Add XCore support for arbitrary-sized aggregate returns.

llvm-svn: 88802

3 files changed, 60 insertions, 0 deletions

diff --git a/llvm/lib/Target/XCore/XCoreISelLowering.cpp b/llvm/lib/Target/XCore/XCoreISelLowering.cpp
index 0e1e1efc613..16e68fe7b2d 100644
--- a/llvm/lib/Target/XCore/XCoreISelLowering.cpp
+++ b/llvm/lib/Target/XCore/XCoreISelLowering.cpp
@@ -918,6 +918,17 @@ XCoreTargetLowering::LowerCCCArguments(SDValue Chain,
 //               Return Value Calling Convention Implementation
 //===----------------------------------------------------------------------===//
 
+bool XCoreTargetLowering::
+CanLowerReturn(CallingConv::ID CallConv, bool isVarArg,
+               const SmallVectorImpl<EVT> &OutTys,
+               const SmallVectorImpl<ISD::ArgFlagsTy> &ArgsFlags,
+               SelectionDAG &DAG) {
+  SmallVector<CCValAssign, 16> RVLocs;
+  CCState CCInfo(CallConv, isVarArg, getTargetMachine(),
+                 RVLocs, *DAG.getContext());
+  return CCInfo.CheckReturn(OutTys, ArgsFlags, RetCC_XCore);
+}
+
 SDValue
 XCoreTargetLowering::LowerReturn(SDValue Chain,
                                  CallingConv::ID CallConv, bool isVarArg,
diff --git a/llvm/lib/Target/XCore/XCoreISelLowering.h b/llvm/lib/Target/XCore/XCoreISelLowering.h
index ef8555e3da1..10631afb020 100644
--- a/llvm/lib/Target/XCore/XCoreISelLowering.h
+++ b/llvm/lib/Target/XCore/XCoreISelLowering.h
@@ -159,6 +159,12 @@ namespace llvm {
                   CallingConv::ID CallConv, bool isVarArg,
                   const SmallVectorImpl<ISD::OutputArg> &Outs,
                   DebugLoc dl, SelectionDAG &DAG);
+
+    virtual bool
+      CanLowerReturn(CallingConv::ID CallConv, bool isVarArg,
+                     const SmallVectorImpl<EVT> &OutTys,
+                     const SmallVectorImpl<ISD::ArgFlagsTy> &ArgsFlags,
+                     SelectionDAG &DAG);
   };
 }
 
diff --git a/llvm/test/CodeGen/XCore/bigstructret.ll b/llvm/test/CodeGen/XCore/bigstructret.ll
new file mode 100644
index 00000000000..56af930cc40
--- /dev/null
+++ b/llvm/test/CodeGen/XCore/bigstructret.ll
@@ -0,0 +1,43 @@
+; RUN: llc < %s -march=xcore | FileCheck %s
+
+%0 = type { i32, i32, i32, i32 }
+%1 = type { i32, i32, i32, i32, i32 }
+
+; Structs of 4 words can be returned in registers
+define internal fastcc %0 @ReturnBigStruct() nounwind readnone {
+entry:
+  %0 = insertvalue %0 zeroinitializer, i32 12, 0
+  %1 = insertvalue %0 %0, i32 24, 1
+  %2 = insertvalue %0 %1, i32 48, 2
+  %3 = insertvalue %0 %2, i32 24601, 3
+  ret %0 %3
+}
+; CHECK: ReturnBigStruct:
+; CHECK: ldc r0, 12
+; CHECK: ldc r1, 24
+; CHECK: ldc r2, 48
+; CHECK: ldc r3, 24601
+; CHECK: retsp 0
+
+; Structs bigger than 4 words are returned via a hidden hidden sret-parameter
+define internal fastcc %1 @ReturnBigStruct2() nounwind readnone {
+entry:
+  %0 = insertvalue %1 zeroinitializer, i32 12, 0
+  %1 = insertvalue %1 %0, i32 24, 1
+  %2 = insertvalue %1 %1, i32 48, 2
+  %3 = insertvalue %1 %2, i32 24601, 3
+  %4 = insertvalue %1 %3, i32 4321, 4
+  ret %1 %4
+}
+; CHECK: ReturnBigStruct2:
+; CHECK: ldc r1, 4321
+; CHECK: stw r1, r0[4]
+; CHECK: ldc r1, 24601
+; CHECK: stw r1, r0[3]
+; CHECK: ldc r1, 48
+; CHECK: stw r1, r0[2]
+; CHECK: ldc r1, 24
+; CHECK: stw r1, r0[1]
+; CHECK: ldc r1, 12
+; CHECK: stw r1, r0[0]
+; CHECK: retsp 0