[FFmpeg-devel] [PATCH] lavc/bswapdsp: add RV Zvbb bswap16 and bswap32

[Rémi Denis-Courmont]

---
 libavcodec/riscv/Makefile        |  1 +
 libavcodec/riscv/bswapdsp_init.c | 11 ++++++-
 libavcodec/riscv/bswapdsp_rvvb.S | 52 ++++++++++++++++++++++++++++++++
 3 files changed, 63 insertions(+), 1 deletion(-)
 create mode 100644 libavcodec/riscv/bswapdsp_rvvb.S

diff --git a/libavcodec/riscv/Makefile b/libavcodec/riscv/Makefile
index 0bbdd38116..8195c7a388 100644
--- a/libavcodec/riscv/Makefile
+++ b/libavcodec/riscv/Makefile
@@ -16,6 +16,7 @@ RVV-OBJS-$(CONFIG_BLOCKDSP) += riscv/blockdsp_rvv.o
 OBJS-$(CONFIG_BSWAPDSP) += riscv/bswapdsp_init.o
 RV-OBJS-$(CONFIG_BSWAPDSP) += riscv/bswapdsp_rvb.o
 RVV-OBJS-$(CONFIG_BSWAPDSP) += riscv/bswapdsp_rvv.o
+RVVB-OBJS-$(CONFIG_BSWAPDSP) += riscv/bswapdsp_rvvb.o
 OBJS-$(CONFIG_EXR_DECODER) += riscv/exrdsp_init.o
 RVV-OBJS-$(CONFIG_EXR_DECODER) += riscv/exrdsp_rvv.o
 OBJS-$(CONFIG_FLAC_DECODER) += riscv/flacdsp_init.o
diff --git a/libavcodec/riscv/bswapdsp_init.c b/libavcodec/riscv/bswapdsp_init.c
index d490c434e7..ce36d419d2 100644
--- a/libavcodec/riscv/bswapdsp_init.c
+++ b/libavcodec/riscv/bswapdsp_init.c
@@ -27,6 +27,8 @@
 
 void ff_bswap32_buf_rvb(uint32_t *dst, const uint32_t *src, int len);
 void ff_bswap16_buf_rvv(uint16_t *dst, const uint16_t *src, int len);
+void ff_bswap32_buf_rvvb(uint32_t *dst, const uint32_t *src, int len);
+void ff_bswap16_buf_rvvb(uint16_t *dst, const uint16_t *src, int len);
 
 av_cold void ff_bswapdsp_init_riscv(BswapDSPContext *c)
 {
@@ -39,8 +41,15 @@ av_cold void ff_bswapdsp_init_riscv(BswapDSPContext *c)
             c->bswap_buf = ff_bswap32_buf_rvb;
 #endif
 #if HAVE_RVV
-        if (flags & AV_CPU_FLAG_RVV_I32)
+        if (flags & AV_CPU_FLAG_RVV_I32) {
             c->bswap16_buf = ff_bswap16_buf_rvv;
+# if HAVE_RV_ZVBB
+            if (flags & AV_CPU_FLAG_RV_ZVBB) {
+                c->bswap_buf = ff_bswap32_buf_rvvb;
+                c->bswap16_buf = ff_bswap16_buf_rvvb;
+            }
+# endif
+        }
 #endif
     }
 #endif
diff --git a/libavcodec/riscv/bswapdsp_rvvb.S b/libavcodec/riscv/bswapdsp_rvvb.S
new file mode 100644
index 0000000000..165ac104a9
--- /dev/null
+++ b/libavcodec/riscv/bswapdsp_rvvb.S
@@ -0,0 +1,52 @@
+/*
+ * Copyright © 2024 Rémi Denis-Courmont.
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg 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.
+ *
+ * FFmpeg 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 FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "config.h"
+#include "libavutil/riscv/asm.S"
+
+func ff_bswap32_buf_rvvb, zve32x, zvbb, zba
+        lpad    0
+1:
+        vsetvli t0, a2, e32, m8, ta, ma
+        vle32.v v8, (a1)
+        sub     a2, a2, t0
+        vrev8.v v8, v8
+        sh2add  a1, t0, a1
+        vse32.v v8, (a0)
+        sh2add  a0, t0, a0
+        bnez    a2, 1b
+
+        ret
+endfunc
+
+func ff_bswap16_buf_rvvb, zve32x, zvbb, zba
+        lpad    0
+1:
+        vsetvli t0, a2, e16, m8, ta, ma
+        vle16.v v8, (a1)
+        sub     a2, a2, t0
+        vrev8.v v8, v8
+        sh1add  a1, t0, a1
+        vse16.v v8, (a0)
+        sh1add  a0, t0, a0
+        bnez    a2, 1b
+
+        ret
+endfunc
-- 
2.45.2