[PATCH v4 1/4] lib/math/test_div64: add some edge cases relevant to __div64_const32()
From: Nicolas Pitre
Date: Thu Oct 03 2024 - 17:18:54 EST
From: Nicolas Pitre <npitre@xxxxxxxxxxxx>
Be sure to test the extreme cases with and without bias.
Signed-off-by: Nicolas Pitre <npitre@xxxxxxxxxxxx>
---
lib/math/test_div64.c | 85 ++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 83 insertions(+), 2 deletions(-)
diff --git a/lib/math/test_div64.c b/lib/math/test_div64.c
index c15edd688d..3cd699b654 100644
--- a/lib/math/test_div64.c
+++ b/lib/math/test_div64.c
@@ -26,6 +26,9 @@ static const u64 test_div64_dividends[] = {
0x0072db27380dd689,
0x0842f488162e2284,
0xf66745411d8ab063,
+ 0xfffffffffffffffb,
+ 0xfffffffffffffffc,
+ 0xffffffffffffffff,
};
#define SIZE_DIV64_DIVIDENDS ARRAY_SIZE(test_div64_dividends)
@@ -37,7 +40,10 @@ static const u64 test_div64_dividends[] = {
#define TEST_DIV64_DIVISOR_5 0x0008a880
#define TEST_DIV64_DIVISOR_6 0x003fd3ae
#define TEST_DIV64_DIVISOR_7 0x0b658fac
-#define TEST_DIV64_DIVISOR_8 0xdc08b349
+#define TEST_DIV64_DIVISOR_8 0x80000001
+#define TEST_DIV64_DIVISOR_9 0xdc08b349
+#define TEST_DIV64_DIVISOR_A 0xfffffffe
+#define TEST_DIV64_DIVISOR_B 0xffffffff
static const u32 test_div64_divisors[] = {
TEST_DIV64_DIVISOR_0,
@@ -49,13 +55,16 @@ static const u32 test_div64_divisors[] = {
TEST_DIV64_DIVISOR_6,
TEST_DIV64_DIVISOR_7,
TEST_DIV64_DIVISOR_8,
+ TEST_DIV64_DIVISOR_9,
+ TEST_DIV64_DIVISOR_A,
+ TEST_DIV64_DIVISOR_B,
};
#define SIZE_DIV64_DIVISORS ARRAY_SIZE(test_div64_divisors)
static const struct {
u64 quotient;
u32 remainder;
-} test_div64_results[SIZE_DIV64_DIVISORS][SIZE_DIV64_DIVIDENDS] = {
+} test_div64_results[SIZE_DIV64_DIVIDENDS][SIZE_DIV64_DIVISORS] = {
{
{ 0x0000000013045e47, 0x00000001 },
{ 0x000000000161596c, 0x00000030 },
@@ -65,6 +74,9 @@ static const struct {
{ 0x00000000000013c4, 0x0004ce80 },
{ 0x00000000000002ae, 0x001e143c },
{ 0x000000000000000f, 0x0033e56c },
+ { 0x0000000000000001, 0x2b27507f },
+ { 0x0000000000000000, 0xab275080 },
+ { 0x0000000000000000, 0xab275080 },
{ 0x0000000000000000, 0xab275080 },
}, {
{ 0x00000001c45c02d1, 0x00000000 },
@@ -75,7 +87,10 @@ static const struct {
{ 0x000000000001d637, 0x0004e5d9 },
{ 0x0000000000003fc9, 0x000713bb },
{ 0x0000000000000165, 0x029abe7d },
+ { 0x000000000000001f, 0x673c193a },
{ 0x0000000000000012, 0x6e9f7e37 },
+ { 0x000000000000000f, 0xe73c1977 },
+ { 0x000000000000000f, 0xe73c1968 },
}, {
{ 0x000000197a3a0cf7, 0x00000002 },
{ 0x00000001d9632e5c, 0x00000021 },
@@ -85,7 +100,10 @@ static const struct {
{ 0x00000000001a7bb3, 0x00072331 },
{ 0x00000000000397ad, 0x0002c61b },
{ 0x000000000000141e, 0x06ea2e89 },
+ { 0x00000000000001ca, 0x4c0a72e7 },
{ 0x000000000000010a, 0xab002ad7 },
+ { 0x00000000000000e5, 0x4c0a767b },
+ { 0x00000000000000e5, 0x4c0a7596 },
}, {
{ 0x0000017949e37538, 0x00000001 },
{ 0x0000001b62441f37, 0x00000055 },
@@ -95,7 +113,10 @@ static const struct {
{ 0x0000000001882ec6, 0x0005cbf9 },
{ 0x000000000035333b, 0x0017abdf },
{ 0x00000000000129f1, 0x0ab4520d },
+ { 0x0000000000001a87, 0x18ff0472 },
{ 0x0000000000000f6e, 0x8ac0ce9b },
+ { 0x0000000000000d43, 0x98ff397f },
+ { 0x0000000000000d43, 0x98ff2c3c },
}, {
{ 0x000011f321a74e49, 0x00000006 },
{ 0x0000014d8481d211, 0x0000005b },
@@ -105,7 +126,10 @@ static const struct {
{ 0x0000000012a88828, 0x00036c97 },
{ 0x000000000287f16f, 0x002c2a25 },
{ 0x00000000000e2cc7, 0x02d581e3 },
+ { 0x0000000000014318, 0x2ee07d7f },
{ 0x000000000000bbf4, 0x1ba08c03 },
+ { 0x000000000000a18c, 0x2ee303af },
+ { 0x000000000000a18c, 0x2ee26223 },
}, {
{ 0x0000d8db8f72935d, 0x00000005 },
{ 0x00000fbd5aed7a2e, 0x00000002 },
@@ -115,7 +139,10 @@ static const struct {
{ 0x00000000e16b20fa, 0x0002a14a },
{ 0x000000001e940d22, 0x00353b2e },
{ 0x0000000000ab40ac, 0x06fba6ba },
+ { 0x00000000000f3f70, 0x0af7eeda },
{ 0x000000000008debd, 0x72d98365 },
+ { 0x0000000000079fb8, 0x0b166dba },
+ { 0x0000000000079fb8, 0x0b0ece02 },
}, {
{ 0x000cc3045b8fc281, 0x00000000 },
{ 0x0000ed1f48b5c9fc, 0x00000079 },
@@ -125,7 +152,10 @@ static const struct {
{ 0x0000000d43fce827, 0x00082b09 },
{ 0x00000001ccaba11a, 0x0037e8dd },
{ 0x000000000a13f729, 0x0566dffd },
+ { 0x0000000000e5b64e, 0x3728203b },
{ 0x000000000085a14b, 0x23d36726 },
+ { 0x000000000072db27, 0x38f38cd7 },
+ { 0x000000000072db27, 0x3880b1b0 },
}, {
{ 0x00eafeb9c993592b, 0x00000001 },
{ 0x00110e5befa9a991, 0x00000048 },
@@ -135,7 +165,10 @@ static const struct {
{ 0x000000f4459740fc, 0x00084484 },
{ 0x0000002122c47bf9, 0x002ca446 },
{ 0x00000000b9936290, 0x004979c4 },
+ { 0x000000001085e910, 0x05a83974 },
{ 0x00000000099ca89d, 0x9db446bf },
+ { 0x000000000842f488, 0x26b40b94 },
+ { 0x000000000842f488, 0x1e71170c },
}, {
{ 0x1b60cece589da1d2, 0x00000001 },
{ 0x01fcb42be1453f5b, 0x0000004f },
@@ -145,7 +178,49 @@ static const struct {
{ 0x00001c757dfab350, 0x00048863 },
{ 0x000003dc4979c652, 0x00224ea7 },
{ 0x000000159edc3144, 0x06409ab3 },
+ { 0x00000001ecce8a7e, 0x30bc25e5 },
{ 0x000000011eadfee3, 0xa99c48a8 },
+ { 0x00000000f6674543, 0x0a593ae9 },
+ { 0x00000000f6674542, 0x13f1f5a5 },
+ }, {
+ { 0x1c71c71c71c71c71, 0x00000002 },
+ { 0x0210842108421084, 0x0000000b },
+ { 0x007f01fc07f01fc0, 0x000000fb },
+ { 0x00014245eabf1f9a, 0x0000a63d },
+ { 0x0000ffffffffffff, 0x0000fffb },
+ { 0x00001d913cecc509, 0x0007937b },
+ { 0x00000402c70c678f, 0x0005bfc9 },
+ { 0x00000016766cb70b, 0x045edf97 },
+ { 0x00000001fffffffb, 0x80000000 },
+ { 0x0000000129d84b3a, 0xa2e8fe71 },
+ { 0x0000000100000001, 0xfffffffd },
+ { 0x0000000100000000, 0xfffffffb },
+ }, {
+ { 0x1c71c71c71c71c71, 0x00000003 },
+ { 0x0210842108421084, 0x0000000c },
+ { 0x007f01fc07f01fc0, 0x000000fc },
+ { 0x00014245eabf1f9a, 0x0000a63e },
+ { 0x0000ffffffffffff, 0x0000fffc },
+ { 0x00001d913cecc509, 0x0007937c },
+ { 0x00000402c70c678f, 0x0005bfca },
+ { 0x00000016766cb70b, 0x045edf98 },
+ { 0x00000001fffffffc, 0x00000000 },
+ { 0x0000000129d84b3a, 0xa2e8fe72 },
+ { 0x0000000100000002, 0x00000000 },
+ { 0x0000000100000000, 0xfffffffc },
+ }, {
+ { 0x1c71c71c71c71c71, 0x00000006 },
+ { 0x0210842108421084, 0x0000000f },
+ { 0x007f01fc07f01fc0, 0x000000ff },
+ { 0x00014245eabf1f9a, 0x0000a641 },
+ { 0x0000ffffffffffff, 0x0000ffff },
+ { 0x00001d913cecc509, 0x0007937f },
+ { 0x00000402c70c678f, 0x0005bfcd },
+ { 0x00000016766cb70b, 0x045edf9b },
+ { 0x00000001fffffffc, 0x00000003 },
+ { 0x0000000129d84b3a, 0xa2e8fe75 },
+ { 0x0000000100000002, 0x00000003 },
+ { 0x0000000100000001, 0x00000000 },
},
};
@@ -208,6 +283,12 @@ static bool __init test_div64(void)
return false;
if (!test_div64_one(dividend, TEST_DIV64_DIVISOR_8, i, 8))
return false;
+ if (!test_div64_one(dividend, TEST_DIV64_DIVISOR_9, i, 9))
+ return false;
+ if (!test_div64_one(dividend, TEST_DIV64_DIVISOR_A, i, 10))
+ return false;
+ if (!test_div64_one(dividend, TEST_DIV64_DIVISOR_B, i, 11))
+ return false;
for (j = 0; j < SIZE_DIV64_DIVISORS; j++) {
if (!test_div64_one(dividend, test_div64_divisors[j],
i, j))
--
2.46.1