[gcc r14-8555] gccrs: Introduce a proper keyword list

[gcc r14-8555] gccrs: Introduce a proper keyword list

[Arthur Cohen]

https://gcc.gnu.org/g:2c843a047dd3c596b4daabe247e52e1d6475e4d6

commit r14-8555-g2c843a047dd3c596b4daabe247e52e1d6475e4d6
Author: Pierre-Emmanuel Patry <pierre-emmanuel.patry@embecosm.com>
Date:   Thu Nov 16 16:20:49 2023 +0100

    gccrs: Introduce a proper keyword list
    
    The old "keyword" list was used for the lexer, and could therefore not
    be used with keyword spanning over multiple tokens as those tokens should
    remain lexed as is. Hence the introduction of a new list macro for
    keyword exclusive tasks. This also means we can no longer match a token
    id for each keyword. The token id map has been renamed to keep it's
    properties.
    
    gcc/rust/ChangeLog:
    
            * lex/rust-lex.cc (Lexer::classify_keyword): Update keyword map name.
            * lex/rust-token.h (enum PrimitiveCoreType): Remove some deprecated
            comments.
            * util/rust-keyword-values.cc (get_keywords): Update the keyword map
            name.
            (RS_TOKEN): Define as empty
            (RS_TOKEN_KEYWORD_2015): Add the emission value.
            (RS_TOKEN_KEYWORD_2018): Likewise.
            * util/rust-keyword-values.h (RS_KEYWORD_LIST): Introduce the keyword
            list.
            (RS_TOKEN_KEYWORD_2018): Define multiple new keywords.
    
    Signed-off-by: Pierre-Emmanuel Patry <pierre-emmanuel.patry@embecosm.com>

Diff:
---
 gcc/rust/lex/rust-lex.cc             |  2 +-
 gcc/rust/lex/rust-token.h            |  2 --
 gcc/rust/util/rust-keyword-values.cc | 13 ++++++++++++-
 gcc/rust/util/rust-keyword-values.h  | 13 +++++++++++--
 4 files changed, 24 insertions(+), 6 deletions(-)

diff --git a/gcc/rust/lex/rust-lex.cc b/gcc/rust/lex/rust-lex.cc
index 2d41c114f73e..5bff2d9125c4 100644
--- a/gcc/rust/lex/rust-lex.cc
+++ b/gcc/rust/lex/rust-lex.cc
@@ -260,7 +260,7 @@ Lexer::replace_current_token (TokenPtr replacement)
 TokenId
 Lexer::classify_keyword (const std::string &str)
 {
-  auto &keywords = Rust::Values::Keywords::keywords;
+  auto &keywords = Rust::Values::Keywords::keywords_tokens;
   auto keyword = keywords.find (str);
 
   if (keyword == keywords.end ())
diff --git a/gcc/rust/lex/rust-token.h b/gcc/rust/lex/rust-token.h
index e38c3cf99433..438b29b49572 100644
--- a/gcc/rust/lex/rust-token.h
+++ b/gcc/rust/lex/rust-token.h
@@ -145,7 +145,6 @@ enum PrimitiveCoreType
   /* Doc Comments */                                                           \
   RS_TOKEN (INNER_DOC_COMMENT, "#![doc]")                                      \
   RS_TOKEN (OUTER_DOC_COMMENT, "#[doc]")                                       \
-  /* have "weak" union and 'static keywords? */                                \
   RS_TOKEN_KEYWORD_2015 (ABSTRACT, "abstract") /* unused */                    \
   RS_TOKEN_KEYWORD_2015 (AS, "as")                                             \
   RS_TOKEN_KEYWORD_2018 (ASYNC, "async") /* unused */                          \
@@ -157,7 +156,6 @@ enum PrimitiveCoreType
   RS_TOKEN_KEYWORD_2015 (CONST, "const")                                       \
   RS_TOKEN_KEYWORD_2015 (CONTINUE, "continue")                                 \
   RS_TOKEN_KEYWORD_2015 (CRATE, "crate")                                       \
-  /* FIXME: Do we need to add $crate (DOLLAR_CRATE) as a reserved kw? */       \
   RS_TOKEN_KEYWORD_2015 (DO, "do") /* unused */                                \
   RS_TOKEN_KEYWORD_2018 (DYN, "dyn")                                           \
   RS_TOKEN_KEYWORD_2015 (ELSE, "else")                                         \
diff --git a/gcc/rust/util/rust-keyword-values.cc b/gcc/rust/util/rust-keyword-values.cc
index 8aa5ef1371ab..9e1d2bcdef6b 100644
--- a/gcc/rust/util/rust-keyword-values.cc
+++ b/gcc/rust/util/rust-keyword-values.cc
@@ -38,7 +38,18 @@ get_keywords ()
   return m;
 }
 
-const std::map<std::string, TokenId> Keywords::keywords = get_keywords ();
+const std::map<std::string, TokenId> Keywords::keywords_tokens
+  = get_keywords ();
+
+const std::set<std::string> Keywords::keywords = {
+#define RS_TOKEN(x, y)
+#define RS_TOKEN_KEYWORD_2015(tok, key) {key},
+#define RS_TOKEN_KEYWORD_2018 RS_TOKEN_KEYWORD_2015
+  RS_KEYWORD_LIST
+#undef RS_TOKEN_KEYWORD_2015
+#undef RS_TOKEN_KEYWORD_2018
+#undef RS_TOKEN
+};
 
 } // namespace Values
 } // namespace Rust
diff --git a/gcc/rust/util/rust-keyword-values.h b/gcc/rust/util/rust-keyword-values.h
index 4a6f1df525d0..01c98a2cde45 100644
--- a/gcc/rust/util/rust-keyword-values.h
+++ b/gcc/rust/util/rust-keyword-values.h
@@ -21,6 +21,14 @@
 
 #include "rust-token.h"
 
+// Append keywords made from multiple tokens to the existing token-keyword list
+#define RS_KEYWORD_LIST                                                        \
+  RS_TOKEN_LIST                                                                \
+  RS_TOKEN_KEYWORD_2015 (DOLLAR_CRATE, "$crate")                               \
+  RS_TOKEN_KEYWORD_2015 (PATH_ROOT, "{{root}}")                                \
+  RS_TOKEN_KEYWORD_2015 (STATIC_LIFETIME, "'static")                           \
+  RS_TOKEN_KEYWORD_2015 (UNDERSCORE_LIFETIME, "'_")
+
 namespace Rust {
 namespace Values {
 
@@ -28,14 +36,15 @@ namespace Values {
 class Keywords
 {
 public:
-  const static std::map<std::string, TokenId> keywords;
+  const static std::map<std::string, TokenId> keywords_tokens;
 
+  const static std::set<std::string> keywords;
   // Rust keyword values
 public:
 #define RS_TOKEN(x, y)
 #define RS_TOKEN_KEYWORD_2015(tok, key) static constexpr auto &tok = key;
 #define RS_TOKEN_KEYWORD_2018 RS_TOKEN_KEYWORD_2015
-  RS_TOKEN_LIST
+  RS_KEYWORD_LIST
 #undef RS_TOKEN_KEYWORD_2015
 #undef RS_TOKEN_KEYWORD_2018
 #undef RS_TOKEN