Preserve full XMM registers in Windows VM wrapper#21976
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shivammathur merged 1 commit intophp:PHP-8.4from May 7, 2026
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Preserve full XMM registers in Windows VM wrapper#21976shivammathur merged 1 commit intophp:PHP-8.4from
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* PHP-8.5: Preserve full XMM registers in Windows VM wrapper (php#21976)
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* PHP-8.4: Preserve full XMM registers in Windows VM wrapper (php#21976)
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We do PGO-optimized builds for Windows releases. In our builds CI, some recorded-error tests are failing on the master branch:
https://github.com/shivammathur/php-windows-builder/actions/runs/25329578176/job/74262237899#step:6:197
https://github.com/shivammathur/php-windows-builder/actions/runs/25329578176/job/74262237943#step:6:477
After checking the trace from the build,
orig_errors_bufinzend.cwas stored in XMM6 in the PGO build, but the Windows VM wrapper was only preserving half of the XMM registers when execution re-entered the VM:php-src/Zend/zend.c
Line 1581 in b5b2c5d
So the lower half was restored correctly, but the upper half, which contained the pointer to the recorded errors array, was lost. That left
EG(errors)in an invalid state with a non-zero size but a null errors pointer.This fixes the wrapper to save and restore the full XMM6-XMM15 registers.