X86TTI: Adjust sdiv cost now that we can lower it on plain SSE2.

Includes a fix for a horrible typo that caused all SDIV costs to be
slightly off :)

llvm-svn: 207371

1 files changed, 5 insertions, 0 deletions

diff --git a/llvm/lib/Target/X86/X86TargetTransformInfo.cpp b/llvm/lib/Target/X86/X86TargetTransformInfo.cpp
index 628e9130a15..1543f109b4c 100644
--- a/llvm/lib/Target/X86/X86TargetTransformInfo.cpp
+++ b/llvm/lib/Target/X86/X86TargetTransformInfo.cpp
@@ -369,11 +369,16 @@ unsigned X86TTI::getArithmeticInstrCost(unsigned Opcode, Type *Ty,
 
     { ISD::SDIV, MVT::v8i16,  6 }, // pmulhw sequence
     { ISD::UDIV, MVT::v8i16,  6 }, // pmulhuw sequence
+    { ISD::SDIV, MVT::v4i32, 19 }, // pmuludq sequence
     { ISD::UDIV, MVT::v4i32, 15 }, // pmuludq sequence
   };
 
   if (Op2Info == TargetTransformInfo::OK_UniformConstantValue &&
       ST->hasSSE2()) {
+    // pmuldq sequence.
+    if (ISD == ISD::SDIV && LT.second == MVT::v4i32 && ST->hasSSE41())
+      return LT.first * 15;
+
     int Idx = CostTableLookup(SSE2UniformConstCostTable, ISD, LT.second);
     if (Idx != -1)
       return LT.first * SSE2UniformConstCostTable[Idx].Cost;