Teach Preprocessor::macro_begin/macro_end to lazily load all macro

definitions from a precompiled header. This ensures that
code-completion with macro names behaves the same with or without
precompiled headers.

llvm-svn: 92497

2 files changed, 32 insertions, 4 deletions

diff --git a/clang/lib/Lex/PPLexerChange.cpp b/clang/lib/Lex/PPLexerChange.cpp
index ce1b19ca7c1..0b26ccbecba 100644
--- a/clang/lib/Lex/PPLexerChange.cpp
+++ b/clang/lib/Lex/PPLexerChange.cpp
@@ -249,7 +249,8 @@ bool Preprocessor::HandleEndOfFile(Token &Result, bool isEndOfMacro) {
   // diagnostic is enabled, look for macros that have not been used.
   if (getDiagnostics().getDiagnosticLevel(diag::pp_macro_not_used) !=
         Diagnostic::Ignored) {
-    for (macro_iterator I = macro_begin(), E = macro_end(); I != E; ++I)
+    for (macro_iterator I = macro_begin(false), E = macro_end(false); 
+         I != E; ++I)
       if (!I->second->isUsed())
         Diag(I->second->getDefinitionLoc(), diag::pp_macro_not_used);
   }
diff --git a/clang/lib/Lex/Preprocessor.cpp b/clang/lib/Lex/Preprocessor.cpp
index 81966cb2b91..26bb3a90dac 100644
--- a/clang/lib/Lex/Preprocessor.cpp
+++ b/clang/lib/Lex/Preprocessor.cpp
@@ -27,6 +27,7 @@
 
 #include "clang/Lex/Preprocessor.h"
 #include "MacroArgs.h"
+#include "clang/Lex/ExternalPreprocessorSource.h"
 #include "clang/Lex/HeaderSearch.h"
 #include "clang/Lex/MacroInfo.h"
 #include "clang/Lex/Pragma.h"
@@ -43,6 +44,7 @@
 using namespace clang;
 
 //===----------------------------------------------------------------------===//
+ExternalPreprocessorSource::~ExternalPreprocessorSource() { }
 
 Preprocessor::Preprocessor(Diagnostic &diags, const LangOptions &opts,
                            const TargetInfo &target, SourceManager &SM,
@@ -50,9 +52,9 @@ Preprocessor::Preprocessor(Diagnostic &diags, const LangOptions &opts,
                            IdentifierInfoLookup* IILookup,
                            bool OwnsHeaders)
   : Diags(&diags), Features(opts), Target(target),FileMgr(Headers.getFileMgr()),
-    SourceMgr(SM), HeaderInfo(Headers), Identifiers(opts, IILookup),
-    BuiltinInfo(Target), CodeCompletionFile(0), CurPPLexer(0), CurDirLookup(0),
-    Callbacks(0), MacroArgCache(0) {
+    SourceMgr(SM), HeaderInfo(Headers), ExternalSource(0),
+    Identifiers(opts, IILookup), BuiltinInfo(Target), CodeCompletionFile(0), 
+    CurPPLexer(0), CurDirLookup(0), Callbacks(0), MacroArgCache(0) {
   ScratchBuf = new ScratchBuffer(SourceMgr);
   CounterValue = 0; // __COUNTER__ starts at 0.
   OwnsHeaderSearch = OwnsHeaders;
@@ -77,6 +79,9 @@ Preprocessor::Preprocessor(Diagnostic &diags, const LangOptions &opts,
 
   CachedLexPos = 0;
 
+  // We haven't read anything from the external source.
+  ReadMacrosFromExternalSource = false;
+      
   // "Poison" __VA_ARGS__, which can only appear in the expansion of a macro.
   // This gets unpoisoned where it is allowed.
   (Ident__VA_ARGS__ = getIdentifierInfo("__VA_ARGS__"))->setIsPoisoned();
@@ -194,6 +199,28 @@ void Preprocessor::PrintStats() {
              << NumFastTokenPaste << " on the fast path.\n";
 }
 
+Preprocessor::macro_iterator 
+Preprocessor::macro_begin(bool IncludeExternalMacros) const { 
+  if (IncludeExternalMacros && ExternalSource && 
+      !ReadMacrosFromExternalSource) {
+    ReadMacrosFromExternalSource = true;
+    ExternalSource->ReadDefinedMacros();
+  }
+  
+  return Macros.begin(); 
+}
+
+Preprocessor::macro_iterator 
+Preprocessor::macro_end(bool IncludeExternalMacros) const { 
+  if (IncludeExternalMacros && ExternalSource && 
+      !ReadMacrosFromExternalSource) {
+    ReadMacrosFromExternalSource = true;
+    ExternalSource->ReadDefinedMacros();
+  }
+  
+  return Macros.end(); 
+}
+
 bool Preprocessor::SetCodeCompletionPoint(const FileEntry *File, 
                                           unsigned TruncateAtLine, 
                                           unsigned TruncateAtColumn) {