[PATCH] D94949: [AArch64][RegAllocFast] Add findSpillBefore to TargetRegisterInfo

Wed Jan 27 00:30:01 PST 2021

tmatheson marked an inline comment as done.
tmatheson added inline comments.

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Comment at: llvm/lib/Target/ARM/ARMRegisterInfo.cpp:22-23
+/// instruction right after the current one, but in the case of ldrex/strex
+/// pairs we need to avoid introducing stores between the exclusive
+/// instructions, otherwise we will invalidate them.
+MachineBasicBlock::iterator
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arsenm wrote:
> Could you use a bundle for this?
Potentially, can you elaborate on what you mean exactly? One approach could be to create a bundle in `AtomicExpand::insertRMWLLSCLoop` to bundle the results of `emitLoadLinked` and `emitStoreConditional`. However, this would also need some sort of hook from AtomicExpandPass to use in order to do this in a target dependent way.

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https://reviews.llvm.org/D94949