X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=arch%2Fx86%2Fmath-emu%2Freg_add_sub.c;h=deea48b9f13a41c6807ecde0ca0f7f9d4d39bd60;hb=ee9a3607fb03e804ddf624544105f4e34260c380;hp=7cd3b37ac084e558cd963ae32be90e82e4764e0c;hpb=1ef3e36251e4edc77a48967d015a87ca3c4283ea;p=pandora-kernel.git diff --git a/arch/x86/math-emu/reg_add_sub.c b/arch/x86/math-emu/reg_add_sub.c index 7cd3b37ac084..deea48b9f13a 100644 --- a/arch/x86/math-emu/reg_add_sub.c +++ b/arch/x86/math-emu/reg_add_sub.c @@ -27,7 +27,7 @@ static int add_sub_specials(FPU_REG const *a, u_char taga, u_char signa, FPU_REG const *b, u_char tagb, u_char signb, - FPU_REG *dest, int deststnr, int control_w); + FPU_REG * dest, int deststnr, int control_w); /* Operates on st(0) and st(n), or on st(0) and temporary data. @@ -35,340 +35,299 @@ int add_sub_specials(FPU_REG const *a, u_char taga, u_char signa, */ int FPU_add(FPU_REG const *b, u_char tagb, int deststnr, int control_w) { - FPU_REG *a = &st(0); - FPU_REG *dest = &st(deststnr); - u_char signb = getsign(b); - u_char taga = FPU_gettag0(); - u_char signa = getsign(a); - u_char saved_sign = getsign(dest); - int diff, tag, expa, expb; - - if ( !(taga | tagb) ) - { - expa = exponent(a); - expb = exponent(b); - - valid_add: - /* Both registers are valid */ - if (!(signa ^ signb)) - { - /* signs are the same */ - tag = FPU_u_add(a, b, dest, control_w, signa, expa, expb); - } - else - { - /* The signs are different, so do a subtraction */ - diff = expa - expb; - if (!diff) - { - diff = a->sigh - b->sigh; /* This works only if the ms bits - are identical. */ - if (!diff) - { - diff = a->sigl > b->sigl; - if (!diff) - diff = -(a->sigl < b->sigl); + FPU_REG *a = &st(0); + FPU_REG *dest = &st(deststnr); + u_char signb = getsign(b); + u_char taga = FPU_gettag0(); + u_char signa = getsign(a); + u_char saved_sign = getsign(dest); + int diff, tag, expa, expb; + + if (!(taga | tagb)) { + expa = exponent(a); + expb = exponent(b); + + valid_add: + /* Both registers are valid */ + if (!(signa ^ signb)) { + /* signs are the same */ + tag = + FPU_u_add(a, b, dest, control_w, signa, expa, expb); + } else { + /* The signs are different, so do a subtraction */ + diff = expa - expb; + if (!diff) { + diff = a->sigh - b->sigh; /* This works only if the ms bits + are identical. */ + if (!diff) { + diff = a->sigl > b->sigl; + if (!diff) + diff = -(a->sigl < b->sigl); + } + } + + if (diff > 0) { + tag = + FPU_u_sub(a, b, dest, control_w, signa, + expa, expb); + } else if (diff < 0) { + tag = + FPU_u_sub(b, a, dest, control_w, signb, + expb, expa); + } else { + FPU_copy_to_regi(&CONST_Z, TAG_Zero, deststnr); + /* sign depends upon rounding mode */ + setsign(dest, ((control_w & CW_RC) != RC_DOWN) + ? SIGN_POS : SIGN_NEG); + return TAG_Zero; + } } - } - - if (diff > 0) - { - tag = FPU_u_sub(a, b, dest, control_w, signa, expa, expb); - } - else if ( diff < 0 ) - { - tag = FPU_u_sub(b, a, dest, control_w, signb, expb, expa); - } - else - { - FPU_copy_to_regi(&CONST_Z, TAG_Zero, deststnr); - /* sign depends upon rounding mode */ - setsign(dest, ((control_w & CW_RC) != RC_DOWN) - ? SIGN_POS : SIGN_NEG); - return TAG_Zero; - } - } - if ( tag < 0 ) - { - setsign(dest, saved_sign); - return tag; + if (tag < 0) { + setsign(dest, saved_sign); + return tag; + } + FPU_settagi(deststnr, tag); + return tag; } - FPU_settagi(deststnr, tag); - return tag; - } - if ( taga == TAG_Special ) - taga = FPU_Special(a); - if ( tagb == TAG_Special ) - tagb = FPU_Special(b); + if (taga == TAG_Special) + taga = FPU_Special(a); + if (tagb == TAG_Special) + tagb = FPU_Special(b); - if ( ((taga == TAG_Valid) && (tagb == TW_Denormal)) + if (((taga == TAG_Valid) && (tagb == TW_Denormal)) || ((taga == TW_Denormal) && (tagb == TAG_Valid)) - || ((taga == TW_Denormal) && (tagb == TW_Denormal)) ) - { - FPU_REG x, y; + || ((taga == TW_Denormal) && (tagb == TW_Denormal))) { + FPU_REG x, y; + + if (denormal_operand() < 0) + return FPU_Exception; + + FPU_to_exp16(a, &x); + FPU_to_exp16(b, &y); + a = &x; + b = &y; + expa = exponent16(a); + expb = exponent16(b); + goto valid_add; + } - if ( denormal_operand() < 0 ) - return FPU_Exception; + if ((taga == TW_NaN) || (tagb == TW_NaN)) { + if (deststnr == 0) + return real_2op_NaN(b, tagb, deststnr, a); + else + return real_2op_NaN(a, taga, deststnr, a); + } - FPU_to_exp16(a, &x); - FPU_to_exp16(b, &y); - a = &x; - b = &y; - expa = exponent16(a); - expb = exponent16(b); - goto valid_add; - } - - if ( (taga == TW_NaN) || (tagb == TW_NaN) ) - { - if ( deststnr == 0 ) - return real_2op_NaN(b, tagb, deststnr, a); - else - return real_2op_NaN(a, taga, deststnr, a); - } - - return add_sub_specials(a, taga, signa, b, tagb, signb, - dest, deststnr, control_w); + return add_sub_specials(a, taga, signa, b, tagb, signb, + dest, deststnr, control_w); } - /* Subtract b from a. (a-b) -> dest */ int FPU_sub(int flags, int rm, int control_w) { - FPU_REG const *a, *b; - FPU_REG *dest; - u_char taga, tagb, signa, signb, saved_sign, sign; - int diff, tag = 0, expa, expb, deststnr; - - a = &st(0); - taga = FPU_gettag0(); - - deststnr = 0; - if ( flags & LOADED ) - { - b = (FPU_REG *)rm; - tagb = flags & 0x0f; - } - else - { - b = &st(rm); - tagb = FPU_gettagi(rm); - - if ( flags & DEST_RM ) - deststnr = rm; - } - - signa = getsign(a); - signb = getsign(b); - - if ( flags & REV ) - { - signa ^= SIGN_NEG; - signb ^= SIGN_NEG; - } - - dest = &st(deststnr); - saved_sign = getsign(dest); - - if ( !(taga | tagb) ) - { - expa = exponent(a); - expb = exponent(b); - - valid_subtract: - /* Both registers are valid */ - - diff = expa - expb; - - if (!diff) - { - diff = a->sigh - b->sigh; /* Works only if ms bits are identical */ - if (!diff) - { - diff = a->sigl > b->sigl; - if (!diff) - diff = -(a->sigl < b->sigl); - } + FPU_REG const *a, *b; + FPU_REG *dest; + u_char taga, tagb, signa, signb, saved_sign, sign; + int diff, tag = 0, expa, expb, deststnr; + + a = &st(0); + taga = FPU_gettag0(); + + deststnr = 0; + if (flags & LOADED) { + b = (FPU_REG *) rm; + tagb = flags & 0x0f; + } else { + b = &st(rm); + tagb = FPU_gettagi(rm); + + if (flags & DEST_RM) + deststnr = rm; } - switch ( (((int)signa)*2 + signb) / SIGN_NEG ) - { - case 0: /* P - P */ - case 3: /* N - N */ - if (diff > 0) - { - /* |a| > |b| */ - tag = FPU_u_sub(a, b, dest, control_w, signa, expa, expb); - } - else if ( diff == 0 ) - { - FPU_copy_to_regi(&CONST_Z, TAG_Zero, deststnr); - - /* sign depends upon rounding mode */ - setsign(dest, ((control_w & CW_RC) != RC_DOWN) - ? SIGN_POS : SIGN_NEG); - return TAG_Zero; - } - else - { - sign = signa ^ SIGN_NEG; - tag = FPU_u_sub(b, a, dest, control_w, sign, expb, expa); - } - break; - case 1: /* P - N */ - tag = FPU_u_add(a, b, dest, control_w, SIGN_POS, expa, expb); - break; - case 2: /* N - P */ - tag = FPU_u_add(a, b, dest, control_w, SIGN_NEG, expa, expb); - break; + signa = getsign(a); + signb = getsign(b); + + if (flags & REV) { + signa ^= SIGN_NEG; + signb ^= SIGN_NEG; + } + + dest = &st(deststnr); + saved_sign = getsign(dest); + + if (!(taga | tagb)) { + expa = exponent(a); + expb = exponent(b); + + valid_subtract: + /* Both registers are valid */ + + diff = expa - expb; + + if (!diff) { + diff = a->sigh - b->sigh; /* Works only if ms bits are identical */ + if (!diff) { + diff = a->sigl > b->sigl; + if (!diff) + diff = -(a->sigl < b->sigl); + } + } + + switch ((((int)signa) * 2 + signb) / SIGN_NEG) { + case 0: /* P - P */ + case 3: /* N - N */ + if (diff > 0) { + /* |a| > |b| */ + tag = + FPU_u_sub(a, b, dest, control_w, signa, + expa, expb); + } else if (diff == 0) { + FPU_copy_to_regi(&CONST_Z, TAG_Zero, deststnr); + + /* sign depends upon rounding mode */ + setsign(dest, ((control_w & CW_RC) != RC_DOWN) + ? SIGN_POS : SIGN_NEG); + return TAG_Zero; + } else { + sign = signa ^ SIGN_NEG; + tag = + FPU_u_sub(b, a, dest, control_w, sign, expb, + expa); + } + break; + case 1: /* P - N */ + tag = + FPU_u_add(a, b, dest, control_w, SIGN_POS, expa, + expb); + break; + case 2: /* N - P */ + tag = + FPU_u_add(a, b, dest, control_w, SIGN_NEG, expa, + expb); + break; #ifdef PARANOID - default: - EXCEPTION(EX_INTERNAL|0x111); - return -1; + default: + EXCEPTION(EX_INTERNAL | 0x111); + return -1; #endif + } + if (tag < 0) { + setsign(dest, saved_sign); + return tag; + } + FPU_settagi(deststnr, tag); + return tag; } - if ( tag < 0 ) - { - setsign(dest, saved_sign); - return tag; - } - FPU_settagi(deststnr, tag); - return tag; - } - if ( taga == TAG_Special ) - taga = FPU_Special(a); - if ( tagb == TAG_Special ) - tagb = FPU_Special(b); + if (taga == TAG_Special) + taga = FPU_Special(a); + if (tagb == TAG_Special) + tagb = FPU_Special(b); - if ( ((taga == TAG_Valid) && (tagb == TW_Denormal)) + if (((taga == TAG_Valid) && (tagb == TW_Denormal)) || ((taga == TW_Denormal) && (tagb == TAG_Valid)) - || ((taga == TW_Denormal) && (tagb == TW_Denormal)) ) - { - FPU_REG x, y; + || ((taga == TW_Denormal) && (tagb == TW_Denormal))) { + FPU_REG x, y; - if ( denormal_operand() < 0 ) - return FPU_Exception; + if (denormal_operand() < 0) + return FPU_Exception; + + FPU_to_exp16(a, &x); + FPU_to_exp16(b, &y); + a = &x; + b = &y; + expa = exponent16(a); + expb = exponent16(b); - FPU_to_exp16(a, &x); - FPU_to_exp16(b, &y); - a = &x; - b = &y; - expa = exponent16(a); - expb = exponent16(b); - - goto valid_subtract; - } - - if ( (taga == TW_NaN) || (tagb == TW_NaN) ) - { - FPU_REG const *d1, *d2; - if ( flags & REV ) - { - d1 = b; - d2 = a; + goto valid_subtract; } - else - { - d1 = a; - d2 = b; + + if ((taga == TW_NaN) || (tagb == TW_NaN)) { + FPU_REG const *d1, *d2; + if (flags & REV) { + d1 = b; + d2 = a; + } else { + d1 = a; + d2 = b; + } + if (flags & LOADED) + return real_2op_NaN(b, tagb, deststnr, d1); + if (flags & DEST_RM) + return real_2op_NaN(a, taga, deststnr, d2); + else + return real_2op_NaN(b, tagb, deststnr, d2); } - if ( flags & LOADED ) - return real_2op_NaN(b, tagb, deststnr, d1); - if ( flags & DEST_RM ) - return real_2op_NaN(a, taga, deststnr, d2); - else - return real_2op_NaN(b, tagb, deststnr, d2); - } - - return add_sub_specials(a, taga, signa, b, tagb, signb ^ SIGN_NEG, - dest, deststnr, control_w); -} + return add_sub_specials(a, taga, signa, b, tagb, signb ^ SIGN_NEG, + dest, deststnr, control_w); +} static int add_sub_specials(FPU_REG const *a, u_char taga, u_char signa, FPU_REG const *b, u_char tagb, u_char signb, - FPU_REG *dest, int deststnr, int control_w) + FPU_REG * dest, int deststnr, int control_w) { - if ( ((taga == TW_Denormal) || (tagb == TW_Denormal)) - && (denormal_operand() < 0) ) - return FPU_Exception; - - if (taga == TAG_Zero) - { - if (tagb == TAG_Zero) - { - /* Both are zero, result will be zero. */ - u_char different_signs = signa ^ signb; - - FPU_copy_to_regi(a, TAG_Zero, deststnr); - if ( different_signs ) - { - /* Signs are different. */ - /* Sign of answer depends upon rounding mode. */ - setsign(dest, ((control_w & CW_RC) != RC_DOWN) - ? SIGN_POS : SIGN_NEG); - } - else - setsign(dest, signa); /* signa may differ from the sign of a. */ - return TAG_Zero; - } - else - { - reg_copy(b, dest); - if ( (tagb == TW_Denormal) && (b->sigh & 0x80000000) ) - { - /* A pseudoDenormal, convert it. */ - addexponent(dest, 1); - tagb = TAG_Valid; - } - else if ( tagb > TAG_Empty ) - tagb = TAG_Special; - setsign(dest, signb); /* signb may differ from the sign of b. */ - FPU_settagi(deststnr, tagb); - return tagb; - } - } - else if (tagb == TAG_Zero) - { - reg_copy(a, dest); - if ( (taga == TW_Denormal) && (a->sigh & 0x80000000) ) - { - /* A pseudoDenormal */ - addexponent(dest, 1); - taga = TAG_Valid; - } - else if ( taga > TAG_Empty ) - taga = TAG_Special; - setsign(dest, signa); /* signa may differ from the sign of a. */ - FPU_settagi(deststnr, taga); - return taga; - } - else if (taga == TW_Infinity) - { - if ( (tagb != TW_Infinity) || (signa == signb) ) - { - FPU_copy_to_regi(a, TAG_Special, deststnr); - setsign(dest, signa); /* signa may differ from the sign of a. */ - return taga; + if (((taga == TW_Denormal) || (tagb == TW_Denormal)) + && (denormal_operand() < 0)) + return FPU_Exception; + + if (taga == TAG_Zero) { + if (tagb == TAG_Zero) { + /* Both are zero, result will be zero. */ + u_char different_signs = signa ^ signb; + + FPU_copy_to_regi(a, TAG_Zero, deststnr); + if (different_signs) { + /* Signs are different. */ + /* Sign of answer depends upon rounding mode. */ + setsign(dest, ((control_w & CW_RC) != RC_DOWN) + ? SIGN_POS : SIGN_NEG); + } else + setsign(dest, signa); /* signa may differ from the sign of a. */ + return TAG_Zero; + } else { + reg_copy(b, dest); + if ((tagb == TW_Denormal) && (b->sigh & 0x80000000)) { + /* A pseudoDenormal, convert it. */ + addexponent(dest, 1); + tagb = TAG_Valid; + } else if (tagb > TAG_Empty) + tagb = TAG_Special; + setsign(dest, signb); /* signb may differ from the sign of b. */ + FPU_settagi(deststnr, tagb); + return tagb; + } + } else if (tagb == TAG_Zero) { + reg_copy(a, dest); + if ((taga == TW_Denormal) && (a->sigh & 0x80000000)) { + /* A pseudoDenormal */ + addexponent(dest, 1); + taga = TAG_Valid; + } else if (taga > TAG_Empty) + taga = TAG_Special; + setsign(dest, signa); /* signa may differ from the sign of a. */ + FPU_settagi(deststnr, taga); + return taga; + } else if (taga == TW_Infinity) { + if ((tagb != TW_Infinity) || (signa == signb)) { + FPU_copy_to_regi(a, TAG_Special, deststnr); + setsign(dest, signa); /* signa may differ from the sign of a. */ + return taga; + } + /* Infinity-Infinity is undefined. */ + return arith_invalid(deststnr); + } else if (tagb == TW_Infinity) { + FPU_copy_to_regi(b, TAG_Special, deststnr); + setsign(dest, signb); /* signb may differ from the sign of b. */ + return tagb; } - /* Infinity-Infinity is undefined. */ - return arith_invalid(deststnr); - } - else if (tagb == TW_Infinity) - { - FPU_copy_to_regi(b, TAG_Special, deststnr); - setsign(dest, signb); /* signb may differ from the sign of b. */ - return tagb; - } - #ifdef PARANOID - EXCEPTION(EX_INTERNAL|0x101); + EXCEPTION(EX_INTERNAL | 0x101); #endif - return FPU_Exception; + return FPU_Exception; } -