1 files changed, 33 insertions, 0 deletions
diff --git a/neozip/arch/riscv/slide_hash_rvv.c b/neozip/arch/riscv/slide_hash_rvv.c
new file mode 100644
index 0000000000..e794c38204
--- /dev/null
+++ b/neozip/arch/riscv/slide_hash_rvv.c
@@ -0,0 +1,33 @@
+/* slide_hash_rvv.c - RVV version of slide_hash
+ * Copyright (C) 2023 SiFive, Inc. All rights reserved.
+ * Contributed by Alex Chiang <alex.chiang@sifive.com>
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+#ifdef RISCV_RVV
+
+#include "zbuild.h"
+#include "deflate.h"
+
+#include <riscv_vector.h>
+
+static inline void slide_hash_chain(Pos *table, uint32_t entries, uint16_t wsize) {
+    size_t vl;
+    while (entries > 0) {
+        vl = __riscv_vsetvl_e16m4(entries);
+        vuint16m4_t v_tab = __riscv_vle16_v_u16m4(table, vl);
+        vuint16m4_t v_diff = __riscv_vssubu_vx_u16m4(v_tab, wsize, vl);
+        __riscv_vse16_v_u16m4(table, v_diff, vl);
+        table += vl, entries -= vl;
+    }
+}
+
+Z_INTERNAL void slide_hash_rvv(deflate_state *s) {
+    Assert(s->w_size <= UINT16_MAX, "w_size should fit in uint16_t");
+    uint16_t wsize = (uint16_t)s->w_size;
+
+    slide_hash_chain(s->head, HASH_SIZE, wsize);
+    slide_hash_chain(s->prev, wsize, wsize);
+}
+
+#endif // RISCV_RVV