[RV64_DYNAREC] Fixed SBB16/SBB32 scratch register clobbering in flag calculation#3889
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ksco
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May 24, 2026
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LGTM, thanks. May I ask how did you find these? |
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I found these issues while running some benchmarks on an XThead-related chip. |
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Fixed SBB16/SBB32 SET_FLAGS_LTZ clobbering ~op1 in RV64 dynarec.
In emit_sbb16 and emit_sbb32, SET_FLAGS_LTZ used s5 as a scratch register, but s5 holds ~op1 which is needed later by CALC_SUB_FLAGS for borrow chain calculation. This caused CF and AF to be computed incorrectly.
Changed SET_FLAGS_LTZ scratch parameters from (s4, s5) to (s3, s4) to avoid clobbering ~op1.
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