php-in-php: drop always-on Builtin\Output sprintf after NestedJIT snprintf migration (#32092 shape)

[PurHur]

Category

php-in-php · runtime-shrink (#1492, peer #32092 snprintf / #31706 printf)

Problem

Always-on Builtin\Output still registers libc sprintf(3) (Output.pre declare { function sprintf(char*, const char*, ...): int32; }) even though:

1. User-script sprintf() already lives in PHP (JitPrintf / SprintfSnprintfRuntime / __compiler_sprintf) — not this always-on libc row.
2. NestedJIT has only two lookupFunction('sprintf') consumers: HashTableWriteLlvm::objectPointerAsStringKey (bounded 32-byte SplObjectStorage key buffer) and ext/filter/JitFilter::jitScalarToString (native long/double → string). Both should use module-local snprintf like the php-in-php: drop always-on LibcExtern snprintf after NestedJIT module-local (#32068 shape) #32092 leaves.
3. LibcExtern already dropped always-on snprintf (php-in-php: drop always-on LibcExtern snprintf after NestedJIT module-local (#32068 shape) #32092); this leftover sprintf row in Output is the sibling still declared on every module.

Path	Today	Target
User-script sprintf()/printf()	PHP helpers (JitPrintf / SprintfSnprintfRuntime)	unchanged
Builtin\Output	always-on libc sprintf	drop declare
NestedJIT consumers	rely on always-on sprintf	LibcExtern::ensureSnprintf() + snprintf
EMBED MCJIT	__phpc_host_snprintf always-on alias	unchanged (#98 / #21109 / #21124)

php-src reference

• Userland: php/php-src ext/standard/formatted_print.c — PHP_FUNCTION(sprintf) / printf
• Filter coerce: php/php-src ext/filter/filter.c — php_filter_string scalar string conversion
• SplObjectStorage identity: php/php-src ext/spl/spl_observer.c

PHP implementation target

• lib/JIT/Builtin/Output.pre / Output.php — drop always-on libc sprintf declare
• lib/JIT/HashTableWriteLlvm.php — objectPointerAsStringKey uses ensureSnprintf() + snprintf (drop sprintf/strlen)
• ext/filter/JitFilter.php — jitScalarToString long/double uses ensureSnprintf() + __string__init
• test/unit/SprintfRuntimeShrinkTest.php — assert Output no longer addFunction('sprintf'); consumers call ensureSnprintf

Repro

./script/phpunit.sh --filter 'SprintfRuntimeShrinkTest|LibcExternDeadDeclsRuntimeShrinkTest|SnprintfRuntimeShrinkTest'

Done when

• Builtin\Output has no always-on libc sprintf declare
• No NestedJIT lookupFunction('sprintf') remains
• SplObjectStorage pointer keys and filter scalar-to-string still compile via snprintf
• php-src-strict; user-script sprintf() behavior unchanged
• __phpc_host_snprintf always-on alias remains for EMBED MCJIT

[PurHur]

claim: PHP Runtime → PHP — starting this run

[PurHur]

Merged via https://github.com/PurHur/php-compiler/pull/32111\n\nVerification run:\n- ./script/phpunit.sh --filter 'SprintfRuntimeShrinkTest|LibcExternDeadDeclsRuntimeShrinkTest|SnprintfRuntimeShrinkTest' (OK 39 tests, 615 assertions)\n- ./script/docker-exec.sh -- bash -lc 'php bin/vm.php test/repro/splobjectstorage_gethash.php && php bin/vm.php test/repro/filter_default_strip_encode.php' (expected SplObjectStorage and filter outputs)\n\nRuntime-shrink: removed always-on Builtin\Output libc sprintf declaration and routed remaining internal formatting leaves through LibcExtern::ensureSnprintf().