similar to: [LLVMdev] Technical details discussion for SEH

Can you clarify what you mean by "real SEH handling"? My company has me looking at this in the hopes that I can make LLVM capable of building windows drivers. If you mean "visual c++ style SEH", I'm fairly sure that isn't necessary for my purposes, but it would be nice. If you mean "something that works at all," then your concern about generalizing LLVM

Moving this month old RFC to llvmdev. Not sure why I sent this to cfe-dev in the first place... --- Based on code review discussion from John, he thinks filter expressions should be emitted into the body of the function with the try, rather than being outlined by the frontend. Instead of having the frontend create filter functions, we would use labels in place of typeinfo. The IR would look

Hi! I try to add more functionality to Win64 exception handling, based on the posted patches from Charles Davis and João Matos. But I have a question about how to map SEH handling to LLVM IR. The basic structure of SEH in C is as follows: __try { // Do something. } __except (filter(GetExceptionCode(), GetExceptionInformation())) { // Handle exception } How to

Hi Kai, > I try to add more functionality to Win64 exception handling, based on the posted > patches from Charles Davis and João Matos. > > But I have a question about how to map SEH handling to LLVM IR. are you sure you don't mean: map LLVM IR to SEH? I.e. are you talking about how to implement LLVM's "dwarf" exception handling intrinsics and landingpad

On 30/01/2014 22:57, Daniel Berlin wrote: > On Thu, Jan 30, 2014 at 2:34 PM, Alp Toker <alp at nuanti.com> wrote: >> On 30/01/2014 22:06, Daniel Berlin wrote: >>> Actually, the policy actually says the right thing, you removed a >>> sentence, which says: >>> "Please contact the oversight group for more details." >> >> To be clear, I

Hi Reid, I’ve been following your proposal, and I’d be interested in helping out if I can. My main interest right now is in enabling C++ exception handling in clang for native (i.e. not mingw/cygwin) Windows targets (both 32-bit and 64-bit), but if I understand things correctly that will be closely related to your SEH work under the hood. I’m still trying to get up to speed on what is and is

Hi, I apologize if I'm posting this to the wrong list; if this is the case, please let me know. For some time now, I've been trying to get SEH exception handling to work in LLVM MCJIT (x64). While reading up on LLVM 3.8, I decided to pick it up again, because a lot has changed which simplifies things greatly. As a toy project, I'm attempting to catch an exception that's thrown

Hi, Per Reid’s feedback, I have separated two SEH missing features. This thread now is only focusing on _local_unwind(), Jumping out of _finally. The design is documented in Wiki here: https://github.com/tentzen/llvm-project/wiki/Windows-SEH:-Local_Unwind-(aka:-Jumping-Out-of-_Finally) The implementation can be seen here:

Hi, all, The intend of this thread is to complete the support for Windows SEH. Currently there are two major missing features: Jumping out of a _finally and Hardware exception handling. The document below is my proposed design and implementation to fully support SEH on LLVM. I have completely implemented this design on a branch in repo:

I don’t know much about SEH and haven’t had time to really dig into this, but the idea of outlining functions that need to know about the frame layout sounds a bit scary. Is it really necessary? I’m wondering if you can treat the cleanups and filter functions as portions of the same function, instead of outlining them to separate functions. Can you arrange to set up the base pointer on entry to

Hi Reid, I saw your patch but haven’t looked closely at it yet. I do have a work in progress for the outlining. I expect to have something ready to share pretty soon, hopefully by the end of the week. It won’t be ready for primetime, as it’s making a whole lot of assumptions about the structure of the IR, but I think it will work with a sample IR file based on what you posted in your earlier

I don’t really have a good enough feeling for the landingpad syntax yet to comment on the most natural way to extend it yet, but creating a synthetic cleanup function to call from the personality function is what I was thinking. With the current (trunk +/- a couple of weeks) clang, compiling for an “x86_64-pc-windows-msvc” target, I’m seeing a landingpad that looks like this: lpad:

Hi, This is a spin-off of previous Windows SEH RFC below. This RFC only focus on supporting HW Exception Handling. A detailed implementation can be seen in here: https://github.com/tentzen/llvm-project/commit/8a2421c274b683051e456cbe12c177e3b934fb5e It passes all MSVC SEH suite (excluding those with “Jumping out of _finally” ( _Local_Unwind)). Thanks, --Ten **** The rules for C code: ****

In the past people in #llvm suggested to me I should use landing pads instead of seh when it comes to Windows unless i really need seh. Looking at what gets generated win64 -gnu does use seh but calls the landing pad somehow, while win32 doesn't at all. It looks to me a custom win64 landing pad personality can also deal with things like Access Violation. Is there a way to make win32 also

Hello everyone, I was wondering what is the status regarding exceptions for the windows-msvc target? The corresponding part of the documentation (llvm/decs/ExceptionHandling.rst) hasn't been updated since 2015, was there any progress since? This is most likely known, but there's significant divergence between the behavior of MSVC cl.exe and clang-cl.exe: Consider: void crash() {

On Mon, May 18, 2015 at 11:48 AM, Steve Cheng <steve.ckp at gmail.com> wrote: > On 2015-05-18 13:32:54 -0400, Reid Kleckner said: > >> >> Right, doing our own personality function is possible, but still has half >> the challenge of using __CxxFrameHandler3, and introduces a new runtime >> dependency that isn't there currently. Given that it won't save

Hi, Eli, Why are you under the impression that threw_exception() will not be called if optimizations are enabled? I don’t know if the -EHa Spec is clearly described in MSFT Webs. At least this proposal has described the rules for both C & C++ code. The very first rule clearly said that “no exception can move in or out of _try region., i.e., no potential faulty instruction can be moved

https://llvm.org/docs/ExceptionHandling.html#wineh > No variables live in to or out of the funclet can be allocated in registers. I don't think this is quite true. though it might be a useful simplification. Obviously it is true for volatile registers, but I believe the funclet receives a CONTEXT with the nonvolatiles restored. Obviously cumbersome to access, but it lets you enregister

Is this example what you had in mind? void f() { int *p = get_p(); use_p(p); try { may_throw(p); } catch (int) { // don't need p } use_p(p); } The idea is that because p is not modified or used within the catch region (the funclet), it can live in a callee-saved register across the whole function. That is true, it is possible, but I don't think it fits very well in

As stated in the design paragraph, this design does not intend to model precise CFG at instruction level since it’s complicated and unnecessary. As long as we comply C and C++ rules listed below, we achieve -EHa semantic. There is NO need to precisely model HW exception control flow at instruction-level. Your example about memcpy() is just a bug in current implementation. I will fix it so that