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PeterK · 06 July 2018, 23:43

Hmm, what is unclear now?

The results of FACOS are perfect for round to nearest since beta2, but in Jit mode the results for round to zero are wrong now. Thus I would force rounding to nearest for FACOS to fix that.

My first fix in post #14 still checks the actual rounding mode at compile time whether it is already round to nearest. If not it takes the mode from regs.fpcr at compile time and forces it to nearest. You said, it would be better to read out regs.fpcr at execution time, which is ok, although it's very unlikely that there was a change since compile time.

So my new fix in post #16 won't check the rounding mode at compile time anymore (no if clause). Now, it always reads out regs.fpcr at execution time and forces round to nearest, even if it was already active.

The cleanup in FINTRZ should not change anything except removing dead code from the jit compilation. The current "if 0" construction leaves dead code and the "if ... else" decision is useless now. The code under "else" is always executed and thus should be called directly.

06 July 2018, 23:43	#18
PeterK Registered User Join Date: Apr 2005 Location: digital hell, Germany, after 1984, but worse Posts: 3,378	Hmm, what is unclear now? The results of FACOS are perfect for round to nearest since beta2, but in Jit mode the results for round to zero are wrong now. Thus I would force rounding to nearest for FACOS to fix that. My first fix in post #14 still checks the actual rounding mode at compile time whether it is already round to nearest. If not it takes the mode from regs.fpcr at compile time and forces it to nearest. You said, it would be better to read out regs.fpcr at execution time, which is ok, although it's very unlikely that there was a change since compile time. So my new fix in post #16 won't check the rounding mode at compile time anymore (no if clause). Now, it always reads out regs.fpcr at execution time and forces round to nearest, even if it was already active. The cleanup in FINTRZ should not change anything except removing dead code from the jit compilation. The current "if 0" construction leaves dead code and the "if ... else" decision is useless now. The code under "else" is always executed and thus should be called directly.