php-in-php: strcasecmp()/strncasecmp() JIT via CaseCompareJitHelper PHP — drop libc LLVM (#1492)

[PurHur]

Category

php-in-php · php-src-strict

Problem

strcasecmp()/strncasecmp() JIT still call libc via lookupFunction('strcasecmp'|'strncasecmp'); VM SSOT is VmString::strcasecmp() / VmString::strncasecmp(). Sibling strnatcmp()/strnatcasecmp() already use NaturalCompareJitHelper PHP bridges (#13535).

php-src reference

• php/php-src ext/standard/string.c — PHP_FUNCTION(strcasecmp|strncasecmp)

Repro

./script/docker-exec.sh -- php bin/vm.php -r 'var_export(strcasecmp("A","a"));'
./script/docker-exec.sh -- ./vendor/bin/phpunit --filter StrcasecmpRuntimeShrink

Scope

Path	Work
ext/standard/CaseCompareJitHelper.php	Delegate to VmString::*
lib/JIT/Builtin/StringCaseCompare.php	i8* bridge like StringNaturalCompare
ext/standard/strcasecmp.php etc.	ensureLinked + PHP bridge

Done when

• No direct libc strcasecmp/strncasecmp in ext JIT call paths after bridge install
• VM/JIT match Zend; spine sync + bootstrap VM driver probe green

Refs north star #1492

[PurHur]

claim: PHP Runtime → PHP — batch (issues #15225)

[PurHur]

Merged via #15226.

Verification

• VM: strcasecmp(\"A\",\"a\") → 0
• StrcasecmpRuntimeShrinkTest OK (4 tests)
• Inventory/spine 3772/3772; bootstrap VM driver probe OK

Shrink: JIT strcasecmp/strncasecmp now bridge through CaseCompareJitHelper → VmString instead of libc compare on the hot path.