Deprecate TR_TraceTempUsage with envvar

This tracing option counts the number of stores to temp slots by doing
a linear walk of the treetops. It seems overkill to have two separate
tracing optimizations for this, and it seems like something that would
be used during debugging anyways as this information can be obtained
otherwise via a simple grep.

In light of this we deprecate the two options related to tracing temp
counts, and rather than deleting the code we leave it under an envvar.

Signed-off-by: Filip Jeremic <fjeremic@ca.ibm.com>

Author: fjeremic

compiler/control/OMROptions.cpp

@@ -1215,8 +1215,6 @@ TR::OptionTable OMR::Options::_jitOptions[] = {
    {"traceStripMining",                 "L\ttrace strip mining",                           TR::Options::traceOptimization, stripMining, 0, "P"},
    {"traceStructuralAnalysis",          "L\ttrace structural analysis", SET_OPTION_BIT(TR_TraceSA), "P"},
    {"traceSwitchAnalyzer",              "L\ttrace switch analyzer",                        TR::Options::traceOptimization, switchAnalyzer, 0, "P"},
-   {"traceTempUsage",                   "L\ttrace number of temps used",                   SET_OPTION_BIT(TR_TraceTempUsage), "P"},
-   {"traceTempUsageMore",               "L\ttrace usage of temps, showing each temp used", SET_OPTION_BIT(TR_TraceTempUsageMore), "P"},
    {"traceTreeCleansing",               "L\ttrace tree cleansing",                         TR::Options::traceOptimization, treesCleansing, 0, "P"},
    {"traceTreePatternMatching",         "L\ttrace the functioning of the TR_Pattern framework", SET_OPTION_BIT(TR_TraceTreePatternMatching), "F"},
    {"traceTrees",                       "L\tdump trees after each compilation phase", SET_OPTION_BIT(TR_TraceTrees), "P" },

compiler/control/OMROptions.hpp

@@ -819,8 +819,8 @@ enum TR_CompilationOptions
    TR_DisableRecognizedMethods                        = 0x00000040 + 25,
    TR_DisableBitOpcode                                = 0x00000080 + 25,
    // Available                                       = 0x00000100 + 25,
-   TR_TraceTempUsage                                  = 0x00000200 + 25,
-   TR_TraceTempUsageMore                              = 0x00000400 + 25,
+   // Available                                       = 0x00000200 + 25,
+   // Available                                       = 0x00000400 + 25,
    // Available                                       = 0x00000800 + 25,
    // Available                                       = 0x00001000 + 25,
    TR_TracePREForOptimalSubNodeReplacement            = 0x00002000 + 25,

compiler/optimizer/OMROptimizer.cpp

@@ -2177,12 +2177,14 @@ int32_t OMR::Optimizer::performOptimization(const OptimizationStrategy *optimiza
 
       manager->performChecks();
 
-      if (comp()->getOption(TR_TraceTempUsage) || comp()->getOption(TR_TraceTempUsageMore))
+      static const bool enableCountTemps = feGetEnv("TR_EnableCountTemps") != NULL;
+      if (enableCountTemps)
          {
-          TR::TreeTop * tt = 0;
          int32_t tempCount = 0;
 
-         for (tt = getMethodSymbol()->getFirstTreeTop(); tt; tt = tt->getNextTreeTop())
+         traceMsg(comp(), "Temps seen (if any): ");
+
+         for (TR::TreeTop *tt = getMethodSymbol()->getFirstTreeTop(); tt; tt = tt->getNextTreeTop())
             {
             TR::Node * ttNode = tt->getNode();
 
@@ -2198,41 +2200,13 @@ int32_t OMR::Optimizer::performOptimization(const OptimizationStrategy *optimiza
                if ((symRef->getSymbol()->getKind() == TR::Symbol::IsAutomatic) &&
                    symRef->isTemporary(comp()))
                   {
-                  tempCount += 1;
-                  }
-               }
-            }
-
-         comp()->getDebug()->trace("Number of temps seen = %d", tempCount);
-
-         if (comp()->getOption(TR_TraceTempUsageMore) &&
-             (tempCount > 0))
-            {
-            comp()->getDebug()->trace(": ");
-
-            for (tt = getMethodSymbol()->getFirstTreeTop(); tt; tt = tt->getNextTreeTop())
-               {
-               TR::Node * ttNode = tt->getNode();
-
-               if (ttNode->getOpCodeValue() == TR::treetop)
-                  {
-                  ttNode = ttNode->getFirstChild();
-                  }
-
-               if (ttNode->getOpCode().isStore() && ttNode->getOpCode().hasSymbolReference())
-                  {
-                  TR::SymbolReference * symRef = ttNode->getSymbolReference();
-
-                  if ((symRef->getSymbol()->getKind() == TR::Symbol::IsAutomatic) &&
-                      symRef->isTemporary(comp()))
-                     {
-                     comp()->getDebug()->trace("%s ", comp()->getDebug()->getName(ttNode->getSymbolReference()));
-                     }
+                  ++tempCount;
+                  traceMsg(comp(), "%s ", comp()->getDebug()->getName(ttNode->getSymbolReference()));
                   }
                }
             }
 
-         comp()->getDebug()->trace("\n");
+         traceMsg(comp(), "\nNumber of temps seen = %d\n", tempCount);
          }
 
       if (comp()->getOption(TR_TraceOptDetails) || comp()->getOption(TR_TraceOptTrees))