- Add target lowering hooks that specify which setcc conditions are illegal,
i.e. conditions that cannot be checked with a single instruction. For example,
SETONE and SETUEQ on x86.
- Teach legalizer to implement *illegal* setcc as a and / or of a number of
legal setcc nodes. For now, only implement FP conditions. e.g. SETONE is
implemented as SETO & SETNE, SETUEQ is SETUO | SETEQ.
- Move x86 target over.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@57542 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp b/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
index 9fa0628..ec4cd87 100644
--- a/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
@@ -193,6 +193,11 @@
                                     SmallPtrSet<SDNode*, 32> &NodesLeadingTo);
 
   void LegalizeSetCCOperands(SDValue &LHS, SDValue &RHS, SDValue &CC);
+  void LegalizeSetCCCondCode(MVT VT, SDValue &LHS, SDValue &RHS, SDValue &CC);
+  void LegalizeSetCC(MVT VT, SDValue &LHS, SDValue &RHS, SDValue &CC) {
+    LegalizeSetCCOperands(LHS, RHS, CC);
+    LegalizeSetCCCondCode(VT, LHS, RHS, CC);
+  }
     
   SDValue ExpandLibCall(RTLIB::Libcall LC, SDNode *Node, bool isSigned,
                           SDValue &Hi);
@@ -1886,10 +1891,10 @@
     Tmp3 = Node->getOperand(3);              // RHS
     Tmp4 = Node->getOperand(1);              // CC
 
-    LegalizeSetCCOperands(Tmp2, Tmp3, Tmp4);
+    LegalizeSetCC(Node->getValueType(0), Tmp2, Tmp3, Tmp4);
     LastCALLSEQ_END = DAG.getEntryNode();
 
-    // If we didn't get both a LHS and RHS back from LegalizeSetCCOperands,
+    // If we didn't get both a LHS and RHS back from LegalizeSetCC,
     // the LHS is a legal SETCC itself.  In this case, we need to compare
     // the result against zero to select between true and false values.
     if (Tmp3.getNode() == 0) {
@@ -2772,9 +2777,9 @@
     Tmp4 = LegalizeOp(Node->getOperand(3));   // False
     SDValue CC = Node->getOperand(4);
     
-    LegalizeSetCCOperands(Tmp1, Tmp2, CC);
+    LegalizeSetCC(Node->getValueType(0), Tmp1, Tmp2, CC);
     
-    // If we didn't get both a LHS and RHS back from LegalizeSetCCOperands,
+    // If we didn't get both a LHS and RHS back from LegalizeSetCC,
     // the LHS is a legal SETCC itself.  In this case, we need to compare
     // the result against zero to select between true and false values.
     if (Tmp2.getNode() == 0) {
@@ -2798,7 +2803,7 @@
     Tmp1 = Node->getOperand(0);
     Tmp2 = Node->getOperand(1);
     Tmp3 = Node->getOperand(2);
-    LegalizeSetCCOperands(Tmp1, Tmp2, Tmp3);
+    LegalizeSetCC(Node->getValueType(0), Tmp1, Tmp2, Tmp3);
     
     // If we had to Expand the SetCC operands into a SELECT node, then it may 
     // not always be possible to return a true LHS & RHS.  In this case, just 
@@ -4877,6 +4882,50 @@
   RHS = Tmp2;
 }
 
+/// LegalizeSetCCCondCode - Legalize a SETCC with given LHS and RHS and
+/// condition code CC on the current target. This routine assumes LHS and rHS
+/// have already been legalized by LegalizeSetCCOperands. It expands SETCC with
+/// illegal condition code into AND / OR of multiple SETCC values.
+void SelectionDAGLegalize::LegalizeSetCCCondCode(MVT VT,
+                                                 SDValue &LHS, SDValue &RHS,
+                                                 SDValue &CC) {
+  MVT OpVT = LHS.getValueType();
+  ISD::CondCode CCCode = cast<CondCodeSDNode>(CC)->get();
+  switch (TLI.getCondCodeAction(CCCode, OpVT)) {
+  default: assert(0 && "Unknown condition code action!");
+  case TargetLowering::Legal:
+    // Nothing to do.
+    break;
+  case TargetLowering::Expand: {
+    ISD::CondCode CC1 = ISD::SETCC_INVALID, CC2 = ISD::SETCC_INVALID;
+    unsigned Opc = 0;
+    switch (CCCode) {
+    default: assert(0 && "Don't know how to expand this condition!"); abort();
+    case ISD::SETOEQ: CC1 = ISD::SETO;  CC2 = ISD::SETEQ; Opc = ISD::AND; break;
+    case ISD::SETOGT: CC1 = ISD::SETO;  CC2 = ISD::SETGT; Opc = ISD::AND; break;
+    case ISD::SETOGE: CC1 = ISD::SETO;  CC2 = ISD::SETGE; Opc = ISD::AND; break;
+    case ISD::SETOLT: CC1 = ISD::SETO;  CC2 = ISD::SETLT; Opc = ISD::AND; break;
+    case ISD::SETOLE: CC1 = ISD::SETO;  CC2 = ISD::SETLE; Opc = ISD::AND; break;
+    case ISD::SETONE: CC1 = ISD::SETO;  CC2 = ISD::SETNE; Opc = ISD::AND; break;
+    case ISD::SETUEQ: CC1 = ISD::SETUO; CC2 = ISD::SETEQ; Opc = ISD::OR;  break;
+    case ISD::SETUGT: CC1 = ISD::SETUO; CC2 = ISD::SETGT; Opc = ISD::OR;  break;
+    case ISD::SETUGE: CC1 = ISD::SETUO; CC2 = ISD::SETGE; Opc = ISD::OR;  break;
+    case ISD::SETULT: CC1 = ISD::SETUO; CC2 = ISD::SETLT; Opc = ISD::OR;  break;
+    case ISD::SETULE: CC1 = ISD::SETUO; CC2 = ISD::SETLE; Opc = ISD::OR;  break;
+    case ISD::SETUNE: CC1 = ISD::SETUO; CC2 = ISD::SETNE; Opc = ISD::OR;  break;
+    // FIXME: Implement more expansions.
+    }
+
+    SDValue SetCC1 = DAG.getSetCC(VT, LHS, RHS, CC1);
+    SDValue SetCC2 = DAG.getSetCC(VT, LHS, RHS, CC2);
+    LHS = DAG.getNode(Opc, VT, SetCC1, SetCC2);
+    RHS = SDValue();
+    CC  = SDValue();
+    break;
+  }
+  }
+}
+
 /// EmitStackConvert - Emit a store/load combination to the stack.  This stores
 /// SrcOp to a stack slot of type SlotVT, truncating it if needed.  It then does
 /// a load from the stack slot to DestVT, extending it if needed.