Add AltPattern HIR node

Example:
	match x {
	    0 | 1 => true,
	    _ => false
	}

gcc/rust/ChangeLog:

	* backend/rust-compile-fnparam.h:
	(CompileFnParam::visit): Add AltPattern visitor.
	* backend/rust-compile-pattern.h:
	(CompilePatternCaseLabelExpr::visit): Add AltPattern visitor.
	(CompilePatternBindings::visit): Add AltPattern visitor.
	(CompilePatternLet::visit): Add AltPattern visitor.
	* backend/rust-compile-resolve-path.h:
	(ResolvePathRef::visit): Add AltPattern visitor.
	* backend/rust-compile-var-decl.h:
	(CompileVarDecl::visit): Add AltPattern visitor.
	* checks/errors/rust-const-checker.cc
	(ConstChecker::visit): Add AltPattern visitor.
	* checks/errors/rust-const-checker.h:
	(ConstChecker::visit): Add AltPattern visitor.
	* checks/errors/rust-unsafe-checker.cc
	(UnsafeChecker::visit): Add AltPattern visitor.
	* checks/errors/rust-unsafe-checker.h:
	(UnsafeChecker::visit): Add AltPattern visitor.
	* hir/rust-hir-dump.cc
	(Dump::visit): Add AltPattern visitor.
	* hir/rust-hir-dump.h:
	(Dump::visit): Add AltPattern visitor.
	* hir/tree/rust-hir-full-decls.h
	(class AltPattern): Add forward declaration.
	* hir/tree/rust-hir-pattern.h
	(class AltPattern): New class.
	* hir/tree/rust-hir-visitor.h:
	(HIRFullVisitor::visit): Add AltPattern visitor.
	(HIRFullVisitorBase::visit): Add AltPattern visitor.
	(HIRPatternVisitor::visit): Add AltPattern visitor.
	* hir/tree/rust-hir.h:
	(Pattern::PatternType::ALT): New enumerator.
	* typecheck/rust-hir-type-check-pattern.cc
	(TypeCheckPattern::visit): Add AltPattern visitor.
	* typecheck/rust-hir-type-check-pattern.h:
	(TypeCheckPattern::visit): Add AltPattern visitor.

Signed-off-by: Owen Avery <powerboat9.gamer@gmail.com>

4 files changed, 23 insertions, 0 deletions

diff --git a/gcc/rust/backend/rust-compile-fnparam.h b/gcc/rust/backend/rust-compile-fnparam.h
index 10e8b67..c5b08e3a 100644
--- a/gcc/rust/backend/rust-compile-fnparam.h
+++ b/gcc/rust/backend/rust-compile-fnparam.h
@@ -39,6 +39,7 @@ public:
   void visit (HIR::TupleStructPattern &) override;
 
   // Empty visit for unused Pattern HIR nodes.
+  void visit (HIR::AltPattern &) override {}
   void visit (HIR::LiteralPattern &) override {}
   void visit (HIR::PathInExpression &) override {}
   void visit (HIR::QualifiedPathInExpression &) override {}
diff --git a/gcc/rust/backend/rust-compile-pattern.h b/gcc/rust/backend/rust-compile-pattern.h
index 8f44b7b..93faeeae 100644
--- a/gcc/rust/backend/rust-compile-pattern.h
+++ b/gcc/rust/backend/rust-compile-pattern.h
@@ -39,6 +39,13 @@ public:
   void visit (HIR::WildcardPattern &pattern) override;
   void visit (HIR::RangePattern &pattern) override;
 
+  // unsupported
+  void visit (HIR::AltPattern &pattern) override
+  {
+    rust_sorry_at (pattern.get_locus (),
+		   "alternate pattern case labels not supported");
+  }
+
   // Empty visit for unused Pattern HIR nodes.
   void visit (HIR::IdentifierPattern &) override {}
   void visit (HIR::LiteralPattern &) override;
@@ -70,6 +77,13 @@ public:
   void visit (HIR::StructPattern &pattern) override;
   void visit (HIR::TupleStructPattern &pattern) override;
 
+  // unsupported
+  void visit (HIR::AltPattern &pattern) override
+  {
+    rust_sorry_at (pattern.get_locus (),
+		   "alternate pattern bindings not supported");
+  }
+
   // Empty visit for unused Pattern HIR nodes.
   void visit (HIR::IdentifierPattern &) override {}
   void visit (HIR::LiteralPattern &) override {}
@@ -104,6 +118,12 @@ public:
   void visit (HIR::TuplePattern &) override;
 
   // check for unimplemented Pattern HIR nodes.
+  void visit (HIR::AltPattern &pattern) override
+  {
+    rust_sorry_at (pattern.get_locus (),
+		   "alternate pattern let statements not supported");
+  }
+
   void visit (HIR::LiteralPattern &pattern) override
   {
     rust_sorry_at (pattern.get_locus (),
diff --git a/gcc/rust/backend/rust-compile-resolve-path.h b/gcc/rust/backend/rust-compile-resolve-path.h
index 6aec7be..ad7a67f 100644
--- a/gcc/rust/backend/rust-compile-resolve-path.h
+++ b/gcc/rust/backend/rust-compile-resolve-path.h
@@ -50,6 +50,7 @@ public:
   void visit (HIR::RangePattern &) override {}
   void visit (HIR::ReferencePattern &) override {}
   void visit (HIR::SlicePattern &) override {}
+  void visit (HIR::AltPattern &) override {}
   void visit (HIR::StructPattern &) override {}
   void visit (HIR::TuplePattern &) override {}
   void visit (HIR::TupleStructPattern &) override {}
diff --git a/gcc/rust/backend/rust-compile-var-decl.h b/gcc/rust/backend/rust-compile-var-decl.h
index 13b429d..bc83816 100644
--- a/gcc/rust/backend/rust-compile-var-decl.h
+++ b/gcc/rust/backend/rust-compile-var-decl.h
@@ -54,6 +54,7 @@ public:
   }
 
   // Empty visit for unused Pattern HIR nodes.
+  void visit (HIR::AltPattern &) override {}
   void visit (HIR::LiteralPattern &) override {}
   void visit (HIR::PathInExpression &) override {}
   void visit (HIR::QualifiedPathInExpression &) override {}