[gcc r16-2845] gccrs: Support compilation of IdentifierPattern's subpatterns

[Arthur Cohen via Gcc-cvs]

https://gcc.gnu.org/g:0613241c5e841527753f09038956e38956320d35

commit r16-2845-g0613241c5e841527753f09038956e38956320d35
Author: Zhi Heng <yapz...@gmail.com>
Date:   Sat Jun 7 22:24:03 2025 +0800

    gccrs: Support compilation of IdentifierPattern's subpatterns
    
    gcc/rust/ChangeLog:
    
            * backend/rust-compile-pattern.cc: Add CheckExpr compilation for
                    IdentifierPattern with subpattern.
            * backend/rust-compile-pattern.h: Modify IdentifierPattern's
                    visit func to support the above.
            * typecheck/rust-hir-type-check-pattern.cc: Add typechecking
                    support for the changes above.
    
    Signed-off-by: Yap Zhi Heng <yapz...@gmail.com>

Diff:
---
 gcc/rust/backend/rust-compile-pattern.cc                      | 11 +++++++++++
 gcc/rust/backend/rust-compile-pattern.h                       |  5 +----
 gcc/rust/typecheck/rust-hir-type-check-pattern.cc             |  5 +++++
 gcc/testsuite/rust/compile/match-identifierpattern.rs         |  9 +++++++++
 gcc/testsuite/rust/execute/torture/match-identifierpattern.rs | 10 ++++++++++
 5 files changed, 36 insertions(+), 4 deletions(-)

diff --git a/gcc/rust/backend/rust-compile-pattern.cc 
b/gcc/rust/backend/rust-compile-pattern.cc
index 7b937c766e2a..f81e910b2b2d 100644
--- a/gcc/rust/backend/rust-compile-pattern.cc
+++ b/gcc/rust/backend/rust-compile-pattern.cc
@@ -434,6 +434,17 @@ CompilePatternCheckExpr::visit (HIR::TuplePattern &pattern)
     }
 }
 
+void CompilePatternCheckExpr::visit (HIR::IdentifierPattern &pattern)
+{
+  if (pattern.has_pattern_to_bind())
+  {
+    check_expr = CompilePatternCheckExpr::Compile (pattern.get_to_bind(), 
match_scrutinee_expr, ctx);
+  } else
+  {
+    check_expr = boolean_true_node;
+  }
+}
+
 // setup the bindings
 
 void
diff --git a/gcc/rust/backend/rust-compile-pattern.h 
b/gcc/rust/backend/rust-compile-pattern.h
index 85c82b8458f8..4dd7d559e6eb 100644
--- a/gcc/rust/backend/rust-compile-pattern.h
+++ b/gcc/rust/backend/rust-compile-pattern.h
@@ -45,12 +45,9 @@ public:
   void visit (HIR::StructPattern &) override;
   void visit (HIR::TupleStructPattern &) override;
   void visit (HIR::TuplePattern &) override;
+  void visit (HIR::IdentifierPattern &) override;
 
   // Always succeeds
-  void visit (HIR::IdentifierPattern &) override
-  {
-    check_expr = boolean_true_node;
-  }
   void visit (HIR::WildcardPattern &) override
   {
     check_expr = boolean_true_node;
diff --git a/gcc/rust/typecheck/rust-hir-type-check-pattern.cc 
b/gcc/rust/typecheck/rust-hir-type-check-pattern.cc
index 102083bd84c3..c1037ecd54e8 100644
--- a/gcc/rust/typecheck/rust-hir-type-check-pattern.cc
+++ b/gcc/rust/typecheck/rust-hir-type-check-pattern.cc
@@ -546,6 +546,11 @@ TypeCheckPattern::visit (HIR::RangePattern &pattern)
 void
 TypeCheckPattern::visit (HIR::IdentifierPattern &pattern)
 {
+  if (pattern.has_pattern_to_bind ())
+    {
+      TypeCheckPattern::Resolve (pattern.get_to_bind (), parent);
+    }
+
   if (!pattern.get_is_ref ())
     {
       infered = parent;
diff --git a/gcc/testsuite/rust/compile/match-identifierpattern.rs 
b/gcc/testsuite/rust/compile/match-identifierpattern.rs
new file mode 100644
index 000000000000..6c558ac065b9
--- /dev/null
+++ b/gcc/testsuite/rust/compile/match-identifierpattern.rs
@@ -0,0 +1,9 @@
+fn main() {
+    let x = 1;
+
+    match x {
+        2 => {},
+        a @ 3 => {},
+        _ => {},
+    }
+}
diff --git a/gcc/testsuite/rust/execute/torture/match-identifierpattern.rs 
b/gcc/testsuite/rust/execute/torture/match-identifierpattern.rs
new file mode 100644
index 000000000000..b102ad1ec417
--- /dev/null
+++ b/gcc/testsuite/rust/execute/torture/match-identifierpattern.rs
@@ -0,0 +1,10 @@
+fn main() -> i32 {
+    let mut x = 2;
+
+    match x {
+        a @ 2 => { x = a + 1 },
+        _ => {}
+    }
+
+    x - 3
+}