ac3enc: NEON optimised ac3_max_msb_abs_int16 and ac3_exponent_min

libavcodec/ac3dsp.c

@@ -109,6 +109,8 @@ av_cold void ff_ac3dsp_init(AC3DSPContext *c, int bit_exact)
     c->ac3_rshift_int32 = ac3_rshift_int32_c;
     c->float_to_fixed24 = float_to_fixed24_c;
 
+    if (ARCH_ARM)
+        ff_ac3dsp_init_arm(c, bit_exact);
     if (HAVE_MMX)
         ff_ac3dsp_init_x86(c, bit_exact);
 }

libavcodec/ac3dsp.h

@@ -84,6 +84,7 @@ typedef struct AC3DSPContext {
 } AC3DSPContext;
 
 void ff_ac3dsp_init    (AC3DSPContext *c, int bit_exact);
+void ff_ac3dsp_init_arm(AC3DSPContext *c, int bit_exact);
 void ff_ac3dsp_init_x86(AC3DSPContext *c, int bit_exact);
 
 #endif /* AVCODEC_AC3DSP_H */

libavcodec/arm/Makefile

+OBJS-$(CONFIG_AC3DSP)                  += arm/ac3dsp_init_arm.o
 OBJS-$(CONFIG_DCA_DECODER)             += arm/dcadsp_init_arm.o         \
 
 OBJS-$(CONFIG_VP5_DECODER)             += arm/vp56dsp_init_arm.o
@@ -46,6 +47,8 @@ NEON-OBJS-$(CONFIG_H264DSP)            += arm/h264dsp_neon.o            \
 
 NEON-OBJS-$(CONFIG_H264PRED)           += arm/h264pred_neon.o           \
 
+NEON-OBJS-$(CONFIG_AC3DSP)             += arm/ac3dsp_neon.o
+
 NEON-OBJS-$(CONFIG_DCA_DECODER)        += arm/dcadsp_neon.o             \
                                           arm/synth_filter_neon.o       \
 

libavcodec/arm/ac3dsp_init_arm.c

+/*
+ * Copyright (c) 2011 Mans Rullgard <mans@mansr.com>
+ *
+ * This file is part of Libav.
+ *
+ * Libav 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.
+ *
+ * Libav 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 Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <stdint.h>
+#include "libavutil/attributes.h"
+#include "libavcodec/ac3dsp.h"
+#include "config.h"
+
+void ff_ac3_exponent_min_neon(uint8_t *exp, int num_reuse_blocks, int nb_coefs);
+int ff_ac3_max_msb_abs_int16_neon(const int16_t *src, int len);
+
+av_cold void ff_ac3dsp_init_arm(AC3DSPContext *c, int bit_exact)
+{
+    if (HAVE_NEON) {
+        c->ac3_exponent_min      = ff_ac3_exponent_min_neon;
+        c->ac3_max_msb_abs_int16 = ff_ac3_max_msb_abs_int16_neon;
+    }
+}

libavcodec/arm/ac3dsp_neon.S

+/*
+ * Copyright (c) 2011 Mans Rullgard <mans@mansr.com>
+ *
+ * This file is part of Libav.
+ *
+ * Libav 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.
+ *
+ * Libav 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 Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "asm.S"
+
+function ff_ac3_max_msb_abs_int16_neon, export=1
+        vmov.i16        q0,  #0
+        vmov.i16        q2,  #0
+1:      vld1.16         {q1},     [r0,:128]!
+        vabs.s16        q1,  q1
+        vld1.16         {q3},     [r0,:128]!
+        vabs.s16        q3,  q3
+        vorr            q0,  q0,  q1
+        vorr            q2,  q2,  q3
+        subs            r1,  r1,  #16
+        bgt             1b
+        vorr            q0,  q0,  q2
+        vorr            d0,  d0,  d1
+        vpmax.u16       d0,  d0,  d0
+        vpmax.u16       d0,  d0,  d0
+        vmov.u16        r0,  d0[0]
+        bx              lr
+endfunc
+
+function ff_ac3_exponent_min_neon, export=1
+        cmp             r1,  #0
+        bxeq            lr
+        push            {lr}
+        mov             r12, #256
+1:
+        vld1.8          {q0},     [r0,:128]
+        mov             lr,  r1
+        add             r3,  r0,  #256
+2:      vld1.8          {q1},     [r3,:128], r12
+        subs            lr,  lr,  #1
+        vmin.u8         q0,  q0,  q1
+        bgt             2b
+        subs            r2,  r2,  #16
+        vst1.8          {q0},     [r0,:128]!
+        bgt             1b
+        pop             {pc}
+endfunc