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ptitSeb
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I don't really like the coding style (with the break inside the braces of the case...
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I can modify it.= . = |
The interpreter implements a number of SSE and AVX instructions using host floating-point operations, but did not apply the guest MXCSR.RC before performing them. As a result, directed rounding modes could produce results using the host's previous rounding mode. Add mxcsr_setround() to save the host rounding mode and temporarily apply the rounding mode selected by the guest MXCSR. Use it around the affected SSE and AVX arithmetic, horizontal, dot-product, conversion, and FMA interpreter paths, restoring the original host mode afterward. Add an interpreter regression test covering all four MXCSR rounding modes and representative scalar, packed, conversion, AVX, and FMA instructions. Force the test through the interpreter so that a dynarec path cannot hide interpreter rounding errors. Signed-off-by: Zewei Yang <yangzewei@loongson.cn>
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The interpreter implements many SSE and AVX instructions using host floating-point operations without synchronizing with the guest's MXCSR.RC.
mxcsr_setround()has been added to save the host rounding mode and temporarily apply the rounding mode selected by the guest's MXCSR (similar tox87_setround()). Regression tests for the interpreter have also been added, covering all four MXCSR rounding modes and a representative set of scalar, packed, conversion, AVX, and FMA instructions.