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<p class="MsoNormal"><span lang="EN-GB">Hello Clang- and LLVM-Experts,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">I was not sure which list is the right one, so I tried both – sorry for any inconvenient >o<<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">Lately I was working a lot with exceptions under Windows and especially with the Clang compiler. Out of curiosity I came along "Exception Handling in LLVM" and tried to understand the SJLJ exception handling. At first
glance this made total sense to me! Store important registers and when the exception occurs - restore the saved registers. Kinda like setjump and longjump but with less registers.
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">However, there are two things I really don't understand (about exception handling in general). I guess it works something like that:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">When I execute a function with a try-catch segment, as soon as I hit the try statement (Pretending I'm a Debugger or so), I would save the registerts (RSP, RIP of the catch block) on the stack I guess and keep doing what
I do. However, when I encounter an exception now - how do I know where to find my stored registers on the stack? In the mean time I could had millions of push instructions so it can't be an offset. Also I can't imagine that the stack is marked somehow - like
with a special bit pattern, risk would be to high that someone else uses that pattern. So I wonder... what is the secret behind it? Also is that the mysterious 'stack unwinding' I often heard about?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">Thank you for any tip and help in advance!<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">Kind greetings<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">Björn<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
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