remove unused aom_get4x4sse_cs

this was inherited from libvpx (VP8), is unused in the library and only
called from variance_test.cc

Bug: aomedia:3416
Change-Id: I475774a5d72862ed51411ce4886b93ac8a0dbd61
diff --git a/aom_dsp/aom_dsp_rtcd_defs.pl b/aom_dsp/aom_dsp_rtcd_defs.pl
index 060a5a1..baea019 100755
--- a/aom_dsp/aom_dsp_rtcd_defs.pl
+++ b/aom_dsp/aom_dsp_rtcd_defs.pl
@@ -1342,10 +1342,7 @@
   #
   #
   add_proto qw/unsigned int aom_get_mb_ss/, "const int16_t *";
-  add_proto qw/unsigned int aom_get4x4sse_cs/, "const unsigned char *src_ptr, int source_stride, const unsigned char *ref_ptr, int ref_stride";
-
   specialize qw/aom_get_mb_ss sse2/;
-  specialize qw/aom_get4x4sse_cs neon/;
 
   #
   # Variance / Subpixel Variance / Subpixel Avg Variance
diff --git a/aom_dsp/arm/variance_neon.c b/aom_dsp/arm/variance_neon.c
index 5c25861..0d6fe16 100644
--- a/aom_dsp/arm/variance_neon.c
+++ b/aom_dsp/arm/variance_neon.c
@@ -476,18 +476,6 @@
   return horizontal_add_u32x4(vaddq_u32(sse_u32[0], sse_u32[1]));
 }
 
-unsigned int aom_get4x4sse_cs_neon(const uint8_t *src, int src_stride,
-                                   const uint8_t *ref, int ref_stride) {
-  uint8x16_t s = load_unaligned_u8q(src, src_stride);
-  uint8x16_t r = load_unaligned_u8q(ref, ref_stride);
-
-  uint8x16_t abs_diff = vabdq_u8(s, r);
-
-  uint32x4_t sse = vdotq_u32(vdupq_n_u32(0), abs_diff, abs_diff);
-
-  return horizontal_add_u32x4(sse);
-}
-
 #else  // !defined(__ARM_FEATURE_DOTPROD)
 
 static INLINE unsigned int mse8xh_neon(const uint8_t *src, int src_stride,
@@ -587,30 +575,6 @@
   return horizontal_add_u32x4(vreinterpretq_u32_s32(sse_s32[0]));
 }
 
-unsigned int aom_get4x4sse_cs_neon(const uint8_t *src, int src_stride,
-                                   const uint8_t *ref, int ref_stride) {
-  uint8x8_t s[2], r[2];
-  uint16x8_t abs_diff[2];
-  uint32x4_t sse;
-
-  s[0] = load_u8(src, src_stride);
-  r[0] = load_u8(ref, ref_stride);
-  src += 2 * src_stride;
-  ref += 2 * ref_stride;
-  s[1] = load_u8(src, src_stride);
-  r[1] = load_u8(ref, ref_stride);
-
-  abs_diff[0] = vabdl_u8(s[0], r[0]);
-  abs_diff[1] = vabdl_u8(s[1], r[1]);
-
-  sse = vmull_u16(vget_low_u16(abs_diff[0]), vget_low_u16(abs_diff[0]));
-  sse = vmlal_u16(sse, vget_high_u16(abs_diff[0]), vget_high_u16(abs_diff[0]));
-  sse = vmlal_u16(sse, vget_low_u16(abs_diff[1]), vget_low_u16(abs_diff[1]));
-  sse = vmlal_u16(sse, vget_high_u16(abs_diff[1]), vget_high_u16(abs_diff[1]));
-
-  return horizontal_add_u32x4(sse);
-}
-
 #endif  // defined(__ARM_FEATURE_DOTPROD)
 
 #define MSE_WXH_NEON(w, h)                                                 \
diff --git a/aom_dsp/variance.c b/aom_dsp/variance.c
index 7b28844..443aea4 100644
--- a/aom_dsp/variance.c
+++ b/aom_dsp/variance.c
@@ -25,24 +25,6 @@
 #include "av1/common/filter.h"
 #include "av1/common/reconinter.h"
 
-uint32_t aom_get4x4sse_cs_c(const uint8_t *a, int a_stride, const uint8_t *b,
-                            int b_stride) {
-  int distortion = 0;
-  int r, c;
-
-  for (r = 0; r < 4; ++r) {
-    for (c = 0; c < 4; ++c) {
-      int diff = a[c] - b[c];
-      distortion += diff * diff;
-    }
-
-    a += a_stride;
-    b += b_stride;
-  }
-
-  return distortion;
-}
-
 uint32_t aom_get_mb_ss_c(const int16_t *a) {
   unsigned int i, sum = 0;
 
diff --git a/test/variance_test.cc b/test/variance_test.cc
index 93c2e2f..ce5afec 100644
--- a/test/variance_test.cc
+++ b/test/variance_test.cc
@@ -56,8 +56,6 @@
                                             const uint8_t *b, int b_stride,
                                             uint32_t *sse,
                                             const uint8_t *second_pred);
-typedef unsigned int (*Get4x4SseFunc)(const uint8_t *a, int a_stride,
-                                      const uint8_t *b, int b_stride);
 typedef unsigned int (*SumOfSquaresFunction)(const int16_t *src);
 typedef unsigned int (*DistWtdSubpixAvgVarMxNFunc)(
     const uint8_t *a, int a_stride, int xoffset, int yoffset, const uint8_t *b,
@@ -1672,7 +1670,6 @@
 
 typedef MseWxHTestClass<MseWxH16bitFunc> MseWxHTest;
 typedef Mse16xHTestClass<Mse16xH16bitFunc> Mse16xHTest;
-typedef MainTestClass<Get4x4SseFunc> AvxSseTest;
 typedef MainTestClass<VarianceMxNFunc> AvxMseTest;
 typedef MainTestClass<VarianceMxNFunc> AvxVarianceTest;
 typedef MainTestClass<GetSseSum8x8QuadFunc> GetSseSum8x8QuadTest;
@@ -1687,8 +1684,6 @@
 typedef TestParams<MseWxH16bitFunc> MseWxHParams;
 typedef TestParams<Mse16xH16bitFunc> Mse16xHParams;
 
-TEST_P(AvxSseTest, RefSse) { RefTestSse(); }
-TEST_P(AvxSseTest, MaxSse) { MaxTestSse(); }
 TEST_P(MseWxHTest, RefMse) { RefMatchTestMse(); }
 TEST_P(MseWxHTest, DISABLED_SpeedMse) { SpeedTest(); }
 TEST_P(Mse16xHTest, RefMse) { RefMatchTestMse(); }
@@ -1739,11 +1734,6 @@
 INSTANTIATE_TEST_SUITE_P(C, SumOfSquaresTest,
                          ::testing::Values(aom_get_mb_ss_c));
 
-typedef TestParams<Get4x4SseFunc> SseParams;
-INSTANTIATE_TEST_SUITE_P(C, AvxSseTest,
-                         ::testing::Values(SseParams(2, 2,
-                                                     &aom_get4x4sse_cs_c)));
-
 typedef TestParams<VarianceMxNFunc> MseParams;
 INSTANTIATE_TEST_SUITE_P(C, AvxMseTest,
                          ::testing::Values(MseParams(4, 4, &aom_mse16x16_c),
@@ -3225,10 +3215,6 @@
                       MseWxHParams(2, 3, &aom_mse_wxh_16bit_neon, 8),
                       MseWxHParams(2, 2, &aom_mse_wxh_16bit_neon, 8)));
 
-INSTANTIATE_TEST_SUITE_P(NEON, AvxSseTest,
-                         ::testing::Values(SseParams(2, 2,
-                                                     &aom_get4x4sse_cs_neon)));
-
 INSTANTIATE_TEST_SUITE_P(NEON, AvxMseTest,
                          ::testing::Values(MseParams(3, 3, &aom_mse8x8_neon),
                                            MseParams(3, 4, &aom_mse8x16_neon),