Special cases are needed in renumbering when dealing with renumbering after a PHI...

by the PHI needs to be extended to the beginning of its basic block, and the intervals that were inputs need to be trimmed to the end
of their basic blocks.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54070 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/LiveIntervalAnalysis.cpp b/lib/CodeGen/LiveIntervalAnalysis.cpp
index 833cb95eb9f3029a37657dbf78bea0f7f9377602..169143d63aeacc14d8bcb149982e4c55074c8f38 100644 (file)
--- a/lib/CodeGen/LiveIntervalAnalysis.cpp
+++ b/lib/CodeGen/LiveIntervalAnalysis.cpp
@@ -126,6 +126,7 @@ void LiveIntervals::computeNumbering() {
     MBB2IdxMap[MBB->getNumber()] = std::make_pair(StartIdx, MIIndex - 1);
     Idx2MBBMap.push_back(std::make_pair(StartIdx, MBB));
   }
+  
   std::sort(Idx2MBBMap.begin(), Idx2MBBMap.end(), Idx2MBBCompare());
   
   if (!OldI2MI.empty())
@@ -139,7 +140,7 @@ void LiveIntervals::computeNumbering() {
         // instruction or its predecessor.
         unsigned index = LI->start / InstrSlots::NUM;
         unsigned offset = LI->start % InstrSlots::NUM;
-        if (offset == InstrSlots::LOAD) {
+        if (offset == InstrSlots::LOAD || LI->valno->def == ~0U) {
           std::vector<IdxMBBPair>::const_iterator I =
                   std::lower_bound(OldI2MBB.begin(), OldI2MBB.end(), LI->start);
           // Take the pair containing the index
@@ -157,7 +158,30 @@ void LiveIntervals::computeNumbering() {
         // following instruction.
         index = (LI->end - 1) / InstrSlots::NUM;
         offset  = LI->end % InstrSlots::NUM;
-        if (offset == InstrSlots::USE) {
+        if (LI->valno->hasPHIKill && !OldI2MI[index]) {
+          // Special handling for when this was previously killed by a PHI, but
+          // the PHI has now been removed.  We need to trim the live interval
+          // to die at the end of the preceding block.
+          std::vector<IdxMBBPair>::const_iterator I =
+                  std::lower_bound(OldI2MBB.begin(), OldI2MBB.end(), LI->end);
+          // Take the pair containing the index
+          std::vector<IdxMBBPair>::const_iterator J =
+                    ((I != OldI2MBB.end() && I->first > index) ||
+                    (I == OldI2MBB.end() && OldI2MBB.size()>0)) ? (I-1): I;
+          
+          MachineBasicBlock* StartMBB = J->second;
+          MachineBasicBlock* CurrMBB = J->second;
+          
+          while (CurrMBB == StartMBB) {
+            while (index > 0 && !OldI2MI[index]) --index;
+            CurrMBB = OldI2MI[index]->getParent();
+            if (!StartMBB) StartMBB = CurrMBB;
+            
+            --index;
+          }
+          
+          LI->end = getMBBEndIdx(CurrMBB) + 1;
+        } else if (offset == InstrSlots::USE) {
           std::vector<IdxMBBPair>::const_iterator I =
                   std::lower_bound(OldI2MBB.begin(), OldI2MBB.end(), LI->end);
           // Take the pair containing the index
@@ -179,20 +203,23 @@ void LiveIntervals::computeNumbering() {
         // Remap the VNInfo def index, which works the same as the
         // start indices above.
         VNInfo* vni = LI->valno;
-        index = vni->def / InstrSlots::NUM;
-        offset = vni->def % InstrSlots::NUM;
-        if (offset == InstrSlots::LOAD) {
-          std::vector<IdxMBBPair>::const_iterator I =
-                  std::lower_bound(OldI2MBB.begin(), OldI2MBB.end(), vni->def);
-          // Take the pair containing the index
-          std::vector<IdxMBBPair>::const_iterator J =
-                    ((I != OldI2MBB.end() && I->first > index) ||
-                    (I == OldI2MBB.end() && OldI2MBB.size()>0)) ? (I-1): I;
+        if (vni->def != ~0U) {
+          index = vni->def / InstrSlots::NUM;
+          offset = vni->def % InstrSlots::NUM;
+          if (offset == InstrSlots::LOAD) {
+            std::vector<IdxMBBPair>::const_iterator I =
+                    std::lower_bound(OldI2MBB.begin(), OldI2MBB.end(), 
+                                     vni->def);
+            // Take the pair containing the index
+            std::vector<IdxMBBPair>::const_iterator J =
+                      ((I != OldI2MBB.end() && I->first > index) ||
+                      (I == OldI2MBB.end() && OldI2MBB.size()>0)) ? (I-1): I;
           
-          vni->def = getMBBStartIdx(J->second);
+            vni->def = getMBBStartIdx(J->second);
           
-        } else {
-          vni->def = mi2iMap_[OldI2MI[index]] + offset;
+          } else {
+            vni->def = mi2iMap_[OldI2MI[index]] + offset;
+          }
         }
         
         // Remap the VNInfo kill indices, which works the same as
@@ -200,7 +227,31 @@ void LiveIntervals::computeNumbering() {
         for (size_t i = 0; i < vni->kills.size(); ++i) {
           index = (vni->kills[i]-1) / InstrSlots::NUM;
           offset = vni->kills[i] % InstrSlots::NUM;
-          if (offset == InstrSlots::USE) {
+          
+          if (LI->valno->hasPHIKill && !OldI2MI[index]) {
+            // Special handling for when this was previously killed by a PHI,
+            // but the PHI has now been removed.  We need to trim the live
+            // interval to die at the end of the preceding block.
+            std::vector<IdxMBBPair>::const_iterator I =
+                    std::lower_bound(OldI2MBB.begin(), OldI2MBB.end(), LI->end);
+            // Take the pair containing the index
+            std::vector<IdxMBBPair>::const_iterator J =
+                      ((I != OldI2MBB.end() && I->first > index) ||
+                      (I == OldI2MBB.end() && OldI2MBB.size()>0)) ? (I-1): I;
+
+            MachineBasicBlock* StartMBB = J->second;
+            MachineBasicBlock* CurrMBB = J->second;
+
+            while (CurrMBB == StartMBB) {
+              while (index > 0 && !OldI2MI[index]) --index;
+              CurrMBB = OldI2MI[index]->getParent();
+              if (!StartMBB) StartMBB = CurrMBB;
+
+              --index;
+            }
+
+            vni->kills[i] = getMBBEndIdx(CurrMBB) + 1;
+          } else if (offset == InstrSlots::USE) {
             std::vector<IdxMBBPair>::const_iterator I =
              std::lower_bound(OldI2MBB.begin(), OldI2MBB.end(), vni->kills[i]);
             // Take the pair containing the index