[PATCH] benchtests: Add strtod benchmark

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

Hi all,

This patch add a benchtest for 'strtod'. I used as possible input the testing
values from both 'stdlib/tst-strtod.c' and 'stdlib/tst-atof2.c'. I'm aware it
might not be the best inputs that might cover all the strtod cases or even the
user realcases, however adjustment can me made in the future.

---

2013-11-04  Adhemerval Zanella  <azanella@linux.vnet.ibm.com>

	* benchtests/Makefile: Add bench-strtod.
	* benchtests/bench-strtod.c: New file: strtod benchtest.

--

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..72151f9
--- /dev/null
+++ b/benchtests/bench-strtod.c
@@ -0,0 +1,119 @@
+/* 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"
+
+#define INNER_LOOP_ITERS 65536
+
+struct ltest
+  {
+    const char *str;
+  };
+static const struct ltest 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;
+  const struct ltest *lt;
+
+  for (lt = inputs; lt->str != NULL; ++lt)
+    {
+      char *ep;
+      timing_t start, stop, cur;
+
+      printf ("Input %-24s:", lt->str);
+      TIMING_NOW (start);
+      for (size_t i = 0; i < iters; ++i)
+	strtod(lt->str, &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"