[llvm] [RISCV] Allow spilling to unused Zcmp Stack (PR #125959)

[Craig Topper via llvm-commits]

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@@ -1847,11 +1847,16 @@ bool RISCVFrameLowering::assignCalleeSavedSpillSlots(
       MFI.setStackID(FrameIdx, TargetStackID::ScalableVector);
   }
 
-  // Allocate a fixed object that covers the full push or libcall size.
   if (RVFI->isPushable(MF)) {
-    if (int64_t PushSize = RVFI->getRVPushStackSize())
-      MFI.CreateFixedSpillStackObject(PushSize, -PushSize);
+    // Allocate a fixed object that covers all the registers that are pushed.
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topperc wrote:

I'm a bit curious if this object is needed at all.

https://github.com/llvm/llvm-project/pull/125959