Add Neon implementation of aom_minmax_8x8
Add Neon implementation of aom_minmax_8x8 as well as the corresponding
tests.
Change-Id: Ic3cee438c2f28b9fc1dc06a09cc6c8a30a510026
diff --git a/aom_dsp/aom_dsp_rtcd_defs.pl b/aom_dsp/aom_dsp_rtcd_defs.pl
index d2efcaf..2580b3d 100755
--- a/aom_dsp/aom_dsp_rtcd_defs.pl
+++ b/aom_dsp/aom_dsp_rtcd_defs.pl
@@ -1206,7 +1206,7 @@
specialize qw/aom_avg_8x8_quad avx2 sse2 neon/;
add_proto qw/void aom_minmax_8x8/, "const uint8_t *s, int p, const uint8_t *d, int dp, int *min, int *max";
- specialize qw/aom_minmax_8x8 sse2/;
+ specialize qw/aom_minmax_8x8 sse2 neon/;
if (aom_config("CONFIG_AV1_HIGHBITDEPTH") eq "yes") {
add_proto qw/unsigned int aom_highbd_avg_8x8/, "const uint8_t *, int p";
diff --git a/aom_dsp/arm/avg_neon.c b/aom_dsp/arm/avg_neon.c
index 991fd3f..bac50ca 100644
--- a/aom_dsp/arm/avg_neon.c
+++ b/aom_dsp/arm/avg_neon.c
@@ -216,3 +216,57 @@
#endif
}
#endif // CONFIG_AV1_HIGHBITDEPTH
+
+void aom_minmax_8x8_neon(const uint8_t *a, int a_stride, const uint8_t *b,
+ int b_stride, int *min, int *max) {
+ // Load and concatenate.
+ const uint8x16_t a01 = load_u8_8x2(a + 0 * a_stride, a_stride);
+ const uint8x16_t a23 = load_u8_8x2(a + 2 * a_stride, a_stride);
+ const uint8x16_t a45 = load_u8_8x2(a + 4 * a_stride, a_stride);
+ const uint8x16_t a67 = load_u8_8x2(a + 6 * a_stride, a_stride);
+
+ const uint8x16_t b01 = load_u8_8x2(b + 0 * b_stride, b_stride);
+ const uint8x16_t b23 = load_u8_8x2(b + 2 * b_stride, b_stride);
+ const uint8x16_t b45 = load_u8_8x2(b + 4 * b_stride, b_stride);
+ const uint8x16_t b67 = load_u8_8x2(b + 6 * b_stride, b_stride);
+
+ // Absolute difference.
+ const uint8x16_t ab01_diff = vabdq_u8(a01, b01);
+ const uint8x16_t ab23_diff = vabdq_u8(a23, b23);
+ const uint8x16_t ab45_diff = vabdq_u8(a45, b45);
+ const uint8x16_t ab67_diff = vabdq_u8(a67, b67);
+
+ // Max values between the Q vectors.
+ const uint8x16_t ab0123_max = vmaxq_u8(ab01_diff, ab23_diff);
+ const uint8x16_t ab4567_max = vmaxq_u8(ab45_diff, ab67_diff);
+ const uint8x16_t ab0123_min = vminq_u8(ab01_diff, ab23_diff);
+ const uint8x16_t ab4567_min = vminq_u8(ab45_diff, ab67_diff);
+
+ const uint8x16_t ab07_max = vmaxq_u8(ab0123_max, ab4567_max);
+ const uint8x16_t ab07_min = vminq_u8(ab0123_min, ab4567_min);
+
+#if defined(__aarch64__)
+ *min = *max = 0; // Clear high bits
+ *((uint8_t *)max) = vmaxvq_u8(ab07_max);
+ *((uint8_t *)min) = vminvq_u8(ab07_min);
+#else
+ // Split into 64-bit vectors and execute pairwise min/max.
+ uint8x8_t ab_max = vmax_u8(vget_high_u8(ab07_max), vget_low_u8(ab07_max));
+ uint8x8_t ab_min = vmin_u8(vget_high_u8(ab07_min), vget_low_u8(ab07_min));
+
+ // Enough runs of vpmax/min propagate the max/min values to every position.
+ ab_max = vpmax_u8(ab_max, ab_max);
+ ab_min = vpmin_u8(ab_min, ab_min);
+
+ ab_max = vpmax_u8(ab_max, ab_max);
+ ab_min = vpmin_u8(ab_min, ab_min);
+
+ ab_max = vpmax_u8(ab_max, ab_max);
+ ab_min = vpmin_u8(ab_min, ab_min);
+
+ *min = *max = 0; // Clear high bits
+ // Store directly to avoid costly neon->gpr transfer.
+ vst1_lane_u8((uint8_t *)max, ab_max, 0);
+ vst1_lane_u8((uint8_t *)min, ab_min, 0);
+#endif
+}
diff --git a/test/minmax_test.cc b/test/minmax_test.cc
index 0a148d2..1ba1f9d 100644
--- a/test/minmax_test.cc
+++ b/test/minmax_test.cc
@@ -232,4 +232,9 @@
INSTANTIATE_TEST_SUITE_P(SSE2, MinMaxTest,
::testing::Values(&aom_minmax_8x8_sse2));
#endif
+
+#if HAVE_NEON
+INSTANTIATE_TEST_SUITE_P(NEON, MinMaxTest,
+ ::testing::Values(&aom_minmax_8x8_neon));
+#endif
} // namespace
