1 files changed, 88 insertions, 0 deletions

diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index a39e453dd2..464c5bcb53 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -9402,6 +9402,8 @@ const char *X86TargetLowering::getTargetNodeName(unsigned Opcode) const {
   case X86ISD::UCOMI:              return "X86ISD::UCOMI";
   case X86ISD::SETCC:              return "X86ISD::SETCC";
   case X86ISD::SETCC_CARRY:        return "X86ISD::SETCC_CARRY";
+  case X86ISD::FSETCCsd:           return "X86ISD::FSETCCsd";
+  case X86ISD::FSETCCss:           return "X86ISD::FSETCCss";
   case X86ISD::CMOV:               return "X86ISD::CMOV";
   case X86ISD::BRCOND:             return "X86ISD::BRCOND";
   case X86ISD::RET_FLAG:           return "X86ISD::RET_FLAG";
@@ -11679,12 +11681,94 @@ static SDValue PerformShiftCombine(SDNode* N, SelectionDAG &DAG,
 }
 
 
+// CMPEQCombine - Recognize the distinctive  (AND (setcc ...) (setcc ..))
+// where both setccs reference the same FP CMP, and rewrite for CMPEQSS
+// and friends.  Likewise for OR -> CMPNEQSS.
+static SDValue CMPEQCombine(SDNode *N, SelectionDAG &DAG,
+                            TargetLowering::DAGCombinerInfo &DCI,
+                            const X86Subtarget *Subtarget) {
+  unsigned opcode;
+
+  // SSE1 supports CMP{eq|ne}SS, and SSE2 added CMP{eq|ne}SD, but
+  // we're requiring SSE2 for both.
+  if (Subtarget->hasSSE2() && isAndOrOfSetCCs(SDValue(N, 0U), opcode)) {
+    SDValue N0 = N->getOperand(0);
+    SDValue N1 = N->getOperand(1);
+    SDValue CMP0 = N0->getOperand(1);
+    SDValue CMP1 = N1->getOperand(1);
+    DebugLoc DL = N->getDebugLoc();
+
+    // The SETCCs should both refer to the same CMP.
+    if (CMP0.getOpcode() != X86ISD::CMP || CMP0 != CMP1)
+      return SDValue();
+
+    SDValue CMP00 = CMP0->getOperand(0);
+    SDValue CMP01 = CMP0->getOperand(1);
+    EVT     VT    = CMP00.getValueType();
+
+    if (VT == MVT::f32 || VT == MVT::f64) {
+      bool ExpectingFlags = false;
+      // Check for any users that want flags:
+      for (SDNode::use_iterator UI = N->use_begin(),
+             UE = N->use_end();
+           !ExpectingFlags && UI != UE; ++UI)
+        switch (UI->getOpcode()) {
+        default:
+        case ISD::BR_CC:
+        case ISD::BRCOND:
+        case ISD::SELECT:
+          ExpectingFlags = true;
+          break;
+        case ISD::CopyToReg:
+        case ISD::SIGN_EXTEND:
+        case ISD::ZERO_EXTEND:
+        case ISD::ANY_EXTEND:
+          break;
+        }
+
+      if (!ExpectingFlags) {
+        enum X86::CondCode cc0 = (enum X86::CondCode)N0.getConstantOperandVal(0);
+        enum X86::CondCode cc1 = (enum X86::CondCode)N1.getConstantOperandVal(0);
+
+        if (cc1 == X86::COND_E || cc1 == X86::COND_NE) {
+          X86::CondCode tmp = cc0;
+          cc0 = cc1;
+          cc1 = tmp;
+        }
+
+        if ((cc0 == X86::COND_E  && cc1 == X86::COND_NP) ||
+            (cc0 == X86::COND_NE && cc1 == X86::COND_P)) {
+          bool is64BitFP = (CMP00.getValueType() == MVT::f64);
+          X86ISD::NodeType NTOperator = is64BitFP ?
+            X86ISD::FSETCCsd : X86ISD::FSETCCss;
+          // FIXME: need symbolic constants for these magic numbers.
+          // See X86ATTInstPrinter.cpp:printSSECC().
+          unsigned x86cc = (cc0 == X86::COND_E) ? 0 : 4;
+          SDValue OnesOrZeroesF = DAG.getNode(NTOperator, DL, MVT::f32, CMP00, CMP01,
+                                              DAG.getConstant(x86cc, MVT::i8));
+          SDValue OnesOrZeroesI = DAG.getNode(ISD::BITCAST, DL, MVT::i32,
+                                              OnesOrZeroesF);
+          SDValue ANDed = DAG.getNode(ISD::AND, DL, MVT::i32, OnesOrZeroesI,
+                                      DAG.getConstant(1, MVT::i32));
+          SDValue OneBitOfTruth = DAG.getNode(ISD::TRUNCATE, DL, MVT::i8, ANDed);
+          return OneBitOfTruth;
+        }
+      }
+    }
+  }
+  return SDValue();
+}
+
 static SDValue PerformAndCombine(SDNode *N, SelectionDAG &DAG,
                                  TargetLowering::DAGCombinerInfo &DCI,
                                  const X86Subtarget *Subtarget) {
   if (DCI.isBeforeLegalizeOps())
     return SDValue();
 
+  SDValue R = CMPEQCombine(N, DAG, DCI, Subtarget);
+  if (R.getNode())
+    return R;
+
   // Want to form PANDN nodes, in the hopes of then easily combining them with
   // OR and AND nodes to form PBLEND/PSIGN.
   EVT VT = N->getValueType(0);
@@ -11714,6 +11798,10 @@ static SDValue PerformOrCombine(SDNode *N, SelectionDAG &DAG,
   if (DCI.isBeforeLegalizeOps())
     return SDValue();
 
+  SDValue R = CMPEQCombine(N, DAG, DCI, Subtarget);
+  if (R.getNode())
+    return R;
+
   EVT VT = N->getValueType(0);
   if (VT != MVT::i16 && VT != MVT::i32 && VT != MVT::i64 && VT != MVT::v2i64)
     return SDValue();