Revert. This wasn't meant to be checked in.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@31737 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86FloatingPoint.cpp b/lib/Target/X86/X86FloatingPoint.cpp
index c0e46b2..0b4a19b 100644
--- a/lib/Target/X86/X86FloatingPoint.cpp
+++ b/lib/Target/X86/X86FloatingPoint.cpp
@@ -40,7 +40,6 @@
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/Compiler.h"
 #include "llvm/ADT/DepthFirstIterator.h"
-#include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/Statistic.h"
 #include "llvm/ADT/STLExtras.h"
 #include <algorithm>
@@ -214,12 +213,20 @@
 
     // Get dead variables list now because the MI pointer may be deleted as part
     // of processing!
-    SmallVector<unsigned, 8> DeadRegs;
-    for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
-      const MachineOperand &MO = MI->getOperand(i);
-      if (MO.isReg() && MO.isDead())
-        DeadRegs.push_back(MO.getReg());
-    }
+    LiveVariables::killed_iterator IB, IE;
+    tie(IB, IE) = LV->dead_range(MI);
+
+    DEBUG(
+      const MRegisterInfo *MRI = MF.getTarget().getRegisterInfo();
+      LiveVariables::killed_iterator I = LV->killed_begin(MI);
+      LiveVariables::killed_iterator E = LV->killed_end(MI);
+      if (I != E) {
+        std::cerr << "Killed Operands:";
+        for (; I != E; ++I)
+          std::cerr << " %" << MRI->getName(*I);
+        std::cerr << "\n";
+      }
+    );
 
     switch (Flags & X86II::FPTypeMask) {
     case X86II::ZeroArgFP:  handleZeroArgFP(I); break;
@@ -234,8 +241,8 @@
 
     // Check to see if any of the values defined by this instruction are dead
     // after definition.  If so, pop them.
-    for (unsigned i = 0, e = DeadRegs.size(); i != e; ++i) {
-      unsigned Reg = DeadRegs[i];
+    for (; IB != IE; ++IB) {
+      unsigned Reg = *IB;
       if (Reg >= X86::FP0 && Reg <= X86::FP6) {
         DEBUG(std::cerr << "Register FP#" << Reg-X86::FP0 << " is dead!\n");
         freeStackSlotAfter(I, Reg-X86::FP0);
@@ -755,7 +762,6 @@
 
   unsigned Op0 = getFPReg(MI->getOperand(0));
   unsigned Op1 = getFPReg(MI->getOperand(2));
-  bool KillsOp1 = LV->KillsRegister(MI, X86::FP0+Op1);
 
   // The first operand *must* be on the top of the stack.
   moveToTop(Op0, I);
@@ -767,8 +773,9 @@
   MI->getOperand(0).setReg(getSTReg(Op1));
   MI->setOpcode(getConcreteOpcode(MI->getOpcode()));
   
+  
   // If we kill the second operand, make sure to pop it from the stack.
-  if (Op0 != Op1 && KillsOp1) {
+  if (Op0 != Op1 && LV->KillsRegister(MI, X86::FP0+Op1)) {
     // Get this value off of the register stack.
     freeStackSlotAfter(I, Op1);
   }