[llvm-commits] [llvm] r126924 - in /llvm/trunk: include/llvm/CodeGen/SlotIndexes.h lib/CodeGen/RegAllocLinearScan.cpp lib/CodeGen/SimpleRegisterCoalescing.cpp

[Jakob Stoklund Olesen]

Author: stoklund
Date: Wed Mar  2 23:18:19 2011
New Revision: 126924

URL: http://llvm.org/viewvc/llvm-project?rev=126924&view=rev
Log:
Avoid comparing invalid slot indexes, and assert that it doesn't happen.

The SlotIndex created by the default construction does not represent a position
in the function, and it doesn't make sense to compare it to other indexes.

Modified:
    llvm/trunk/include/llvm/CodeGen/SlotIndexes.h
    llvm/trunk/lib/CodeGen/RegAllocLinearScan.cpp
    llvm/trunk/lib/CodeGen/SimpleRegisterCoalescing.cpp

Modified: llvm/trunk/include/llvm/CodeGen/SlotIndexes.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/CodeGen/SlotIndexes.h?rev=126924&r1=126923&r2=126924&view=diff
==============================================================================
--- llvm/trunk/include/llvm/CodeGen/SlotIndexes.h (original)
+++ llvm/trunk/include/llvm/CodeGen/SlotIndexes.h Wed Mar  2 23:18:19 2011
@@ -135,6 +135,7 @@
     }
 
     IndexListEntry& entry() const {
+      assert(isValid() && "Attempt to compare reserved index.");
       return *lie.getPointer();
     }
 
@@ -530,7 +531,7 @@
     /// Returns the instruction for the given index, or null if the given
     /// index has no instruction associated with it.
     MachineInstr* getInstructionFromIndex(SlotIndex index) const {
-      return index.entry().getInstr();
+      return index.isValid() ? index.entry().getInstr() : 0;
     }
 
     /// Returns the next non-null index.

Modified: llvm/trunk/lib/CodeGen/RegAllocLinearScan.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/RegAllocLinearScan.cpp?rev=126924&r1=126923&r2=126924&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/RegAllocLinearScan.cpp (original)
+++ llvm/trunk/lib/CodeGen/RegAllocLinearScan.cpp Wed Mar  2 23:18:19 2011
@@ -458,7 +458,7 @@
   const LiveRange &range = cur.ranges.front();
 
   VNInfo *vni = range.valno;
-  if (vni->isUnused())
+  if (vni->isUnused() || !vni->def.isValid())
     return Reg;
 
   unsigned CandReg;
@@ -993,7 +993,7 @@
   // one, e.g. X86::mov32to32_. These move instructions are not coalescable.
   if (!vrm_->getRegAllocPref(cur->reg) && cur->hasAtLeastOneValue()) {
     VNInfo *vni = cur->begin()->valno;
-    if (!vni->isUnused()) {
+    if (!vni->isUnused() && vni->def.isValid()) {
       MachineInstr *CopyMI = li_->getInstructionFromIndex(vni->def);
       if (CopyMI && CopyMI->isCopy()) {
         unsigned DstSubReg = CopyMI->getOperand(0).getSubReg();

Modified: llvm/trunk/lib/CodeGen/SimpleRegisterCoalescing.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SimpleRegisterCoalescing.cpp?rev=126924&r1=126923&r2=126924&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/SimpleRegisterCoalescing.cpp (original)
+++ llvm/trunk/lib/CodeGen/SimpleRegisterCoalescing.cpp Wed Mar  2 23:18:19 2011
@@ -1568,9 +1568,7 @@
       if (UseMI->isIdentityCopy())
         continue;
       SlotIndex Idx = li_->getInstructionIndex(UseMI);
-      // FIXME: Should this be Idx != UseIdx? SlotIndex() will return something
-      // that compares higher than any other interval.
-      if (Idx >= Start && Idx < End && Idx >= UseIdx) {
+      if (Idx >= Start && Idx < End && (!UseIdx.isValid() || Idx >= UseIdx)) {
         LastUse = &Use;
         UseIdx = Idx.getUseIndex();
       }