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Re: [PATCH v3] Add random memcpy test
H.J. Lu wrote:
>
> I like it. But with GCC 6, I got
>
> bench-memcpy-random.c: In function ‘init_copy_distribution’:
> bench-memcpy-random.c:81:3: error: suggest parentheses around
> assignment used as truth value [-Werror=parentheses]
> for (n = i = 0; freq = size_freq[i].freq; i++)
I see, I've added those so it now builds with -Werror:
---
diff --git a/benchtests/Makefile b/benchtests/Makefile
index 81edf8a933ce7371ac60c118a4a46daee6391800..a96e9533b3b2d7223c2ce90a723b6a434ba1a1ea 100644
--- a/benchtests/Makefile
+++ b/benchtests/Makefile
@@ -37,7 +37,7 @@ string-benchset := bcopy bzero memccpy memchr memcmp memcpy memmem memmove \
strcat strchr strchrnul strcmp strcpy strcspn strlen \
strncasecmp strncat strncmp strncpy strnlen strpbrk strrchr \
strspn strstr strcpy_chk stpcpy_chk memrchr strsep strtok \
- strcoll memcpy-large memmove-large memset-large
+ strcoll memcpy-large memcpy-random memmove-large memset-large
# Build and run locale-dependent benchmarks only if we're building natively.
ifeq (no,$(cross-compiling))
diff --git a/benchtests/bench-memcpy-random.c b/benchtests/bench-memcpy-random.c
new file mode 100644
index 0000000000000000000000000000000000000000..4cd620966d4e2b6790830ab005074c2b19ab922c
--- /dev/null
+++ b/benchtests/bench-memcpy-random.c
@@ -0,0 +1,157 @@
+/* Measure memcpy performance.
+ Copyright (C) 2016-2017 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 MIN_PAGE_SIZE 131072
+#define TEST_MAIN
+#define TEST_NAME "memcpy-random"
+#include "bench-string.h"
+#include <assert.h>
+
+IMPL (memcpy, 0)
+
+#define NUM_COPIES 4096
+
+typedef struct { uint16_t size; uint16_t freq; } freq_data_t;
+typedef struct { uint8_t align; uint8_t freq; } align_data_t;
+
+#define SIZE_NUM 1024
+#define SIZE_MASK (SIZE_NUM-1)
+static uint8_t size_arr[SIZE_NUM];
+
+/* Frequency data for memcpy of less than 256 bytes based on SPEC2006. */
+static freq_data_t size_freq[] =
+{
+ { 8, 576}, {104, 94}, { 24, 78}, { 48, 58}, { 32, 48}, { 16, 46},
+ { 1, 30}, { 96, 12}, { 72, 11}, {216, 11}, {192, 8}, { 12, 7},
+ {144, 5}, { 2, 4}, { 64, 4}, {120, 4}, { 4, 3}, { 40, 2},
+ { 7, 2}, {168, 2}, {160, 2}, {128, 1}, { 3, 1}, { 9, 1},
+ {176, 1}, {240, 1}, { 11, 1}, { 0, 1}, { 5, 1}, { 6, 1},
+ { 80, 1}, { 52, 1}, {152, 1}, { 10, 1}, { 56, 1}, { 51, 1},
+ { 14, 1}, {208, 1}, { 0, 0}
+};
+
+#define ALIGN_NUM 256
+#define ALIGN_MASK (ALIGN_NUM-1)
+static uint8_t src_align_arr[ALIGN_NUM];
+static uint8_t dst_align_arr[ALIGN_NUM];
+
+/* Source alignment frequency for memcpy based on SPEC2006. */
+static align_data_t src_align_freq[] =
+{
+ {16, 144}, {8, 86}, {3, 23}, {1, 3}, {0, 0}
+};
+
+/* Destination alignment frequency for memcpy based on SPEC2006. */
+static align_data_t dst_align_freq[] =
+{
+ {16, 197}, {8, 30}, {3, 23}, {1, 6}, {0, 0}
+};
+
+typedef struct
+{
+ uint16_t src;
+ uint16_t dst;
+ uint16_t len;
+} copy_t;
+
+static copy_t copy[NUM_COPIES];
+
+typedef char *(*proto_t) (char *, const char *, size_t);
+
+static void
+init_copy_distribution (void)
+{
+ int i, j, freq, size, n;
+
+ for (n = i = 0; (freq = size_freq[i].freq) != 0; i++)
+ for (j = 0, size = size_freq[i].size; j < freq; j++)
+ size_arr[n++] = size;
+ assert (n == SIZE_NUM);
+
+ for (n = i = 0; (freq = src_align_freq[i].freq) != 0; i++)
+ for (j = 0, size = src_align_freq[i].align; j < freq; j++)
+ src_align_arr[n++] = size - 1;
+ assert (n == ALIGN_NUM);
+
+ for (n = i = 0; (freq = dst_align_freq[i].freq) != 0; i++)
+ for (j = 0, size = dst_align_freq[i].align; j < freq; j++)
+ dst_align_arr[n++] = size - 1;
+ assert (n == ALIGN_NUM);
+}
+
+
+static void
+do_one_test (impl_t *impl, char *dst, char *src, copy_t *copy, size_t n)
+{
+ timing_t start, stop, cur;
+ size_t iters = INNER_LOOP_ITERS * 20;
+
+ TIMING_NOW (start);
+ for (int i = 0; i < iters; ++i)
+ for (int j = 0; j < n; j++)
+ CALL (impl, dst + copy[j].dst, src + copy[j].src, copy[j].len);
+ TIMING_NOW (stop);
+
+ TIMING_DIFF (cur, start, stop);
+
+ TIMING_PRINT_MEAN ((double) cur, (double) iters);
+}
+
+static void
+do_test (size_t max_size)
+{
+ for (int i = 0; i < max_size; i++)
+ buf1[i] = i * 3;
+
+ /* Create a random set of copies with the given size and alignment
+ distributions. */
+ for (int i = 0; i < NUM_COPIES; i++)
+ {
+ copy[i].dst = (rand () & (max_size - 1)) | 1;
+ copy[i].dst &= ~dst_align_arr[rand () & ALIGN_MASK];
+ copy[i].src = (rand () & (max_size - 1)) | 3;
+ copy[i].src &= ~src_align_arr[rand () & ALIGN_MASK];
+ copy[i].len = size_arr[rand () & SIZE_MASK];
+ }
+
+ printf ("Memory size %6zd:", max_size);
+
+ FOR_EACH_IMPL (impl, 0)
+ do_one_test (impl, (char *) buf2, (char *) buf1, copy, NUM_COPIES);
+
+ putchar ('\n');
+}
+
+int
+test_main (void)
+{
+ test_init ();
+ init_copy_distribution ();
+
+ printf ("%23s", "");
+ FOR_EACH_IMPL (impl, 0)
+ printf ("\t%s", impl->name);
+ putchar ('\n');
+
+ for (int i = 4; i <= 64; i = i * 2)
+ do_test (i * 1024);
+
+ return ret;
+}
+
+#include <support/test-driver.c>