1 files changed, 55 insertions, 17 deletions

diff --git a/mlir/lib/Target/LLVMIR/ModuleImport.cpp b/mlir/lib/Target/LLVMIR/ModuleImport.cpp
index 6f56a17..77094d4 100644
--- a/mlir/lib/Target/LLVMIR/ModuleImport.cpp
+++ b/mlir/lib/Target/LLVMIR/ModuleImport.cpp
@@ -1993,8 +1993,8 @@ ModuleImport::convertCallOperands(llvm::CallBase *callInst,
 /// Checks if `callType` and `calleeType` are compatible and can be represented
 /// in MLIR.
 static LogicalResult
-verifyFunctionTypeCompatibility(LLVMFunctionType callType,
-                                LLVMFunctionType calleeType) {
+checkFunctionTypeCompatibility(LLVMFunctionType callType,
+                               LLVMFunctionType calleeType) {
   if (callType.getReturnType() != calleeType.getReturnType())
     return failure();
 
@@ -2020,7 +2020,9 @@ verifyFunctionTypeCompatibility(LLVMFunctionType callType,
 }
 
 FailureOr<LLVMFunctionType>
-ModuleImport::convertFunctionType(llvm::CallBase *callInst) {
+ModuleImport::convertFunctionType(llvm::CallBase *callInst,
+                                  bool &isIncompatibleCall) {
+  isIncompatibleCall = false;
   auto castOrFailure = [](Type convertedType) -> FailureOr<LLVMFunctionType> {
     auto funcTy = dyn_cast_or_null<LLVMFunctionType>(convertedType);
     if (!funcTy)
@@ -2043,11 +2045,14 @@ ModuleImport::convertFunctionType(llvm::CallBase *callInst) {
   if (failed(calleeType))
     return failure();
 
-  // Compare the types to avoid constructing illegal call/invoke operations.
-  if (failed(verifyFunctionTypeCompatibility(*callType, *calleeType))) {
+  // Compare the types and notify users via `isIncompatibleCall` if they are not
+  // compatible.
+  if (failed(checkFunctionTypeCompatibility(*callType, *calleeType))) {
+    isIncompatibleCall = true;
     Location loc = translateLoc(callInst->getDebugLoc());
-    return emitError(loc) << "incompatible call and callee types: " << *callType
-                          << " and " << *calleeType;
+    emitWarning(loc) << "incompatible call and callee types: " << *callType
+                     << " and " << *calleeType;
+    return callType;
   }
 
   return calleeType;
@@ -2164,16 +2169,34 @@ LogicalResult ModuleImport::convertInstruction(llvm::Instruction *inst) {
                 /*operand_attrs=*/nullptr)
             .getOperation();
       }
-      FailureOr<LLVMFunctionType> funcTy = convertFunctionType(callInst);
+      bool isIncompatibleCall;
+      FailureOr<LLVMFunctionType> funcTy =
+          convertFunctionType(callInst, isIncompatibleCall);
       if (failed(funcTy))
         return failure();
 
-      FlatSymbolRefAttr callee = convertCalleeName(callInst);
-      auto callOp = builder.create<CallOp>(loc, *funcTy, callee, *operands);
+      FlatSymbolRefAttr callee = nullptr;
+      if (isIncompatibleCall) {
+        // Use an indirect call (in order to represent valid and verifiable LLVM
+        // IR). Build the indirect call by passing an empty `callee` operand and
+        // insert into `operands` to include the indirect call target.
+        FlatSymbolRefAttr calleeSym = convertCalleeName(callInst);
+        Value indirectCallVal = builder.create<LLVM::AddressOfOp>(
+            loc, LLVM::LLVMPointerType::get(context), calleeSym);
+        operands->insert(operands->begin(), indirectCallVal);
+      } else {
+        // Regular direct call using callee name.
+        callee = convertCalleeName(callInst);
+      }
+      CallOp callOp = builder.create<CallOp>(loc, *funcTy, callee, *operands);
+
       if (failed(convertCallAttributes(callInst, callOp)))
         return failure();
-      // Handle parameter and result attributes.
-      convertParameterAttributes(callInst, callOp, builder);
+
+      // Handle parameter and result attributes unless it's an incompatible
+      // call.
+      if (!isIncompatibleCall)
+        convertParameterAttributes(callInst, callOp, builder);
       return callOp.getOperation();
     }();
 
@@ -2238,12 +2261,25 @@ LogicalResult ModuleImport::convertInstruction(llvm::Instruction *inst) {
                                  unwindArgs)))
       return failure();
 
-    FailureOr<LLVMFunctionType> funcTy = convertFunctionType(invokeInst);
+    bool isIncompatibleInvoke;
+    FailureOr<LLVMFunctionType> funcTy =
+        convertFunctionType(invokeInst, isIncompatibleInvoke);
     if (failed(funcTy))
       return failure();
 
-    FlatSymbolRefAttr calleeName = convertCalleeName(invokeInst);
-
+    FlatSymbolRefAttr calleeName = nullptr;
+    if (isIncompatibleInvoke) {
+      // Use an indirect invoke (in order to represent valid and verifiable LLVM
+      // IR). Build the indirect invoke by passing an empty `callee` operand and
+      // insert into `operands` to include the indirect invoke target.
+      FlatSymbolRefAttr calleeSym = convertCalleeName(invokeInst);
+      Value indirectInvokeVal = builder.create<LLVM::AddressOfOp>(
+          loc, LLVM::LLVMPointerType::get(context), calleeSym);
+      operands->insert(operands->begin(), indirectInvokeVal);
+    } else {
+      // Regular direct invoke using callee name.
+      calleeName = convertCalleeName(invokeInst);
+    }
     // Create the invoke operation. Normal destination block arguments will be
     // added later on to handle the case in which the operation result is
     // included in this list.
@@ -2254,8 +2290,10 @@ LogicalResult ModuleImport::convertInstruction(llvm::Instruction *inst) {
     if (failed(convertInvokeAttributes(invokeInst, invokeOp)))
       return failure();
 
-    // Handle parameter and result attributes.
-    convertParameterAttributes(invokeInst, invokeOp, builder);
+    // Handle parameter and result attributes unless it's an incompatible
+    // invoke.
+    if (!isIncompatibleInvoke)
+      convertParameterAttributes(invokeInst, invokeOp, builder);
 
     if (!invokeInst->getType()->isVoidTy())
       mapValue(inst, invokeOp.getResults().front());