[llvm-commits] [llvm] r161270 - in /llvm/trunk: include/llvm/CodeGen/Passes.h lib/CodeGen/LiveIntervalAnalysis.cpp lib/CodeGen/Passes.cpp

[Jakob Stoklund Olesen]

Author: stoklund
Date: Fri Aug  3 17:12:54 2012
New Revision: 161270

URL: http://llvm.org/viewvc/llvm-project?rev=161270&view=rev
Log:
Add an experimental -early-live-intervals option.

This option runs LiveIntervals before TwoAddressInstructionPass which
will eventually learn to exploit and update the analysis.

Eventually, LiveIntervals will run before PHIElimination, and we can get
rid of LiveVariables.

Modified:
    llvm/trunk/include/llvm/CodeGen/Passes.h
    llvm/trunk/lib/CodeGen/LiveIntervalAnalysis.cpp
    llvm/trunk/lib/CodeGen/Passes.cpp

Modified: llvm/trunk/include/llvm/CodeGen/Passes.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/CodeGen/Passes.h?rev=161270&r1=161269&r2=161270&view=diff
==============================================================================
--- llvm/trunk/include/llvm/CodeGen/Passes.h (original)
+++ llvm/trunk/include/llvm/CodeGen/Passes.h Fri Aug  3 17:12:54 2012
@@ -315,6 +315,10 @@
   ///  This pass is still in development
   extern char &StrongPHIEliminationID;
 
+  /// LiveIntervals - This analysis keeps track of the live ranges of virtual
+  /// and physical registers.
+  extern char &LiveIntervalsID;
+
   /// LiveStacks pass. An analysis keeping track of the liveness of stack slots.
   extern char &LiveStacksID;
 

Modified: llvm/trunk/lib/CodeGen/LiveIntervalAnalysis.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/LiveIntervalAnalysis.cpp?rev=161270&r1=161269&r2=161270&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/LiveIntervalAnalysis.cpp (original)
+++ llvm/trunk/lib/CodeGen/LiveIntervalAnalysis.cpp Fri Aug  3 17:12:54 2012
@@ -45,6 +45,7 @@
                  cl::desc("Use new algorithm forcomputing live intervals"));
 
 char LiveIntervals::ID = 0;
+char &llvm::LiveIntervalsID = LiveIntervals::ID;
 INITIALIZE_PASS_BEGIN(LiveIntervals, "liveintervals",
                 "Live Interval Analysis", false, false)
 INITIALIZE_AG_DEPENDENCY(AliasAnalysis)

Modified: llvm/trunk/lib/CodeGen/Passes.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/Passes.cpp?rev=161270&r1=161269&r2=161270&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/Passes.cpp (original)
+++ llvm/trunk/lib/CodeGen/Passes.cpp Fri Aug  3 17:12:54 2012
@@ -88,6 +88,10 @@
                    cl::desc("Print machine instrs"),
                    cl::value_desc("pass-name"), cl::init("option-unspecified"));
 
+// Experimental option to run live inteerval analysis early.
+static cl::opt<bool> EarlyLiveIntervals("early-live-intervals", cl::Hidden,
+    cl::desc("Run live interval analysis earlier in the pipeline"));
+
 /// Allow standard passes to be disabled by command line options. This supports
 /// simple binary flags that either suppress the pass or do nothing.
 /// i.e. -disable-mypass=false has no effect.
@@ -648,6 +652,11 @@
     addPass(&MachineLoopInfoID);
     addPass(&PHIEliminationID);
   }
+
+  // Eventually, we want to run LiveIntervals before PHI elimination.
+  if (EarlyLiveIntervals)
+    addPass(&LiveIntervalsID);
+
   addPass(&TwoAddressInstructionPassID);
 
   if (EnableStrongPHIElim)