diff options
Diffstat (limited to 'compiler-rt/lib/builtins/floatuntitf.c')
| -rw-r--r-- | compiler-rt/lib/builtins/floatuntitf.c | 92 |
1 files changed, 46 insertions, 46 deletions
diff --git a/compiler-rt/lib/builtins/floatuntitf.c b/compiler-rt/lib/builtins/floatuntitf.c index dca071dd2ca..6528f4379da 100644 --- a/compiler-rt/lib/builtins/floatuntitf.c +++ b/compiler-rt/lib/builtins/floatuntitf.c @@ -22,57 +22,57 @@ * tu_int is a 128 bit integral type */ -/* seee eeee eeee eeee mmmm mmmm mmmm mmmm | mmmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm | - * mmmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm | mmmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm +/* seee eeee eeee eeee mmmm mmmm mmmm mmmm | mmmm mmmm mmmm mmmm mmmm mmmm mmmm + * mmmm | mmmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm | mmmm mmmm mmmm mmmm mmmm + * mmmm mmmm mmmm */ #if defined(CRT_HAS_128BIT) && defined(CRT_LDBL_128BIT) -COMPILER_RT_ABI fp_t -__floatuntitf(tu_int a) { - if (a == 0) - return 0.0; - const unsigned N = sizeof(tu_int) * CHAR_BIT; - int sd = N - __clzti2(a); /* number of significant digits */ - int e = sd - 1; /* exponent */ - if (sd > LDBL_MANT_DIG) { - /* start: 0000000000000000000001xxxxxxxxxxxxxxxxxxxxxxPQxxxxxxxxxxxxxxxxxx - * finish: 000000000000000000000000000000000000001xxxxxxxxxxxxxxxxxxxxxxPQR - * 12345678901234567890123456 - * 1 = msb 1 bit - * P = bit LDBL_MANT_DIG-1 bits to the right of 1 - * Q = bit LDBL_MANT_DIG bits to the right of 1 - * R = "or" of all bits to the right of Q - */ - switch (sd) { - case LDBL_MANT_DIG + 1: - a <<= 1; - break; - case LDBL_MANT_DIG + 2: - break; - default: - a = (a >> (sd - (LDBL_MANT_DIG+2))) | - ((a & ((tu_int)(-1) >> ((N + LDBL_MANT_DIG+2) - sd))) != 0); - }; - /* finish: */ - a |= (a & 4) != 0; /* Or P into R */ - ++a; /* round - this step may add a significant bit */ - a >>= 2; /* dump Q and R */ - /* a is now rounded to LDBL_MANT_DIG or LDBL_MANT_DIG+1 bits */ - if (a & ((tu_int)1 << LDBL_MANT_DIG)) { - a >>= 1; - ++e; - } - /* a is now rounded to LDBL_MANT_DIG bits */ - } else { - a <<= (LDBL_MANT_DIG - sd); - /* a is now rounded to LDBL_MANT_DIG bits */ +COMPILER_RT_ABI fp_t __floatuntitf(tu_int a) { + if (a == 0) + return 0.0; + const unsigned N = sizeof(tu_int) * CHAR_BIT; + int sd = N - __clzti2(a); /* number of significant digits */ + int e = sd - 1; /* exponent */ + if (sd > LDBL_MANT_DIG) { + /* start: 0000000000000000000001xxxxxxxxxxxxxxxxxxxxxxPQxxxxxxxxxxxxxxxxxx + * finish: 000000000000000000000000000000000000001xxxxxxxxxxxxxxxxxxxxxxPQR + * 12345678901234567890123456 + * 1 = msb 1 bit + * P = bit LDBL_MANT_DIG-1 bits to the right of 1 + * Q = bit LDBL_MANT_DIG bits to the right of 1 + * R = "or" of all bits to the right of Q + */ + switch (sd) { + case LDBL_MANT_DIG + 1: + a <<= 1; + break; + case LDBL_MANT_DIG + 2: + break; + default: + a = (a >> (sd - (LDBL_MANT_DIG + 2))) | + ((a & ((tu_int)(-1) >> ((N + LDBL_MANT_DIG + 2) - sd))) != 0); + }; + /* finish: */ + a |= (a & 4) != 0; /* Or P into R */ + ++a; /* round - this step may add a significant bit */ + a >>= 2; /* dump Q and R */ + /* a is now rounded to LDBL_MANT_DIG or LDBL_MANT_DIG+1 bits */ + if (a & ((tu_int)1 << LDBL_MANT_DIG)) { + a >>= 1; + ++e; } + /* a is now rounded to LDBL_MANT_DIG bits */ + } else { + a <<= (LDBL_MANT_DIG - sd); + /* a is now rounded to LDBL_MANT_DIG bits */ + } - long_double_bits fb; - fb.u.high.all = (du_int)(e + 16383) << 48 /* exponent */ - | ((a >> 64) & 0x0000ffffffffffffLL); /* significand */ - fb.u.low.all = (du_int)(a); - return fb.f; + long_double_bits fb; + fb.u.high.all = (du_int)(e + 16383) << 48 /* exponent */ + | ((a >> 64) & 0x0000ffffffffffffLL); /* significand */ + fb.u.low.all = (du_int)(a); + return fb.f; } #endif |
