Fix MemoryBuffer::getSTDIN to *not* return null if stdin is empty, this is a lame...

[oota-llvm.git] / lib / Support / SourceMgr.cpp

diff --git a/lib/Support/SourceMgr.cpp b/lib/Support/SourceMgr.cpp
index 5460cb3824d5fbeba8920363c8abe73bec4dcf2d..4b93f7f99a24b22950db0663ac0004da8b68ade2 100644 (file)
--- a/lib/Support/SourceMgr.cpp
+++ b/lib/Support/SourceMgr.cpp
@@ -18,7 +18,24 @@
 #include "llvm/Support/raw_ostream.h"
 using namespace llvm;
 
+namespace {
+  struct LineNoCacheTy {
+    int LastQueryBufferID;
+    const char *LastQuery;
+    unsigned LineNoOfQuery;
+  };
+}
+
+static LineNoCacheTy *getCache(void *Ptr) {
+  return (LineNoCacheTy*)Ptr;
+}
+
+
 SourceMgr::~SourceMgr() {
+  // Delete the line # cache if allocated.
+  if (LineNoCacheTy *Cache = getCache(LineNoCache))
+    delete Cache;
+    
   while (!Buffers.empty()) {
     delete Buffers.back().Buffer;
     Buffers.pop_back();
@@ -71,57 +88,128 @@ unsigned SourceMgr::FindLineNumber(SMLoc Loc, int BufferID) const {
   
   const char *Ptr = Buff->getBufferStart();
 
+  // If we have a line number cache, and if the query is to a later point in the
+  // same file, start searching from the last query location.  This optimizes
+  // for the case when multiple diagnostics come out of one file in order.
+  if (LineNoCacheTy *Cache = getCache(LineNoCache))
+    if (Cache->LastQueryBufferID == BufferID && 
+        Cache->LastQuery <= Loc.getPointer()) {
+      Ptr = Cache->LastQuery;
+      LineNo = Cache->LineNoOfQuery;
+    }
+
+  // Scan for the location being queried, keeping track of the number of lines
+  // we see.
   for (; SMLoc::getFromPointer(Ptr) != Loc; ++Ptr)
     if (*Ptr == '\n') ++LineNo;
+  
+  
+  // Allocate the line number cache if it doesn't exist.
+  if (LineNoCache == 0)
+    LineNoCache = new LineNoCacheTy();
+  
+  // Update the line # cache.
+  LineNoCacheTy &Cache = *getCache(LineNoCache);
+  Cache.LastQueryBufferID = BufferID;
+  Cache.LastQuery = Ptr;
+  Cache.LineNoOfQuery = LineNo;
   return LineNo;
 }
 
-void SourceMgr::PrintIncludeStack(SMLoc IncludeLoc) const {
+void SourceMgr::PrintIncludeStack(SMLoc IncludeLoc, raw_ostream &OS) const {
   if (IncludeLoc == SMLoc()) return;  // Top of stack.
   
   int CurBuf = FindBufferContainingLoc(IncludeLoc);
   assert(CurBuf != -1 && "Invalid or unspecified location!");
 
-  PrintIncludeStack(getBufferInfo(CurBuf).IncludeLoc);
+  PrintIncludeStack(getBufferInfo(CurBuf).IncludeLoc, OS);
   
-  errs() << "Included from "
-         << getBufferInfo(CurBuf).Buffer->getBufferIdentifier()
-         << ":" << FindLineNumber(IncludeLoc, CurBuf) << ":\n";
+  OS << "Included from "
+     << getBufferInfo(CurBuf).Buffer->getBufferIdentifier()
+     << ":" << FindLineNumber(IncludeLoc, CurBuf) << ":\n";
 }
 
 
-void SourceMgr::PrintError(SMLoc ErrorLoc, const std::string &Msg) const {
-  raw_ostream &OS = errs();
+/// GetMessage - Return an SMDiagnostic at the specified location with the
+/// specified string.
+///
+/// @param Type - If non-null, the kind of message (e.g., "error") which is
+/// prefixed to the message.
+SMDiagnostic SourceMgr::GetMessage(SMLoc Loc, const std::string &Msg,
+                                   const char *Type) const {
   
   // First thing to do: find the current buffer containing the specified
   // location.
-  int CurBuf = FindBufferContainingLoc(ErrorLoc);
+  int CurBuf = FindBufferContainingLoc(Loc);
   assert(CurBuf != -1 && "Invalid or unspecified location!");
   
-  PrintIncludeStack(getBufferInfo(CurBuf).IncludeLoc);
-  
   MemoryBuffer *CurMB = getBufferInfo(CurBuf).Buffer;
   
   
-  OS << "Parsing " << CurMB->getBufferIdentifier() << ":"
-     << FindLineNumber(ErrorLoc, CurBuf) << ": ";
-  
-  OS << Msg << "\n";
-  
   // Scan backward to find the start of the line.
-  const char *LineStart = ErrorLoc.getPointer();
+  const char *LineStart = Loc.getPointer();
   while (LineStart != CurMB->getBufferStart() && 
          LineStart[-1] != '\n' && LineStart[-1] != '\r')
     --LineStart;
   // Get the end of the line.
-  const char *LineEnd = ErrorLoc.getPointer();
+  const char *LineEnd = Loc.getPointer();
   while (LineEnd != CurMB->getBufferEnd() && 
          LineEnd[0] != '\n' && LineEnd[0] != '\r')
     ++LineEnd;
+  
+  std::string PrintedMsg;
+  if (Type) {
+    PrintedMsg = Type;
+    PrintedMsg += ": ";
+  }
+  PrintedMsg += Msg;
+  
   // Print out the line.
-  OS << std::string(LineStart, LineEnd) << "\n";
-  // Print out spaces before the caret.
-  for (const char *Pos = LineStart; Pos != ErrorLoc.getPointer(); ++Pos)
-    OS << (*Pos == '\t' ? '\t' : ' ');
-  OS << "^\n";
+  return SMDiagnostic(CurMB->getBufferIdentifier(), FindLineNumber(Loc, CurBuf),
+                      Loc.getPointer()-LineStart, PrintedMsg,
+                      std::string(LineStart, LineEnd));
 }
+
+void SourceMgr::PrintMessage(SMLoc Loc, const std::string &Msg, 
+                             const char *Type) const {
+  raw_ostream &OS = errs();
+
+  int CurBuf = FindBufferContainingLoc(Loc);
+  assert(CurBuf != -1 && "Invalid or unspecified location!");
+  PrintIncludeStack(getBufferInfo(CurBuf).IncludeLoc, OS);
+
+  GetMessage(Loc, Msg, Type).Print(0, OS);
+}
+
+//===----------------------------------------------------------------------===//
+// SMDiagnostic Implementation
+//===----------------------------------------------------------------------===//
+
+void SMDiagnostic::Print(const char *ProgName, raw_ostream &S) {
+  if (ProgName && ProgName[0])
+    S << ProgName << ": ";
+
+  if (Filename == "-")
+    S << "<stdin>";
+  else
+    S << Filename;
+  
+  if (LineNo != -1) {
+    S << ':' << LineNo;
+    if (ColumnNo != -1)
+      S << ':' << (ColumnNo+1);
+  }
+  
+  S << ": " << Message << '\n';
+  
+  if (LineNo != -1 && ColumnNo != -1) {
+    S << LineContents << '\n';
+    
+    // Print out spaces/tabs before the caret.
+    for (unsigned i = 0; i != unsigned(ColumnNo); ++i)
+      S << (LineContents[i] == '\t' ? '\t' : ' ');
+    S << "^\n";
+  }
+}
+
+