From 02e6fb3c3422b8af26133638bca38c8a5a5fa3fb Mon Sep 17 00:00:00 2001
From: Rusty Russell <rusty@rustcorp.com.au>
Date: Thu, 25 Jun 2015 15:28:52 +0930
Subject: [PATCH] crypto/sha256: add benchmark.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
---
 ccan/crypto/sha256/benchmarks/Makefile        | 10 ++++++++
 .../sha256/benchmarks/double-sha-bench.c      | 23 +++++++++++++++++++
 2 files changed, 33 insertions(+)
 create mode 100644 ccan/crypto/sha256/benchmarks/Makefile
 create mode 100644 ccan/crypto/sha256/benchmarks/double-sha-bench.c

diff --git a/ccan/crypto/sha256/benchmarks/Makefile b/ccan/crypto/sha256/benchmarks/Makefile
new file mode 100644
index 00000000..9621962a
--- /dev/null
+++ b/ccan/crypto/sha256/benchmarks/Makefile
@@ -0,0 +1,10 @@
+CCANDIR := ../../../../
+CFLAGS := -Wall -I$(CCANDIR) -O3 -flto
+LDFLAGS := -O3 -flto
+
+double-sha-bench: double-sha-bench.o ccan-time.o ccan-crypto-sha256.o
+
+ccan-crypto-sha256.o: $(CCANDIR)/ccan/crypto/sha256/sha256.c
+	$(CC) $(CFLAGS) -c -o $@ $<
+ccan-time.o: $(CCANDIR)/ccan/time/time.c
+	$(CC) $(CFLAGS) -c -o $@ $<
diff --git a/ccan/crypto/sha256/benchmarks/double-sha-bench.c b/ccan/crypto/sha256/benchmarks/double-sha-bench.c
new file mode 100644
index 00000000..93fd9d31
--- /dev/null
+++ b/ccan/crypto/sha256/benchmarks/double-sha-bench.c
@@ -0,0 +1,23 @@
+/* Bitcoin does a lot of SHA of SHA.  Benchmark that. */
+#include <ccan/crypto/sha256/sha256.h>
+#include <ccan/time/time.h>
+#include <stdio.h>
+
+int main(int argc, char *argv[])
+{
+	struct timeabs start;
+	struct timerel diff;
+	size_t i, n;
+	struct sha256 h;
+
+	n = atoi(argv[1] ? argv[1] : "1000000");
+	sha256(&h, &n, sizeof(n));
+	start = time_now();
+	for (i = 0; i < n; i++)
+		sha256(&h, &h, sizeof(h));
+	diff = time_divide(time_between(time_now(), start), n);
+	printf("Hashing time for %02x%02x%02x%02x%02x%02x... is %llu nsec\n",
+	       h.u.u8[0], h.u.u8[1], h.u.u8[2], h.u.u8[3], h.u.u8[4], h.u.u8[5],
+	       (unsigned long long)time_to_nsec(diff));
+	return 0;
+}
-- 
2.39.2