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authorGeert Uytterhoeven <geert@linux-m68k.org>2011-06-12 11:01:21 +0200
committerGeert Uytterhoeven <geert@linux-m68k.org>2011-07-30 21:21:40 +0200
commitffe6c42aa3f731f8707e49c39b4b37310ed363e9 (patch)
tree5feac6358f9bddf949122074f939f3106de24b5f
parentb2cb92417d301f46801695243df5061a9bd31dd5 (diff)
m68k/math-emu: Remove commented out old code
It's been unused for ages, and contains bugs (e.g. incorrect shifts in lsl64()). Reported-by: Jonathan Elchison <jelchison@gmail.com> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
-rw-r--r--arch/m68k/math-emu/multi_arith.h530
1 files changed, 0 insertions, 530 deletions
diff --git a/arch/m68k/math-emu/multi_arith.h b/arch/m68k/math-emu/multi_arith.h
index 4ad0ca918e2e..4b5eb3d85638 100644
--- a/arch/m68k/math-emu/multi_arith.h
+++ b/arch/m68k/math-emu/multi_arith.h
@@ -19,246 +19,6 @@
#ifndef MULTI_ARITH_H
#define MULTI_ARITH_H
-#if 0 /* old code... */
-
-/* Unsigned only, because we don't need signs to multiply and divide. */
-typedef unsigned int int128[4];
-
-/* Word order */
-enum {
- MSW128,
- NMSW128,
- NLSW128,
- LSW128
-};
-
-/* big-endian */
-#define LO_WORD(ll) (((unsigned int *) &ll)[1])
-#define HI_WORD(ll) (((unsigned int *) &ll)[0])
-
-/* Convenience functions to stuff various integer values into int128s */
-
-static inline void zero128(int128 a)
-{
- a[LSW128] = a[NLSW128] = a[NMSW128] = a[MSW128] = 0;
-}
-
-/* Human-readable word order in the arguments */
-static inline void set128(unsigned int i3, unsigned int i2, unsigned int i1,
- unsigned int i0, int128 a)
-{
- a[LSW128] = i0;
- a[NLSW128] = i1;
- a[NMSW128] = i2;
- a[MSW128] = i3;
-}
-
-/* Convenience functions (for testing as well) */
-static inline void int64_to_128(unsigned long long src, int128 dest)
-{
- dest[LSW128] = (unsigned int) src;
- dest[NLSW128] = src >> 32;
- dest[NMSW128] = dest[MSW128] = 0;
-}
-
-static inline void int128_to_64(const int128 src, unsigned long long *dest)
-{
- *dest = src[LSW128] | (long long) src[NLSW128] << 32;
-}
-
-static inline void put_i128(const int128 a)
-{
- printk("%08x %08x %08x %08x\n", a[MSW128], a[NMSW128],
- a[NLSW128], a[LSW128]);
-}
-
-/* Internal shifters:
-
- Note that these are only good for 0 < count < 32.
- */
-
-static inline void _lsl128(unsigned int count, int128 a)
-{
- a[MSW128] = (a[MSW128] << count) | (a[NMSW128] >> (32 - count));
- a[NMSW128] = (a[NMSW128] << count) | (a[NLSW128] >> (32 - count));
- a[NLSW128] = (a[NLSW128] << count) | (a[LSW128] >> (32 - count));
- a[LSW128] <<= count;
-}
-
-static inline void _lsr128(unsigned int count, int128 a)
-{
- a[LSW128] = (a[LSW128] >> count) | (a[NLSW128] << (32 - count));
- a[NLSW128] = (a[NLSW128] >> count) | (a[NMSW128] << (32 - count));
- a[NMSW128] = (a[NMSW128] >> count) | (a[MSW128] << (32 - count));
- a[MSW128] >>= count;
-}
-
-/* Should be faster, one would hope */
-
-static inline void lslone128(int128 a)
-{
- asm volatile ("lsl.l #1,%0\n"
- "roxl.l #1,%1\n"
- "roxl.l #1,%2\n"
- "roxl.l #1,%3\n"
- :
- "=d" (a[LSW128]),
- "=d"(a[NLSW128]),
- "=d"(a[NMSW128]),
- "=d"(a[MSW128])
- :
- "0"(a[LSW128]),
- "1"(a[NLSW128]),
- "2"(a[NMSW128]),
- "3"(a[MSW128]));
-}
-
-static inline void lsrone128(int128 a)
-{
- asm volatile ("lsr.l #1,%0\n"
- "roxr.l #1,%1\n"
- "roxr.l #1,%2\n"
- "roxr.l #1,%3\n"
- :
- "=d" (a[MSW128]),
- "=d"(a[NMSW128]),
- "=d"(a[NLSW128]),
- "=d"(a[LSW128])
- :
- "0"(a[MSW128]),
- "1"(a[NMSW128]),
- "2"(a[NLSW128]),
- "3"(a[LSW128]));
-}
-
-/* Generalized 128-bit shifters:
-
- These bit-shift to a multiple of 32, then move whole longwords. */
-
-static inline void lsl128(unsigned int count, int128 a)
-{
- int wordcount, i;
-
- if (count % 32)
- _lsl128(count % 32, a);
-
- if (0 == (wordcount = count / 32))
- return;
-
- /* argh, gak, endian-sensitive */
- for (i = 0; i < 4 - wordcount; i++) {
- a[i] = a[i + wordcount];
- }
- for (i = 3; i >= 4 - wordcount; --i) {
- a[i] = 0;
- }
-}
-
-static inline void lsr128(unsigned int count, int128 a)
-{
- int wordcount, i;
-
- if (count % 32)
- _lsr128(count % 32, a);
-
- if (0 == (wordcount = count / 32))
- return;
-
- for (i = 3; i >= wordcount; --i) {
- a[i] = a[i - wordcount];
- }
- for (i = 0; i < wordcount; i++) {
- a[i] = 0;
- }
-}
-
-static inline int orl128(int a, int128 b)
-{
- b[LSW128] |= a;
-}
-
-static inline int btsthi128(const int128 a)
-{
- return a[MSW128] & 0x80000000;
-}
-
-/* test bits (numbered from 0 = LSB) up to and including "top" */
-static inline int bftestlo128(int top, const int128 a)
-{
- int r = 0;
-
- if (top > 31)
- r |= a[LSW128];
- if (top > 63)
- r |= a[NLSW128];
- if (top > 95)
- r |= a[NMSW128];
-
- r |= a[3 - (top / 32)] & ((1 << (top % 32 + 1)) - 1);
-
- return (r != 0);
-}
-
-/* Aargh. We need these because GCC is broken */
-/* FIXME: do them in assembly, for goodness' sake! */
-static inline void mask64(int pos, unsigned long long *mask)
-{
- *mask = 0;
-
- if (pos < 32) {
- LO_WORD(*mask) = (1 << pos) - 1;
- return;
- }
- LO_WORD(*mask) = -1;
- HI_WORD(*mask) = (1 << (pos - 32)) - 1;
-}
-
-static inline void bset64(int pos, unsigned long long *dest)
-{
- /* This conditional will be optimized away. Thanks, GCC! */
- if (pos < 32)
- asm volatile ("bset %1,%0":"=m"
- (LO_WORD(*dest)):"id"(pos));
- else
- asm volatile ("bset %1,%0":"=m"
- (HI_WORD(*dest)):"id"(pos - 32));
-}
-
-static inline int btst64(int pos, unsigned long long dest)
-{
- if (pos < 32)
- return (0 != (LO_WORD(dest) & (1 << pos)));
- else
- return (0 != (HI_WORD(dest) & (1 << (pos - 32))));
-}
-
-static inline void lsl64(int count, unsigned long long *dest)
-{
- if (count < 32) {
- HI_WORD(*dest) = (HI_WORD(*dest) << count)
- | (LO_WORD(*dest) >> count);
- LO_WORD(*dest) <<= count;
- return;
- }
- count -= 32;
- HI_WORD(*dest) = LO_WORD(*dest) << count;
- LO_WORD(*dest) = 0;
-}
-
-static inline void lsr64(int count, unsigned long long *dest)
-{
- if (count < 32) {
- LO_WORD(*dest) = (LO_WORD(*dest) >> count)
- | (HI_WORD(*dest) << (32 - count));
- HI_WORD(*dest) >>= count;
- return;
- }
- count -= 32;
- LO_WORD(*dest) = HI_WORD(*dest) >> count;
- HI_WORD(*dest) = 0;
-}
-#endif
-
static inline void fp_denormalize(struct fp_ext *reg, unsigned int cnt)
{
reg->exp += cnt;
@@ -481,117 +241,6 @@ static inline void fp_dividemant(union fp_mant128 *dest, struct fp_ext *src,
}
}
-#if 0
-static inline unsigned int fp_fls128(union fp_mant128 *src)
-{
- unsigned long data;
- unsigned int res, off;
-
- if ((data = src->m32[0]))
- off = 0;
- else if ((data = src->m32[1]))
- off = 32;
- else if ((data = src->m32[2]))
- off = 64;
- else if ((data = src->m32[3]))
- off = 96;
- else
- return 128;
-
- asm ("bfffo %1{#0,#32},%0" : "=d" (res) : "dm" (data));
- return res + off;
-}
-
-static inline void fp_shiftmant128(union fp_mant128 *src, int shift)
-{
- unsigned long sticky;
-
- switch (shift) {
- case 0:
- return;
- case 1:
- asm volatile ("lsl.l #1,%0"
- : "=d" (src->m32[3]) : "0" (src->m32[3]));
- asm volatile ("roxl.l #1,%0"
- : "=d" (src->m32[2]) : "0" (src->m32[2]));
- asm volatile ("roxl.l #1,%0"
- : "=d" (src->m32[1]) : "0" (src->m32[1]));
- asm volatile ("roxl.l #1,%0"
- : "=d" (src->m32[0]) : "0" (src->m32[0]));
- return;
- case 2 ... 31:
- src->m32[0] = (src->m32[0] << shift) | (src->m32[1] >> (32 - shift));
- src->m32[1] = (src->m32[1] << shift) | (src->m32[2] >> (32 - shift));
- src->m32[2] = (src->m32[2] << shift) | (src->m32[3] >> (32 - shift));
- src->m32[3] = (src->m32[3] << shift);
- return;
- case 32 ... 63:
- shift -= 32;
- src->m32[0] = (src->m32[1] << shift) | (src->m32[2] >> (32 - shift));
- src->m32[1] = (src->m32[2] << shift) | (src->m32[3] >> (32 - shift));
- src->m32[2] = (src->m32[3] << shift);
- src->m32[3] = 0;
- return;
- case 64 ... 95:
- shift -= 64;
- src->m32[0] = (src->m32[2] << shift) | (src->m32[3] >> (32 - shift));
- src->m32[1] = (src->m32[3] << shift);
- src->m32[2] = src->m32[3] = 0;
- return;
- case 96 ... 127:
- shift -= 96;
- src->m32[0] = (src->m32[3] << shift);
- src->m32[1] = src->m32[2] = src->m32[3] = 0;
- return;
- case -31 ... -1:
- shift = -shift;
- sticky = 0;
- if (src->m32[3] << (32 - shift))
- sticky = 1;
- src->m32[3] = (src->m32[3] >> shift) | (src->m32[2] << (32 - shift)) | sticky;
- src->m32[2] = (src->m32[2] >> shift) | (src->m32[1] << (32 - shift));
- src->m32[1] = (src->m32[1] >> shift) | (src->m32[0] << (32 - shift));
- src->m32[0] = (src->m32[0] >> shift);
- return;
- case -63 ... -32:
- shift = -shift - 32;
- sticky = 0;
- if ((src->m32[2] << (32 - shift)) || src->m32[3])
- sticky = 1;
- src->m32[3] = (src->m32[2] >> shift) | (src->m32[1] << (32 - shift)) | sticky;
- src->m32[2] = (src->m32[1] >> shift) | (src->m32[0] << (32 - shift));
- src->m32[1] = (src->m32[0] >> shift);
- src->m32[0] = 0;
- return;
- case -95 ... -64:
- shift = -shift - 64;
- sticky = 0;
- if ((src->m32[1] << (32 - shift)) || src->m32[2] || src->m32[3])
- sticky = 1;
- src->m32[3] = (src->m32[1] >> shift) | (src->m32[0] << (32 - shift)) | sticky;
- src->m32[2] = (src->m32[0] >> shift);
- src->m32[1] = src->m32[0] = 0;
- return;
- case -127 ... -96:
- shift = -shift - 96;
- sticky = 0;
- if ((src->m32[0] << (32 - shift)) || src->m32[1] || src->m32[2] || src->m32[3])
- sticky = 1;
- src->m32[3] = (src->m32[0] >> shift) | sticky;
- src->m32[2] = src->m32[1] = src->m32[0] = 0;
- return;
- }
-
- if (shift < 0 && (src->m32[0] || src->m32[1] || src->m32[2] || src->m32[3]))
- src->m32[3] = 1;
- else
- src->m32[3] = 0;
- src->m32[2] = 0;
- src->m32[1] = 0;
- src->m32[0] = 0;
-}
-#endif
-
static inline void fp_putmant128(struct fp_ext *dest, union fp_mant128 *src,
int shift)
{
@@ -637,183 +286,4 @@ static inline void fp_putmant128(struct fp_ext *dest, union fp_mant128 *src,
}
}
-#if 0 /* old code... */
-static inline int fls(unsigned int a)
-{
- int r;
-
- asm volatile ("bfffo %1{#0,#32},%0"
- : "=d" (r) : "md" (a));
- return r;
-}
-
-/* fls = "find last set" (cf. ffs(3)) */
-static inline int fls128(const int128 a)
-{
- if (a[MSW128])
- return fls(a[MSW128]);
- if (a[NMSW128])
- return fls(a[NMSW128]) + 32;
- /* XXX: it probably never gets beyond this point in actual
- use, but that's indicative of a more general problem in the
- algorithm (i.e. as per the actual 68881 implementation, we
- really only need at most 67 bits of precision [plus
- overflow]) so I'm not going to fix it. */
- if (a[NLSW128])
- return fls(a[NLSW128]) + 64;
- if (a[LSW128])
- return fls(a[LSW128]) + 96;
- else
- return -1;
-}
-
-static inline int zerop128(const int128 a)
-{
- return !(a[LSW128] | a[NLSW128] | a[NMSW128] | a[MSW128]);
-}
-
-static inline int nonzerop128(const int128 a)
-{
- return (a[LSW128] | a[NLSW128] | a[NMSW128] | a[MSW128]);
-}
-
-/* Addition and subtraction */
-/* Do these in "pure" assembly, because "extended" asm is unmanageable
- here */
-static inline void add128(const int128 a, int128 b)
-{
- /* rotating carry flags */
- unsigned int carry[2];
-
- carry[0] = a[LSW128] > (0xffffffff - b[LSW128]);
- b[LSW128] += a[LSW128];
-
- carry[1] = a[NLSW128] > (0xffffffff - b[NLSW128] - carry[0]);
- b[NLSW128] = a[NLSW128] + b[NLSW128] + carry[0];
-
- carry[0] = a[NMSW128] > (0xffffffff - b[NMSW128] - carry[1]);
- b[NMSW128] = a[NMSW128] + b[NMSW128] + carry[1];
-
- b[MSW128] = a[MSW128] + b[MSW128] + carry[0];
-}
-
-/* Note: assembler semantics: "b -= a" */
-static inline void sub128(const int128 a, int128 b)
-{
- /* rotating borrow flags */
- unsigned int borrow[2];
-
- borrow[0] = b[LSW128] < a[LSW128];
- b[LSW128] -= a[LSW128];
-
- borrow[1] = b[NLSW128] < a[NLSW128] + borrow[0];
- b[NLSW128] = b[NLSW128] - a[NLSW128] - borrow[0];
-
- borrow[0] = b[NMSW128] < a[NMSW128] + borrow[1];
- b[NMSW128] = b[NMSW128] - a[NMSW128] - borrow[1];
-
- b[MSW128] = b[MSW128] - a[MSW128] - borrow[0];
-}
-
-/* Poor man's 64-bit expanding multiply */
-static inline void mul64(unsigned long long a, unsigned long long b, int128 c)
-{
- unsigned long long acc;
- int128 acc128;
-
- zero128(acc128);
- zero128(c);
-
- /* first the low words */
- if (LO_WORD(a) && LO_WORD(b)) {
- acc = (long long) LO_WORD(a) * LO_WORD(b);
- c[NLSW128] = HI_WORD(acc);
- c[LSW128] = LO_WORD(acc);
- }
- /* Next the high words */
- if (HI_WORD(a) && HI_WORD(b)) {
- acc = (long long) HI_WORD(a) * HI_WORD(b);
- c[MSW128] = HI_WORD(acc);
- c[NMSW128] = LO_WORD(acc);
- }
- /* The middle words */
- if (LO_WORD(a) && HI_WORD(b)) {
- acc = (long long) LO_WORD(a) * HI_WORD(b);
- acc128[NMSW128] = HI_WORD(acc);
- acc128[NLSW128] = LO_WORD(acc);
- add128(acc128, c);
- }
- /* The first and last words */
- if (HI_WORD(a) && LO_WORD(b)) {
- acc = (long long) HI_WORD(a) * LO_WORD(b);
- acc128[NMSW128] = HI_WORD(acc);
- acc128[NLSW128] = LO_WORD(acc);
- add128(acc128, c);
- }
-}
-
-/* Note: unsigned */
-static inline int cmp128(int128 a, int128 b)
-{
- if (a[MSW128] < b[MSW128])
- return -1;
- if (a[MSW128] > b[MSW128])
- return 1;
- if (a[NMSW128] < b[NMSW128])
- return -1;
- if (a[NMSW128] > b[NMSW128])
- return 1;
- if (a[NLSW128] < b[NLSW128])
- return -1;
- if (a[NLSW128] > b[NLSW128])
- return 1;
-
- return (signed) a[LSW128] - b[LSW128];
-}
-
-inline void div128(int128 a, int128 b, int128 c)
-{
- int128 mask;
-
- /* Algorithm:
-
- Shift the divisor until it's at least as big as the
- dividend, keeping track of the position to which we've
- shifted it, i.e. the power of 2 which we've multiplied it
- by.
-
- Then, for this power of 2 (the mask), and every one smaller
- than it, subtract the mask from the dividend and add it to
- the quotient until the dividend is smaller than the raised
- divisor. At this point, divide the dividend and the mask
- by 2 (i.e. shift one place to the right). Lather, rinse,
- and repeat, until there are no more powers of 2 left. */
-
- /* FIXME: needless to say, there's room for improvement here too. */
-
- /* Shift up */
- /* XXX: since it just has to be "at least as big", we can
- probably eliminate this horribly wasteful loop. I will
- have to prove this first, though */
- set128(0, 0, 0, 1, mask);
- while (cmp128(b, a) < 0 && !btsthi128(b)) {
- lslone128(b);
- lslone128(mask);
- }
-
- /* Shift down */
- zero128(c);
- do {
- if (cmp128(a, b) >= 0) {
- sub128(b, a);
- add128(mask, c);
- }
- lsrone128(mask);
- lsrone128(b);
- } while (nonzerop128(mask));
-
- /* The remainder is in a... */
-}
-#endif
-
#endif /* MULTI_ARITH_H */