TSRM: make CG, EG, SCNG and AG compile-time offsets#22287
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saves an offset load every time they're accessed
| TSRM_ALIGNED_SIZE(sizeof(zend_compiler_globals)) + | ||
| TSRM_ALIGNED_SIZE(sizeof(zend_executor_globals)) + | ||
| TSRM_ALIGNED_SIZE(sizeof(zend_php_scanner_globals)) + | ||
| TSRM_ALIGNED_SIZE(zend_mm_globals_size())); // AG size, exposed through function call |
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really unhappy about this, same issue as below:
| #if defined(__cplusplus) || defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 202311L) | ||
| # define TSRM_STATIC_ASSERT(c, m) static_assert((c), m) | ||
| #elif defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 201112L) /* C11 */ | ||
| # define TSRM_STATIC_ASSERT(c, m) _Static_assert((c), m) | ||
| #else | ||
| # define TSRM_STATIC_ASSERT(c, m) | ||
| #endif | ||
| TSRM_STATIC_ASSERT(TSRM_ALIGNED_SIZE(sizeof(tsrm_tls_entry)) == TSRM_FAST_RESERVED_BASE, | ||
| "TSRM_FAST_RESERVED_BASE must equal the tsrm_tls_entry header size"); |
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so this is a two-fold problem:
- duplicated ZEND_STATIC_ASSERT copy - tsrm can't use zend_portability, because zend_portability depends on tsrm.h
- tsrm_ls_entry size is only known in this file, not in tsrm.h consumers.
- AG size can be consumed at runtime, so it gets the last slot, but it's structurally the same problem
In C++ this would be a simple consteval function in the header, but I have no idea how to make it work in C. So I kept the definition private, but force it to the specific size it has.
| #define ZEND_CGG_DIAGNOSTIC_IGNORED_END ZEND_DIAGNOSTIC_IGNORED_END | ||
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| #if defined(__cplusplus) | ||
| #if defined(__cplusplus) || defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 202311L) |
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technically unrelated, but I didn't want to copy an incomplete definition into tsrm.c
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I'd be in favour, getting php-src and extensions to compile in extremely old environments is a pain anyway (I do rhel-7 builds for frankenphp). Should I replace this then?
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Should I replace this then?
Not yet, probably. See: https://news-web.php.net/php.internals/130714
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saves an offset load every time they're accessed
fifth split from #22231
a bit of a different approach (keep everything on the existing heap allocations, just reordered) so we don't need to work around the apache module tls surplus problem and don't need to fall back to global-exec
it's not the entire gain of the other PR, but still something. measurements without the local-exec or -mtls-size change (which will benefit on top, together they restore around half the ZTS penalty over NTS):