Use the AST on-disk hash table for name lookup inside a DeclContext.

*Huge* improvement over the amount of deserializing that we do for C++ lookup.
e.g, if he have the Carbon header precompiled and include it on a file containing this:

int x;

these are the before/after stats:

BEFORE:

*** AST File Statistics:
  578 stat cache hits
  4 stat cache misses
  548/30654 source location entries read (1.787695%)
  15907/16501 types read (96.400223%)
  53525/59955 declarations read (89.275291%)
  33993/43525 identifiers read (78.099945%)
  41516/51891 statements read (80.006165%)
  77/5317 macros read (1.448185%)
  0/6335 lexical declcontexts read (0.000000%)
  1/5424 visible declcontexts read (0.018437%)

AFTER using the on-disk table:

*** AST File Statistics:
  578 stat cache hits
  4 stat cache misses
  548/30654 source location entries read (1.787695%)
  10/16501 types read (0.060602%)
  9/59955 declarations read (0.015011%)
  161/43525 identifiers read (0.369902%)
  20/51891 statements read (0.038542%)
  6/5317 macros read (0.112846%)
  0/6335 lexical declcontexts read (0.000000%)
  2/5424 visible declcontexts read (0.036873%)

There's only one issue affecting mostly the precompiled preambles which I will address soon.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@111636 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 0 insertions, 32 deletions

diff --git a/lib/Serialization/ASTReaderDecl.cpp b/lib/Serialization/ASTReaderDecl.cpp
index 9094281cd4..bc68e91e3e 100644
--- a/lib/Serialization/ASTReaderDecl.cpp
+++ b/lib/Serialization/ASTReaderDecl.cpp
@@ -1413,35 +1413,3 @@ Decl *ASTReader::ReadDeclRecord(unsigned Index, DeclID ID) {
 
   return D;
 }
-
-bool ASTReader::ReadDeclContextStorage(llvm::BitstreamCursor &Cursor,
-                                   const std::pair<uint64_t, uint64_t> &Offsets,
-                                       DeclContextInfo &Info) {
-  SavedStreamPosition SavedPosition(Cursor);
-  // First the lexical decls.
-  if (Offsets.first != 0) {
-    Cursor.JumpToBit(Offsets.first);
-
-    RecordData Record;
-    const char *Blob;
-    unsigned BlobLen;
-    unsigned Code = Cursor.ReadCode();
-    unsigned RecCode = Cursor.ReadRecord(Code, Record, &Blob, &BlobLen);
-    if (RecCode != DECL_CONTEXT_LEXICAL) {
-      Error("Expected lexical block");
-      return true;
-    }
-
-    Info.LexicalDecls = reinterpret_cast<const DeclID*>(Blob);
-    Info.NumLexicalDecls = BlobLen / sizeof(DeclID);
-  } else {
-    Info.LexicalDecls = 0;
-    Info.NumLexicalDecls = 0;
-  }
-
-  // Now the visible decls.
-  Info.Stream = &Cursor;
-  Info.OffsetToVisibleDecls = Offsets.second;
-
-  return false;
-}