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Diffstat (limited to 'thirdparty/libwebp/dsp/dec_neon.c')
-rw-r--r--thirdparty/libwebp/dsp/dec_neon.c40
1 files changed, 20 insertions, 20 deletions
diff --git a/thirdparty/libwebp/dsp/dec_neon.c b/thirdparty/libwebp/dsp/dec_neon.c
index a63f43fe17..34796cf4a2 100644
--- a/thirdparty/libwebp/dsp/dec_neon.c
+++ b/thirdparty/libwebp/dsp/dec_neon.c
@@ -17,7 +17,7 @@
#if defined(WEBP_USE_NEON)
#include "./neon.h"
-#include "../dec/vp8i.h"
+#include "../dec/vp8i_dec.h"
//------------------------------------------------------------------------------
// NxM Loading functions
@@ -666,9 +666,8 @@ static uint8x16_t NeedsHev(const uint8x16_t p1, const uint8x16_t p0,
const uint8x16_t hev_thresh_v = vdupq_n_u8((uint8_t)hev_thresh);
const uint8x16_t a_p1_p0 = vabdq_u8(p1, p0); // abs(p1 - p0)
const uint8x16_t a_q1_q0 = vabdq_u8(q1, q0); // abs(q1 - q0)
- const uint8x16_t mask1 = vcgtq_u8(a_p1_p0, hev_thresh_v);
- const uint8x16_t mask2 = vcgtq_u8(a_q1_q0, hev_thresh_v);
- const uint8x16_t mask = vorrq_u8(mask1, mask2);
+ const uint8x16_t a_max = vmaxq_u8(a_p1_p0, a_q1_q0);
+ const uint8x16_t mask = vcgtq_u8(a_max, hev_thresh_v);
return mask;
}
@@ -756,24 +755,25 @@ static void ApplyFilter6(
const int8x16_t delta,
uint8x16_t* const op2, uint8x16_t* const op1, uint8x16_t* const op0,
uint8x16_t* const oq0, uint8x16_t* const oq1, uint8x16_t* const oq2) {
- const int16x8_t kCst63 = vdupq_n_s16(63);
- const int8x8_t kCst27 = vdup_n_s8(27);
- const int8x8_t kCst18 = vdup_n_s8(18);
- const int8x8_t kCst9 = vdup_n_s8(9);
+ // We have to compute: X = (9*a+63) >> 7, Y = (18*a+63)>>7, Z = (27*a+63) >> 7
+ // Turns out, there's a common sub-expression S=9 * a - 1 that can be used
+ // with the special vqrshrn_n_s16 rounding-shift-and-narrow instruction:
+ // X = (S + 64) >> 7, Y = (S + 32) >> 6, Z = (18 * a + S + 64) >> 7
const int8x8_t delta_lo = vget_low_s8(delta);
const int8x8_t delta_hi = vget_high_s8(delta);
- const int16x8_t s1_lo = vmlal_s8(kCst63, kCst27, delta_lo); // 63 + 27 * a
- const int16x8_t s1_hi = vmlal_s8(kCst63, kCst27, delta_hi); // 63 + 27 * a
- const int16x8_t s2_lo = vmlal_s8(kCst63, kCst18, delta_lo); // 63 + 18 * a
- const int16x8_t s2_hi = vmlal_s8(kCst63, kCst18, delta_hi); // 63 + 18 * a
- const int16x8_t s3_lo = vmlal_s8(kCst63, kCst9, delta_lo); // 63 + 9 * a
- const int16x8_t s3_hi = vmlal_s8(kCst63, kCst9, delta_hi); // 63 + 9 * a
- const int8x8_t a1_lo = vqshrn_n_s16(s1_lo, 7);
- const int8x8_t a1_hi = vqshrn_n_s16(s1_hi, 7);
- const int8x8_t a2_lo = vqshrn_n_s16(s2_lo, 7);
- const int8x8_t a2_hi = vqshrn_n_s16(s2_hi, 7);
- const int8x8_t a3_lo = vqshrn_n_s16(s3_lo, 7);
- const int8x8_t a3_hi = vqshrn_n_s16(s3_hi, 7);
+ const int8x8_t kCst9 = vdup_n_s8(9);
+ const int16x8_t kCstm1 = vdupq_n_s16(-1);
+ const int8x8_t kCst18 = vdup_n_s8(18);
+ const int16x8_t S_lo = vmlal_s8(kCstm1, kCst9, delta_lo); // S = 9 * a - 1
+ const int16x8_t S_hi = vmlal_s8(kCstm1, kCst9, delta_hi);
+ const int16x8_t Z_lo = vmlal_s8(S_lo, kCst18, delta_lo); // S + 18 * a
+ const int16x8_t Z_hi = vmlal_s8(S_hi, kCst18, delta_hi);
+ const int8x8_t a3_lo = vqrshrn_n_s16(S_lo, 7); // (9 * a + 63) >> 7
+ const int8x8_t a3_hi = vqrshrn_n_s16(S_hi, 7);
+ const int8x8_t a2_lo = vqrshrn_n_s16(S_lo, 6); // (9 * a + 31) >> 6
+ const int8x8_t a2_hi = vqrshrn_n_s16(S_hi, 6);
+ const int8x8_t a1_lo = vqrshrn_n_s16(Z_lo, 7); // (27 * a + 63) >> 7
+ const int8x8_t a1_hi = vqrshrn_n_s16(Z_hi, 7);
const int8x16_t a1 = vcombine_s8(a1_lo, a1_hi);
const int8x16_t a2 = vcombine_s8(a2_lo, a2_hi);
const int8x16_t a3 = vcombine_s8(a3_lo, a3_hi);