[clang-tools-extra] dc63ad8 - [pseudo] Eliminate dependencies from clang-pseudo-gen. NFC

[Sam McCall via cfe-commits]

Author: Sam McCall
Date: 2022-06-03T20:42:38+02:00
New Revision: dc63ad8878de6d0b5dc1268691f48035e9234763

URL: https://github.com/llvm/llvm-project/commit/dc63ad8878de6d0b5dc1268691f48035e9234763
DIFF: https://github.com/llvm/llvm-project/commit/dc63ad8878de6d0b5dc1268691f48035e9234763.diff

LOG: [pseudo] Eliminate dependencies from clang-pseudo-gen. NFC

ClangBasic dependency eliminated by replacing our usage of
tok::getPunctuatorSpelling etc with direct use of the *.def file.

Implicit dependencies on clang-tablegen-targets removed as we manage to avoid
any transitive tablegen deps.

After these changes, `ninja clean; ninja pseudo-gen` runs 169 actions only
(basically Support and Demangle).

Differential Revision: https://reviews.llvm.org/D126731

Added: 
    

Modified: 
    clang-tools-extra/pseudo/gen/CMakeLists.txt
    clang-tools-extra/pseudo/lib/grammar/CMakeLists.txt
    clang-tools-extra/pseudo/lib/grammar/Grammar.cpp

Removed: 
    


################################################################################
diff  --git a/clang-tools-extra/pseudo/gen/CMakeLists.txt b/clang-tools-extra/pseudo/gen/CMakeLists.txt
index a104e05b53da9..25c7596c754f7 100644
--- a/clang-tools-extra/pseudo/gen/CMakeLists.txt
+++ b/clang-tools-extra/pseudo/gen/CMakeLists.txt
@@ -1,4 +1,5 @@
 set(LLVM_LINK_COMPONENTS Support)
+list(REMOVE_ITEM LLVM_COMMON_DEPENDS clang-tablegen-targets)
 
 add_clang_executable(pseudo-gen
   Main.cpp

diff  --git a/clang-tools-extra/pseudo/lib/grammar/CMakeLists.txt b/clang-tools-extra/pseudo/lib/grammar/CMakeLists.txt
index d50cb7df2a2cc..f7ada93eeb60b 100644
--- a/clang-tools-extra/pseudo/lib/grammar/CMakeLists.txt
+++ b/clang-tools-extra/pseudo/lib/grammar/CMakeLists.txt
@@ -1,18 +1,15 @@
 set(LLVM_LINK_COMPONENTS Support)
 
-# This library intents to keep as minimal dependencies as possible, it is a base
-# library of the cxx generator, to avoid creating long dep paths in the build
-# graph.
+# This library is used by the clang-pseudo-gen tool which runs at build time.
+# Dependencies should be minimal to avoid long dep paths in the build graph.
+# It does use clangBasic headers (tok::TokenKind), but linking is not needed.
+# We have no transitive dependencies on tablegen files.
+list(REMOVE_ITEM LLVM_COMMON_DEPENDS clang-tablegen-targets)
 add_clang_library(clangPseudoGrammar
   Grammar.cpp
   GrammarBNF.cpp
   LRGraph.cpp
   LRTable.cpp
   LRTableBuild.cpp
-
-  # FIXME: can we get rid of the clangBasic dependency? We need it for the
-  # clang::tok::getTokenName and clang::tok::getPunctuatorSpelling functions, we
-  # could consider remimplement these functions.
-  LINK_LIBS
-  clangBasic
   )
+

diff  --git a/clang-tools-extra/pseudo/lib/grammar/Grammar.cpp b/clang-tools-extra/pseudo/lib/grammar/Grammar.cpp
index e048f8753d9d9..d974d807d2547 100644
--- a/clang-tools-extra/pseudo/lib/grammar/Grammar.cpp
+++ b/clang-tools-extra/pseudo/lib/grammar/Grammar.cpp
@@ -167,19 +167,16 @@ std::vector<llvm::DenseSet<SymbolID>> followSets(const Grammar &G) {
 }
 
 static llvm::ArrayRef<std::string> getTerminalNames() {
-  static const std::vector<std::string> *TerminalNames = []() {
-    static std::vector<std::string> TerminalNames;
-    TerminalNames.reserve(NumTerminals);
-    for (unsigned I = 0; I < NumTerminals; ++I) {
-      tok::TokenKind K = static_cast<tok::TokenKind>(I);
-      if (const auto *Punc = tok::getPunctuatorSpelling(K))
-        TerminalNames.push_back(Punc);
-      else
-        TerminalNames.push_back(llvm::StringRef(tok::getTokenName(K)).upper());
-    }
-    return &TerminalNames;
+  static const auto &TerminalNames = []() {
+    auto &TerminalNames = *new std::array<std::string, NumTerminals>;
+#define PUNCTUATOR(Tok, Spelling) TerminalNames[tok::Tok] = Spelling;
+#define KEYWORD(Keyword, Condition)                                            \
+  TerminalNames[tok::kw_##Keyword] = llvm::StringRef(#Keyword).upper();
+#define TOK(Tok) TerminalNames[tok::Tok] = llvm::StringRef(#Tok).upper();
+#include "clang/Basic/TokenKinds.def"
+    return TerminalNames;
   }();
-  return *TerminalNames;
+  return TerminalNames;
 }
 GrammarTable::GrammarTable() : Terminals(getTerminalNames()) {}