diff --git a/docs/ispc.rst b/docs/ispc.rst index 94cfa600..3fd31978 100644 --- a/docs/ispc.rst +++ b/docs/ispc.rst @@ -3615,6 +3615,39 @@ normalized exponent as a power of two in the ``pw2`` parameter. uniform int * uniform pw2) +Saturating Arithmetic +--------------------- +A saturation (no overflow possible) addition, substraction, multiplication and +division of all integer types is provided by the ``ispc`` standard library. + +:: + + int8 saturating_add(uniform int8 a, uniform int8 b) + int8 saturating_add(varying int8 a, varying int8 b) + unsigned int8 saturating_add(uniform unsigned int8 a, uniform unsigned int8 b) + unsigned int8 saturating_add(varying unsigned int8 a, varying unsigned int8 b) + + int8 saturating_sub(uniform int8 a, uniform int8 b) + int8 saturating_sub(varying int8 a, varying int8 b) + unsigned int8 saturating_sub(uniform unsigned int8 a, uniform unsigned int8 b) + unsigned int8 saturating_sub(varying unsigned int8 a, varying unsigned int8 b) + + int8 saturating_mul(uniform int8 a, uniform int8 b) + int8 saturating_mul(varying int8 a, varying int8 b) + unsigned int8 saturating_mul(uniform unsigned int8 a, uniform unsigned int8 b) + unsigned int8 saturating_mul(varying unsigned int8 a, varying unsigned int8 b) + + int8 saturating_div(uniform int8 a, uniform int8 b) + int8 saturating_div(varying int8 a, varying int8 b) + unsigned int8 saturating_div(uniform unsigned int8 a, uniform unsigned int8 b) + unsigned int8 saturating_div(varying unsigned int8 a,varying unsigned int8 b) + + +In addition to the ``int8`` variants of saturating arithmetic functions listed +above, there are versions that supports ``int16``, ``int32`` and ``int64`` +values as well. + + Pseudo-Random Numbers --------------------- diff --git a/stdlib.ispc b/stdlib.ispc index 1582a04a..a2ca02e7 100644 --- a/stdlib.ispc +++ b/stdlib.ispc @@ -4938,6 +4938,150 @@ static inline varying unsigned int32 saturating_mul(varying unsigned int32 a, varying unsigned int32 lo = result; return lo | - (varying int32) !! hi; } + +static inline uniform int64 saturating_mul(uniform int64 a, uniform int64 b) { + uniform unsigned int64 ret = 0; + + uniform int8 sign = (((a > 0) && (b > 0)) || ((a < 0) && (b < 0))) ? 1 : -1; + uniform unsigned int64 a_abs = 0; + uniform unsigned int64 b_abs = 0; + + if (a == INT64_MIN) + a_abs = (uniform unsigned int64) INT64_MIN; + // Operation "-" is undefined for "INT64_MIN". + //See 6.3.1.3 section in C99 standart. + else + a_abs = (a > 0) ? a : -a; + + if (b == INT64_MIN) + b_abs = (uniform unsigned int64) INT64_MIN; + else + b_abs = (b > 0) ? b : -b; + + uniform unsigned int32 a0 = a_abs & 0xFFFFFFFF; + uniform unsigned int32 b0 = b_abs & 0xFFFFFFFF; + uniform unsigned int32 a1 = a_abs >> 32; + uniform unsigned int32 b1 = b_abs >> 32; + + if ((a1 != 0) && (b1 != 0)) { + if (sign > 0) { + return INT64_MAX; + } + else { + return INT64_MIN; + } + } else if (a1 != 0) { + ret = saturating_add ((uniform unsigned int64) saturating_mul (b0, a1) << 32 , + (uniform unsigned int64) (a0) * b0); + } else if (b1 != 0) { + ret = saturating_add ((uniform unsigned int64) saturating_mul (a0, b1) << 32 , + (uniform unsigned int64) (a0) * b0); + } else { + ret = a_abs * b_abs; + } + + + if ((sign < 0) && (ret >= (uniform unsigned int64) INT64_MIN)) { + return INT64_MIN; + } else if ((sign > 0) && (ret >= INT64_MAX)) { + return INT64_MAX; + } else { + return ret * sign; + } +} + +static inline varying int64 saturating_mul(varying int64 a, varying int64 b) { + varying unsigned int64 ret = 0; + + varying int8 sign = (((a > 0) && (b > 0)) || ((a < 0) && (b < 0))) ? 1 : -1; + varying unsigned int64 a_abs = 0; + varying unsigned int64 b_abs = 0; + + if (a == INT64_MIN) + a_abs = (varying unsigned int64) INT64_MIN; + // Operation "-" is undefined for "INT64_MIN". + //See 6.3.1.3 section in C99 standart. + else + a_abs = (a > 0) ? a : -a; + + if (b == INT64_MIN) + b_abs = (varying unsigned int64) INT64_MIN; + else + b_abs = (b > 0) ? b : -b; + + + varying unsigned int32 a0 = a_abs & 0xFFFFFFFF; + varying unsigned int32 b0 = b_abs & 0xFFFFFFFF; + varying unsigned int32 a1 = a_abs >> 32; + varying unsigned int32 b1 = b_abs >> 32; + + if ((a1 != 0) && (b1 != 0)) { + if (sign > 0) { + return INT64_MAX; + } + else { + return INT64_MIN; + } + } else if (a1 != 0) { + ret = saturating_add ((varying unsigned int64) saturating_mul (b0, a1) << 32 , + (varying unsigned int64) (a0) * b0); + } else if (b1 != 0) { + ret = saturating_add ((varying unsigned int64) saturating_mul (a0, b1) << 32 , + (varying unsigned int64) (a0) * b0); + } else { + ret = a_abs * b_abs; + } + + + if ((sign < 0) && (ret >= (varying unsigned int64) INT64_MIN)) { + return INT64_MIN; + } else if ((sign > 0) && (ret >= INT64_MAX)) { + return INT64_MAX; + } else { + return ret * sign; + } +} + + +static inline uniform unsigned int64 saturating_mul(uniform unsigned int64 a, + uniform unsigned int64 b) { + uniform unsigned int32 a0 = a & 0xFFFFFFFF; + uniform unsigned int32 b0 = b & 0xFFFFFFFF; + uniform unsigned int32 a1 = a >> 32; + uniform unsigned int32 b1 = b >> 32; + + if ((a1 != 0) && (b1 != 0)) { + return UINT64_MAX; + } else if (a1 != 0) { + return saturating_add ((uniform unsigned int64) saturating_mul (b0, a1) << 32 , + (uniform unsigned int64) (a0) * b0); + } else if (b1 != 0) { + return saturating_add ((uniform unsigned int64) saturating_mul (a0, b1) << 32 , + (uniform unsigned int64) (a0) * b0); + } else { + return a * b; + } +} + +static inline varying unsigned int64 saturating_mul(varying unsigned int64 a, + varying unsigned int64 b) { + varying unsigned int32 a0 = a & 0xFFFFFFFF; + varying unsigned int32 b0 = b & 0xFFFFFFFF; + varying unsigned int32 a1 = a >> 32; + varying unsigned int32 b1 = b >> 32; + + if ((a1 != 0) && (b1 != 0)) { + return UINT64_MAX; + } else if (a1 != 0) { + return saturating_add ((varying unsigned int64) saturating_mul (b0, a1) << 32 , + (varying unsigned int64) (a0) * b0); + } else if (b1 != 0) { + return saturating_add ((varying unsigned int64) saturating_mul (a0, b1) << 32 , + (varying unsigned int64) (a0) * b0); + } else { + return a * b; + } +} /////////////////////////////////////////////////////////////////////////// // rdrand diff --git a/tests/pmuls_i64.ispc b/tests/pmuls_i64.ispc new file mode 100644 index 00000000..a04ca698 --- /dev/null +++ b/tests/pmuls_i64.ispc @@ -0,0 +1,28 @@ + +export uniform int width() { return programCount; } + +export void f_fu(uniform float RET[], uniform float aFOO[], uniform float b) { + uniform int64 a_max = 0x7FFFFFFFFFFFFFFF, a_min = -0x8000000000000000; // max and min signed int64 + if (programIndex % 3 == 0) { + RET[programIndex] = saturating_mul(a_max, (uniform int64) b); + } + else if (programIndex % 3 == 1) { + RET[programIndex] = saturating_mul(a_min, (uniform int64) b); + } + else { + RET[programIndex] = saturating_mul((uniform int64) b, + (uniform int64) b); + } +} + +export void result(uniform float RET[]) { + if (programIndex % 3 == 0) { + RET[programIndex] = (uniform int64) 0x7FFFFFFFFFFFFFFF; // max signed int64 + } + else if (programIndex % 3 == 1) { + RET[programIndex] = (uniform int64) -0x8000000000000000; // min signed int64 + } + else { + RET[programIndex] = (uniform int64) 25; + } +} diff --git a/tests/pmuls_vi64.ispc b/tests/pmuls_vi64.ispc new file mode 100644 index 00000000..32df2fac --- /dev/null +++ b/tests/pmuls_vi64.ispc @@ -0,0 +1,28 @@ + +export uniform int width() { return programCount; } + +export void f_fu(uniform float RET[], uniform float aFOO[], uniform float b) { + varying int64 a_max = 0x7FFFFFFFFFFFFFFF, a_min = -0x8000000000000000; // max and min signed int64 + if (programIndex % 3 == 0) { + RET[programIndex] = saturating_mul(a_max, (varying int64) b); + } + else if (programIndex % 3 == 1) { + RET[programIndex] = saturating_mul(a_min, (varying int64) b); + } + else { + RET[programIndex] = saturating_mul((varying int64) b, + (varying int64) b); + } +} + +export void result(uniform float RET[]) { + if (programIndex % 3 == 0) { + RET[programIndex] = (varying int64) 0x7FFFFFFFFFFFFFFF; // max signed int64 + } + else if (programIndex % 3 == 1) { + RET[programIndex] = (varying int64) -0x8000000000000000; // min signed int64 + } + else { + RET[programIndex] = (varying int64) 25; + } +} diff --git a/tests/pmulus_i64.ispc b/tests/pmulus_i64.ispc new file mode 100644 index 00000000..179902a3 --- /dev/null +++ b/tests/pmulus_i64.ispc @@ -0,0 +1,28 @@ + +export uniform int width() { return programCount; } + +export void f_fu(uniform float RET[], uniform float aFOO[], uniform float b) { + uniform unsigned int64 a_max = 0xFFFFFFFFFFFFFFFF, a_min = 0; // max and min unsigned int64 + if (programIndex % 3 == 0) { + RET[programIndex] = saturating_mul(a_max, (uniform unsigned int64) b); + } + else if (programIndex % 3 == 1) { + RET[programIndex] = saturating_mul(a_min, (uniform unsigned int64) -b); + } + else { + RET[programIndex] = saturating_mul((uniform unsigned int64) b, + (uniform unsigned int64) b); + } +} + +export void result(uniform float RET[]) { + if (programIndex % 3 == 0) { + RET[programIndex] = (uniform unsigned int64) 0xFFFFFFFFFFFFFFFF; // max unsigned int64 + } + else if (programIndex % 3 == 1) { + RET[programIndex] = (uniform unsigned int64) 0; // min unsigned int64 + } + else { + RET[programIndex] = (uniform unsigned int64) 25; + } +} diff --git a/tests/pmulus_vi64.ispc b/tests/pmulus_vi64.ispc new file mode 100644 index 00000000..43ae9aac --- /dev/null +++ b/tests/pmulus_vi64.ispc @@ -0,0 +1,28 @@ + +export uniform int width() { return programCount; } + +export void f_fu(uniform float RET[], uniform float aFOO[], uniform float b) { + varying unsigned int64 a_max = 0xFFFFFFFFFFFFFFFF, a_min = 0; // max and min unsigned int64 + if (programIndex % 3 == 0) { + RET[programIndex] = saturating_mul(a_max, (varying unsigned int64) b); + } + else if (programIndex % 3 == 1) { + RET[programIndex] = saturating_mul(a_min, (varying unsigned int64) -b); + } + else { + RET[programIndex] = saturating_mul((varying unsigned int64) b, + (varying unsigned int64) b); + } +} + +export void result(uniform float RET[]) { + if (programIndex % 3 == 0) { + RET[programIndex] = (varying unsigned int64) 0xFFFFFFFFFFFFFFFF; // max unsigned int64 + } + else if (programIndex % 3 == 1) { + RET[programIndex] = (varying unsigned int64) 0; // min unsigned int64 + } + else { + RET[programIndex] = (varying unsigned int64) 25; + } +}