Add PPC FP rounding instructions fri[mnpz]

These instructions are available on the P5x (and later) and on the A2. They
implement the standard floating-point rounding operations (floor, trunc, etc.).
One caveat: frin (round to nearest) does not implement "ties to even", and so
is only enabled in fast-math mode.

llvm-svn: 178337

llvm/lib/Target/PowerPC/PPCSubtarget.cpp

@@ -39,6 +39,7 @@ PPCSubtarget::PPCSubtarget(const std::string &TT, const std::string &CPU,
   , HasQPX(false)
   , HasFSQRT(false)
   , HasSTFIWX(false)
+  , HasFPRND(false)
   , HasISEL(false)
   , HasPOPCNTD(false)
   , HasLDBRX(false)