[PATCH] D89237: [RISCV] Do not grow the stack a second time when we need to realign the stack

[Roger Ferrer Ibanez via Phabricator via llvm-commits]

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This is a first change needed to fix a crash in which the emergency spill splot ends being out of reach. This happens when we run the register scavenger after we have eliminated the frame indexes. The fix for the actual crash will come in a later change.

This change removes an extra stack size increase we do in `RISCVFrameLowering::determineFrameLayout`.

My understanding is that we don't have to change the size of the stack here as `PEI::calculateFrameObjectOffsets` is already doing this (see https://github.com/llvm/llvm-project/blob/539381da26096df54ccf862088c8242498a7dcae/llvm/lib/CodeGen/PrologEpilogInserter.cpp#L1085 ) with the right size accounting the extra alignment as kept in `MaxAlign` (see https://github.com/llvm/llvm-project/blob/539381da26096df54ccf862088c8242498a7dcae/llvm/lib/CodeGen/PrologEpilogInserter.cpp#L1079 ).


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D89237

Files:
  llvm/lib/Target/RISCV/RISCVFrameLowering.cpp
  llvm/test/CodeGen/RISCV/stack-realignment-with-variable-sized-objects.ll
  llvm/test/CodeGen/RISCV/stack-realignment.ll

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