Author: Matt Arsenault Date: 2026-03-23T11:08:13+01:00 New Revision: befad798a91ef8c74f605bdb15c352528f8d9807
URL: https://github.com/llvm/llvm-project/commit/befad798a91ef8c74f605bdb15c352528f8d9807 DIFF: https://github.com/llvm/llvm-project/commit/befad798a91ef8c74f605bdb15c352528f8d9807.diff LOG: libclc: Implement remainder with remquo (#187999) This fixes conformance failures for double and without -cl-denorms-are-zero. Optimizations are able to eliminate the unusued quo handling without duplicating most of the code. Added: libclc/clc/lib/generic/math/clc_remainder.inc Modified: libclc/clc/lib/generic/math/clc_remainder.cl Removed: ################################################################################ diff --git a/libclc/clc/lib/generic/math/clc_remainder.cl b/libclc/clc/lib/generic/math/clc_remainder.cl index f1dba87ee5b43..d3979fbac3ffd 100644 --- a/libclc/clc/lib/generic/math/clc_remainder.cl +++ b/libclc/clc/lib/generic/math/clc_remainder.cl @@ -6,227 +6,8 @@ // //===----------------------------------------------------------------------===// -#include "clc/clc_convert.h" -#include "clc/integer/clc_clz.h" -#include "clc/internal/clc.h" -#include "clc/math/clc_floor.h" -#include "clc/math/clc_fma.h" -#include "clc/math/clc_ldexp.h" #include "clc/math/clc_remainder.h" -#include "clc/math/clc_trunc.h" -#include "clc/math/math.h" -#include "clc/shared/clc_max.h" +#include "clc/math/clc_remquo.h" -_CLC_DEF _CLC_OVERLOAD float __clc_remainder(float x, float y) { - int ux = __clc_as_int(x); - int ax = ux & EXSIGNBIT_SP32; - float xa = __clc_as_float(ax); - int sx = ux ^ ax; - int ex = ax >> EXPSHIFTBITS_SP32; - - int uy = __clc_as_int(y); - int ay = uy & EXSIGNBIT_SP32; - float ya = __clc_as_float(ay); - int ey = ay >> EXPSHIFTBITS_SP32; - - float xr = __clc_as_float(0x3f800000 | (ax & 0x007fffff)); - float yr = __clc_as_float(0x3f800000 | (ay & 0x007fffff)); - int c; - int k = ex - ey; - - uint q = 0; - - while (k > 0) { - c = xr >= yr; - q = (q << 1) | c; - xr -= c ? yr : 0.0f; - xr += xr; - --k; - } - - c = xr > yr; - q = (q << 1) | c; - xr -= c ? yr : 0.0f; - - int lt = ex < ey; - - q = lt ? 0 : q; - xr = lt ? xa : xr; - yr = lt ? ya : yr; - - c = (yr < 2.0f * xr) | ((yr == 2.0f * xr) & ((q & 0x1) == 0x1)); - xr -= c ? yr : 0.0f; - q += c; - - float s = __clc_as_float(ey << EXPSHIFTBITS_SP32); - xr *= lt ? 1.0f : s; - - c = ax == ay; - xr = c ? 0.0f : xr; - - xr = __clc_as_float(sx ^ __clc_as_int(xr)); - - c = ax > PINFBITPATT_SP32 | ay > PINFBITPATT_SP32 | ax == PINFBITPATT_SP32 | - ay == 0; - xr = c ? __clc_as_float(QNANBITPATT_SP32) : xr; - - return xr; -} - -#define __CLC_FLOAT_ONLY -#define __CLC_FUNCTION __clc_remainder -#define __CLC_BODY "clc/shared/binary_def_scalarize.inc" +#define __CLC_BODY "clc_remainder.inc" #include "clc/math/gentype.inc" -#undef __CLC_FUNCTION - -#ifdef cl_khr_fp64 - -#pragma OPENCL EXTENSION cl_khr_fp64 : enable - -_CLC_DEF _CLC_OVERLOAD double __clc_remainder(double x, double y) { - ulong ux = __clc_as_ulong(x); - ulong ax = ux & ~SIGNBIT_DP64; - ulong xsgn = ux ^ ax; - double dx = __clc_as_double(ax); - int xexp = __clc_convert_int(ax >> EXPSHIFTBITS_DP64); - int xexp1 = 11 - (int)__clc_clz(ax & MANTBITS_DP64); - xexp1 = xexp < 1 ? xexp1 : xexp; - - ulong uy = __clc_as_ulong(y); - ulong ay = uy & ~SIGNBIT_DP64; - double dy = __clc_as_double(ay); - int yexp = __clc_convert_int(ay >> EXPSHIFTBITS_DP64); - int yexp1 = 11 - (int)__clc_clz(ay & MANTBITS_DP64); - yexp1 = yexp < 1 ? yexp1 : yexp; - - int qsgn = ((ux ^ uy) & SIGNBIT_DP64) == 0UL ? 1 : -1; - - // First assume |x| > |y| - - // Set ntimes to the number of times we need to do a - // partial remainder. If the exponent of x is an exact multiple - // of 53 larger than the exponent of y, and the mantissa of x is - // less than the mantissa of y, ntimes will be one too large - // but it doesn't matter - it just means that we'll go round - // the loop below one extra time. - int ntimes = __clc_max(0, (xexp1 - yexp1) / 53); - double w = __clc_ldexp(dy, ntimes * 53); - w = ntimes == 0 ? dy : w; - double scale = ntimes == 0 ? 1.0 : 0x1.0p-53; - - // Each time round the loop we compute a partial remainder. - // This is done by subtracting a large multiple of w - // from x each time, where w is a scaled up version of y. - // The subtraction must be performed exactly in quad - // precision, though the result at each stage can - // fit exactly in a double precision number. - int i; - double t, v, p, pp; - - for (i = 0; i < ntimes; i++) { - // Compute integral multiplier - t = __clc_trunc(dx / w); - - // Compute w * t in quad precision - p = w * t; - pp = __clc_fma(w, t, -p); - - // Subtract w * t from dx - v = dx - p; - dx = v + (((dx - v) - p) - pp); - - // If t was one too large, dx will be negative. Add back one w. - dx += dx < 0.0 ? w : 0.0; - - // Scale w down by 2^(-53) for the next iteration - w *= scale; - } - - // One more time - // Variable todd says whether the integer t is odd or not - t = __clc_floor(dx / w); - long lt = (long)t; - int todd = lt & 1; - - p = w * t; - pp = __clc_fma(w, t, -p); - v = dx - p; - dx = v + (((dx - v) - p) - pp); - i = dx < 0.0; - todd ^= i; - dx += i ? w : 0.0; - - // At this point, dx lies in the range [0,dy) - - // For the fmod function, we're done apart from setting the correct sign. - // - // For the remainder function, we need to adjust dx - // so that it lies in the range (-y/2, y/2] by carefully - // subtracting w (== dy == y) if necessary. The rigmarole - // with todd is to get the correct sign of the result - // when x/y lies exactly half way between two integers, - // when we need to choose the even integer. - - int al = (2.0 * dx > w) | (todd & (2.0 * dx == w)); - double dxl = dx - (al ? w : 0.0); - - int ag = (dx > 0.5 * w) | (todd & (dx == 0.5 * w)); - double dxg = dx - (ag ? w : 0.0); - - dx = dy < 0x1.0p+1022 ? dxl : dxg; - - double ret = __clc_as_double(xsgn ^ __clc_as_ulong(dx)); - dx = __clc_as_double(ax); - - // Now handle |x| == |y| - int c = dx == dy; - t = __clc_as_double(xsgn); - ret = c ? t : ret; - - // Next, handle |x| < |y| - c = dx < dy; - ret = c ? x : ret; - - c &= (yexp<1023 & 2.0 * dx> dy) | (dx > 0.5 * dy); - // we could use a conversion here instead since qsgn = +-1 - p = qsgn == 1 ? -1.0 : 1.0; - t = __clc_fma(y, p, x); - ret = c ? t : ret; - - // We don't need anything special for |x| == 0 - - // |y| is 0 - c = dy == 0.0; - ret = c ? __clc_as_double(QNANBITPATT_DP64) : ret; - - // y is +-Inf, NaN - c = yexp > BIASEDEMAX_DP64; - t = y == y ? x : y; - ret = c ? t : ret; - - // x is +=Inf, NaN - c = xexp > BIASEDEMAX_DP64; - ret = c ? __clc_as_double(QNANBITPATT_DP64) : ret; - - return ret; -} - -#define __CLC_DOUBLE_ONLY -#define __CLC_FUNCTION __clc_remainder -#define __CLC_BODY "clc/shared/binary_def_scalarize.inc" -#include "clc/math/gentype.inc" -#undef __CLC_FUNCTION - -#endif - -#ifdef cl_khr_fp16 - -#pragma OPENCL EXTENSION cl_khr_fp16 : enable - -// Forward the half version of this builtin onto the float one -#define __CLC_HALF_ONLY -#define __CLC_FUNCTION __clc_remainder -#define __CLC_BODY "clc/math/binary_def_via_fp32.inc" -#include "clc/math/gentype.inc" - -#endif diff --git a/libclc/clc/lib/generic/math/clc_remainder.inc b/libclc/clc/lib/generic/math/clc_remainder.inc new file mode 100644 index 0000000000000..9f2e0ba1539a6 --- /dev/null +++ b/libclc/clc/lib/generic/math/clc_remainder.inc @@ -0,0 +1,13 @@ +//===----------------------------------------------------------------------===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// + +_CLC_DEF _CLC_OVERLOAD _CLC_CONST __CLC_GENTYPE +__clc_remainder(__CLC_GENTYPE x, __CLC_GENTYPE y) { + __CLC_INTN unused_quo; + return __clc_remquo(x, y, &unused_quo); +} _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
