[glibc] benchtests: Improve bench-strrchr

[glibc] benchtests: Improve bench-strrchr

[Noah Goldstein]

https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=c2ff9555a18b84732004d061b1a797ea1a432c6a

commit c2ff9555a18b84732004d061b1a797ea1a432c6a
Author: Noah Goldstein <goldstein.w.n@gmail.com>
Date:   Fri Apr 22 14:11:59 2022 -0500

    benchtests: Improve bench-strrchr
    
    1. Use json-lib for printing results.
    2. Expose all parameters (before pos, seek_char, and max_char where
       not printed).
    3. Add benchmarks that test multiple occurence of seek_char in the
       string.
    Reviewed-by: H.J. Lu <hjl.tools@gmail.com>

Diff:
---
 benchtests/bench-strrchr.c | 126 +++++++++++++++++++++++++++++----------------
 1 file changed, 82 insertions(+), 44 deletions(-)

diff --git a/benchtests/bench-strrchr.c b/benchtests/bench-strrchr.c
index abdae60c51..7cd2a15484 100644
--- a/benchtests/bench-strrchr.c
+++ b/benchtests/bench-strrchr.c
@@ -23,6 +23,7 @@
 # define TEST_NAME "strrchr"
 #endif
 #include "bench-string.h"
+#include "json-lib.h"
 
 #define BIG_CHAR MAX_CHAR
 
@@ -53,7 +54,8 @@ SIMPLE_STRRCHR (const CHAR *s, int c)
 }
 
 static void
-do_one_test (impl_t *impl, const CHAR *s, int c, CHAR *exp_res)
+do_one_test (json_ctx_t *json_ctx, impl_t *impl, const CHAR *s, int c,
+	     CHAR *exp_res)
 {
   CHAR *res = CALL (impl, s, c);
   size_t i, iters = INNER_LOOP_ITERS8;
@@ -61,8 +63,8 @@ do_one_test (impl_t *impl, const CHAR *s, int c, CHAR *exp_res)
 
   if (res != exp_res)
     {
-      error (0, 0, "Wrong result in function %s %p %p", impl->name,
-	     res, exp_res);
+      error (0, 0, "Wrong result in function %s %p %p", impl->name, res,
+	     exp_res);
       ret = 1;
       return;
     }
@@ -73,23 +75,25 @@ do_one_test (impl_t *impl, const CHAR *s, int c, CHAR *exp_res)
       CALL (impl, s, c);
     }
   TIMING_NOW (stop);
-
   TIMING_DIFF (cur, start, stop);
 
-  TIMING_PRINT_MEAN ((double) cur, (double) iters);
+  json_element_double (json_ctx, (double) cur / (double) iters);
 }
 
 static void
-do_test (size_t align, size_t pos, size_t len, int seek_char, int max_char)
+do_test (json_ctx_t *json_ctx, size_t align, size_t pos, size_t len,
+	 int seek_char, int max_char, size_t freq)
 /* For wcsrchr: align here means align not in bytes,
    but in wchar_ts, in bytes it will equal to align * (sizeof (wchar_t))
    len for wcschr here isn't in bytes but it's number of wchar_t symbols.  */
 {
   size_t i;
+  size_t pos_chunk_sz = freq ? (pos / freq) : pos;
+  size_t last_pos = len;
   CHAR *result;
   CHAR *buf = (CHAR *) buf1;
 
-  align &= 7;
+  align &= (getpagesize () - 1);
   if ((align + len) * sizeof (CHAR) >= page_size)
     return;
 
@@ -103,6 +107,16 @@ do_test (size_t align, size_t pos, size_t len, int seek_char, int max_char)
       if ((i > pos || pos >= len) && buf[align + i] == seek_char)
 	buf[align + i] = seek_char + 10 + (random () & 15);
     }
+
+  if (pos_chunk_sz == 0 && pos)
+    pos_chunk_sz = 1;
+
+  for (i = pos_chunk_sz; i < pos && i < len; i += pos_chunk_sz)
+    {
+      buf[align + i] = seek_char;
+      last_pos = i;
+    }
+
   buf[align + len] = 0;
 
   if (pos < len)
@@ -110,66 +124,90 @@ do_test (size_t align, size_t pos, size_t len, int seek_char, int max_char)
       buf[align + pos] = seek_char;
       result = (CHAR *) (buf + align + pos);
     }
+  else if (last_pos < len)
+    result = (CHAR *) (buf + align + last_pos);
   else if (seek_char == 0)
     result = (CHAR *) (buf + align + len);
   else
     result = NULL;
 
-  printf ("Length %4zd, alignment in bytes %2zd:", len, align * sizeof (CHAR));
+  json_element_object_begin (json_ctx);
+  json_attr_uint (json_ctx, "len", len);
+  json_attr_uint (json_ctx, "pos", pos);
+  json_attr_uint (json_ctx, "align", align);
+  json_attr_uint (json_ctx, "freq", freq);
+  json_attr_uint (json_ctx, "seek", seek_char);
+  json_attr_uint (json_ctx, "max_char", max_char);
+  json_array_begin (json_ctx, "timings");
 
   FOR_EACH_IMPL (impl, 0)
-    do_one_test (impl, (CHAR *) (buf + align), seek_char, result);
+    do_one_test (json_ctx, impl, (CHAR *) (buf + align), seek_char, result);
 
-  putchar ('\n');
+  json_array_end (json_ctx);
+  json_element_object_end (json_ctx);
 }
 
 int
 test_main (void)
 {
-  size_t i;
+  json_ctx_t json_ctx;
+  size_t i, j;
+  int seek;
 
   test_init ();
+  json_init (&json_ctx, 0, stdout);
 
-  printf ("%20s", "");
-  FOR_EACH_IMPL (impl, 0)
-    printf ("\t%s", impl->name);
-  putchar ('\n');
-
-  for (i = 1; i < 8; ++i)
-    {
-      do_test (0, 16 << i, 2048, 23, SMALL_CHAR);
-      do_test (i, 16 << i, 2048, 23, SMALL_CHAR);
-    }
+  json_document_begin (&json_ctx);
+  json_attr_string (&json_ctx, "timing_type", TIMING_TYPE);
 
-  for (i = 1; i < 8; ++i)
-    {
-      do_test (i, 64, 256, 23, SMALL_CHAR);
-      do_test (i, 64, 256, 23, BIG_CHAR);
-    }
+  json_attr_object_begin (&json_ctx, "functions");
+  json_attr_object_begin (&json_ctx, TEST_NAME);
+  json_attr_string (&json_ctx, "bench-variant", "");
 
-  for (i = 0; i < 32; ++i)
-    {
-      do_test (0, i, i + 1, 23, SMALL_CHAR);
-      do_test (0, i, i + 1, 23, BIG_CHAR);
-    }
+  json_array_begin (&json_ctx, "ifuncs");
+  FOR_EACH_IMPL (impl, 0)
+    json_element_string (&json_ctx, impl->name);
+  json_array_end (&json_ctx);
 
-  for (i = 1; i < 8; ++i)
-    {
-      do_test (0, 16 << i, 2048, 0, SMALL_CHAR);
-      do_test (i, 16 << i, 2048, 0, SMALL_CHAR);
-    }
+  json_array_begin (&json_ctx, "results");
 
-  for (i = 1; i < 8; ++i)
+  for (seek = 0; seek <= 23; seek += 23)
     {
-      do_test (i, 64, 256, 0, SMALL_CHAR);
-      do_test (i, 64, 256, 0, BIG_CHAR);
+      for (j = 1; j < 32; j += j)
+	{
+	  for (i = 1; i < 9; ++i)
+	    {
+	      do_test (&json_ctx, 0, 16 << i, 2048, seek, SMALL_CHAR, j);
+	      do_test (&json_ctx, i, 16 << i, 2048, seek, SMALL_CHAR, j);
+	    }
+
+	  for (i = 1; i < 8; ++i)
+	    {
+	      do_test (&json_ctx, i, 64, 256, seek, SMALL_CHAR, j);
+	      do_test (&json_ctx, i, 64, 256, seek, BIG_CHAR, j);
+
+	      do_test (&json_ctx, i * 15, 64, 256, seek, SMALL_CHAR, j);
+	      do_test (&json_ctx, i * 15, 64, 256, seek, BIG_CHAR, j);
+	    }
+
+	  for (i = 0; i < 32; ++i)
+	    {
+	      do_test (&json_ctx, 0, i, i + 1, seek, SMALL_CHAR, j);
+	      do_test (&json_ctx, 0, i, i + 1, seek, BIG_CHAR, j);
+	      do_test (&json_ctx, getpagesize () - i / 2 - 1, i, i + 1, seek,
+		       SMALL_CHAR, j);
+	    }
+	  if (seek == 0)
+	    {
+	      break;
+	    }
+	}
     }
 
-  for (i = 0; i < 32; ++i)
-    {
-      do_test (0, i, i + 1, 0, SMALL_CHAR);
-      do_test (0, i, i + 1, 0, BIG_CHAR);
-    }
+  json_array_end (&json_ctx);
+  json_attr_object_end (&json_ctx);
+  json_attr_object_end (&json_ctx);
+  json_document_end (&json_ctx);
 
   return ret;
 }