[llvm-commits] [llvm] r40131 - in /llvm/trunk: include/llvm/CodeGen/LiveVariables.h lib/CodeGen/LiveVariables.cpp lib/CodeGen/SimpleRegisterCoalescing.cpp

[Dan Gohman]

Author: djg
Date: Fri Jul 20 18:17:34 2007
New Revision: 40131

URL: http://llvm.org/viewvc/llvm-project?rev=40131&view=rev
Log:
Don't assume that only Uses can be kills. Defs are marked as kills initially
when there are no uses. This fixes a dangling-pointer bug, where pointers to
deleted instructions were not removed from kills lists. More info here:
http://lists.cs.uiuc.edu/pipermail/llvmdev/2007-July/009749.html

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

Modified: llvm/trunk/include/llvm/CodeGen/LiveVariables.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/CodeGen/LiveVariables.h?rev=40131&r1=40130&r2=40131&view=diff

==============================================================================
--- llvm/trunk/include/llvm/CodeGen/LiveVariables.h (original)
+++ llvm/trunk/include/llvm/CodeGen/LiveVariables.h Fri Jul 20 18:17:34 2007
@@ -229,7 +229,7 @@
     bool Removed = false;
     for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
       MachineOperand &MO = MI->getOperand(i);
-      if (MO.isReg() && MO.isUse() && MO.getReg() == reg) {
+      if (MO.isReg() && MO.isKill() && MO.getReg() == reg) {
         MO.unsetIsKill();
         Removed = true;
         break;

Modified: llvm/trunk/lib/CodeGen/LiveVariables.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/LiveVariables.cpp?rev=40131&r1=40130&r2=40131&view=diff

==============================================================================
--- llvm/trunk/lib/CodeGen/LiveVariables.cpp (original)
+++ llvm/trunk/lib/CodeGen/LiveVariables.cpp Fri Jul 20 18:17:34 2007
@@ -582,15 +582,13 @@
         if (VI.DefInst == OldMI)
           VI.DefInst = NewMI;
       }
-      if (MO.isUse()) {
-        if (MO.isKill()) {
-          MO.unsetIsKill();
-          addVirtualRegisterKilled(Reg, NewMI);
-        }
-        // If this is a kill of the value, update the VI kills list.
-        if (VI.removeKill(OldMI))
-          VI.Kills.push_back(NewMI);   // Yes, there was a kill of it
+      if (MO.isKill()) {
+        MO.unsetIsKill();
+        addVirtualRegisterKilled(Reg, NewMI);
       }
+      // If this is a kill of the value, update the VI kills list.
+      if (VI.removeKill(OldMI))
+        VI.Kills.push_back(NewMI);   // Yes, there was a kill of it
     }
   }
 }

Modified: llvm/trunk/lib/CodeGen/SimpleRegisterCoalescing.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SimpleRegisterCoalescing.cpp?rev=40131&r1=40130&r2=40131&view=diff

==============================================================================
--- llvm/trunk/lib/CodeGen/SimpleRegisterCoalescing.cpp (original)
+++ llvm/trunk/lib/CodeGen/SimpleRegisterCoalescing.cpp Fri Jul 20 18:17:34 2007
@@ -955,7 +955,7 @@
 void SimpleRegisterCoalescing::unsetRegisterKill(MachineInstr *MI, unsigned Reg) {
   for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
     MachineOperand &MO = MI->getOperand(i);
-    if (MO.isReg() && MO.isUse() && MO.isKill() && MO.getReg() &&
+    if (MO.isReg() && MO.isKill() && MO.getReg() &&
         mri_->regsOverlap(rep(MO.getReg()), Reg))
       MO.unsetIsKill();
   }
@@ -979,7 +979,7 @@
 
     for (unsigned i = 0, NumOps = MI->getNumOperands(); i != NumOps; ++i) {
       MachineOperand &MO = MI->getOperand(i);
-      if (MO.isReg() && MO.isUse() && MO.isKill() && MO.getReg() &&
+      if (MO.isReg() && MO.isKill() && MO.getReg() &&
           mri_->regsOverlap(rep(MO.getReg()), Reg)) {
         MO.unsetIsKill();
       }