Use MRI::getSimpleHint() instead of getRegAllocPref() in remaining ca…

…ses.

Targets can provide multiple hints now, so getRegAllocPref() doesn't
make sense any longer because it only returns one preferred register.
Replace it with getSimpleHint() in the remaining heuristics. This
function only

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169188 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/CodeGen/VirtRegMap.h

@@ -130,9 +130,7 @@ namespace llvm {
     unsigned getRegAllocPref(unsigned virtReg);
 
     /// @brief returns true if VirtReg is assigned to its preferred physreg.
-    bool hasPreferredPhys(unsigned VirtReg) {
-      return getPhys(VirtReg) == getRegAllocPref(VirtReg);
-    }
+    bool hasPreferredPhys(unsigned VirtReg);
 
     /// @brief returns true if VirtReg has a known preferred register.
     /// This returns false if VirtReg has a preference that is a virtual

lib/CodeGen/RegAllocPBQP.cpp

@@ -526,7 +526,7 @@ void RegAllocPBQP::finalizeAlloc() const {
          itr != end; ++itr) {
     LiveInterval *li = &lis->getInterval(*itr);
 
-    unsigned physReg = vrm->getRegAllocPref(li->reg);
+    unsigned physReg = mri->getSimpleHint(li->reg);
 
     if (physReg == 0) {
       const TargetRegisterClass *liRC = mri->getRegClass(li->reg);

lib/CodeGen/VirtRegMap.cpp

@@ -88,6 +88,15 @@ unsigned VirtRegMap::getRegAllocPref(unsigned virtReg) {
   return TRI->ResolveRegAllocHint(Hint.first, physReg, *MF);
 }
 
+bool VirtRegMap::hasPreferredPhys(unsigned VirtReg) {
+  unsigned Hint = MRI->getSimpleHint(VirtReg);
+  if (!Hint)
+    return 0;
+  if (TargetRegisterInfo::isVirtualRegister(Hint))
+    Hint = getPhys(Hint);
+  return getPhys(VirtReg) == Hint;
+}
+
 bool VirtRegMap::hasKnownPreference(unsigned VirtReg) {
   std::pair<unsigned, unsigned> Hint = MRI->getRegAllocationHint(VirtReg);
   if (TargetRegisterInfo::isPhysicalRegister(Hint.second))