<commit_before>use crate::utils::{
    fn_has_unsatisfiable_preds, has_drop, is_copy, is_type_diagnostic_item, match_def_path, match_type, paths,
    snippet_opt, span_lint_hir, span_lint_hir_and_then, walk_ptrs_ty_depth,
};
use if_chain::if_chain;
use rustc_data_structures::{fx::FxHashMap, transitive_relation::TransitiveRelation};
use rustc_errors::Applicability;
use rustc_hir::intravisit::FnKind;
use rustc_hir::{def_id, Body, FnDecl, HirId};
use rustc_index::bit_set::{BitSet, HybridBitSet};
use rustc_lint::{LateContext, LateLintPass};
use rustc_middle::mir::{
    self, traversal,
    visit::{MutatingUseContext, NonMutatingUseContext, PlaceContext, Visitor as _},
};
use rustc_middle::ty::{self, fold::TypeVisitor, Ty};
use rustc_mir::dataflow::{Analysis, AnalysisDomain, GenKill, GenKillAnalysis, ResultsCursor};
use rustc_session::{declare_lint_pass, declare_tool_lint};
use rustc_span::source_map::{BytePos, Span};
use std::convert::TryFrom;

macro_rules! unwrap_or_continue {
    ($x:expr) => {
        match $x {
            Some(x) => x,
            None => continue,
        }
    };
}

declare_clippy_lint! {
    /// **What it does:** Checks for a redundant `clone()` (and its relatives) which clones an owned
    /// value that is going to be dropped without further use.
    ///
    /// **Why is this bad?** It is not always possible for the compiler to eliminate useless
    /// allocations and deallocations generated by redundant `clone()`s.
    ///
    /// **Known problems:**
    ///
    /// False-negatives: analysis performed by this lint is conservative and limited.
    ///
    /// **Example:**
    /// ```rust
    /// # use std::path::Path;
    /// # #[derive(Clone)]
    /// # struct Foo;
    /// # impl Foo {
    /// #     fn new() -> Self { Foo {} }
    /// # }
    /// # fn call(x: Foo) {}
    /// {
    ///     let x = Foo::new();
    ///     call(x.clone());
    ///     call(x.clone()); // this can just pass `x`
    /// }
    ///
    /// ["lorem", "ipsum"].join(" ").to_string();
    ///
    /// Path::new("/a/b").join("c").to_path_buf();
    /// ```
    pub REDUNDANT_CLONE,
    perf,
    "`clone()` of an owned value that is going to be dropped immediately"
}

declare_lint_pass!(RedundantClone => [REDUNDANT_CLONE]);

impl<'tcx> LateLintPass<'tcx> for RedundantClone {
    #[allow(clippy::too_many_lines)]
    fn check_fn(
        &mut self,
        cx: &LateContext<'tcx>,
        _: FnKind<'tcx>,
        _: &'tcx FnDecl<'_>,
        body: &'tcx Body<'_>,
        _: Span,
        _: HirId,
    ) {
        let def_id = cx.tcx.hir().body_owner_def_id(body.id());

        // Building MIR for `fn`s with unsatisfiable preds results in ICE.
        if fn_has_unsatisfiable_preds(cx, def_id.to_def_id()) {
            return;
        }

        let mir = cx.tcx.optimized_mir(def_id.to_def_id());

        let maybe_storage_live_result = MaybeStorageLive
            .into_engine(cx.tcx, mir, def_id.to_def_id())
            .iterate_to_fixpoint()
            .into_results_cursor(mir);
        let mut possible_borrower = {
            let mut vis = PossibleBorrowerVisitor::new(cx, mir);
            vis.visit_body(&mir);
            vis.into_map(cx, maybe_storage_live_result)
        };

        for (bb, bbdata) in mir.basic_blocks().iter_enumerated() {
            let terminator = bbdata.terminator();

            if terminator.source_info.span.from_expansion() {
                continue;
            }

            // Give up on loops
            if terminator.successors().any(|s| *s == bb) {
                continue;
            }

            let (fn_def_id, arg, arg_ty, clone_ret) =
                unwrap_or_continue!(is_call_with_ref_arg(cx, mir, &terminator.kind));

            let from_borrow = match_def_path(cx, fn_def_id, &paths::CLONE_TRAIT_METHOD)
                || match_def_path(cx, fn_def_id, &paths::TO_OWNED_METHOD)
                || (match_def_path(cx, fn_def_id, &paths::TO_STRING_METHOD)
                    && is_type_diagnostic_item(cx, arg_ty, sym!(string_type)));

            let from_deref = !from_borrow
                && (match_def_path(cx, fn_def_id, &paths::PATH_TO_PATH_BUF)
                    || match_def_path(cx, fn_def_id, &paths::OS_STR_TO_OS_STRING));<commit_msg>Rollup merge of #76724 - ecstatic-morse:dataflow-pass-names, r=lcnr<commit_after>use crate::utils::{
    fn_has_unsatisfiable_preds, has_drop, is_copy, is_type_diagnostic_item, match_def_path, match_type, paths,
    snippet_opt, span_lint_hir, span_lint_hir_and_then, walk_ptrs_ty_depth,
};
use if_chain::if_chain;
use rustc_data_structures::{fx::FxHashMap, transitive_relation::TransitiveRelation};
use rustc_errors::Applicability;
use rustc_hir::intravisit::FnKind;
use rustc_hir::{def_id, Body, FnDecl, HirId};
use rustc_index::bit_set::{BitSet, HybridBitSet};
use rustc_lint::{LateContext, LateLintPass};
use rustc_middle::mir::{
    self, traversal,
    visit::{MutatingUseContext, NonMutatingUseContext, PlaceContext, Visitor as _},
};
use rustc_middle::ty::{self, fold::TypeVisitor, Ty};
use rustc_mir::dataflow::{Analysis, AnalysisDomain, GenKill, GenKillAnalysis, ResultsCursor};
use rustc_session::{declare_lint_pass, declare_tool_lint};
use rustc_span::source_map::{BytePos, Span};
use std::convert::TryFrom;

macro_rules! unwrap_or_continue {
    ($x:expr) => {
        match $x {
            Some(x) => x,
            None => continue,
        }
    };
}

declare_clippy_lint! {
    /// **What it does:** Checks for a redundant `clone()` (and its relatives) which clones an owned
    /// value that is going to be dropped without further use.
    ///
    /// **Why is this bad?** It is not always possible for the compiler to eliminate useless
    /// allocations and deallocations generated by redundant `clone()`s.
    ///
    /// **Known problems:**
    ///
    /// False-negatives: analysis performed by this lint is conservative and limited.
    ///
    /// **Example:**
    /// ```rust
    /// # use std::path::Path;
    /// # #[derive(Clone)]
    /// # struct Foo;
    /// # impl Foo {
    /// #     fn new() -> Self { Foo {} }
    /// # }
    /// # fn call(x: Foo) {}
    /// {
    ///     let x = Foo::new();
    ///     call(x.clone());
    ///     call(x.clone()); // this can just pass `x`
    /// }
    ///
    /// ["lorem", "ipsum"].join(" ").to_string();
    ///
    /// Path::new("/a/b").join("c").to_path_buf();
    /// ```
    pub REDUNDANT_CLONE,
    perf,
    "`clone()` of an owned value that is going to be dropped immediately"
}

declare_lint_pass!(RedundantClone => [REDUNDANT_CLONE]);

impl<'tcx> LateLintPass<'tcx> for RedundantClone {
    #[allow(clippy::too_many_lines)]
    fn check_fn(
        &mut self,
        cx: &LateContext<'tcx>,
        _: FnKind<'tcx>,
        _: &'tcx FnDecl<'_>,
        body: &'tcx Body<'_>,
        _: Span,
        _: HirId,
    ) {
        let def_id = cx.tcx.hir().body_owner_def_id(body.id());

        // Building MIR for `fn`s with unsatisfiable preds results in ICE.
        if fn_has_unsatisfiable_preds(cx, def_id.to_def_id()) {
            return;
        }

        let mir = cx.tcx.optimized_mir(def_id.to_def_id());

        let maybe_storage_live_result = MaybeStorageLive
            .into_engine(cx.tcx, mir, def_id.to_def_id())
            .pass_name("redundant_clone")
            .iterate_to_fixpoint()
            .into_results_cursor(mir);
        let mut possible_borrower = {
            let mut vis = PossibleBorrowerVisitor::new(cx, mir);
            vis.visit_body(&mir);
            vis.into_map(cx, maybe_storage_live_result)
        };

        for (bb, bbdata) in mir.basic_blocks().iter_enumerated() {
            let terminator = bbdata.terminator();

            if terminator.source_info.span.from_expansion() {
                continue;
            }

            // Give up on loops
            if terminator.successors().any(|s| *s == bb) {
                continue;
            }

            let (fn_def_id, arg, arg_ty, clone_ret) =
                unwrap_or_continue!(is_call_with_ref_arg(cx, mir, &terminator.kind));

            let from_borrow = match_def_path(cx, fn_def_id, &paths::CLONE_TRAIT_METHOD)
                || match_def_path(cx, fn_def_id, &paths::TO_OWNED_METHOD)
                || (match_def_path(cx, fn_def_id, &paths::TO_STRING_METHOD)
                    && is_type_diagnostic_item(cx, arg_ty, sym!(string_type)));

            let from_deref = !from_borrow
                && (match_def_path(cx, fn_def_id, &paths::PATH_TO_PATH_BUF)
                    || match_def_path(cx, fn_def_id, &paths::OS_STR_TO_OS_STRING));
{'fraction_non_alphanumeric': 0.14506387921022068, 'fraction_numerical': 0.0005807200929152149, 'mean_word_length': 2.5509278350515463, 'pattern_counts': {'":': 0, '<': 15, '<?xml version=': 0, '>': 25, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
{'dir': 'git-commits-cleaned', 'id': '6941481', 'n_tokens_mistral': 2920, 'n_tokens_neox': 2882, 'n_words': 575}