commit 5e742a3e1b29104fcadc26286f6daa6c450f87d9
author Nadav Rotem <nadav.rotem@intel.com> Thu Aug 11 16:41:21 2011 +0000
committer Nadav Rotem <nadav.rotem@intel.com> Thu Aug 11 16:41:21 2011 +0000
tree ff212dc32e40b08dbbd2b39b49d0445893577ccb
parent 7eba85eb86e349a3e707dd6ffa52b039fb2c28e0

[AVX] If the data which is going to be saved is already in two XMM registers
(for example, after integer operation), do not pack the registers into a YMM
before saving. Its better to save as two XMM registers.

Before:
                vinsertf128         $1, %xmm3, %ymm0, %ymm3
                vinsertf128         $0, %xmm1, %ymm3, %ymm1
                vmovaps              %ymm1, 416(%rsp)

After:
                vmovaps              %xmm3, 416+16(%rsp)
                vmovaps              %xmm1, 416(%rsp)



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137308 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Target/X86/X86ISelLowering.cpp

diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index be3ecd7..94faae5 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -12589,6 +12589,29 @@
   EVT VT = St->getValue().getValueType();
   EVT StVT = St->getMemoryVT();
   DebugLoc dl = St->getDebugLoc();
+  SDValue StoredVal = St->getOperand(1);
+  const TargetLowering &TLI = DAG.getTargetLoweringInfo();
+
+  // If we are saving a concatination of two XMM registers, perform two stores.
+  if (VT.getSizeInBits() == 256 &&
+    StoredVal.getNode()->getOpcode() == ISD::CONCAT_VECTORS &&
+    StoredVal.getNumOperands() == 2) {
+
+    SDValue Value0 = StoredVal.getOperand(0);
+    SDValue Value1 = StoredVal.getOperand(1);
+
+    SDValue Stride = DAG.getConstant(16, TLI.getPointerTy());
+    SDValue Ptr0 = St->getBasePtr();
+    SDValue Ptr1 = DAG.getNode(ISD::ADD, dl, Ptr0.getValueType(), Ptr0, Stride);
+
+    SDValue Ch0 = DAG.getStore(St->getChain(), dl, Value0, Ptr0,
+                                St->getPointerInfo(), St->isVolatile(),
+                                St->isNonTemporal(), St->getAlignment());
+    SDValue Ch1 = DAG.getStore(St->getChain(), dl, Value1, Ptr1,
+                                St->getPointerInfo(), St->isVolatile(),
+                                St->isNonTemporal(), St->getAlignment());
+    return DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Ch0, Ch1);
+  }
 
   // Optimize trunc store (of multiple scalars) to shuffle and store.
   // First, pack all of the elements in one place. Next, store to memory