Improve the X86 cost model for loads and stores.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170830 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 28 insertions, 0 deletions

diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index 1e64741c25..6b650726b6 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -17818,6 +17818,30 @@ X86VectorTargetTransformInfo::getArithmeticInstrCost(unsigned Opcode,
   return VectorTargetTransformImpl::getArithmeticInstrCost(Opcode, Ty);
 }
 
+
+unsigned
+X86VectorTargetTransformInfo::getMemoryOpCost(unsigned Opcode, Type *Src,
+                                              unsigned Alignment,
+                                              unsigned AddressSpace) const {
+  // Legalize the type.
+  std::pair<unsigned, MVT> LT = getTypeLegalizationCost(Src);
+  assert(Opcode == Instruction::Load || Opcode == Instruction::Store &&
+         "Invalid Opcode");
+
+  const X86Subtarget &ST =
+  TLI->getTargetMachine().getSubtarget<X86Subtarget>();
+
+  // Each load/store unit costs 1.
+  unsigned Cost = LT.first * 1;
+
+  // On Sandybridge 256bit load/stores are double pumped
+  // (but not on Haswell).
+  if (LT.second.getSizeInBits() > 128 && !ST.hasAVX2())
+    Cost*=2;
+
+  return Cost;
+}
+
 unsigned
 X86VectorTargetTransformInfo::getVectorInstrCost(unsigned Opcode, Type *Val,
                                                  unsigned Index) const {
diff --git a/lib/Target/X86/X86ISelLowering.h b/lib/Target/X86/X86ISelLowering.h
index 5be7f095a4..72cd3b3f5b 100644
--- a/lib/Target/X86/X86ISelLowering.h
+++ b/lib/Target/X86/X86ISelLowering.h
@@ -953,6 +953,10 @@ namespace llvm {
 
     virtual unsigned getArithmeticInstrCost(unsigned Opcode, Type *Ty) const;
 
+    virtual unsigned getMemoryOpCost(unsigned Opcode, Type *Src,
+                                     unsigned Alignment,
+                                     unsigned AddressSpace) const;
+
     virtual unsigned getVectorInstrCost(unsigned Opcode, Type *Val,
                                         unsigned Index) const;