Revert 239644.

[oota-llvm.git] / lib / Target / R600 / AMDGPUFrameLowering.cpp

diff --git a/lib/Target/R600/AMDGPUFrameLowering.cpp b/lib/Target/R600/AMDGPUFrameLowering.cpp
index 40f14d2f67c51626e29872ea711a1b4b0de9cfa7..8175786fb9b13b10b2119a3722f69e88d0aa038b 100644 (file)
--- a/lib/Target/R600/AMDGPUFrameLowering.cpp
+++ b/lib/Target/R600/AMDGPUFrameLowering.cpp
@@ -74,24 +74,33 @@ unsigned AMDGPUFrameLowering::getStackWidth(const MachineFunction &MF) const {
 int AMDGPUFrameLowering::getFrameIndexOffset(const MachineFunction &MF,
                                          int FI) const {
   const MachineFrameInfo *MFI = MF.getFrameInfo();
-  unsigned Offset = 0;
+  // Start the offset at 2 so we don't overwrite work group information.
+  // XXX: We should only do this when the shader actually uses this
+  // information.
+  unsigned OffsetBytes = 2 * (getStackWidth(MF) * 4);
   int UpperBound = FI == -1 ? MFI->getNumObjects() : FI;
 
   for (int i = MFI->getObjectIndexBegin(); i < UpperBound; ++i) {
-    unsigned Size = MFI->getObjectSize(i);
-    Offset += (Size / (getStackWidth(MF) * 4));
+    OffsetBytes = RoundUpToAlignment(OffsetBytes, MFI->getObjectAlignment(i));
+    OffsetBytes += MFI->getObjectSize(i);
+    // Each register holds 4 bytes, so we must always align the offset to at
+    // least 4 bytes, so that 2 frame objects won't share the same register.
+    OffsetBytes = RoundUpToAlignment(OffsetBytes, 4);
   }
-  return Offset;
+
+  if (FI != -1)
+    OffsetBytes = RoundUpToAlignment(OffsetBytes, MFI->getObjectAlignment(FI));
+
+  return OffsetBytes / (getStackWidth(MF) * 4);
 }
 
 const TargetFrameLowering::SpillSlot *
 AMDGPUFrameLowering::getCalleeSavedSpillSlots(unsigned &NumEntries) const {
   NumEntries = 0;
-  return 0;
-}
-void
-AMDGPUFrameLowering::emitPrologue(MachineFunction &MF) const {
+  return nullptr;
 }
+void AMDGPUFrameLowering::emitPrologue(MachineFunction &MF,
+                                       MachineBasicBlock &MBB) const {}
 void
 AMDGPUFrameLowering::emitEpilogue(MachineFunction &MF,
                                   MachineBasicBlock &MBB) const {