[llvm-commits] [llvm] r57243 - in /llvm/trunk: lib/CodeGen/SelectionDAG/LegalizeDAG.cpp test/CodeGen/Alpha/add128.ll test/CodeGen/Alpha/sub128.ll

Andrew Lenharth alenhar2 at cs.uiuc.edu
Tue Oct 7 07:15:44 PDT 2008


Author: alenhar2
Date: Tue Oct  7 09:15:42 2008
New Revision: 57243

URL: http://llvm.org/viewvc/llvm-project?rev=57243&view=rev
Log:
Expand arith on machines without carry flags

Added:
    llvm/trunk/test/CodeGen/Alpha/sub128.ll
Modified:
    llvm/trunk/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
    llvm/trunk/test/CodeGen/Alpha/add128.ll

Modified: llvm/trunk/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp?rev=57243&r1=57242&r2=57243&view=diff

==============================================================================
--- llvm/trunk/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp (original)
+++ llvm/trunk/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp Tue Oct  7 09:15:42 2008
@@ -6431,7 +6431,6 @@
         break;
       }
     }
-    
     // Expand the subcomponents.
     SDValue LHSL, LHSH, RHSL, RHSH;
     ExpandOp(Node->getOperand(0), LHSL, LHSH);
@@ -6442,16 +6441,41 @@
     LoOps[1] = RHSL;
     HiOps[0] = LHSH;
     HiOps[1] = RHSH;
-    if (Node->getOpcode() == ISD::ADD) {
-      Lo = DAG.getNode(ISD::ADDC, VTList, LoOps, 2);
-      HiOps[2] = Lo.getValue(1);
-      Hi = DAG.getNode(ISD::ADDE, VTList, HiOps, 3);
+    if(TLI.isOperationLegal(ISD::ADDC, NVT)) {
+      if (Node->getOpcode() == ISD::ADD) {
+        Lo = DAG.getNode(ISD::ADDC, VTList, LoOps, 2);
+        HiOps[2] = Lo.getValue(1);
+        Hi = DAG.getNode(ISD::ADDE, VTList, HiOps, 3);
+      } else {
+        Lo = DAG.getNode(ISD::SUBC, VTList, LoOps, 2);
+        HiOps[2] = Lo.getValue(1);
+        Hi = DAG.getNode(ISD::SUBE, VTList, HiOps, 3);
+      }
+      break;
     } else {
-      Lo = DAG.getNode(ISD::SUBC, VTList, LoOps, 2);
-      HiOps[2] = Lo.getValue(1);
-      Hi = DAG.getNode(ISD::SUBE, VTList, HiOps, 3);
+      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 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 Carry2 = DAG.getNode(ISD::SELECT, NVT, Cmp2,
+                                    DAG.getConstant(1, NVT), 
+                                    Carry1);
+        Hi = DAG.getNode(ISD::ADD, NVT, Hi, Carry2);
+      } else {
+        Lo = DAG.getNode(ISD::SUB, VTList, LoOps, 2);
+        Hi = DAG.getNode(ISD::SUB, VTList, HiOps, 2);
+        SDValue Cmp = DAG.getSetCC(NVT, LoOps[0], LoOps[1], ISD::SETULT);
+        SDValue Borrow = DAG.getNode(ISD::SELECT, NVT, Cmp,
+                                     DAG.getConstant(1, NVT), 
+                                     DAG.getConstant(0, NVT));
+        Hi = DAG.getNode(ISD::SUB, NVT, Hi, Borrow);
+      }
+      break;
     }
-    break;
   }
     
   case ISD::ADDC:

Modified: llvm/trunk/test/CodeGen/Alpha/add128.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/Alpha/add128.ll?rev=57243&r1=57242&r2=57243&view=diff

==============================================================================
--- llvm/trunk/test/CodeGen/Alpha/add128.ll (original)
+++ llvm/trunk/test/CodeGen/Alpha/add128.ll Tue Oct  7 09:15:42 2008
@@ -1,7 +1,6 @@
 ;test for ADDC and ADDE expansion
 ;
 ; RUN: llvm-as < %s | llc -march=alpha
-; XFAIL: *
 
 define i128 @add128(i128 %x, i128 %y) {
 entry:

Added: llvm/trunk/test/CodeGen/Alpha/sub128.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/Alpha/sub128.ll?rev=57243&view=auto

==============================================================================
--- llvm/trunk/test/CodeGen/Alpha/sub128.ll (added)
+++ llvm/trunk/test/CodeGen/Alpha/sub128.ll Tue Oct  7 09:15:42 2008
@@ -0,0 +1,9 @@
+;test for SUBC and SUBE expansion
+;
+; RUN: llvm-as < %s | llc -march=alpha
+
+define i128 @sub128(i128 %x, i128 %y) {
+entry:
+	%tmp = sub i128 %y, %x
+	ret i128 %tmp
+}





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