[gcc r15-8810] gccrs: ast-builder: Improve function generation.

[Arthur Cohen via Gcc-cvs]

https://gcc.gnu.org/g:0897e2bcaf047cb52b65c151bd0cc7fe29b3279f

commit r15-8810-g0897e2bcaf047cb52b65c151bd0cc7fe29b3279f
Author: Arthur Cohen <arthur.co...@embecosm.com>
Date:   Thu Jan 30 14:56:37 2025 +0100

    gccrs: ast-builder: Improve function generation.
    
    gcc/rust/ChangeLog:
    
            * ast/rust-ast-builder.cc (Builder::block): Change return type.
            (Builder::loop): Use new APIs.
            * ast/rust-ast-builder.h: Change return type of block functions.

Diff:
---
 gcc/rust/ast/rust-ast-builder.cc | 22 +++++++++++-----------
 gcc/rust/ast/rust-ast-builder.h  | 12 ++++++------
 2 files changed, 17 insertions(+), 17 deletions(-)

diff --git a/gcc/rust/ast/rust-ast-builder.cc b/gcc/rust/ast/rust-ast-builder.cc
index 369f5a44630b..f59ff19d6215 100644
--- a/gcc/rust/ast/rust-ast-builder.cc
+++ b/gcc/rust/ast/rust-ast-builder.cc
@@ -279,23 +279,25 @@ Builder::path_in_expression (LangItem::Kind lang_item) 
const
   return PathInExpression (lang_item, {}, loc);
 }
 
-std::unique_ptr<Expr>
-Builder::block (std::unique_ptr<Stmt> &&stmt,
+std::unique_ptr<BlockExpr>
+Builder::block (tl::optional<std::unique_ptr<Stmt>> &&stmt,
                std::unique_ptr<Expr> &&tail_expr) const
 {
   auto stmts = std::vector<std::unique_ptr<Stmt>> ();
-  stmts.emplace_back (std::move (stmt));
+
+  if (stmt)
+    stmts.emplace_back (std::move (*stmt));
 
   return block (std::move (stmts), std::move (tail_expr));
 }
 
-std::unique_ptr<Expr>
+std::unique_ptr<BlockExpr>
 Builder::block (std::vector<std::unique_ptr<Stmt>> &&stmts,
                std::unique_ptr<Expr> &&tail_expr) const
 {
-  return std::unique_ptr<Expr> (new BlockExpr (std::move (stmts),
-                                              std::move (tail_expr), {}, {},
-                                              LoopLabel::error (), loc, loc));
+  return std::unique_ptr<BlockExpr> (
+    new BlockExpr (std::move (stmts), std::move (tail_expr), {}, {},
+                  LoopLabel::error (), loc, loc));
 }
 
 std::unique_ptr<Expr>
@@ -421,11 +423,9 @@ Builder::match_case (std::unique_ptr<Pattern> &&pattern,
 std::unique_ptr<Expr>
 Builder::loop (std::vector<std::unique_ptr<Stmt>> &&stmts)
 {
-  auto block = std::unique_ptr<BlockExpr> (
-    new BlockExpr (std::move (stmts), nullptr, {}, {}, LoopLabel::error (), 
loc,
-                  loc));
+  auto block_expr = block (std::move (stmts), nullptr);
 
-  return std::unique_ptr<Expr> (new LoopExpr (std::move (block), loc));
+  return std::unique_ptr<Expr> (new LoopExpr (std::move (block_expr), loc));
 }
 
 std::unique_ptr<TypeParamBound>
diff --git a/gcc/rust/ast/rust-ast-builder.h b/gcc/rust/ast/rust-ast-builder.h
index 99ab1610ce7a..9fbcea182be6 100644
--- a/gcc/rust/ast/rust-ast-builder.h
+++ b/gcc/rust/ast/rust-ast-builder.h
@@ -82,12 +82,12 @@ public:
   std::unique_ptr<Expr> deref (std::unique_ptr<Expr> &&of) const;
 
   /* Create a block with an optional tail expression */
-  std::unique_ptr<Expr> block (std::vector<std::unique_ptr<Stmt>> &&stmts,
-                              std::unique_ptr<Expr> &&tail_expr
-                              = nullptr) const;
-  std::unique_ptr<Expr> block (std::unique_ptr<Stmt> &&stmt,
-                              std::unique_ptr<Expr> &&tail_expr
-                              = nullptr) const;
+  std::unique_ptr<BlockExpr> block (std::vector<std::unique_ptr<Stmt>> &&stmts,
+                                   std::unique_ptr<Expr> &&tail_expr
+                                   = nullptr) const;
+  std::unique_ptr<BlockExpr> block (tl::optional<std::unique_ptr<Stmt>> &&stmt,
+                                   std::unique_ptr<Expr> &&tail_expr
+                                   = nullptr) const;
 
   /* Create an early return expression with an optional expression */
   std::unique_ptr<Expr> return_expr (std::unique_ptr<Expr> &&to_return