[WebAssembly] Implement prolog/epilog insertion and FrameIndex elimination

[oota-llvm.git] / lib / Target / WebAssembly / WebAssemblyISelLowering.cpp

diff --git a/lib/Target/WebAssembly/WebAssemblyISelLowering.cpp b/lib/Target/WebAssembly/WebAssemblyISelLowering.cpp
index 76df63b54074bce38f86734ebaf2e1ca12c3f08d..a5ca08f12bdbaa9999e022e79d95865f730999e6 100644 (file)
--- a/lib/Target/WebAssembly/WebAssemblyISelLowering.cpp
+++ b/lib/Target/WebAssembly/WebAssemblyISelLowering.cpp
@@ -167,6 +167,8 @@ WebAssemblyTargetLowering::WebAssemblyTargetLowering(
   setOperationAction(ISD::STACKRESTORE, MVT::Other, Expand);
   setOperationAction(ISD::DYNAMIC_STACKALLOC, MVTPtr, Expand);
 
+  setOperationAction(ISD::FrameIndex, MVT::i32, Custom);
+
   // Expand these forms; we pattern-match the forms that we can handle in isel.
   for (auto T : {MVT::i32, MVT::i64, MVT::f32, MVT::f64})
     for (auto Op : {ISD::BR_CC, ISD::SELECT_CC})
@@ -520,6 +522,8 @@ SDValue WebAssemblyTargetLowering::LowerOperation(SDValue Op,
   default:
     llvm_unreachable("unimplemented operation lowering");
     return SDValue();
+  case ISD::FrameIndex:
+    return LowerFrameIndex(Op, DAG);
   case ISD::GlobalAddress:
     return LowerGlobalAddress(Op, DAG);
   case ISD::ExternalSymbol:
@@ -533,6 +537,12 @@ SDValue WebAssemblyTargetLowering::LowerOperation(SDValue Op,
   }
 }
 
+SDValue WebAssemblyTargetLowering::LowerFrameIndex(SDValue Op,
+                                                   SelectionDAG &DAG) const {
+  int FI = cast<FrameIndexSDNode>(Op)->getIndex();
+  return DAG.getTargetFrameIndex(FI, Op.getValueType());
+}
+
 SDValue WebAssemblyTargetLowering::LowerGlobalAddress(SDValue Op,
                                                       SelectionDAG &DAG) const {
   SDLoc DL(Op);