diff --git a/libclc/generic/include/clc/math/fma.h b/libclc/generic/include/clc/math/fma.h index 02d39f681675..c7c23eb2055f 100644 --- a/libclc/generic/include/clc/math/fma.h +++ b/libclc/generic/include/clc/math/fma.h @@ -1,6 +1,7 @@ -#undef fma -#define fma __clc_fma +#define __CLC_BODY +#define __CLC_FUNCTION fma -#define __CLC_FUNCTION __clc_fma -#define __CLC_INTRINSIC "llvm.fma" -#include +#include + +#undef __CLC_BODY +#undef __CLC_FUNCTION diff --git a/libclc/generic/include/clc/math/ternary_decl.inc b/libclc/generic/include/clc/math/ternary_decl.inc new file mode 100644 index 000000000000..0598684ea406 --- /dev/null +++ b/libclc/generic/include/clc/math/ternary_decl.inc @@ -0,0 +1 @@ +_CLC_OVERLOAD _CLC_DECL __CLC_GENTYPE __CLC_FUNCTION(__CLC_GENTYPE a, __CLC_GENTYPE b, __CLC_GENTYPE c); diff --git a/libclc/generic/include/math/clc_fma.h b/libclc/generic/include/math/clc_fma.h new file mode 100644 index 000000000000..3ae6a744b052 --- /dev/null +++ b/libclc/generic/include/math/clc_fma.h @@ -0,0 +1,11 @@ +#define __CLC_FUNCTION __clc_fma +#define __CLC_INTRINSIC "llvm.fma" +#include + +#define __FLOAT_ONLY +#define __CLC_FUNCTION __clc_sw_fma +#define __CLC_BODY +#include +#undef __CLC_BODY +#undef __CLC_FUNCTION +#undef __FLOAT_ONLY diff --git a/libclc/generic/lib/SOURCES b/libclc/generic/lib/SOURCES index 1f1a427adfd7..565750e08c8a 100644 --- a/libclc/generic/lib/SOURCES +++ b/libclc/generic/lib/SOURCES @@ -101,6 +101,8 @@ math/exp2.cl math/clc_exp10.cl math/exp10.cl math/fdim.cl +math/clc_fma.cl +math/fma.cl math/fmax.cl math/fmin.cl math/clc_fmod.cl diff --git a/libclc/generic/lib/math/clc_fma.cl b/libclc/generic/lib/math/clc_fma.cl new file mode 100644 index 000000000000..dee90e999c39 --- /dev/null +++ b/libclc/generic/lib/math/clc_fma.cl @@ -0,0 +1,158 @@ +/* + * Copyright (c) 2014 Advanced Micro Devices, Inc. + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ + +#include + +#include "config.h" +#include "math.h" +#include "../clcmacro.h" + +struct fp { + ulong mantissa; + int exponent; + uint sign; +}; + +_CLC_DEF _CLC_OVERLOAD float __clc_sw_fma(float a, float b, float c) +{ + /* special cases */ + if (isnan(a) || isnan(b) || isnan(c) || isinf(a) || isinf(b)) + return mad(a, b, c); + + /* If only c is inf, and both a,b are regular numbers, the result is c*/ + if (isinf(c)) + return c; + + a = __clc_flush_denormal_if_not_supported(a); + b = __clc_flush_denormal_if_not_supported(b); + c = __clc_flush_denormal_if_not_supported(c); + + if (c == 0) + return a * b; + + struct fp st_a, st_b, st_c; + + st_a.exponent = a == .0f ? 0 : ((as_uint(a) & 0x7f800000) >> 23) - 127; + st_b.exponent = b == .0f ? 0 : ((as_uint(b) & 0x7f800000) >> 23) - 127; + st_c.exponent = c == .0f ? 0 : ((as_uint(c) & 0x7f800000) >> 23) - 127; + + st_a.mantissa = a == .0f ? 0 : (as_uint(a) & 0x7fffff) | 0x800000; + st_b.mantissa = b == .0f ? 0 : (as_uint(b) & 0x7fffff) | 0x800000; + st_c.mantissa = c == .0f ? 0 : (as_uint(c) & 0x7fffff) | 0x800000; + + st_a.sign = as_uint(a) & 0x80000000; + st_b.sign = as_uint(b) & 0x80000000; + st_c.sign = as_uint(c) & 0x80000000; + + // Multiplication. + // Move the product to the highest bits to maximize precision + // mantissa is 24 bits => product is 48 bits, 2bits non-fraction. + // Add one bit for future addition overflow, + // add another bit to detect subtraction underflow + struct fp st_mul; + st_mul.sign = st_a.sign ^ st_b.sign; + st_mul.mantissa = (st_a.mantissa * st_b.mantissa) << 14ul; + st_mul.exponent = st_mul.mantissa ? st_a.exponent + st_b.exponent : 0; + + // FIXME: Detecting a == 0 || b == 0 above crashed GCN isel + if (st_mul.exponent == 0 && st_mul.mantissa == 0) + return c; + +// Mantissa is 23 fractional bits, shift it the same way as product mantissa +#define C_ADJUST 37ul + + // both exponents are bias adjusted + int exp_diff = st_mul.exponent - st_c.exponent; + + st_c.mantissa <<= C_ADJUST; + ulong cutoff_bits = 0; + ulong cutoff_mask = (1ul << abs(exp_diff)) - 1ul; + if (exp_diff > 0) { + cutoff_bits = exp_diff >= 64 ? st_c.mantissa : (st_c.mantissa & cutoff_mask); + st_c.mantissa = exp_diff >= 64 ? 0 : (st_c.mantissa >> exp_diff); + } else { + cutoff_bits = -exp_diff >= 64 ? st_mul.mantissa : (st_mul.mantissa & cutoff_mask); + st_mul.mantissa = -exp_diff >= 64 ? 0 : (st_mul.mantissa >> -exp_diff); + } + + struct fp st_fma; + st_fma.sign = st_mul.sign; + st_fma.exponent = max(st_mul.exponent, st_c.exponent); + if (st_c.sign == st_mul.sign) { + st_fma.mantissa = st_mul.mantissa + st_c.mantissa; + } else { + // cutoff bits borrow one + st_fma.mantissa = st_mul.mantissa - st_c.mantissa - (cutoff_bits && (st_mul.exponent > st_c.exponent) ? 1 : 0); + } + + // underflow: st_c.sign != st_mul.sign, and magnitude switches the sign + if (st_fma.mantissa > LONG_MAX) { + st_fma.mantissa = 0 - st_fma.mantissa; + st_fma.sign = st_mul.sign ^ 0x80000000; + } + + // detect overflow/underflow + int overflow_bits = 3 - clz(st_fma.mantissa); + + // adjust exponent + st_fma.exponent += overflow_bits; + + // handle underflow + if (overflow_bits < 0) { + st_fma.mantissa <<= -overflow_bits; + overflow_bits = 0; + } + + // rounding + ulong trunc_mask = (1ul << (C_ADJUST + overflow_bits)) - 1; + ulong trunc_bits = (st_fma.mantissa & trunc_mask) | (cutoff_bits != 0); + ulong last_bit = st_fma.mantissa & (1ul << (C_ADJUST + overflow_bits)); + ulong grs_bits = (0x4ul << (C_ADJUST - 3 + overflow_bits)); + + // round to nearest even + if ((trunc_bits > grs_bits) || + (trunc_bits == grs_bits && last_bit != 0)) + st_fma.mantissa += (1ul << (C_ADJUST + overflow_bits)); + + // Shift mantissa back to bit 23 + st_fma.mantissa = (st_fma.mantissa >> (C_ADJUST + overflow_bits)); + + // Detect rounding overflow + if (st_fma.mantissa > 0xffffff) { + ++st_fma.exponent; + st_fma.mantissa >>= 1; + } + + if (st_fma.mantissa == 0) + return .0f; + + // Flating point range limit + if (st_fma.exponent > 127) + return as_float(as_uint(INFINITY) | st_fma.sign); + + // Flush denormals + if (st_fma.exponent <= -127) + return as_float(st_fma.sign); + + return as_float(st_fma.sign | ((st_fma.exponent + 127) << 23) | ((uint)st_fma.mantissa & 0x7fffff)); +} +_CLC_TERNARY_VECTORIZE(_CLC_DEF _CLC_OVERLOAD, float, __clc_sw_fma, float, float, float) diff --git a/libclc/generic/lib/math/fma.cl b/libclc/generic/lib/math/fma.cl new file mode 100644 index 000000000000..9ad81be696d9 --- /dev/null +++ b/libclc/generic/lib/math/fma.cl @@ -0,0 +1,7 @@ +#include + +#include "math.h" +#include "math/clc_fma.h" + +#define __CLC_BODY +#include diff --git a/libclc/generic/lib/math/fma.inc b/libclc/generic/lib/math/fma.inc new file mode 100644 index 000000000000..654208fac21a --- /dev/null +++ b/libclc/generic/lib/math/fma.inc @@ -0,0 +1,7 @@ +_CLC_DEF _CLC_OVERLOAD __CLC_GENTYPE fma(__CLC_GENTYPE a, __CLC_GENTYPE b, __CLC_GENTYPE c) { +#if __CLC_FPSIZE == 32 && HAVE_HW_FMA32() == 0 + return __clc_sw_fma(a, b, c); +#else + return __clc_fma(a, b, c); +#endif +}