Handle more cases in LiveRangeEdit::eliminateDeadDefs.

Live intervals for dead physregs may be created during coalescing. We
need to update these in the event that their instruction goes away.

crash.ll is the unit test that catches it when MI sched is enabled on
X86.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@184572 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/llvm/CodeGen/MachineRegisterInfo.h b/include/llvm/CodeGen/MachineRegisterInfo.h
index 95c1ffd..7a6dcd0 100644 (file)
--- a/include/llvm/CodeGen/MachineRegisterInfo.h
+++ b/include/llvm/CodeGen/MachineRegisterInfo.h
@@ -58,10 +58,6 @@ class MachineRegisterInfo {
   /// physical registers.
   MachineOperand **PhysRegUseDefLists;
 
-  const TargetRegisterInfo *getTargetRegisterInfo() const {
-    return TM.getRegisterInfo();
-  }
-
   /// getRegUseDefListHead - Return the head pointer for the register use/def
   /// list for the specified virtual or physical register.
   MachineOperand *&getRegUseDefListHead(unsigned RegNo) {
@@ -116,6 +112,10 @@ public:
   explicit MachineRegisterInfo(const TargetMachine &TM);
   ~MachineRegisterInfo();
 
+  const TargetRegisterInfo *getTargetRegisterInfo() const {
+    return TM.getRegisterInfo();
+  }
+
   //===--------------------------------------------------------------------===//
   // Function State
   //===--------------------------------------------------------------------===//

diff --git a/lib/CodeGen/LiveRangeEdit.cpp b/lib/CodeGen/LiveRangeEdit.cpp
index 0c1d459..d215d0c 100644 (file)
--- a/lib/CodeGen/LiveRangeEdit.cpp
+++ b/lib/CodeGen/LiveRangeEdit.cpp
@@ -249,6 +249,15 @@ void LiveRangeEdit::eliminateDeadDef(MachineInstr *MI, ToShrinkSet &ToShrink) {
       // Check if MI reads any unreserved physregs.
       if (Reg && MOI->readsReg() && !MRI.isReserved(Reg))
         ReadsPhysRegs = true;
+      else if (MOI->isDef()) {
+        for (MCRegUnitIterator Units(Reg, MRI.getTargetRegisterInfo());
+             Units.isValid(); ++Units) {
+          if (LiveInterval *LI = LIS.getCachedRegUnit(*Units)) {
+            if (VNInfo *VNI = LI->getVNInfoAt(Idx))
+              LI->removeValNo(VNI);
+          }
+        }
+      }
       continue;
     }
     LiveInterval &LI = LIS.getInterval(Reg);