Zbb string optimizations and call support in alternatives
From: Heiko Stuebner <heiko.stuebner@...> Date: Mon, 9 Jan 2023 18:03:43 +0100
This series still tries to allow optimized string functions for specific extensions. The last approach of using an inline base function to hold the alternative calls did cause some issues in a number of places So instead of that we're now just using an alternative j at the beginning of the generic function to jump to a separate place inside the function itself. This of course needs a fixup for "j" instructions in alternative blocks, so that is provided here as well. Technically patch4 got a review from Andrew, but that was still with the inline approach, so I didn't bring it over to v4. changes since v3: - rebase on top of 6.2-rc1 + the applied alternative-call series - add alternative fixup for jal instructions - drop the inline functions and instead just jump changes since v2: - add patch fixing the c.jalr funct4 value - reword some commit messages - fix position of auipc addition patch (earlier) - fix compile errors from patch-reordering gone wrong (worked at the end of v2, but compiling individual patches caused issues) - patches are now tested individually - limit Zbb variants for GNU as for now (LLVM support for .option arch is still under review) - prevent str-functions from getting optimized to builtin-variants changes since v1: - a number of generalizations/cleanups for instruction parsing - use accessor function to access instructions (Emil) - actually patch the correct location when having more than one instruction in an alternative block - string function cleanups (comments etc) (Conor) - move zbb extension above s* extensions in cpu.c lists changes since rfc: - make Zbb code actually work - drop some unneeded patches - a lot of cleanups Heiko Stuebner (5): RISC-V: move some stray __RISCV_INSN_FUNCS definitions from kprobes RISC-V: add helpers for J-type immediate handling RISC-V: fix jal addresses in patched alternatives RISC-V: add infrastructure to allow different str* implementations RISC-V: add zbb support to string functions arch/riscv/Kconfig | 24 ++++ arch/riscv/include/asm/errata_list.h | 3 +- arch/riscv/include/asm/hwcap.h | 1 + arch/riscv/include/asm/insn.h | 36 ++++++ arch/riscv/include/asm/string.h | 12 ++ arch/riscv/kernel/alternative.c | 27 ++++ arch/riscv/kernel/cpu.c | 1 + arch/riscv/kernel/cpufeature.c | 18 +++ arch/riscv/kernel/probes/simulate-insn.h | 3 - arch/riscv/kernel/riscv_ksyms.c | 3 + arch/riscv/lib/Makefile | 3 + arch/riscv/lib/strcmp.S | 131 ++++++++++++++++++++ arch/riscv/lib/strlen.S | 142 +++++++++++++++++++++ arch/riscv/lib/strncmp.S | 151 +++++++++++++++++++++++ arch/riscv/purgatory/Makefile | 13 ++ 15 files changed, 564 insertions(+), 4 deletions(-) create mode 100644 arch/riscv/lib/strcmp.S create mode 100644 arch/riscv/lib/strlen.S create mode 100644 arch/riscv/lib/strncmp.S -- 2.35.1
Patches in this set
- [0001] RISC-V: move some stray __RISCV_INSN_FUNCS definitions (raw)
- [0002] RISC-V: add helpers for J-type immediate handling (raw)
- [0003] RISC-V: fix jal addresses in patched alternatives (raw)
- [0004] RISC-V: add infrastructure to allow different str* (raw)
- [0005] RISC-V: add zbb support to string functions (raw)
Statistics
- 5 individual patches
- 564 lines added
- 4 lines removed