From 7901e7216cf6406a2ea430c71af94ebee72f262b Mon Sep 17 00:00:00 2001
From: Ben Avison <bavison@riscosopen.org>
Date: Mon, 15 Jul 2013 18:28:11 +0100
Subject: [PATCH 41/49] [ffmpeg] - backport - fmtconvert: Add a new method,
 int32_to_float_fmul_array8
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This is similar to int32_to_float_fmul_scalar, but
loads a new scalar multiplier every 8 input samples.
This enables the use of much larger input arrays, which
is important for pipelining on some CPUs (such as
ARMv6).

Signed-off-by: Martin Storsjö <martin@martin.st>
---
 lib/ffmpeg/libavcodec/fmtconvert.c |   10 ++++++++++
 lib/ffmpeg/libavcodec/fmtconvert.h |   16 ++++++++++++++++
 2 files changed, 26 insertions(+)

diff --git a/lib/ffmpeg/libavcodec/fmtconvert.c b/lib/ffmpeg/libavcodec/fmtconvert.c
index 79e9645..1c45d35 100644
--- a/lib/ffmpeg/libavcodec/fmtconvert.c
+++ b/lib/ffmpeg/libavcodec/fmtconvert.c
@@ -30,6 +30,15 @@ static void int32_to_float_fmul_scalar_c(float *dst, const int *src, float mul,
         dst[i] = src[i] * mul;
 }

+static void int32_to_float_fmul_array8_c(FmtConvertContext *c, float *dst,
+                                         const int32_t *src, const float *mul,
+                                         int len)
+{
+    int i;
+    for (i = 0; i < len; i += 8)
+        c->int32_to_float_fmul_scalar(&dst[i], &src[i], *mul++, 8);
+}
+
 static av_always_inline int float_to_int16_one(const float *src){
     return av_clip_int16(lrintf(*src));
 }
@@ -79,6 +88,7 @@ void ff_float_interleave_c(float *dst, const float **src, unsigned int len,
 av_cold void ff_fmt_convert_init(FmtConvertContext *c, AVCodecContext *avctx)
 {
     c->int32_to_float_fmul_scalar = int32_to_float_fmul_scalar_c;
+    c->int32_to_float_fmul_array8 = int32_to_float_fmul_array8_c;
     c->float_to_int16             = float_to_int16_c;
     c->float_to_int16_interleave  = float_to_int16_interleave_c;
     c->float_interleave           = ff_float_interleave_c;
diff --git a/lib/ffmpeg/libavcodec/fmtconvert.h b/lib/ffmpeg/libavcodec/fmtconvert.h
index 3fb9f4e..02468dc 100644
--- a/lib/ffmpeg/libavcodec/fmtconvert.h
+++ b/lib/ffmpeg/libavcodec/fmtconvert.h
@@ -38,6 +38,22 @@ typedef struct FmtConvertContext {
     void (*int32_to_float_fmul_scalar)(float *dst, const int *src, float mul, int len);

     /**
+     * Convert an array of int32_t to float and multiply by a float value from another array,
+     * stepping along the float array once for each 8 integers.
+     * @param c   pointer to FmtConvertContext.
+     * @param dst destination array of float.
+     *            constraints: 16-byte aligned
+     * @param src source array of int32_t.
+     *            constraints: 16-byte aligned
+     * @param mul source array of float multipliers.
+     * @param len number of elements to convert.
+     *            constraints: multiple of 8
+     */
+    void (*int32_to_float_fmul_array8)(struct FmtConvertContext *c,
+                                       float *dst, const int32_t *src,
+                                       const float *mul, int len);
+
+    /**
      * Convert an array of float to an array of int16_t.
      *
      * Convert floats from in the range [-32768.0,32767.0] to ints
--
1.7.9.5
