Revert r140097, working on a better approach

[oota-llvm.git] / lib / CodeGen / RegAllocLinearScan.cpp

diff --git a/lib/CodeGen/RegAllocLinearScan.cpp b/lib/CodeGen/RegAllocLinearScan.cpp
index 3b37f4a345d3cab706f60f83a923b1af8ae16bdc..ce3fb90b1126ad00d0b6bf810c0a1c18ecf8b56a 100644 (file)
--- a/lib/CodeGen/RegAllocLinearScan.cpp
+++ b/lib/CodeGen/RegAllocLinearScan.cpp
@@ -28,7 +28,6 @@
 #include "llvm/CodeGen/MachineRegisterInfo.h"
 #include "llvm/CodeGen/Passes.h"
 #include "llvm/CodeGen/RegAllocRegistry.h"
-#include "llvm/CodeGen/RegisterCoalescer.h"
 #include "llvm/Target/TargetRegisterInfo.h"
 #include "llvm/Target/TargetMachine.h"
 #include "llvm/Target/TargetOptions.h"
@@ -57,11 +56,6 @@ NewHeuristic("new-spilling-heuristic",
              cl::desc("Use new spilling heuristic"),
              cl::init(false), cl::Hidden);
 
-static cl::opt<bool>
-PreSplitIntervals("pre-alloc-split",
-                  cl::desc("Pre-register allocation live interval splitting"),
-                  cl::init(false), cl::Hidden);
-
 static cl::opt<bool>
 TrivCoalesceEnds("trivial-coalesce-ends",
                   cl::desc("Attempt trivial coalescing of interval ends"),
@@ -101,10 +95,9 @@ namespace {
       initializeLiveDebugVariablesPass(*PassRegistry::getPassRegistry());
       initializeLiveIntervalsPass(*PassRegistry::getPassRegistry());
       initializeStrongPHIEliminationPass(*PassRegistry::getPassRegistry());
-      initializeRegisterCoalescerAnalysisGroup(
+      initializeRegisterCoalescerPass(
         *PassRegistry::getPassRegistry());
       initializeCalculateSpillWeightsPass(*PassRegistry::getPassRegistry());
-      initializePreAllocSplittingPass(*PassRegistry::getPassRegistry());
       initializeLiveStacksPass(*PassRegistry::getPassRegistry());
       initializeMachineDominatorTreePass(*PassRegistry::getPassRegistry());
       initializeMachineLoopInfoPass(*PassRegistry::getPassRegistry());
@@ -215,10 +208,8 @@ namespace {
         AU.addRequiredID(StrongPHIEliminationID);
       // Make sure PassManager knows which analyses to make available
       // to coalescing and which analyses coalescing invalidates.
-      AU.addRequiredTransitive<RegisterCoalescer>();
+      AU.addRequiredTransitiveID(RegisterCoalescerPassID);
       AU.addRequired<CalculateSpillWeights>();
-      if (PreSplitIntervals)
-        AU.addRequiredID(PreAllocSplittingID);
       AU.addRequiredID(LiveStacksID);
       AU.addPreservedID(LiveStacksID);
       AU.addRequired<MachineLoopInfo>();
@@ -401,11 +392,10 @@ INITIALIZE_PASS_BEGIN(RALinScan, "linearscan-regalloc",
 INITIALIZE_PASS_DEPENDENCY(LiveIntervals)
 INITIALIZE_PASS_DEPENDENCY(StrongPHIElimination)
 INITIALIZE_PASS_DEPENDENCY(CalculateSpillWeights)
-INITIALIZE_PASS_DEPENDENCY(PreAllocSplitting)
 INITIALIZE_PASS_DEPENDENCY(LiveStacks)
 INITIALIZE_PASS_DEPENDENCY(MachineLoopInfo)
 INITIALIZE_PASS_DEPENDENCY(VirtRegMap)
-INITIALIZE_AG_DEPENDENCY(RegisterCoalescer)
+INITIALIZE_PASS_DEPENDENCY(RegisterCoalescer)
 INITIALIZE_AG_DEPENDENCY(AliasAnalysis)
 INITIALIZE_PASS_END(RALinScan, "linearscan-regalloc",
                     "Linear Scan Register Allocator", false, false)
@@ -1440,13 +1430,17 @@ unsigned RALinScan::getFreePhysReg(LiveInterval* cur,
   if (TargetRegisterInfo::isVirtualRegister(physReg) && vrm_->hasPhys(physReg))
     physReg = vrm_->getPhys(physReg);
 
-  TargetRegisterClass::iterator I, E;
-  tie(I, E) = tri_->getAllocationOrder(RC, Hint.first, physReg, *mf_);
-  assert(I != E && "No allocatable register in this register class!");
+  ArrayRef<unsigned> Order;
+  if (Hint.first)
+    Order = tri_->getRawAllocationOrder(RC, Hint.first, physReg, *mf_);
+  else
+    Order = RegClassInfo.getOrder(RC);
+
+  assert(!Order.empty() && "No allocatable register in this register class!");
 
   // Scan for the first available register.
-  for (; I != E; ++I) {
-    unsigned Reg = *I;
+  for (unsigned i = 0; i != Order.size(); ++i) {
+    unsigned Reg = Order[i];
     // Ignore "downgraded" registers.
     if (SkipDGRegs && DowngradedRegs.count(Reg))
       continue;
@@ -1476,8 +1470,8 @@ unsigned RALinScan::getFreePhysReg(LiveInterval* cur,
   // inactive count.  Alkis found that this reduced register pressure very
   // slightly on X86 (in rev 1.94 of this file), though this should probably be
   // reevaluated now.
-  for (; I != E; ++I) {
-    unsigned Reg = *I;
+  for (unsigned i = 0; i != Order.size(); ++i) {
+    unsigned Reg = Order[i];
     // Ignore "downgraded" registers.
     if (SkipDGRegs && DowngradedRegs.count(Reg))
       continue;