| 1 | /*************************************************************************** |
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| 2 | * Copyright (c) 2002-2009, Broadcom Corporation |
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| 3 | * All Rights Reserved |
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| 4 | * Confidential Property of Broadcom Corporation |
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| 5 | * |
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| 6 | * THIS SOFTWARE MAY ONLY BE USED SUBJECT TO AN EXECUTED SOFTWARE LICENSE |
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| 7 | * AGREEMENT BETWEEN THE USER AND BROADCOM. YOU HAVE NO RIGHT TO USE OR |
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| 8 | * EXPLOIT THIS MATERIAL EXCEPT SUBJECT TO THE TERMS OF SUCH AN AGREEMENT. |
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| 9 | * |
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| 10 | * Filename: mp2_smalldiv.c |
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| 11 | * |
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| 12 | ***************************************************************************/ |
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| 13 | |
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| 14 | #include "mp2.h" |
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| 15 | |
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| 16 | /* |
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| 17 | smalldiv returns 'q' and 'r' so |
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| 18 | |
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| 19 | q = (hi*RADIX + lo)/d; |
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| 20 | r = (hi*RADIX + lo)%d; |
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| 21 | |
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| 22 | Assumes 0 <= hi < d < RADIX and 0 <= lo < RADIX. |
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| 23 | */ |
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| 24 | int smalldiv (u32 hi, u32 lo, u32 d, u32 *q, u32 *r) |
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| 25 | { |
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| 26 | register u32 tmp; |
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| 27 | register u32 i; |
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| 28 | register u32 numbits = (NBITS << 1); |
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| 29 | |
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| 30 | register u32 lr = 0; |
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| 31 | register u32 lq = 0; |
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| 32 | |
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| 33 | if (d==0L) return 0; |
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| 34 | |
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| 35 | //printf("x= %d, hi = %x (%d), lo= %x (%d), d= %x (%d)\n", hi*RADIX+lo, hi, hi, lo, lo, d, d); |
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| 36 | if (hi) |
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| 37 | { |
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| 38 | while ( (tmp=((lr << 1) | ((hi & MSBMASK) >> NBITSM1))) < d ) |
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| 39 | { |
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| 40 | lr = tmp; |
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| 41 | hi = (hi << 1) & RADIXM;; |
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| 42 | lo <<= 1; |
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| 43 | if (lo>=RADIX) |
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| 44 | { |
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| 45 | hi |= 0x00000001L; |
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| 46 | lo &= RADIXM; |
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| 47 | } |
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| 48 | numbits--; |
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| 49 | //printf("x = %d, hi= %x (%d), lo= %x (%d), lr= %x (%d), numbits= %d\n", |
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| 50 | // hi*RADIX+lo, hi, hi, lo, lo, lr, lr, numbits); |
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| 51 | } |
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| 52 | for (i=0; i<numbits; i++) |
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| 53 | { |
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| 54 | lr = (lr << 1) | ((hi & MSBMASK) >> NBITSM1); |
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| 55 | lq = (lq << 1) & RADIXM; |
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| 56 | //printf("i= %d, lq = %x (%d), lr= %x (%d)\n", i, lq, lq, lr,lr); |
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| 57 | if (lr >= d) |
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| 58 | { |
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| 59 | //printf ("lr > d: lr= %x (%d), d= %d\n", lr, lr, d); |
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| 60 | lq |= 1; |
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| 61 | lr -= d; |
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| 62 | //printf ("lr > d: lq= %x (%d), lr= %x (%d)\n", lq, lq, lr, lr); |
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| 63 | } |
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| 64 | |
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| 65 | hi = (hi << 1) & RADIXM;; |
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| 66 | lo <<= 1; |
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| 67 | if (lo>=RADIX) |
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| 68 | { |
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| 69 | hi |= 0x00000001L; |
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| 70 | lo &= RADIXM; |
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| 71 | } |
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| 72 | //printf("x << 1: hi= %x (%d), lo= %x (%d)\n", hi, hi, lo, lo); |
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| 73 | } |
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| 74 | } |
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| 75 | else |
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| 76 | { |
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| 77 | lr = lo % d; |
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| 78 | lq = lo / d; |
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| 79 | } |
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| 80 | //printf("lq= %d, lr= %d\n", lq, lr); |
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| 81 | *r = lr; |
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| 82 | *q = lq; |
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| 83 | |
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| 84 | return 1; |
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| 85 | } |
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| 86 | |
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