[llvm-commits] CVS: llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp SelectionDAG.cpp

[Chris Lattner]

Changes in directory llvm/lib/CodeGen/SelectionDAG:

LegalizeDAG.cpp updated: 1.290 -> 1.291
SelectionDAG.cpp updated: 1.248 -> 1.249
---
Log message:

Legalize ConstantFP into TargetConstantFP when the target allows.  Implement
custom expansion of ConstantFP nodes.


---
Diffs of the changes:  (+39 -2)

 LegalizeDAG.cpp  |   19 ++++++++++++++++++-
 SelectionDAG.cpp |   22 +++++++++++++++++++++-
 2 files changed, 39 insertions(+), 2 deletions(-)


Index: llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
diff -u llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp:1.290 llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp:1.291
--- llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp:1.290	Sun Jan 29 00:00:45 2006
+++ llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp	Sun Jan 29 00:26:56 2006
@@ -272,6 +272,8 @@
   case ISD::BasicBlock:
   case ISD::TargetFrameIndex:
   case ISD::TargetConstant:
+  case ISD::TargetConstantFP:
+  case ISD::TargetConstantVec:
   case ISD::TargetConstantPool:
   case ISD::TargetGlobalAddress:
   case ISD::TargetExternalSymbol:
@@ -481,7 +483,22 @@
         break;
       }
 
-    if (!isLegal) {
+    // If this is a legal constant, turn it into a TargetConstantFP node.
+    if (isLegal) {
+      Result = DAG.getTargetConstantFP(CFP->getValue(), CFP->getValueType(0));
+      break;
+    }
+
+    switch (TLI.getOperationAction(ISD::ConstantFP, CFP->getValueType(0))) {
+    default: assert(0 && "This action is not supported yet!");
+    case TargetLowering::Custom:
+      Tmp3 = TLI.LowerOperation(Result, DAG);
+      if (Tmp3.Val) {
+        Result = Tmp3;
+        break;
+      }
+      // FALLTHROUGH
+    case TargetLowering::Expand:
       // Otherwise we need to spill the constant to memory.
       bool Extend = false;
 


Index: llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
diff -u llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp:1.248 llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp:1.249
--- llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp:1.248	Sat Jan 28 04:09:25 2006
+++ llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp	Sun Jan 29 00:26:56 2006
@@ -277,6 +277,11 @@
     Erased = ConstantFPs.erase(std::make_pair(V, N->getValueType(0)));
     break;
   }
+  case ISD::TargetConstantFP: {
+    uint64_t V = DoubleToBits(cast<ConstantFPSDNode>(N)->getValue());
+    Erased = TargetConstantFPs.erase(std::make_pair(V, N->getValueType(0)));
+    break;
+  }
   case ISD::STRING:
     Erased = StringNodes.erase(cast<StringSDNode>(N)->getValue());
     break;
@@ -606,7 +611,22 @@
   // we don't have issues with SNANs.
   SDNode *&N = ConstantFPs[std::make_pair(DoubleToBits(Val), VT)];
   if (N) return SDOperand(N, 0);
-  N = new ConstantFPSDNode(Val, VT);
+  N = new ConstantFPSDNode(false, Val, VT);
+  AllNodes.push_back(N);
+  return SDOperand(N, 0);
+}
+
+SDOperand SelectionDAG::getTargetConstantFP(double Val, MVT::ValueType VT) {
+  assert(MVT::isFloatingPoint(VT) && "Cannot create integer FP constant!");
+  if (VT == MVT::f32)
+    Val = (float)Val;  // Mask out extra precision.
+  
+  // Do the map lookup using the actual bit pattern for the floating point
+  // value, so that we don't have problems with 0.0 comparing equal to -0.0, and
+  // we don't have issues with SNANs.
+  SDNode *&N = TargetConstantFPs[std::make_pair(DoubleToBits(Val), VT)];
+  if (N) return SDOperand(N, 0);
+  N = new ConstantFPSDNode(true, Val, VT);
   AllNodes.push_back(N);
   return SDOperand(N, 0);
 }