X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=rts%2FStgPrimFloat.c;h=80f10e103cac82bbdf6342c6e35c9b536376b472;hp=95210948872edf01f00d379dafbeb635db21caff;hb=842e9d6628a27cf1f420d53f6a5901935dc50c54;hpb=51f782f416a8aa05153a9f2dcef34d8bcb79f1ed diff --git a/rts/StgPrimFloat.c b/rts/StgPrimFloat.c index 9521094..80f10e1 100644 --- a/rts/StgPrimFloat.c +++ b/rts/StgPrimFloat.c @@ -80,6 +80,29 @@ __encodeDouble (I_ size, StgByteArray ba, I_ e) /* result = s * 2^e */ return r; } +StgDouble +__2Int_encodeDouble (I_ j_high, I_ j_low, I_ e) +{ + StgDouble r; + + /* assuming 32 bit ints */ + ASSERT(sizeof(int ) == 4 ); + + r = (StgDouble)((unsigned int)j_high); + r *= 4294967296.0; /* exp2f(32); */ + r += (StgDouble)((unsigned int)j_low); + + /* Now raise to the exponent */ + if ( r != 0.0 ) /* Lennart suggests this avoids a bug in MIPS's ldexp */ + r = ldexp(r, e); + + /* sign is encoded in the size */ + if (j_high < 0) + r = -r; + + return r; +} + /* Special version for small Integers */ StgDouble __int_encodeDouble (I_ j, I_ e) @@ -203,6 +226,53 @@ __decodeDouble (MP_INT *man, I_ *exp, StgDouble dbl) } void +__decodeDouble_2Int (I_ *man_high, I_ *man_low, I_ *exp, StgDouble dbl) +{ + /* Do some bit fiddling on IEEE */ + unsigned int low, high; /* assuming 32 bit ints */ + int sign, iexp; + union { double d; unsigned int i[2]; } u; /* assuming 32 bit ints, 64 bit double */ + + ASSERT(sizeof(unsigned int ) == 4 ); + ASSERT(sizeof(dbl ) == 8 ); + ASSERT(sizeof(dbl ) == SIZEOF_DOUBLE); + + u.d = dbl; /* grab chunks of the double */ + low = u.i[L]; + high = u.i[H]; + + if (low == 0 && (high & ~DMSBIT) == 0) { + *man_low = 0; + *man_high = 0; + *exp = 0L; + } else { + iexp = ((high >> 20) & 0x7ff) + MY_DMINEXP; + sign = high; + + high &= DHIGHBIT-1; + if (iexp != MY_DMINEXP) /* don't add hidden bit to denorms */ + high |= DHIGHBIT; + else { + iexp++; + /* A denorm, normalize the mantissa */ + while (! (high & DHIGHBIT)) { + high <<= 1; + if (low & DMSBIT) + high++; + low <<= 1; + iexp--; + } + } + *exp = (I_) iexp; + *man_low = low; + *man_high = high; + if (sign < 0) { + *man_high = - *man_high; + } + } +} + +void __decodeFloat (MP_INT *man, I_ *exp, StgFloat flt) { /* Do some bit fiddling on IEEE */ @@ -255,6 +325,44 @@ __decodeFloat (MP_INT *man, I_ *exp, StgFloat flt) based on defs in GNU libc */ +void +__decodeFloat_Int (I_ *man, I_ *exp, StgFloat flt) +{ + /* Do some bit fiddling on IEEE */ + int high, sign; /* assuming 32 bit ints */ + union { float f; int i; } u; /* assuming 32 bit float and int */ + + ASSERT(sizeof(int ) == 4 ); + ASSERT(sizeof(flt ) == 4 ); + ASSERT(sizeof(flt ) == SIZEOF_FLOAT ); + + u.f = flt; /* grab the float */ + high = u.i; + + if ((high & ~FMSBIT) == 0) { + *man = 0; + *exp = 0; + } else { + *exp = ((high >> 23) & 0xff) + MY_FMINEXP; + sign = high; + + high &= FHIGHBIT-1; + if (*exp != MY_FMINEXP) /* don't add hidden bit to denorms */ + high |= FHIGHBIT; + else { + (*exp)++; + /* A denorm, normalize the mantissa */ + while (! (high & FHIGHBIT)) { + high <<= 1; + (*exp)--; + } + } + *man = high; + if (sign < 0) + *man = - *man; + } +} + union stg_ieee754_flt { float f;