AMDGPU: Fix handling of alignment padding in DAG argument lowering

This was completely broken if there was ever a struct argument, as
this information is thrown away during the argument analysis.

The offsets as passed in to LowerFormalArguments are not useful,
as they partially depend on the legalized result register type,
and they don't consider the alignment in the first place.

Ignore the Ins array, and instead figure out from the raw IR type
what we need to do. This seems to fix the padding computation
if the DAG lowering is forced (and stops breaking arguments
following padded arguments if the arguments were only partially
lowered in the IR)

llvm-svn: 337021

1 files changed, 4 insertions, 17 deletions

diff --git a/llvm/lib/Target/AMDGPU/R600ISelLowering.cpp b/llvm/lib/Target/AMDGPU/R600ISelLowering.cpp
index 4110e6a28d6..113d6249fa6 100644
--- a/llvm/lib/Target/AMDGPU/R600ISelLowering.cpp
+++ b/llvm/lib/Target/AMDGPU/R600ISelLowering.cpp
@@ -50,18 +50,6 @@
 
 using namespace llvm;
 
-static bool allocateKernArg(unsigned ValNo, MVT ValVT, MVT LocVT,
-                            CCValAssign::LocInfo LocInfo,
-                            ISD::ArgFlagsTy ArgFlags, CCState &State) {
-  MachineFunction &MF = State.getMachineFunction();
-  AMDGPUMachineFunction *MFI = MF.getInfo<AMDGPUMachineFunction>();
-
-  uint64_t Offset = MFI->allocateKernArg(LocVT.getStoreSize(),
-                                         ArgFlags.getOrigAlign());
-  State.addLoc(CCValAssign::getCustomMem(ValNo, ValVT, Offset, LocVT, LocInfo));
-  return true;
-}
-
 #include "R600GenCallingConv.inc"
 
 R600TargetLowering::R600TargetLowering(const TargetMachine &TM,
@@ -234,7 +222,7 @@ R600TargetLowering::R600TargetLowering(const TargetMachine &TM,
     setOperationAction(ISD::FMA, MVT::f32, Expand);
     setOperationAction(ISD::FMA, MVT::f64, Expand);
   }
- 
+
   // FIXME: This was moved from AMDGPUTargetLowering, I'm not sure if we
   // need it for R600.
   if (!Subtarget->hasFP32Denormals())
@@ -1583,7 +1571,7 @@ CCAssignFn *R600TargetLowering::CCAssignFnForCall(CallingConv::ID CC,
   case CallingConv::C:
   case CallingConv::Fast:
   case CallingConv::Cold:
-    return CC_R600_Kernel;
+    llvm_unreachable("kernels should not be handled here");
   case CallingConv::AMDGPU_VS:
   case CallingConv::AMDGPU_GS:
   case CallingConv::AMDGPU_PS:
@@ -1658,13 +1646,12 @@ SDValue R600TargetLowering::LowerFormalArguments(
 
     unsigned ValBase = ArgLocs[In.getOrigArgIndex()].getLocMemOffset();
     unsigned PartOffset = VA.getLocMemOffset();
-    unsigned Offset = Subtarget->getExplicitKernelArgOffset(MF.getFunction()) +
-                      VA.getLocMemOffset();
 
     MachinePointerInfo PtrInfo(UndefValue::get(PtrTy), PartOffset - ValBase);
     SDValue Arg = DAG.getLoad(
         ISD::UNINDEXED, Ext, VT, DL, Chain,
-        DAG.getConstant(Offset, DL, MVT::i32), DAG.getUNDEF(MVT::i32), PtrInfo,
+        DAG.getConstant(PartOffset, DL, MVT::i32), DAG.getUNDEF(MVT::i32),
+        PtrInfo,
         MemVT, /* Alignment = */ 4, MachineMemOperand::MONonTemporal |
                                         MachineMemOperand::MODereferenceable |
                                         MachineMemOperand::MOInvariant);