Compile negated conditions as inverted jumps - #23292
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'if (!$x)', while/do-while conditions and ternaries with a top-level '!' emitted a BOOL_NOT into a temporary followed by JMPZ/JMPNZ - two dispatches and a TMP per evaluation, since without the opcache optimizer nothing rewrites it. Strip '!' layers in the condition and flip the jump opcode instead; both paths evaluate the operand with i_zend_is_true, so behavior including undefined-variable warnings is identical. This also lets comparisons under '!' fuse with the jump (smart branch), which BOOL_NOT previously prevented. Adjusts two opcode-dump tests for the changed temporary numbering.
staabm
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in ondrejmirtes/php-src
Aug 15, 2026
'if (!$x)', while/do-while conditions and ternaries with a top-level '!' emitted a BOOL_NOT into a temporary followed by JMPZ/JMPNZ - two dispatches and a TMP per evaluation, since without the opcache optimizer nothing rewrites it. Strip '!' layers in the condition and flip the jump opcode instead; both paths evaluate the operand with i_zend_is_true, so behavior including undefined-variable warnings is identical. This also lets comparisons under '!' fuse with the jump (smart branch), which BOOL_NOT previously prevented. Adjusts two opcode-dump tests for the changed temporary numbering.
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disclaimer: this change was generated by claude opus. I have little experience with php-src development
'if (!$x)', while/do-while conditions and ternaries with a top-level '!' emitted a BOOL_NOT into a temporary followed by JMPZ/JMPNZ - two dispatches and a TMP per evaluation, since without the opcache optimizer nothing rewrites it. Strip '!' layers in the condition and flip the jump opcode instead; both paths evaluate the operand with i_zend_is_true, so behavior including undefined-variable warnings is identical. This also lets comparisons under '!' fuse with the jump (smart branch), which BOOL_NOT previously prevented.
Adjusts two opcode-dump tests for the changed temporary numbering.
note the improved
*_negatedvariantsafter PR
before PR
using negated_conditions_repro.php