Revamp the SourceManager to separate the representation of parsed

source locations from source locations loaded from an AST/PCH file.

Previously, loading an AST/PCH file involved carefully pre-allocating
space at the beginning of the source manager for the source locations
and FileIDs that correspond to the prefix, and then appending the
source locations/FileIDs used for parsing the remaining translation
unit. This design forced us into loading PCH files early, as a prefix,
whic has become a rather significant limitation.

This patch splits the SourceManager space into two parts: for source
location "addresses", the lower values (growing upward) are used to
describe parsed code, while upper values (growing downward) are used
for source locations loaded from AST/PCH files. Similarly, positive
FileIDs are used to describe parsed code while negative FileIDs are
used to file/macro locations loaded from AST/PCH files. As a result,
we can load PCH/AST files even during parsing, making various
improvemnts in the future possible, e.g., teaching #include <foo.h> to
look for and load <foo.h.gch> if it happens to be already available.

This patch was originally written by Sebastian Redl, then brought
forward to the modern age by Jonathan Turner, and finally
polished/finished by me to be committed.




git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@135484 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 10 insertions, 0 deletions

diff --git a/lib/Basic/Diagnostic.cpp b/lib/Basic/Diagnostic.cpp
index ae363a0df0..c12651a3f9 100644
--- a/lib/Basic/Diagnostic.cpp
+++ b/lib/Basic/Diagnostic.cpp
@@ -726,6 +726,16 @@ StoredDiagnostic::StoredDiagnostic(Diagnostic::Level Level,
     FixIts.push_back(Info.getFixItHint(I));
 }
 
+StoredDiagnostic::StoredDiagnostic(Diagnostic::Level Level, unsigned ID, 
+                                   llvm::StringRef Message, FullSourceLoc Loc,
+                                   llvm::ArrayRef<CharSourceRange> Ranges,
+                                   llvm::ArrayRef<FixItHint> Fixits)
+  : ID(ID), Level(Level), Loc(Loc), Message(Message) 
+{
+  this->Ranges.assign(Ranges.begin(), Ranges.end());
+  this->FixIts.assign(FixIts.begin(), FixIts.end());
+}
+
 StoredDiagnostic::~StoredDiagnostic() { }
 
 /// IncludeInDiagnosticCounts - This method (whose default implementation