[clang] [llvm] [RISCV] RISCV vector calling convention (1/2) (PR #77560)

[Craig Topper via cfe-commits]

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@@ -1006,15 +1077,24 @@ RISCVFrameLowering::assignRVVStackObjectOffsets(MachineFunction &MF) const {
   MachineFrameInfo &MFI = MF.getFrameInfo();
   // Create a buffer of RVV objects to allocate.
   SmallVector<int, 8> ObjectsToAllocate;
-  for (int I = 0, E = MFI.getObjectIndexEnd(); I != E; ++I) {
-    unsigned StackID = MFI.getStackID(I);
-    if (StackID != TargetStackID::ScalableVector)
-      continue;
-    if (MFI.isDeadObjectIndex(I))
-      continue;
+  auto pushRVVObjects = [&](int FIBegin, int FIEnd) {
+    for (int I = FIBegin, E = FIEnd; I != E; ++I) {
+      unsigned StackID = MFI.getStackID(I);
+      if (StackID != TargetStackID::ScalableVector)
+        continue;
+      if (MFI.isDeadObjectIndex(I))
+        continue;
 
-    ObjectsToAllocate.push_back(I);
-  }
+      ObjectsToAllocate.push_back(I);
+    }
+  };
+  // First push RVV Callee Saved object, then push RVV stack object
+  std::vector<CalleeSavedInfo> &CSI = MF.getFrameInfo().getCalleeSavedInfo();
+  const auto &RVVCSI = getRVVCalleeSavedInfo(MF, CSI);
+  if (RVVCSI.size())
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topperc wrote:

`!RVVCSI.empty()`?

https://github.com/llvm/llvm-project/pull/77560