Subzero: Fix labels for block profiling.

src/IceClFlags.cpp

 //===- subzero/src/IceClFlags.cpp - Command line flags and parsing --------===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 ///
 /// \file
@@ skipping 58 matching lines @@
 // Note: Modifiable only if ALLOW_DISABLE_IR_GEN.
 cl::opt<bool> DisableIRGeneration("no-ir-gen",
                                   cl::desc("Disable generating Subzero IR."));
 cl::opt<bool> DisableTranslation("notranslate",
                                  cl::desc("Disable Subzero translation"));
 
 cl::opt<bool>
     DumpStats("szstats",
               cl::desc("Print statistics after translating each function"));
 
+// TODO(stichnot): The implementation of block profiling introduces some
+// oddities to be aware of.  First, empty basic blocks that don't normally
+// appear in the asm output, may be profiled anyway, so one might see profile
+// counts for blocks not in the original asm output.  Second, edge-split nodes
+// for advanced phi lowering are added too late, at which point it is not
+// practical to add profiling.
 cl::opt<bool> EnableBlockProfile(
     "enable-block-profile",
     cl::desc("If true, instrument basic blocks, and output profiling "
              "information to stdout at the end of program execution."),
     cl::init(false));
 
 cl::opt<bool>
     ForceMemIntrinOpt("fmem-intrin-opt",
                       cl::desc("Force optimization of memory intrinsics."));
 
@@ skipping 374 matching lines @@
   OutFlagsExtra.setGenerateBuildAtts(GenerateBuildAtts);
   OutFlagsExtra.setLLVMVerboseErrors(LLVMVerboseErrors);
   OutFlagsExtra.setAppName(AppName);
   OutFlagsExtra.setInputFileFormat(InputFileFormat);
   OutFlagsExtra.setIRFilename(IRFilename);
   OutFlagsExtra.setLogFilename(LogFilename);
   OutFlagsExtra.setOutputFilename(OutputFilename);
 }
 
 } // end of namespace Ice