[gcc r14-7345] gccrs: typecheck: Add basic typechecking for ReferenceType

[Arthur Cohen]

https://gcc.gnu.org/g:5104a38ae8563f011934452dee7f7aa3c89967ea

commit r14-7345-g5104a38ae8563f011934452dee7f7aa3c89967ea
Author: goar5670 <mahadelr19@gmail.com>
Date:   Tue Mar 7 01:25:39 2023 +0300

    gccrs: typecheck: Add basic typechecking for ReferenceType
    
    gcc/rust/ChangeLog:
            * hir/tree/rust-hir-pattern.h (HIR::ReferencePattern):
            added get_referenced_pattern function.
            * resolve/rust-ast-resolve-pattern.h
            (Resolve::PatternDeclaration): add visit function for
            AST::ReferencePattern
            * typecheck/rust-hir-type-check-pattern.cc
            (Resolver::TypeCheckPattern): add visit function for
            HIR::ReferencePattern
    
    gcc/testsuite/ChangeLog:
            * rust/compile/ref_pattern_fn_param.rs: New test.
    
    Signed-off-by: Mahmoud Mohamed <mahadelr19@gmail.com>

Diff:
---
 gcc/rust/hir/tree/rust-hir-pattern.h               | 6 ++++++
 gcc/rust/resolve/rust-ast-resolve-pattern.h        | 5 +++++
 gcc/rust/typecheck/rust-hir-type-check-pattern.cc  | 9 +++++++--
 gcc/testsuite/rust/compile/ref_pattern_fn_param.rs | 1 +
 4 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/gcc/rust/hir/tree/rust-hir-pattern.h b/gcc/rust/hir/tree/rust-hir-pattern.h
index 5826c8b3ee6..17921cc0391 100644
--- a/gcc/rust/hir/tree/rust-hir-pattern.h
+++ b/gcc/rust/hir/tree/rust-hir-pattern.h
@@ -477,6 +477,12 @@ public:
     return PatternType::REFERENCE;
   }
 
+  std::unique_ptr<Pattern> &get_referenced_pattern ()
+  {
+    rust_assert (pattern != nullptr);
+    return pattern;
+  }
+
 protected:
   /* Use covariance to implement clone function as returning this object rather
    * than base */
diff --git a/gcc/rust/resolve/rust-ast-resolve-pattern.h b/gcc/rust/resolve/rust-ast-resolve-pattern.h
index d8de1792005..0811a031386 100644
--- a/gcc/rust/resolve/rust-ast-resolve-pattern.h
+++ b/gcc/rust/resolve/rust-ast-resolve-pattern.h
@@ -75,6 +75,11 @@ public:
     pattern.get_pattern_in_parens ()->accept_vis (*this);
   }
 
+  void visit (AST::ReferencePattern &pattern) override
+  {
+    pattern.get_referenced_pattern ()->accept_vis (*this);
+  }
+
   // cases in a match expression
   void visit (AST::PathInExpression &pattern) override;
 
diff --git a/gcc/rust/typecheck/rust-hir-type-check-pattern.cc b/gcc/rust/typecheck/rust-hir-type-check-pattern.cc
index f5ac7baf51e..b277a5630fc 100644
--- a/gcc/rust/typecheck/rust-hir-type-check-pattern.cc
+++ b/gcc/rust/typecheck/rust-hir-type-check-pattern.cc
@@ -410,8 +410,13 @@ TypeCheckPattern::visit (HIR::QualifiedPathInExpression &pattern)
 void
 TypeCheckPattern::visit (HIR::ReferencePattern &pattern)
 {
-  rust_sorry_at (pattern.get_locus (),
-		 "type checking qualified path patterns not supported");
+  if (parent->get_kind () != TyTy::TypeKind::REF)
+    rust_error_at (pattern.get_locus (), "expected %s, found reference",
+		   parent->as_string ().c_str ());
+
+  TyTy::ReferenceType *ref_ty_ty = static_cast<TyTy::ReferenceType *> (parent);
+  TypeCheckPattern::Resolve (pattern.get_referenced_pattern ().get (),
+			     ref_ty_ty->get_base ());
 }
 
 void
diff --git a/gcc/testsuite/rust/compile/ref_pattern_fn_param.rs b/gcc/testsuite/rust/compile/ref_pattern_fn_param.rs
new file mode 100644
index 00000000000..67ea033a2b2
--- /dev/null
+++ b/gcc/testsuite/rust/compile/ref_pattern_fn_param.rs
@@ -0,0 +1 @@
+fn f(&b: i32) {} // { dg-error "expected i32, found reference" }