Adding upstream version 1.64.0+dfsg1.upstream/1.64.0+dfsg1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 244 insertions, 0 deletions

diff --git a/compiler/rustc_middle/src/thir/visit.rs b/compiler/rustc_middle/src/thir/visit.rs
new file mode 100644
index 000000000..97249fdd1
--- /dev/null
+++ b/compiler/rustc_middle/src/thir/visit.rs
@@ -0,0 +1,244 @@
+use super::{
+    Arm, Block, Expr, ExprKind, Guard, InlineAsmOperand, Pat, PatKind, Stmt, StmtKind, Thir,
+};
+
+pub trait Visitor<'a, 'tcx: 'a>: Sized {
+    fn thir(&self) -> &'a Thir<'tcx>;
+
+    fn visit_expr(&mut self, expr: &Expr<'tcx>) {
+        walk_expr(self, expr);
+    }
+
+    fn visit_stmt(&mut self, stmt: &Stmt<'tcx>) {
+        walk_stmt(self, stmt);
+    }
+
+    fn visit_block(&mut self, block: &Block) {
+        walk_block(self, block);
+    }
+
+    fn visit_arm(&mut self, arm: &Arm<'tcx>) {
+        walk_arm(self, arm);
+    }
+
+    fn visit_pat(&mut self, pat: &Pat<'tcx>) {
+        walk_pat(self, pat);
+    }
+
+    // Note: We don't have visitors for `ty::Const` and `mir::ConstantKind`
+    // (even though these types occur in THIR) for consistency and to reduce confusion,
+    // since the lazy creation of constants during thir construction causes most
+    // 'constants' to not be of type `ty::Const` or `mir::ConstantKind` at that
+    // stage (they are mostly still identified by `DefId` or `hir::Lit`, see
+    // the variants `Literal`, `NonHirLiteral` and `NamedConst` in `thir::ExprKind`).
+    // You have to manually visit `ty::Const` and `mir::ConstantKind` through the
+    // other `visit*` functions.
+}
+
+pub fn walk_expr<'a, 'tcx: 'a, V: Visitor<'a, 'tcx>>(visitor: &mut V, expr: &Expr<'tcx>) {
+    use ExprKind::*;
+    match expr.kind {
+        Scope { value, region_scope: _, lint_level: _ } => {
+            visitor.visit_expr(&visitor.thir()[value])
+        }
+        Box { value } => visitor.visit_expr(&visitor.thir()[value]),
+        If { cond, then, else_opt, if_then_scope: _ } => {
+            visitor.visit_expr(&visitor.thir()[cond]);
+            visitor.visit_expr(&visitor.thir()[then]);
+            if let Some(else_expr) = else_opt {
+                visitor.visit_expr(&visitor.thir()[else_expr]);
+            }
+        }
+        Call { fun, ref args, ty: _, from_hir_call: _, fn_span: _ } => {
+            visitor.visit_expr(&visitor.thir()[fun]);
+            for &arg in &**args {
+                visitor.visit_expr(&visitor.thir()[arg]);
+            }
+        }
+        Deref { arg } => visitor.visit_expr(&visitor.thir()[arg]),
+        Binary { lhs, rhs, op: _ } | LogicalOp { lhs, rhs, op: _ } => {
+            visitor.visit_expr(&visitor.thir()[lhs]);
+            visitor.visit_expr(&visitor.thir()[rhs]);
+        }
+        Unary { arg, op: _ } => visitor.visit_expr(&visitor.thir()[arg]),
+        Cast { source } => visitor.visit_expr(&visitor.thir()[source]),
+        Use { source } => visitor.visit_expr(&visitor.thir()[source]),
+        NeverToAny { source } => visitor.visit_expr(&visitor.thir()[source]),
+        Pointer { source, cast: _ } => visitor.visit_expr(&visitor.thir()[source]),
+        Let { expr, .. } => {
+            visitor.visit_expr(&visitor.thir()[expr]);
+        }
+        Loop { body } => visitor.visit_expr(&visitor.thir()[body]),
+        Match { scrutinee, ref arms } => {
+            visitor.visit_expr(&visitor.thir()[scrutinee]);
+            for &arm in &**arms {
+                visitor.visit_arm(&visitor.thir()[arm]);
+            }
+        }
+        Block { ref body } => visitor.visit_block(body),
+        Assign { lhs, rhs } | AssignOp { lhs, rhs, op: _ } => {
+            visitor.visit_expr(&visitor.thir()[lhs]);
+            visitor.visit_expr(&visitor.thir()[rhs]);
+        }
+        Field { lhs, variant_index: _, name: _ } => visitor.visit_expr(&visitor.thir()[lhs]),
+        Index { lhs, index } => {
+            visitor.visit_expr(&visitor.thir()[lhs]);
+            visitor.visit_expr(&visitor.thir()[index]);
+        }
+        VarRef { id: _ } | UpvarRef { closure_def_id: _, var_hir_id: _ } => {}
+        Borrow { arg, borrow_kind: _ } => visitor.visit_expr(&visitor.thir()[arg]),
+        AddressOf { arg, mutability: _ } => visitor.visit_expr(&visitor.thir()[arg]),
+        Break { value, label: _ } => {
+            if let Some(value) = value {
+                visitor.visit_expr(&visitor.thir()[value])
+            }
+        }
+        Continue { label: _ } => {}
+        Return { value } => {
+            if let Some(value) = value {
+                visitor.visit_expr(&visitor.thir()[value])
+            }
+        }
+        ConstBlock { did: _, substs: _ } => {}
+        Repeat { value, count: _ } => {
+            visitor.visit_expr(&visitor.thir()[value]);
+        }
+        Array { ref fields } | Tuple { ref fields } => {
+            for &field in &**fields {
+                visitor.visit_expr(&visitor.thir()[field]);
+            }
+        }
+        Adt(box crate::thir::Adt {
+            ref fields,
+            ref base,
+            adt_def: _,
+            variant_index: _,
+            substs: _,
+            user_ty: _,
+        }) => {
+            for field in &**fields {
+                visitor.visit_expr(&visitor.thir()[field.expr]);
+            }
+            if let Some(base) = base {
+                visitor.visit_expr(&visitor.thir()[base.base]);
+            }
+        }
+        PlaceTypeAscription { source, user_ty: _ } | ValueTypeAscription { source, user_ty: _ } => {
+            visitor.visit_expr(&visitor.thir()[source])
+        }
+        Closure { closure_id: _, substs: _, upvars: _, movability: _, fake_reads: _ } => {}
+        Literal { lit: _, neg: _ } => {}
+        NonHirLiteral { lit: _, user_ty: _ } => {}
+        ZstLiteral { user_ty: _ } => {}
+        NamedConst { def_id: _, substs: _, user_ty: _ } => {}
+        ConstParam { param: _, def_id: _ } => {}
+        StaticRef { alloc_id: _, ty: _, def_id: _ } => {}
+        InlineAsm { ref operands, template: _, options: _, line_spans: _ } => {
+            for op in &**operands {
+                use InlineAsmOperand::*;
+                match op {
+                    In { expr, reg: _ }
+                    | Out { expr: Some(expr), reg: _, late: _ }
+                    | InOut { expr, reg: _, late: _ } => visitor.visit_expr(&visitor.thir()[*expr]),
+                    SplitInOut { in_expr, out_expr, reg: _, late: _ } => {
+                        visitor.visit_expr(&visitor.thir()[*in_expr]);
+                        if let Some(out_expr) = out_expr {
+                            visitor.visit_expr(&visitor.thir()[*out_expr]);
+                        }
+                    }
+                    Out { expr: None, reg: _, late: _ }
+                    | Const { value: _, span: _ }
+                    | SymFn { value: _, span: _ }
+                    | SymStatic { def_id: _ } => {}
+                }
+            }
+        }
+        ThreadLocalRef(_) => {}
+        Yield { value } => visitor.visit_expr(&visitor.thir()[value]),
+    }
+}
+
+pub fn walk_stmt<'a, 'tcx: 'a, V: Visitor<'a, 'tcx>>(visitor: &mut V, stmt: &Stmt<'tcx>) {
+    match &stmt.kind {
+        StmtKind::Expr { expr, scope: _ } => visitor.visit_expr(&visitor.thir()[*expr]),
+        StmtKind::Let {
+            initializer,
+            remainder_scope: _,
+            init_scope: _,
+            ref pattern,
+            lint_level: _,
+            else_block,
+        } => {
+            if let Some(init) = initializer {
+                visitor.visit_expr(&visitor.thir()[*init]);
+            }
+            visitor.visit_pat(pattern);
+            if let Some(block) = else_block {
+                visitor.visit_block(block)
+            }
+        }
+    }
+}
+
+pub fn walk_block<'a, 'tcx: 'a, V: Visitor<'a, 'tcx>>(visitor: &mut V, block: &Block) {
+    for &stmt in &*block.stmts {
+        visitor.visit_stmt(&visitor.thir()[stmt]);
+    }
+    if let Some(expr) = block.expr {
+        visitor.visit_expr(&visitor.thir()[expr]);
+    }
+}
+
+pub fn walk_arm<'a, 'tcx: 'a, V: Visitor<'a, 'tcx>>(visitor: &mut V, arm: &Arm<'tcx>) {
+    match arm.guard {
+        Some(Guard::If(expr)) => visitor.visit_expr(&visitor.thir()[expr]),
+        Some(Guard::IfLet(ref pat, expr)) => {
+            visitor.visit_pat(pat);
+            visitor.visit_expr(&visitor.thir()[expr]);
+        }
+        None => {}
+    }
+    visitor.visit_pat(&arm.pattern);
+    visitor.visit_expr(&visitor.thir()[arm.body]);
+}
+
+pub fn walk_pat<'a, 'tcx: 'a, V: Visitor<'a, 'tcx>>(visitor: &mut V, pat: &Pat<'tcx>) {
+    use PatKind::*;
+    match pat.kind.as_ref() {
+        AscribeUserType { subpattern, ascription: _ }
+        | Deref { subpattern }
+        | Binding {
+            subpattern: Some(subpattern),
+            mutability: _,
+            mode: _,
+            var: _,
+            ty: _,
+            is_primary: _,
+            name: _,
+        } => visitor.visit_pat(&subpattern),
+        Binding { .. } | Wild => {}
+        Variant { subpatterns, adt_def: _, substs: _, variant_index: _ } | Leaf { subpatterns } => {
+            for subpattern in subpatterns {
+                visitor.visit_pat(&subpattern.pattern);
+            }
+        }
+        Constant { value: _ } => {}
+        Range(_) => {}
+        Slice { prefix, slice, suffix } | Array { prefix, slice, suffix } => {
+            for subpattern in prefix {
+                visitor.visit_pat(&subpattern);
+            }
+            if let Some(pat) = slice {
+                visitor.visit_pat(pat);
+            }
+            for subpattern in suffix {
+                visitor.visit_pat(&subpattern);
+            }
+        }
+        Or { pats } => {
+            for pat in pats {
+                visitor.visit_pat(&pat);
+            }
+        }
+    };
+}