FEX-Emu / FEX

A fast usermode x86 and x86-64 emulator for Arm64 Linux

https://fex-emu.com

MIT License

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unittests/ASM: Fixes x87 80-bit loads on the edge of page boundaries. #4169

Open Sonicadvance1 opened 5 days ago

Sonicadvance1 commented 5 days ago

These tests ensure that FEX's x87 80-bit loadstores don't read/write past the end of the page.

Noticed we were missing testing this edge case a few days ago.

Sonicadvance1 commented 5 days ago

Nice, this immediately uncovered a bug in our implementation on the load side. Which is typically a non-problem since long double alignment is 16-byte, but the instructions for loads themselves don't care about alignment.

pmatos commented 4 days ago

LGTM. That's an interesting patch - so afaiu the problem was loading 128bit at page boundary. Well, splitting the 128bit into 64+16 bit loads creates a stronger case for

4166 . Thanks.

Sonicadvance1 commented 1 hour ago

https://www.youtube.com/watch?v=fC_q9KPczAg