For blocks that are not loop headers, just print their loop depth and header BB.

For loop headers, print Inner loop along with the other stuff so it doesn't take
an extra line.  We now get stuff like this:

LBB1_4:                                                     ## %land.end
                                                            ##   in Loop: Header=BB1_1 Depth=1
        notb    %al
        testb   $1, %al
        jne     LBB1_8

and:

LBB1_6:                                                     ## %while.cond7
                                                            ## Inner Loop Header: Depth=3
                                                            ##     Inside Loop BB1_5 Depth 2
                                                            ##   Inside Loop BB1_1 Depth 1

which still isn't great for loop headers, but is much less verbose.

llvm-svn: 94221

1 files changed, 16 insertions, 13 deletions

diff --git a/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp b/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
index 0b8633bf597..e0186d145f6 100644
--- a/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
@@ -1847,9 +1847,8 @@ void AsmPrinter::EmitComments(const MachineInstr &MI) const {
 
 /// PrintChildLoopComment - Print comments about child loops within
 /// the loop for this basic block, with nesting.
-static void PrintChildLoopComment(MCStreamer &O, const MachineLoop *Loop,
+static void PrintChildLoopComment(raw_ostream &OS, const MachineLoop *Loop,
                                   unsigned FunctionNumber) {
-  raw_ostream &OS = O.GetCommentOS();
   // Add child loop information
   for (MachineLoop::iterator CL = Loop->begin(), E = Loop->end();CL != E; ++CL){
     MachineBasicBlock *Header = (*CL)->getHeader();
@@ -1857,7 +1856,7 @@ static void PrintChildLoopComment(MCStreamer &O, const MachineLoop *Loop,
     OS.indent(((*CL)->getLoopDepth()-1)*2)
       << "Child Loop BB" << FunctionNumber << "_"
       << Header->getNumber() << " Depth " << (*CL)->getLoopDepth() << '\n';
-    PrintChildLoopComment(O, *CL, FunctionNumber);
+    PrintChildLoopComment(OS, *CL, FunctionNumber);
   }
 }
 
@@ -1869,23 +1868,27 @@ void AsmPrinter::EmitComments(const MachineBasicBlock &MBB) const {
   const MachineLoop *Loop = LI->getLoopFor(&MBB);
   if (Loop == 0) return;
 
-  OutStreamer.AddComment("Loop Depth " + Twine(Loop->getLoopDepth()));
-
   MachineBasicBlock *Header = Loop->getHeader();
   assert(Header && "No header for loop");
-  
+
+  // If this block is not a loop header, just print out what is the loop header
+  // and return.
   if (Header != &MBB) {
-    OutStreamer.AddComment("Loop Header is BB" + Twine(getFunctionNumber()) +
-                           "_" + Twine(Loop->getHeader()->getNumber()));
-  } else {
-    OutStreamer.AddComment("Loop Header");
-    PrintChildLoopComment(OutStreamer, Loop, getFunctionNumber());
+    OutStreamer.AddComment("  in Loop: Header=BB" + Twine(getFunctionNumber())+
+                           "_" + Twine(Loop->getHeader()->getNumber())+
+                           " Depth="+Twine(Loop->getLoopDepth()));
+    return;
   }
 
+  // Otherwise, it is a loop header.  Print out information about child and
+  // parent loops.
+  raw_ostream &OS = OutStreamer.GetCommentOS();
+
   if (Loop->empty())
-    OutStreamer.AddComment("Inner Loop");
+    OS << "Inner ";
+  OS << "Loop Header: Depth=" + Twine(Loop->getLoopDepth()) << '\n';
 
-  raw_ostream &OS = OutStreamer.GetCommentOS();
+  PrintChildLoopComment(OS, Loop, getFunctionNumber());
 
   // Add parent loop information.
   for (const MachineLoop *CurLoop = Loop->getParentLoop(); CurLoop;