jrtc27 added inline comments.

================
Comment at: llvm/lib/Target/RISCV/RISCVFrameLowering.cpp:668
+        .setMIFlag(MachineInstr::FrameSetup);
+
+    // Add registers spilled in libcall as liveins.
----------------
lewis-revill wrote:
> shiva0217 wrote:
> > GCC will generate stack adjustment and GPR callee saved CFIs for the save 
> > libcalls. Should we do the same?
> I'm not familiar with the use of the CFI offset stuff, though just to be 
> sure, you're saying that in addition to the manually-added `.cfi_offset`s in 
> the libcalls themselves we would want to add them in our frame too?
Yes. The CFI use is completely ignorant of any control flow. It goes to the 
start of the function, and walks forward, executing every `.cfi_*` directive 
until reaching the current point in the code. Since the libcalls (and thus 
their CFI directives) are not inline in the function, they are completely 
invisible to the CFI machinery. Thus, their side-effects must be duplicated 
straight after the calls to them.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D62686/new/

https://reviews.llvm.org/D62686



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