LegalizeDAG: Support promoting [US]DIV and [US]REM operations

Summary:
AMDGPU will need this one i16 is added as a legal type.  This is tested by:

test/CodeGen/AMDGPU/sdiv.ll
test/CodeGen/AMDGPU/sdivrem24.ll
test/CodeGen/AMDGPU/udiv.ll
test/CodeGen/AMDGPU/udivrem24.ll

Reviewers: bogner, efriedma

Subscribers: efriedma, wdng, llvm-commits

Differential Revision: https://reviews.llvm.org/D25699

llvm-svn: 285199

1 files changed, 18 insertions, 1 deletions

diff --git a/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
index c468a0fabc1..e48e6fa8aee 100644
--- a/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
@@ -4148,6 +4148,10 @@ void SelectionDAGLegalize::PromoteNode(SDNode *Node) {
     ReplacedNode(Node);
     break;
   }
+  case ISD::SDIV:
+  case ISD::SREM:
+  case ISD::UDIV:
+  case ISD::UREM:
   case ISD::AND:
   case ISD::OR:
   case ISD::XOR: {
@@ -4157,7 +4161,20 @@ void SelectionDAGLegalize::PromoteNode(SDNode *Node) {
       TruncOp = ISD::BITCAST;
     } else {
       assert(OVT.isInteger() && "Cannot promote logic operation");
-      ExtOp   = ISD::ANY_EXTEND;
+
+      switch (Node->getOpcode()) {
+      default:
+        ExtOp = ISD::ANY_EXTEND;
+        break;
+      case ISD::SDIV:
+      case ISD::SREM:
+        ExtOp = ISD::SIGN_EXTEND;
+        break;
+      case ISD::UDIV:
+      case ISD::UREM:
+        ExtOp = ISD::ZERO_EXTEND;
+        break;
+      }
       TruncOp = ISD::TRUNCATE;
     }
     // Promote each of the values to the new type.