From aacef757ed3e34dba974a046a51e18c152a3428e Mon Sep 17 00:00:00 2001
From: Dmitri Hrybenko <dgribenko@apple.com>
Date: Fri, 9 Aug 2013 22:50:58 +0000
Subject: [PATCH] Move decompose from PrettyStackTrace.cpp to the SourceManager

It requires direct access to the SourceLoc internals and is generally useful
anyway.


Swift SVN r7111
---
 include/swift/Basic/SourceManager.h | 10 ++++++++++
 lib/AST/PrettyStackTrace.cpp        | 26 ++++----------------------
 lib/Basic/SourceLoc.cpp             | 21 +++++++++++++++++++++
 3 files changed, 35 insertions(+), 22 deletions(-)

diff --git a/include/swift/Basic/SourceManager.h b/include/swift/Basic/SourceManager.h
index 2f19f563f82..a66df8a2075 100644
--- a/include/swift/Basic/SourceManager.h
+++ b/include/swift/Basic/SourceManager.h
@@ -18,6 +18,14 @@
 
 namespace swift {
 
+/// \brief A decomposed representation of a source location, useful for
+/// printing diagnostics.
+struct DecomposedLoc {
+  const llvm::MemoryBuffer *Buffer;
+  unsigned Line;
+  unsigned Column;
+};
+
 /// \brief This class manages and owns source buffers.
 class SourceManager {
   llvm::SourceMgr LLVMSourceMgr;
@@ -91,6 +99,8 @@ public:
 
   /// \brief Returns the offset in bytes for the given source location.
   unsigned getLocOffsetInBuffer(SourceLoc Loc, unsigned BufferID) const;
+
+  DecomposedLoc decompose(SourceLoc Loc) const;
 };
 
 } // namespace swift
diff --git a/lib/AST/PrettyStackTrace.cpp b/lib/AST/PrettyStackTrace.cpp
index 524d046b305..ef4ca3250b9 100644
--- a/lib/AST/PrettyStackTrace.cpp
+++ b/lib/AST/PrettyStackTrace.cpp
@@ -25,29 +25,11 @@
 
 using namespace swift;
 
-struct DecomposedLoc {
-  llvm::MemoryBuffer *Buffer;
-  unsigned Line;
-  unsigned Column;
-};
+static Optional<DecomposedLoc> decompose(SourceManager &SM, SourceLoc Loc) {
+  if (!Loc.isValid())
+    return Nothing;
 
-static Optional<DecomposedLoc> decompose(SourceManager &SM, SourceLoc loc) {
-  if (!loc.isValid()) return Nothing;
-
-  int bufferIndex = SM->FindBufferContainingLoc(loc.Value);
-  if (bufferIndex == -1) return Nothing;
-
-  DecomposedLoc result;
-  result.Buffer = SM->getBufferInfo(bufferIndex).Buffer;
-  result.Line = SM->FindLineNumber(loc.Value, bufferIndex);
-
-  const char *lineStart = loc.Value.getPointer();
-  while (lineStart != result.Buffer->getBufferStart() &&
-         lineStart[-1] != '\n' && lineStart[-1] != '\r')
-    --lineStart;
-  result.Column = loc.Value.getPointer() - lineStart;
-
-  return result;
+  return SM.decompose(Loc);
 }
 
 static void printDecomposedLoc(llvm::raw_ostream &out,
diff --git a/lib/Basic/SourceLoc.cpp b/lib/Basic/SourceLoc.cpp
index 1c821aec4a9..20859f5b74a 100644
--- a/lib/Basic/SourceLoc.cpp
+++ b/lib/Basic/SourceLoc.cpp
@@ -36,6 +36,27 @@ unsigned SourceManager::getLocOffsetInBuffer(SourceLoc Loc,
   return Loc.Value.getPointer() - Buffer->getBuffer().begin();
 }
 
+DecomposedLoc SourceManager::decompose(SourceLoc Loc) const {
+  assert(Loc.isValid());
+
+  unsigned BufferID =
+      unsigned(LLVMSourceMgr.FindBufferContainingLoc(Loc.Value));
+  assert(BufferID != ~0U);
+
+  DecomposedLoc Result;
+  Result.Buffer = LLVMSourceMgr.getMemoryBuffer(BufferID);
+  Result.Line = LLVMSourceMgr.FindLineNumber(Loc.Value, BufferID);
+
+  const char *BufferStart = Result.Buffer->getBufferStart();
+  const char *LineStart = Loc.Value.getPointer();
+  while (LineStart != BufferStart &&
+         LineStart[-1] != '\n' && LineStart[-1] != '\r')
+    --LineStart;
+  Result.Column = Loc.Value.getPointer() - LineStart;
+
+  return Result;
+}
+
 void SourceLoc::printLineAndColon(raw_ostream &OS,
                                   const SourceManager &SM) const {
   int BufferIndex = SM->FindBufferContainingLoc(Value);