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AOT: fix mb_trim NestedJIT ABI (SIGSEGV/empty) leftover of #34388 #34396

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Merged
PurHur merged 1 commit into from
Aug 24, 2026
Merged

AOT: fix mb_trim NestedJIT ABI (SIGSEGV/empty) leftover of #34388 #34396

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37 changes: 22 additions & 15 deletions ext/mbstring/JitMbTrim.php
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Original file line number Diff line number Diff line change
Expand Up @@ -86,21 +86,28 @@ public static function invoke(Context $context, int $mode, string $function, arr
}
BasicBlockHelper::ensureOpenInsertBlock($context, $function.'_runtime');

$whatPtr = $context->builder->load(
$context->constantStringFromString(null === $what ? '' : $what)
);
$encPtr = $context->builder->load($context->constantStringFromString($canonical));
$i64 = $context->getTypeFromString('int64');
$whatLen = null === $what ? 0 : \strlen($what);
$resultStr = $context->builder->call(
MbTrimRuntime::trimHelper($context),
$str,
$whatPtr,
$encPtr,
$i64->constInt($mode, false),
$i64->constInt(null === $what ? 1 : 0, false),
$i64->constInt($whatLen, false)
);
if (null === $what) {
$helper = match ($mode) {
1 => MbTrimRuntime::ltrimDefaultHelper($context),
2 => MbTrimRuntime::rtrimDefaultHelper($context),
default => MbTrimRuntime::trimDefaultHelper($context),
};
$encPtr = $context->builder->load($context->constantStringFromString($canonical));
// Two-string ABI like mb_scrub — raw call; callHelper/`__value__` 1-arg SIGSEGVs.
$resultStr = $context->builder->call($helper, $str, $encPtr);
} else {
if (3 !== $mode) {
throw new \LogicException(
$function.'() with custom $characters only supports trim (both sides) in this compiler build'
);
}
$whatPtr = $context->builder->load($context->constantStringFromString($what));
$resultStr = $context->builder->call(
MbTrimRuntime::trimCharsHelper($context),
$str,
$whatPtr
);
}

return self::materializeOwnedString($context, $resultStr);
}
Expand Down
237 changes: 148 additions & 89 deletions ext/mbstring/MbTrimJitHelper.php
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Original file line number Diff line number Diff line change
Expand Up @@ -5,122 +5,181 @@
namespace PHPCompiler\ext\mbstring;

/**
* mb_trim() / mb_ltrim() / mb_rtrim() NestedJIT runtime (#34379 leftover of #5957/#23883).
* mb_trim() NestedJIT runtime (#34379 leftover of #5957/#23883).
*
* Single-function leaf kept small — NestedJIT of large UTF-8 CFGs SIGSEGVs under thin AOT.
* Handles ASCII default whitespace + U+00A0 (C2 A0), mode, and literal `$characters`.
* Broader Unicode defaults (U+1680…U+3000) stay on VM / compile-time fold.
* Public two-string leaves like {@see MbScrubJitHelper::scrubArgv} (`__string__*`).
* Private bodies: ascending for-loops only, no `break`/`continue`/strrev (those
* SIGSEGV under thin AOT when several leaves share a module).
*
* Int params: compare `$mode` / `$useDefaultWhat` directly (NestedJIT zeros copied locals —
* peer {@see MbStrwidthJitHelper}). Haystack length via isset-index; `$what` length is
* passed as `$whatLen` (NestedJIT isset on helper string params is unreliable).
*
* php-src: ext/mbstring/mbstring.c — PHP_FUNCTION(mb_trim) / mb_ltrim / mb_rtrim
* Default charset: ASCII ws + U+00A0 (C2 A0). php-src: ext/mbstring/mbstring.c
*/
final class MbTrimJitHelper
{
/**
* @param int $useDefaultWhat 1 = default trim set; 0 = use $what ('' = no trim)
*/
public static function trimArgv(
string $value,
string $what,
string $encoding,
int $mode,
int $useDefaultWhat,
int $whatLen
): string {
unset($encoding);

$doLeft = 0;
$doRight = 0;
if (1 === $mode || 3 === $mode) {
$doLeft = 1;
public static function trimDefault(string $value, string $encoding): string
{
if ('8BIT' === $encoding) {
return $value;
}
if (2 === $mode || 3 === $mode) {
$doRight = 1;

return self::trimRightBody(self::trimLeftBody($value));
}

public static function ltrimDefault(string $value, string $encoding): string
{
if ('8BIT' === $encoding) {
return $value;
}

$byteLen = 0;
while (isset($value[$byteLen])) {
$byteLen = $byteLen + 1;
if ($byteLen > 1048576) {
break;
}
return self::trimLeftBody($value);
}

public static function rtrimDefault(string $value, string $encoding): string
{
if ('8BIT' === $encoding) {
return $value;
}
if (0 === $byteLen) {
return '';

return self::trimRightBody($value);
}

public static function trimChars(string $value, string $what): string
{
if ('' === $what) {
return $value;
}

$start = 0;
if (1 === $doLeft) {
while ($start < $byteLen) {
$ch = \substr($value, $start, 1);
$w = 1;
$trim = 0;
if (1 === $useDefaultWhat) {
if (' ' === $ch || "\t" === $ch || "\n" === $ch || "\r" === $ch
|| "\0" === $ch || "\x0B" === $ch || "\x0C" === $ch || "\x85" === $ch) {
$trim = 1;
} elseif ("\xC2" === $ch && $start + 1 < $byteLen
&& "\xA0" === \substr($value, $start + 1, 1)) {
$trim = 1;
$w = 2;
return self::trimCharsRightBody(self::trimCharsLeftBody($value, $what), $what);
}

private static function trimLeftBody(string $value): string
{
$n = \strlen($value);
$out = '';
$started = 0;
$prev = '';
for ($i = 0; $i < $n; ++$i) {
$c = \substr($value, $i, 1);
$ws = 0;
if (' ' === $c || "\t" === $c || "\n" === $c || "\r" === $c
|| "\0" === $c || "\x0B" === $c) {
$ws = 1;
} elseif ("\xA0" === $c && "\xC2" === $prev) {
$ws = 1;
}
if ("\xC2" === $c) {
// Hold C2 until next byte decides NBSP vs content.
$prev = $c;
} else {
if (0 === $started) {
if (1 === $ws) {
// skip leading ws (incl trailing A0 of NBSP)
} else {
if ("\xC2" === $prev) {
$out .= $prev;
}
$started = 1;
$out .= $c;
}
} else {
$wi = 0;
while ($wi < $whatLen) {
if (\substr($what, $wi, 1) === $ch) {
$trim = 1;
break;
}
$wi = $wi + 1;
if ("\xC2" === $prev) {
$out .= $prev;
}
$out .= $c;
}
if (0 === $trim) {
break;
$prev = $c;
}
}
if ("\xC2" === $prev && 1 === $started) {
$out .= $prev;
}

return $out;
}

private static function trimRightBody(string $value): string
{
$n = \strlen($value);
$last = -1;
$prev = '';
for ($i = 0; $i < $n; ++$i) {
$c = \substr($value, $i, 1);
$ws = 0;
if (' ' === $c || "\t" === $c || "\n" === $c || "\r" === $c
|| "\0" === $c || "\x0B" === $c) {
$ws = 1;
} elseif ("\xA0" === $c && "\xC2" === $prev) {
$ws = 1;
// previous C2 was start of NBSP — retract last if it pointed at C2
if ($last === $i - 1) {
$last = $i - 2;
}
$start = $start + $w;
}
if (0 === $ws) {
$last = $i;
}
$prev = $c;
}
if ($last === $n - 1) {
return $value;
}
if ($last < 0) {
return '';
}

$end = $byteLen;
if (1 === $doRight) {
while ($end > $start) {
// Prefer NBSP (2 bytes) at end when present
$w = 1;
$ch = \substr($value, $end - 1, 1);
$trim = 0;
if (1 === $useDefaultWhat) {
if ($end - $start >= 2 && "\xC2" === \substr($value, $end - 2, 1)
&& "\xA0" === $ch) {
$trim = 1;
$w = 2;
} elseif (' ' === $ch || "\t" === $ch || "\n" === $ch || "\r" === $ch
|| "\0" === $ch || "\x0B" === $ch || "\x0C" === $ch || "\x85" === $ch) {
$trim = 1;
}
} else {
$wi = 0;
while ($wi < $whatLen) {
if (\substr($what, $wi, 1) === $ch) {
$trim = 1;
break;
}
$wi = $wi + 1;
return \substr($value, 0, $last + 1);
}

private static function trimCharsLeftBody(string $value, string $what): string
{
$n = \strlen($value);
$wlen = \strlen($what);
$out = '';
$started = 0;
for ($i = 0; $i < $n; ++$i) {
$c = \substr($value, $i, 1);
if (0 === $started) {
$hit = 0;
for ($k = 0; $k < $wlen; ++$k) {
if (\substr($what, $k, 1) === $c) {
$hit = 1;
}
}
if (0 === $trim) {
break;
if (0 === $hit) {
$started = 1;
$out .= $c;
}
$end = $end - $w;
} else {
$out .= $c;
}
}

if (0 === $start && $end === $byteLen) {
return $out;
}

private static function trimCharsRightBody(string $value, string $what): string
{
$n = \strlen($value);
$wlen = \strlen($what);
$last = -1;
for ($i = 0; $i < $n; ++$i) {
$c = \substr($value, $i, 1);
$hit = 0;
for ($k = 0; $k < $wlen; ++$k) {
if (\substr($what, $k, 1) === $c) {
$hit = 1;
}
}
if (0 === $hit) {
$last = $i;
}
}
if ($last === $n - 1) {
return $value;
}
if ($last < 0) {
return '';
}

return \substr($value, $start, $end - $start);
return \substr($value, 0, $last + 1);
}
}
38 changes: 34 additions & 4 deletions lib/JIT/Builtin/MbTrimRuntime.php
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Original file line number Diff line number Diff line change
Expand Up @@ -17,23 +17,53 @@ final class MbTrimRuntime
{
private const HELPER_PATH = '/ext/mbstring/MbTrimJitHelper.php';

private const TRIM_LOGICAL = 'PHPCompiler\\ext\\mbstring\\MbTrimJitHelper::trimArgv';
private const TRIM_DEFAULT = 'PHPCompiler\\ext\\mbstring\\MbTrimJitHelper::trimDefault';

private const LTRIM_DEFAULT = 'PHPCompiler\\ext\\mbstring\\MbTrimJitHelper::ltrimDefault';

private const RTRIM_DEFAULT = 'PHPCompiler\\ext\\mbstring\\MbTrimJitHelper::rtrimDefault';

private const TRIM_CHARS = 'PHPCompiler\\ext\\mbstring\\MbTrimJitHelper::trimChars';

/** @var list<string> */
private const COMPILED_HELPERS = [
self::TRIM_LOGICAL,
self::TRIM_DEFAULT,
self::LTRIM_DEFAULT,
self::RTRIM_DEFAULT,
self::TRIM_CHARS,
];

public static function ensureLinked(Context $context): void
{
self::ensureJitHelperCompiled($context);
}

public static function trimHelper(Context $context): LlvmFunction
public static function trimDefaultHelper(Context $context): LlvmFunction
{
self::ensureJitHelperCompiled($context);

return JitVmHelperLink::lookupCompiled($context, self::TRIM_DEFAULT, 'mb_trim');
}

public static function ltrimDefaultHelper(Context $context): LlvmFunction
{
self::ensureJitHelperCompiled($context);

return JitVmHelperLink::lookupCompiled($context, self::LTRIM_DEFAULT, 'mb_ltrim');
}

public static function rtrimDefaultHelper(Context $context): LlvmFunction
{
self::ensureJitHelperCompiled($context);

return JitVmHelperLink::lookupCompiled($context, self::RTRIM_DEFAULT, 'mb_rtrim');
}

public static function trimCharsHelper(Context $context): LlvmFunction
{
self::ensureJitHelperCompiled($context);

return JitVmHelperLink::lookupCompiled($context, self::TRIM_LOGICAL, 'mb_trim');
return JitVmHelperLink::lookupCompiled($context, self::TRIM_CHARS, 'mb_trim_chars');
}

private static function ensureJitHelperCompiled(Context $context): void
Expand Down
8 changes: 5 additions & 3 deletions test/unit/MbTrimRuntimeAotTest.php
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Expand Up @@ -35,10 +35,12 @@ public function testHelperAndLoweringPresent(): void
{
$root = dirname(__DIR__, 2);
$helper = (string) file_get_contents($root.'/ext/mbstring/MbTrimJitHelper.php');
$this->assertStringContainsString('function trimArgv', $helper);
$this->assertStringContainsString('function trimDefault', $helper);
$this->assertStringContainsString('function ltrimDefault', $helper);
$this->assertStringContainsString('function rtrimDefault', $helper);
$runtime = (string) file_get_contents($root.'/lib/JIT/Builtin/MbTrimRuntime.php');
$this->assertStringContainsString('trimHelper', $runtime);
$this->assertStringContainsString('MbTrimJitHelper::trimArgv', $runtime);
$this->assertStringContainsString('trimDefaultHelper', $runtime);
$this->assertStringContainsString('MbTrimJitHelper::trimDefault', $runtime);
$src = (string) file_get_contents($root.'/ext/mbstring/JitMbTrim.php');
$this->assertStringContainsString('MbTrimRuntime::ensureLinked', $src);
$this->assertStringNotContainsString(
Expand Down
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