R600/SI: Implement getOptimalMemOpType

The default guess uses i32. This needs an address space argument
to really do the right thing in all cases.

llvm-svn: 214104

2 files changed, 26 insertions, 0 deletions

diff --git a/llvm/lib/Target/R600/SIISelLowering.cpp b/llvm/lib/Target/R600/SIISelLowering.cpp
index a4d4195edde..c3405e10453 100644
--- a/llvm/lib/Target/R600/SIISelLowering.cpp
+++ b/llvm/lib/Target/R600/SIISelLowering.cpp
@@ -274,6 +274,26 @@ bool SITargetLowering::allowsMisalignedMemoryAccesses(EVT  VT,
   return VT.bitsGT(MVT::i32);
 }
 
+EVT SITargetLowering::getOptimalMemOpType(uint64_t Size, unsigned DstAlign,
+                                          unsigned SrcAlign, bool IsMemset,
+                                          bool ZeroMemset,
+                                          bool MemcpyStrSrc,
+                                          MachineFunction &MF) const {
+  // FIXME: Should account for address space here.
+
+  // The default fallback uses the private pointer size as a guess for a type to
+  // use. Make sure we switch these to 64-bit accesses.
+
+  if (Size >= 16 && DstAlign >= 4) // XXX: Should only do for global
+    return MVT::v4i32;
+
+  if (Size >= 8 && DstAlign >= 4)
+    return MVT::v2i32;
+
+  // Use the default.
+  return MVT::Other;
+}
+
 TargetLoweringBase::LegalizeTypeAction
 SITargetLowering::getPreferredVectorAction(EVT VT) const {
   if (VT.getVectorNumElements() != 1 && VT.getScalarType().bitsLE(MVT::i16))
diff --git a/llvm/lib/Target/R600/SIISelLowering.h b/llvm/lib/Target/R600/SIISelLowering.h
index d03bc864148..93e97c32357 100644
--- a/llvm/lib/Target/R600/SIISelLowering.h
+++ b/llvm/lib/Target/R600/SIISelLowering.h
@@ -63,6 +63,12 @@ public:
                                       unsigned Align,
                                       bool *IsFast) const override;
 
+  EVT getOptimalMemOpType(uint64_t Size, unsigned DstAlign,
+                          unsigned SrcAlign, bool IsMemset,
+                          bool ZeroMemset,
+                          bool MemcpyStrSrc,
+                          MachineFunction &MF) const override;
+
   TargetLoweringBase::LegalizeTypeAction
   getPreferredVectorAction(EVT VT) const override;