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#ifndef _FRACMUL_H
#define _FRACMUL_H
/** FRACTIONAL MULTIPLICATION - TAKEN FROM apps/dsp.h
* Multiply two fixed point numbers with 31 fractional bits:
* FRACMUL(x, y)
*
* Multiply two fixed point numbers with 31 fractional bits,
* then shift left by z bits:
* FRACMUL_SHL(x, y, z)
* NOTE: z must be in the range 1-8 on Coldfire targets.
*/
/* A bunch of fixed point assembler helper macros */
#if defined(CPU_COLDFIRE)
/* These macros use the Coldfire EMAC extension and need the MACSR flags set
* to fractional mode with no rounding.
*/
/* Multiply two S.31 fractional integers and return the sign bit and the
* 31 most significant bits of the result.
*/
#define FRACMUL(x, y) \
({ \
long t; \
asm ("mac.l %[a], %[b], %%acc0\n\t" \
"movclr.l %%acc0, %[t]\n\t" \
: [t] "=r" (t) : [a] "r" (x), [b] "r" (y)); \
t; \
})
/* Multiply two S.31 fractional integers, and return the 32 most significant
* bits after a shift left by the constant z. NOTE: Only works for shifts of
* 1 to 8 on Coldfire!
*/
#define FRACMUL_SHL(x, y, z) \
({ \
long t, t2; \
asm ("mac.l %[a], %[b], %%acc0\n\t" \
"moveq.l %[d], %[t]\n\t" \
"move.l %%accext01, %[t2]\n\t" \
"and.l %[mask], %[t2]\n\t" \
"lsr.l %[t], %[t2]\n\t" \
"movclr.l %%acc0, %[t]\n\t" \
"asl.l %[c], %[t]\n\t" \
"or.l %[t2], %[t]\n\t" \
: [t] "=&d" (t), [t2] "=&d" (t2) \
: [a] "r" (x), [b] "r" (y), [mask] "d" (0xff), \
[c] "i" ((z)), [d] "i" (8 - (z))); \
t; \
})
#elif defined(CPU_ARM)
/* Multiply two S.31 fractional integers and return the sign bit and the
* 31 most significant bits of the result.
*/
#define FRACMUL(x, y) \
({ \
long t, t2; \
asm ("smull %[t], %[t2], %[a], %[b]\n\t" \
"mov %[t2], %[t2], asl #1\n\t" \
"orr %[t], %[t2], %[t], lsr #31\n\t" \
: [t] "=&r" (t), [t2] "=&r" (t2) \
: [a] "r" (x), [b] "r" (y)); \
t; \
})
/* Multiply two S.31 fractional integers, and return the 32 most significant
* bits after a shift left by the constant z.
*/
#define FRACMUL_SHL(x, y, z) \
({ \
long t, t2; \
asm ("smull %[t], %[t2], %[a], %[b]\n\t" \
"mov %[t2], %[t2], asl %[c]\n\t" \
"orr %[t], %[t2], %[t], lsr %[d]\n\t" \
: [t] "=&r" (t), [t2] "=&r" (t2) \
: [a] "r" (x), [b] "r" (y), \
[c] "M" ((z) + 1), [d] "M" (31 - (z))); \
t; \
})
#else
#define FRACMUL(x, y) (long) (((((long long) (x)) * ((long long) (y))) >> 31))
#define FRACMUL_SHL(x, y, z) \
((long)(((((long long) (x)) * ((long long) (y))) >> (31 - (z)))))
#endif
#endif
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