[Libclc-dev] [PATCH 1/1] fmod: Port from amd_builtins

Jan Vesely via Libclc-dev libclc-dev at lists.llvm.org
Sun Mar 18 12:16:56 PDT 2018


Uses only denormal path for fp32.
Passes CTS on carrizo and turks.

Signed-off-by: Jan Vesely <jan.vesely at rutgers.edu>
---
 generic/include/clc/math/fmod.h   |   4 +-
 generic/include/clc/math/fmod.inc |   1 -
 generic/include/math/clc_fmod.h   |   4 +
 generic/lib/SOURCES               |   1 +
 generic/lib/math/clc_fmod.cl      | 184 ++++++++++++++++++++++++++++++++++++++
 generic/lib/math/fmod.cl          |  14 +--
 6 files changed, 196 insertions(+), 12 deletions(-)
 delete mode 100644 generic/include/clc/math/fmod.inc
 create mode 100644 generic/include/math/clc_fmod.h
 create mode 100644 generic/lib/math/clc_fmod.cl

diff --git a/generic/include/clc/math/fmod.h b/generic/include/clc/math/fmod.h
index 4906867..443eaf3 100644
--- a/generic/include/clc/math/fmod.h
+++ b/generic/include/clc/math/fmod.h
@@ -1,2 +1,4 @@
-#define __CLC_BODY <clc/math/fmod.inc>
+#define __CLC_FUNCTION fmod
+#define __CLC_BODY <clc/math/binary_decl_tt.inc>
 #include <clc/math/gentype.inc>
+#undef __CLC_FUNCTION
diff --git a/generic/include/clc/math/fmod.inc b/generic/include/clc/math/fmod.inc
deleted file mode 100644
index 39d9153..0000000
--- a/generic/include/clc/math/fmod.inc
+++ /dev/null
@@ -1 +0,0 @@
-_CLC_OVERLOAD _CLC_DECL __CLC_GENTYPE fmod(__CLC_GENTYPE a, __CLC_GENTYPE b);
diff --git a/generic/include/math/clc_fmod.h b/generic/include/math/clc_fmod.h
new file mode 100644
index 0000000..0409785
--- /dev/null
+++ b/generic/include/math/clc_fmod.h
@@ -0,0 +1,4 @@
+#define __CLC_FUNCTION __clc_fmod
+#define __CLC_BODY <clc/math/binary_decl_tt.inc>
+#include <clc/math/gentype.inc>
+#undef __CLC_FUNCTION
diff --git a/generic/lib/SOURCES b/generic/lib/SOURCES
index 843d44d..dfa9d0c 100644
--- a/generic/lib/SOURCES
+++ b/generic/lib/SOURCES
@@ -103,6 +103,7 @@ math/fdim.cl
 math/fma.cl
 math/fmax.cl
 math/fmin.cl
+math/clc_fmod.cl
 math/fmod.cl
 math/fract.cl
 math/frexp.cl
diff --git a/generic/lib/math/clc_fmod.cl b/generic/lib/math/clc_fmod.cl
new file mode 100644
index 0000000..a45c2b4
--- /dev/null
+++ b/generic/lib/math/clc_fmod.cl
@@ -0,0 +1,184 @@
+/*
+ * 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 <clc/clc.h>
+
+#include <math/clc_remainder.h>
+#include "../clcmacro.h"
+#include "config.h"
+#include "math.h"
+
+_CLC_DEF _CLC_OVERLOAD float __clc_fmod(float x, float y)
+{
+    int ux = as_int(x);
+    int ax = ux & EXSIGNBIT_SP32;
+    float xa = as_float(ax);
+    int sx = ux ^ ax;
+    int ex = ax >> EXPSHIFTBITS_SP32;
+
+    int uy = as_int(y);
+    int ay = uy & EXSIGNBIT_SP32;
+    float ya = as_float(ay);
+    int ey = ay >> EXPSHIFTBITS_SP32;
+
+    float xr = as_float(0x3f800000 | (ax & 0x007fffff));
+    float yr = as_float(0x3f800000 | (ay & 0x007fffff));
+    int c;
+    int k = ex - ey;
+
+    while (k > 0) {
+        c = xr >= yr;
+        xr -= c ? yr : 0.0f;
+        xr += xr;
+	--k;
+    }
+
+    c = xr >= yr;
+    xr -= c ? yr : 0.0f;
+
+    int lt = ex < ey;
+
+    xr = lt ? xa : xr;
+    yr = lt ? ya : yr;
+
+
+    float s = as_float(ey << EXPSHIFTBITS_SP32);
+    xr *= lt ? 1.0f : s;
+
+    c = ax == ay;
+    xr = c ? 0.0f : xr;
+
+    xr = as_float(sx ^ as_int(xr));
+
+    c = ax > PINFBITPATT_SP32 | ay > PINFBITPATT_SP32 | ax == PINFBITPATT_SP32 | ay == 0;
+    xr = c ? as_float(QNANBITPATT_SP32) : xr;
+
+    return xr;
+
+}
+_CLC_BINARY_VECTORIZE(_CLC_DEF _CLC_OVERLOAD, float, __clc_fmod, float, float);
+
+#ifdef cl_khr_fp64
+_CLC_DEF _CLC_OVERLOAD double __clc_fmod(double x, double y)
+{
+    ulong ux = as_ulong(x);
+    ulong ax = ux & ~SIGNBIT_DP64;
+    ulong xsgn = ux ^ ax;
+    double dx = as_double(ax);
+    int xexp = convert_int(ax >> EXPSHIFTBITS_DP64);
+    int xexp1 = 11 - (int) clz(ax & MANTBITS_DP64);
+    xexp1 = xexp < 1 ? xexp1 : xexp;
+
+    ulong uy = as_ulong(y);
+    ulong ay = uy & ~SIGNBIT_DP64;
+    double dy = as_double(ay);
+    int yexp = convert_int(ay >> EXPSHIFTBITS_DP64);
+    int yexp1 = 11 - (int) clz(ay & MANTBITS_DP64);
+    yexp1 = yexp < 1 ? yexp1 : yexp;
+
+    // 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 = max(0, (xexp1 - yexp1) / 53);
+    double w =  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 = trunc(dx / w);
+
+        // Compute w * t in quad precision
+        p = w * t;
+        pp = 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 = floor(dx / w);
+    long lt = (long)t;
+    int todd = lt & 1;
+
+    p = w * t;
+    pp = 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)
+    double ret = as_double(xsgn ^ as_ulong(dx));
+    dx = as_double(ax);
+
+    // Now handle |x| == |y|
+    int c = dx == dy;
+    t = as_double(xsgn);
+    ret = c ? t : ret;
+
+    // Next, handle |x| < |y|
+    c = dx < dy;
+    ret = c ? x : ret;
+
+    // We don't need anything special for |x| == 0
+
+    // |y| is 0
+    c = dy == 0.0;
+    ret = c ? 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 ? as_double(QNANBITPATT_DP64) : ret;
+
+    return ret;
+}
+_CLC_BINARY_VECTORIZE(_CLC_DEF _CLC_OVERLOAD, double, __clc_fmod, double, double);
+#endif
diff --git a/generic/lib/math/fmod.cl b/generic/lib/math/fmod.cl
index f9a4e31..fac3fc6 100644
--- a/generic/lib/math/fmod.cl
+++ b/generic/lib/math/fmod.cl
@@ -1,12 +1,6 @@
 #include <clc/clc.h>
-#include "../clcmacro.h"
+#include <math/clc_fmod.h>
 
-_CLC_DEFINE_BINARY_BUILTIN(float, fmod, __builtin_fmodf, float, float)
-
-#ifdef cl_khr_fp64
-
-#pragma OPENCL EXTENSION cl_khr_fp64 : enable
-
-_CLC_DEFINE_BINARY_BUILTIN(double, fmod, __builtin_fmod, double, double)
-
-#endif
+#define __CLC_FUNC fmod
+#define __CLC_BODY <clc_sw_binary.inc>
+#include <clc/math/gentype.inc>
-- 
2.14.3



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