[CostModel][X86] Add explicit fcmp costs for pre-SSE42 targets

Typical throughputs: cmpss/cmpps = 1cy and cmpsd/cmppd = 2cy before the Core2 era

llvm-svn: 351684

1 files changed, 11 insertions, 0 deletions

diff --git a/llvm/lib/Target/X86/X86TargetTransformInfo.cpp b/llvm/lib/Target/X86/X86TargetTransformInfo.cpp
index 443007969eb..1d94eed2372 100644
--- a/llvm/lib/Target/X86/X86TargetTransformInfo.cpp
+++ b/llvm/lib/Target/X86/X86TargetTransformInfo.cpp
@@ -1686,12 +1686,19 @@ int X86TTIImpl::getCmpSelInstrCost(unsigned Opcode, Type *ValTy, Type *CondTy,
   };
 
   static const CostTblEntry SSE2CostTbl[] = {
+    { ISD::SETCC,   MVT::v2f64,   2 },
+    { ISD::SETCC,   MVT::f64,     1 },
     { ISD::SETCC,   MVT::v2i64,   8 },
     { ISD::SETCC,   MVT::v4i32,   1 },
     { ISD::SETCC,   MVT::v8i16,   1 },
     { ISD::SETCC,   MVT::v16i8,   1 },
   };
 
+  static const CostTblEntry SSE1CostTbl[] = {
+    { ISD::SETCC,   MVT::v4f32,   2 },
+    { ISD::SETCC,   MVT::f32,     1 },
+  };
+
   if (ST->hasBWI())
     if (const auto *Entry = CostTableLookup(AVX512BWCostTbl, ISD, MTy))
       return LT.first * Entry->Cost;
@@ -1716,6 +1723,10 @@ int X86TTIImpl::getCmpSelInstrCost(unsigned Opcode, Type *ValTy, Type *CondTy,
     if (const auto *Entry = CostTableLookup(SSE2CostTbl, ISD, MTy))
       return LT.first * Entry->Cost;
 
+  if (ST->hasSSE1())
+    if (const auto *Entry = CostTableLookup(SSE1CostTbl, ISD, MTy))
+      return LT.first * Entry->Cost;
+
   return BaseT::getCmpSelInstrCost(Opcode, ValTy, CondTy, I);
 }