6.60.22.5 Basic PowerPC Built-in Functions Available on ISA 3.0

The basic built-in functions described in this section are available on the PowerPC family of processors starting with ISA 3.0 or later. Unless specific options are explicitly disabled on the command line, specifying option -mcpu=power9 has the effect of enabling all the same options as for -mcpu=power8 in addition to the -misel option.

The following built-in functions are available on Linux 64-bit systems that use the ISA 3.0 instruction set (-mcpu=power9):

__float128 __builtin_addf128_round_to_odd (__float128, __float128)

Perform a 128-bit IEEE floating point add using round to odd as the rounding mode.

__float128 __builtin_subf128_round_to_odd (__float128, __float128)

Perform a 128-bit IEEE floating point subtract using round to odd as the rounding mode.

__float128 __builtin_mulf128_round_to_odd (__float128, __float128)

Perform a 128-bit IEEE floating point multiply using round to odd as the rounding mode.

__float128 __builtin_divf128_round_to_odd (__float128, __float128)

Perform a 128-bit IEEE floating point divide using round to odd as the rounding mode.

__float128 __builtin_sqrtf128_round_to_odd (__float128)

Perform a 128-bit IEEE floating point square root using round to odd as the rounding mode.

__float128 __builtin_fmaf128_round_to_odd (__float128, __float128, __float128)

Perform a 128-bit IEEE floating point fused multiply and add operation using round to odd as the rounding mode.

double __builtin_truncf128_round_to_odd (__float128)

Convert a 128-bit IEEE floating point value to double using round to odd as the rounding mode.

The following additional built-in functions are also available for the PowerPC family of processors, starting with ISA 3.0 or later:

long long __builtin_darn (void);
long long __builtin_darn_raw (void);
int __builtin_darn_32 (void);

The __builtin_darn and __builtin_darn_raw functions require a 64-bit environment supporting ISA 3.0 or later. The __builtin_darn function provides a 64-bit conditioned random number. The __builtin_darn_raw function provides a 64-bit raw random number. The __builtin_darn_32 function provides a 32-bit conditioned random number.

The following additional built-in functions are also available for the PowerPC family of processors, starting with ISA 3.0 or later:

int __builtin_byte_in_set (unsigned char u, unsigned long long set);
int __builtin_byte_in_range (unsigned char u, unsigned int range);
int __builtin_byte_in_either_range (unsigned char u, unsigned int ranges);

int __builtin_dfp_dtstsfi_lt (unsigned int comparison, _Decimal64 value);
int __builtin_dfp_dtstsfi_lt (unsigned int comparison, _Decimal128 value);
int __builtin_dfp_dtstsfi_lt_dd (unsigned int comparison, _Decimal64 value);
int __builtin_dfp_dtstsfi_lt_td (unsigned int comparison, _Decimal128 value);

int __builtin_dfp_dtstsfi_gt (unsigned int comparison, _Decimal64 value);
int __builtin_dfp_dtstsfi_gt (unsigned int comparison, _Decimal128 value);
int __builtin_dfp_dtstsfi_gt_dd (unsigned int comparison, _Decimal64 value);
int __builtin_dfp_dtstsfi_gt_td (unsigned int comparison, _Decimal128 value);

int __builtin_dfp_dtstsfi_eq (unsigned int comparison, _Decimal64 value);
int __builtin_dfp_dtstsfi_eq (unsigned int comparison, _Decimal128 value);
int __builtin_dfp_dtstsfi_eq_dd (unsigned int comparison, _Decimal64 value);
int __builtin_dfp_dtstsfi_eq_td (unsigned int comparison, _Decimal128 value);

int __builtin_dfp_dtstsfi_ov (unsigned int comparison, _Decimal64 value);
int __builtin_dfp_dtstsfi_ov (unsigned int comparison, _Decimal128 value);
int __builtin_dfp_dtstsfi_ov_dd (unsigned int comparison, _Decimal64 value);
int __builtin_dfp_dtstsfi_ov_td (unsigned int comparison, _Decimal128 value);

double __builtin_mffsl(void);

The __builtin_byte_in_set function requires a 64-bit environment supporting ISA 3.0 or later. This function returns a non-zero value if and only if its u argument exactly equals one of the eight bytes contained within its 64-bit set argument.

The __builtin_byte_in_range and __builtin_byte_in_either_range require an environment supporting ISA 3.0 or later. For these two functions, the range argument is encoded as 4 bytes, organized as hi_1:lo_1:hi_2:lo_2. The __builtin_byte_in_range function returns a non-zero value if and only if its u argument is within the range bounded between lo_2 and hi_2 inclusive. The __builtin_byte_in_either_range function returns non-zero if and only if its u argument is within either the range bounded between lo_1 and hi_1 inclusive or the range bounded between lo_2 and hi_2 inclusive.

The __builtin_dfp_dtstsfi_lt function returns a non-zero value if and only if the number of signficant digits of its value argument is less than its comparison argument. The __builtin_dfp_dtstsfi_lt_dd and __builtin_dfp_dtstsfi_lt_td functions behave similarly, but require that the type of the value argument be __Decimal64 and __Decimal128 respectively.

The __builtin_dfp_dtstsfi_gt function returns a non-zero value if and only if the number of signficant digits of its value argument is greater than its comparison argument. The __builtin_dfp_dtstsfi_gt_dd and __builtin_dfp_dtstsfi_gt_td functions behave similarly, but require that the type of the value argument be __Decimal64 and __Decimal128 respectively.

The __builtin_dfp_dtstsfi_eq function returns a non-zero value if and only if the number of signficant digits of its value argument equals its comparison argument. The __builtin_dfp_dtstsfi_eq_dd and __builtin_dfp_dtstsfi_eq_td functions behave similarly, but require that the type of the value argument be __Decimal64 and __Decimal128 respectively.

The __builtin_dfp_dtstsfi_ov function returns a non-zero value if and only if its value argument has an undefined number of significant digits, such as when value is an encoding of NaN. The __builtin_dfp_dtstsfi_ov_dd and __builtin_dfp_dtstsfi_ov_td functions behave similarly, but require that the type of the value argument be __Decimal64 and __Decimal128 respectively.

The __builtin_mffsl uses the ISA 3.0 mffsl instruction to read the FPSCR. The instruction is a lower latency version of the mffs instruction. If the mffsl instruction is not available, then the builtin uses the older mffs instruction to read the FPSCR.