X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FCodeGen%2FLiveRangeEdit.cpp;h=7793e96c354096d770d458f166fa370818aadbeb;hb=46abfcf4187432da728cbe452c32143da077e07f;hp=b4ce9aa8c12cc45a0b69550b83f6d0275d40ff62;hpb=e2b83ab056836067e2c86ef22223a4c29fe267ce;p=oota-llvm.git

diff --git a/lib/CodeGen/LiveRangeEdit.cpp b/lib/CodeGen/LiveRangeEdit.cpp
index b4ce9aa8c12..7793e96c354 100644
--- a/lib/CodeGen/LiveRangeEdit.cpp
+++ b/lib/CodeGen/LiveRangeEdit.cpp
@@ -12,16 +12,16 @@
 //===----------------------------------------------------------------------===//
 
 #define DEBUG_TYPE "regalloc"
-#include "VirtRegMap.h"
+#include "llvm/CodeGen/LiveRangeEdit.h"
 #include "llvm/ADT/SetVector.h"
 #include "llvm/ADT/Statistic.h"
 #include "llvm/CodeGen/CalcSpillWeights.h"
 #include "llvm/CodeGen/LiveIntervalAnalysis.h"
-#include "llvm/CodeGen/LiveRangeEdit.h"
 #include "llvm/CodeGen/MachineRegisterInfo.h"
-#include "llvm/Target/TargetInstrInfo.h"
+#include "llvm/CodeGen/VirtRegMap.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/raw_ostream.h"
+#include "llvm/Target/TargetInstrInfo.h"
 
 using namespace llvm;
 
@@ -77,7 +77,7 @@ bool LiveRangeEdit::anyRematerializable(AliasAnalysis *aa) {
 /// OrigIdx are also available with the same value at UseIdx.
 bool LiveRangeEdit::allUsesAvailableAt(const MachineInstr *OrigMI,
                                        SlotIndex OrigIdx,
-                                       SlotIndex UseIdx) {
+                                       SlotIndex UseIdx) const {
   OrigIdx = OrigIdx.getRegSlot(true);
   UseIdx = UseIdx.getRegSlot(true);
   for (unsigned i = 0, e = OrigMI->getNumOperands(); i != e; ++i) {
@@ -87,7 +87,7 @@ bool LiveRangeEdit::allUsesAvailableAt(const MachineInstr *OrigMI,
 
     // We can't remat physreg uses, unless it is a constant.
     if (TargetRegisterInfo::isPhysicalRegister(MO.getReg())) {
-      if (MRI.isConstantPhysReg(MO.getReg(), VRM->getMachineFunction()))
+      if (MRI.isConstantPhysReg(MO.getReg(), *OrigMI->getParent()->getParent()))
         continue;
       return false;
     }
@@ -96,6 +96,13 @@ bool LiveRangeEdit::allUsesAvailableAt(const MachineInstr *OrigMI,
     const VNInfo *OVNI = li.getVNInfoAt(OrigIdx);
     if (!OVNI)
       continue;
+
+    // Don't allow rematerialization immediately after the original def.
+    // It would be incorrect if OrigMI redefines the register.
+    // See PR14098.
+    if (SlotIndex::isSameInstr(OrigIdx, UseIdx))
+      return false;
+
     if (OVNI != li.getVNInfoAt(UseIdx))
       return false;
   }
@@ -249,7 +256,7 @@ void LiveRangeEdit::eliminateDeadDefs(SmallVectorImpl<MachineInstr*> &Dead,
         unsigned Reg = MOI->getReg();
         if (!TargetRegisterInfo::isVirtualRegister(Reg)) {
           // Check if MI reads any unreserved physregs.
-          if (Reg && MOI->readsReg() && !LIS.isReserved(Reg))
+          if (Reg && MOI->readsReg() && !MRI.isReserved(Reg))
             ReadsPhysRegs = true;
           continue;
         }