Clean up ecmult_bench to make space for more benchmarks

Author: jonasnick

src/bench_ecmult.c

@@ -28,19 +28,26 @@ typedef struct {
     secp256k1_gej* expected_output;
     secp256k1_ecmult_multi_func ecmult_multi;
 
-    /* Changes per test */
+    /* Changes per benchmark */
     size_t count;
     int includes_g;
 
-    /* Changes per test iteration */
+    /* Changes per benchmark iteration, used to pick different scalars and pubkeys
+     * in each run. */
     size_t offset1;
     size_t offset2;
 
-    /* Test output. */
+    /* Benchmark output. */
     secp256k1_gej* output;
 } bench_data;
 
-static int bench_callback(secp256k1_scalar* sc, secp256k1_ge* ge, size_t idx, void* arg) {
+/* Hashes x into [0, POINTS) twice and store the result in offset1 and offset2. */
+static void hash_into_offset(bench_data* data, size_t x) {
+    data->offset1 = (x * 0x537b7f6f + 0x8f66a481) % POINTS;
+    data->offset2 = (x * 0x7f6f537b + 0x6a1a8f49) % POINTS;
+}
+
+static int bench_ecmult_multi_callback(secp256k1_scalar* sc, secp256k1_ge* ge, size_t idx, void* arg) {
     bench_data* data = (bench_data*)arg;
     if (data->includes_g) ++idx;
     if (idx == 0) {
@@ -53,7 +60,7 @@ static int bench_callback(secp256k1_scalar* sc, secp256k1_ge* ge, size_t idx, vo
     return 1;
 }
 
-static void bench_ecmult(void* arg, int iters) {
+static void bench_ecmult_multi(void* arg, int iters) {
     bench_data* data = (bench_data*)arg;
 
     int includes_g = data->includes_g;
@@ -62,19 +69,18 @@ static void bench_ecmult(void* arg, int iters) {
     iters = iters / data->count;
 
     for (iter = 0; iter < iters; ++iter) {
-        data->ecmult_multi(&data->ctx->error_callback, &data->ctx->ecmult_ctx, data->scratch, &data->output[iter], data->includes_g ? &data->scalars[data->offset1] : NULL, bench_callback, arg, count - includes_g);
+        data->ecmult_multi(&data->ctx->error_callback, &data->ctx->ecmult_ctx, data->scratch, &data->output[iter], data->includes_g ? &data->scalars[data->offset1] : NULL, bench_ecmult_multi_callback, arg, count - includes_g);
         data->offset1 = (data->offset1 + count) % POINTS;
         data->offset2 = (data->offset2 + count - 1) % POINTS;
     }
 }
 
-static void bench_ecmult_setup(void* arg) {
+static void bench_ecmult_multi_setup(void* arg) {
     bench_data* data = (bench_data*)arg;
-    data->offset1 = (data->count * 0x537b7f6f + 0x8f66a481) % POINTS;
-    data->offset2 = (data->count * 0x7f6f537b + 0x6a1a8f49) % POINTS;
+    hash_into_offset(data, data->count);
 }
 
-static void bench_ecmult_teardown(void* arg, int iters) {
+static void bench_ecmult_multi_teardown(void* arg, int iters) {
     bench_data* data = (bench_data*)arg;
     int iter;
     iters = iters / data->count;
@@ -102,7 +108,7 @@ static void generate_scalar(uint32_t num, secp256k1_scalar* scalar) {
     CHECK(!overflow);
 }
 
-static void run_test(bench_data* data, size_t count, int includes_g, int num_iters) {
+static void run_ecmult_multi_bench(bench_data* data, size_t count, int includes_g, int num_iters) {
     char str[32];
     static const secp256k1_scalar zero = SECP256K1_SCALAR_CONST(0, 0, 0, 0, 0, 0, 0, 0);
     size_t iters = 1 + num_iters / count;
@@ -112,8 +118,7 @@ static void run_test(bench_data* data, size_t count, int includes_g, int num_ite
     data->includes_g = includes_g;
 
     /* Compute (the negation of) the expected results directly. */
-    data->offset1 = (data->count * 0x537b7f6f + 0x8f66a481) % POINTS;
-    data->offset2 = (data->count * 0x7f6f537b + 0x6a1a8f49) % POINTS;
+    hash_into_offset(data, data->count);
     for (iter = 0; iter < iters; ++iter) {
         secp256k1_scalar tmp;
         secp256k1_scalar total = data->scalars[(data->offset1++) % POINTS];
@@ -127,8 +132,8 @@ static void run_test(bench_data* data, size_t count, int includes_g, int num_ite
     }
 
     /* Run the benchmark. */
-    sprintf(str, includes_g ? "ecmult_%ig" : "ecmult_%i", (int)count);
-    run_benchmark(str, bench_ecmult, bench_ecmult_setup, bench_ecmult_teardown, data, 10, count * iters);
+    sprintf(str, includes_g ? "ecmult_multi %ig" : "ecmult_multi %i", (int)count);
+    run_benchmark(str, bench_ecmult_multi, bench_ecmult_multi_setup, bench_ecmult_multi_teardown, data, 10, count * iters);
 }
 
 int main(int argc, char **argv) {
@@ -185,7 +190,7 @@ int main(int argc, char **argv) {
     free(pubkeys_gej);
 
     for (i = 1; i <= 8; ++i) {
-        run_test(&data, i, 1, iters);
+        run_ecmult_multi_bench(&data, i, 1, iters);
     }
 
     /* This is disabled with low count of iterations because the loop runs 77 times even with iters=1
@@ -194,7 +199,7 @@ int main(int argc, char **argv) {
      if (iters > 2) {
         for (p = 0; p <= 11; ++p) {
             for (i = 9; i <= 16; ++i) {
-                run_test(&data, i << p, 1, iters);
+                run_ecmult_multi_bench(&data, i << p, 1, iters);
             }
         }
     }