 = discriminant(_3); // scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 +- switchInt(move _5) -> [0_isize: bb1, otherwise: bb2]; // scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 ++ _5 = const 1_isize; // scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 ++ switchInt(const 1_isize) -> [0_isize: bb1, otherwise: bb2]; // scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 + } + + bb4: { + unreachable; // scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + } + + bb5: { + StorageLive(_11); // scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + _11 = move ((_4 as Ok).0: i32); // scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageLive(_12); // scope 6 at $DIR/separate_const_switch.rs:29:8: 29:10 + _12 = move _11; // scope 6 at $DIR/separate_const_switch.rs:29:8: 29:10 + ((_3 as Continue).0: i32) = move _12; // scope 6 at $DIR/separate_const_switch.rs:29:8: 29:10 + discriminant(_3) = 0; // scope 6 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_12); // scope 6 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_11); // scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_10); // scope 0 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_4); // scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 +- _5 = discriminant(_3); // scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 +- switchInt(move _5) -> [0_isize: bb1, otherwise: bb2]; // scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 ++ _5 = const 0_isize; // scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 ++ switchInt(const 0_isize) -> [0_isize: bb1, otherwise: bb2]; // scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 + } + } + diff --git a/src/test/mir-opt/separate_const_switch.identity.PreCodegen.after.mir b/src/test/mir-opt/separate_const_switch.identity.PreCodegen.after.mir new file mode 100644 index 0000000000000..dee45c5840383 --- /dev/null +++ b/src/test/mir-opt/separate_const_switch.identity.PreCodegen.after.mir @@ -0,0 +1,122 @@ +// MIR for `identity` after PreCodegen + +fn identity(_1: Result) -> Result { + debug x => _1; // in scope 0 at $DIR/separate_const_switch.rs:28:13: 28:14 + let mut _0: std::result::Result; // return place in scope 0 at $DIR/separate_const_switch.rs:28:37: 28:53 + let mut _2: i32; // in scope 0 at $DIR/separate_const_switch.rs:29:8: 29:10 + let mut _3: std::ops::ControlFlow, i32>; // in scope 0 at $DIR/separate_const_switch.rs:29:8: 29:10 + let mut _4: std::result::Result; // in scope 0 at $DIR/separate_const_switch.rs:29:8: 29:9 + let _5: std::result::Result; // in scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 + let mut _6: std::result::Result; // in scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 + let _7: i32; // in scope 0 at $DIR/separate_const_switch.rs:29:8: 29:10 + scope 1 { + debug residual => _5; // in scope 1 at $DIR/separate_const_switch.rs:29:9: 29:10 + scope 2 { + scope 8 (inlined as FromResidual>>::from_residual) { // at $DIR/separate_const_switch.rs:29:8: 29:10 + debug residual => _6; // in scope 8 at $DIR/separate_const_switch.rs:29:8: 29:10 + let _14: i32; // in scope 8 at $DIR/separate_const_switch.rs:29:8: 29:10 + let mut _15: i32; // in scope 8 at $DIR/separate_const_switch.rs:29:8: 29:10 + let mut _16: i32; // in scope 8 at $DIR/separate_const_switch.rs:29:8: 29:10 + scope 9 { + debug e => _14; // in scope 9 at $DIR/separate_const_switch.rs:29:8: 29:10 + scope 10 (inlined >::from) { // at $DIR/separate_const_switch.rs:29:8: 29:10 + debug t => _16; // in scope 10 at $DIR/separate_const_switch.rs:29:8: 29:10 + } + } + } + } + } + scope 3 { + debug val => _7; // in scope 3 at $DIR/separate_const_switch.rs:29:8: 29:10 + scope 4 { + } + } + scope 5 (inlined as Try>::branch) { // at $DIR/separate_const_switch.rs:29:8: 29:10 + debug self => _4; // in scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + let mut _8: isize; // in scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + let _9: i32; // in scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + let mut _10: i32; // in scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + let _11: i32; // in scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + let mut _12: std::result::Result; // in scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + let mut _13: i32; // in scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + scope 6 { + debug v => _9; // in scope 6 at $DIR/separate_const_switch.rs:29:8: 29:10 + } + scope 7 { + debug e => _11; // in scope 7 at $DIR/separate_const_switch.rs:29:8: 29:10 + } + } + + bb0: { + StorageLive(_2); // scope 0 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageLive(_3); // scope 0 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageLive(_4); // scope 0 at $DIR/separate_const_switch.rs:29:8: 29:9 + _4 = _1; // scope 0 at $DIR/separate_const_switch.rs:29:8: 29:9 + StorageLive(_8); // scope 0 at $DIR/separate_const_switch.rs:29:8: 29:10 + _8 = discriminant(_4); // scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + switchInt(move _8) -> [0_isize: bb3, 1_isize: bb1, otherwise: bb2]; // scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + } + + bb1: { + StorageLive(_11); // scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + _11 = move ((_4 as Err).0: i32); // scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageLive(_12); // scope 7 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageLive(_13); // scope 7 at $DIR/separate_const_switch.rs:29:8: 29:10 + _13 = move _11; // scope 7 at $DIR/separate_const_switch.rs:29:8: 29:10 + ((_12 as Err).0: i32) = move _13; // scope 7 at $DIR/separate_const_switch.rs:29:8: 29:10 + discriminant(_12) = 1; // scope 7 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_13); // scope 7 at $DIR/separate_const_switch.rs:29:8: 29:10 + ((_3 as Break).0: std::result::Result) = move _12; // scope 7 at $DIR/separate_const_switch.rs:29:8: 29:10 + discriminant(_3) = 1; // scope 7 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_12); // scope 7 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_11); // scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_8); // scope 0 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_4); // scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 + StorageLive(_5); // scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 + _5 = ((_3 as Break).0: std::result::Result); // scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 + StorageLive(_6); // scope 2 at $DIR/separate_const_switch.rs:29:9: 29:10 + _6 = _5; // scope 2 at $DIR/separate_const_switch.rs:29:9: 29:10 + StorageLive(_14); // scope 8 at $DIR/separate_const_switch.rs:29:8: 29:10 + _14 = move ((_6 as Err).0: i32); // scope 8 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageLive(_15); // scope 9 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageLive(_16); // scope 9 at $DIR/separate_const_switch.rs:29:8: 29:10 + _16 = move _14; // scope 9 at $DIR/separate_const_switch.rs:29:8: 29:10 + _15 = move _16; // scope 10 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_16); // scope 9 at $DIR/separate_const_switch.rs:29:8: 29:10 + ((_0 as Err).0: i32) = move _15; // scope 9 at $DIR/separate_const_switch.rs:29:8: 29:10 + discriminant(_0) = 1; // scope 9 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_15); // scope 9 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_14); // scope 8 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_6); // scope 2 at $DIR/separate_const_switch.rs:29:9: 29:10 + StorageDead(_5); // scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 + StorageDead(_2); // scope 0 at $DIR/separate_const_switch.rs:29:10: 29:11 + StorageDead(_3); // scope 0 at $DIR/separate_const_switch.rs:30:1: 30:2 + return; // scope 0 at $DIR/separate_const_switch.rs:30:2: 30:2 + } + + bb2: { + unreachable; // scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + } + + bb3: { + StorageLive(_9); // scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + _9 = move ((_4 as Ok).0: i32); // scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageLive(_10); // scope 6 at $DIR/separate_const_switch.rs:29:8: 29:10 + _10 = move _9; // scope 6 at $DIR/separate_const_switch.rs:29:8: 29:10 + ((_3 as Continue).0: i32) = move _10; // scope 6 at $DIR/separate_const_switch.rs:29:8: 29:10 + discriminant(_3) = 0; // scope 6 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_10); // scope 6 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_9); // scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_8); // scope 0 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_4); // scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 + StorageLive(_7); // scope 0 at $DIR/separate_const_switch.rs:29:8: 29:10 + _7 = ((_3 as Continue).0: i32); // scope 0 at $DIR/separate_const_switch.rs:29:8: 29:10 + _2 = _7; // scope 4 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_7); // scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 + ((_0 as Ok).0: i32) = move _2; // scope 0 at $DIR/separate_const_switch.rs:29:5: 29:11 + discriminant(_0) = 0; // scope 0 at $DIR/separate_const_switch.rs:29:5: 29:11 + StorageDead(_2); // scope 0 at $DIR/separate_const_switch.rs:29:10: 29:11 + StorageDead(_3); // scope 0 at $DIR/separate_const_switch.rs:30:1: 30:2 + return; // scope 0 at $DIR/separate_const_switch.rs:30:2: 30:2 + } +} diff --git a/src/test/mir-opt/separate_const_switch.identity.SeparateConstSwitch.diff b/src/test/mir-opt/separate_const_switch.identity.SeparateConstSwitch.diff new file mode 100644 index 0000000000000..4bfd0842db084 --- /dev/null +++ b/src/test/mir-opt/separate_const_switch.identity.SeparateConstSwitch.diff @@ -0,0 +1,150 @@ +- // MIR for `identity` before SeparateConstSwitch ++ // MIR for `identity` after SeparateConstSwitch + + fn identity(_1: Result) -> Result { + debug x => _1; // in scope 0 at $DIR/separate_const_switch.rs:28:13: 28:14 + let mut _0: std::result::Result; // return place in scope 0 at $DIR/separate_const_switch.rs:28:37: 28:53 + let mut _2: i32; // in scope 0 at $DIR/separate_const_switch.rs:29:8: 29:10 + let mut _3: std::ops::ControlFlow, i32>; // in scope 0 at $DIR/separate_const_switch.rs:29:8: 29:10 + let mut _4: std::result::Result; // in scope 0 at $DIR/separate_const_switch.rs:29:8: 29:9 + let mut _5: isize; // in scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 + let _6: std::result::Result; // in scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 + let mut _7: !; // in scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 + let mut _8: std::result::Result; // in scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 + let _9: i32; // in scope 0 at $DIR/separate_const_switch.rs:29:8: 29:10 + scope 1 { + debug residual => _6; // in scope 1 at $DIR/separate_const_switch.rs:29:9: 29:10 + scope 2 { + scope 8 (inlined as FromResidual>>::from_residual) { // at $DIR/separate_const_switch.rs:29:8: 29:10 + debug residual => _8; // in scope 8 at $DIR/separate_const_switch.rs:29:8: 29:10 + let _16: i32; // in scope 8 at $DIR/separate_const_switch.rs:29:8: 29:10 + let mut _17: i32; // in scope 8 at $DIR/separate_const_switch.rs:29:8: 29:10 + let mut _18: i32; // in scope 8 at $DIR/separate_const_switch.rs:29:8: 29:10 + scope 9 { + debug e => _16; // in scope 9 at $DIR/separate_const_switch.rs:29:8: 29:10 + scope 10 (inlined >::from) { // at $DIR/separate_const_switch.rs:29:8: 29:10 + debug t => _18; // in scope 10 at $DIR/separate_const_switch.rs:29:8: 29:10 + } + } + } + } + } + scope 3 { + debug val => _9; // in scope 3 at $DIR/separate_const_switch.rs:29:8: 29:10 + scope 4 { + } + } + scope 5 (inlined as Try>::branch) { // at $DIR/separate_const_switch.rs:29:8: 29:10 + debug self => _4; // in scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + let mut _10: isize; // in scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + let _11: i32; // in scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + let mut _12: i32; // in scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + let _13: i32; // in scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + let mut _14: std::result::Result; // in scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + let mut _15: i32; // in scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + scope 6 { + debug v => _11; // in scope 6 at $DIR/separate_const_switch.rs:29:8: 29:10 + } + scope 7 { + debug e => _13; // in scope 7 at $DIR/separate_const_switch.rs:29:8: 29:10 + } + } + + bb0: { + StorageLive(_2); // scope 0 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageLive(_3); // scope 0 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageLive(_4); // scope 0 at $DIR/separate_const_switch.rs:29:8: 29:9 + _4 = _1; // scope 0 at $DIR/separate_const_switch.rs:29:8: 29:9 + StorageLive(_10); // scope 0 at $DIR/separate_const_switch.rs:29:8: 29:10 + _10 = discriminant(_4); // scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 +- switchInt(move _10) -> [0_isize: bb6, 1_isize: bb4, otherwise: bb5]; // scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 ++ switchInt(move _10) -> [0_isize: bb5, 1_isize: bb3, otherwise: bb4]; // scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + } + + bb1: { +- StorageDead(_10); // scope 0 at $DIR/separate_const_switch.rs:29:8: 29:10 +- StorageDead(_4); // scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 +- _5 = discriminant(_3); // scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 +- switchInt(move _5) -> [0_isize: bb2, otherwise: bb3]; // scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 +- } +- +- bb2: { + StorageLive(_9); // scope 0 at $DIR/separate_const_switch.rs:29:8: 29:10 + _9 = ((_3 as Continue).0: i32); // scope 0 at $DIR/separate_const_switch.rs:29:8: 29:10 + _2 = _9; // scope 4 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_9); // scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 + ((_0 as Ok).0: i32) = move _2; // scope 0 at $DIR/separate_const_switch.rs:29:5: 29:11 + discriminant(_0) = 0; // scope 0 at $DIR/separate_const_switch.rs:29:5: 29:11 + StorageDead(_2); // scope 0 at $DIR/separate_const_switch.rs:29:10: 29:11 + StorageDead(_3); // scope 0 at $DIR/separate_const_switch.rs:30:1: 30:2 + return; // scope 0 at $DIR/separate_const_switch.rs:30:2: 30:2 + } + +- bb3: { ++ bb2: { + StorageLive(_6); // scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 + _6 = ((_3 as Break).0: std::result::Result); // scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 + StorageLive(_8); // scope 2 at $DIR/separate_const_switch.rs:29:9: 29:10 + _8 = _6; // scope 2 at $DIR/separate_const_switch.rs:29:9: 29:10 + StorageLive(_16); // scope 8 at $DIR/separate_const_switch.rs:29:8: 29:10 + _16 = move ((_8 as Err).0: i32); // scope 8 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageLive(_17); // scope 9 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageLive(_18); // scope 9 at $DIR/separate_const_switch.rs:29:8: 29:10 + _18 = move _16; // scope 9 at $DIR/separate_const_switch.rs:29:8: 29:10 + _17 = move _18; // scope 10 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_18); // scope 9 at $DIR/separate_const_switch.rs:29:8: 29:10 + ((_0 as Err).0: i32) = move _17; // scope 9 at $DIR/separate_const_switch.rs:29:8: 29:10 + discriminant(_0) = 1; // scope 9 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_17); // scope 9 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_16); // scope 8 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_8); // scope 2 at $DIR/separate_const_switch.rs:29:9: 29:10 + StorageDead(_6); // scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 + StorageDead(_2); // scope 0 at $DIR/separate_const_switch.rs:29:10: 29:11 + StorageDead(_3); // scope 0 at $DIR/separate_const_switch.rs:30:1: 30:2 + return; // scope 0 at $DIR/separate_const_switch.rs:30:2: 30:2 + } + +- bb4: { ++ bb3: { + StorageLive(_13); // scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + _13 = move ((_4 as Err).0: i32); // scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageLive(_14); // scope 7 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageLive(_15); // scope 7 at $DIR/separate_const_switch.rs:29:8: 29:10 + _15 = move _13; // scope 7 at $DIR/separate_const_switch.rs:29:8: 29:10 + ((_14 as Err).0: i32) = move _15; // scope 7 at $DIR/separate_const_switch.rs:29:8: 29:10 + discriminant(_14) = 1; // scope 7 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_15); // scope 7 at $DIR/separate_const_switch.rs:29:8: 29:10 + ((_3 as Break).0: std::result::Result) = move _14; // scope 7 at $DIR/separate_const_switch.rs:29:8: 29:10 + discriminant(_3) = 1; // scope 7 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_14); // scope 7 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_13); // scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 +- goto -> bb1; // scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 ++ StorageDead(_10); // scope 0 at $DIR/separate_const_switch.rs:29:8: 29:10 ++ StorageDead(_4); // scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 ++ _5 = discriminant(_3); // scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 ++ switchInt(move _5) -> [0_isize: bb1, otherwise: bb2]; // scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 + } + +- bb5: { ++ bb4: { + unreachable; // scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + } + +- bb6: { ++ bb5: { + StorageLive(_11); // scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + _11 = move ((_4 as Ok).0: i32); // scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageLive(_12); // scope 6 at $DIR/separate_const_switch.rs:29:8: 29:10 + _12 = move _11; // scope 6 at $DIR/separate_const_switch.rs:29:8: 29:10 + ((_3 as Continue).0: i32) = move _12; // scope 6 at $DIR/separate_const_switch.rs:29:8: 29:10 + discriminant(_3) = 0; // scope 6 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_12); // scope 6 at $DIR/separate_const_switch.rs:29:8: 29:10 + StorageDead(_11); // scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 +- goto -> bb1; // scope 5 at $DIR/separate_const_switch.rs:29:8: 29:10 ++ StorageDead(_10); // scope 0 at $DIR/separate_const_switch.rs:29:8: 29:10 ++ StorageDead(_4); // scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 ++ _5 = discriminant(_3); // scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 ++ switchInt(move _5) -> [0_isize: bb1, otherwise: bb2]; // scope 0 at $DIR/separate_const_switch.rs:29:9: 29:10 + } + } + diff --git a/src/test/mir-opt/separate_const_switch.rs b/src/test/mir-opt/separate_const_switch.rs new file mode 100644 index 0000000000000..5d82acf4d6090 --- /dev/null +++ b/src/test/mir-opt/separate_const_switch.rs @@ -0,0 +1,35 @@ +#![feature(control_flow_enum)] +#![feature(try_trait_v2)] + +use std::ops::ControlFlow; + +// EMIT_MIR separate_const_switch.too_complex.SeparateConstSwitch.diff +// EMIT_MIR separate_const_switch.too_complex.ConstProp.diff +// EMIT_MIR separate_const_switch.too_complex.PreCodegen.after.mir +fn too_complex(x: Result) -> Option { + // The pass should break the outer match into + // two blocks that only have one parent each. + // Parents are one of the two branches of the first + // match, so a later pass can propagate constants. + match { + match x { + Ok(v) => ControlFlow::Continue(v), + Err(r) => ControlFlow::Break(r), + } + } { + ControlFlow::Continue(v) => Some(v), + ControlFlow::Break(r) => None, + } +} + +// EMIT_MIR separate_const_switch.identity.SeparateConstSwitch.diff +// EMIT_MIR separate_const_switch.identity.ConstProp.diff +// EMIT_MIR separate_const_switch.identity.PreCodegen.after.mir +fn identity(x: Result) -> Result { + Ok(x?) +} + +fn main() { + too_complex(Ok(0)); + identity(Ok(0)); +} diff --git a/src/test/mir-opt/separate_const_switch.too_complex.ConstProp.diff b/src/test/mir-opt/separate_const_switch.too_complex.ConstProp.diff new file mode 100644 index 0000000000000..973b7838eca35 --- /dev/null +++ b/src/test/mir-opt/separate_const_switch.too_complex.ConstProp.diff @@ -0,0 +1,91 @@ +- // MIR for `too_complex` before ConstProp ++ // MIR for `too_complex` after ConstProp + + fn too_complex(_1: Result) -> Option { + debug x => _1; // in scope 0 at $DIR/separate_const_switch.rs:9:16: 9:17 + let mut _0: std::option::Option; // return place in scope 0 at $DIR/separate_const_switch.rs:9:42: 9:53 + let mut _2: std::ops::ControlFlow; // in scope 0 at $DIR/separate_const_switch.rs:14:11: 19:6 + let mut _3: isize; // in scope 0 at $DIR/separate_const_switch.rs:16:13: 16:18 + let _4: i32; // in scope 0 at $DIR/separate_const_switch.rs:16:16: 16:17 + let mut _5: i32; // in scope 0 at $DIR/separate_const_switch.rs:16:44: 16:45 + let _6: usize; // in scope 0 at $DIR/separate_const_switch.rs:17:17: 17:18 + let mut _7: usize; // in scope 0 at $DIR/separate_const_switch.rs:17:42: 17:43 + let mut _8: isize; // in scope 0 at $DIR/separate_const_switch.rs:20:9: 20:33 + let _9: i32; // in scope 0 at $DIR/separate_const_switch.rs:20:31: 20:32 + let mut _10: i32; // in scope 0 at $DIR/separate_const_switch.rs:20:42: 20:43 + let _11: usize; // in scope 0 at $DIR/separate_const_switch.rs:21:28: 21:29 + scope 1 { + debug v => _4; // in scope 1 at $DIR/separate_const_switch.rs:16:16: 16:17 + } + scope 2 { + debug r => _6; // in scope 2 at $DIR/separate_const_switch.rs:17:17: 17:18 + } + scope 3 { + debug v => _9; // in scope 3 at $DIR/separate_const_switch.rs:20:31: 20:32 + } + scope 4 { + debug r => _11; // in scope 4 at $DIR/separate_const_switch.rs:21:28: 21:29 + } + + bb0: { + StorageLive(_2); // scope 0 at $DIR/separate_const_switch.rs:14:11: 19:6 + _3 = discriminant(_1); // scope 0 at $DIR/separate_const_switch.rs:16:13: 16:18 + switchInt(move _3) -> [0_isize: bb2, otherwise: bb1]; // scope 0 at $DIR/separate_const_switch.rs:16:13: 16:18 + } + + bb1: { + StorageLive(_6); // scope 0 at $DIR/separate_const_switch.rs:17:17: 17:18 + _6 = ((_1 as Err).0: usize); // scope 0 at $DIR/separate_const_switch.rs:17:17: 17:18 + StorageLive(_7); // scope 2 at $DIR/separate_const_switch.rs:17:42: 17:43 + _7 = _6; // scope 2 at $DIR/separate_const_switch.rs:17:42: 17:43 + ((_2 as Break).0: usize) = move _7; // scope 2 at $DIR/separate_const_switch.rs:17:23: 17:44 + discriminant(_2) = 1; // scope 2 at $DIR/separate_const_switch.rs:17:23: 17:44 + StorageDead(_7); // scope 2 at $DIR/separate_const_switch.rs:17:43: 17:44 + StorageDead(_6); // scope 0 at $DIR/separate_const_switch.rs:17:43: 17:44 +- _8 = discriminant(_2); // scope 0 at $DIR/separate_const_switch.rs:20:9: 20:33 +- switchInt(move _8) -> [0_isize: bb4, otherwise: bb3]; // scope 0 at $DIR/separate_const_switch.rs:20:9: 20:33 ++ _8 = const 1_isize; // scope 0 at $DIR/separate_const_switch.rs:20:9: 20:33 ++ switchInt(const 1_isize) -> [0_isize: bb4, otherwise: bb3]; // scope 0 at $DIR/separate_const_switch.rs:20:9: 20:33 + } + + bb2: { + StorageLive(_4); // scope 0 at $DIR/separate_const_switch.rs:16:16: 16:17 + _4 = ((_1 as Ok).0: i32); // scope 0 at $DIR/separate_const_switch.rs:16:16: 16:17 + StorageLive(_5); // scope 1 at $DIR/separate_const_switch.rs:16:44: 16:45 + _5 = _4; // scope 1 at $DIR/separate_const_switch.rs:16:44: 16:45 + ((_2 as Continue).0: i32) = move _5; // scope 1 at $DIR/separate_const_switch.rs:16:22: 16:46 + discriminant(_2) = 0; // scope 1 at $DIR/separate_const_switch.rs:16:22: 16:46 + StorageDead(_5); // scope 1 at $DIR/separate_const_switch.rs:16:45: 16:46 + StorageDead(_4); // scope 0 at $DIR/separate_const_switch.rs:16:45: 16:46 +- _8 = discriminant(_2); // scope 0 at $DIR/separate_const_switch.rs:20:9: 20:33 +- switchInt(move _8) -> [0_isize: bb4, otherwise: bb3]; // scope 0 at $DIR/separate_const_switch.rs:20:9: 20:33 ++ _8 = const 0_isize; // scope 0 at $DIR/separate_const_switch.rs:20:9: 20:33 ++ switchInt(const 0_isize) -> [0_isize: bb4, otherwise: bb3]; // scope 0 at $DIR/separate_const_switch.rs:20:9: 20:33 + } + + bb3: { + StorageLive(_11); // scope 0 at $DIR/separate_const_switch.rs:21:28: 21:29 + _11 = ((_2 as Break).0: usize); // scope 0 at $DIR/separate_const_switch.rs:21:28: 21:29 + discriminant(_0) = 0; // scope 4 at $DIR/separate_const_switch.rs:21:34: 21:38 + StorageDead(_11); // scope 0 at $DIR/separate_const_switch.rs:21:37: 21:38 + goto -> bb5; // scope 0 at $DIR/separate_const_switch.rs:14:5: 22:6 + } + + bb4: { + StorageLive(_9); // scope 0 at $DIR/separate_const_switch.rs:20:31: 20:32 + _9 = ((_2 as Continue).0: i32); // scope 0 at $DIR/separate_const_switch.rs:20:31: 20:32 + StorageLive(_10); // scope 3 at $DIR/separate_const_switch.rs:20:42: 20:43 + _10 = _9; // scope 3 at $DIR/separate_const_switch.rs:20:42: 20:43 + ((_0 as Some).0: i32) = move _10; // scope 3 at $DIR/separate_const_switch.rs:20:37: 20:44 + discriminant(_0) = 1; // scope 3 at $DIR/separate_const_switch.rs:20:37: 20:44 + StorageDead(_10); // scope 3 at $DIR/separate_const_switch.rs:20:43: 20:44 + StorageDead(_9); // scope 0 at $DIR/separate_const_switch.rs:20:43: 20:44 + goto -> bb5; // scope 0 at $DIR/separate_const_switch.rs:14:5: 22:6 + } + + bb5: { + StorageDead(_2); // scope 0 at $DIR/separate_const_switch.rs:23:1: 23:2 + return; // scope 0 at $DIR/separate_const_switch.rs:23:2: 23:2 + } + } + diff --git a/src/test/mir-opt/separate_const_switch.too_complex.PreCodegen.after.mir b/src/test/mir-opt/separate_const_switch.too_complex.PreCodegen.after.mir new file mode 100644 index 0000000000000..cc941f251cea5 --- /dev/null +++ b/src/test/mir-opt/separate_const_switch.too_complex.PreCodegen.after.mir @@ -0,0 +1,74 @@ +// MIR for `too_complex` after PreCodegen + +fn too_complex(_1: Result) -> Option { + debug x => _1; // in scope 0 at $DIR/separate_const_switch.rs:9:16: 9:17 + let mut _0: std::option::Option; // return place in scope 0 at $DIR/separate_const_switch.rs:9:42: 9:53 + let mut _2: std::ops::ControlFlow; // in scope 0 at $DIR/separate_const_switch.rs:14:11: 19:6 + let mut _3: isize; // in scope 0 at $DIR/separate_const_switch.rs:16:13: 16:18 + let _4: i32; // in scope 0 at $DIR/separate_const_switch.rs:16:16: 16:17 + let mut _5: i32; // in scope 0 at $DIR/separate_const_switch.rs:16:44: 16:45 + let _6: usize; // in scope 0 at $DIR/separate_const_switch.rs:17:17: 17:18 + let mut _7: usize; // in scope 0 at $DIR/separate_const_switch.rs:17:42: 17:43 + let _8: i32; // in scope 0 at $DIR/separate_const_switch.rs:20:31: 20:32 + let mut _9: i32; // in scope 0 at $DIR/separate_const_switch.rs:20:42: 20:43 + let _10: usize; // in scope 0 at $DIR/separate_const_switch.rs:21:28: 21:29 + scope 1 { + debug v => _4; // in scope 1 at $DIR/separate_const_switch.rs:16:16: 16:17 + } + scope 2 { + debug r => _6; // in scope 2 at $DIR/separate_const_switch.rs:17:17: 17:18 + } + scope 3 { + debug v => _8; // in scope 3 at $DIR/separate_const_switch.rs:20:31: 20:32 + } + scope 4 { + debug r => _10; // in scope 4 at $DIR/separate_const_switch.rs:21:28: 21:29 + } + + bb0: { + StorageLive(_2); // scope 0 at $DIR/separate_const_switch.rs:14:11: 19:6 + _3 = discriminant(_1); // scope 0 at $DIR/separate_const_switch.rs:16:13: 16:18 + switchInt(move _3) -> [0_isize: bb2, otherwise: bb1]; // scope 0 at $DIR/separate_const_switch.rs:16:13: 16:18 + } + + bb1: { + StorageLive(_6); // scope 0 at $DIR/separate_const_switch.rs:17:17: 17:18 + _6 = ((_1 as Err).0: usize); // scope 0 at $DIR/separate_const_switch.rs:17:17: 17:18 + StorageLive(_7); // scope 2 at $DIR/separate_const_switch.rs:17:42: 17:43 + _7 = _6; // scope 2 at $DIR/separate_const_switch.rs:17:42: 17:43 + ((_2 as Break).0: usize) = move _7; // scope 2 at $DIR/separate_const_switch.rs:17:23: 17:44 + discriminant(_2) = 1; // scope 2 at $DIR/separate_const_switch.rs:17:23: 17:44 + StorageDead(_7); // scope 2 at $DIR/separate_const_switch.rs:17:43: 17:44 + StorageDead(_6); // scope 0 at $DIR/separate_const_switch.rs:17:43: 17:44 + StorageLive(_10); // scope 0 at $DIR/separate_const_switch.rs:21:28: 21:29 + _10 = ((_2 as Break).0: usize); // scope 0 at $DIR/separate_const_switch.rs:21:28: 21:29 + discriminant(_0) = 0; // scope 4 at $DIR/separate_const_switch.rs:21:34: 21:38 + StorageDead(_10); // scope 0 at $DIR/separate_const_switch.rs:21:37: 21:38 + goto -> bb3; // scope 0 at $DIR/separate_const_switch.rs:14:5: 22:6 + } + + bb2: { + StorageLive(_4); // scope 0 at $DIR/separate_const_switch.rs:16:16: 16:17 + _4 = ((_1 as Ok).0: i32); // scope 0 at $DIR/separate_const_switch.rs:16:16: 16:17 + StorageLive(_5); // scope 1 at $DIR/separate_const_switch.rs:16:44: 16:45 + _5 = _4; // scope 1 at $DIR/separate_const_switch.rs:16:44: 16:45 + ((_2 as Continue).0: i32) = move _5; // scope 1 at $DIR/separate_const_switch.rs:16:22: 16:46 + discriminant(_2) = 0; // scope 1 at $DIR/separate_const_switch.rs:16:22: 16:46 + StorageDead(_5); // scope 1 at $DIR/separate_const_switch.rs:16:45: 16:46 + StorageDead(_4); // scope 0 at $DIR/separate_const_switch.rs:16:45: 16:46 + StorageLive(_8); // scope 0 at $DIR/separate_const_switch.rs:20:31: 20:32 + _8 = ((_2 as Continue).0: i32); // scope 0 at $DIR/separate_const_switch.rs:20:31: 20:32 + StorageLive(_9); // scope 3 at $DIR/separate_const_switch.rs:20:42: 20:43 + _9 = _8; // scope 3 at $DIR/separate_const_switch.rs:20:42: 20:43 + ((_0 as Some).0: i32) = move _9; // scope 3 at $DIR/separate_const_switch.rs:20:37: 20:44 + discriminant(_0) = 1; // scope 3 at $DIR/separate_const_switch.rs:20:37: 20:44 + StorageDead(_9); // scope 3 at $DIR/separate_const_switch.rs:20:43: 20:44 + StorageDead(_8); // scope 0 at $DIR/separate_const_switch.rs:20:43: 20:44 + goto -> bb3; // scope 0 at $DIR/separate_const_switch.rs:14:5: 22:6 + } + + bb3: { + StorageDead(_2); // scope 0 at $DIR/separate_const_switch.rs:23:1: 23:2 + return; // scope 0 at $DIR/separate_const_switch.rs:23:2: 23:2 + } +} diff --git a/src/test/mir-opt/separate_const_switch.too_complex.SeparateConstSwitch.diff b/src/test/mir-opt/separate_const_switch.too_complex.SeparateConstSwitch.diff new file mode 100644 index 0000000000000..ce32227ed653b --- /dev/null +++ b/src/test/mir-opt/separate_const_switch.too_complex.SeparateConstSwitch.diff @@ -0,0 +1,98 @@ +- // MIR for `too_complex` before SeparateConstSwitch ++ // MIR for `too_complex` after SeparateConstSwitch + + fn too_complex(_1: Result) -> Option { + debug x => _1; // in scope 0 at $DIR/separate_const_switch.rs:9:16: 9:17 + let mut _0: std::option::Option; // return place in scope 0 at $DIR/separate_const_switch.rs:9:42: 9:53 + let mut _2: std::ops::ControlFlow; // in scope 0 at $DIR/separate_const_switch.rs:14:11: 19:6 + let mut _3: isize; // in scope 0 at $DIR/separate_const_switch.rs:16:13: 16:18 + let _4: i32; // in scope 0 at $DIR/separate_const_switch.rs:16:16: 16:17 + let mut _5: i32; // in scope 0 at $DIR/separate_const_switch.rs:16:44: 16:45 + let _6: usize; // in scope 0 at $DIR/separate_const_switch.rs:17:17: 17:18 + let mut _7: usize; // in scope 0 at $DIR/separate_const_switch.rs:17:42: 17:43 + let mut _8: isize; // in scope 0 at $DIR/separate_const_switch.rs:20:9: 20:33 + let _9: i32; // in scope 0 at $DIR/separate_const_switch.rs:20:31: 20:32 + let mut _10: i32; // in scope 0 at $DIR/separate_const_switch.rs:20:42: 20:43 + let _11: usize; // in scope 0 at $DIR/separate_const_switch.rs:21:28: 21:29 + scope 1 { + debug v => _4; // in scope 1 at $DIR/separate_const_switch.rs:16:16: 16:17 + } + scope 2 { + debug r => _6; // in scope 2 at $DIR/separate_const_switch.rs:17:17: 17:18 + } + scope 3 { + debug v => _9; // in scope 3 at $DIR/separate_const_switch.rs:20:31: 20:32 + } + scope 4 { + debug r => _11; // in scope 4 at $DIR/separate_const_switch.rs:21:28: 21:29 + } + + bb0: { + StorageLive(_2); // scope 0 at $DIR/separate_const_switch.rs:14:11: 19:6 + _3 = discriminant(_1); // scope 0 at $DIR/separate_const_switch.rs:16:13: 16:18 + switchInt(move _3) -> [0_isize: bb2, otherwise: bb1]; // scope 0 at $DIR/separate_const_switch.rs:16:13: 16:18 + } + + bb1: { + StorageLive(_6); // scope 0 at $DIR/separate_const_switch.rs:17:17: 17:18 + _6 = ((_1 as Err).0: usize); // scope 0 at $DIR/separate_const_switch.rs:17:17: 17:18 + StorageLive(_7); // scope 2 at $DIR/separate_const_switch.rs:17:42: 17:43 + _7 = _6; // scope 2 at $DIR/separate_const_switch.rs:17:42: 17:43 + ((_2 as Break).0: usize) = move _7; // scope 2 at $DIR/separate_const_switch.rs:17:23: 17:44 + discriminant(_2) = 1; // scope 2 at $DIR/separate_const_switch.rs:17:23: 17:44 + StorageDead(_7); // scope 2 at $DIR/separate_const_switch.rs:17:43: 17:44 + StorageDead(_6); // scope 0 at $DIR/separate_const_switch.rs:17:43: 17:44 +- goto -> bb3; // scope 0 at $DIR/separate_const_switch.rs:15:9: 18:10 ++ _8 = discriminant(_2); // scope 0 at $DIR/separate_const_switch.rs:20:9: 20:33 ++ switchInt(move _8) -> [0_isize: bb4, otherwise: bb3]; // scope 0 at $DIR/separate_const_switch.rs:20:9: 20:33 + } + + bb2: { + StorageLive(_4); // scope 0 at $DIR/separate_const_switch.rs:16:16: 16:17 + _4 = ((_1 as Ok).0: i32); // scope 0 at $DIR/separate_const_switch.rs:16:16: 16:17 + StorageLive(_5); // scope 1 at $DIR/separate_const_switch.rs:16:44: 16:45 + _5 = _4; // scope 1 at $DIR/separate_const_switch.rs:16:44: 16:45 + ((_2 as Continue).0: i32) = move _5; // scope 1 at $DIR/separate_const_switch.rs:16:22: 16:46 + discriminant(_2) = 0; // scope 1 at $DIR/separate_const_switch.rs:16:22: 16:46 + StorageDead(_5); // scope 1 at $DIR/separate_const_switch.rs:16:45: 16:46 + StorageDead(_4); // scope 0 at $DIR/separate_const_switch.rs:16:45: 16:46 +- goto -> bb3; // scope 0 at $DIR/separate_const_switch.rs:15:9: 18:10 +- } +- +- bb3: { + _8 = discriminant(_2); // scope 0 at $DIR/separate_const_switch.rs:20:9: 20:33 +- switchInt(move _8) -> [0_isize: bb5, otherwise: bb4]; // scope 0 at $DIR/separate_const_switch.rs:20:9: 20:33 ++ switchInt(move _8) -> [0_isize: bb4, otherwise: bb3]; // scope 0 at $DIR/separate_const_switch.rs:20:9: 20:33 + } + +- bb4: { ++ bb3: { + StorageLive(_11); // scope 0 at $DIR/separate_const_switch.rs:21:28: 21:29 + _11 = ((_2 as Break).0: usize); // scope 0 at $DIR/separate_const_switch.rs:21:28: 21:29 + discriminant(_0) = 0; // scope 4 at $DIR/separate_const_switch.rs:21:34: 21:38 + StorageDead(_11); // scope 0 at $DIR/separate_const_switch.rs:21:37: 21:38 +- goto -> bb6; // scope 0 at $DIR/separate_const_switch.rs:14:5: 22:6 ++ goto -> bb5; // scope 0 at $DIR/separate_const_switch.rs:14:5: 22:6 + } + +- bb5: { ++ bb4: { + StorageLive(_9); // scope 0 at $DIR/separate_const_switch.rs:20:31: 20:32 + _9 = ((_2 as Continue).0: i32); // scope 0 at $DIR/separate_const_switch.rs:20:31: 20:32 + StorageLive(_10); // scope 3 at $DIR/separate_const_switch.rs:20:42: 20:43 + _10 = _9; // scope 3 at $DIR/separate_const_switch.rs:20:42: 20:43 + ((_0 as Some).0: i32) = move _10; // scope 3 at $DIR/separate_const_switch.rs:20:37: 20:44 + discriminant(_0) = 1; // scope 3 at $DIR/separate_const_switch.rs:20:37: 20:44 + StorageDead(_10); // scope 3 at $DIR/separate_const_switch.rs:20:43: 20:44 + StorageDead(_9); // scope 0 at $DIR/separate_const_switch.rs:20:43: 20:44 +- goto -> bb6; // scope 0 at $DIR/separate_const_switch.rs:14:5: 22:6 ++ goto -> bb5; // scope 0 at $DIR/separate_const_switch.rs:14:5: 22:6 + } + +- bb6: { ++ bb5: { + StorageDead(_2); // scope 0 at $DIR/separate_const_switch.rs:23:1: 23:2 + return; // scope 0 at $DIR/separate_const_switch.rs:23:2: 23:2 + } + } +