converter: Move literal conversion out

The literal conversion code could be used for the literal_from_string
callback, this means we should move it out of the function in it's own
function. This involves a new switch, which is quite sad but we're not
yet at a performance profiling phase, there may be lower hanging fruits.

gcc/rust/ChangeLog:

	* util/rust-token-converter.cc (handle_suffix): Rework function
	to make it work with the new literal conversion function.
	(convert_literal): Add a new function to convert to a proc macro
	literal from a literal tokenptr. The function will abort if the
	pointer does not point to a literal.
	(convert): Add call to convert literal for every literal case.
	* util/rust-token-converter.h (convert_literal): Add public
	prototype.

Signed-off-by: Pierre-Emmanuel Patry <pierre-emmanuel.patry@embecosm.com>

2 files changed, 36 insertions, 27 deletions

diff --git a/gcc/rust/util/rust-token-converter.cc b/gcc/rust/util/rust-token-converter.cc
index 67c1459..e0794f38 100644
--- a/gcc/rust/util/rust-token-converter.cc
+++ b/gcc/rust/util/rust-token-converter.cc
@@ -63,16 +63,41 @@ convert (ProcMacro::Span span)
   return span.start;
 }
 
-static void
-handle_suffix (ProcMacro::TokenStream &ts, const const_TokenPtr &token,
-	       ProcMacro::LitKind kind)
+static ProcMacro::Literal
+handle_suffix (const const_TokenPtr &token, ProcMacro::LitKind kind)
 {
   auto str = token->as_string ();
   auto lookup = suffixes.lookup (token->get_type_hint ());
   auto suffix = suffixes.is_iter_ok (lookup) ? lookup->second : "";
-  ts.push (ProcMacro::TokenTree::make_tokentree (
-    ProcMacro::Literal::make_literal (kind, convert (token->get_locus ()), str,
-				      suffix)));
+  return ProcMacro::Literal::make_literal (kind, convert (token->get_locus ()),
+					   str, suffix);
+}
+
+ProcMacro::Literal
+convert_literal (const_TokenPtr lit)
+{
+  auto loc = convert (lit->get_locus ());
+  switch (lit->get_id ())
+    {
+    case FLOAT_LITERAL:
+      return handle_suffix (lit, ProcMacro::LitKind::make_float ());
+    case INT_LITERAL:
+      return handle_suffix (lit, ProcMacro::LitKind::make_integer ());
+    case CHAR_LITERAL:
+      return ProcMacro::Literal::make_literal (ProcMacro::LitKind::make_char (),
+					       loc, lit->as_string ());
+    case STRING_LITERAL:
+      return ProcMacro::Literal::make_literal (ProcMacro::LitKind::make_str (),
+					       loc, lit->as_string ());
+    case BYTE_CHAR_LITERAL:
+      return ProcMacro::Literal::make_literal (ProcMacro::LitKind::make_byte (),
+					       loc, lit->as_string ());
+    case BYTE_STRING_LITERAL:
+      return ProcMacro::Literal::make_literal (
+	ProcMacro::LitKind::make_byte_str (), loc, lit->as_string ());
+    default:
+      rust_unreachable ();
+    }
 }
 
 ProcMacro::TokenStream
@@ -87,32 +112,13 @@ convert (const std::vector<const_TokenPtr> &tokens)
 	{
 	// Literals
 	case FLOAT_LITERAL:
-	  handle_suffix (trees.back (), token,
-			 ProcMacro::LitKind::make_float ());
-	  break;
 	case INT_LITERAL:
-	  handle_suffix (trees.back (), token,
-			 ProcMacro::LitKind::make_integer ());
-	  break;
 	case CHAR_LITERAL:
-	  trees.back ().push (ProcMacro::TokenTree::make_tokentree (
-	    ProcMacro::Literal::make_literal (ProcMacro::LitKind::make_char (),
-					      loc, token->as_string ())));
-	  break;
 	case STRING_LITERAL:
-	  trees.back ().push (ProcMacro::TokenTree::make_tokentree (
-	    ProcMacro::Literal::make_literal (ProcMacro::LitKind::make_str (),
-					      loc, token->as_string ())));
-	  break;
 	case BYTE_CHAR_LITERAL:
-	  trees.back ().push (ProcMacro::TokenTree::make_tokentree (
-	    ProcMacro::Literal::make_literal (ProcMacro::LitKind::make_byte (),
-					      loc, token->as_string ())));
-	  break;
 	case BYTE_STRING_LITERAL:
-	  trees.back ().push (ProcMacro::TokenTree::make_tokentree (
-	    ProcMacro::Literal::make_literal (
-	      ProcMacro::LitKind::make_byte_str (), loc, token->as_string ())));
+	  trees.back ().push (
+	    ProcMacro::TokenTree::make_tokentree (convert_literal (token)));
 	  break;
 	// Ident
 	case IDENTIFIER:
diff --git a/gcc/rust/util/rust-token-converter.h b/gcc/rust/util/rust-token-converter.h
index 75b3b38..3e9feeb 100644
--- a/gcc/rust/util/rust-token-converter.h
+++ b/gcc/rust/util/rust-token-converter.h
@@ -29,6 +29,9 @@ convert (const std::vector<const_TokenPtr> &tokens);
 std::vector<const_TokenPtr>
 convert (const ProcMacro::TokenStream &ts);
 
+ProcMacro::Literal
+convert_literal (const_TokenPtr lit);
+
 } // namespace Rust
 
 #endif /* ! RUST_TOKEN_CONVERTER_H */