ref: ca2601262a05ba7aa30103df163c5c3b9e32a7b1
dir: /vpx_dsp/ppc/quantize_vsx.c/
/* * Copyright (c) 2018 The WebM project authors. All Rights Reserved. * * Use of this source code is governed by a BSD-style license * that can be found in the LICENSE file in the root of the source * tree. An additional intellectual property rights grant can be found * in the file PATENTS. All contributing project authors may * be found in the AUTHORS file in the root of the source tree. */ #include <assert.h> #include "./vpx_dsp_rtcd.h" #include "vpx_dsp/ppc/types_vsx.h" // Negate 16-bit integers in a when the corresponding signed 16-bit // integer in b is negative. static INLINE int16x8_t vec_sign(int16x8_t a, int16x8_t b) { const int16x8_t mask = vec_sra(b, vec_shift_sign_s16); return vec_xor(vec_add(a, mask), mask); } // Sets the value of a 32-bit integers to 1 when the corresponding value in a is // negative. static INLINE int32x4_t vec_is_neg(int32x4_t a) { return vec_sr(a, vec_shift_sign_s32); } // Multiply the packed 16-bit integers in a and b, producing intermediate 32-bit // integers, and return the high 16 bits of the intermediate integers. // (a * b) >> 16 static INLINE int16x8_t vec_mulhi(int16x8_t a, int16x8_t b) { // madds does ((A * B) >>15) + C, we need >> 16, so we perform an extra right // shift. return vec_sra(vec_madds(a, b, vec_zeros_s16), vec_ones_u16); } // Quantization function used for 4x4, 8x8 and 16x16 blocks. static INLINE int16x8_t quantize_coeff(int16x8_t coeff, int16x8_t coeff_abs, int16x8_t round, int16x8_t quant, int16x8_t quant_shift, bool16x8_t mask) { const int16x8_t rounded = vec_vaddshs(coeff_abs, round); int16x8_t qcoeff = vec_mulhi(rounded, quant); qcoeff = vec_add(qcoeff, rounded); qcoeff = vec_mulhi(qcoeff, quant_shift); qcoeff = vec_sign(qcoeff, coeff); return vec_and(qcoeff, mask); } // Quantization function used for 32x32 blocks. static INLINE int16x8_t quantize_coeff_32(int16x8_t coeff, int16x8_t coeff_abs, int16x8_t round, int16x8_t quant, int16x8_t quant_shift, bool16x8_t mask) { const int16x8_t rounded = vec_vaddshs(coeff_abs, round); int16x8_t qcoeff = vec_mulhi(rounded, quant); qcoeff = vec_add(qcoeff, rounded); // 32x32 blocks require an extra multiplication by 2, this compensates for the // extra right shift added in vec_mulhi, as such vec_madds can be used // directly instead of vec_mulhi (((a * b) >> 15) >> 1) << 1 == (a * b >> 15) qcoeff = vec_madds(qcoeff, quant_shift, vec_zeros_s16); qcoeff = vec_sign(qcoeff, coeff); return vec_and(qcoeff, mask); } // DeQuantization function used for 32x32 blocks. Quantized coeff of 32x32 // blocks are twice as big as for other block sizes. As such, using // vec_mladd results in overflow. static INLINE int16x8_t dequantize_coeff_32(int16x8_t qcoeff, int16x8_t dequant) { int32x4_t dqcoeffe = vec_mule(qcoeff, dequant); int32x4_t dqcoeffo = vec_mulo(qcoeff, dequant); // Add 1 if negative to round towards zero because the C uses division. dqcoeffe = vec_add(dqcoeffe, vec_is_neg(dqcoeffe)); dqcoeffo = vec_add(dqcoeffo, vec_is_neg(dqcoeffo)); dqcoeffe = vec_sra(dqcoeffe, vec_ones_u32); dqcoeffo = vec_sra(dqcoeffo, vec_ones_u32); return (int16x8_t)vec_perm(dqcoeffe, dqcoeffo, vec_perm_odd_even_pack); } static INLINE int16x8_t nonzero_scanindex(int16x8_t qcoeff, bool16x8_t mask, const int16_t *iscan_ptr, int index) { int16x8_t scan = vec_vsx_ld(index, iscan_ptr); bool16x8_t zero_coeff = vec_cmpeq(qcoeff, vec_zeros_s16); scan = vec_sub(scan, mask); return vec_andc(scan, zero_coeff); } // Compare packed 16-bit integers across a, and return the maximum value in // every element. Returns a vector containing the biggest value across vector a. static INLINE int16x8_t vec_max_across(int16x8_t a) { a = vec_max(a, vec_perm(a, a, vec_perm64)); a = vec_max(a, vec_perm(a, a, vec_perm32)); return vec_max(a, vec_perm(a, a, vec_perm16)); } void vpx_quantize_b_vsx(const tran_low_t *coeff_ptr, intptr_t n_coeffs, int skip_block, const int16_t *zbin_ptr, const int16_t *round_ptr, const int16_t *quant_ptr, const int16_t *quant_shift_ptr, tran_low_t *qcoeff_ptr, tran_low_t *dqcoeff_ptr, const int16_t *dequant_ptr, uint16_t *eob_ptr, const int16_t *scan_ptr, const int16_t *iscan_ptr) { int16x8_t qcoeff0, qcoeff1, dqcoeff0, dqcoeff1, eob; bool16x8_t zero_mask0, zero_mask1; // First set of 8 coeff starts with DC + 7 AC int16x8_t zbin = vec_vsx_ld(0, zbin_ptr); int16x8_t round = vec_vsx_ld(0, round_ptr); int16x8_t quant = vec_vsx_ld(0, quant_ptr); int16x8_t dequant = vec_vsx_ld(0, dequant_ptr); int16x8_t quant_shift = vec_vsx_ld(0, quant_shift_ptr); int16x8_t coeff0 = vec_vsx_ld(0, coeff_ptr); int16x8_t coeff1 = vec_vsx_ld(16, coeff_ptr); int16x8_t coeff0_abs = vec_abs(coeff0); int16x8_t coeff1_abs = vec_abs(coeff1); zero_mask0 = vec_cmpge(coeff0_abs, zbin); zbin = vec_splat(zbin, 1); zero_mask1 = vec_cmpge(coeff1_abs, zbin); (void)scan_ptr; (void)skip_block; assert(!skip_block); qcoeff0 = quantize_coeff(coeff0, coeff0_abs, round, quant, quant_shift, zero_mask0); vec_vsx_st(qcoeff0, 0, qcoeff_ptr); round = vec_splat(round, 1); quant = vec_splat(quant, 1); quant_shift = vec_splat(quant_shift, 1); qcoeff1 = quantize_coeff(coeff1, coeff1_abs, round, quant, quant_shift, zero_mask1); vec_vsx_st(qcoeff1, 16, qcoeff_ptr); dqcoeff0 = vec_mladd(qcoeff0, dequant, vec_zeros_s16); vec_vsx_st(dqcoeff0, 0, dqcoeff_ptr); dequant = vec_splat(dequant, 1); dqcoeff1 = vec_mladd(qcoeff1, dequant, vec_zeros_s16); vec_vsx_st(dqcoeff1, 16, dqcoeff_ptr); eob = vec_max(nonzero_scanindex(qcoeff0, zero_mask0, iscan_ptr, 0), nonzero_scanindex(qcoeff1, zero_mask1, iscan_ptr, 16)); if (n_coeffs > 16) { int index = 16; int off0 = 32; int off1 = 48; int off2 = 64; do { int16x8_t coeff2, coeff2_abs, qcoeff2, dqcoeff2, eob2; bool16x8_t zero_mask2; coeff0 = vec_vsx_ld(off0, coeff_ptr); coeff1 = vec_vsx_ld(off1, coeff_ptr); coeff2 = vec_vsx_ld(off2, coeff_ptr); coeff0_abs = vec_abs(coeff0); coeff1_abs = vec_abs(coeff1); coeff2_abs = vec_abs(coeff2); zero_mask0 = vec_cmpge(coeff0_abs, zbin); zero_mask1 = vec_cmpge(coeff1_abs, zbin); zero_mask2 = vec_cmpge(coeff2_abs, zbin); qcoeff0 = quantize_coeff(coeff0, coeff0_abs, round, quant, quant_shift, zero_mask0); qcoeff1 = quantize_coeff(coeff1, coeff1_abs, round, quant, quant_shift, zero_mask1); qcoeff2 = quantize_coeff(coeff2, coeff2_abs, round, quant, quant_shift, zero_mask2); vec_vsx_st(qcoeff0, off0, qcoeff_ptr); vec_vsx_st(qcoeff1, off1, qcoeff_ptr); vec_vsx_st(qcoeff2, off2, qcoeff_ptr); dqcoeff0 = vec_mladd(qcoeff0, dequant, vec_zeros_s16); dqcoeff1 = vec_mladd(qcoeff1, dequant, vec_zeros_s16); dqcoeff2 = vec_mladd(qcoeff2, dequant, vec_zeros_s16); vec_vsx_st(dqcoeff0, off0, dqcoeff_ptr); vec_vsx_st(dqcoeff1, off1, dqcoeff_ptr); vec_vsx_st(dqcoeff2, off2, dqcoeff_ptr); eob = vec_max(eob, nonzero_scanindex(qcoeff0, zero_mask0, iscan_ptr, off0)); eob2 = vec_max(nonzero_scanindex(qcoeff1, zero_mask1, iscan_ptr, off1), nonzero_scanindex(qcoeff2, zero_mask2, iscan_ptr, off2)); eob = vec_max(eob, eob2); index += 24; off0 += 48; off1 += 48; off2 += 48; } while (index < n_coeffs); } eob = vec_max_across(eob); *eob_ptr = eob[0]; } void vpx_quantize_b_32x32_vsx( const tran_low_t *coeff_ptr, intptr_t n_coeffs, int skip_block, const int16_t *zbin_ptr, const int16_t *round_ptr, const int16_t *quant_ptr, const int16_t *quant_shift_ptr, tran_low_t *qcoeff_ptr, tran_low_t *dqcoeff_ptr, const int16_t *dequant_ptr, uint16_t *eob_ptr, const int16_t *scan_ptr, const int16_t *iscan_ptr) { // In stage 1, we quantize 16 coeffs (DC + 15 AC) // In stage 2, we loop 42 times and quantize 24 coeffs per iteration // (32 * 32 - 16) / 24 = 42 int num_itr = 42; // Offsets are in bytes, 16 coeffs = 32 bytes int off0 = 32; int off1 = 48; int off2 = 64; int16x8_t qcoeff0, qcoeff1, eob; bool16x8_t zero_mask0, zero_mask1; int16x8_t zbin = vec_vsx_ld(0, zbin_ptr); int16x8_t round = vec_vsx_ld(0, round_ptr); int16x8_t quant = vec_vsx_ld(0, quant_ptr); int16x8_t dequant = vec_vsx_ld(0, dequant_ptr); int16x8_t quant_shift = vec_vsx_ld(0, quant_shift_ptr); int16x8_t coeff0 = vec_vsx_ld(0, coeff_ptr); int16x8_t coeff1 = vec_vsx_ld(16, coeff_ptr); int16x8_t coeff0_abs = vec_abs(coeff0); int16x8_t coeff1_abs = vec_abs(coeff1); (void)scan_ptr; (void)skip_block; (void)n_coeffs; assert(!skip_block); // 32x32 quantization requires that zbin and round be divided by 2 zbin = vec_sra(vec_add(zbin, vec_ones_s16), vec_ones_u16); round = vec_sra(vec_add(round, vec_ones_s16), vec_ones_u16); zero_mask0 = vec_cmpge(coeff0_abs, zbin); zbin = vec_splat(zbin, 1); // remove DC from zbin zero_mask1 = vec_cmpge(coeff1_abs, zbin); qcoeff0 = quantize_coeff_32(coeff0, coeff0_abs, round, quant, quant_shift, zero_mask0); round = vec_splat(round, 1); // remove DC from round quant = vec_splat(quant, 1); // remove DC from quant quant_shift = vec_splat(quant_shift, 1); // remove DC from quant_shift qcoeff1 = quantize_coeff_32(coeff1, coeff1_abs, round, quant, quant_shift, zero_mask1); vec_vsx_st(qcoeff0, 0, qcoeff_ptr); vec_vsx_st(qcoeff1, 16, qcoeff_ptr); vec_vsx_st(dequantize_coeff_32(qcoeff0, dequant), 0, dqcoeff_ptr); dequant = vec_splat(dequant, 1); // remove DC from dequant vec_vsx_st(dequantize_coeff_32(qcoeff1, dequant), 16, dqcoeff_ptr); eob = vec_max(nonzero_scanindex(qcoeff0, zero_mask0, iscan_ptr, 0), nonzero_scanindex(qcoeff1, zero_mask1, iscan_ptr, 16)); do { int16x8_t coeff2, coeff2_abs, qcoeff2, eob2; bool16x8_t zero_mask2; coeff0 = vec_vsx_ld(off0, coeff_ptr); coeff1 = vec_vsx_ld(off1, coeff_ptr); coeff2 = vec_vsx_ld(off2, coeff_ptr); coeff0_abs = vec_abs(coeff0); coeff1_abs = vec_abs(coeff1); coeff2_abs = vec_abs(coeff2); zero_mask0 = vec_cmpge(coeff0_abs, zbin); zero_mask1 = vec_cmpge(coeff1_abs, zbin); zero_mask2 = vec_cmpge(coeff2_abs, zbin); qcoeff0 = quantize_coeff_32(coeff0, coeff0_abs, round, quant, quant_shift, zero_mask0); qcoeff1 = quantize_coeff_32(coeff1, coeff1_abs, round, quant, quant_shift, zero_mask1); qcoeff2 = quantize_coeff_32(coeff2, coeff2_abs, round, quant, quant_shift, zero_mask2); vec_vsx_st(qcoeff0, off0, qcoeff_ptr); vec_vsx_st(qcoeff1, off1, qcoeff_ptr); vec_vsx_st(qcoeff2, off2, qcoeff_ptr); vec_vsx_st(dequantize_coeff_32(qcoeff0, dequant), off0, dqcoeff_ptr); vec_vsx_st(dequantize_coeff_32(qcoeff1, dequant), off1, dqcoeff_ptr); vec_vsx_st(dequantize_coeff_32(qcoeff2, dequant), off2, dqcoeff_ptr); eob = vec_max(eob, nonzero_scanindex(qcoeff0, zero_mask0, iscan_ptr, off0)); eob2 = vec_max(nonzero_scanindex(qcoeff1, zero_mask1, iscan_ptr, off1), nonzero_scanindex(qcoeff2, zero_mask2, iscan_ptr, off2)); eob = vec_max(eob, eob2); // 24 int16_t is 48 bytes off0 += 48; off1 += 48; off2 += 48; num_itr--; } while (num_itr != 0); eob = vec_max_across(eob); *eob_ptr = eob[0]; }