MS ABI: Return sret parameters when using inalloca
Previously the X86 backend would look for the sret attribute and handle
this for us. inalloca takes that all away, so we have to do the return
ourselves now.
llvm-svn: 202097
diff --git a/clang/lib/CodeGen/CGCall.cpp b/clang/lib/CodeGen/CGCall.cpp
index a21e478..756b0b2 100644
--- a/clang/lib/CodeGen/CGCall.cpp
+++ b/clang/lib/CodeGen/CGCall.cpp
@@ -940,7 +940,15 @@
break;
case ABIArgInfo::InAlloca:
- resultType = llvm::Type::getVoidTy(getLLVMContext());
+ if (retAI.getInAllocaSRet()) {
+ // sret things on win32 aren't void, they return the sret pointer.
+ QualType ret = FI.getReturnType();
+ llvm::Type *ty = ConvertType(ret);
+ unsigned addressSpace = Context.getTargetAddressSpace(ret);
+ resultType = llvm::PointerType::get(ty, addressSpace);
+ } else {
+ resultType = llvm::Type::getVoidTy(getLLVMContext());
+ }
break;
case ABIArgInfo::Indirect: {
@@ -1779,7 +1787,17 @@
switch (RetAI.getKind()) {
case ABIArgInfo::InAlloca:
- // Do nothing; aggregrates get evaluated directly into the destination.
+ // Aggregrates get evaluated directly into the destination. Sometimes we
+ // need to return the sret value in a register, though.
+ assert(hasAggregateEvaluationKind(RetTy));
+ if (RetAI.getInAllocaSRet()) {
+ llvm::Function::arg_iterator EI = CurFn->arg_end();
+ --EI;
+ llvm::Value *ArgStruct = EI;
+ llvm::Value *SRet =
+ Builder.CreateStructGEP(ArgStruct, RetAI.getInAllocaFieldIndex());
+ RV = Builder.CreateLoad(SRet, "sret");
+ }
break;
case ABIArgInfo::Indirect: {