diff options
Diffstat (limited to 'fpu/softfloat-specialize.c.inc')
-rw-r--r-- | fpu/softfloat-specialize.c.inc | 460 |
1 files changed, 27 insertions, 433 deletions
diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index 8f3b97d..ba4fa08 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -85,11 +85,7 @@ this code that are retained. */ static inline bool no_signaling_nans(float_status *status) { -#if defined(TARGET_XTENSA) return status->no_signaling_nans; -#else - return false; -#endif } /* Define how the architecture discriminates signaling NaNs. @@ -97,17 +93,10 @@ static inline bool no_signaling_nans(float_status *status) * In IEEE 754-1985 this was implementation defined, but in IEEE 754-2008 * the msb must be zero. MIPS is (so far) unique in supporting both the * 2008 revision and backward compatibility with their original choice. - * Thus for MIPS we must make the choice at runtime. */ static inline bool snan_bit_is_one(float_status *status) { -#if defined(TARGET_MIPS) return status->snan_bit_is_one; -#elif defined(TARGET_HPPA) || defined(TARGET_SH4) - return 1; -#else - return 0; -#endif } /*---------------------------------------------------------------------------- @@ -133,35 +122,17 @@ static void parts64_default_nan(FloatParts64 *p, float_status *status) { bool sign = 0; uint64_t frac; + uint8_t dnan_pattern = status->default_nan_pattern; -#if defined(TARGET_SPARC) || defined(TARGET_M68K) - /* !snan_bit_is_one, set all bits */ - frac = (1ULL << DECOMPOSED_BINARY_POINT) - 1; -#elif defined(TARGET_I386) || defined(TARGET_X86_64) \ - || defined(TARGET_MICROBLAZE) - /* !snan_bit_is_one, set sign and msb */ - frac = 1ULL << (DECOMPOSED_BINARY_POINT - 1); - sign = 1; -#elif defined(TARGET_HPPA) - /* snan_bit_is_one, set msb-1. */ - frac = 1ULL << (DECOMPOSED_BINARY_POINT - 2); -#elif defined(TARGET_HEXAGON) - sign = 1; - frac = ~0ULL; -#else + assert(dnan_pattern != 0); + + sign = dnan_pattern >> 7; /* - * This case is true for Alpha, ARM, MIPS, OpenRISC, PPC, RISC-V, - * S390, SH4, TriCore, and Xtensa. Our other supported targets, - * such CRIS, do not have floating-point. + * Place default_nan_pattern [6:0] into bits [62:56], + * and replecate bit [0] down into [55:0] */ - if (snan_bit_is_one(status)) { - /* set all bits other than msb */ - frac = (1ULL << (DECOMPOSED_BINARY_POINT - 1)) - 1; - } else { - /* set msb */ - frac = 1ULL << (DECOMPOSED_BINARY_POINT - 1); - } -#endif + frac = deposit64(0, DECOMPOSED_BINARY_POINT - 7, 7, dnan_pattern); + frac = deposit64(frac, 0, DECOMPOSED_BINARY_POINT - 7, -(dnan_pattern & 1)); *p = (FloatParts64) { .cls = float_class_qnan, @@ -227,17 +198,17 @@ static void parts128_silence_nan(FloatParts128 *p, float_status *status) floatx80 floatx80_default_nan(float_status *status) { floatx80 r; + /* + * Extrapolate from the choices made by parts64_default_nan to fill + * in the floatx80 format. We assume that floatx80's explicit + * integer bit is always set (this is true for i386 and m68k, + * which are the only real users of this format). + */ + FloatParts64 p64; + parts64_default_nan(&p64, status); - /* None of the targets that have snan_bit_is_one use floatx80. */ - assert(!snan_bit_is_one(status)); -#if defined(TARGET_M68K) - r.low = UINT64_C(0xFFFFFFFFFFFFFFFF); - r.high = 0x7FFF; -#else - /* X86 */ - r.low = UINT64_C(0xC000000000000000); - r.high = 0xFFFF; -#endif + r.high = 0x7FFF | (p64.sign << 15); + r.low = (1ULL << DECOMPOSED_BINARY_POINT) | p64.frac; return r; } @@ -245,15 +216,15 @@ floatx80 floatx80_default_nan(float_status *status) | The pattern for a default generated extended double-precision inf. *----------------------------------------------------------------------------*/ -#define floatx80_infinity_high 0x7FFF -#if defined(TARGET_M68K) -#define floatx80_infinity_low UINT64_C(0x0000000000000000) -#else -#define floatx80_infinity_low UINT64_C(0x8000000000000000) -#endif - -const floatx80 floatx80_infinity - = make_floatx80_init(floatx80_infinity_high, floatx80_infinity_low); +floatx80 floatx80_default_inf(bool zSign, float_status *status) +{ + /* + * Whether the Integer bit is set in the default Infinity is + * target dependent. + */ + bool z = status->floatx80_behaviour & floatx80_default_inf_int_bit_is_zero; + return packFloatx80(zSign, 0x7fff, z ? 0 : (1ULL << 63)); +} /*---------------------------------------------------------------------------- | Returns 1 if the half-precision floating-point value `a' is a quiet @@ -371,331 +342,6 @@ bool float32_is_signaling_nan(float32 a_, float_status *status) } /*---------------------------------------------------------------------------- -| Select which NaN to propagate for a two-input operation. -| IEEE754 doesn't specify all the details of this, so the -| algorithm is target-specific. -| The routine is passed various bits of information about the -| two NaNs and should return 0 to select NaN a and 1 for NaN b. -| Note that signalling NaNs are always squashed to quiet NaNs -| by the caller, by calling floatXX_silence_nan() before -| returning them. -| -| aIsLargerSignificand is only valid if both a and b are NaNs -| of some kind, and is true if a has the larger significand, -| or if both a and b have the same significand but a is -| positive but b is negative. It is only needed for the x87 -| tie-break rule. -*----------------------------------------------------------------------------*/ - -static int pickNaN(FloatClass a_cls, FloatClass b_cls, - bool aIsLargerSignificand, float_status *status) -{ -#if defined(TARGET_ARM) || defined(TARGET_MIPS) || defined(TARGET_HPPA) || \ - defined(TARGET_LOONGARCH64) || defined(TARGET_S390X) - /* ARM mandated NaN propagation rules (see FPProcessNaNs()), take - * the first of: - * 1. A if it is signaling - * 2. B if it is signaling - * 3. A (quiet) - * 4. B (quiet) - * A signaling NaN is always quietened before returning it. - */ - /* According to MIPS specifications, if one of the two operands is - * a sNaN, a new qNaN has to be generated. This is done in - * floatXX_silence_nan(). For qNaN inputs the specifications - * says: "When possible, this QNaN result is one of the operand QNaN - * values." In practice it seems that most implementations choose - * the first operand if both operands are qNaN. In short this gives - * the following rules: - * 1. A if it is signaling - * 2. B if it is signaling - * 3. A (quiet) - * 4. B (quiet) - * A signaling NaN is always silenced before returning it. - */ - if (is_snan(a_cls)) { - return 0; - } else if (is_snan(b_cls)) { - return 1; - } else if (is_qnan(a_cls)) { - return 0; - } else { - return 1; - } -#elif defined(TARGET_PPC) || defined(TARGET_M68K) - /* PowerPC propagation rules: - * 1. A if it sNaN or qNaN - * 2. B if it sNaN or qNaN - * A signaling NaN is always silenced before returning it. - */ - /* M68000 FAMILY PROGRAMMER'S REFERENCE MANUAL - * 3.4 FLOATING-POINT INSTRUCTION DETAILS - * If either operand, but not both operands, of an operation is a - * nonsignaling NaN, then that NaN is returned as the result. If both - * operands are nonsignaling NaNs, then the destination operand - * nonsignaling NaN is returned as the result. - * If either operand to an operation is a signaling NaN (SNaN), then the - * SNaN bit is set in the FPSR EXC byte. If the SNaN exception enable bit - * is set in the FPCR ENABLE byte, then the exception is taken and the - * destination is not modified. If the SNaN exception enable bit is not - * set, setting the SNaN bit in the operand to a one converts the SNaN to - * a nonsignaling NaN. The operation then continues as described in the - * preceding paragraph for nonsignaling NaNs. - */ - if (is_nan(a_cls)) { - return 0; - } else { - return 1; - } -#elif defined(TARGET_SPARC) - /* Prefer SNaN over QNaN, order B then A. */ - if (is_snan(b_cls)) { - return 1; - } else if (is_snan(a_cls)) { - return 0; - } else if (is_qnan(b_cls)) { - return 1; - } else { - return 0; - } -#elif defined(TARGET_XTENSA) - /* - * Xtensa has two NaN propagation modes. - * Which one is active is controlled by float_status::use_first_nan. - */ - if (status->use_first_nan) { - if (is_nan(a_cls)) { - return 0; - } else { - return 1; - } - } else { - if (is_nan(b_cls)) { - return 1; - } else { - return 0; - } - } -#else - /* This implements x87 NaN propagation rules: - * SNaN + QNaN => return the QNaN - * two SNaNs => return the one with the larger significand, silenced - * two QNaNs => return the one with the larger significand - * SNaN and a non-NaN => return the SNaN, silenced - * QNaN and a non-NaN => return the QNaN - * - * If we get down to comparing significands and they are the same, - * return the NaN with the positive sign bit (if any). - */ - if (is_snan(a_cls)) { - if (is_snan(b_cls)) { - return aIsLargerSignificand ? 0 : 1; - } - return is_qnan(b_cls) ? 1 : 0; - } else if (is_qnan(a_cls)) { - if (is_snan(b_cls) || !is_qnan(b_cls)) { - return 0; - } else { - return aIsLargerSignificand ? 0 : 1; - } - } else { - return 1; - } -#endif -} - -/*---------------------------------------------------------------------------- -| Select which NaN to propagate for a three-input operation. -| For the moment we assume that no CPU needs the 'larger significand' -| information. -| Return values : 0 : a; 1 : b; 2 : c; 3 : default-NaN -*----------------------------------------------------------------------------*/ -static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, - bool infzero, float_status *status) -{ -#if defined(TARGET_ARM) - /* For ARM, the (inf,zero,qnan) case sets InvalidOp and returns - * the default NaN - */ - if (infzero && is_qnan(c_cls)) { - float_raise(float_flag_invalid | float_flag_invalid_imz, status); - return 3; - } - - /* This looks different from the ARM ARM pseudocode, because the ARM ARM - * puts the operands to a fused mac operation (a*b)+c in the order c,a,b. - */ - if (is_snan(c_cls)) { - return 2; - } else if (is_snan(a_cls)) { - return 0; - } else if (is_snan(b_cls)) { - return 1; - } else if (is_qnan(c_cls)) { - return 2; - } else if (is_qnan(a_cls)) { - return 0; - } else { - return 1; - } -#elif defined(TARGET_MIPS) - if (snan_bit_is_one(status)) { - /* - * For MIPS systems that conform to IEEE754-1985, the (inf,zero,nan) - * case sets InvalidOp and returns the default NaN - */ - if (infzero) { - float_raise(float_flag_invalid | float_flag_invalid_imz, status); - return 3; - } - /* Prefer sNaN over qNaN, in the a, b, c order. */ - if (is_snan(a_cls)) { - return 0; - } else if (is_snan(b_cls)) { - return 1; - } else if (is_snan(c_cls)) { - return 2; - } else if (is_qnan(a_cls)) { - return 0; - } else if (is_qnan(b_cls)) { - return 1; - } else { - return 2; - } - } else { - /* - * For MIPS systems that conform to IEEE754-2008, the (inf,zero,nan) - * case sets InvalidOp and returns the input value 'c' - */ - if (infzero) { - float_raise(float_flag_invalid | float_flag_invalid_imz, status); - return 2; - } - /* Prefer sNaN over qNaN, in the c, a, b order. */ - if (is_snan(c_cls)) { - return 2; - } else if (is_snan(a_cls)) { - return 0; - } else if (is_snan(b_cls)) { - return 1; - } else if (is_qnan(c_cls)) { - return 2; - } else if (is_qnan(a_cls)) { - return 0; - } else { - return 1; - } - } -#elif defined(TARGET_LOONGARCH64) - /* - * For LoongArch systems that conform to IEEE754-2008, the (inf,zero,nan) - * case sets InvalidOp and returns the input value 'c' - */ - if (infzero) { - float_raise(float_flag_invalid | float_flag_invalid_imz, status); - return 2; - } - /* Prefer sNaN over qNaN, in the c, a, b order. */ - if (is_snan(c_cls)) { - return 2; - } else if (is_snan(a_cls)) { - return 0; - } else if (is_snan(b_cls)) { - return 1; - } else if (is_qnan(c_cls)) { - return 2; - } else if (is_qnan(a_cls)) { - return 0; - } else { - return 1; - } -#elif defined(TARGET_PPC) - /* For PPC, the (inf,zero,qnan) case sets InvalidOp, but we prefer - * to return an input NaN if we have one (ie c) rather than generating - * a default NaN - */ - if (infzero) { - float_raise(float_flag_invalid | float_flag_invalid_imz, status); - return 2; - } - - /* If fRA is a NaN return it; otherwise if fRB is a NaN return it; - * otherwise return fRC. Note that muladd on PPC is (fRA * fRC) + frB - */ - if (is_nan(a_cls)) { - return 0; - } else if (is_nan(c_cls)) { - return 2; - } else { - return 1; - } -#elif defined(TARGET_RISCV) - /* For RISC-V, InvalidOp is set when multiplicands are Inf and zero */ - if (infzero) { - float_raise(float_flag_invalid | float_flag_invalid_imz, status); - } - return 3; /* default NaN */ -#elif defined(TARGET_SPARC) - /* For (inf,0,nan) return c. */ - if (infzero) { - float_raise(float_flag_invalid | float_flag_invalid_imz, status); - return 2; - } - /* Prefer SNaN over QNaN, order C, B, A. */ - if (is_snan(c_cls)) { - return 2; - } else if (is_snan(b_cls)) { - return 1; - } else if (is_snan(a_cls)) { - return 0; - } else if (is_qnan(c_cls)) { - return 2; - } else if (is_qnan(b_cls)) { - return 1; - } else { - return 0; - } -#elif defined(TARGET_XTENSA) - /* - * For Xtensa, the (inf,zero,nan) case sets InvalidOp and returns - * an input NaN if we have one (ie c). - */ - if (infzero) { - float_raise(float_flag_invalid | float_flag_invalid_imz, status); - return 2; - } - if (status->use_first_nan) { - if (is_nan(a_cls)) { - return 0; - } else if (is_nan(b_cls)) { - return 1; - } else { - return 2; - } - } else { - if (is_nan(c_cls)) { - return 2; - } else if (is_nan(b_cls)) { - return 1; - } else { - return 0; - } - } -#else - /* A default implementation: prefer a to b to c. - * This is unlikely to actually match any real implementation. - */ - if (is_nan(a_cls)) { - return 0; - } else if (is_nan(b_cls)) { - return 1; - } else { - return 2; - } -#endif -} - -/*---------------------------------------------------------------------------- | Returns 1 if the double-precision floating-point value `a' is a quiet | NaN; otherwise returns 0. *----------------------------------------------------------------------------*/ @@ -799,58 +445,6 @@ floatx80 floatx80_silence_nan(floatx80 a, float_status *status) } /*---------------------------------------------------------------------------- -| Takes two extended double-precision floating-point values `a' and `b', one -| of which is a NaN, and returns the appropriate NaN result. If either `a' or -| `b' is a signaling NaN, the invalid exception is raised. -*----------------------------------------------------------------------------*/ - -floatx80 propagateFloatx80NaN(floatx80 a, floatx80 b, float_status *status) -{ - bool aIsLargerSignificand; - FloatClass a_cls, b_cls; - - /* This is not complete, but is good enough for pickNaN. */ - a_cls = (!floatx80_is_any_nan(a) - ? float_class_normal - : floatx80_is_signaling_nan(a, status) - ? float_class_snan - : float_class_qnan); - b_cls = (!floatx80_is_any_nan(b) - ? float_class_normal - : floatx80_is_signaling_nan(b, status) - ? float_class_snan - : float_class_qnan); - - if (is_snan(a_cls) || is_snan(b_cls)) { - float_raise(float_flag_invalid, status); - } - - if (status->default_nan_mode) { - return floatx80_default_nan(status); - } - - if (a.low < b.low) { - aIsLargerSignificand = 0; - } else if (b.low < a.low) { - aIsLargerSignificand = 1; - } else { - aIsLargerSignificand = (a.high < b.high) ? 1 : 0; - } - - if (pickNaN(a_cls, b_cls, aIsLargerSignificand, status)) { - if (is_snan(b_cls)) { - return floatx80_silence_nan(b, status); - } - return b; - } else { - if (is_snan(a_cls)) { - return floatx80_silence_nan(a, status); - } - return a; - } -} - -/*---------------------------------------------------------------------------- | Returns 1 if the quadruple-precision floating-point value `a' is a quiet | NaN; otherwise returns 0. *----------------------------------------------------------------------------*/ |