CalculateSpillWeights does not need to be a pass

Based on discussions with Lang Hames and Jakob Stoklund Olesen at the hacker's lab, and in the light of upcoming work on the PBQP register allocator, it was though that CalcSpillWeights does not need to be a pass. This change will enable to customize / tune the spill weight computation depending on the allocator.

Update the documentation style while there.

No functionnal change.

llvm-svn: 194269

1 files changed, 5 insertions, 22 deletions

diff --git a/llvm/lib/CodeGen/CalcSpillWeights.cpp b/llvm/lib/CodeGen/CalcSpillWeights.cpp
index 67a8755cf06..d02ee03adbd 100644
--- a/llvm/lib/CodeGen/CalcSpillWeights.cpp
+++ b/llvm/lib/CodeGen/CalcSpillWeights.cpp
@@ -22,38 +22,21 @@
 #include "llvm/Target/TargetRegisterInfo.h"
 using namespace llvm;
 
-char CalculateSpillWeights::ID = 0;
-INITIALIZE_PASS_BEGIN(CalculateSpillWeights, "calcspillweights",
-                "Calculate spill weights", false, false)
-INITIALIZE_PASS_DEPENDENCY(LiveIntervals)
-INITIALIZE_PASS_DEPENDENCY(MachineLoopInfo)
-INITIALIZE_PASS_END(CalculateSpillWeights, "calcspillweights",
-                "Calculate spill weights", false, false)
-
-void CalculateSpillWeights::getAnalysisUsage(AnalysisUsage &au) const {
-  au.addRequired<LiveIntervals>();
-  au.addRequired<MachineBlockFrequencyInfo>();
-  au.addRequired<MachineLoopInfo>();
-  au.setPreservesAll();
-  MachineFunctionPass::getAnalysisUsage(au);
-}
-
-bool CalculateSpillWeights::runOnMachineFunction(MachineFunction &MF) {
-
+void llvm::calculateSpillWeights(LiveIntervals &LIS,
+                           MachineFunction &MF,
+                           const MachineLoopInfo &MLI,
+                           const MachineBlockFrequencyInfo &MBFI) {
   DEBUG(dbgs() << "********** Compute Spill Weights **********\n"
                << "********** Function: " << MF.getName() << '\n');
 
-  LiveIntervals &LIS = getAnalysis<LiveIntervals>();
   MachineRegisterInfo &MRI = MF.getRegInfo();
-  VirtRegAuxInfo VRAI(MF, LIS, getAnalysis<MachineLoopInfo>(),
-                      getAnalysis<MachineBlockFrequencyInfo>());
+  VirtRegAuxInfo VRAI(MF, LIS, MLI, MBFI);
   for (unsigned i = 0, e = MRI.getNumVirtRegs(); i != e; ++i) {
     unsigned Reg = TargetRegisterInfo::index2VirtReg(i);
     if (MRI.reg_nodbg_empty(Reg))
       continue;
     VRAI.CalculateWeightAndHint(LIS.getInterval(Reg));
   }
-  return false;
 }
 
 // Return the preferred allocation register for reg, given a COPY instruction.