Chris@69: /* Copyright (C) 2007-2009 Xiph.Org Foundation
Chris@69:    Copyright (C) 2003-2008 Jean-Marc Valin
Chris@69:    Copyright (C) 2007-2008 CSIRO */
Chris@69: /**
Chris@69:    @file fixed_generic.h
Chris@69:    @brief Generic fixed-point operations
Chris@69: */
Chris@69: /*
Chris@69:    Redistribution and use in source and binary forms, with or without
Chris@69:    modification, are permitted provided that the following conditions
Chris@69:    are met:
Chris@69: 
Chris@69:    - Redistributions of source code must retain the above copyright
Chris@69:    notice, this list of conditions and the following disclaimer.
Chris@69: 
Chris@69:    - Redistributions in binary form must reproduce the above copyright
Chris@69:    notice, this list of conditions and the following disclaimer in the
Chris@69:    documentation and/or other materials provided with the distribution.
Chris@69: 
Chris@69:    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
Chris@69:    ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
Chris@69:    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
Chris@69:    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
Chris@69:    OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
Chris@69:    EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
Chris@69:    PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
Chris@69:    PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
Chris@69:    LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
Chris@69:    NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
Chris@69:    SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
Chris@69: */
Chris@69: 
Chris@69: #ifndef FIXED_GENERIC_H
Chris@69: #define FIXED_GENERIC_H
Chris@69: 
Chris@69: /** Multiply a 16-bit signed value by a 16-bit unsigned value. The result is a 32-bit signed value */
Chris@69: #define MULT16_16SU(a,b) ((opus_val32)(opus_val16)(a)*(opus_val32)(opus_uint16)(b))
Chris@69: 
Chris@69: /** 16x32 multiplication, followed by a 16-bit shift right. Results fits in 32 bits */
Chris@69: #if OPUS_FAST_INT64
Chris@69: #define MULT16_32_Q16(a,b) ((opus_val32)SHR((opus_int64)((opus_val16)(a))*(b),16))
Chris@69: #else
Chris@69: #define MULT16_32_Q16(a,b) ADD32(MULT16_16((a),SHR((b),16)), SHR(MULT16_16SU((a),((b)&0x0000ffff)),16))
Chris@69: #endif
Chris@69: 
Chris@69: /** 16x32 multiplication, followed by a 16-bit shift right (round-to-nearest). Results fits in 32 bits */
Chris@69: #if OPUS_FAST_INT64
Chris@69: #define MULT16_32_P16(a,b) ((opus_val32)PSHR((opus_int64)((opus_val16)(a))*(b),16))
Chris@69: #else
Chris@69: #define MULT16_32_P16(a,b) ADD32(MULT16_16((a),SHR((b),16)), PSHR(MULT16_16SU((a),((b)&0x0000ffff)),16))
Chris@69: #endif
Chris@69: 
Chris@69: /** 16x32 multiplication, followed by a 15-bit shift right. Results fits in 32 bits */
Chris@69: #if OPUS_FAST_INT64
Chris@69: #define MULT16_32_Q15(a,b) ((opus_val32)SHR((opus_int64)((opus_val16)(a))*(b),15))
Chris@69: #else
Chris@69: #define MULT16_32_Q15(a,b) ADD32(SHL(MULT16_16((a),SHR((b),16)),1), SHR(MULT16_16SU((a),((b)&0x0000ffff)),15))
Chris@69: #endif
Chris@69: 
Chris@69: /** 32x32 multiplication, followed by a 31-bit shift right. Results fits in 32 bits */
Chris@69: #if OPUS_FAST_INT64
Chris@69: #define MULT32_32_Q31(a,b) ((opus_val32)SHR((opus_int64)(a)*(opus_int64)(b),31))
Chris@69: #else
Chris@69: #define MULT32_32_Q31(a,b) ADD32(ADD32(SHL(MULT16_16(SHR((a),16),SHR((b),16)),1), SHR(MULT16_16SU(SHR((a),16),((b)&0x0000ffff)),15)), SHR(MULT16_16SU(SHR((b),16),((a)&0x0000ffff)),15))
Chris@69: #endif
Chris@69: 
Chris@69: /** Compile-time conversion of float constant to 16-bit value */
Chris@69: #define QCONST16(x,bits) ((opus_val16)(.5+(x)*(((opus_val32)1)<<(bits))))
Chris@69: 
Chris@69: /** Compile-time conversion of float constant to 32-bit value */
Chris@69: #define QCONST32(x,bits) ((opus_val32)(.5+(x)*(((opus_val32)1)<<(bits))))
Chris@69: 
Chris@69: /** Negate a 16-bit value */
Chris@69: #define NEG16(x) (-(x))
Chris@69: /** Negate a 32-bit value */
Chris@69: #define NEG32(x) (-(x))
Chris@69: 
Chris@69: /** Change a 32-bit value into a 16-bit value. The value is assumed to fit in 16-bit, otherwise the result is undefined */
Chris@69: #define EXTRACT16(x) ((opus_val16)(x))
Chris@69: /** Change a 16-bit value into a 32-bit value */
Chris@69: #define EXTEND32(x) ((opus_val32)(x))
Chris@69: 
Chris@69: /** Arithmetic shift-right of a 16-bit value */
Chris@69: #define SHR16(a,shift) ((a) >> (shift))
Chris@69: /** Arithmetic shift-left of a 16-bit value */
Chris@69: #define SHL16(a,shift) ((opus_int16)((opus_uint16)(a)<<(shift)))
Chris@69: /** Arithmetic shift-right of a 32-bit value */
Chris@69: #define SHR32(a,shift) ((a) >> (shift))
Chris@69: /** Arithmetic shift-left of a 32-bit value */
Chris@69: #define SHL32(a,shift) ((opus_int32)((opus_uint32)(a)<<(shift)))
Chris@69: 
Chris@69: /** 32-bit arithmetic shift right with rounding-to-nearest instead of rounding down */
Chris@69: #define PSHR32(a,shift) (SHR32((a)+((EXTEND32(1)<<((shift))>>1)),shift))
Chris@69: /** 32-bit arithmetic shift right where the argument can be negative */
Chris@69: #define VSHR32(a, shift) (((shift)>0) ? SHR32(a, shift) : SHL32(a, -(shift)))
Chris@69: 
Chris@69: /** "RAW" macros, should not be used outside of this header file */
Chris@69: #define SHR(a,shift) ((a) >> (shift))
Chris@69: #define SHL(a,shift) SHL32(a,shift)
Chris@69: #define PSHR(a,shift) (SHR((a)+((EXTEND32(1)<<((shift))>>1)),shift))
Chris@69: #define SATURATE(x,a) (((x)>(a) ? (a) : (x)<-(a) ? -(a) : (x)))
Chris@69: 
Chris@69: #define SATURATE16(x) (EXTRACT16((x)>32767 ? 32767 : (x)<-32768 ? -32768 : (x)))
Chris@69: 
Chris@69: /** Shift by a and round-to-neareast 32-bit value. Result is a 16-bit value */
Chris@69: #define ROUND16(x,a) (EXTRACT16(PSHR32((x),(a))))
Chris@69: /** Shift by a and round-to-neareast 32-bit value. Result is a saturated 16-bit value */
Chris@69: #define SROUND16(x,a) EXTRACT16(SATURATE(PSHR32(x,a), 32767));
Chris@69: 
Chris@69: /** Divide by two */
Chris@69: #define HALF16(x)  (SHR16(x,1))
Chris@69: #define HALF32(x)  (SHR32(x,1))
Chris@69: 
Chris@69: /** Add two 16-bit values */
Chris@69: #define ADD16(a,b) ((opus_val16)((opus_val16)(a)+(opus_val16)(b)))
Chris@69: /** Subtract two 16-bit values */
Chris@69: #define SUB16(a,b) ((opus_val16)(a)-(opus_val16)(b))
Chris@69: /** Add two 32-bit values */
Chris@69: #define ADD32(a,b) ((opus_val32)(a)+(opus_val32)(b))
Chris@69: /** Subtract two 32-bit values */
Chris@69: #define SUB32(a,b) ((opus_val32)(a)-(opus_val32)(b))
Chris@69: 
Chris@69: /** Add two 32-bit values, ignore any overflows */
Chris@69: #define ADD32_ovflw(a,b) ((opus_val32)((opus_uint32)(a)+(opus_uint32)(b)))
Chris@69: /** Subtract two 32-bit values, ignore any overflows */
Chris@69: #define SUB32_ovflw(a,b) ((opus_val32)((opus_uint32)(a)-(opus_uint32)(b)))
Chris@69: /* Avoid MSVC warning C4146: unary minus operator applied to unsigned type */
Chris@69: /** Negate 32-bit value, ignore any overflows */
Chris@69: #define NEG32_ovflw(a) ((opus_val32)(0-(opus_uint32)(a)))
Chris@69: 
Chris@69: /** 16x16 multiplication where the result fits in 16 bits */
Chris@69: #define MULT16_16_16(a,b)     ((((opus_val16)(a))*((opus_val16)(b))))
Chris@69: 
Chris@69: /* (opus_val32)(opus_val16) gives TI compiler a hint that it's 16x16->32 multiply */
Chris@69: /** 16x16 multiplication where the result fits in 32 bits */
Chris@69: #define MULT16_16(a,b)     (((opus_val32)(opus_val16)(a))*((opus_val32)(opus_val16)(b)))
Chris@69: 
Chris@69: /** 16x16 multiply-add where the result fits in 32 bits */
Chris@69: #define MAC16_16(c,a,b) (ADD32((c),MULT16_16((a),(b))))
Chris@69: /** 16x32 multiply, followed by a 15-bit shift right and 32-bit add.
Chris@69:     b must fit in 31 bits.
Chris@69:     Result fits in 32 bits. */
Chris@69: #define MAC16_32_Q15(c,a,b) ADD32((c),ADD32(MULT16_16((a),SHR((b),15)), SHR(MULT16_16((a),((b)&0x00007fff)),15)))
Chris@69: 
Chris@69: /** 16x32 multiplication, followed by a 16-bit shift right and 32-bit add.
Chris@69:     Results fits in 32 bits */
Chris@69: #define MAC16_32_Q16(c,a,b) ADD32((c),ADD32(MULT16_16((a),SHR((b),16)), SHR(MULT16_16SU((a),((b)&0x0000ffff)),16)))
Chris@69: 
Chris@69: #define MULT16_16_Q11_32(a,b) (SHR(MULT16_16((a),(b)),11))
Chris@69: #define MULT16_16_Q11(a,b) (SHR(MULT16_16((a),(b)),11))
Chris@69: #define MULT16_16_Q13(a,b) (SHR(MULT16_16((a),(b)),13))
Chris@69: #define MULT16_16_Q14(a,b) (SHR(MULT16_16((a),(b)),14))
Chris@69: #define MULT16_16_Q15(a,b) (SHR(MULT16_16((a),(b)),15))
Chris@69: 
Chris@69: #define MULT16_16_P13(a,b) (SHR(ADD32(4096,MULT16_16((a),(b))),13))
Chris@69: #define MULT16_16_P14(a,b) (SHR(ADD32(8192,MULT16_16((a),(b))),14))
Chris@69: #define MULT16_16_P15(a,b) (SHR(ADD32(16384,MULT16_16((a),(b))),15))
Chris@69: 
Chris@69: /** Divide a 32-bit value by a 16-bit value. Result fits in 16 bits */
Chris@69: #define DIV32_16(a,b) ((opus_val16)(((opus_val32)(a))/((opus_val16)(b))))
Chris@69: 
Chris@69: /** Divide a 32-bit value by a 32-bit value. Result fits in 32 bits */
Chris@69: #define DIV32(a,b) (((opus_val32)(a))/((opus_val32)(b)))
Chris@69: 
Chris@69: #if defined(MIPSr1_ASM)
Chris@69: #include "mips/fixed_generic_mipsr1.h"
Chris@69: #endif
Chris@69: 
Chris@69: static OPUS_INLINE opus_val16 SIG2WORD16_generic(celt_sig x)
Chris@69: {
Chris@69:    x = PSHR32(x, SIG_SHIFT);
Chris@69:    x = MAX32(x, -32768);
Chris@69:    x = MIN32(x, 32767);
Chris@69:    return EXTRACT16(x);
Chris@69: }
Chris@69: #define SIG2WORD16(x) (SIG2WORD16_generic(x))
Chris@69: 
Chris@69: #endif