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[FAST486]

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- Fix the FPU constants.
- Fix rounding.
- Fix FSCALE.


svn path=/trunk/; revision=67873
This commit is contained in:
Aleksandar Andrejevic 2015-05-23 20:26:32 +00:00
parent 35e73601a0
commit fe6672870b
1 changed files with 16 additions and 10 deletions
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26
reactos/lib/fast486/fpu.c
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@ -39,19 +39,19 @@ static const FAST486_FPU_DATA_REG FpuZero = {0ULL, 0, FALSE};
static const FAST486_FPU_DATA_REG FpuOne = {0x8000000000000000ULL, FPU_REAL10_BIAS, FALSE}; static const FAST486_FPU_DATA_REG FpuOne = {0x8000000000000000ULL, FPU_REAL10_BIAS, FALSE};
/* Pi */ /* Pi */
static const FAST486_FPU_DATA_REG FpuPi = {0xC90FDAA22168C234ULL, FPU_REAL10_BIAS + 1, FALSE}; static const FAST486_FPU_DATA_REG FpuPi = {0xC90FDAA22168C235ULL, FPU_REAL10_BIAS + 1, FALSE};
/* lb(10) */ /* lb(10) */
static const FAST486_FPU_DATA_REG FpuL2Ten = {0xD49A784BCD1D8AFEULL, FPU_REAL10_BIAS + 1, FALSE}; static const FAST486_FPU_DATA_REG FpuL2Ten = {0xD49A784BCD1B8AFEULL, FPU_REAL10_BIAS + 1, FALSE};
/* lb(e) */ /* lb(e) */
static const FAST486_FPU_DATA_REG FpuL2E = {0xB8AA3B295C17F0BBULL, FPU_REAL10_BIAS, FALSE}; static const FAST486_FPU_DATA_REG FpuL2E = {0xB8AA3B295C17F0BCULL, FPU_REAL10_BIAS, FALSE};
/* lg(2) */ /* lg(2) */
static const FAST486_FPU_DATA_REG FpuLgTwo = {0x9A209A84FBCFF798ULL, FPU_REAL10_BIAS - 2, FALSE}; static const FAST486_FPU_DATA_REG FpuLgTwo = {0x9A209A84FBCFF799ULL, FPU_REAL10_BIAS - 2, FALSE};
/* ln(2) */ /* ln(2) */
static const FAST486_FPU_DATA_REG FpuLnTwo = {0xB17217F7D1CF79ABULL, FPU_REAL10_BIAS - 1, FALSE}; static const FAST486_FPU_DATA_REG FpuLnTwo = {0xB17217F7D1CF79ACULL, FPU_REAL10_BIAS - 1, FALSE};
/* 2.00 */ /* 2.00 */
static const FAST486_FPU_DATA_REG FpuTwo = {0x8000000000000000ULL, FPU_REAL10_BIAS + 1, FALSE}; static const FAST486_FPU_DATA_REG FpuTwo = {0x8000000000000000ULL, FPU_REAL10_BIAS + 1, FALSE};
@ -246,10 +246,10 @@ Fast486FpuRound(PFAST486_STATE State,
(*Result)++; (*Result)++;
/* Check if all the other bits are clear */ /* Check if all the other bits are clear */
if (!(Remainder & ((1ULL << RemainderHighBit) - 1))) if (!(Remainder & ((1ULL << RemainderHighBit) - 1ULL)))
{ {
/* Round to even */ /* Round to even */
*Result &= ~1; *Result &= ~1ULL;
} }
} }
@ -336,7 +336,7 @@ Fast486FpuToInteger(PFAST486_STATE State,
/* Calculate the result and the remainder */ /* Calculate the result and the remainder */
*Result = (LONGLONG)(Value->Mantissa >> Bits); *Result = (LONGLONG)(Value->Mantissa >> Bits);
Remainder = Value->Mantissa & ((1 << Bits) - 1); Remainder = Value->Mantissa & ((1ULL << Bits) - 1);
} }
else else
{ {
@ -548,7 +548,7 @@ Fast486FpuToDoubleReal(PFAST486_STATE State,
} }
/* Calculate the remainder */ /* Calculate the remainder */
Remainder = Value->Mantissa & ((1 << 11) - 1); Remainder = Value->Mantissa & ((1ULL << 11) - 1ULL);
/* Store the biased exponent */ /* Store the biased exponent */
*Result |= (ULONGLONG)(UnbiasedExp + FPU_REAL8_BIAS) << 52; *Result |= (ULONGLONG)(UnbiasedExp + FPU_REAL8_BIAS) << 52;
@ -1075,7 +1075,7 @@ Fast486FpuCalculateTwoPowerMinusOne(PFAST486_STATE State,
if (!Fast486FpuMultiply(State, &Value, &FpuLnTwo, &Value)) return; if (!Fast486FpuMultiply(State, &Value, &FpuLnTwo, &Value)) return;
if (!Fast486FpuAdd(State, &Value, &Value, &SeriesElement)) return; if (!Fast486FpuAdd(State, &Value, &Value, &SeriesElement)) return;
for (i = 2; i <= INVERSE_NUMBERS_COUNT / 2; i++) for (i = 2; i <= INVERSE_NUMBERS_COUNT; i++)
{ {
/* Add the series element to the final sum */ /* Add the series element to the final sum */
if (!Fast486FpuAdd(State, &TempResult, &SeriesElement, &TempResult)) if (!Fast486FpuAdd(State, &TempResult, &SeriesElement, &TempResult))
@ -2195,6 +2195,7 @@ FAST486_OPCODE_HANDLER(Fast486FpuOpcodeD9)
{ {
LONGLONG Scale; LONGLONG Scale;
LONGLONG UnbiasedExp = (LONGLONG)((SHORT)FPU_ST(0).Exponent) - FPU_REAL10_BIAS; LONGLONG UnbiasedExp = (LONGLONG)((SHORT)FPU_ST(0).Exponent) - FPU_REAL10_BIAS;
INT OldRoundingMode = State->FpuControl.Rc;
FPU_SAVE_LAST_INST(); FPU_SAVE_LAST_INST();
@ -2217,12 +2218,17 @@ FAST486_OPCODE_HANDLER(Fast486FpuOpcodeD9)
} }
} }
State->FpuControl.Rc = FPU_ROUND_TRUNCATE;
if (!Fast486FpuToInteger(State, &FPU_ST(1), &Scale)) if (!Fast486FpuToInteger(State, &FPU_ST(1), &Scale))
{ {
/* Exception occurred */ /* Exception occurred */
State->FpuControl.Rc = OldRoundingMode;
break; break;
} }
State->FpuControl.Rc = OldRoundingMode;
/* Adjust the unbiased exponent */ /* Adjust the unbiased exponent */
UnbiasedExp += Scale; UnbiasedExp += Scale;