From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ffbox0-bg.mplayerhq.hu (ffbox0-bg.ffmpeg.org [79.124.17.100]) by master.gitmailbox.com (Postfix) with ESMTP id 5E37D46ED5 for ; Sun, 16 Jul 2023 15:14:08 +0000 (UTC) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id 8C4D768C699; Sun, 16 Jul 2023 18:14:00 +0300 (EEST) Received: from ursule.remlab.net (vps-a2bccee9.vps.ovh.net [51.75.19.47]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id 4CDBE68C4C1 for ; Sun, 16 Jul 2023 18:13:53 +0300 (EEST) Received: from basile.remlab.net (localhost [IPv6:::1]) by ursule.remlab.net (Postfix) with ESMTP id D734CC00C0 for ; Sun, 16 Jul 2023 18:13:52 +0300 (EEST) From: =?UTF-8?q?R=C3=A9mi=20Denis-Courmont?= To: ffmpeg-devel@ffmpeg.org Date: Sun, 16 Jul 2023 18:13:52 +0300 Message-Id: <20230716151352.121105-2-remi@remlab.net> X-Mailer: git-send-email 2.40.1 MIME-Version: 1.0 Subject: [FFmpeg-devel] [PATCH 2/2] lavc/bswapdsp: purge RISC-V V bswap32 X-BeenThere: ffmpeg-devel@ffmpeg.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: FFmpeg development discussions and patches List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: FFmpeg development discussions and patches Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: ffmpeg-devel-bounces@ffmpeg.org Sender: "ffmpeg-devel" Archived-At: List-Archive: List-Post: This cannot beat the Zbb implementation, and it is unlikely that a real meaningful CPU design would support V and not Zbb. The best loop rewrite that I could come up with (4 shifts, 2 ands, 3 ors) is still ~40% slower than Zbb. A proper faster vector implementation should be feasible with the cryptographic vector extensions, but that is a story for another time. --- libavcodec/riscv/bswapdsp_init.c | 5 +---- libavcodec/riscv/bswapdsp_rvv.S | 23 ----------------------- 2 files changed, 1 insertion(+), 27 deletions(-) diff --git a/libavcodec/riscv/bswapdsp_init.c b/libavcodec/riscv/bswapdsp_init.c index 6ad63e3805..ed666c9b3a 100644 --- a/libavcodec/riscv/bswapdsp_init.c +++ b/libavcodec/riscv/bswapdsp_init.c @@ -26,7 +26,6 @@ #include "libavcodec/bswapdsp.h" void ff_bswap32_buf_rvb(uint32_t *dst, const uint32_t *src, int len); -void ff_bswap32_buf_rvv(uint32_t *dst, const uint32_t *src, int len); void ff_bswap16_buf_rvv(uint16_t *dst, const uint16_t *src, int len); av_cold void ff_bswapdsp_init_riscv(BswapDSPContext *c) @@ -39,10 +38,8 @@ 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) { - c->bswap_buf = ff_bswap32_buf_rvv; + if (flags & AV_CPU_FLAG_RVV_I32) c->bswap16_buf = ff_bswap16_buf_rvv; - } #endif } } diff --git a/libavcodec/riscv/bswapdsp_rvv.S b/libavcodec/riscv/bswapdsp_rvv.S index 8b585ec5c9..b37fe26255 100644 --- a/libavcodec/riscv/bswapdsp_rvv.S +++ b/libavcodec/riscv/bswapdsp_rvv.S @@ -21,29 +21,6 @@ #include "config.h" #include "libavutil/riscv/asm.S" -func ff_bswap32_buf_rvv, zve32x - li t4, 4 - addi t1, a0, 1 - addi t2, a0, 2 - addi t3, a0, 3 -1: - vsetvli t0, a2, e8, m1, ta, ma - vlseg4e8.v v8, (a1) - sub a2, a2, t0 - sh2add a1, t0, a1 - vsse8.v v8, (t3), t4 - sh2add t3, t0, t3 - vsse8.v v9, (t2), t4 - sh2add t2, t0, t2 - vsse8.v v10, (t1), t4 - sh2add t1, t0, t1 - vsse8.v v11, (a0), t4 - sh2add a0, t0, a0 - bnez a2, 1b - - ret -endfunc - func ff_bswap16_buf_rvv, zve32x 1: vsetvli t0, a2, e16, m8, ta, ma -- 2.40.1 _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".