diff options
Diffstat (limited to 'gst/gstutils.c')
| -rw-r--r-- | gst/gstutils.c | 95 |
1 files changed, 43 insertions, 52 deletions
diff --git a/gst/gstutils.c b/gst/gstutils.c index eeea4bfd9..1938030fd 100644 --- a/gst/gstutils.c +++ b/gst/gstutils.c @@ -258,19 +258,20 @@ gst_util_uint64_mul_uint64 (GstUInt64 * c1, GstUInt64 * c0, guint64 arg1, } #endif /* defined (__x86_64__) */ -/* count leading zeros */ #if defined (__x86_64__) && defined (__GNUC__) -static inline guint -gst_util_clz (guint32 val) +static inline guint64 +gst_util_div128_64 (GstUInt64 c1, GstUInt64 c0, guint64 denom) { - guint s; + guint64 res; - __asm__ __volatile__ ("bsrl %0, %0 \n\t" - "xor $31, %0 \n\t":"=r" (s):"0" (val) + __asm__ __volatile__ ("divq %3":"=a" (res) + :"d" (c1.ll), "a" (c0.ll), "g" (denom) ); - return s; + + return res; } -#else /* defined (__x86_64__) */ +#else +/* count leading zeros */ static inline guint gst_util_clz (guint32 val) { @@ -289,7 +290,6 @@ gst_util_clz (guint32 val) return s; } -#endif /* defined (__x86_64__) */ /* based on Hacker's Delight p152 */ static inline guint64 @@ -349,48 +349,7 @@ gst_util_div128_64 (GstUInt64 c1, GstUInt64 c0, guint64 denom) return q0.ll; } - -/* multiply a 64-bit unsigned int by a 32-bit unsigned int into a 96-bit - * unsigned int. the high 64 bits and low 32 bits of the product are - * placed in c1 and c0 respectively. this operation cannot overflow. */ -#if defined (__x86_64__) && defined (__GNUC__) -static inline void -gst_util_uint64_mul_uint32 (GstUInt64 * c1, GstUInt64 * c0, guint64 arg1, - guint32 arg2) -{ - __asm__ __volatile__ ("mul %%rcx \n\t" - "mov %%rax, %%rcx \n\t" - "shl $32, %%rdx \n\t" - "shr $32, %%rcx \n\t" - "or %%rcx, %%rdx \n\t" - "and $0xffffffff, %%eax \n\t":"=a" (c0->ll), "=d" (c1->ll) - :"a" (arg1), "c" ((guint64) arg2) - ); -} -#else /* defined (__x86_64__) */ -static inline void -gst_util_uint64_mul_uint32 (GstUInt64 * c1, GstUInt64 * c0, guint64 arg1, - guint32 arg2) -{ - GstUInt64 a; - - a.ll = arg1; - - c0->ll = (guint64) a.l.low * arg2; - c1->ll = (guint64) a.l.high * arg2 + c0->l.high; - c0->l.high = 0; -} -#endif /* defined (__x86_64__) */ - -/* divide a 96-bit unsigned int by a 32-bit unsigned int when we know the - * quotient fits into 64 bits. the high 64 bits and low 32 bits of the - * numerator are expected in c1 and c0 respectively. */ -static inline guint64 -gst_util_div96_32 (guint64 c1, guint64 c0, guint32 denom) -{ - c0 += (c1 % denom) << 32; - return ((c1 / denom) << 32) + (c0 / denom); -} +#endif /* defined (__GNUC__) */ /* add correction with carry */ #define CORRECT(c0,c1,val) \ @@ -424,6 +383,30 @@ gst_util_uint64_scale_uint64_unchecked (guint64 val, guint64 num, return gst_util_div128_64 (c1, c0, denom); } +#if !defined (__x86_64__) +static inline void +gst_util_uint64_mul_uint32 (GstUInt64 * c1, GstUInt64 * c0, guint64 arg1, + guint32 arg2) +{ + GstUInt64 a; + + a.ll = arg1; + + c0->ll = (guint64) a.l.low * arg2; + c1->ll = (guint64) a.l.high * arg2 + c0->l.high; + c0->l.high = 0; +} + +/* divide a 96-bit unsigned int by a 32-bit unsigned int when we know the + * quotient fits into 64 bits. the high 64 bits and low 32 bits of the + * numerator are expected in c1 and c0 respectively. */ +static inline guint64 +gst_util_div96_32 (guint64 c1, guint64 c0, guint32 denom) +{ + c0 += (c1 % denom) << 32; + return ((c1 / denom) << 32) + (c0 / denom); +} + static inline guint64 gst_util_uint64_scale_uint32_unchecked (guint64 val, guint32 num, guint32 denom, guint32 correct) @@ -443,6 +426,7 @@ gst_util_uint64_scale_uint32_unchecked (guint64 val, guint32 num, /* compute quotient, fits in 64 bits */ return gst_util_div96_32 (c1.ll, c0.ll, denom); } +#endif /* the guts of the gst_util_uint64_scale() variants */ static guint64 @@ -457,6 +441,8 @@ _gst_util_uint64_scale (guint64 val, guint64 num, guint64 denom, if (G_UNLIKELY (num == denom)) return val; + /* on 64bits we always use a full 128bits multipy/division */ +#if !defined (__x86_64__) /* denom is low --> try to use 96 bit muldiv */ if (G_LIKELY (denom <= G_MAXUINT32)) { /* num is low --> use 96 bit muldiv */ @@ -469,6 +455,7 @@ _gst_util_uint64_scale (guint64 val, guint64 num, guint64 denom, return gst_util_uint64_scale_uint32_unchecked (num, (guint32) val, (guint32) denom, correct); } +#endif /* !defined (__x86_64__) */ /* val is high and num is high --> use 128-bit muldiv */ return gst_util_uint64_scale_uint64_unchecked (val, num, denom, correct); @@ -573,10 +560,14 @@ _gst_util_uint64_scale_int (guint64 val, gint num, gint denom, gint correct) return val / (guint64) denom; } - +#if !defined (__x86_64__) /* num and denom are not negative so casts are OK */ return gst_util_uint64_scale_uint32_unchecked (val, (guint32) num, (guint32) denom, (guint32) correct); +#else + /* always use full 128bits scale */ + return gst_util_uint64_scale_uint64_unchecked (val, num, denom, correct); +#endif } /** |