From: Alkis Evlogimenos <alkis@evlogimenos.com>
Date: Wed, 24 Dec 2003 15:44:53 +0000 (+0000)
Subject: Do a separate pass to compute spill weights because doing it inline
X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=7a40eaaceec0af76d5b97610f3d4e7a47a19d245;p=oota-llvm.git

Do a separate pass to compute spill weights because doing it inline
with live intervals was missing registers that were used before they
were defined (in the arbitrary order live intervals numbers
instructions).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10603 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/CodeGen/LiveIntervalAnalysis.cpp b/lib/CodeGen/LiveIntervalAnalysis.cpp
index e4b134bc9d5..b34a65bc644 100644
--- a/lib/CodeGen/LiveIntervalAnalysis.cpp
+++ b/lib/CodeGen/LiveIntervalAnalysis.cpp
@@ -106,6 +106,33 @@ bool LiveIntervals::runOnMachineFunction(MachineFunction &fn) {
 
     computeIntervals();
 
+    // compute spill weights
+    const LoopInfo& loopInfo = getAnalysis<LoopInfo>();
+
+    for (MbbIndex2MbbMap::iterator
+             it = mbbi2mbbMap_.begin(), itEnd = mbbi2mbbMap_.end();
+         it != itEnd; ++it) {
+        MachineBasicBlock* mbb = it->second;
+
+        unsigned loopDepth = loopInfo.getLoopDepth(mbb->getBasicBlock());
+
+        for (MachineBasicBlock::iterator mi = mbb->begin(), miEnd = mbb->end();
+             mi != miEnd; ++mi) {
+            MachineInstr* instr = *mi;
+            for (int i = instr->getNumOperands() - 1; i >= 0; --i) {
+                MachineOperand& mop = instr->getOperand(i);
+
+                if (!mop.isVirtualRegister())
+                    continue;
+
+                unsigned reg = mop.getAllocatedRegNum();
+                Reg2IntervalMap::iterator r2iit = r2iMap_.find(reg);
+                assert(r2iit != r2iMap_.end());
+                intervals_[r2iit->second].weight += pow(10.0F, loopDepth);
+            }
+        }
+    }
+
     return true;
 }
 
@@ -255,8 +282,6 @@ void LiveIntervals::computeIntervals()
 {
     DEBUG(std::cerr << "computing live intervals:\n");
 
-    const LoopInfo& loopInfo = getAnalysis<LoopInfo>();
-
     for (MbbIndex2MbbMap::iterator
              it = mbbi2mbbMap_.begin(), itEnd = mbbi2mbbMap_.end();
          it != itEnd; ++it) {
@@ -264,8 +289,6 @@ void LiveIntervals::computeIntervals()
         DEBUG(std::cerr << "machine basic block: "
               << mbb->getBasicBlock()->getName() << "\n");
 
-        unsigned loopDepth = loopInfo.getLoopDepth(mbb->getBasicBlock());
-
         for (MachineBasicBlock::iterator mi = mbb->begin(), miEnd = mbb->end();
              mi != miEnd; ++mi) {
             MachineInstr* instr = *mi;
@@ -296,12 +319,6 @@ void LiveIntervals::computeIntervals()
                     else
                         handleVirtualRegisterDef(mbb, mi, reg);
                 }
-
-                // update weights
-                Reg2IntervalMap::iterator r2iit = r2iMap_.find(reg);
-                if (r2iit != r2iMap_.end() &&
-                    reg >= MRegisterInfo::FirstVirtualRegister)
-                    intervals_[r2iit->second].weight += pow(10.0F, loopDepth);
             }
         }
     }