AMDGPU/GlobalISel: Add support for amdgpu_vs calling convention

Reviewers: arsenm

Reviewed By: arsenm

Subscribers: kzhuravl, wdng, nhaehnle, yaxunl, rovka, kristof.beyls, igorb, dstuttard, tpr, llvm-commits, t-tye

Differential Revision: https://reviews.llvm.org/D35916

llvm-svn: 309675

1 files changed, 24 insertions, 4 deletions

diff --git a/llvm/lib/Target/AMDGPU/AMDGPUCallLowering.cpp b/llvm/lib/Target/AMDGPU/AMDGPUCallLowering.cpp
index 515cc07dd44..31ae706d91d 100644
--- a/llvm/lib/Target/AMDGPU/AMDGPUCallLowering.cpp
+++ b/llvm/lib/Target/AMDGPU/AMDGPUCallLowering.cpp
@@ -144,18 +144,38 @@ bool AMDGPUCallLowering::lowerFormalArguments(MachineIRBuilder &MIRBuilder,
   Function::const_arg_iterator CurOrigArg = F.arg_begin();
   const AMDGPUTargetLowering &TLI = *getTLI<AMDGPUTargetLowering>();
   for (unsigned i = 0; i != NumArgs; ++i, ++CurOrigArg) {
-    MVT ValVT = TLI.getValueType(DL, CurOrigArg->getType()).getSimpleVT();
+    EVT ValEVT = TLI.getValueType(DL, CurOrigArg->getType());
+
+    // We can only hanlde simple value types at the moment.
+    if (!ValEVT.isSimple())
+      return false;
+    MVT ValVT = ValEVT.getSimpleVT();
     ISD::ArgFlagsTy Flags;
+    ArgInfo OrigArg{VRegs[i], CurOrigArg->getType()};
+    setArgFlags(OrigArg, i + 1, DL, F);
     Flags.setOrigAlign(DL.getABITypeAlignment(CurOrigArg->getType()));
     CCAssignFn *AssignFn = CCAssignFnForCall(F.getCallingConv(),
                                              /*IsVarArg=*/false);
     bool Res =
-        AssignFn(i, ValVT, ValVT, CCValAssign::Full, Flags, CCInfo);
-    assert(!Res && "Call operand has unhandled type");
-    (void)Res;
+        AssignFn(i, ValVT, ValVT, CCValAssign::Full, OrigArg.Flags, CCInfo);
+
+    // Fail if we don't know how to handle this type.
+    if (Res)
+      return false;
   }
 
   Function::const_arg_iterator Arg = F.arg_begin();
+
+  if (F.getCallingConv() == CallingConv::AMDGPU_VS) {
+    for (unsigned i = 0; i != NumArgs; ++i, ++Arg) {
+      CCValAssign &VA = ArgLocs[i];
+      MRI.addLiveIn(VA.getLocReg(), VRegs[i]);
+      MIRBuilder.getMBB().addLiveIn(VA.getLocReg());
+      MIRBuilder.buildCopy(VRegs[i], VA.getLocReg());
+    }
+    return true;
+  }
+
   for (unsigned i = 0; i != NumArgs; ++i, ++Arg) {
     // FIXME: We should be getting DebugInfo from the arguments some how.
     CCValAssign &VA = ArgLocs[i];