[CostModel][X86] Add funnel shift rotation special case costs

When we repeat the 2 shifting operands then this is a bit rotation - annoyingly this has to be done in the other getIntrinsicInstrCost than most intrinsics as we need to check the operands are the same.

llvm-svn: 346688

1 files changed, 82 insertions, 1 deletions

diff --git a/llvm/lib/Target/X86/X86TargetTransformInfo.cpp b/llvm/lib/Target/X86/X86TargetTransformInfo.cpp
index 6e25e701f3f..05bfbe51f96 100644
--- a/llvm/lib/Target/X86/X86TargetTransformInfo.cpp
+++ b/llvm/lib/Target/X86/X86TargetTransformInfo.cpp
@@ -1953,7 +1953,88 @@ int X86TTIImpl::getIntrinsicInstrCost(Intrinsic::ID IID, Type *RetTy,
 }
 
 int X86TTIImpl::getIntrinsicInstrCost(Intrinsic::ID IID, Type *RetTy,
-                     ArrayRef<Value *> Args, FastMathFlags FMF, unsigned VF) {
+                                      ArrayRef<Value *> Args, FastMathFlags FMF,
+                                      unsigned VF) {
+  static const CostTblEntry AVX512CostTbl[] = {
+    { ISD::ROTL,       MVT::v8i64,   1 },
+    { ISD::ROTL,       MVT::v4i64,   1 },
+    { ISD::ROTL,       MVT::v2i64,   1 },
+    { ISD::ROTL,       MVT::v16i32,  1 },
+    { ISD::ROTL,       MVT::v8i32,   1 },
+    { ISD::ROTL,       MVT::v4i32,   1 },
+    { ISD::ROTR,       MVT::v8i64,   1 },
+    { ISD::ROTR,       MVT::v4i64,   1 },
+    { ISD::ROTR,       MVT::v2i64,   1 },
+    { ISD::ROTR,       MVT::v16i32,  1 },
+    { ISD::ROTR,       MVT::v8i32,   1 },
+    { ISD::ROTR,       MVT::v4i32,   1 }
+  };
+  // XOP: ROTL = VPROT(X,Y), ROTR = VPROT(SUB(0,X),Y)
+  static const CostTblEntry XOPCostTbl[] = {
+    { ISD::ROTL,       MVT::v4i64,   4 },
+    { ISD::ROTL,       MVT::v8i32,   4 },
+    { ISD::ROTL,       MVT::v16i16,  4 },
+    { ISD::ROTL,       MVT::v32i8,   4 },
+    { ISD::ROTL,       MVT::v2i64,   1 },
+    { ISD::ROTL,       MVT::v4i32,   1 },
+    { ISD::ROTL,       MVT::v8i16,   1 },
+    { ISD::ROTL,       MVT::v16i8,   1 },
+    { ISD::ROTR,       MVT::v4i64,   6 },
+    { ISD::ROTR,       MVT::v8i32,   6 },
+    { ISD::ROTR,       MVT::v16i16,  6 },
+    { ISD::ROTR,       MVT::v32i8,   6 },
+    { ISD::ROTR,       MVT::v2i64,   2 },
+    { ISD::ROTR,       MVT::v4i32,   2 },
+    { ISD::ROTR,       MVT::v8i16,   2 },
+    { ISD::ROTR,       MVT::v16i8,   2 }
+  };
+  static const CostTblEntry X64CostTbl[] = { // 64-bit targets
+    { ISD::ROTL,       MVT::i64,     1 },
+    { ISD::ROTR,       MVT::i64,     1 }
+  };
+  static const CostTblEntry X86CostTbl[] = { // 32 or 64-bit targets
+    { ISD::ROTL,       MVT::i32,     1 },
+    { ISD::ROTL,       MVT::i16,     1 },
+    { ISD::ROTL,       MVT::i8,      1 },
+    { ISD::ROTR,       MVT::i32,     1 },
+    { ISD::ROTR,       MVT::i16,     1 },
+    { ISD::ROTR,       MVT::i8,      1 }
+  };
+
+  unsigned ISD = ISD::DELETED_NODE;
+  switch (IID) {
+  default:
+    break;
+  case Intrinsic::fshl:
+    if (Args[0] == Args[1])
+      ISD = ISD::ROTL;
+    break;
+  case Intrinsic::fshr:
+    if (Args[0] == Args[1])
+      ISD = ISD::ROTR;
+    break;
+  }
+
+  // Legalize the type.
+  std::pair<int, MVT> LT = TLI->getTypeLegalizationCost(DL, RetTy);
+  MVT MTy = LT.second;
+
+  // Attempt to lookup cost.
+  if (ST->hasAVX512())
+    if (const auto *Entry = CostTableLookup(AVX512CostTbl, ISD, MTy))
+      return LT.first * Entry->Cost;
+
+  if (ST->hasXOP())
+    if (const auto *Entry = CostTableLookup(XOPCostTbl, ISD, MTy))
+      return LT.first * Entry->Cost;
+
+  if (ST->is64Bit())
+    if (const auto *Entry = CostTableLookup(X64CostTbl, ISD, MTy))
+      return LT.first * Entry->Cost;
+
+  if (const auto *Entry = CostTableLookup(X86CostTbl, ISD, MTy))
+    return LT.first * Entry->Cost;
+
   return BaseT::getIntrinsicInstrCost(IID, RetTy, Args, FMF, VF);
 }