diff --git a/clang/docs/LanguageExtensions.rst b/clang/docs/LanguageExtensions.rst --- a/clang/docs/LanguageExtensions.rst +++ b/clang/docs/LanguageExtensions.rst @@ -506,6 +506,68 @@ If it's an extension (OpenCL) vector, it's only available in C and OpenCL C. And it selects base on signedness of the condition operands (OpenCL v1.1 s6.3.9). +Vector Builtins +--------------- + +In addition to the operators mentioned above, Clang provides a set of builtins +to perform additional operations on certain scalar and vector types. + +Let ``T`` be one of the following types: + +* an integer type (as in C2x 6.2.5p19), but excluding enumerated types and _Bool +* the standard floating types float or double +* a half-precision floating point type, if one is supported on the target +* a vector type. + +For scalar types, consider the operation applied to a vector with a single element. + +*Elementwise Builtins* + +Each builtin returns a vector equivalent to applying the specified operation +elementwise to the input. + +Unless specified otherwise operation(±0) = ±0 and operation(±infinity) = ±infinity + +======================================= ================================================================ ================================== + Name Operation Supported element types +======================================= ================================================================ ================================== + T __builtin_elementwise_abs(T x) return the absolute value of a number x integer and floating point types + T __builtin_elementwise_ceil(T x) return the smallest integral value greater than or equal to x floating point types + T __builtin_elementwise_floor(T x) return the largest integral value less than or equal to x floating point types + T __builtin_elementwise_rint(T x) return the integral value nearest to x (according to the floating point types + prevailing rounding mode) in floating-point format + T __builtin_elementwise_round(T x) return the integral value nearest to x rounding half-way cases floating point types + away from zero, regardless of the current rounding direction + T__builtin_elementwise_trunc(T x) return the integral value nearest to but no larger in floating point types + magnitude than x + T __builtin_elementwise_max(T x, T y) return x or y, whichever is larger integer and floating point types + T __builtin_elementwise_min(T x, T y) return x or y, whichever is smaller integer and floating point types +======================================= ================================================================ ================================== + + +*Reduction Builtins* + +Each builtin returns a scalar equivalent to applying the specified +operation(x, y) as pairwise tree reduction to the input. The pairs are formed +by concatenating both inputs and pairing adjacent elements. + +Let ``VT`` be a vector type and ``ET`` the element type of ``VT``. + +======================================= ================================================================ ================================== + Name Operation Supported element types +======================================= ================================================================ ================================== + ET __builtin_reduce_max(VT a) return x or y, whichever is larger; If exactly one argument is integer and floating point types + a NaN, return the other argument. If both arguments are NaNs, + fmax() return a NaN. + ET __builtin_reduce_min(VT a) return x or y, whichever is smaller; If exactly one argument integer and floating point types + is a NaN, return the other argument. If both arguments are + NaNs, fmax() return a NaN. + ET __builtin_reduce_add(VT a) \+ integer and floating point types + ET __builtin_reduce_and(VT a) & integer types + ET __builtin_reduce_or(VT a) \| integer types + ET __builtin_reduce_xor(VT a) ^ integer types +======================================= ================================================================ ================================== + Matrix Types ============