[llvm-commits] [llvm] r57247 - /llvm/trunk/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp

[Andrew Lenharth]

Author: alenhar2
Date: Tue Oct  7 12:03:15 2008
New Revision: 57247

URL: http://llvm.org/viewvc/llvm-project?rev=57247&view=rev
Log:
Use ADDC if it is valid at any smaller size.  fixes test/Codegen/Generic/i128-addsub.ll on x86

Modified:
    llvm/trunk/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp

Modified: llvm/trunk/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp?rev=57247&r1=57246&r2=57247&view=diff

==============================================================================
--- llvm/trunk/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp (original)
+++ llvm/trunk/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp Tue Oct  7 12:03:15 2008
@@ -6441,7 +6441,20 @@
     LoOps[1] = RHSL;
     HiOps[0] = LHSH;
     HiOps[1] = RHSH;
-    if(TLI.isOperationLegal(ISD::ADDC, NVT)) {
+    //cascaded check to see if any smaller size has a a carry flag.
+    unsigned OpV = Node->getOpcode() == ISD::ADD ? ISD::ADDC : ISD::SUBC;
+    bool hasCarry = false;
+    if (NVT == MVT::i64)
+      hasCarry |= TLI.isOperationLegal(OpV, MVT::i32)
+        | TLI.isOperationLegal(OpV, MVT::i16)
+        | TLI.isOperationLegal(OpV, MVT::i8);
+    if (NVT == MVT::i32)
+      hasCarry |= TLI.isOperationLegal(OpV, MVT::i16)
+        | TLI.isOperationLegal(OpV, MVT::i8);
+    if (NVT == MVT::i16)
+      hasCarry |= TLI.isOperationLegal(OpV, MVT::i8);
+      
+    if(hasCarry) {
       if (Node->getOpcode() == ISD::ADD) {
         Lo = DAG.getNode(ISD::ADDC, VTList, LoOps, 2);
         HiOps[2] = Lo.getValue(1);
@@ -6456,11 +6469,13 @@
       if (Node->getOpcode() == ISD::ADD) {
         Lo = DAG.getNode(ISD::ADD, VTList, LoOps, 2);
         Hi = DAG.getNode(ISD::ADD, VTList, HiOps, 2);
-        SDValue Cmp1 = DAG.getSetCC(NVT, Lo, LoOps[0], ISD::SETULT);
+        SDValue Cmp1 = DAG.getSetCC(TLI.getSetCCResultType(Lo),
+                                    Lo, LoOps[0], ISD::SETULT);
         SDValue Carry1 = DAG.getNode(ISD::SELECT, NVT, Cmp1,
                                      DAG.getConstant(1, NVT), 
                                      DAG.getConstant(0, NVT));
-        SDValue Cmp2 = DAG.getSetCC(NVT, Lo, LoOps[1], ISD::SETULT);
+        SDValue Cmp2 = DAG.getSetCC(TLI.getSetCCResultType(Lo),
+                                    Lo, LoOps[1], ISD::SETULT);
         SDValue Carry2 = DAG.getNode(ISD::SELECT, NVT, Cmp2,
                                     DAG.getConstant(1, NVT), 
                                     Carry1);