[RFC PATCH V3 08/43] rv64ilp32_abi: riscv: bitops: Adapt ctzw & clzw of zbb extension
From: guoren@kernel.org
Date: 2025-03-25 12:18:43
Also in:
bpf, kvm, kvm-riscv, linux-arch, linux-btrfs, linux-crypto, linux-fsdevel, linux-input, linux-media, linux-mm, linux-nfs, linux-perf-users, linux-riscv, linux-sctp, linux-serial, linux-usb, lkml, netdev, netfilter-devel
Subsystem:
bitops api, risc-v architecture, the rest · Maintainers:
Yury Norov, Paul Walmsley, Palmer Dabbelt, Albert Ou, Linus Torvalds
From: "Guo Ren (Alibaba DAMO Academy)" <guoren@kernel.org> The RV64ILP32 ABI is based on 64-bit ISA, but BITS_PER_LONG is 32. Use ctzw and clzw for int and long types instead of ctz and clz. Signed-off-by: Guo Ren (Alibaba DAMO Academy) <guoren@kernel.org> --- arch/riscv/include/asm/bitops.h | 21 +++++++++++++++++---- 1 file changed, 17 insertions(+), 4 deletions(-)
diff --git a/arch/riscv/include/asm/bitops.h b/arch/riscv/include/asm/bitops.h
index c6bd3d8354a9..d041b9e3ba84 100644
--- a/arch/riscv/include/asm/bitops.h
+++ b/arch/riscv/include/asm/bitops.h@@ -35,14 +35,27 @@ #include <asm/alternative-macros.h> #include <asm/hwcap.h> -#if (BITS_PER_LONG == 64) +#if (__riscv_xlen == 64) #define CTZW "ctzw " #define CLZW "clzw " + +#if (BITS_PER_LONG == 64) +#define CTZ "ctz " +#define CLZ "clz " #elif (BITS_PER_LONG == 32) +#define CTZ "ctzw " +#define CLZ "clzw " +#else +#error "Unexpected BITS_PER_LONG" +#endif + +#elif (__riscv_xlen == 32) #define CTZW "ctz " #define CLZW "clz " +#define CTZ "ctz " +#define CLZ "clz " #else -#error "Unexpected BITS_PER_LONG" +#error "Unexpected __riscv_xlen" #endif static __always_inline unsigned long variable__ffs(unsigned long word)
@@ -53,7 +66,7 @@ static __always_inline unsigned long variable__ffs(unsigned long word) asm volatile (".option push\n" ".option arch,+zbb\n" - "ctz %0, %1\n" + CTZ "%0, %1\n" ".option pop\n" : "=r" (word) : "r" (word) :);
@@ -82,7 +95,7 @@ static __always_inline unsigned long variable__fls(unsigned long word) asm volatile (".option push\n" ".option arch,+zbb\n" - "clz %0, %1\n" + CLZ "%0, %1\n" ".option pop\n" : "=r" (word) : "r" (word) :);
--
2.40.1