Re: [PATCH] benchtests: Add strtod benchmark

[Adhemerval Zanella <azanella at linux dot vnet dot ibm dot com>]

Thanks for the review Will.


On 05-11-2013 06:33, Will Newton wrote:
>
> Is there a reason why this struct is needed rather than using a const
> char * directly?

Not really, I got the struct by using the source testcase input and never cared
changed. I have changed it now.


>
> I guess there should be a call to TIMING_INIT here. Not sure it is
> essential but it would be consistent at least.

Yeah it is missing and I have added it now.

---

diff --git a/benchtests/Makefile b/benchtests/Makefile
index aec395a..5eb65e5 100644
--- a/benchtests/Makefile
+++ b/benchtests/Makefile
@@ -32,7 +32,9 @@ string-bench := bcopy bzero memccpy memchr memcmp memcpy memmem memmove \
 string-bench-ifunc := $(addsuffix -ifunc, $(string-bench))
 string-bench-all := $(string-bench) $(string-bench-ifunc)
 
-benchset := $(string-bench-all)
+stdlib-bench := strtod
+
+benchset := $(string-bench-all) $(stdlib-bench)
 
 LDLIBS-bench-acos = -lm
 LDLIBS-bench-acosh = -lm
diff --git a/benchtests/bench-strtod.c b/benchtests/bench-strtod.c
new file mode 100644
index 0000000..3a8a65f
--- /dev/null
+++ b/benchtests/bench-strtod.c
@@ -0,0 +1,117 @@
+/* Measure strtod implementation.
+   Copyright (C) 2013 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#define TEST_MAIN
+#define TEST_NAME "strtod"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include "bench-timing.h"
+
+#undef INNER_LOOP_ITERS
+#define INNER_LOOP_ITERS 65536
+
+static const char *inputs[] =
+{
+  "1e308",
+  "100000000e300",
+  "0x1p1023",
+  "0x1000p1011",
+  "0x1p1020",
+  "0x0.00001p1040" "1e-307",
+  "0.000001e-301",
+  "0.0000001e-300",
+  "0.00000001e-299",
+  "1000000e-313",
+  "10000000e-314",
+  "100000000e-315",
+  "0x1p-1021",
+  "0x1000p-1033",
+  "0x10000p-1037",
+  "0x0.001p-1009",
+  "0x0.0001p-1005",
+  "12.345",
+  "12.345e19",
+  "-.1e+9",
+  ".125",
+  "1e20",
+  "0e-19",
+  "4\00012",
+  "5.9e-76",
+  "0x1.4p+3",
+  "0xAp0",
+  "0x0Ap0",
+  "0x0A",
+  "0xA0",
+  "0x0.A0p8",
+  "0x0.50p9",
+  "0x0.28p10",
+  "0x0.14p11",
+  "0x0.0A0p12",
+  "0x0.050p13",
+  "0x0.028p14",
+  "0x0.014p15",
+  "0x00.00A0p16",
+  "0x00.0050p17",
+  "0x00.0028p18",
+  "0x00.0014p19",
+  "0x1p-1023",
+  "0x0.8p-1022",
+  "Inf",
+  "-Inf",
+  "+InFiNiTy",
+  "0x80000Ap-23",
+  "1e-324",
+  "0x100000000000008p0",
+  "0x100000000000008.p0",
+  "0x100000000000008.00p0",
+  "0x10000000000000800p0",
+  "0x10000000000000801p0",
+  NULL
+};
+
+int
+do_bench (void)
+{
+  const size_t iters = INNER_LOOP_ITERS;
+  timing_t res __attribute__ ((unused));
+
+  TIMING_INIT (res);
+
+  for (size_t i = 0; inputs[i] != NULL; ++i)
+    {
+      char *ep;
+      timing_t start, stop, cur;
+
+      printf ("Input %-24s:", inputs[i]);
+      TIMING_NOW (start);
+      for (size_t j = 0; j < iters; ++j)
+	strtod (inputs[i], &ep);
+      TIMING_NOW (stop);
+
+      TIMING_DIFF (cur, start, stop);
+      TIMING_PRINT_MEAN ((double) cur, (double) iters);
+      putchar ('\n');
+    }
+
+  return 0;
+}
+
+#define TEST_FUNCTION do_bench ()
+
+#include "../test-skeleton.c"