fixed_generic.h

00001 /* Copyright (C) 2003 Jean-Marc Valin */
00002 /**
00003    @file fixed_generic.h
00004    @brief Generic fixed-point operations
00005 */
00006 /*
00007    Redistribution and use in source and binary forms, with or without
00008    modification, are permitted provided that the following conditions
00009    are met:
00010    
00011    - Redistributions of source code must retain the above copyright
00012    notice, this list of conditions and the following disclaimer.
00013    
00014    - Redistributions in binary form must reproduce the above copyright
00015    notice, this list of conditions and the following disclaimer in the
00016    documentation and/or other materials provided with the distribution.
00017    
00018    - Neither the name of the Xiph.org Foundation nor the names of its
00019    contributors may be used to endorse or promote products derived from
00020    this software without specific prior written permission.
00021    
00022    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
00023    ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
00024    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
00025    A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR
00026    CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
00027    EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
00028    PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
00029    PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
00030    LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
00031    NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
00032    SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
00033 */
00034 
00035 #ifndef FIXED_GENERIC_H
00036 #define FIXED_GENERIC_H
00037 
00038 #define QCONST16(x,bits) ((spx_word16_t)(.5+(x)*(((spx_word32_t)1)<<(bits))))
00039 #define QCONST32(x,bits) ((spx_word32_t)(.5+(x)*(((spx_word32_t)1)<<(bits))))
00040 
00041 #define NEG16(x) (-(x))
00042 #define NEG32(x) (-(x))
00043 #define EXTRACT16(x) ((spx_word16_t)(x))
00044 #define EXTEND32(x) ((spx_word32_t)(x))
00045 #define SHR16(a,shift) ((a) >> (shift))
00046 #define SHL16(a,shift) ((a) << (shift))
00047 #define SHR32(a,shift) ((a) >> (shift))
00048 #define SHL32(a,shift) ((a) << (shift))
00049 #define PSHR16(a,shift) (SHR16((a)+((1<<((shift))>>1)),shift))
00050 #define PSHR32(a,shift) (SHR32((a)+((1<<((shift))>>1)),shift))
00051 #define VSHR32(a, shift) (((shift)>0) ? SHR32(a, shift) : SHL32(a, -(shift)))
00052 #define SATURATE16(x,a) (((x)>(a) ? (a) : (x)<-(a) ? -(a) : (x)))
00053 #define SATURATE32(x,a) (((x)>(a) ? (a) : (x)<-(a) ? -(a) : (x)))
00054 
00055 #define SHR(a,shift) ((a) >> (shift))
00056 #define SHL(a,shift) ((spx_word32_t)(a) << (shift))
00057 #define PSHR(a,shift) (SHR((a)+((1<<((shift))>>1)),shift))
00058 #define SATURATE(x,a) (((x)>(a) ? (a) : (x)<-(a) ? -(a) : (x)))
00059 
00060 
00061 #define ADD16(a,b) ((spx_word16_t)((spx_word16_t)(a)+(spx_word16_t)(b)))
00062 #define SUB16(a,b) ((spx_word16_t)(a)-(spx_word16_t)(b))
00063 #define ADD32(a,b) ((spx_word32_t)(a)+(spx_word32_t)(b))
00064 #define SUB32(a,b) ((spx_word32_t)(a)-(spx_word32_t)(b))
00065 
00066 
00067 /* result fits in 16 bits */
00068 #define MULT16_16_16(a,b)     ((((spx_word16_t)(a))*((spx_word16_t)(b))))
00069 
00070 /* (spx_word32_t)(spx_word16_t) gives TI compiler a hint that it's 16x16->32 multiply */
00071 #define MULT16_16(a,b)     (((spx_word32_t)(spx_word16_t)(a))*((spx_word32_t)(spx_word16_t)(b)))
00072 
00073 #define MAC16_16(c,a,b) (ADD32((c),MULT16_16((a),(b))))
00074 #define MULT16_32_Q12(a,b) ADD32(MULT16_16((a),SHR((b),12)), SHR(MULT16_16((a),((b)&0x00000fff)),12))
00075 #define MULT16_32_Q13(a,b) ADD32(MULT16_16((a),SHR((b),13)), SHR(MULT16_16((a),((b)&0x00001fff)),13))
00076 #define MULT16_32_Q14(a,b) ADD32(MULT16_16((a),SHR((b),14)), SHR(MULT16_16((a),((b)&0x00003fff)),14))
00077 
00078 #define MULT16_32_Q11(a,b) ADD32(MULT16_16((a),SHR((b),11)), SHR(MULT16_16((a),((b)&0x000007ff)),11))
00079 #define MAC16_32_Q11(c,a,b) ADD32(c,ADD32(MULT16_16((a),SHR((b),11)), SHR(MULT16_16((a),((b)&0x000007ff)),11)))
00080 
00081 #define MULT16_32_P15(a,b) ADD32(MULT16_16((a),SHR((b),15)), PSHR(MULT16_16((a),((b)&0x00007fff)),15))
00082 #define MULT16_32_Q15(a,b) ADD32(MULT16_16((a),SHR((b),15)), SHR(MULT16_16((a),((b)&0x00007fff)),15))
00083 #define MAC16_32_Q15(c,a,b) ADD32(c,ADD32(MULT16_16((a),SHR((b),15)), SHR(MULT16_16((a),((b)&0x00007fff)),15)))
00084 
00085 
00086 #define MAC16_16_Q11(c,a,b)     (ADD32((c),SHR(MULT16_16((a),(b)),11)))
00087 #define MAC16_16_Q13(c,a,b)     (ADD32((c),SHR(MULT16_16((a),(b)),13)))
00088 #define MAC16_16_P13(c,a,b)     (ADD32((c),SHR(ADD32(4096,MULT16_16((a),(b))),13)))
00089 
00090 #define MULT16_16_Q11_32(a,b) (SHR(MULT16_16((a),(b)),11))
00091 #define MULT16_16_Q13(a,b) (SHR(MULT16_16((a),(b)),13))
00092 #define MULT16_16_Q14(a,b) (SHR(MULT16_16((a),(b)),14))
00093 #define MULT16_16_Q15(a,b) (SHR(MULT16_16((a),(b)),15))
00094 
00095 #define MULT16_16_P13(a,b) (SHR(ADD32(4096,MULT16_16((a),(b))),13))
00096 #define MULT16_16_P14(a,b) (SHR(ADD32(8192,MULT16_16((a),(b))),14))
00097 #define MULT16_16_P15(a,b) (SHR(ADD32(16384,MULT16_16((a),(b))),15))
00098 
00099 #define MUL_16_32_R15(a,bh,bl) ADD32(MULT16_16((a),(bh)), SHR(MULT16_16((a),(bl)),15))
00100 
00101 #define DIV32_16(a,b) ((spx_word16_t)(((spx_word32_t)(a))/((spx_word16_t)(b))))
00102 #define PDIV32_16(a,b) ((spx_word16_t)(((spx_word32_t)(a)+((spx_word16_t)(b)>>1))/((spx_word16_t)(b))))
00103 #define DIV32(a,b) (((spx_word32_t)(a))/((spx_word32_t)(b)))
00104 #define PDIV32(a,b) (((spx_word32_t)(a)+((spx_word16_t)(b)>>1))/((spx_word32_t)(b)))
00105 
00106 #endif