[lldb-dev] Layout of FXSAVE struct for x86 Architectures in LLDB

Abhishek Aggarwal via lldb-dev lldb-dev at lists.llvm.org
Thu Sep 24 02:44:19 PDT 2015

Hi all

I was looking into the file
"source/Plugins/Process/Utility/RegisterContext_x86.h" and I noticed one
thing in FXSAVE structure. The 'ftag' is defined as a 16 bit field.

However, on referring to Architecture Software Developer Manual for x86
architectures, one can see that the memory layout of the contents of FXSAVE
area has only 8 bits for 'ftag' register and rest of the 8 bits are
reserved. Is there any specific reason of keeping 'ftag' field to be 16
bits in FXSAVE structure in LLDB for x86 Architectures?

- Abhishek
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/lldb-dev/attachments/20150924/0f36669d/attachment.html>

More information about the lldb-dev mailing list