Apply fixes and speedups

test/libc/runtime/qsort_test.c

@@ -0,0 +1,90 @@
+/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
+│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8                                :vi│
+╞══════════════════════════════════════════════════════════════════════════════╡
+│ Copyright 2020 Justine Alexandra Roberts Tunney                              │
+│                                                                              │
+│ Permission to use, copy, modify, and/or distribute this software for         │
+│ any purpose with or without fee is hereby granted, provided that the         │
+│ above copyright notice and this permission notice appear in all copies.      │
+│                                                                              │
+│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL                │
+│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED                │
+│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE             │
+│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL         │
+│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR        │
+│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER               │
+│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
+│ PERFORMANCE OF THIS SOFTWARE.                                                │
+╚─────────────────────────────────────────────────────────────────────────────*/
+#include "libc/alg/alg.h"
+#include "libc/bits/bits.h"
+#include "libc/macros.internal.h"
+#include "libc/mem/mem.h"
+#include "libc/nexgen32e/bsr.h"
+#include "libc/rand/rand.h"
+#include "libc/runtime/gc.internal.h"
+#include "libc/str/str.h"
+#include "libc/testlib/ezbench.h"
+#include "libc/testlib/testlib.h"
+
+int CompareLong(const void *a, const void *b) {
+  const long *x = a;
+  const long *y = b;
+  if (*x < *y) return -1;
+  if (*x > *y) return +1;
+  return 0;
+}
+
+unsigned long doge(unsigned long x) {
+  unsigned long t = 1;
+  while (t < x - t) {
+    t += t;
+  }
+  return t;
+}
+
+unsigned long B(unsigned long x) {
+  return 1ul << bsrl(x - 1);
+}
+
+TEST(eh, eu) {
+  int i;
+  for (i = 2; i < 9999; ++i) {
+    ASSERT_EQ(doge(i), B(i), "%d", i);
+  }
+}
+
+TEST(qsort, test) {
+  const int32_t A[][2] = {{4, 'a'},   {65, 'b'}, {2, 'c'}, {-31, 'd'},
+                          {0, 'e'},   {99, 'f'}, {2, 'g'}, {83, 'h'},
+                          {782, 'i'}, {1, 'j'}};
+  const int32_t B[][2] = {{-31, 'd'}, {0, 'e'},  {1, 'j'},  {2, 'c'},
+                          {2, 'g'},   {4, 'a'},  {65, 'b'}, {83, 'h'},
+                          {99, 'f'},  {782, 'i'}};
+  int32_t(*M)[2] = malloc(sizeof(A));
+  memcpy(M, B, sizeof(A));
+  qsort(M, ARRAYLEN(A), sizeof(*M), cmpsl);
+  EXPECT_EQ(0, memcmp(M, B, sizeof(B)));
+  free(M);
+}
+
+TEST(longsort, test) {
+  size_t n = 5000;
+  long *a = gc(calloc(n, sizeof(long)));
+  long *b = gc(calloc(n, sizeof(long)));
+  rngset(a, n * sizeof(long), 0, 0);
+  memcpy(b, a, n * sizeof(long));
+  qsort(a, n, sizeof(long), CompareLong);
+  longsort(b, n);
+  ASSERT_EQ(0, memcmp(b, a, n * sizeof(long)));
+}
+
+BENCH(qsort, bench) {
+  size_t n = 1000;
+  long *p1 = gc(malloc(n * sizeof(long)));
+  long *p2 = gc(malloc(n * sizeof(long)));
+  rngset(p1, n * sizeof(long), 0, 0);
+  EZBENCH2("qsort", memcpy(p2, p1, n * sizeof(long)),
+           qsort(p2, n, sizeof(long), CompareLong));
+  EZBENCH2("longsort", memcpy(p2, p1, n * sizeof(long)), longsort(p2, n));
+}

test/libc/runtime/test.mk

@@ -24,6 +24,7 @@ TEST_LIBC_RUNTIME_CHECKS =					\
 
 TEST_LIBC_RUNTIME_DIRECTDEPS =					\
 	LIBC_ALG						\
+	LIBC_BITS						\
 	LIBC_CALLS						\
 	LIBC_FMT						\
 	LIBC_INTRIN						\