[llvm] r176105 - R600/SI: Add promotion of e32 to e64 in operand folding

[Christian Konig]

Author: ckoenig
Date: Tue Feb 26 11:52:47 2013
New Revision: 176105

URL: http://llvm.org/viewvc/llvm-project?rev=176105&view=rev
Log:
R600/SI: Add promotion of e32 to e64 in operand folding

Signed-off-by: Christian König <christian.koenig at amd.com>
Reviewed-by: Tom Stellard <thomas.stellard at amd.com>

Modified:
    llvm/trunk/lib/Target/R600/SIISelLowering.cpp

Modified: llvm/trunk/lib/Target/R600/SIISelLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/R600/SIISelLowering.cpp?rev=176105&r1=176104&r2=176105&view=diff
==============================================================================
--- llvm/trunk/lib/Target/R600/SIISelLowering.cpp (original)
+++ llvm/trunk/lib/Target/R600/SIISelLowering.cpp Tue Feb 26 11:52:47 2013
@@ -501,6 +501,13 @@ SDNode *SITargetLowering::PostISelFoldin
   unsigned NumDefs = Desc->getNumDefs();
   unsigned NumOps = Desc->getNumOperands();
 
+  // e64 version if available, -1 otherwise
+  int OpcodeE64 = AMDGPU::getVOPe64(Opcode);
+  const MCInstrDesc *DescE64 = OpcodeE64 == -1 ? 0 : &TII->get(OpcodeE64);
+
+  assert(!DescE64 || DescE64->getNumDefs() == NumDefs);
+  assert(!DescE64 || DescE64->getNumOperands() == (NumOps + 4));
+
   int32_t Immediate = Desc->getSize() == 4 ? 0 : -1;
   bool HaveVSrc = false, HaveSSrc = false;
 
@@ -532,6 +539,7 @@ SDNode *SITargetLowering::PostISelFoldin
 
   // Second go over the operands and try to fold them
   std::vector<SDValue> Ops;
+  bool Promote2e64 = false;
   for (unsigned i = 0, e = Node->getNumOperands(), Op = NumDefs;
        i != e && Op < NumOps; ++i, ++Op) {
 
@@ -558,6 +566,20 @@ SDNode *SITargetLowering::PostISelFoldin
         SDValue Tmp = Ops[1];
         Ops[1] = Ops[0];
         Ops[0] = Tmp;
+
+      } else if (DescE64 && !Immediate) {
+        // Test if it makes sense to switch to e64 encoding
+
+        RegClass = DescE64->OpInfo[Op].RegClass;
+        int32_t TmpImm = -1;
+        if ((isVSrc(RegClass) || isSSrc(RegClass)) &&
+            foldImm(Ops[i], TmpImm, ScalarSlotUsed)) {
+
+          Immediate = -1;
+          Promote2e64 = true;
+          Desc = DescE64;
+          DescE64 = 0;
+        }
       }
       continue;
     }
@@ -569,10 +591,20 @@ SDNode *SITargetLowering::PostISelFoldin
     }
   }
 
+  if (Promote2e64) {
+    // Add the modifier flags while promoting
+    for (unsigned i = 0; i < 4; ++i)
+      Ops.push_back(DAG.getTargetConstant(0, MVT::i32));
+  }
+
   // Add optional chain and glue
   for (unsigned i = NumOps - NumDefs, e = Node->getNumOperands(); i < e; ++i)
     Ops.push_back(Node->getOperand(i));
 
-  // Update the instruction parameters
-  return DAG.UpdateNodeOperands(Node, Ops.data(), Ops.size());
+  // Either create a complete new or update the current instruction
+  if (Promote2e64)
+    return DAG.getMachineNode(OpcodeE64, Node->getDebugLoc(),
+                              Node->getVTList(), Ops.data(), Ops.size());
+  else
+    return DAG.UpdateNodeOperands(Node, Ops.data(), Ops.size());
 }