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

1 files changed, 17 insertions, 0 deletions

diff --git a/llvm/lib/Target/PowerPC/PPCISelLowering.cpp b/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
index 74e811b35cf..84af0bbb31b 100644
--- a/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
+++ b/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
@@ -158,6 +158,23 @@ PPCTargetLowering::PPCTargetLowering(PPCTargetMachine &TM)
   setOperationAction(ISD::FCOPYSIGN, MVT::f64, Expand);
   setOperationAction(ISD::FCOPYSIGN, MVT::f32, Expand);
 
+  if (Subtarget->hasFPRND()) {
+    setOperationAction(ISD::FFLOOR, MVT::f64, Legal);
+    setOperationAction(ISD::FCEIL,  MVT::f64, Legal);
+    setOperationAction(ISD::FTRUNC, MVT::f64, Legal);
+
+    setOperationAction(ISD::FFLOOR, MVT::f32, Legal);
+    setOperationAction(ISD::FCEIL,  MVT::f32, Legal);
+    setOperationAction(ISD::FTRUNC, MVT::f32, Legal);
+
+    // frin does not implement "ties to even." Thus, this is safe only in
+    // fast-math mode.
+    if (TM.Options.UnsafeFPMath) {
+      setOperationAction(ISD::FNEARBYINT, MVT::f64, Legal);
+      setOperationAction(ISD::FNEARBYINT, MVT::f32, Legal);
+    }
+  }
+
   // PowerPC does not have BSWAP, CTPOP or CTTZ
   setOperationAction(ISD::BSWAP, MVT::i32  , Expand);
   setOperationAction(ISD::CTTZ , MVT::i32  , Expand);