jamulus/libs/celt/cc6_fixed_generic.h

/* Copyright (C) 2003-2008 Jean-Marc Valin, CSIRO */
/**
   @file fixed_generic.h
   @brief Generic fixed-point operations
*/
/*
   Redistribution and use in source and binary forms, with or without
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   are met:
   
   - Redistributions of source code must retain the above copyright
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   notice, this list of conditions and the following disclaimer in the
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   this software without specific prior written permission.
   
   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
   A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR
   CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
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   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

#ifndef cc6_FIXED_GENERIC_H
#define cc6_FIXED_GENERIC_H

/** Multiply a 16-bit signed value by a 16-bit unsigned value. The result is a 32-bit signed value */
#define cc6_MULT16_16SU(a,b) ((cc6_celt_word32_t)(cc6_celt_word16_t)(a)*(cc6_celt_word32_t)(cc6_celt_uint16_t)(b))

/** 16x32 multiplication, followed by a 16-bit shift right. Results fits in 32 bits */
#define cc6_MULT16_32_Q16(a,b) cc6_ADD32(cc6_MULT16_16((a),cc6_SHR((b),16)), cc6_SHR(cc6_MULT16_16SU((a),((b)&0x0000ffff)),16))

/** 16x32 multiplication, followed by a 15-bit shift right. Results fits in 32 bits */
#define cc6_MULT16_32_Q15(a,b) cc6_ADD32(cc6_SHL(cc6_MULT16_16((a),cc6_SHR((b),16)),1), cc6_SHR(cc6_MULT16_16SU((a),((b)&0x0000ffff)),15))

/** 32x32 multiplication, followed by a 31-bit shift right. Results fits in 32 bits */
#define cc6_MULT32_32_Q31(a,b) cc6_ADD32(cc6_ADD32(cc6_SHL(cc6_MULT16_16(cc6_SHR((a),16),cc6_SHR((b),16)),1), cc6_SHR(cc6_MULT16_16SU(cc6_SHR((a),16),((b)&0x0000ffff)),15)), cc6_SHR(cc6_MULT16_16SU(cc6_SHR((b),16),((a)&0x0000ffff)),15))

/** 32x32 multiplication, followed by a 32-bit shift right. Results fits in 32 bits */
#define cc6_MULT32_32_Q32(a,b) cc6_ADD32(cc6_ADD32(cc6_MULT16_16(cc6_SHR((a),16),cc6_SHR((b),16)), cc6_SHR(cc6_MULT16_16SU(cc6_SHR((a),16),((b)&0x0000ffff)),16)), cc6_SHR(cc6_MULT16_16SU(cc6_SHR((b),16),((a)&0x0000ffff)),16))

/** Compile-time conversion of float constant to 16-bit value */
#define cc6_QCONST16(x,bits) ((cc6_celt_word16_t)(.5+(x)*(((cc6_celt_word32_t)1)<<(bits))))
/** Compile-time conversion of float constant to 32-bit value */
#define cc6_QCONST32(x,bits) ((cc6_celt_word32_t)(.5+(x)*(((cc6_celt_word32_t)1)<<(bits))))

/** Negate a 16-bit value */
#define cc6_NEG16(x) (-(x))
/** Negate a 32-bit value */
#define cc6_NEG32(x) (-(x))

/** Change a 32-bit value into a 16-bit value. The value is assumed to fit in 16-bit, otherwise the result is undefined */
#define cc6_EXTRACT16(x) ((cc6_celt_word16_t)(x))
/** Change a 16-bit value into a 32-bit value */
#define cc6_EXTEND32(x) ((cc6_celt_word32_t)(x))

/** Arithmetic shift-right of a 16-bit value */
#define cc6_SHR16(a,shift) ((a) >> (shift))
/** Arithmetic shift-left of a 16-bit value */
#define cc6_SHL16(a,shift) ((a) << (shift))
/** Arithmetic shift-right of a 32-bit value */
#define cc6_SHR32(a,shift) ((a) >> (shift))
/** Arithmetic shift-left of a 32-bit value */
#define cc6_SHL32(a,shift) ((cc6_celt_word32_t)(a) << (shift))

/** 16-bit arithmetic shift right with rounding-to-nearest instead of rounding down */
#define cc6_PSHR16(a,shift) (cc6_SHR16((a)+((1<<((shift))>>1)),shift))
/** 32-bit arithmetic shift right with rounding-to-nearest instead of rounding down */
#define cc6_PSHR32(a,shift) (cc6_SHR32((a)+((cc6_EXTEND32(1)<<((shift))>>1)),shift))
/** 32-bit arithmetic shift right where the argument can be negative */
#define cc6_VSHR32(a, shift) (((shift)>0) ? cc6_SHR32(a, shift) : cc6_SHL32(a, -(shift)))

/** Saturates 16-bit value to +/- a */
#define cc6_SATURATE16(x,a) (((x)>(a) ? (a) : (x)<-(a) ? -(a) : (x)))
/** Saturates 32-bit value to +/- a */
#define cc6_SATURATE32(x,a) (((x)>(a) ? (a) : (x)<-(a) ? -(a) : (x)))

/** "RAW" macros, should not be used outside of this header file */
#define cc6_SHR(a,shift) ((a) >> (shift))
#define cc6_SHL(a,shift) ((cc6_celt_word32_t)(a) << (shift))
#define cc6_PSHR(a,shift) (cc6_SHR((a)+((cc6_EXTEND32(1)<<((shift))>>1)),shift))
#define cc6_SATURATE(x,a) (((x)>(a) ? (a) : (x)<-(a) ? -(a) : (x)))

/** Shift by a and round-to-neareast 32-bit value. Result is a 16-bit value */
#define cc6_ROUND16(x,a) (cc6_EXTRACT16(cc6_PSHR32((x),(a))))
/** Divide by two */
#define cc6_HALF32(x)  (cc6_SHR32(x,1))

/** Add two 16-bit values */
#define cc6_ADD16(a,b) ((cc6_celt_word16_t)((cc6_celt_word16_t)(a)+(cc6_celt_word16_t)(b)))
/** Subtract two 16-bit values */
#define cc6_SUB16(a,b) ((cc6_celt_word16_t)(a)-(cc6_celt_word16_t)(b))
/** Add two 32-bit values */
#define cc6_ADD32(a,b) ((cc6_celt_word32_t)(a)+(cc6_celt_word32_t)(b))
/** Subtract two 32-bit values */
#define cc6_SUB32(a,b) ((cc6_celt_word32_t)(a)-(cc6_celt_word32_t)(b))


/** 16x16 multiplication where the result fits in 16 bits */
#define cc6_MULT16_16_16(a,b)     ((((cc6_celt_word16_t)(a))*((cc6_celt_word16_t)(b))))

/* (cc6_celt_word32_t)(cc6_celt_word16_t) gives TI compiler a hint that it's 16x16->32 multiply */
/** 16x16 multiplication where the result fits in 32 bits */
#define cc6_MULT16_16(a,b)     (((cc6_celt_word32_t)(cc6_celt_word16_t)(a))*((cc6_celt_word32_t)(cc6_celt_word16_t)(b)))

/** 16x16 multiply-add where the result fits in 32 bits */
#define cc6_MAC16_16(c,a,b) (cc6_ADD32((c),cc6_MULT16_16((a),(b))))
/** 16x32 multiplication, followed by a 12-bit shift right. Results fits in 32 bits */
#define cc6_MULT16_32_Q12(a,b) cc6_ADD32(cc6_MULT16_16((a),cc6_SHR((b),12)), cc6_SHR(cc6_MULT16_16((a),((b)&0x00000fff)),12))
/** 16x32 multiplication, followed by a 13-bit shift right. Results fits in 32 bits */
#define cc6_MULT16_32_Q13(a,b) cc6_ADD32(cc6_MULT16_16((a),cc6_SHR((b),13)), cc6_SHR(cc6_MULT16_16((a),((b)&0x00001fff)),13))
/** 16x32 multiplication, followed by a 14-bit shift right. Results fits in 32 bits */
#define cc6_MULT16_32_Q14(a,b) cc6_ADD32(cc6_MULT16_16((a),cc6_SHR((b),14)), cc6_SHR(cc6_MULT16_16((a),((b)&0x00003fff)),14))

/** 16x32 multiplication, followed by an 11-bit shift right. Results fits in 32 bits */
#define cc6_MULT16_32_Q11(a,b) cc6_ADD32(cc6_MULT16_16((a),cc6_SHR((b),11)), cc6_SHR(cc6_MULT16_16((a),((b)&0x000007ff)),11))
/** 16x32 multiply-add, followed by an 11-bit shift right. Results fits in 32 bits */
#define cc6_MAC16_32_Q11(c,a,b) cc6_ADD32(c,cc6_ADD32(cc6_MULT16_16((a),cc6_SHR((b),11)), cc6_SHR(cc6_MULT16_16((a),((b)&0x000007ff)),11)))

/** 16x32 multiplication, followed by a 15-bit shift right (round-to-nearest). Results fits in 32 bits */
#define cc6_MULT16_32_P15(a,b) cc6_ADD32(cc6_MULT16_16((a),cc6_SHR((b),15)), cc6_PSHR(cc6_MULT16_16((a),((b)&0x00007fff)),15))
/** 16x32 multiply-add, followed by a 15-bit shift right. Results fits in 32 bits */
#define cc6_MAC16_32_Q15(c,a,b) cc6_ADD32(c,cc6_ADD32(cc6_MULT16_16((a),cc6_SHR((b),15)), cc6_SHR(cc6_MULT16_16((a),((b)&0x00007fff)),15)))


#define cc6_MAC16_16_Q11(c,a,b)     (cc6_ADD32((c),cc6_SHR(cc6_MULT16_16((a),(b)),11)))
#define cc6_MAC16_16_Q13(c,a,b)     (cc6_ADD32((c),cc6_SHR(cc6_MULT16_16((a),(b)),13)))
#define cc6_MAC16_16_P13(c,a,b)     (cc6_ADD32((c),cc6_SHR(cc6_ADD32(4096,cc6_MULT16_16((a),(b))),13)))

#define cc6_MULT16_16_Q11_32(a,b) (cc6_SHR(cc6_MULT16_16((a),(b)),11))
#define cc6_MULT16_16_Q13(a,b) (cc6_SHR(cc6_MULT16_16((a),(b)),13))
#define cc6_MULT16_16_Q14(a,b) (cc6_SHR(cc6_MULT16_16((a),(b)),14))
#define cc6_MULT16_16_Q15(a,b) (cc6_SHR(cc6_MULT16_16((a),(b)),15))

#define cc6_MULT16_16_P13(a,b) (cc6_SHR(cc6_ADD32(4096,cc6_MULT16_16((a),(b))),13))
#define cc6_MULT16_16_P14(a,b) (cc6_SHR(cc6_ADD32(8192,cc6_MULT16_16((a),(b))),14))
#define cc6_MULT16_16_P15(a,b) (cc6_SHR(cc6_ADD32(16384,cc6_MULT16_16((a),(b))),15))

/** Divide a 32-bit value by a 16-bit value. Result fits in 16 bits */
#define cc6_DIV32_16(a,b) ((cc6_celt_word16_t)(((cc6_celt_word32_t)(a))/((cc6_celt_word16_t)(b))))
/** Divide a 32-bit value by a 16-bit value and round to nearest. Result fits in 16 bits */
#define cc6_PDIV32_16(a,b) ((cc6_celt_word16_t)(((cc6_celt_word32_t)(a)+((cc6_celt_word16_t)(b)>>1))/((cc6_celt_word16_t)(b))))
/** Divide a 32-bit value by a 32-bit value. Result fits in 32 bits */
#define cc6_DIV32(a,b) (((cc6_celt_word32_t)(a))/((cc6_celt_word32_t)(b)))
/** Divide a 32-bit value by a 32-bit value and round to nearest. Result fits in 32 bits */
#define cc6_PDIV32(a,b) (((cc6_celt_word32_t)(a)+((cc6_celt_word16_t)(b)>>1))/((cc6_celt_word32_t)(b)))

#endif