[PATCH 0/5] riscv: optimize string functions and add kunit tests

[Feng Jiang]

This series introduces optimized assembly implementations for several 
string functions on the RISC-V architecture (strnlen, strchr, and strrchr). 
To ensure correctness and prevent regressions, it also extends the 
string_kunit test suite with new cases.

The patchset is organized as follows:
- Patches 1-2: Enhance lib/string_kunit.c with new test cases for 
  strlen and strnlen to establish a baseline for verification.
- Patches 3-5: Provide the RISC-V specific optimized implementations 
  for strnlen, strchr, and strrchr.

Testing:
All patches have been verified using the KUnit framework on QEMU 
virt machine (riscv64). All string-related tests passed.

Changes:
- v1: Initial submission.

---

Feng Jiang (5):
  lib/string_kunit: add test case for strlen
  lib/string_kunit: add test case for strnlen
  riscv: lib: add strnlen implementation
  riscv: lib: add strchr implementation
  riscv: lib: add strrchr implementation

 arch/riscv/include/asm/string.h |   9 ++
 arch/riscv/lib/Makefile         |   3 +
 arch/riscv/lib/strchr.S         |  35 +++++++
 arch/riscv/lib/strnlen.S        | 164 ++++++++++++++++++++++++++++++++
 arch/riscv/lib/strrchr.S        |  37 +++++++
 arch/riscv/purgatory/Makefile   |  11 ++-
 lib/tests/string_kunit.c        |  53 +++++++++++
 7 files changed, 311 insertions(+), 1 deletion(-)
 create mode 100644 arch/riscv/lib/strchr.S
 create mode 100644 arch/riscv/lib/strnlen.S
 create mode 100644 arch/riscv/lib/strrchr.S

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2.25.1