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

[Chris Lattner]

Changes in directory llvm/lib/CodeGen/SelectionDAG:

LegalizeDAG.cpp updated: 1.392 -> 1.393
---
Log message:

Compile X << 1 (where X is a long-long) to:

        addl %ecx, %ecx
        adcl %eax, %eax

instead of:

        movl %ecx, %edx
        addl %edx, %edx
        shrl $31, %ecx
        addl %eax, %eax
        orl %ecx, %eax

and to:

        addc r5, r5, r5
        adde r4, r4, r4

instead of:

        slwi r2,r9,1
        srwi r0,r11,31
        slwi r3,r11,1
        or r2,r0,r2

on PPC.



---
Diffs of the changes:  (+24 -7)

 LegalizeDAG.cpp |   31 ++++++++++++++++++++++++-------
 1 files changed, 24 insertions(+), 7 deletions(-)


Index: llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
diff -u llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp:1.392 llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp:1.393
--- llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp:1.392	Sat Sep  9 01:03:30 2006
+++ llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp	Tue Sep 12 22:50:39 2006
@@ -4559,6 +4559,24 @@
       }
     }
     
+    // If ADDC/ADDE are supported and if the shift amount is a constant 1, emit 
+    // this X << 1 as X+X.
+    if (ConstantSDNode *ShAmt = dyn_cast<ConstantSDNode>(ShiftAmt)) {
+      if (ShAmt->getValue() == 1 && TLI.isOperationLegal(ISD::ADDC, NVT) && 
+          TLI.isOperationLegal(ISD::ADDE, NVT)) {
+        SDOperand LoOps[2], HiOps[3];
+        ExpandOp(Node->getOperand(0), LoOps[0], HiOps[0]);
+        SDVTList VTList = DAG.getVTList(LoOps[0].getValueType(), MVT::Flag);
+        LoOps[1] = LoOps[0];
+        Lo = DAG.getNode(ISD::ADDC, VTList, LoOps, 2);
+
+        HiOps[1] = HiOps[0];
+        HiOps[2] = Lo.getValue(1);
+        Hi = DAG.getNode(ISD::ADDE, VTList, HiOps, 3);
+        break;
+      }
+    }
+    
     // If we can emit an efficient shift operation, do so now.
     if (ExpandShift(ISD::SHL, Node->getOperand(0), ShiftAmt, Lo, Hi))
       break;
@@ -4657,21 +4675,20 @@
     SDOperand LHSL, LHSH, RHSL, RHSH;
     ExpandOp(Node->getOperand(0), LHSL, LHSH);
     ExpandOp(Node->getOperand(1), RHSL, RHSH);
-    const MVT::ValueType *VTs =
-      DAG.getNodeValueTypes(LHSL.getValueType(),MVT::Flag);
-    SDOperand LoOps[2], HiOps[2];
+    SDVTList VTList = DAG.getVTList(LHSL.getValueType(), MVT::Flag);
+    SDOperand LoOps[2], HiOps[3];
     LoOps[0] = LHSL;
     LoOps[1] = RHSL;
     HiOps[0] = LHSH;
     HiOps[1] = RHSH;
     if (Node->getOpcode() == ISD::ADD) {
-      Lo = DAG.getNode(ISD::ADDC, VTs, 2, LoOps, 2);
+      Lo = DAG.getNode(ISD::ADDC, VTList, LoOps, 2);
       HiOps[2] = Lo.getValue(1);
-      Hi = DAG.getNode(ISD::ADDE, VTs, 2, HiOps, 3);
+      Hi = DAG.getNode(ISD::ADDE, VTList, HiOps, 3);
     } else {
-      Lo = DAG.getNode(ISD::SUBC, VTs, 2, LoOps, 2);
+      Lo = DAG.getNode(ISD::SUBC, VTList, LoOps, 2);
       HiOps[2] = Lo.getValue(1);
-      Hi = DAG.getNode(ISD::SUBE, VTs, 2, HiOps, 3);
+      Hi = DAG.getNode(ISD::SUBE, VTList, HiOps, 3);
     }
     break;
   }