* [PATCH v1 1/1] base64: Unroll the tables initialisers
@ 2025-11-03 19:05 Andy Shevchenko
2025-11-03 19:17 ` Andy Shevchenko
2025-11-03 22:18 ` David Laight
0 siblings, 2 replies; 6+ messages in thread
From: Andy Shevchenko @ 2025-11-03 19:05 UTC (permalink / raw)
To: Andrew Morton, Guan-Chun Wu, Kuan-Wei Chiu, linux-kernel
Cc: David Laight, Andy Shevchenko
Currently the initialisers of the tables have duplicate indices.
This prevents from building with `make W=1`.
To address the issue, unroll the table initialisers with generated
arrays by the following Python excerpt:
CHARS = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"
def gen_table(ch62, ch63):
table = [ 0xff ] * 256
for idx, char in enumerate(CHARS):
table[ord(char)] = idx
table[ord(ch62)] = 62
table[ord(ch63)] = 63
for i in range(0, len(table), 8):
print (f"\t{', '.join(f"0x{c:02x}" for c in table[i:i+8])},\t/* {i:-3d} - {i+7:-3d} */")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
lib/base64.c | 115 +++++++++++++++++++++++++++++++++++++++++++++------
1 file changed, 102 insertions(+), 13 deletions(-)
diff --git a/lib/base64.c b/lib/base64.c
index bcdbd411d63b..0a7c15c5c1b6 100644
--- a/lib/base64.c
+++ b/lib/base64.c
@@ -21,20 +21,109 @@ static const char base64_tables[][65] = {
[BASE64_IMAP] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+,",
};
-#define BASE64_REV_INIT(ch_62, ch_63) { \
- [0 ... 255] = -1, \
- ['A'] = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, \
- 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, \
- ['a'] = 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, \
- 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, \
- ['0'] = 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, \
- [ch_62] = 62, [ch_63] = 63, \
-}
-
static const s8 base64_rev_maps[][256] = {
- [BASE64_STD] = BASE64_REV_INIT('+', '/'),
- [BASE64_URLSAFE] = BASE64_REV_INIT('-', '_'),
- [BASE64_IMAP] = BASE64_REV_INIT('+', ',')
+ [BASE64_STD] = {
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 0 - 7 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 8 - 15 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 16 - 23 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 24 - 31 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 32 - 39 */
+ 0xff, 0xff, 0xff, 0x3e, 0xff, 0xff, 0xff, 0x3f, /* 40 - 47 */
+ 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, 0x3b, /* 48 - 55 */
+ 0x3c, 0x3d, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 56 - 63 */
+ 0xff, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, /* 64 - 71 */
+ 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, /* 72 - 79 */
+ 0x0f, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, /* 80 - 87 */
+ 0x17, 0x18, 0x19, 0xff, 0xff, 0xff, 0xff, 0xff, /* 88 - 95 */
+ 0xff, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 0x20, /* 96 - 103 */
+ 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, /* 104 - 111 */
+ 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f, 0x30, /* 112 - 119 */
+ 0x31, 0x32, 0x33, 0xff, 0xff, 0xff, 0xff, 0xff, /* 120 - 127 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 128 - 135 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 136 - 143 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 144 - 151 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 152 - 159 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 160 - 167 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 168 - 175 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 176 - 183 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 184 - 191 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 192 - 199 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 200 - 207 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 208 - 215 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 216 - 223 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 224 - 231 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 232 - 239 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 240 - 247 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 248 - 255 */
+ },
+ [BASE64_URLSAFE] = {
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 0 - 7 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 8 - 15 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 16 - 23 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 24 - 31 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 32 - 39 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0x3e, 0xff, 0xff, /* 40 - 47 */
+ 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, 0x3b, /* 48 - 55 */
+ 0x3c, 0x3d, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 56 - 63 */
+ 0xff, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, /* 64 - 71 */
+ 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, /* 72 - 79 */
+ 0x0f, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, /* 80 - 87 */
+ 0x17, 0x18, 0x19, 0xff, 0xff, 0xff, 0xff, 0x3f, /* 88 - 95 */
+ 0xff, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 0x20, /* 96 - 103 */
+ 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, /* 104 - 111 */
+ 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f, 0x30, /* 112 - 119 */
+ 0x31, 0x32, 0x33, 0xff, 0xff, 0xff, 0xff, 0xff, /* 120 - 127 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 128 - 135 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 136 - 143 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 144 - 151 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 152 - 159 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 160 - 167 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 168 - 175 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 176 - 183 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 184 - 191 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 192 - 199 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 200 - 207 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 208 - 215 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 216 - 223 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 224 - 231 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 232 - 239 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 240 - 247 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 248 - 255 */
+ },
+ [BASE64_IMAP] = {
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 0 - 7 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 8 - 15 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 16 - 23 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 24 - 31 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 32 - 39 */
+ 0xff, 0xff, 0xff, 0x3e, 0x3f, 0xff, 0xff, 0xff, /* 40 - 47 */
+ 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, 0x3b, /* 48 - 55 */
+ 0x3c, 0x3d, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 56 - 63 */
+ 0xff, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, /* 64 - 71 */
+ 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, /* 72 - 79 */
+ 0x0f, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, /* 80 - 87 */
+ 0x17, 0x18, 0x19, 0xff, 0xff, 0xff, 0xff, 0xff, /* 88 - 95 */
+ 0xff, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 0x20, /* 96 - 103 */
+ 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, /* 104 - 111 */
+ 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f, 0x30, /* 112 - 119 */
+ 0x31, 0x32, 0x33, 0xff, 0xff, 0xff, 0xff, 0xff, /* 120 - 127 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 128 - 135 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 136 - 143 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 144 - 151 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 152 - 159 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 160 - 167 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 168 - 175 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 176 - 183 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 184 - 191 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 192 - 199 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 200 - 207 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 208 - 215 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 216 - 223 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 224 - 231 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 232 - 239 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 240 - 247 */
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 248 - 255 */
+ },
};
/**
* base64_encode() - Base64-encode some binary data
--
2.50.1
^ permalink raw reply related [flat|nested] 6+ messages in thread* Re: [PATCH v1 1/1] base64: Unroll the tables initialisers
2025-11-03 19:05 [PATCH v1 1/1] base64: Unroll the tables initialisers Andy Shevchenko
@ 2025-11-03 19:17 ` Andy Shevchenko
2025-11-03 22:18 ` David Laight
1 sibling, 0 replies; 6+ messages in thread
From: Andy Shevchenko @ 2025-11-03 19:17 UTC (permalink / raw)
To: Andrew Morton, Guan-Chun Wu, Kuan-Wei Chiu, linux-kernel; +Cc: David Laight
On Mon, Nov 03, 2025 at 08:05:10PM +0100, Andy Shevchenko wrote:
> Currently the initialisers of the tables have duplicate indices.
> This prevents from building with `make W=1`.
>
> To address the issue, unroll the table initialisers with generated
> arrays by the following Python excerpt:
>
> CHARS = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"
>
> def gen_table(ch62, ch63):
> table = [ 0xff ] * 256
> for idx, char in enumerate(CHARS):
> table[ord(char)] = idx
> table[ord(ch62)] = 62
> table[ord(ch63)] = 63
>
> for i in range(0, len(table), 8):
> print (f"\t{', '.join(f"0x{c:02x}" for c in table[i:i+8])},\t/* {i:-3d} - {i+7:-3d} */")
I haven't added a Fixes tag as the idea to fold this to the initial
contribution.
--
With Best Regards,
Andy Shevchenko
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH v1 1/1] base64: Unroll the tables initialisers
2025-11-03 19:05 [PATCH v1 1/1] base64: Unroll the tables initialisers Andy Shevchenko
2025-11-03 19:17 ` Andy Shevchenko
@ 2025-11-03 22:18 ` David Laight
2025-11-04 8:18 ` Andy Shevchenko
1 sibling, 1 reply; 6+ messages in thread
From: David Laight @ 2025-11-03 22:18 UTC (permalink / raw)
To: Andy Shevchenko; +Cc: Andrew Morton, Guan-Chun Wu, Kuan-Wei Chiu, linux-kernel
On Mon, 3 Nov 2025 20:05:10 +0100
Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote:
> Currently the initialisers of the tables have duplicate indices.
> This prevents from building with `make W=1`.
>
> To address the issue, unroll the table initialisers with generated
> arrays by the following Python excerpt:
>
> CHARS = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"
>
> def gen_table(ch62, ch63):
> table = [ 0xff ] * 256
> for idx, char in enumerate(CHARS):
> table[ord(char)] = idx
> table[ord(ch62)] = 62
> table[ord(ch63)] = 63
>
> for i in range(0, len(table), 8):
> print (f"\t{', '.join(f"0x{c:02x}" for c in table[i:i+8])},\t/* {i:-3d} - {i+7:-3d} */")
>
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
> lib/base64.c | 115 +++++++++++++++++++++++++++++++++++++++++++++------
> 1 file changed, 102 insertions(+), 13 deletions(-)
>
> diff --git a/lib/base64.c b/lib/base64.c
> index bcdbd411d63b..0a7c15c5c1b6 100644
> --- a/lib/base64.c
> +++ b/lib/base64.c
> @@ -21,20 +21,109 @@ static const char base64_tables[][65] = {
> [BASE64_IMAP] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+,",
> };
>
> -#define BASE64_REV_INIT(ch_62, ch_63) { \
> - [0 ... 255] = -1, \
> - ['A'] = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, \
> - 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, \
> - ['a'] = 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, \
> - 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, \
> - ['0'] = 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, \
> - [ch_62] = 62, [ch_63] = 63, \
> -}
> -
> static const s8 base64_rev_maps[][256] = {
> - [BASE64_STD] = BASE64_REV_INIT('+', '/'),
> - [BASE64_URLSAFE] = BASE64_REV_INIT('-', '_'),
> - [BASE64_IMAP] = BASE64_REV_INIT('+', ',')
> + [BASE64_STD] = {
> + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 0 - 7 */
You need to use -1 not 0xff.
> + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 8 - 15 */
> + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 16 - 23 */
> + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 24 - 31 */
> + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 32 - 39 */
Nothing wrong with [ 0 ... 39 ] = -1,
> + 0xff, 0xff, 0xff, 0x3e, 0xff, 0xff, 0xff, 0x3f, /* 40 - 47 */
> + 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, 0x3b, /* 48 - 55 */
> + 0x3c, 0x3d, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 56 - 63 */
> + 0xff, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, /* 64 - 71 */
> + 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, /* 72 - 79 */
> + 0x0f, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, /* 80 - 87 */
> + 0x17, 0x18, 0x19, 0xff, 0xff, 0xff, 0xff, 0xff, /* 88 - 95 */
> + 0xff, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 0x20, /* 96 - 103 */
> + 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, /* 104 - 111 */
> + 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f, 0x30, /* 112 - 119 */
> + 0x31, 0x32, 0x33, 0xff, 0xff, 0xff, 0xff, 0xff, /* 120 - 127 */
> + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 128 - 135 */
> + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 136 - 143 */
> + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 144 - 151 */
> + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 152 - 159 */
> + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 160 - 167 */
> + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 168 - 175 */
> + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 176 - 183 */
> + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 184 - 191 */
> + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 192 - 199 */
> + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 200 - 207 */
> + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 208 - 215 */
> + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 216 - 223 */
> + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 224 - 231 */
> + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 232 - 239 */
> + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 240 - 247 */
> + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 248 - 255 */
> + },
...
This is impenetrable crap...
David
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH v1 1/1] base64: Unroll the tables initialisers
2025-11-03 22:18 ` David Laight
@ 2025-11-04 8:18 ` Andy Shevchenko
2025-11-04 9:07 ` David Laight
0 siblings, 1 reply; 6+ messages in thread
From: Andy Shevchenko @ 2025-11-04 8:18 UTC (permalink / raw)
To: David Laight; +Cc: Andrew Morton, Guan-Chun Wu, Kuan-Wei Chiu, linux-kernel
On Mon, Nov 03, 2025 at 10:18:57PM +0000, David Laight wrote:
> On Mon, 3 Nov 2025 20:05:10 +0100
> Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote:
>
> > Currently the initialisers of the tables have duplicate indices.
> > This prevents from building with `make W=1`.
> >
> > To address the issue, unroll the table initialisers with generated
> > arrays by the following Python excerpt:
> >
> > CHARS = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"
> >
> > def gen_table(ch62, ch63):
> > table = [ 0xff ] * 256
> > for idx, char in enumerate(CHARS):
> > table[ord(char)] = idx
> > table[ord(ch62)] = 62
> > table[ord(ch63)] = 63
> >
> > for i in range(0, len(table), 8):
> > print (f"\t{', '.join(f"0x{c:02x}" for c in table[i:i+8])},\t/* {i:-3d} - {i+7:-3d} */")
...
> > + [BASE64_STD] = {
> > + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 0 - 7 */
>
> You need to use -1 not 0xff.
Whu? The s8 type is pretty much 8-bit, care to explain the point?
> > + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 8 - 15 */
> > + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 16 - 23 */
> > + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 24 - 31 */
> > + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 32 - 39 */
>
> Nothing wrong with [ 0 ... 39 ] = -1,
Have you tried? It's unreadable if we use ranges.
> > + 0xff, 0xff, 0xff, 0x3e, 0xff, 0xff, 0xff, 0x3f, /* 40 - 47 */
> > + 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, 0x3b, /* 48 - 55 */
> > + 0x3c, 0x3d, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 56 - 63 */
> > + 0xff, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, /* 64 - 71 */
> > + 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, /* 72 - 79 */
> > + 0x0f, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, /* 80 - 87 */
> > + 0x17, 0x18, 0x19, 0xff, 0xff, 0xff, 0xff, 0xff, /* 88 - 95 */
> > + 0xff, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 0x20, /* 96 - 103 */
> > + 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, /* 104 - 111 */
> > + 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f, 0x30, /* 112 - 119 */
> > + 0x31, 0x32, 0x33, 0xff, 0xff, 0xff, 0xff, 0xff, /* 120 - 127 */
> > + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 128 - 135 */
> > + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 136 - 143 */
> > + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 144 - 151 */
> > + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 152 - 159 */
> > + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 160 - 167 */
> > + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 168 - 175 */
> > + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 176 - 183 */
> > + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 184 - 191 */
> > + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 192 - 199 */
> > + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 200 - 207 */
> > + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 208 - 215 */
> > + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 216 - 223 */
> > + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 224 - 231 */
> > + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 232 - 239 */
> > + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 240 - 247 */
> > + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 248 - 255 */
> > + },
...
> This is impenetrable crap...
Send your version for the review, please, we still have a build issue here.
But I definitely do not like current state of affairs.
--
With Best Regards,
Andy Shevchenko
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH v1 1/1] base64: Unroll the tables initialisers
2025-11-04 8:18 ` Andy Shevchenko
@ 2025-11-04 9:07 ` David Laight
2025-11-04 9:44 ` Andy Shevchenko
0 siblings, 1 reply; 6+ messages in thread
From: David Laight @ 2025-11-04 9:07 UTC (permalink / raw)
To: Andy Shevchenko; +Cc: Andrew Morton, Guan-Chun Wu, Kuan-Wei Chiu, linux-kernel
On Tue, 4 Nov 2025 10:18:39 +0200
Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote:
> On Mon, Nov 03, 2025 at 10:18:57PM +0000, David Laight wrote:
..
> > > + [BASE64_STD] = {
> > > + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 0 - 7 */
> >
> > You need to use -1 not 0xff.
>
> Whu? The s8 type is pretty much 8-bit, care to explain the point?
I think it is clang that complains that the value is out of range.
David
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH v1 1/1] base64: Unroll the tables initialisers
2025-11-04 9:07 ` David Laight
@ 2025-11-04 9:44 ` Andy Shevchenko
0 siblings, 0 replies; 6+ messages in thread
From: Andy Shevchenko @ 2025-11-04 9:44 UTC (permalink / raw)
To: David Laight; +Cc: Andrew Morton, Guan-Chun Wu, Kuan-Wei Chiu, linux-kernel
On Tue, Nov 04, 2025 at 09:07:40AM +0000, David Laight wrote:
> On Tue, 4 Nov 2025 10:18:39 +0200
> Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote:
> > On Mon, Nov 03, 2025 at 10:18:57PM +0000, David Laight wrote:
...
> > > > + [BASE64_STD] = {
> > > > + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 0 - 7 */
> > >
> > > You need to use -1 not 0xff.
> >
> > Whu? The s8 type is pretty much 8-bit, care to explain the point?
>
> I think it is clang that complains that the value is out of range.
I use clang on daily basis to compile kernel and I definitely compiled
the proposal I sent. So, no, not this one.
--
With Best Regards,
Andy Shevchenko
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2025-11-04 9:45 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
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2025-11-03 19:05 [PATCH v1 1/1] base64: Unroll the tables initialisers Andy Shevchenko
2025-11-03 19:17 ` Andy Shevchenko
2025-11-03 22:18 ` David Laight
2025-11-04 8:18 ` Andy Shevchenko
2025-11-04 9:07 ` David Laight
2025-11-04 9:44 ` Andy Shevchenko
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