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AVX2GATHER registers
See original GitHub issueHi there,
I think I found one more issue. XED disassembles C4 E2 BD 90 5C DD A2 as vpgatherdq ymm3, qword ptr [rbp+xmm3*8-0x5e], ymm8.
The SDM says:
If any pair of the index, mask, or destination registers are the same, this instruction results a UD fault.
Obviously XMM3 is not the same register as YMM3, but as they are sharing the lower 128-bits, this combination should #UD as well. The SDM is not very clear about this, but fter looking at the pseudo-code and the implications, I’m pretty sure the #UD condition refers to identical register-ids (instead of actually identical registers).
Issue Analytics
- State:
- Created 6 years ago
- Comments:5 (3 by maintainers)
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We feed the XED decoder with some random data and compare the results with Zydis.
If only one disassembler is able to decode the instruction, I take a deeper look into what could cause the issue. We think it’s only fair to report these finds back to you; improving both libraries 😄
You are correct! I changed the title.