[llvm-branch-commits] [llvm] [AArch64][SME] Support split ZPR and PPR area allocation (PR #142392)

[Sander de Smalen via llvm-branch-commits]

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@@ -1251,9 +1260,17 @@ AArch64FrameLowering::getFrameIndexReferenceFromSP(const MachineFunction &MF,
       isTargetWindows(MF) && AFI->getSVECalleeSavedStackSize();
   if (MFI.isScalableStackID(FI)) {
     if (FPAfterSVECalleeSaves &&
-        -ObjectOffset <= (int64_t)AFI->getSVECalleeSavedStackSize())
+        -ObjectOffset <= (int64_t)AFI->getSVECalleeSavedStackSize()) {
+      assert(!AFI->hasSplitSVEObjects() &&
+             "split-sve-objects not supported with FPAfterSVECalleeSaves");
       return StackOffset::getScalable(ObjectOffset);
-    return StackOffset::get(-((int64_t)AFI->getCalleeSavedStackSize()),
+    }
+    StackOffset AccessOffset{};
+    if (AFI->hasSplitSVEObjects() &&
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sdesmalen-arm wrote:

Can you add a comment explaining here why the PPR stack size must be subtracted?

https://github.com/llvm/llvm-project/pull/142392