mirror of https://github.com/rust-lang/rust.git
Auto merge of #120614 - DianQK:simplify-switch-int, r=cjgillot
Transforms match into an assignment statement Fixes #106459. We should be able to do some similar transformations, like `enum` to `enum`. r? mir-opt
This commit is contained in:
commit
211518e5fb
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@ -85,6 +85,12 @@ impl SwitchTargets {
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self.values.push(value);
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self.values.push(value);
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self.targets.insert(self.targets.len() - 1, bb);
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self.targets.insert(self.targets.len() - 1, bb);
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}
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}
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/// Returns true if all targets (including the fallback target) are distinct.
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#[inline]
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pub fn is_distinct(&self) -> bool {
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self.targets.iter().collect::<FxHashSet<_>>().len() == self.targets.len()
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}
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}
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}
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pub struct SwitchTargetsIter<'a> {
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pub struct SwitchTargetsIter<'a> {
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@ -1,11 +1,125 @@
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use rustc_index::IndexSlice;
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use rustc_middle::mir::patch::MirPatch;
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use rustc_middle::mir::*;
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use rustc_middle::mir::*;
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use rustc_middle::ty::TyCtxt;
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use rustc_middle::ty::{ParamEnv, ScalarInt, Ty, TyCtxt};
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use rustc_target::abi::Size;
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use std::iter;
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use std::iter;
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use super::simplify::simplify_cfg;
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use super::simplify::simplify_cfg;
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pub struct MatchBranchSimplification;
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pub struct MatchBranchSimplification;
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impl<'tcx> MirPass<'tcx> for MatchBranchSimplification {
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fn is_enabled(&self, sess: &rustc_session::Session) -> bool {
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sess.mir_opt_level() >= 1
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}
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fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
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let def_id = body.source.def_id();
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let param_env = tcx.param_env_reveal_all_normalized(def_id);
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let mut should_cleanup = false;
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for i in 0..body.basic_blocks.len() {
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let bbs = &*body.basic_blocks;
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let bb_idx = BasicBlock::from_usize(i);
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if !tcx.consider_optimizing(|| format!("MatchBranchSimplification {def_id:?} ")) {
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continue;
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}
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match bbs[bb_idx].terminator().kind {
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TerminatorKind::SwitchInt {
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discr: ref _discr @ (Operand::Copy(_) | Operand::Move(_)),
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ref targets,
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..
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// We require that the possible target blocks don't contain this block.
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} if !targets.all_targets().contains(&bb_idx) => {}
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// Only optimize switch int statements
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_ => continue,
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};
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if SimplifyToIf.simplify(tcx, body, bb_idx, param_env).is_some() {
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should_cleanup = true;
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continue;
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}
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if SimplifyToExp::default().simplify(tcx, body, bb_idx, param_env).is_some() {
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should_cleanup = true;
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continue;
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}
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}
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if should_cleanup {
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simplify_cfg(body);
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}
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}
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}
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trait SimplifyMatch<'tcx> {
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/// Simplifies a match statement, returning true if the simplification succeeds, false otherwise.
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/// Generic code is written here, and we generally don't need a custom implementation.
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fn simplify(
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&mut self,
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tcx: TyCtxt<'tcx>,
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body: &mut Body<'tcx>,
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switch_bb_idx: BasicBlock,
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param_env: ParamEnv<'tcx>,
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) -> Option<()> {
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let bbs = &body.basic_blocks;
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let (discr, targets) = match bbs[switch_bb_idx].terminator().kind {
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TerminatorKind::SwitchInt { ref discr, ref targets, .. } => (discr, targets),
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_ => unreachable!(),
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};
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let discr_ty = discr.ty(body.local_decls(), tcx);
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self.can_simplify(tcx, targets, param_env, bbs, discr_ty)?;
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let mut patch = MirPatch::new(body);
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// Take ownership of items now that we know we can optimize.
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let discr = discr.clone();
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// Introduce a temporary for the discriminant value.
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let source_info = bbs[switch_bb_idx].terminator().source_info;
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let discr_local = patch.new_temp(discr_ty, source_info.span);
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let (_, first) = targets.iter().next().unwrap();
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let statement_index = bbs[switch_bb_idx].statements.len();
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let parent_end = Location { block: switch_bb_idx, statement_index };
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patch.add_statement(parent_end, StatementKind::StorageLive(discr_local));
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patch.add_assign(parent_end, Place::from(discr_local), Rvalue::Use(discr));
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self.new_stmts(tcx, targets, param_env, &mut patch, parent_end, bbs, discr_local, discr_ty);
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patch.add_statement(parent_end, StatementKind::StorageDead(discr_local));
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patch.patch_terminator(switch_bb_idx, bbs[first].terminator().kind.clone());
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patch.apply(body);
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Some(())
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}
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/// Check that the BBs to be simplified satisfies all distinct and
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/// that the terminator are the same.
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/// There are also conditions for different ways of simplification.
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fn can_simplify(
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&mut self,
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tcx: TyCtxt<'tcx>,
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targets: &SwitchTargets,
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param_env: ParamEnv<'tcx>,
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bbs: &IndexSlice<BasicBlock, BasicBlockData<'tcx>>,
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discr_ty: Ty<'tcx>,
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) -> Option<()>;
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fn new_stmts(
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&self,
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tcx: TyCtxt<'tcx>,
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targets: &SwitchTargets,
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param_env: ParamEnv<'tcx>,
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patch: &mut MirPatch<'tcx>,
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parent_end: Location,
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bbs: &IndexSlice<BasicBlock, BasicBlockData<'tcx>>,
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discr_local: Local,
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discr_ty: Ty<'tcx>,
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);
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}
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struct SimplifyToIf;
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/// If a source block is found that switches between two blocks that are exactly
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/// If a source block is found that switches between two blocks that are exactly
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/// the same modulo const bool assignments (e.g., one assigns true another false
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/// the same modulo const bool assignments (e.g., one assigns true another false
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/// to the same place), merge a target block statements into the source block,
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/// to the same place), merge a target block statements into the source block,
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@ -37,144 +151,350 @@ pub struct MatchBranchSimplification;
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/// goto -> bb3;
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/// goto -> bb3;
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/// }
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/// }
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/// ```
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/// ```
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impl<'tcx> SimplifyMatch<'tcx> for SimplifyToIf {
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impl<'tcx> MirPass<'tcx> for MatchBranchSimplification {
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fn can_simplify(
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fn is_enabled(&self, sess: &rustc_session::Session) -> bool {
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&mut self,
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sess.mir_opt_level() >= 1
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tcx: TyCtxt<'tcx>,
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}
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targets: &SwitchTargets,
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param_env: ParamEnv<'tcx>,
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fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
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bbs: &IndexSlice<BasicBlock, BasicBlockData<'tcx>>,
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let def_id = body.source.def_id();
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_discr_ty: Ty<'tcx>,
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let param_env = tcx.param_env_reveal_all_normalized(def_id);
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) -> Option<()> {
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if targets.iter().len() != 1 {
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let bbs = body.basic_blocks.as_mut();
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return None;
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let mut should_cleanup = false;
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}
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'outer: for bb_idx in bbs.indices() {
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// We require that the possible target blocks all be distinct.
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if !tcx.consider_optimizing(|| format!("MatchBranchSimplification {def_id:?} ")) {
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let (_, first) = targets.iter().next().unwrap();
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continue;
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let second = targets.otherwise();
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}
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if first == second {
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return None;
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let (discr, val, first, second) = match bbs[bb_idx].terminator().kind {
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}
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TerminatorKind::SwitchInt {
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// Check that destinations are identical, and if not, then don't optimize this block
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discr: ref discr @ (Operand::Copy(_) | Operand::Move(_)),
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if bbs[first].terminator().kind != bbs[second].terminator().kind {
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ref targets,
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return None;
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..
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} if targets.iter().len() == 1 => {
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let (value, target) = targets.iter().next().unwrap();
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// We require that this block and the two possible target blocks all be
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// distinct.
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if target == targets.otherwise()
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|| bb_idx == target
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|| bb_idx == targets.otherwise()
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{
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continue;
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}
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(discr, value, target, targets.otherwise())
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}
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// Only optimize switch int statements
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_ => continue,
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};
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// Check that destinations are identical, and if not, then don't optimize this block
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if bbs[first].terminator().kind != bbs[second].terminator().kind {
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continue;
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}
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// Check that blocks are assignments of consts to the same place or same statement,
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// and match up 1-1, if not don't optimize this block.
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let first_stmts = &bbs[first].statements;
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let scnd_stmts = &bbs[second].statements;
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if first_stmts.len() != scnd_stmts.len() {
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continue;
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}
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for (f, s) in iter::zip(first_stmts, scnd_stmts) {
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match (&f.kind, &s.kind) {
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// If two statements are exactly the same, we can optimize.
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(f_s, s_s) if f_s == s_s => {}
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// If two statements are const bool assignments to the same place, we can optimize.
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(
|
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StatementKind::Assign(box (lhs_f, Rvalue::Use(Operand::Constant(f_c)))),
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StatementKind::Assign(box (lhs_s, Rvalue::Use(Operand::Constant(s_c)))),
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) if lhs_f == lhs_s
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&& f_c.const_.ty().is_bool()
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&& s_c.const_.ty().is_bool()
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&& f_c.const_.try_eval_bool(tcx, param_env).is_some()
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&& s_c.const_.try_eval_bool(tcx, param_env).is_some() => {}
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// Otherwise we cannot optimize. Try another block.
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_ => continue 'outer,
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}
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}
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// Take ownership of items now that we know we can optimize.
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let discr = discr.clone();
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let discr_ty = discr.ty(&body.local_decls, tcx);
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// Introduce a temporary for the discriminant value.
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let source_info = bbs[bb_idx].terminator().source_info;
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let discr_local = body.local_decls.push(LocalDecl::new(discr_ty, source_info.span));
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// We already checked that first and second are different blocks,
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// and bb_idx has a different terminator from both of them.
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let (from, first, second) = bbs.pick3_mut(bb_idx, first, second);
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let new_stmts = iter::zip(&first.statements, &second.statements).map(|(f, s)| {
|
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match (&f.kind, &s.kind) {
|
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(f_s, s_s) if f_s == s_s => (*f).clone(),
|
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||||||
|
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(
|
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StatementKind::Assign(box (lhs, Rvalue::Use(Operand::Constant(f_c)))),
|
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StatementKind::Assign(box (_, Rvalue::Use(Operand::Constant(s_c)))),
|
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) => {
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// From earlier loop we know that we are dealing with bool constants only:
|
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let f_b = f_c.const_.try_eval_bool(tcx, param_env).unwrap();
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let s_b = s_c.const_.try_eval_bool(tcx, param_env).unwrap();
|
|
||||||
if f_b == s_b {
|
|
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// Same value in both blocks. Use statement as is.
|
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(*f).clone()
|
|
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} else {
|
|
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// Different value between blocks. Make value conditional on switch condition.
|
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let size = tcx.layout_of(param_env.and(discr_ty)).unwrap().size;
|
|
||||||
let const_cmp = Operand::const_from_scalar(
|
|
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tcx,
|
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discr_ty,
|
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rustc_const_eval::interpret::Scalar::from_uint(val, size),
|
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rustc_span::DUMMY_SP,
|
|
||||||
);
|
|
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let op = if f_b { BinOp::Eq } else { BinOp::Ne };
|
|
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let rhs = Rvalue::BinaryOp(
|
|
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op,
|
|
||||||
Box::new((Operand::Copy(Place::from(discr_local)), const_cmp)),
|
|
||||||
);
|
|
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Statement {
|
|
||||||
source_info: f.source_info,
|
|
||||||
kind: StatementKind::Assign(Box::new((*lhs, rhs))),
|
|
||||||
}
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
_ => unreachable!(),
|
|
||||||
}
|
|
||||||
});
|
|
||||||
|
|
||||||
from.statements
|
|
||||||
.push(Statement { source_info, kind: StatementKind::StorageLive(discr_local) });
|
|
||||||
from.statements.push(Statement {
|
|
||||||
source_info,
|
|
||||||
kind: StatementKind::Assign(Box::new((
|
|
||||||
Place::from(discr_local),
|
|
||||||
Rvalue::Use(discr),
|
|
||||||
))),
|
|
||||||
});
|
|
||||||
from.statements.extend(new_stmts);
|
|
||||||
from.statements
|
|
||||||
.push(Statement { source_info, kind: StatementKind::StorageDead(discr_local) });
|
|
||||||
from.terminator_mut().kind = first.terminator().kind.clone();
|
|
||||||
should_cleanup = true;
|
|
||||||
}
|
}
|
||||||
|
|
||||||
if should_cleanup {
|
// Check that blocks are assignments of consts to the same place or same statement,
|
||||||
simplify_cfg(body);
|
// and match up 1-1, if not don't optimize this block.
|
||||||
|
let first_stmts = &bbs[first].statements;
|
||||||
|
let second_stmts = &bbs[second].statements;
|
||||||
|
if first_stmts.len() != second_stmts.len() {
|
||||||
|
return None;
|
||||||
|
}
|
||||||
|
for (f, s) in iter::zip(first_stmts, second_stmts) {
|
||||||
|
match (&f.kind, &s.kind) {
|
||||||
|
// If two statements are exactly the same, we can optimize.
|
||||||
|
(f_s, s_s) if f_s == s_s => {}
|
||||||
|
|
||||||
|
// If two statements are const bool assignments to the same place, we can optimize.
|
||||||
|
(
|
||||||
|
StatementKind::Assign(box (lhs_f, Rvalue::Use(Operand::Constant(f_c)))),
|
||||||
|
StatementKind::Assign(box (lhs_s, Rvalue::Use(Operand::Constant(s_c)))),
|
||||||
|
) if lhs_f == lhs_s
|
||||||
|
&& f_c.const_.ty().is_bool()
|
||||||
|
&& s_c.const_.ty().is_bool()
|
||||||
|
&& f_c.const_.try_eval_bool(tcx, param_env).is_some()
|
||||||
|
&& s_c.const_.try_eval_bool(tcx, param_env).is_some() => {}
|
||||||
|
|
||||||
|
// Otherwise we cannot optimize. Try another block.
|
||||||
|
_ => return None,
|
||||||
|
}
|
||||||
|
}
|
||||||
|
Some(())
|
||||||
|
}
|
||||||
|
|
||||||
|
fn new_stmts(
|
||||||
|
&self,
|
||||||
|
tcx: TyCtxt<'tcx>,
|
||||||
|
targets: &SwitchTargets,
|
||||||
|
param_env: ParamEnv<'tcx>,
|
||||||
|
patch: &mut MirPatch<'tcx>,
|
||||||
|
parent_end: Location,
|
||||||
|
bbs: &IndexSlice<BasicBlock, BasicBlockData<'tcx>>,
|
||||||
|
discr_local: Local,
|
||||||
|
discr_ty: Ty<'tcx>,
|
||||||
|
) {
|
||||||
|
let (val, first) = targets.iter().next().unwrap();
|
||||||
|
let second = targets.otherwise();
|
||||||
|
// We already checked that first and second are different blocks,
|
||||||
|
// and bb_idx has a different terminator from both of them.
|
||||||
|
let first = &bbs[first];
|
||||||
|
let second = &bbs[second];
|
||||||
|
for (f, s) in iter::zip(&first.statements, &second.statements) {
|
||||||
|
match (&f.kind, &s.kind) {
|
||||||
|
(f_s, s_s) if f_s == s_s => {
|
||||||
|
patch.add_statement(parent_end, f.kind.clone());
|
||||||
|
}
|
||||||
|
|
||||||
|
(
|
||||||
|
StatementKind::Assign(box (lhs, Rvalue::Use(Operand::Constant(f_c)))),
|
||||||
|
StatementKind::Assign(box (_, Rvalue::Use(Operand::Constant(s_c)))),
|
||||||
|
) => {
|
||||||
|
// From earlier loop we know that we are dealing with bool constants only:
|
||||||
|
let f_b = f_c.const_.try_eval_bool(tcx, param_env).unwrap();
|
||||||
|
let s_b = s_c.const_.try_eval_bool(tcx, param_env).unwrap();
|
||||||
|
if f_b == s_b {
|
||||||
|
// Same value in both blocks. Use statement as is.
|
||||||
|
patch.add_statement(parent_end, f.kind.clone());
|
||||||
|
} else {
|
||||||
|
// Different value between blocks. Make value conditional on switch condition.
|
||||||
|
let size = tcx.layout_of(param_env.and(discr_ty)).unwrap().size;
|
||||||
|
let const_cmp = Operand::const_from_scalar(
|
||||||
|
tcx,
|
||||||
|
discr_ty,
|
||||||
|
rustc_const_eval::interpret::Scalar::from_uint(val, size),
|
||||||
|
rustc_span::DUMMY_SP,
|
||||||
|
);
|
||||||
|
let op = if f_b { BinOp::Eq } else { BinOp::Ne };
|
||||||
|
let rhs = Rvalue::BinaryOp(
|
||||||
|
op,
|
||||||
|
Box::new((Operand::Copy(Place::from(discr_local)), const_cmp)),
|
||||||
|
);
|
||||||
|
patch.add_assign(parent_end, *lhs, rhs);
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
_ => unreachable!(),
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
#[derive(Default)]
|
||||||
|
struct SimplifyToExp {
|
||||||
|
transfrom_types: Vec<TransfromType>,
|
||||||
|
}
|
||||||
|
|
||||||
|
#[derive(Clone, Copy)]
|
||||||
|
enum CompareType<'tcx, 'a> {
|
||||||
|
/// Identical statements.
|
||||||
|
Same(&'a StatementKind<'tcx>),
|
||||||
|
/// Assignment statements have the same value.
|
||||||
|
Eq(&'a Place<'tcx>, Ty<'tcx>, ScalarInt),
|
||||||
|
/// Enum variant comparison type.
|
||||||
|
Discr { place: &'a Place<'tcx>, ty: Ty<'tcx>, is_signed: bool },
|
||||||
|
}
|
||||||
|
|
||||||
|
enum TransfromType {
|
||||||
|
Same,
|
||||||
|
Eq,
|
||||||
|
Discr,
|
||||||
|
}
|
||||||
|
|
||||||
|
impl From<CompareType<'_, '_>> for TransfromType {
|
||||||
|
fn from(compare_type: CompareType<'_, '_>) -> Self {
|
||||||
|
match compare_type {
|
||||||
|
CompareType::Same(_) => TransfromType::Same,
|
||||||
|
CompareType::Eq(_, _, _) => TransfromType::Eq,
|
||||||
|
CompareType::Discr { .. } => TransfromType::Discr,
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
/// If we find that the value of match is the same as the assignment,
|
||||||
|
/// merge a target block statements into the source block,
|
||||||
|
/// using cast to transform different integer types.
|
||||||
|
///
|
||||||
|
/// For example:
|
||||||
|
///
|
||||||
|
/// ```ignore (MIR)
|
||||||
|
/// bb0: {
|
||||||
|
/// switchInt(_1) -> [1: bb2, 2: bb3, 3: bb4, otherwise: bb1];
|
||||||
|
/// }
|
||||||
|
///
|
||||||
|
/// bb1: {
|
||||||
|
/// unreachable;
|
||||||
|
/// }
|
||||||
|
///
|
||||||
|
/// bb2: {
|
||||||
|
/// _0 = const 1_i16;
|
||||||
|
/// goto -> bb5;
|
||||||
|
/// }
|
||||||
|
///
|
||||||
|
/// bb3: {
|
||||||
|
/// _0 = const 2_i16;
|
||||||
|
/// goto -> bb5;
|
||||||
|
/// }
|
||||||
|
///
|
||||||
|
/// bb4: {
|
||||||
|
/// _0 = const 3_i16;
|
||||||
|
/// goto -> bb5;
|
||||||
|
/// }
|
||||||
|
/// ```
|
||||||
|
///
|
||||||
|
/// into:
|
||||||
|
///
|
||||||
|
/// ```ignore (MIR)
|
||||||
|
/// bb0: {
|
||||||
|
/// _0 = _3 as i16 (IntToInt);
|
||||||
|
/// goto -> bb5;
|
||||||
|
/// }
|
||||||
|
/// ```
|
||||||
|
impl<'tcx> SimplifyMatch<'tcx> for SimplifyToExp {
|
||||||
|
fn can_simplify(
|
||||||
|
&mut self,
|
||||||
|
tcx: TyCtxt<'tcx>,
|
||||||
|
targets: &SwitchTargets,
|
||||||
|
param_env: ParamEnv<'tcx>,
|
||||||
|
bbs: &IndexSlice<BasicBlock, BasicBlockData<'tcx>>,
|
||||||
|
discr_ty: Ty<'tcx>,
|
||||||
|
) -> Option<()> {
|
||||||
|
if targets.iter().len() < 2 || targets.iter().len() > 64 {
|
||||||
|
return None;
|
||||||
|
}
|
||||||
|
// We require that the possible target blocks all be distinct.
|
||||||
|
if !targets.is_distinct() {
|
||||||
|
return None;
|
||||||
|
}
|
||||||
|
if !bbs[targets.otherwise()].is_empty_unreachable() {
|
||||||
|
return None;
|
||||||
|
}
|
||||||
|
let mut target_iter = targets.iter();
|
||||||
|
let (first_val, first_target) = target_iter.next().unwrap();
|
||||||
|
let first_terminator_kind = &bbs[first_target].terminator().kind;
|
||||||
|
// Check that destinations are identical, and if not, then don't optimize this block
|
||||||
|
if !targets
|
||||||
|
.iter()
|
||||||
|
.all(|(_, other_target)| first_terminator_kind == &bbs[other_target].terminator().kind)
|
||||||
|
{
|
||||||
|
return None;
|
||||||
|
}
|
||||||
|
|
||||||
|
let discr_size = tcx.layout_of(param_env.and(discr_ty)).unwrap().size;
|
||||||
|
let first_stmts = &bbs[first_target].statements;
|
||||||
|
let (second_val, second_target) = target_iter.next().unwrap();
|
||||||
|
let second_stmts = &bbs[second_target].statements;
|
||||||
|
if first_stmts.len() != second_stmts.len() {
|
||||||
|
return None;
|
||||||
|
}
|
||||||
|
|
||||||
|
fn int_equal(l: ScalarInt, r: impl Into<u128>, size: Size) -> bool {
|
||||||
|
l.try_to_int(l.size()).unwrap()
|
||||||
|
== ScalarInt::try_from_uint(r, size).unwrap().try_to_int(size).unwrap()
|
||||||
|
}
|
||||||
|
|
||||||
|
// We first compare the two branches, and then the other branches need to fulfill the same conditions.
|
||||||
|
let mut compare_types = Vec::new();
|
||||||
|
for (f, s) in iter::zip(first_stmts, second_stmts) {
|
||||||
|
let compare_type = match (&f.kind, &s.kind) {
|
||||||
|
// If two statements are exactly the same, we can optimize.
|
||||||
|
(f_s, s_s) if f_s == s_s => CompareType::Same(f_s),
|
||||||
|
|
||||||
|
// If two statements are assignments with the match values to the same place, we can optimize.
|
||||||
|
(
|
||||||
|
StatementKind::Assign(box (lhs_f, Rvalue::Use(Operand::Constant(f_c)))),
|
||||||
|
StatementKind::Assign(box (lhs_s, Rvalue::Use(Operand::Constant(s_c)))),
|
||||||
|
) if lhs_f == lhs_s
|
||||||
|
&& f_c.const_.ty() == s_c.const_.ty()
|
||||||
|
&& f_c.const_.ty().is_integral() =>
|
||||||
|
{
|
||||||
|
match (
|
||||||
|
f_c.const_.try_eval_scalar_int(tcx, param_env),
|
||||||
|
s_c.const_.try_eval_scalar_int(tcx, param_env),
|
||||||
|
) {
|
||||||
|
(Some(f), Some(s)) if f == s => CompareType::Eq(lhs_f, f_c.const_.ty(), f),
|
||||||
|
// Enum variants can also be simplified to an assignment statement if their values are equal.
|
||||||
|
// We need to consider both unsigned and signed scenarios here.
|
||||||
|
(Some(f), Some(s))
|
||||||
|
if ((f_c.const_.ty().is_signed() || discr_ty.is_signed())
|
||||||
|
&& int_equal(f, first_val, discr_size)
|
||||||
|
&& int_equal(s, second_val, discr_size))
|
||||||
|
|| (Some(f) == ScalarInt::try_from_uint(first_val, f.size())
|
||||||
|
&& Some(s)
|
||||||
|
== ScalarInt::try_from_uint(second_val, s.size())) =>
|
||||||
|
{
|
||||||
|
CompareType::Discr {
|
||||||
|
place: lhs_f,
|
||||||
|
ty: f_c.const_.ty(),
|
||||||
|
is_signed: f_c.const_.ty().is_signed() || discr_ty.is_signed(),
|
||||||
|
}
|
||||||
|
}
|
||||||
|
_ => {
|
||||||
|
return None;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
// Otherwise we cannot optimize. Try another block.
|
||||||
|
_ => return None,
|
||||||
|
};
|
||||||
|
compare_types.push(compare_type);
|
||||||
|
}
|
||||||
|
|
||||||
|
// All remaining BBs need to fulfill the same pattern as the two BBs from the previous step.
|
||||||
|
for (other_val, other_target) in target_iter {
|
||||||
|
let other_stmts = &bbs[other_target].statements;
|
||||||
|
if compare_types.len() != other_stmts.len() {
|
||||||
|
return None;
|
||||||
|
}
|
||||||
|
for (f, s) in iter::zip(&compare_types, other_stmts) {
|
||||||
|
match (*f, &s.kind) {
|
||||||
|
(CompareType::Same(f_s), s_s) if f_s == s_s => {}
|
||||||
|
(
|
||||||
|
CompareType::Eq(lhs_f, f_ty, val),
|
||||||
|
StatementKind::Assign(box (lhs_s, Rvalue::Use(Operand::Constant(s_c)))),
|
||||||
|
) if lhs_f == lhs_s
|
||||||
|
&& s_c.const_.ty() == f_ty
|
||||||
|
&& s_c.const_.try_eval_scalar_int(tcx, param_env) == Some(val) => {}
|
||||||
|
(
|
||||||
|
CompareType::Discr { place: lhs_f, ty: f_ty, is_signed },
|
||||||
|
StatementKind::Assign(box (lhs_s, Rvalue::Use(Operand::Constant(s_c)))),
|
||||||
|
) if lhs_f == lhs_s && s_c.const_.ty() == f_ty => {
|
||||||
|
let Some(f) = s_c.const_.try_eval_scalar_int(tcx, param_env) else {
|
||||||
|
return None;
|
||||||
|
};
|
||||||
|
if is_signed
|
||||||
|
&& s_c.const_.ty().is_signed()
|
||||||
|
&& int_equal(f, other_val, discr_size)
|
||||||
|
{
|
||||||
|
continue;
|
||||||
|
}
|
||||||
|
if Some(f) == ScalarInt::try_from_uint(other_val, f.size()) {
|
||||||
|
continue;
|
||||||
|
}
|
||||||
|
return None;
|
||||||
|
}
|
||||||
|
_ => return None,
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
self.transfrom_types = compare_types.into_iter().map(|c| c.into()).collect();
|
||||||
|
Some(())
|
||||||
|
}
|
||||||
|
|
||||||
|
fn new_stmts(
|
||||||
|
&self,
|
||||||
|
_tcx: TyCtxt<'tcx>,
|
||||||
|
targets: &SwitchTargets,
|
||||||
|
_param_env: ParamEnv<'tcx>,
|
||||||
|
patch: &mut MirPatch<'tcx>,
|
||||||
|
parent_end: Location,
|
||||||
|
bbs: &IndexSlice<BasicBlock, BasicBlockData<'tcx>>,
|
||||||
|
discr_local: Local,
|
||||||
|
discr_ty: Ty<'tcx>,
|
||||||
|
) {
|
||||||
|
let (_, first) = targets.iter().next().unwrap();
|
||||||
|
let first = &bbs[first];
|
||||||
|
|
||||||
|
for (t, s) in iter::zip(&self.transfrom_types, &first.statements) {
|
||||||
|
match (t, &s.kind) {
|
||||||
|
(TransfromType::Same, _) | (TransfromType::Eq, _) => {
|
||||||
|
patch.add_statement(parent_end, s.kind.clone());
|
||||||
|
}
|
||||||
|
(
|
||||||
|
TransfromType::Discr,
|
||||||
|
StatementKind::Assign(box (lhs, Rvalue::Use(Operand::Constant(f_c)))),
|
||||||
|
) => {
|
||||||
|
let operand = Operand::Copy(Place::from(discr_local));
|
||||||
|
let r_val = if f_c.const_.ty() == discr_ty {
|
||||||
|
Rvalue::Use(operand)
|
||||||
|
} else {
|
||||||
|
Rvalue::Cast(CastKind::IntToInt, operand, f_c.const_.ty())
|
||||||
|
};
|
||||||
|
patch.add_assign(parent_end, *lhs, r_val);
|
||||||
|
}
|
||||||
|
_ => unreachable!(),
|
||||||
|
}
|
||||||
}
|
}
|
||||||
}
|
}
|
||||||
}
|
}
|
||||||
|
|
|
@ -26,12 +26,12 @@ pub fn exhaustive_match(e: E) -> u8 {
|
||||||
// CHECK-NEXT: store i8 1, ptr %_0, align 1
|
// CHECK-NEXT: store i8 1, ptr %_0, align 1
|
||||||
// CHECK-NEXT: br label %[[EXIT]]
|
// CHECK-NEXT: br label %[[EXIT]]
|
||||||
// CHECK: [[C]]:
|
// CHECK: [[C]]:
|
||||||
// CHECK-NEXT: store i8 2, ptr %_0, align 1
|
// CHECK-NEXT: store i8 3, ptr %_0, align 1
|
||||||
// CHECK-NEXT: br label %[[EXIT]]
|
// CHECK-NEXT: br label %[[EXIT]]
|
||||||
match e {
|
match e {
|
||||||
E::A => 0,
|
E::A => 0,
|
||||||
E::B => 1,
|
E::B => 1,
|
||||||
E::C => 2,
|
E::C => 3,
|
||||||
}
|
}
|
||||||
}
|
}
|
||||||
|
|
||||||
|
|
|
@ -0,0 +1,47 @@
|
||||||
|
- // MIR for `match_i128_u128` before MatchBranchSimplification
|
||||||
|
+ // MIR for `match_i128_u128` after MatchBranchSimplification
|
||||||
|
|
||||||
|
fn match_i128_u128(_1: EnumAi128) -> u128 {
|
||||||
|
debug i => _1;
|
||||||
|
let mut _0: u128;
|
||||||
|
let mut _2: i128;
|
||||||
|
+ let mut _3: i128;
|
||||||
|
|
||||||
|
bb0: {
|
||||||
|
_2 = discriminant(_1);
|
||||||
|
- switchInt(move _2) -> [1: bb3, 2: bb4, 3: bb5, 340282366920938463463374607431768211455: bb2, otherwise: bb1];
|
||||||
|
- }
|
||||||
|
-
|
||||||
|
- bb1: {
|
||||||
|
- unreachable;
|
||||||
|
- }
|
||||||
|
-
|
||||||
|
- bb2: {
|
||||||
|
- _0 = const core::num::<impl u128>::MAX;
|
||||||
|
- goto -> bb6;
|
||||||
|
- }
|
||||||
|
-
|
||||||
|
- bb3: {
|
||||||
|
- _0 = const 1_u128;
|
||||||
|
- goto -> bb6;
|
||||||
|
- }
|
||||||
|
-
|
||||||
|
- bb4: {
|
||||||
|
- _0 = const 2_u128;
|
||||||
|
- goto -> bb6;
|
||||||
|
- }
|
||||||
|
-
|
||||||
|
- bb5: {
|
||||||
|
- _0 = const 3_u128;
|
||||||
|
- goto -> bb6;
|
||||||
|
- }
|
||||||
|
-
|
||||||
|
- bb6: {
|
||||||
|
+ StorageLive(_3);
|
||||||
|
+ _3 = move _2;
|
||||||
|
+ _0 = _3 as u128 (IntToInt);
|
||||||
|
+ StorageDead(_3);
|
||||||
|
return;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
|
@ -0,0 +1,42 @@
|
||||||
|
- // MIR for `match_i16_i8` before MatchBranchSimplification
|
||||||
|
+ // MIR for `match_i16_i8` after MatchBranchSimplification
|
||||||
|
|
||||||
|
fn match_i16_i8(_1: EnumAi16) -> i8 {
|
||||||
|
debug i => _1;
|
||||||
|
let mut _0: i8;
|
||||||
|
let mut _2: i16;
|
||||||
|
+ let mut _3: i16;
|
||||||
|
|
||||||
|
bb0: {
|
||||||
|
_2 = discriminant(_1);
|
||||||
|
- switchInt(move _2) -> [65535: bb3, 2: bb4, 65533: bb2, otherwise: bb1];
|
||||||
|
- }
|
||||||
|
-
|
||||||
|
- bb1: {
|
||||||
|
- unreachable;
|
||||||
|
- }
|
||||||
|
-
|
||||||
|
- bb2: {
|
||||||
|
- _0 = const -3_i8;
|
||||||
|
- goto -> bb5;
|
||||||
|
- }
|
||||||
|
-
|
||||||
|
- bb3: {
|
||||||
|
- _0 = const -1_i8;
|
||||||
|
- goto -> bb5;
|
||||||
|
- }
|
||||||
|
-
|
||||||
|
- bb4: {
|
||||||
|
- _0 = const 2_i8;
|
||||||
|
- goto -> bb5;
|
||||||
|
- }
|
||||||
|
-
|
||||||
|
- bb5: {
|
||||||
|
+ StorageLive(_3);
|
||||||
|
+ _3 = move _2;
|
||||||
|
+ _0 = _3 as i8 (IntToInt);
|
||||||
|
+ StorageDead(_3);
|
||||||
|
return;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
|
@ -0,0 +1,42 @@
|
||||||
|
- // MIR for `match_i8_i16` before MatchBranchSimplification
|
||||||
|
+ // MIR for `match_i8_i16` after MatchBranchSimplification
|
||||||
|
|
||||||
|
fn match_i8_i16(_1: EnumAi8) -> i16 {
|
||||||
|
debug i => _1;
|
||||||
|
let mut _0: i16;
|
||||||
|
let mut _2: i8;
|
||||||
|
+ let mut _3: i8;
|
||||||
|
|
||||||
|
bb0: {
|
||||||
|
_2 = discriminant(_1);
|
||||||
|
- switchInt(move _2) -> [255: bb3, 2: bb4, 253: bb2, otherwise: bb1];
|
||||||
|
- }
|
||||||
|
-
|
||||||
|
- bb1: {
|
||||||
|
- unreachable;
|
||||||
|
- }
|
||||||
|
-
|
||||||
|
- bb2: {
|
||||||
|
- _0 = const -3_i16;
|
||||||
|
- goto -> bb5;
|
||||||
|
- }
|
||||||
|
-
|
||||||
|
- bb3: {
|
||||||
|
- _0 = const -1_i16;
|
||||||
|
- goto -> bb5;
|
||||||
|
- }
|
||||||
|
-
|
||||||
|
- bb4: {
|
||||||
|
- _0 = const 2_i16;
|
||||||
|
- goto -> bb5;
|
||||||
|
- }
|
||||||
|
-
|
||||||
|
- bb5: {
|
||||||
|
+ StorageLive(_3);
|
||||||
|
+ _3 = move _2;
|
||||||
|
+ _0 = _3 as i16 (IntToInt);
|
||||||
|
+ StorageDead(_3);
|
||||||
|
return;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
|
@ -0,0 +1,37 @@
|
||||||
|
- // MIR for `match_i8_i16_failed` before MatchBranchSimplification
|
||||||
|
+ // MIR for `match_i8_i16_failed` after MatchBranchSimplification
|
||||||
|
|
||||||
|
fn match_i8_i16_failed(_1: EnumAi8) -> i16 {
|
||||||
|
debug i => _1;
|
||||||
|
let mut _0: i16;
|
||||||
|
let mut _2: i8;
|
||||||
|
|
||||||
|
bb0: {
|
||||||
|
_2 = discriminant(_1);
|
||||||
|
switchInt(move _2) -> [255: bb3, 2: bb4, 253: bb2, otherwise: bb1];
|
||||||
|
}
|
||||||
|
|
||||||
|
bb1: {
|
||||||
|
unreachable;
|
||||||
|
}
|
||||||
|
|
||||||
|
bb2: {
|
||||||
|
_0 = const 3_i16;
|
||||||
|
goto -> bb5;
|
||||||
|
}
|
||||||
|
|
||||||
|
bb3: {
|
||||||
|
_0 = const -1_i16;
|
||||||
|
goto -> bb5;
|
||||||
|
}
|
||||||
|
|
||||||
|
bb4: {
|
||||||
|
_0 = const 2_i16;
|
||||||
|
goto -> bb5;
|
||||||
|
}
|
||||||
|
|
||||||
|
bb5: {
|
||||||
|
return;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
|
@ -0,0 +1,37 @@
|
||||||
|
- // MIR for `match_u8_i16` before MatchBranchSimplification
|
||||||
|
+ // MIR for `match_u8_i16` after MatchBranchSimplification
|
||||||
|
|
||||||
|
fn match_u8_i16(_1: EnumAu8) -> i16 {
|
||||||
|
debug i => _1;
|
||||||
|
let mut _0: i16;
|
||||||
|
let mut _2: u8;
|
||||||
|
+ let mut _3: u8;
|
||||||
|
|
||||||
|
bb0: {
|
||||||
|
_2 = discriminant(_1);
|
||||||
|
- switchInt(move _2) -> [1: bb3, 2: bb2, otherwise: bb1];
|
||||||
|
- }
|
||||||
|
-
|
||||||
|
- bb1: {
|
||||||
|
- unreachable;
|
||||||
|
- }
|
||||||
|
-
|
||||||
|
- bb2: {
|
||||||
|
- _0 = const 2_i16;
|
||||||
|
- goto -> bb4;
|
||||||
|
- }
|
||||||
|
-
|
||||||
|
- bb3: {
|
||||||
|
- _0 = const 1_i16;
|
||||||
|
- goto -> bb4;
|
||||||
|
- }
|
||||||
|
-
|
||||||
|
- bb4: {
|
||||||
|
+ StorageLive(_3);
|
||||||
|
+ _3 = move _2;
|
||||||
|
+ _0 = _3 as i16 (IntToInt);
|
||||||
|
+ StorageDead(_3);
|
||||||
|
return;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
|
@ -0,0 +1,26 @@
|
||||||
|
- // MIR for `match_u8_i16_2` before MatchBranchSimplification
|
||||||
|
+ // MIR for `match_u8_i16_2` after MatchBranchSimplification
|
||||||
|
|
||||||
|
fn match_u8_i16_2(_1: EnumAu8) -> i16 {
|
||||||
|
let mut _0: i16;
|
||||||
|
let mut _2: u8;
|
||||||
|
|
||||||
|
bb0: {
|
||||||
|
_2 = discriminant(_1);
|
||||||
|
switchInt(_2) -> [1: bb3, 2: bb1, otherwise: bb2];
|
||||||
|
}
|
||||||
|
|
||||||
|
bb1: {
|
||||||
|
_0 = const 2_i16;
|
||||||
|
goto -> bb3;
|
||||||
|
}
|
||||||
|
|
||||||
|
bb2: {
|
||||||
|
unreachable;
|
||||||
|
}
|
||||||
|
|
||||||
|
bb3: {
|
||||||
|
return;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
|
@ -0,0 +1,32 @@
|
||||||
|
- // MIR for `match_u8_i16_failed` before MatchBranchSimplification
|
||||||
|
+ // MIR for `match_u8_i16_failed` after MatchBranchSimplification
|
||||||
|
|
||||||
|
fn match_u8_i16_failed(_1: EnumAu8) -> i16 {
|
||||||
|
debug i => _1;
|
||||||
|
let mut _0: i16;
|
||||||
|
let mut _2: u8;
|
||||||
|
|
||||||
|
bb0: {
|
||||||
|
_2 = discriminant(_1);
|
||||||
|
switchInt(move _2) -> [1: bb3, 2: bb2, otherwise: bb1];
|
||||||
|
}
|
||||||
|
|
||||||
|
bb1: {
|
||||||
|
unreachable;
|
||||||
|
}
|
||||||
|
|
||||||
|
bb2: {
|
||||||
|
_0 = const 3_i16;
|
||||||
|
goto -> bb4;
|
||||||
|
}
|
||||||
|
|
||||||
|
bb3: {
|
||||||
|
_0 = const 1_i16;
|
||||||
|
goto -> bb4;
|
||||||
|
}
|
||||||
|
|
||||||
|
bb4: {
|
||||||
|
return;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
|
@ -0,0 +1,31 @@
|
||||||
|
- // MIR for `match_u8_i16_fallback` before MatchBranchSimplification
|
||||||
|
+ // MIR for `match_u8_i16_fallback` after MatchBranchSimplification
|
||||||
|
|
||||||
|
fn match_u8_i16_fallback(_1: u8) -> i16 {
|
||||||
|
debug i => _1;
|
||||||
|
let mut _0: i16;
|
||||||
|
|
||||||
|
bb0: {
|
||||||
|
switchInt(_1) -> [1: bb2, 2: bb3, otherwise: bb1];
|
||||||
|
}
|
||||||
|
|
||||||
|
bb1: {
|
||||||
|
_0 = const 3_i16;
|
||||||
|
goto -> bb4;
|
||||||
|
}
|
||||||
|
|
||||||
|
bb2: {
|
||||||
|
_0 = const 1_i16;
|
||||||
|
goto -> bb4;
|
||||||
|
}
|
||||||
|
|
||||||
|
bb3: {
|
||||||
|
_0 = const 2_i16;
|
||||||
|
goto -> bb4;
|
||||||
|
}
|
||||||
|
|
||||||
|
bb4: {
|
||||||
|
return;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
|
@ -0,0 +1,42 @@
|
||||||
|
- // MIR for `match_u8_u16` before MatchBranchSimplification
|
||||||
|
+ // MIR for `match_u8_u16` after MatchBranchSimplification
|
||||||
|
|
||||||
|
fn match_u8_u16(_1: EnumBu8) -> u16 {
|
||||||
|
debug i => _1;
|
||||||
|
let mut _0: u16;
|
||||||
|
let mut _2: u8;
|
||||||
|
+ let mut _3: u8;
|
||||||
|
|
||||||
|
bb0: {
|
||||||
|
_2 = discriminant(_1);
|
||||||
|
- switchInt(move _2) -> [1: bb3, 2: bb4, 5: bb2, otherwise: bb1];
|
||||||
|
- }
|
||||||
|
-
|
||||||
|
- bb1: {
|
||||||
|
- unreachable;
|
||||||
|
- }
|
||||||
|
-
|
||||||
|
- bb2: {
|
||||||
|
- _0 = const 5_u16;
|
||||||
|
- goto -> bb5;
|
||||||
|
- }
|
||||||
|
-
|
||||||
|
- bb3: {
|
||||||
|
- _0 = const 1_u16;
|
||||||
|
- goto -> bb5;
|
||||||
|
- }
|
||||||
|
-
|
||||||
|
- bb4: {
|
||||||
|
- _0 = const 2_u16;
|
||||||
|
- goto -> bb5;
|
||||||
|
- }
|
||||||
|
-
|
||||||
|
- bb5: {
|
||||||
|
+ StorageLive(_3);
|
||||||
|
+ _3 = move _2;
|
||||||
|
+ _0 = _3 as u16 (IntToInt);
|
||||||
|
+ StorageDead(_3);
|
||||||
|
return;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
|
@ -0,0 +1,37 @@
|
||||||
|
- // MIR for `match_u8_u16_2` before MatchBranchSimplification
|
||||||
|
+ // MIR for `match_u8_u16_2` after MatchBranchSimplification
|
||||||
|
|
||||||
|
fn match_u8_u16_2(_1: EnumBu8) -> i16 {
|
||||||
|
let mut _0: i16;
|
||||||
|
let mut _2: u8;
|
||||||
|
|
||||||
|
bb0: {
|
||||||
|
_2 = discriminant(_1);
|
||||||
|
switchInt(_2) -> [1: bb1, 2: bb2, 5: bb3, otherwise: bb4];
|
||||||
|
}
|
||||||
|
|
||||||
|
bb1: {
|
||||||
|
_0 = const 1_i16;
|
||||||
|
goto -> bb5;
|
||||||
|
}
|
||||||
|
|
||||||
|
bb2: {
|
||||||
|
_0 = const 2_i16;
|
||||||
|
goto -> bb5;
|
||||||
|
}
|
||||||
|
|
||||||
|
bb3: {
|
||||||
|
_0 = const 5_i16;
|
||||||
|
_0 = const 5_i16;
|
||||||
|
goto -> bb5;
|
||||||
|
}
|
||||||
|
|
||||||
|
bb4: {
|
||||||
|
unreachable;
|
||||||
|
}
|
||||||
|
|
||||||
|
bb5: {
|
||||||
|
return;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
|
@ -1,18 +1,28 @@
|
||||||
// skip-filecheck
|
|
||||||
//@ unit-test: MatchBranchSimplification
|
//@ unit-test: MatchBranchSimplification
|
||||||
|
|
||||||
|
#![feature(repr128)]
|
||||||
|
#![feature(core_intrinsics)]
|
||||||
|
#![feature(custom_mir)]
|
||||||
|
|
||||||
|
use std::intrinsics::mir::*;
|
||||||
|
|
||||||
// EMIT_MIR matches_reduce_branches.foo.MatchBranchSimplification.diff
|
// EMIT_MIR matches_reduce_branches.foo.MatchBranchSimplification.diff
|
||||||
// EMIT_MIR matches_reduce_branches.bar.MatchBranchSimplification.diff
|
|
||||||
// EMIT_MIR matches_reduce_branches.match_nested_if.MatchBranchSimplification.diff
|
|
||||||
|
|
||||||
fn foo(bar: Option<()>) {
|
fn foo(bar: Option<()>) {
|
||||||
|
// CHECK-LABEL: fn foo(
|
||||||
|
// CHECK: = Eq(
|
||||||
|
// CHECK: switchInt
|
||||||
|
// CHECK-NOT: switchInt
|
||||||
if matches!(bar, None) {
|
if matches!(bar, None) {
|
||||||
()
|
()
|
||||||
}
|
}
|
||||||
}
|
}
|
||||||
|
|
||||||
|
// EMIT_MIR matches_reduce_branches.bar.MatchBranchSimplification.diff
|
||||||
fn bar(i: i32) -> (bool, bool, bool, bool) {
|
fn bar(i: i32) -> (bool, bool, bool, bool) {
|
||||||
|
// CHECK-LABEL: fn bar(
|
||||||
|
// CHECK: = Ne(
|
||||||
|
// CHECK: = Eq(
|
||||||
|
// CHECK-NOT: switchInt
|
||||||
let a;
|
let a;
|
||||||
let b;
|
let b;
|
||||||
let c;
|
let c;
|
||||||
|
@ -38,7 +48,10 @@ fn bar(i: i32) -> (bool, bool, bool, bool) {
|
||||||
(a, b, c, d)
|
(a, b, c, d)
|
||||||
}
|
}
|
||||||
|
|
||||||
|
// EMIT_MIR matches_reduce_branches.match_nested_if.MatchBranchSimplification.diff
|
||||||
fn match_nested_if() -> bool {
|
fn match_nested_if() -> bool {
|
||||||
|
// CHECK-LABEL: fn match_nested_if(
|
||||||
|
// CHECK-NOT: switchInt
|
||||||
let val = match () {
|
let val = match () {
|
||||||
() if if if if true { true } else { false } { true } else { false } {
|
() if if if if true { true } else { false } { true } else { false } {
|
||||||
true
|
true
|
||||||
|
@ -53,9 +66,221 @@ fn match_nested_if() -> bool {
|
||||||
val
|
val
|
||||||
}
|
}
|
||||||
|
|
||||||
|
#[repr(u8)]
|
||||||
|
enum EnumAu8 {
|
||||||
|
A = 1,
|
||||||
|
B = 2,
|
||||||
|
}
|
||||||
|
|
||||||
|
// EMIT_MIR matches_reduce_branches.match_u8_i16.MatchBranchSimplification.diff
|
||||||
|
fn match_u8_i16(i: EnumAu8) -> i16 {
|
||||||
|
// CHECK-LABEL: fn match_u8_i16(
|
||||||
|
// CHECK-NOT: switchInt
|
||||||
|
// CHECK: _0 = _3 as i16 (IntToInt);
|
||||||
|
// CHECH: return
|
||||||
|
match i {
|
||||||
|
EnumAu8::A => 1,
|
||||||
|
EnumAu8::B => 2,
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
// EMIT_MIR matches_reduce_branches.match_u8_i16_2.MatchBranchSimplification.diff
|
||||||
|
// Check for different instruction lengths
|
||||||
|
#[custom_mir(dialect = "built")]
|
||||||
|
fn match_u8_i16_2(i: EnumAu8) -> i16 {
|
||||||
|
// CHECK-LABEL: fn match_u8_i16_2(
|
||||||
|
// CHECK: switchInt
|
||||||
|
mir!(
|
||||||
|
{
|
||||||
|
let a = Discriminant(i);
|
||||||
|
match a {
|
||||||
|
1 => bb1,
|
||||||
|
2 => bb2,
|
||||||
|
_ => unreachable_bb,
|
||||||
|
}
|
||||||
|
}
|
||||||
|
bb1 = {
|
||||||
|
Goto(ret)
|
||||||
|
}
|
||||||
|
bb2 = {
|
||||||
|
RET = 2;
|
||||||
|
Goto(ret)
|
||||||
|
}
|
||||||
|
unreachable_bb = {
|
||||||
|
Unreachable()
|
||||||
|
}
|
||||||
|
ret = {
|
||||||
|
Return()
|
||||||
|
}
|
||||||
|
)
|
||||||
|
}
|
||||||
|
|
||||||
|
// EMIT_MIR matches_reduce_branches.match_u8_i16_failed.MatchBranchSimplification.diff
|
||||||
|
fn match_u8_i16_failed(i: EnumAu8) -> i16 {
|
||||||
|
// CHECK-LABEL: fn match_u8_i16_failed(
|
||||||
|
// CHECK: switchInt
|
||||||
|
match i {
|
||||||
|
EnumAu8::A => 1,
|
||||||
|
EnumAu8::B => 3,
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
// EMIT_MIR matches_reduce_branches.match_u8_i16_fallback.MatchBranchSimplification.diff
|
||||||
|
fn match_u8_i16_fallback(i: u8) -> i16 {
|
||||||
|
// CHECK-LABEL: fn match_u8_i16_fallback(
|
||||||
|
// CHECK: switchInt
|
||||||
|
match i {
|
||||||
|
1 => 1,
|
||||||
|
2 => 2,
|
||||||
|
_ => 3,
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
#[repr(u8)]
|
||||||
|
enum EnumBu8 {
|
||||||
|
A = 1,
|
||||||
|
B = 2,
|
||||||
|
C = 5,
|
||||||
|
}
|
||||||
|
|
||||||
|
// EMIT_MIR matches_reduce_branches.match_u8_u16.MatchBranchSimplification.diff
|
||||||
|
fn match_u8_u16(i: EnumBu8) -> u16 {
|
||||||
|
// CHECK-LABEL: fn match_u8_u16(
|
||||||
|
// CHECK-NOT: switchInt
|
||||||
|
// CHECK: _0 = _3 as u16 (IntToInt);
|
||||||
|
// CHECH: return
|
||||||
|
match i {
|
||||||
|
EnumBu8::A => 1,
|
||||||
|
EnumBu8::B => 2,
|
||||||
|
EnumBu8::C => 5,
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
// EMIT_MIR matches_reduce_branches.match_u8_u16_2.MatchBranchSimplification.diff
|
||||||
|
// Check for different instruction lengths
|
||||||
|
#[custom_mir(dialect = "built")]
|
||||||
|
fn match_u8_u16_2(i: EnumBu8) -> i16 {
|
||||||
|
// CHECK-LABEL: fn match_u8_u16_2(
|
||||||
|
// CHECK: switchInt
|
||||||
|
mir!(
|
||||||
|
{
|
||||||
|
let a = Discriminant(i);
|
||||||
|
match a {
|
||||||
|
1 => bb1,
|
||||||
|
2 => bb2,
|
||||||
|
5 => bb5,
|
||||||
|
_ => unreachable_bb,
|
||||||
|
}
|
||||||
|
}
|
||||||
|
bb1 = {
|
||||||
|
RET = 1;
|
||||||
|
Goto(ret)
|
||||||
|
}
|
||||||
|
bb2 = {
|
||||||
|
RET = 2;
|
||||||
|
Goto(ret)
|
||||||
|
}
|
||||||
|
bb5 = {
|
||||||
|
RET = 5;
|
||||||
|
RET = 5;
|
||||||
|
Goto(ret)
|
||||||
|
}
|
||||||
|
unreachable_bb = {
|
||||||
|
Unreachable()
|
||||||
|
}
|
||||||
|
ret = {
|
||||||
|
Return()
|
||||||
|
}
|
||||||
|
)
|
||||||
|
}
|
||||||
|
|
||||||
|
#[repr(i8)]
|
||||||
|
enum EnumAi8 {
|
||||||
|
A = -1,
|
||||||
|
B = 2,
|
||||||
|
C = -3,
|
||||||
|
}
|
||||||
|
|
||||||
|
// EMIT_MIR matches_reduce_branches.match_i8_i16.MatchBranchSimplification.diff
|
||||||
|
fn match_i8_i16(i: EnumAi8) -> i16 {
|
||||||
|
// CHECK-LABEL: fn match_i8_i16(
|
||||||
|
// CHECK-NOT: switchInt
|
||||||
|
// CHECK: _0 = _3 as i16 (IntToInt);
|
||||||
|
// CHECH: return
|
||||||
|
match i {
|
||||||
|
EnumAi8::A => -1,
|
||||||
|
EnumAi8::B => 2,
|
||||||
|
EnumAi8::C => -3,
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
// EMIT_MIR matches_reduce_branches.match_i8_i16_failed.MatchBranchSimplification.diff
|
||||||
|
fn match_i8_i16_failed(i: EnumAi8) -> i16 {
|
||||||
|
// CHECK-LABEL: fn match_i8_i16_failed(
|
||||||
|
// CHECK: switchInt
|
||||||
|
match i {
|
||||||
|
EnumAi8::A => -1,
|
||||||
|
EnumAi8::B => 2,
|
||||||
|
EnumAi8::C => 3,
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
#[repr(i16)]
|
||||||
|
enum EnumAi16 {
|
||||||
|
A = -1,
|
||||||
|
B = 2,
|
||||||
|
C = -3,
|
||||||
|
}
|
||||||
|
|
||||||
|
// EMIT_MIR matches_reduce_branches.match_i16_i8.MatchBranchSimplification.diff
|
||||||
|
fn match_i16_i8(i: EnumAi16) -> i8 {
|
||||||
|
// CHECK-LABEL: fn match_i16_i8(
|
||||||
|
// CHECK-NOT: switchInt
|
||||||
|
// CHECK: _0 = _3 as i8 (IntToInt);
|
||||||
|
// CHECH: return
|
||||||
|
match i {
|
||||||
|
EnumAi16::A => -1,
|
||||||
|
EnumAi16::B => 2,
|
||||||
|
EnumAi16::C => -3,
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
#[repr(i128)]
|
||||||
|
enum EnumAi128 {
|
||||||
|
A = 1,
|
||||||
|
B = 2,
|
||||||
|
C = 3,
|
||||||
|
D = -1,
|
||||||
|
}
|
||||||
|
|
||||||
|
// EMIT_MIR matches_reduce_branches.match_i128_u128.MatchBranchSimplification.diff
|
||||||
|
fn match_i128_u128(i: EnumAi128) -> u128 {
|
||||||
|
// CHECK-LABEL: fn match_i128_u128(
|
||||||
|
// CHECK-NOT: switchInt
|
||||||
|
// CHECK: _0 = _3 as u128 (IntToInt);
|
||||||
|
// CHECH: return
|
||||||
|
match i {
|
||||||
|
EnumAi128::A => 1,
|
||||||
|
EnumAi128::B => 2,
|
||||||
|
EnumAi128::C => 3,
|
||||||
|
EnumAi128::D => u128::MAX,
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
fn main() {
|
fn main() {
|
||||||
let _ = foo(None);
|
let _ = foo(None);
|
||||||
let _ = foo(Some(()));
|
let _ = foo(Some(()));
|
||||||
let _ = bar(0);
|
let _ = bar(0);
|
||||||
let _ = match_nested_if();
|
let _ = match_nested_if();
|
||||||
|
let _ = match_u8_i16(EnumAu8::A);
|
||||||
|
let _ = match_u8_i16_2(EnumAu8::A);
|
||||||
|
let _ = match_u8_i16_failed(EnumAu8::A);
|
||||||
|
let _ = match_u8_i16_fallback(1);
|
||||||
|
let _ = match_u8_u16(EnumBu8::A);
|
||||||
|
let _ = match_u8_u16_2(EnumBu8::A);
|
||||||
|
let _ = match_i8_i16(EnumAi8::A);
|
||||||
|
let _ = match_i8_i16_failed(EnumAi8::A);
|
||||||
|
let _ = match_i8_i16(EnumAi8::A);
|
||||||
|
let _ = match_i16_i8(EnumAi16::A);
|
||||||
|
let _ = match_i128_u128(EnumAi128::A);
|
||||||
}
|
}
|
||||||
|
|
|
@ -5,27 +5,32 @@
|
||||||
debug e => _1;
|
debug e => _1;
|
||||||
let mut _0: u8;
|
let mut _0: u8;
|
||||||
let mut _2: isize;
|
let mut _2: isize;
|
||||||
|
+ let mut _3: isize;
|
||||||
|
|
||||||
bb0: {
|
bb0: {
|
||||||
_2 = discriminant(_1);
|
_2 = discriminant(_1);
|
||||||
switchInt(move _2) -> [0: bb3, 1: bb2, otherwise: bb1];
|
- switchInt(move _2) -> [0: bb3, 1: bb2, otherwise: bb1];
|
||||||
}
|
- }
|
||||||
|
-
|
||||||
bb1: {
|
- bb1: {
|
||||||
unreachable;
|
- unreachable;
|
||||||
}
|
- }
|
||||||
|
-
|
||||||
bb2: {
|
- bb2: {
|
||||||
_0 = const 1_u8;
|
- _0 = const 1_u8;
|
||||||
goto -> bb4;
|
- goto -> bb4;
|
||||||
}
|
- }
|
||||||
|
-
|
||||||
bb3: {
|
- bb3: {
|
||||||
_0 = const 0_u8;
|
- _0 = const 0_u8;
|
||||||
goto -> bb4;
|
- goto -> bb4;
|
||||||
}
|
- }
|
||||||
|
-
|
||||||
bb4: {
|
- bb4: {
|
||||||
|
+ StorageLive(_3);
|
||||||
|
+ _3 = move _2;
|
||||||
|
+ _0 = _3 as u8 (IntToInt);
|
||||||
|
+ StorageDead(_3);
|
||||||
return;
|
return;
|
||||||
}
|
}
|
||||||
}
|
}
|
||||||
|
|
|
@ -5,27 +5,32 @@
|
||||||
debug e => _1;
|
debug e => _1;
|
||||||
let mut _0: i8;
|
let mut _0: i8;
|
||||||
let mut _2: isize;
|
let mut _2: isize;
|
||||||
|
+ let mut _3: isize;
|
||||||
|
|
||||||
bb0: {
|
bb0: {
|
||||||
_2 = discriminant(_1);
|
_2 = discriminant(_1);
|
||||||
switchInt(move _2) -> [0: bb3, 1: bb2, otherwise: bb1];
|
- switchInt(move _2) -> [0: bb3, 1: bb2, otherwise: bb1];
|
||||||
}
|
- }
|
||||||
|
-
|
||||||
bb1: {
|
- bb1: {
|
||||||
unreachable;
|
- unreachable;
|
||||||
}
|
- }
|
||||||
|
-
|
||||||
bb2: {
|
- bb2: {
|
||||||
_0 = const 1_i8;
|
- _0 = const 1_i8;
|
||||||
goto -> bb4;
|
- goto -> bb4;
|
||||||
}
|
- }
|
||||||
|
-
|
||||||
bb3: {
|
- bb3: {
|
||||||
_0 = const 0_i8;
|
- _0 = const 0_i8;
|
||||||
goto -> bb4;
|
- goto -> bb4;
|
||||||
}
|
- }
|
||||||
|
-
|
||||||
bb4: {
|
- bb4: {
|
||||||
|
+ StorageLive(_3);
|
||||||
|
+ _3 = move _2;
|
||||||
|
+ _0 = _3 as i8 (IntToInt);
|
||||||
|
+ StorageDead(_3);
|
||||||
return;
|
return;
|
||||||
}
|
}
|
||||||
}
|
}
|
||||||
|
|
Loading…
Reference in New Issue