Fix a tblgen problem handling variable_ops in tblgen instruction

definitions. This adds a new construct, "discard", for indicating
that a named node in the input matching pattern is to be discarded,
instead of corresponding to a node in the output pattern. This
allows tblgen to know where the arguments for the varaible_ops are
supposed to begin.

This fixes "rdar://5791600", whatever that is ;-).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51699 91177308-0d34-0410-b5e6-96231b3b80d8

4 files changed, 10 insertions, 32 deletions

diff --git a/lib/Target/Target.td b/lib/Target/Target.td
index a268e16..92c4057 100644
--- a/lib/Target/Target.td
+++ b/lib/Target/Target.td
@@ -259,6 +259,12 @@ def ins;
 /// of operands.
 def variable_ops;
 
+/// discard definition - Mark this operand as being matched in the input
+/// but omitted from the output. This is necessary in some situations
+/// involving variable_ops to help the pattern matcher determine which
+/// input nodes to forward on to the variable_ops portion of the output.
+def discard;
+
 /// ptr_rc definition - Mark this operand as being a pointer value whose
 /// register class is resolved dynamically via a callback to TargetInstrInfo.
 /// FIXME: We should probably change this to a class which contain a list of
diff --git a/lib/Target/TargetSelectionDAG.td b/lib/Target/TargetSelectionDAG.td
index f194443..9def220 100644
--- a/lib/Target/TargetSelectionDAG.td
+++ b/lib/Target/TargetSelectionDAG.td
@@ -470,6 +470,7 @@ class PatLeaf<dag frag, code pred = [{}], SDNodeXForm xform = NOOP_SDNodeXForm>
 def vtInt      : PatLeaf<(vt),  [{ return MVT::isInteger(N->getVT()); }]>;
 def vtFP       : PatLeaf<(vt),  [{ return MVT::isFloatingPoint(N->getVT()); }]>;
 
+def immAllZeros : PatLeaf<(imm), [{ return N->isNullValue(); }]>;
 def immAllOnes : PatLeaf<(imm), [{ return N->isAllOnesValue(); }]>;
 def immAllOnesV: PatLeaf<(build_vector), [{
   return ISD::isBuildVectorAllOnes(N);
diff --git a/lib/Target/X86/X86ISelDAGToDAG.cpp b/lib/Target/X86/X86ISelDAGToDAG.cpp
index 576661d..bb8c58a 100644
--- a/lib/Target/X86/X86ISelDAGToDAG.cpp
+++ b/lib/Target/X86/X86ISelDAGToDAG.cpp
@@ -1175,35 +1175,6 @@ SDNode *X86DAGToDAGISel::Select(SDOperand N) {
     case X86ISD::GlobalBaseReg: 
       return getGlobalBaseReg();
 
-    // FIXME: This is a workaround for a tblgen problem: rdar://5791600
-    case X86ISD::RET_FLAG:
-      if (ConstantSDNode *Amt = dyn_cast<ConstantSDNode>(N.getOperand(1))) {
-        if (Amt->getSignExtended() != 0) break;
-        
-        // Match (X86retflag 0).
-        SDOperand Chain = N.getOperand(0);
-        bool HasInFlag = N.getOperand(N.getNumOperands()-1).getValueType()
-                          == MVT::Flag;
-        SmallVector<SDOperand, 8> Ops0;
-        AddToISelQueue(Chain);
-        SDOperand InFlag(0, 0);
-        if (HasInFlag) {
-          InFlag = N.getOperand(N.getNumOperands()-1);
-          AddToISelQueue(InFlag);
-        }
-        for (unsigned i = 2, e = N.getNumOperands()-(HasInFlag?1:0); i != e;
-             ++i) {
-          AddToISelQueue(N.getOperand(i));
-          Ops0.push_back(N.getOperand(i));
-        }
-        Ops0.push_back(Chain);
-        if (HasInFlag)
-          Ops0.push_back(InFlag);
-        return CurDAG->getTargetNode(X86::RET, MVT::Other,
-                                     &Ops0[0], Ops0.size());
-      }
-      break;
-      
     case ISD::ADD: {
       // Turn ADD X, c to MOV32ri X+c. This cannot be done with tblgen'd
       // code and is matched first so to prevent it from being turned into
diff --git a/lib/Target/X86/X86InstrInfo.td b/lib/Target/X86/X86InstrInfo.td
index 843fbd0..d0bd955 100644
--- a/lib/Target/X86/X86InstrInfo.td
+++ b/lib/Target/X86/X86InstrInfo.td
@@ -45,7 +45,7 @@ def SDT_X86CallSeqStart : SDCallSeqStart<[ SDTCisVT<0, i32> ]>;
 def SDT_X86CallSeqEnd   : SDCallSeqEnd<[ SDTCisVT<0, i32>,
                                          SDTCisVT<1, i32> ]>;
 
-def SDT_X86Call   : SDTypeProfile<0, 1, [SDTCisVT<0, iPTR>]>;
+def SDT_X86Call   : SDTypeProfile<0, -1, [SDTCisVT<0, iPTR>]>;
 
 def SDTX86RepStr  : SDTypeProfile<0, 1, [SDTCisVT<0, OtherVT>]>;
 
@@ -322,9 +322,9 @@ let neverHasSideEffects = 1, isNotDuplicable = 1 in
 // Return instructions.
 let isTerminator = 1, isReturn = 1, isBarrier = 1,
     hasCtrlDep = 1, FPForm = SpecialFP, FPFormBits = SpecialFP.Value in {
-  def RET    : I   <0xC3, RawFrm, (outs), (ins variable_ops),
+  def RET    : I   <0xC3, RawFrm, (outs), (ins discard:$amt, variable_ops),
                     "ret",
-                    [/*(X86retflag 0)*/ /*FIXME: Disabled: rdar://5791600*/]>;
+                    [(X86retflag immAllZeros:$amt)]>;
   def RETI   : Ii16<0xC2, RawFrm, (outs), (ins i16imm:$amt, variable_ops),
                     "ret\t$amt",
                     [(X86retflag imm:$amt)]>;