become more strict about when it's safe to use X86ISD::MOVLPS

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112799 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index 852d339d73569aa1705ffc96d7714dc7886a31f2..7acd8932fc6f2506a4e828e1fb6929bc83f3c688 100644 (file)
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -5082,10 +5082,10 @@ SDValue getMOVLP(SDValue &Op, DebugLoc &dl, SelectionDAG &DAG, bool HasSSE2) {
   SDValue TmpV1 = V1;
   SDValue TmpV2 = V2;
 
-  // Trivial case, when V2 is a load.
-  if (TmpV2.getOpcode() == ISD::BIT_CONVERT)
+  // Trivial case, when V2 comes from a load.
+  if (TmpV2.hasOneUse() && TmpV2.getOpcode() == ISD::BIT_CONVERT)
     TmpV2 = TmpV2.getOperand(0);
-  if (TmpV2.getOpcode() == ISD::SCALAR_TO_VECTOR)
+  if (TmpV2.hasOneUse() && TmpV2.getOpcode() == ISD::SCALAR_TO_VECTOR)
     TmpV2 = TmpV2.getOperand(0);
   if (MayFoldLoad(TmpV2))
     CanFoldLoad = true;
@@ -5095,9 +5095,9 @@ SDValue getMOVLP(SDValue &Op, DebugLoc &dl, SelectionDAG &DAG, bool HasSSE2) {
   //    turns into:
   //  (MOVLPSmr addr:$src1, VR128:$src2)
   // So, recognize this potential and also use MOVLPS or MOVLPD
-  if (TmpV1.getOpcode() == ISD::BIT_CONVERT)
+  if (TmpV1.hasOneUse() && TmpV1.getOpcode() == ISD::BIT_CONVERT)
     TmpV1 = TmpV1.getOperand(0);
-  if (MayFoldLoad(TmpV1))
+  if (MayFoldLoad(TmpV1) && MayFoldIntoStore(Op))
     CanFoldLoad = true;
 
   if (CanFoldLoad) {

diff --git a/lib/Target/X86/X86InstrSSE.td b/lib/Target/X86/X86InstrSSE.td
index 9dfcbc48365f5ad1da32e097cbeac75c31cc8514..5540d0ff90d618cd8003130873e2bc0ff9652089 100644 (file)
--- a/lib/Target/X86/X86InstrSSE.td
+++ b/lib/Target/X86/X86InstrSSE.td
@@ -5829,6 +5829,13 @@ def : Pat<(v4i32 (X86Movss VR128:$src1, VR128:$src2)),
 def : Pat<(v4f32 (X86Movss VR128:$src1, VR128:$src2)),
           (MOVSSrr (v4f32 VR128:$src1),
                    (EXTRACT_SUBREG (v4f32 VR128:$src2), sub_ss))>;
+// FIXME: Instead of a X86Movss there should be a X86Movlps here, the problem
+// is during lowering, where it's not possible to recognize the load fold cause
+// it has two uses through a bitcast. One use disappears at isel time and the
+// fold opportunity reappears.
+def : Pat<(X86Movss VR128:$src1,
+                    (bc_v4i32 (v2i64 (load addr:$src2)))),
+          (MOVLPSrm VR128:$src1, addr:$src2)>;
 
 // Shuffle with MOVSD
 def : Pat<(v2f64 (X86Movsd VR128:$src1, (scalar_to_vector FR64:$src2))),
@@ -5909,9 +5916,6 @@ def : Pat<(v4i32 (X86Movlps VR128:$src1, (load addr:$src2))),
 def : Pat<(X86Movlps VR128:$src1,
                     (bc_v4f32 (v2f64 (scalar_to_vector (loadf64 addr:$src2))))),
           (MOVLPSrm VR128:$src1, addr:$src2)>;
-def : Pat<(X86Movlps VR128:$src1,
-                    (bc_v4i32 (v2i64 (load addr:$src2)))),
-          (MOVLPSrm VR128:$src1, addr:$src2)>;
 
 // Shuffle with MOVLPD
 def : Pat<(v2f64 (X86Movlpd VR128:$src1, (load addr:$src2))),