Convert cost table lookup functions to return a pointer to the entry or nullptr inste...

This avoid mentioning the table name an extra time and allows the lookup to be done directly in the ifs by relying on the bool conversion of the pointer.

While there make use of ArrayRef and std::find_if.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251382 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/llvm/Target/CostTable.h b/include/llvm/Target/CostTable.h
index 34f6041137c12635a870f64b66bb93a1201e1ad2..489435fb1c04c2f415dc77aa45c186273402330c 100644 (file)
--- a/include/llvm/Target/CostTable.h
+++ b/include/llvm/Target/CostTable.h
@@ -15,6 +15,8 @@
 #ifndef LLVM_TARGET_COSTTABLE_H_
 #define LLVM_TARGET_COSTTABLE_H_
 
+#include "llvm/ADT/ArrayRef.h"
+
 namespace llvm {
 
 /// Cost Table Entry
@@ -27,21 +29,23 @@ struct CostTblEntry {
 
 /// Find in cost table, TypeTy must be comparable to CompareTy by ==
 template <class TypeTy, class CompareTy>
-int CostTableLookup(const CostTblEntry<TypeTy> *Tbl, unsigned len, int ISD,
-                    CompareTy Ty) {
-  for (unsigned int i = 0; i < len; ++i)
-    if (ISD == Tbl[i].ISD && Ty == Tbl[i].Type)
-      return i;
+const CostTblEntry<TypeTy> *CostTableLookup(ArrayRef<CostTblEntry<TypeTy>> Tbl,
+                                            int ISD, CompareTy Ty) {
+  auto I = std::find_if(Tbl.begin(), Tbl.end(),
+                        [=](const CostTblEntry<TypeTy> &Entry) {
+                          return ISD == Entry.ISD && Ty == Entry.Type; });
+  if (I != Tbl.end())
+    return I;
 
   // Could not find an entry.
-  return -1;
+  return nullptr;
 }
 
 /// Find in cost table, TypeTy must be comparable to CompareTy by ==
 template <class TypeTy, class CompareTy, unsigned N>
-int CostTableLookup(const CostTblEntry<TypeTy>(&Tbl)[N], int ISD,
-                    CompareTy Ty) {
-  return CostTableLookup(Tbl, N, ISD, Ty);
+const CostTblEntry<TypeTy> *CostTableLookup(const CostTblEntry<TypeTy>(&Tbl)[N],
+                                            int ISD, CompareTy Ty) {
+  return CostTableLookup(makeArrayRef(Tbl), ISD, Ty);
 }
 
 /// Type Conversion Cost Table
@@ -56,23 +60,28 @@ struct TypeConversionCostTblEntry {
 /// Find in type conversion cost table, TypeTy must be comparable to CompareTy
 /// by ==
 template <class TypeTy, class CompareTy>
-int ConvertCostTableLookup(const TypeConversionCostTblEntry<TypeTy> *Tbl,
-                           unsigned len, int ISD, CompareTy Dst,
-                           CompareTy Src) {
-  for (unsigned int i = 0; i < len; ++i)
-    if (ISD == Tbl[i].ISD && Src == Tbl[i].Src && Dst == Tbl[i].Dst)
-      return i;
+const TypeConversionCostTblEntry<TypeTy> *
+ConvertCostTableLookup(ArrayRef<TypeConversionCostTblEntry<TypeTy>> Tbl,
+                       int ISD, CompareTy Dst, CompareTy Src) {
+  auto I = std::find_if(Tbl.begin(), Tbl.end(),
+                        [=](const TypeConversionCostTblEntry<TypeTy> &Entry) {
+                          return ISD == Entry.ISD && Src == Entry.Src &&
+                                 Dst == Entry.Dst;
+                        });
+  if (I != Tbl.end())
+    return I;
 
   // Could not find an entry.
-  return -1;
+  return nullptr;
 }
 
 /// Find in type conversion cost table, TypeTy must be comparable to CompareTy
 /// by ==
 template <class TypeTy, class CompareTy, unsigned N>
-int ConvertCostTableLookup(const TypeConversionCostTblEntry<TypeTy>(&Tbl)[N],
-                           int ISD, CompareTy Dst, CompareTy Src) {
-  return ConvertCostTableLookup(Tbl, N, ISD, Dst, Src);
+const TypeConversionCostTblEntry<TypeTy> *
+ConvertCostTableLookup(const TypeConversionCostTblEntry<TypeTy>(&Tbl)[N],
+                       int ISD, CompareTy Dst, CompareTy Src) {
+  return ConvertCostTableLookup(makeArrayRef(Tbl), ISD, Dst, Src);
 }
 
 } // namespace llvm

diff --git a/lib/Target/AArch64/AArch64TargetTransformInfo.cpp b/lib/Target/AArch64/AArch64TargetTransformInfo.cpp
index 024e05b501a28bff3724d5afa5c10dd86fd04721..813f53581a70fd746a48825fe812b3d18507ef78 100644 (file)
--- a/lib/Target/AArch64/AArch64TargetTransformInfo.cpp
+++ b/lib/Target/AArch64/AArch64TargetTransformInfo.cpp
@@ -282,10 +282,10 @@ int AArch64TTIImpl::getCastInstrCost(unsigned Opcode, Type *Dst, Type *Src) {
     { ISD::FP_TO_UINT, MVT::v2i8,  MVT::v2f64, 2 },
   };
 
-  int Idx = ConvertCostTableLookup(ConversionTbl, ISD, DstTy.getSimpleVT(),
-                                   SrcTy.getSimpleVT());
-  if (Idx != -1)
-    return ConversionTbl[Idx].Cost;
+  if (const auto *Entry = ConvertCostTableLookup(ConversionTbl, ISD,
+                                                 DstTy.getSimpleVT(),
+                                                 SrcTy.getSimpleVT()))
+    return Entry->Cost;
 
   return BaseT::getCastInstrCost(Opcode, Dst, Src);
 }
@@ -398,11 +398,10 @@ int AArch64TTIImpl::getCmpSelInstrCost(unsigned Opcode, Type *ValTy,
     EVT SelCondTy = TLI->getValueType(DL, CondTy);
     EVT SelValTy = TLI->getValueType(DL, ValTy);
     if (SelCondTy.isSimple() && SelValTy.isSimple()) {
-      int Idx =
-          ConvertCostTableLookup(VectorSelectTbl, ISD, SelCondTy.getSimpleVT(),
-                                 SelValTy.getSimpleVT());
-      if (Idx != -1)
-        return VectorSelectTbl[Idx].Cost;
+      if (const auto *Entry = ConvertCostTableLookup(VectorSelectTbl, ISD,
+                                                     SelCondTy.getSimpleVT(),
+                                                     SelValTy.getSimpleVT()))
+        return Entry->Cost;
     }
   }
   return BaseT::getCmpSelInstrCost(Opcode, ValTy, CondTy);

diff --git a/lib/Target/ARM/ARMTargetTransformInfo.cpp b/lib/Target/ARM/ARMTargetTransformInfo.cpp
index 51ece526a6e55518b381399016032a017945bd93..0bb5b180a891bbfb43ed08d93f3637faf8242ae6 100644 (file)
--- a/lib/Target/ARM/ARMTargetTransformInfo.cpp
+++ b/lib/Target/ARM/ARMTargetTransformInfo.cpp
@@ -62,9 +62,8 @@ int ARMTTIImpl::getCastInstrCost(unsigned Opcode, Type *Dst, Type *Src) {
   if (Src->isVectorTy() && ST->hasNEON() && (ISD == ISD::FP_ROUND ||
                                           ISD == ISD::FP_EXTEND)) {
     std::pair<int, MVT> LT = TLI->getTypeLegalizationCost(DL, Src);
-    int Idx = CostTableLookup(NEONFltDblTbl, ISD, LT.second);
-    if (Idx != -1)
-      return LT.first * NEONFltDblTbl[Idx].Cost;
+    if (const auto *Entry = CostTableLookup(NEONFltDblTbl, ISD, LT.second))
+      return LT.first * Entry->Cost;
   }
 
   EVT SrcTy = TLI->getValueType(DL, Src);
@@ -153,10 +152,10 @@ int ARMTTIImpl::getCastInstrCost(unsigned Opcode, Type *Dst, Type *Src) {
   };
 
   if (SrcTy.isVector() && ST->hasNEON()) {
-    int Idx = ConvertCostTableLookup(NEONVectorConversionTbl, ISD,
-                                     DstTy.getSimpleVT(), SrcTy.getSimpleVT());
-    if (Idx != -1)
-      return NEONVectorConversionTbl[Idx].Cost;
+    if (const auto *Entry = ConvertCostTableLookup(NEONVectorConversionTbl, ISD,
+                                                   DstTy.getSimpleVT(),
+                                                   SrcTy.getSimpleVT()))
+      return Entry->Cost;
   }
 
   // Scalar float to integer conversions.
@@ -184,10 +183,10 @@ int ARMTTIImpl::getCastInstrCost(unsigned Opcode, Type *Dst, Type *Src) {
     { ISD::FP_TO_UINT,  MVT::i64, MVT::f64, 10 }
   };
   if (SrcTy.isFloatingPoint() && ST->hasNEON()) {
-    int Idx = ConvertCostTableLookup(NEONFloatConversionTbl, ISD,
-                                     DstTy.getSimpleVT(), SrcTy.getSimpleVT());
-    if (Idx != -1)
-        return NEONFloatConversionTbl[Idx].Cost;
+    if (const auto *Entry = ConvertCostTableLookup(NEONFloatConversionTbl, ISD,
+                                                   DstTy.getSimpleVT(),
+                                                   SrcTy.getSimpleVT()))
+      return Entry->Cost;
   }
 
   // Scalar integer to float conversions.
@@ -216,10 +215,10 @@ int ARMTTIImpl::getCastInstrCost(unsigned Opcode, Type *Dst, Type *Src) {
   };
 
   if (SrcTy.isInteger() && ST->hasNEON()) {
-    int Idx = ConvertCostTableLookup(NEONIntegerConversionTbl, ISD,
-                                     DstTy.getSimpleVT(), SrcTy.getSimpleVT());
-    if (Idx != -1)
-      return NEONIntegerConversionTbl[Idx].Cost;
+    if (const auto *Entry = ConvertCostTableLookup(NEONIntegerConversionTbl,
+                                                   ISD, DstTy.getSimpleVT(),
+                                                   SrcTy.getSimpleVT()))
+      return Entry->Cost;
   }
 
   // Scalar integer conversion costs.
@@ -236,10 +235,10 @@ int ARMTTIImpl::getCastInstrCost(unsigned Opcode, Type *Dst, Type *Src) {
   };
 
   if (SrcTy.isInteger()) {
-    int Idx = ConvertCostTableLookup(ARMIntegerConversionTbl, ISD,
-                                     DstTy.getSimpleVT(), SrcTy.getSimpleVT());
-    if (Idx != -1)
-      return ARMIntegerConversionTbl[Idx].Cost;
+    if (const auto *Entry = ConvertCostTableLookup(ARMIntegerConversionTbl, ISD,
+                                                   DstTy.getSimpleVT(),
+                                                   SrcTy.getSimpleVT()))
+      return Entry->Cost;
   }
 
   return BaseT::getCastInstrCost(Opcode, Dst, Src);
@@ -291,11 +290,10 @@ int ARMTTIImpl::getCmpSelInstrCost(unsigned Opcode, Type *ValTy, Type *CondTy) {
     EVT SelCondTy = TLI->getValueType(DL, CondTy);
     EVT SelValTy = TLI->getValueType(DL, ValTy);
     if (SelCondTy.isSimple() && SelValTy.isSimple()) {
-      int Idx = ConvertCostTableLookup(NEONVectorSelectTbl, ISD,
-                                       SelCondTy.getSimpleVT(),
-                                       SelValTy.getSimpleVT());
-      if (Idx != -1)
-        return NEONVectorSelectTbl[Idx].Cost;
+      if (const auto *Entry = ConvertCostTableLookup(NEONVectorSelectTbl, ISD,
+                                                     SelCondTy.getSimpleVT(),
+                                                     SelValTy.getSimpleVT()))
+        return Entry->Cost;
     }
 
     std::pair<int, MVT> LT = TLI->getTypeLegalizationCost(DL, ValTy);
@@ -361,11 +359,11 @@ int ARMTTIImpl::getShuffleCost(TTI::ShuffleKind Kind, Type *Tp, int Index,
 
     std::pair<int, MVT> LT = TLI->getTypeLegalizationCost(DL, Tp);
 
-    int Idx = CostTableLookup(NEONShuffleTbl, ISD::VECTOR_SHUFFLE, LT.second);
-    if (Idx == -1)
-      return BaseT::getShuffleCost(Kind, Tp, Index, SubTp);
+    if (const auto *Entry = CostTableLookup(NEONShuffleTbl, ISD::VECTOR_SHUFFLE,
+                                            LT.second))
+      return LT.first * Entry->Cost;
 
-    return LT.first * NEONShuffleTbl[Idx].Cost;
+    return BaseT::getShuffleCost(Kind, Tp, Index, SubTp);
   }
   if (Kind == TTI::SK_Alternate) {
     static const CostTblEntry<MVT::SimpleValueType> NEONAltShuffleTbl[] = {
@@ -386,11 +384,10 @@ int ARMTTIImpl::getShuffleCost(TTI::ShuffleKind Kind, Type *Tp, int Index,
         {ISD::VECTOR_SHUFFLE, MVT::v16i8, 32}};
 
     std::pair<int, MVT> LT = TLI->getTypeLegalizationCost(DL, Tp);
-    int Idx =
-        CostTableLookup(NEONAltShuffleTbl, ISD::VECTOR_SHUFFLE, LT.second);
-    if (Idx == -1)
-      return BaseT::getShuffleCost(Kind, Tp, Index, SubTp);
-    return LT.first * NEONAltShuffleTbl[Idx].Cost;
+    if (const auto *Entry = CostTableLookup(NEONAltShuffleTbl,
+                                            ISD::VECTOR_SHUFFLE, LT.second))
+      return LT.first * Entry->Cost;
+    return BaseT::getShuffleCost(Kind, Tp, Index, SubTp);
   }
   return BaseT::getShuffleCost(Kind, Tp, Index, SubTp);
 }
@@ -446,13 +443,9 @@ int ARMTTIImpl::getArithmeticInstrCost(
     // Multiplication.
   };
 
-  int Idx = -1;
-
   if (ST->hasNEON())
-    Idx = CostTableLookup(CostTbl, ISDOpcode, LT.second);
-
-  if (Idx != -1)
-    return LT.first * CostTbl[Idx].Cost;
+    if (const auto *Entry = CostTableLookup(CostTbl, ISDOpcode, LT.second))
+      return LT.first * Entry->Cost;
 
   int Cost = BaseT::getArithmeticInstrCost(Opcode, Ty, Op1Info, Op2Info,
                                            Opd1PropInfo, Opd2PropInfo);

diff --git a/lib/Target/X86/X86TargetTransformInfo.cpp b/lib/Target/X86/X86TargetTransformInfo.cpp
index 1b825df4c87360fcd69a420958d582d295ea5920..69b541f2d5df609a25fc5d1a6993fa63946deddb 100644 (file)
--- a/lib/Target/X86/X86TargetTransformInfo.cpp
+++ b/lib/Target/X86/X86TargetTransformInfo.cpp
@@ -127,9 +127,9 @@ int X86TTIImpl::getArithmeticInstrCost(
 
   if (Op2Info == TargetTransformInfo::OK_UniformConstantValue &&
       ST->hasAVX2()) {
-    int Idx = CostTableLookup(AVX2UniformConstCostTable, ISD, LT.second);
-    if (Idx != -1)
-      return LT.first * AVX2UniformConstCostTable[Idx].Cost;
+    if (const auto *Entry = CostTableLookup(AVX2UniformConstCostTable, ISD,
+                                            LT.second))
+      return LT.first * Entry->Cost;
   }
 
   static const CostTblEntry<MVT::SimpleValueType> AVX512CostTable[] = {
@@ -142,9 +142,8 @@ int X86TTIImpl::getArithmeticInstrCost(
   };
 
   if (ST->hasAVX512()) {
-    int Idx = CostTableLookup(AVX512CostTable, ISD, LT.second);
-    if (Idx != -1)
-      return LT.first * AVX512CostTable[Idx].Cost;
+    if (const auto *Entry = CostTableLookup(AVX512CostTable, ISD, LT.second))
+      return LT.first * Entry->Cost;
   }
 
   static const CostTblEntry<MVT::SimpleValueType> AVX2CostTable[] = {
@@ -171,9 +170,8 @@ int X86TTIImpl::getArithmeticInstrCost(
       // is lowered into a vector multiply (vpmullw).
       return LT.first;
 
-    int Idx = CostTableLookup(AVX2CostTable, ISD, LT.second);
-    if (Idx != -1)
-      return LT.first * AVX2CostTable[Idx].Cost;
+    if (const auto *Entry = CostTableLookup(AVX2CostTable, ISD, LT.second))
+      return LT.first * Entry->Cost;
   }
 
   static const CostTblEntry<MVT::SimpleValueType> XOPCostTable[] = {
@@ -207,9 +205,8 @@ int X86TTIImpl::getArithmeticInstrCost(
 
   // Look for XOP lowering tricks.
   if (ST->hasXOP()) {
-    int Idx = CostTableLookup(XOPCostTable, ISD, LT.second);
-    if (Idx != -1)
-      return LT.first * XOPCostTable[Idx].Cost;
+    if (const auto *Entry = CostTableLookup(XOPCostTable, ISD, LT.second))
+      return LT.first * Entry->Cost;
   }
 
   static const CostTblEntry<MVT::SimpleValueType> AVX2CustomCostTable[] = {
@@ -237,9 +234,9 @@ int X86TTIImpl::getArithmeticInstrCost(
 
   // Look for AVX2 lowering tricks for custom cases.
   if (ST->hasAVX2()) {
-    int Idx = CostTableLookup(AVX2CustomCostTable, ISD, LT.second);
-    if (Idx != -1)
-      return LT.first * AVX2CustomCostTable[Idx].Cost;
+    if (const auto *Entry = CostTableLookup(AVX2CustomCostTable, ISD,
+                                            LT.second))
+      return LT.first * Entry->Cost;
   }
 
   static const CostTblEntry<MVT::SimpleValueType>
@@ -286,9 +283,9 @@ int X86TTIImpl::getArithmeticInstrCost(
     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;
+    if (const auto *Entry = CostTableLookup(SSE2UniformConstCostTable, ISD,
+                                            LT.second))
+      return LT.first * Entry->Cost;
   }
 
   if (ISD == ISD::SHL &&
@@ -366,9 +363,8 @@ int X86TTIImpl::getArithmeticInstrCost(
   };
 
   if (ST->hasSSE2()) {
-    int Idx = CostTableLookup(SSE2CostTable, ISD, LT.second);
-    if (Idx != -1)
-      return LT.first * SSE2CostTable[Idx].Cost;
+    if (const auto *Entry = CostTableLookup(SSE2CostTable, ISD, LT.second))
+      return LT.first * Entry->Cost;
   }
 
   static const CostTblEntry<MVT::SimpleValueType> AVX1CostTable[] = {
@@ -393,9 +389,8 @@ int X86TTIImpl::getArithmeticInstrCost(
   if (ST->hasAVX() && !ST->hasAVX2()) {
     MVT VT = LT.second;
 
-    int Idx = CostTableLookup(AVX1CostTable, ISD, VT);
-    if (Idx != -1)
-      return LT.first * AVX1CostTable[Idx].Cost;
+    if (const auto *Entry = CostTableLookup(AVX1CostTable, ISD, VT))
+      return LT.first * Entry->Cost;
   }
 
   // Custom lowering of vectors.
@@ -405,9 +400,8 @@ int X86TTIImpl::getArithmeticInstrCost(
     { ISD::MUL,     MVT::v2i64,    9 },
     { ISD::MUL,     MVT::v4i64,    9 },
   };
-  int Idx = CostTableLookup(CustomLowered, ISD, LT.second);
-  if (Idx != -1)
-    return LT.first * CustomLowered[Idx].Cost;
+  if (const auto *Entry = CostTableLookup(CustomLowered, ISD, LT.second))
+    return LT.first * Entry->Cost;
 
   // Special lowering of v4i32 mul on sse2, sse3: Lower v4i32 mul as 2x shuffle,
   // 2x pmuludq, 2x shuffle.
@@ -461,11 +455,10 @@ int X86TTIImpl::getShuffleCost(TTI::ShuffleKind Kind, Type *Tp, int Index,
       {ISD::VECTOR_SHUFFLE, MVT::v32i8, 9}
     };
 
-    if (ST->hasAVX()) {
-      int Idx = CostTableLookup(AVXAltShuffleTbl, ISD::VECTOR_SHUFFLE, LT.second);
-      if (Idx != -1)
-        return LT.first * AVXAltShuffleTbl[Idx].Cost;
-    }
+    if (ST->hasAVX())
+      if (const auto *Entry = CostTableLookup(AVXAltShuffleTbl,
+                                              ISD::VECTOR_SHUFFLE, LT.second))
+        return LT.first * Entry->Cost;
 
     static const CostTblEntry<MVT::SimpleValueType> SSE41AltShuffleTbl[] = {
       // These are lowered into movsd.
@@ -485,11 +478,10 @@ int X86TTIImpl::getShuffleCost(TTI::ShuffleKind Kind, Type *Tp, int Index,
       {ISD::VECTOR_SHUFFLE, MVT::v16i8, 3}
     };
 
-    if (ST->hasSSE41()) {
-      int Idx = CostTableLookup(SSE41AltShuffleTbl, ISD::VECTOR_SHUFFLE, LT.second);
-      if (Idx != -1)
-        return LT.first * SSE41AltShuffleTbl[Idx].Cost;
-    }
+    if (ST->hasSSE41())
+      if (const auto *Entry = CostTableLookup(SSE41AltShuffleTbl, ISD::VECTOR_SHUFFLE,
+                                              LT.second))
+        return LT.first * Entry->Cost;
 
     static const CostTblEntry<MVT::SimpleValueType> SSSE3AltShuffleTbl[] = {
       {ISD::VECTOR_SHUFFLE, MVT::v2i64, 1},  // movsd
@@ -504,11 +496,10 @@ int X86TTIImpl::getShuffleCost(TTI::ShuffleKind Kind, Type *Tp, int Index,
       {ISD::VECTOR_SHUFFLE, MVT::v16i8, 3}  // pshufb + pshufb + or
     };
 
-    if (ST->hasSSSE3()) {
-      int Idx = CostTableLookup(SSSE3AltShuffleTbl, ISD::VECTOR_SHUFFLE, LT.second);
-      if (Idx != -1)
-        return LT.first * SSSE3AltShuffleTbl[Idx].Cost;
-    }
+    if (ST->hasSSSE3())
+      if (const auto *Entry = CostTableLookup(SSSE3AltShuffleTbl,
+                                              ISD::VECTOR_SHUFFLE, LT.second))
+        return LT.first * Entry->Cost;
 
     static const CostTblEntry<MVT::SimpleValueType> SSEAltShuffleTbl[] = {
       {ISD::VECTOR_SHUFFLE, MVT::v2i64, 1},  // movsd
@@ -525,9 +516,9 @@ int X86TTIImpl::getShuffleCost(TTI::ShuffleKind Kind, Type *Tp, int Index,
     };
 
     // Fall-back (SSE3 and SSE2).
-    int Idx = CostTableLookup(SSEAltShuffleTbl, ISD::VECTOR_SHUFFLE, LT.second);
-    if (Idx != -1)
-      return LT.first * SSEAltShuffleTbl[Idx].Cost;
+    if (const auto *Entry = CostTableLookup(SSEAltShuffleTbl,
+                                            ISD::VECTOR_SHUFFLE, LT.second))
+      return LT.first * Entry->Cost;
     return BaseT::getShuffleCost(Kind, Tp, Index, SubTp);
   }
 
@@ -702,17 +693,15 @@ int X86TTIImpl::getCastInstrCost(unsigned Opcode, Type *Dst, Type *Src) {
   std::pair<int, MVT> LTDest = TLI->getTypeLegalizationCost(DL, Dst);
 
   if (ST->hasSSE2() && !ST->hasAVX()) {
-    int Idx =
-        ConvertCostTableLookup(SSE2ConvTbl, ISD, LTDest.second, LTSrc.second);
-    if (Idx != -1)
-      return LTSrc.first * SSE2ConvTbl[Idx].Cost;
+    if (const auto *Entry = ConvertCostTableLookup(SSE2ConvTbl, ISD,
+                                                   LTDest.second, LTSrc.second))
+      return LTSrc.first * Entry->Cost;
   }
 
   if (ST->hasAVX512()) {
-    int Idx = ConvertCostTableLookup(AVX512ConversionTbl, ISD, LTDest.second,
-                                     LTSrc.second);
-    if (Idx != -1)
-      return AVX512ConversionTbl[Idx].Cost;
+    if (const auto *Entry = ConvertCostTableLookup(AVX512ConversionTbl, ISD,
+                                                   LTDest.second, LTSrc.second))
+      return Entry->Cost;
   }
 
   EVT SrcTy = TLI->getValueType(DL, Src);
@@ -723,17 +712,17 @@ int X86TTIImpl::getCastInstrCost(unsigned Opcode, Type *Dst, Type *Src) {
     return BaseT::getCastInstrCost(Opcode, Dst, Src);
 
   if (ST->hasAVX2()) {
-    int Idx = ConvertCostTableLookup(AVX2ConversionTbl, ISD,
-                                     DstTy.getSimpleVT(), SrcTy.getSimpleVT());
-    if (Idx != -1)
-      return AVX2ConversionTbl[Idx].Cost;
+    if (const auto *Entry = ConvertCostTableLookup(AVX2ConversionTbl, ISD,
+                                                   DstTy.getSimpleVT(),
+                                                   SrcTy.getSimpleVT()))
+      return Entry->Cost;
   }
 
   if (ST->hasAVX()) {
-    int Idx = ConvertCostTableLookup(AVXConversionTbl, ISD, DstTy.getSimpleVT(),
-                                     SrcTy.getSimpleVT());
-    if (Idx != -1)
-      return AVXConversionTbl[Idx].Cost;
+    if (const auto *Entry = ConvertCostTableLookup(AVXConversionTbl, ISD,
+                                                   DstTy.getSimpleVT(),
+                                                   SrcTy.getSimpleVT()))
+      return Entry->Cost;
   }
 
   return BaseT::getCastInstrCost(Opcode, Dst, Src);
@@ -781,29 +770,21 @@ int X86TTIImpl::getCmpSelInstrCost(unsigned Opcode, Type *ValTy, Type *CondTy) {
     { ISD::SETCC,   MVT::v16f32,  1 },
   };
 
-  if (ST->hasAVX512()) {
-    int Idx = CostTableLookup(AVX512CostTbl, ISD, MTy);
-    if (Idx != -1)
-      return LT.first * AVX512CostTbl[Idx].Cost;
-  }
+  if (ST->hasAVX512())
+    if (const auto *Entry = CostTableLookup(AVX512CostTbl, ISD, MTy))
+      return LT.first * Entry->Cost;
 
-  if (ST->hasAVX2()) {
-    int Idx = CostTableLookup(AVX2CostTbl, ISD, MTy);
-    if (Idx != -1)
-      return LT.first * AVX2CostTbl[Idx].Cost;
-  }
+  if (ST->hasAVX2())
+    if (const auto *Entry = CostTableLookup(AVX2CostTbl, ISD, MTy))
+      return LT.first * Entry->Cost;
 
-  if (ST->hasAVX()) {
-    int Idx = CostTableLookup(AVX1CostTbl, ISD, MTy);
-    if (Idx != -1)
-      return LT.first * AVX1CostTbl[Idx].Cost;
-  }
+  if (ST->hasAVX())
+    if (const auto *Entry = CostTableLookup(AVX1CostTbl, ISD, MTy))
+      return LT.first * Entry->Cost;
 
-  if (ST->hasSSE42()) {
-    int Idx = CostTableLookup(SSE42CostTbl, ISD, MTy);
-    if (Idx != -1)
-      return LT.first * SSE42CostTbl[Idx].Cost;
-  }
+  if (ST->hasSSE42())
+    if (const auto *Entry = CostTableLookup(SSE42CostTbl, ISD, MTy))
+      return LT.first * Entry->Cost;
 
   return BaseT::getCmpSelInstrCost(Opcode, ValTy, CondTy);
 }
@@ -1004,29 +985,21 @@ int X86TTIImpl::getReductionCost(unsigned Opcode, Type *ValTy,
   };
 
   if (IsPairwise) {
-    if (ST->hasAVX()) {
-      int Idx = CostTableLookup(AVX1CostTblPairWise, ISD, MTy);
-      if (Idx != -1)
-        return LT.first * AVX1CostTblPairWise[Idx].Cost;
-    }
+    if (ST->hasAVX())
+      if (const auto *Entry = CostTableLookup(AVX1CostTblPairWise, ISD, MTy))
+        return LT.first * Entry->Cost;
 
-    if (ST->hasSSE42()) {
-      int Idx = CostTableLookup(SSE42CostTblPairWise, ISD, MTy);
-      if (Idx != -1)
-        return LT.first * SSE42CostTblPairWise[Idx].Cost;
-    }
+    if (ST->hasSSE42())
+      if (const auto *Entry = CostTableLookup(SSE42CostTblPairWise, ISD, MTy))
+        return LT.first * Entry->Cost;
   } else {
-    if (ST->hasAVX()) {
-      int Idx = CostTableLookup(AVX1CostTblNoPairWise, ISD, MTy);
-      if (Idx != -1)
-        return LT.first * AVX1CostTblNoPairWise[Idx].Cost;
-    }
+    if (ST->hasAVX())
+      if (const auto *Entry = CostTableLookup(AVX1CostTblNoPairWise, ISD, MTy))
+        return LT.first * Entry->Cost;
 
-    if (ST->hasSSE42()) {
-      int Idx = CostTableLookup(SSE42CostTblNoPairWise, ISD, MTy);
-      if (Idx != -1)
-        return LT.first * SSE42CostTblNoPairWise[Idx].Cost;
-    }
+    if (ST->hasSSE42())
+      if (const auto *Entry = CostTableLookup(SSE42CostTblNoPairWise, ISD, MTy))
+        return LT.first * Entry->Cost;
   }
 
   return BaseT::getReductionCost(Opcode, ValTy, IsPairwise);