[PATCH v5 12/18] riscv: Add RVV strcpy for multiarch and non-multiarch
Yao Zihong
zihong.plct@isrc.iscas.ac.cn
Tue Feb 3 15:05:36 GMT 2026
Co-authored-by: Hau Hsu <hau.hsu@sifive.com>
Co-authored-by: Jerry Shih <jerry.shih@sifive.com>
Signed-off-by: Yao Zihong <zihong.plct@isrc.iscas.ac.cn>
---
sysdeps/riscv/multiarch/strcpy-generic.c | 26 ++++++++
sysdeps/riscv/multiarch/strcpy-vector.S | 24 ++++++++
sysdeps/riscv/rvv/strcpy.S | 59 +++++++++++++++++++
.../unix/sysv/linux/riscv/multiarch/Makefile | 3 +
.../linux/riscv/multiarch/ifunc-impl-list.c | 5 ++
.../unix/sysv/linux/riscv/multiarch/strcpy.c | 56 ++++++++++++++++++
6 files changed, 173 insertions(+)
create mode 100644 sysdeps/riscv/multiarch/strcpy-generic.c
create mode 100644 sysdeps/riscv/multiarch/strcpy-vector.S
create mode 100644 sysdeps/riscv/rvv/strcpy.S
create mode 100644 sysdeps/unix/sysv/linux/riscv/multiarch/strcpy.c
diff --git a/sysdeps/riscv/multiarch/strcpy-generic.c b/sysdeps/riscv/multiarch/strcpy-generic.c
new file mode 100644
index 0000000000..8a29992570
--- /dev/null
+++ b/sysdeps/riscv/multiarch/strcpy-generic.c
@@ -0,0 +1,26 @@
+/* Re-include the default strcpy implementation.
+ Copyright (C) 2026 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+#include <string.h>
+
+#if IS_IN(libc)
+# define STRCPY __strcpy_generic
+# undef libc_hidden_builtin_def
+# define libc_hidden_builtin_def(x)
+# include <string/strcpy.c>
+#endif
diff --git a/sysdeps/riscv/multiarch/strcpy-vector.S b/sysdeps/riscv/multiarch/strcpy-vector.S
new file mode 100644
index 0000000000..f5381a98ce
--- /dev/null
+++ b/sysdeps/riscv/multiarch/strcpy-vector.S
@@ -0,0 +1,24 @@
+/* Re-include the RISC-V RVV based strcpy implementation.
+ Copyright (C) 2026 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+#if IS_IN(libc)
+# define STRCPY __strcpy_vector
+# undef libc_hidden_builtin_def
+# define libc_hidden_builtin_def(name)
+# include <sysdeps/riscv/rvv/strcpy.S>
+#endif
diff --git a/sysdeps/riscv/rvv/strcpy.S b/sysdeps/riscv/rvv/strcpy.S
new file mode 100644
index 0000000000..e73558d812
--- /dev/null
+++ b/sysdeps/riscv/rvv/strcpy.S
@@ -0,0 +1,59 @@
+/* RISC-V RVV based strcpy.
+ Copyright (C) 2026 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+#include <sysdep.h>
+#include <sys/asm.h>
+
+#ifndef STRCPY
+# define STRCPY strcpy
+#endif
+
+#define dst a0
+#define src a1
+#define dst_ptr a2
+
+#define ivl a3
+#define cur_vl a4
+#define active_elem_pos a5
+
+#define ELEM_LMUL_SETTING m1
+#define vmask1 v0
+#define vmask2 v1
+#define vstr1 v8
+#define vstr2 v16
+
+ENTRY (STRCPY)
+.option push
+.option arch, +v
+ mv dst_ptr, dst
+L(strcpy_loop):
+ vsetvli ivl, zero, e8, ELEM_LMUL_SETTING, ta, ma
+ vle8ff.v vstr1, (src)
+ vmseq.vx vmask2, vstr1, zero
+ csrr cur_vl, vl
+ vfirst.m active_elem_pos, vmask2
+ vmsif.m vmask1, vmask2
+ add src, src, cur_vl
+ vse8.v vstr1, (dst_ptr), vmask1.t
+ add dst_ptr, dst_ptr, cur_vl
+ bltz active_elem_pos, L(strcpy_loop)
+
+ ret
+.option pop
+END (STRCPY)
+libc_hidden_builtin_def (strcpy)
diff --git a/sysdeps/unix/sysv/linux/riscv/multiarch/Makefile b/sysdeps/unix/sysv/linux/riscv/multiarch/Makefile
index 3dfee5799c..5bbd789d46 100644
--- a/sysdeps/unix/sysv/linux/riscv/multiarch/Makefile
+++ b/sysdeps/unix/sysv/linux/riscv/multiarch/Makefile
@@ -37,6 +37,9 @@ sysdep_routines += \
strcmp \
strcmp-generic \
strcmp-vector \
+ strcpy \
+ strcpy-generic \
+ strcpy-vector \
# sysdep_routines
CFLAGS-memcpy_noalignment.c += -mno-strict-align
diff --git a/sysdeps/unix/sysv/linux/riscv/multiarch/ifunc-impl-list.c b/sysdeps/unix/sysv/linux/riscv/multiarch/ifunc-impl-list.c
index 872e8d12a7..3f00942167 100644
--- a/sysdeps/unix/sysv/linux/riscv/multiarch/ifunc-impl-list.c
+++ b/sysdeps/unix/sysv/linux/riscv/multiarch/ifunc-impl-list.c
@@ -105,5 +105,10 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
__strcmp_vector)
IFUNC_IMPL_ADD (array, i, strcmp, 1, __strcmp_generic))
+ IFUNC_IMPL (i, name, strcpy,
+ IFUNC_IMPL_ADD (array, i, strcpy, rvv_enabled,
+ __strcpy_vector)
+ IFUNC_IMPL_ADD (array, i, strcpy, 1, __strcpy_generic))
+
return 0;
}
diff --git a/sysdeps/unix/sysv/linux/riscv/multiarch/strcpy.c b/sysdeps/unix/sysv/linux/riscv/multiarch/strcpy.c
new file mode 100644
index 0000000000..ba47e8f89c
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/riscv/multiarch/strcpy.c
@@ -0,0 +1,56 @@
+/* Multiple versions of strcpy.
+ All versions must be listed in ifunc-impl-list.c.
+ Copyright (C) 2026 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+#if IS_IN (libc)
+/* Redefine strcpy so that the compiler won't complain about the type
+ mismatch with the IFUNC selector in strong_alias, below. */
+# undef strcpy
+# define strcpy __redirect_strcpy
+# include <stdint.h>
+# include <string.h>
+# include <ifunc-init.h>
+# include <riscv-ifunc.h>
+# include <sys/hwprobe.h>
+
+extern __typeof (__redirect_strcpy) __libc_strcpy;
+
+extern __typeof (__redirect_strcpy) __strcpy_generic attribute_hidden;
+extern __typeof (__redirect_strcpy) __strcpy_vector attribute_hidden;
+
+static inline __typeof (__redirect_strcpy) *
+select_strcpy_ifunc (uint64_t dl_hwcap, __riscv_hwprobe_t hwprobe_func)
+{
+ unsigned long long int v;
+ if (__riscv_hwprobe_one (hwprobe_func, RISCV_HWPROBE_KEY_IMA_EXT_0, &v) == 0
+ && (v & RISCV_HWPROBE_IMA_V) == RISCV_HWPROBE_IMA_V)
+ return __strcpy_vector;
+ return __strcpy_generic;
+}
+
+riscv_libc_ifunc (__libc_strcpy, select_strcpy_ifunc);
+
+# undef strcpy
+strong_alias (__libc_strcpy, strcpy);
+# ifdef SHARED
+__hidden_ver1 (strcpy, __GI_strcpy, __redirect_strcpy)
+ __attribute__ ((visibility ("hidden"))) __attribute_copy__ (strcpy);
+# endif
+#else
+# include <string/strcpy.c>
+#endif
--
2.47.3
More information about the Libc-alpha
mailing list