[PATCH] D91719: [RISCV] Add support for using -msave-restore with tailcalls

[Edward Jones via Phabricator via llvm-commits]

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This introduces the use of a new compiler runtime library function which behaves the same as __riscv_restore_N, however instead of returning to the callee these functions do a tailcall to the function whose pointer is stored in t1. This allows the -msave-restore optimization to be applied even in a tailcall context. The new runtime library functions are called __riscv_restore_tailcall_X where X is the number of callee-saved registers which will be restored.

Original patch by Simon Cook.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D91719

Files:
  llvm/lib/Target/RISCV/RISCVFrameLowering.cpp
  llvm/lib/Target/RISCV/RISCVMachineFunctionInfo.h
  llvm/test/CodeGen/RISCV/saverestore.ll

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