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Supply signed division to fix ARM compilation.

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Previously we supplied only unsigned divisions on platforms that need software
division.
Yet compiler may itself use a signed division. A typical example would be a
difference between 2 pointers which involves division by object size.
This commit is contained in:
Vladimir Serbinenko 2015-02-22 17:24:28 +01:00
parent e1d4520bfb
commit f034fab620
6 changed files with 198 additions and 51 deletions
Download patch file Download diff file Expand all files Collapse all files

73
grub-core/tests/div_test.c
View file

@ -97,6 +97,72 @@ test64 (grub_uint64_t a, grub_uint64_t b)
#endif
}
static grub_int64_t
abs64(grub_int64_t a)
{
return a > 0 ? a : -a;
}
static void
test32s (grub_int32_t a, grub_int32_t b)
{
grub_int64_t q, r;
if (b == 0)
return;
q = grub_divmod64s (a, b, &r);
grub_test_assert (a > 0 ? r >= 0 : r <= 0, "remainder sign mismatch: %lld %% %lld = %lld",
(long long) a, (long long) b, (long long) r);
grub_test_assert (((a > 0) == (b > 0)) ? q >= 0 : q <= 0, "quotient sign mismatch: %lld / %lld = %lld",
(long long) a, (long long) b, (long long) q);
grub_test_assert (abs64(r) < abs64(b), "remainder is larger than dividend: %lld %% %lld = %lld",
(long long) a, (long long) b, (long long) r);
grub_test_assert (q * b + r == a, "division doesn't satisfy base property: %lld * %lld + %lld != %lld", (long long) q, (long long) b, (long long) r,
(long long) a);
if (0) { grub_test_assert (q == (a / b),
"C compiler division failure in 0x%llx, 0x%llx", (long long) a, (long long) b);
grub_test_assert (r == (a % b),
"C compiler modulo failure in 0x%llx, 0x%llx", (long long) a, (long long) b);
}
}
static void
test64s (grub_int64_t a, grub_int64_t b)
{
grub_int64_t q, r;
q = grub_divmod64s (a, b, &r);
grub_test_assert (a > 0 ? r >= 0 : r <= 0, "remainder sign mismatch: %lld %% %lld = %lld",
(long long) a, (long long) b, (long long) r);
grub_test_assert (((a > 0) == (b > 0)) ? q >= 0 : q <= 0, "quotient sign mismatch: %lld / %lld = %lld",
(long long) a, (long long) b, (long long) q);
grub_test_assert (abs64(r) < abs64(b), "remainder is larger than dividend: %lld %% %lld = %lld",
(long long) a, (long long) b, (long long) r);
grub_test_assert (q * b + r == a, "division doesn't satisfy base property: 0x%llx * 0x%llx + 0x%llx != 0x%llx", (long long) q, (long long) b, (long long) r,
(long long) a);
#if GRUB_TARGET_SIZEOF_VOID_P == 8
grub_test_assert (q == (a / b),
"C compiler division failure in 0x%llx, 0x%llx", (long long) a, (long long) b);
grub_test_assert (r == (a % b),
"C compiler modulo failure in 0x%llx, 0x%llx", (long long) a, (long long) b);
#endif
}
static void
test_all(grub_uint64_t a, grub_uint64_t b)
{
test64 (a, b);
test32 (a, b);
test64s (a, b);
test32s (a, b);
test64s (a, -b);
test32s (a, -b);
test64s (-a, b);
test32s (-a, b);
test64s (-a, -b);
test32s (-a, -b);
}
static void
div_test (void)
{
@ -105,8 +171,7 @@ div_test (void)
for (i = 0; i < ARRAY_SIZE (vectors); i++)
{
test64 (vectors[i][0], vectors[i][1]);
test32 (vectors[i][0], vectors[i][1]);
test_all (vectors[i][0], vectors[i][1]);
}
for (i = 0; i < 40000; i++)
{
@ -116,9 +181,7 @@ div_test (void)
b = 1;
if (a == 0)
a = 1;
test64 (a, b);
test32 (a, b);
test_all (a, b);
}
}