MachineBasicBlock: Add liveins() method returning an iterator_range

llvm-svn: 245895
diff --git a/llvm/lib/Target/X86/X86FloatingPoint.cpp b/llvm/lib/Target/X86/X86FloatingPoint.cpp
index 36a8cdb..a6a0184 100644
--- a/llvm/lib/Target/X86/X86FloatingPoint.cpp
+++ b/llvm/lib/Target/X86/X86FloatingPoint.cpp
@@ -120,12 +120,10 @@
     // Return a bitmask of FP registers in block's live-in list.
     static unsigned calcLiveInMask(MachineBasicBlock *MBB) {
       unsigned Mask = 0;
-      for (MachineBasicBlock::livein_iterator I = MBB->livein_begin(),
-           E = MBB->livein_end(); I != E; ++I) {
-        unsigned Reg = *I;
-        if (Reg < X86::FP0 || Reg > X86::FP6)
+      for (unsigned LI : MBB->liveins()) {
+        if (LI < X86::FP0 || LI > X86::FP6)
           continue;
-        Mask |= 1 << (Reg - X86::FP0);
+        Mask |= 1 << (LI - X86::FP0);
       }
       return Mask;
     }