ac3enc: ARM optimised ac3_compute_matissa_size

Signed-off-by: Mans Rullgard <mans@mansr.com>

libavcodec/arm/Makefile

@@ -1,4 +1,6 @@
-OBJS-$(CONFIG_AC3DSP)                  += arm/ac3dsp_init_arm.o
+OBJS-$(CONFIG_AC3DSP)                  += arm/ac3dsp_init_arm.o         \
+                                          arm/ac3dsp_arm.o
+
 OBJS-$(CONFIG_DCA_DECODER)             += arm/dcadsp_init_arm.o         \
 
 ARMV6-OBJS-$(CONFIG_AC3DSP)            += arm/ac3dsp_armv6.o

libavcodec/arm/ac3dsp_arm.S

@@ -0,0 +1,52 @@
+/*
+ * 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_compute_mantissa_size_arm, export=1
+        push            {r4-r8,lr}
+        ldm             r0,  {r4-r8}
+        mov             r3,  r0
+        mov             r0,  #0
+1:
+        ldrb            lr,  [r1], #1
+        subs            r2,  r2,  #1
+        blt             2f
+        cmp             lr,  #4
+        bgt             3f
+        subs            lr,  lr,  #1
+        addlt           r4,  r4,  #1
+        addeq           r5,  r5,  #1
+        ble             1b
+        subs            lr,  lr,  #2
+        addlt           r6,  r6,  #1
+        addeq           r7,  r7,  #1
+        addgt           r8,  r8,  #1
+        b               1b
+3:
+        cmp             lr,  #14
+        sublt           lr,  lr,  #1
+        addgt           r0,  r0,  #16
+        addle           r0,  r0,  lr
+        b               1b
+2:
+        stm             r3,  {r4-r8}
+        pop             {r4-r8,pc}
+endfunc

libavcodec/arm/ac3dsp_init_arm.c

@@ -34,8 +34,12 @@ void ff_ac3_bit_alloc_calc_bap_armv6(int16_t *mask, int16_t *psd,
                                      int snr_offset, int floor,
                                      const uint8_t *bap_tab, uint8_t *bap);
 
+int ff_ac3_compute_mantissa_size_arm(int cnt[5], uint8_t *bap, int nb_coefs);
+
 av_cold void ff_ac3dsp_init_arm(AC3DSPContext *c, int bit_exact)
 {
+    c->compute_mantissa_size     = ff_ac3_compute_mantissa_size_arm;
+
     if (HAVE_ARMV6) {
         c->bit_alloc_calc_bap    = ff_ac3_bit_alloc_calc_bap_armv6;
     }