From d6332ae79cf43b9c6ea74478cc5a4333dae685bb Mon Sep 17 00:00:00 2001 From: Nadrieril Date: Wed, 28 Feb 2024 17:46:31 +0100 Subject: [PATCH] Separate the `bool` case from other integers in `TestKind` --- .../rustc_mir_build/src/build/matches/mod.rs | 17 ++-- .../rustc_mir_build/src/build/matches/test.rs | 77 +++++++++---------- ...fg-initial.after-ElaborateDrops.after.diff | 15 ++-- ...fg-initial.after-ElaborateDrops.after.diff | 15 ++-- 4 files changed, 59 insertions(+), 65 deletions(-) diff --git a/compiler/rustc_mir_build/src/build/matches/mod.rs b/compiler/rustc_mir_build/src/build/matches/mod.rs index 641a278c1d3da..e94489b8189de 100644 --- a/compiler/rustc_mir_build/src/build/matches/mod.rs +++ b/compiler/rustc_mir_build/src/build/matches/mod.rs @@ -1091,21 +1091,18 @@ enum TestKind<'tcx> { variants: BitSet, }, - /// Test what value an integer, `bool`, or `char` has. + /// Test what value an integer or `char` has. SwitchInt { - /// The type of the value that we're testing. - switch_ty: Ty<'tcx>, /// The (ordered) set of values that we test for. /// - /// For integers and `char`s we create a branch to each of the values in - /// `options`, as well as an "otherwise" branch for all other values, even - /// in the (rare) case that `options` is exhaustive. - /// - /// For `bool` we always generate two edges, one for `true` and one for - /// `false`. + /// We create a branch to each of the values in `options`, as well as an "otherwise" branch + /// for all other values, even in the (rare) case that `options` is exhaustive. options: FxIndexMap, u128>, }, + /// Test what value a `bool` has. + If, + /// Test for equality with value, possibly after an unsizing coercion to /// `ty`, Eq { @@ -1611,7 +1608,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { // a test like SwitchInt, we may want to add cases based on the candidates that are // available match test.kind { - TestKind::SwitchInt { switch_ty: _, ref mut options } => { + TestKind::SwitchInt { ref mut options } => { for candidate in candidates.iter() { if !self.add_cases_to_switch(&match_place, candidate, options) { break; diff --git a/compiler/rustc_mir_build/src/build/matches/test.rs b/compiler/rustc_mir_build/src/build/matches/test.rs index 1c97de58863bd..7a5a8a1a81aee 100644 --- a/compiler/rustc_mir_build/src/build/matches/test.rs +++ b/compiler/rustc_mir_build/src/build/matches/test.rs @@ -34,12 +34,12 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { TestKind::Switch { adt_def, variants: BitSet::new_empty(adt_def.variants().len()) } } + TestCase::Constant { .. } if match_pair.pattern.ty.is_bool() => TestKind::If, + TestCase::Constant { .. } if is_switch_ty(match_pair.pattern.ty) => { // For integers, we use a `SwitchInt` match, which allows // us to handle more cases. TestKind::SwitchInt { - switch_ty: match_pair.pattern.ty, - // these maps are empty to start; cases are // added below in add_cases_to_switch options: Default::default(), @@ -182,31 +182,26 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { ); } - TestKind::SwitchInt { switch_ty, ref options } => { - let terminator = if *switch_ty.kind() == ty::Bool { - assert!(!options.is_empty() && options.len() <= 2); - let [first_bb, second_bb] = *target_blocks else { - bug!("`TestKind::SwitchInt` on `bool` should have two targets") - }; - let (true_bb, false_bb) = match options[0] { - 1 => (first_bb, second_bb), - 0 => (second_bb, first_bb), - v => span_bug!(test.span, "expected boolean value but got {:?}", v), - }; - TerminatorKind::if_(Operand::Copy(place), true_bb, false_bb) - } else { - // The switch may be inexhaustive so we have a catch all block - debug_assert_eq!(options.len() + 1, target_blocks.len()); - let otherwise_block = *target_blocks.last().unwrap(); - let switch_targets = SwitchTargets::new( - options.values().copied().zip(target_blocks), - otherwise_block, - ); - TerminatorKind::SwitchInt { - discr: Operand::Copy(place), - targets: switch_targets, - } + TestKind::SwitchInt { ref options } => { + // The switch may be inexhaustive so we have a catch-all block + debug_assert_eq!(options.len() + 1, target_blocks.len()); + let otherwise_block = *target_blocks.last().unwrap(); + let switch_targets = SwitchTargets::new( + options.values().copied().zip(target_blocks), + otherwise_block, + ); + let terminator = TerminatorKind::SwitchInt { + discr: Operand::Copy(place), + targets: switch_targets, + }; + self.cfg.terminate(block, self.source_info(match_start_span), terminator); + } + + TestKind::If => { + let [false_bb, true_bb] = *target_blocks else { + bug!("`TestKind::If` should have two targets") }; + let terminator = TerminatorKind::if_(Operand::Copy(place), true_bb, false_bb); self.cfg.terminate(block, self.source_info(match_start_span), terminator); } @@ -585,14 +580,14 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { // // FIXME(#29623) we could use PatKind::Range to rule // things out here, in some cases. - (TestKind::SwitchInt { switch_ty: _, options }, TestCase::Constant { value }) + (TestKind::SwitchInt { options }, TestCase::Constant { value }) if is_switch_ty(match_pair.pattern.ty) => { fully_matched = true; let index = options.get_index_of(value).unwrap(); Some(index) } - (TestKind::SwitchInt { switch_ty: _, options }, TestCase::Range(range)) => { + (TestKind::SwitchInt { options }, TestCase::Range(range)) => { fully_matched = false; let not_contained = self.values_not_contained_in_range(&*range, options).unwrap_or(false); @@ -608,6 +603,18 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { None } + (&TestKind::If, TestCase::Constant { value }) => { + fully_matched = true; + let value = value.try_eval_bool(self.tcx, self.param_env).unwrap_or_else(|| { + span_bug!(test.span, "expected boolean value but got {value:?}") + }); + Some(value as usize) + } + (&TestKind::If, _) => { + fully_matched = false; + None + } + ( &TestKind::Len { len: test_len, op: BinOp::Eq }, &TestCase::Slice { len, variable_length }, @@ -755,7 +762,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { impl Test<'_> { pub(super) fn targets(&self) -> usize { match self.kind { - TestKind::Eq { .. } | TestKind::Range(_) | TestKind::Len { .. } => 2, + TestKind::Eq { .. } | TestKind::Range(_) | TestKind::Len { .. } | TestKind::If => 2, TestKind::Switch { adt_def, .. } => { // While the switch that we generate doesn't test for all // variants, we have a target for each variant and the @@ -763,21 +770,13 @@ impl Test<'_> { // specified have the same block. adt_def.variants().len() + 1 } - TestKind::SwitchInt { switch_ty, ref options, .. } => { - if switch_ty.is_bool() { - // `bool` is special cased in `perform_test` to always - // branch to two blocks. - 2 - } else { - options.len() + 1 - } - } + TestKind::SwitchInt { ref options } => options.len() + 1, } } } fn is_switch_ty(ty: Ty<'_>) -> bool { - ty.is_integral() || ty.is_char() || ty.is_bool() + ty.is_integral() || ty.is_char() } fn trait_method<'tcx>( diff --git a/tests/mir-opt/match_arm_scopes.complicated_match.panic-abort.SimplifyCfg-initial.after-ElaborateDrops.after.diff b/tests/mir-opt/match_arm_scopes.complicated_match.panic-abort.SimplifyCfg-initial.after-ElaborateDrops.after.diff index 307f7105dd2f1..619fda339a6a9 100644 --- a/tests/mir-opt/match_arm_scopes.complicated_match.panic-abort.SimplifyCfg-initial.after-ElaborateDrops.after.diff +++ b/tests/mir-opt/match_arm_scopes.complicated_match.panic-abort.SimplifyCfg-initial.after-ElaborateDrops.after.diff @@ -42,15 +42,11 @@ } bb2: { -- switchInt((_2.0: bool)) -> [0: bb4, otherwise: bb3]; +- switchInt((_2.0: bool)) -> [0: bb3, otherwise: bb4]; + switchInt((_2.0: bool)) -> [0: bb3, otherwise: bb17]; } bb3: { -- falseEdge -> [real: bb20, imaginary: bb4]; -- } -- -- bb4: { StorageLive(_15); _15 = (_2.1: bool); StorageLive(_16); @@ -59,8 +55,12 @@ + goto -> bb16; } + bb4: { +- falseEdge -> [real: bb20, imaginary: bb3]; +- } +- - bb5: { -- falseEdge -> [real: bb13, imaginary: bb3]; +- falseEdge -> [real: bb13, imaginary: bb4]; - } - - bb6: { @@ -68,7 +68,6 @@ - } - - bb7: { -+ bb4: { _0 = const 1_i32; - drop(_7) -> [return: bb18, unwind: bb25]; + drop(_7) -> [return: bb15, unwind: bb22]; @@ -184,7 +183,7 @@ StorageDead(_12); StorageDead(_8); StorageDead(_6); -- falseEdge -> [real: bb2, imaginary: bb3]; +- falseEdge -> [real: bb2, imaginary: bb4]; + goto -> bb2; } diff --git a/tests/mir-opt/match_arm_scopes.complicated_match.panic-unwind.SimplifyCfg-initial.after-ElaborateDrops.after.diff b/tests/mir-opt/match_arm_scopes.complicated_match.panic-unwind.SimplifyCfg-initial.after-ElaborateDrops.after.diff index 307f7105dd2f1..619fda339a6a9 100644 --- a/tests/mir-opt/match_arm_scopes.complicated_match.panic-unwind.SimplifyCfg-initial.after-ElaborateDrops.after.diff +++ b/tests/mir-opt/match_arm_scopes.complicated_match.panic-unwind.SimplifyCfg-initial.after-ElaborateDrops.after.diff @@ -42,15 +42,11 @@ } bb2: { -- switchInt((_2.0: bool)) -> [0: bb4, otherwise: bb3]; +- switchInt((_2.0: bool)) -> [0: bb3, otherwise: bb4]; + switchInt((_2.0: bool)) -> [0: bb3, otherwise: bb17]; } bb3: { -- falseEdge -> [real: bb20, imaginary: bb4]; -- } -- -- bb4: { StorageLive(_15); _15 = (_2.1: bool); StorageLive(_16); @@ -59,8 +55,12 @@ + goto -> bb16; } + bb4: { +- falseEdge -> [real: bb20, imaginary: bb3]; +- } +- - bb5: { -- falseEdge -> [real: bb13, imaginary: bb3]; +- falseEdge -> [real: bb13, imaginary: bb4]; - } - - bb6: { @@ -68,7 +68,6 @@ - } - - bb7: { -+ bb4: { _0 = const 1_i32; - drop(_7) -> [return: bb18, unwind: bb25]; + drop(_7) -> [return: bb15, unwind: bb22]; @@ -184,7 +183,7 @@ StorageDead(_12); StorageDead(_8); StorageDead(_6); -- falseEdge -> [real: bb2, imaginary: bb3]; +- falseEdge -> [real: bb2, imaginary: bb4]; + goto -> bb2; }