- Make the machine cse dumb coalescer (as opposed to the more awesome simple

coalescer) handle sub-register classes.
- Add heuristics to avoid non-profitable cse. Given the current lack of live
  range splitting, avoid cse when an expression has PHI use and the would be
  new use is in a BB where the expression wasn't already being used.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@98043 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/LLVMTargetMachine.cpp

@@ -328,11 +328,11 @@ bool LLVMTargetMachine::addCommonCodeGenPasses(PassManagerBase &PM,
     PM.add(createOptimizeExtsPass());
     if (!DisableMachineLICM)
       PM.add(createMachineLICMPass());
-    if (EnableMachineCSE)
+    //if (EnableMachineCSE)
       PM.add(createMachineCSEPass());
     if (!DisableMachineSink)
       PM.add(createMachineSinkingPass());
-    printAndVerify(PM, "After MachineLICM and MachineSinking",
+    printAndVerify(PM, "After Machine LICM, CSE and Sinking passes",
                    /* allowDoubleDefs= */ true);
   }