Teach the SelectionDAG ISel how to turn ConstantPacked values into

constant nodes with vector types.  Also teach the asm printer how to print
ConstantPacked constant pool entries.  This allows us to generate altivec
code such as the following, which adds a vector constantto a packed float.

LCPI1_0:  <4 x float> < float 0.0e+0, float 0.0e+0, float 0.0e+0, float 1.0e+0 >
        .space  4
        .space  4
        .space  4
        .long   1065353216      ; float 1
        .text
        .align  4
        .globl  _foo
_foo:
        lis r2, ha16(LCPI1_0)
        la r2, lo16(LCPI1_0)(r2)
        li r4, 0
        lvx v0, r4, r2
        lvx v1, r4, r3
        vaddfp v0, v1, v0
        stvx v0, r4, r3
        blr

For the llvm code:

void %foo(<4 x float> * %a) {
entry:
  %tmp1 = load <4 x float> * %a;
  %tmp2 = add <4 x float> %tmp1, < float 0.0, float 0.0, float 0.0, float 1.0 >
  store <4 x float> %tmp2, <4 x float> *%a
  ret void
}


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@24616 91177308-0d34-0410-b5e6-96231b3b80d8

4 files changed, 62 insertions, 5 deletions

diff --git a/lib/CodeGen/AsmPrinter.cpp b/lib/CodeGen/AsmPrinter.cpp
index 0e9802d5c1..a9bd4ebd11 100644
--- a/lib/CodeGen/AsmPrinter.cpp
+++ b/lib/CodeGen/AsmPrinter.cpp
@@ -11,6 +11,7 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "llvm/DerivedTypes.h"
 #include "llvm/CodeGen/AsmPrinter.h"
 #include "llvm/Constants.h"
 #include "llvm/Module.h"
@@ -326,6 +327,13 @@ void AsmPrinter::EmitGlobalConstant(const Constant *CV) {
       }
       return;
     }
+  } else if (const ConstantPacked *CP = dyn_cast<ConstantPacked>(CV)) {
+    const PackedType *PTy = CP->getType();
+    
+    for (unsigned I = 0, E = PTy->getNumElements(); I < E; ++I)
+      EmitGlobalConstant(CP->getOperand(I));
+    
+    return;
   }
 
   const Type *type = CV->getType();
diff --git a/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp b/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
index c02fc9ac69..18da8168a9 100644
--- a/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
@@ -690,6 +690,32 @@ SDOperand SelectionDAGLegalize::LegalizeOp(SDOperand Op) {
     }
     break;
   }
+  case ISD::ConstantVec: {
+    // We assume that vector constants are not legal, and will be immediately
+    // spilled to the constant pool.
+    //
+    // FIXME: revisit this when we have some kind of mechanism by which targets
+    // can decided legality of vector constants, of which there may be very
+    // many.
+    //
+    // Create a ConstantPacked, and put it in the constant pool.
+    std::vector<Constant*> CV;
+    MVT::ValueType VT = Node->getValueType(0);
+    for (unsigned I = 0, E = Node->getNumOperands(); I < E; ++I) {
+      SDOperand OpN = Node->getOperand(I);
+      const Type* OpNTy = MVT::getTypeForValueType(OpN.getValueType());
+      if (MVT::isFloatingPoint(VT))
+        CV.push_back(ConstantFP::get(OpNTy, 
+                                     cast<ConstantFPSDNode>(OpN)->getValue()));
+      else
+        CV.push_back(ConstantUInt::get(OpNTy,
+                                       cast<ConstantSDNode>(OpN)->getValue()));
+    }
+    Constant *CP = ConstantPacked::get(CV);
+    SDOperand CPIdx = DAG.getConstantPool(CP, Node->getValueType(0));
+    Result = DAG.getLoad(VT, DAG.getEntryNode(), CPIdx, DAG.getSrcValue(NULL));
+    break;
+  }
   case ISD::TokenFactor:
     if (Node->getNumOperands() == 2) {
       bool Changed = false;
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index 0605352f9f..f9ea84f301 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -501,8 +501,6 @@ SDOperand SelectionDAG::getConstantFP(double Val, MVT::ValueType VT) {
   return SDOperand(N, 0);
 }
 
-
-
 SDOperand SelectionDAG::getGlobalAddress(const GlobalValue *GV,
                                          MVT::ValueType VT, int offset) {
   SDNode *&N = GlobalValues[std::make_pair(GV, offset)];
@@ -1837,6 +1835,7 @@ const char *SDNode::getOperationName(const SelectionDAG *G) const {
   case ISD::Constant:      return "Constant";
   case ISD::TargetConstant: return "TargetConstant";
   case ISD::ConstantFP:    return "ConstantFP";
+  case ISD::ConstantVec:   return "ConstantVec";
   case ISD::GlobalAddress: return "GlobalAddress";
   case ISD::TargetGlobalAddress: return "TargetGlobalAddress";
   case ISD::FrameIndex:    return "FrameIndex";
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
index 0f5743860d..97597e053f 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
@@ -282,7 +282,8 @@ public:
     SDOperand &N = NodeMap[V];
     if (N.Val) return N;
 
-    MVT::ValueType VT = TLI.getValueType(V->getType());
+    const Type *VTy = V->getType();
+    MVT::ValueType VT = TLI.getValueType(VTy);
     if (Constant *C = const_cast<Constant*>(dyn_cast<Constant>(V)))
       if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
         visit(CE->getOpcode(), *CE);
@@ -296,6 +297,30 @@ public:
         return N = DAG.getNode(ISD::UNDEF, VT);
       } else if (ConstantFP *CFP = dyn_cast<ConstantFP>(C)) {
         return N = DAG.getConstantFP(CFP->getValue(), VT);
+      } else if (const PackedType *PTy = dyn_cast<PackedType>(VTy)) {
+        unsigned NumElements = PTy->getNumElements();
+        MVT::ValueType PVT = TLI.getValueType(PTy->getElementType());
+        MVT::ValueType TVT = MVT::getVectorType(PVT, NumElements);
+        
+        // Now that we know the number and type of the elements, push a
+        // Constant or ConstantFP node onto the ops list for each element of
+        // the packed constant.
+        std::vector<SDOperand> Ops;
+        for (unsigned i = 0; i < NumElements; ++i) {
+          const Constant *CEl = C->getOperand(i);
+          if (MVT::isFloatingPoint(PVT))
+            Ops.push_back(DAG.getConstantFP(cast<ConstantFP>(CEl)->getValue(), 
+                          PVT));
+          else
+            Ops.push_back(
+                    DAG.getConstant(cast<ConstantIntegral>(CEl)->getRawValue(),
+                          PVT));
+        }
+        // Handle the case where we have a 1-element vector, in which
+        // case we want to immediately turn it into a scalar constant.
+        if (Ops.size() == 1)
+          return N = Ops[0];
+        return N = DAG.getNode(ISD::ConstantVec, TVT, Ops);
       } else {
         // Canonicalize all constant ints to be unsigned.
         return N = DAG.getConstant(cast<ConstantIntegral>(C)->getRawValue(),VT);
@@ -784,8 +809,7 @@ void SelectionDAGLowering::visitLoad(LoadInst &I) {
   const Type *Ty = I.getType();
   SDOperand L;
   
-  if (Type::PackedTyID == Ty->getTypeID()) {
-    const PackedType *PTy = cast<PackedType>(Ty);
+  if (const PackedType *PTy = dyn_cast<PackedType>(Ty)) {
     unsigned NumElements = PTy->getNumElements();
     MVT::ValueType PVT = TLI.getValueType(PTy->getElementType());
     MVT::ValueType TVT = MVT::getVectorType(PVT, NumElements);