similar to: [LLVMdev] MCJIT Mach-O JIT debugging

I didn't get to work on this more last week, but I'll look at incorporating that suggestion. The other question of course is how to do this in LLDB. Right, now what I'm doing is going through and adjusting the load address of every leaf in the section tree. That basically works and gets me backtraces with the correct function names and the ability to set breakpoints at functions in

We don't currently apply any relocations (that I know of) for debug info in LLDB. > On Jun 2, 2014, at 12:35 PM, Keno Fischer <kfischer at college.harvard.edu> wrote: > > I think I'm getting closer. The debug_info section is being relocated correctly (I think): > > 0x00000000: Compile Unit: length = 0x00000045 version = 0x0003 abbr_offset = 0x00000000 addr_size =

I am wondering how the following issue was handled for libLTO? We have a working patch to implement the FSF gcc LTO on darwin which now passes all of the liblto testsuite but are seeing linker issues with larger programs like aermod... as -arch x86_64 -force_cpusubtype_ALL -o aermod.o aermod.s /usr/bin/ld -dynamic -arch x86_64 -macosx_version_min 10.6.3 -weak_reference_mismatches

This is probably a problem with having too many sections. There are a few places where mach-o has a limit on the number of sections. For instance the n_sect field of the nlist record is one byte. So any symbol in a section past the 255th section wraps around and shows up with the wrong n_sect number. -Nick On Apr 29, 2010, at 6:19 AM, Jack Howarth wrote: > I am wondering how the

Nick, Steven believes that aermod certainly could have more than 255 sections. Is there a particular approach that would be recommended for working around such a problem? Short of reducing the actual number of sections? It is suggested that this is why -ffunction-sections doesn't work on darwin and that one possible solution is to embed an 'ar' format section in the .gnu.lto

I looked into this further. ld64 has a macho_nlist abstraction over the various underlying nlist structures [1]. On x86-64, the P::getP referenced in n_value will resolve to [2], which in turn goes to [3], which calls OSReadLittleInt64. On a little endian machine, OSReadLittleEndian just calls _OSReadInt64 [4], which in turn does a pointer arithmetic and cast and then dereferences the pointer [5].

When I make a simple test program and call abort() and use LLDB to debug it, it has address-to-line mapping. If I then delete the .o file and run LLDB again, it loses the address-to-line mapping. So there must be DWARF info, or otherwise address-to-line info in the .o file. I'm parsing the MACH-O executable, which has a LC_SYMTAB entry, and one of the entries is the file path of the .o file.

I have written a few different summary functions. I want to calculate the statistics by groups and I am having trouble getting the output as a dataframe. I have attached one example with a small dataset that calculates summary stats and percentiles, I have others that calculate upper confidence limits etc. I would like the output to be converted to a dataframe with one of the columns as the

As part of our work on LLD for Mach-O, we’ve observed that the object files produced by LLVM don’t always have aligned nlist_64 entries. For context, nlist_64 is the 64-bit symbol table entry structure for Mach-O, and the symbol table is an array of nlist_64 entries. nlist_64 has an 8 byte member, so it should be 8-byte aligned, but we’ve seen object files where the symbol table only has a 4-byte

A few weeks ago I did a source upgrade from 6.2 to 7-STABLE. I didn't "make delete-old" so a bunch of old libraries and such were left lying around causing problems when I rebuilt all my ports. I'd read about some recent improvements to DDB and SCHED_ULE in 7-STABLE, and it's a miserable snowy weekend in Seattle right now, so I decided I'd take this opportunity to

Hi Keno, I am talking about runtime. The performance of the generated machine code. Not the time it takes to lower the IR to machine code. We typically only JIT once (taking a few secs) and then run the generated machine code for hours. So the JIT time (IR -> machine code) doesn't impact us. Cheers Morten On 05/02/16 15:58, Keno Fischer wrote: > Actually, reading over all of this

Hi Keno, The part that scares me a bit is > and then adjust the other methods to not > bail out two quickly when encountering a weak symbol. I would very much appreciate if you could implement this; I don't have enough knowledge of the MCJIT nor llvm CodeGen internals... I will happily try it out and provide you with feedback, though! :-) Thank you *so* much for your fast reaction!

On 22 May 2013 12:30, Kaylor, Andrew <andrew.kaylor at intel.com> wrote: > To clarify, MCJIT currently has no GOT support whatsoever for ELF with x86-64 and ARM (and probably others). No, I added a bare minimal to get EH working... > My experimental patch was meant as an attempt to get TLS working with static relocation model and small code model. It's the combination of these

Hi Keno, Could you give a short high-level overview of the way Julia works now with MCJIT instead the JIT: What I gather so far... * Compiled IR functions are emitted to a shadow module. * Any used function is cloned into its own new module and the module is added to MCJIT. * Called functions or globalvars are only declared in that module. * Modules are never removed meaning "old"

Hi Everyone, If you're JITing with LLVM and haven't made the switch to MCJIT already, now is the time. As per discussions on the mailing list and at the last dev meeting, LLVM 3.5 will be the last release to support the old JIT infrastructure. Now that LLVM 3.5 has branched, we plan to start removing the old JIT from the mainline. If you're looking for help in making the switch, Andy

On Fri, May 22, 2015 at 4:14 PM, Keno Fischer <kfischer at college.harvard.edu> wrote: > This might be related to GOT relocations. I rewrote that part of > RuntimeDyldELFbecause I was seeing this issue. Have you tried trunk? > I didn't notice that you were running 3.5 the first time I read this. Keno's diagnosis is very likely to be correct. You should try trunk if

Hi Dale, I don't think that Keno's rewrite is applicable for a bug fix release. We have, in the last year, moved to having some dot releases for our older releases, but these are definitely bug fix only and low risk as we don't want to break anything new. The release documentation is located here: http://llvm.org/docs/HowToReleaseLLVM.html for future reference. There's no

Hi Morten, Something else just occurred to me: can you share your EngineBuilder configuration lines? (http://llvm.org/docs/doxygen/html/classllvm_1_1EngineBuilder.html) In particular - are you explicitly setting the optimization level? The old JIT may have had a different default. - Lang. Sent from my iPad > On Feb 4, 2016, at 10:54 PM, Jim Grosbach via llvm-dev <llvm-dev at

Hi, I'm finally moving cling to MCJIT - and MCJIT is wonderful! So far I only ran into this issue: $ cat linkonceodr.cxx extern "C" int printf(const char*,...); template <class T> struct StaticStuff { static T s_data; }; template <class T> T StaticStuff<T>::s_data = 42; int compareAddr(int* mcjit); #ifdef BUILD_SHARED int compareAddr(int* mcjit) { if (mcjit

Hi Keno, Thanks for the fast ISel suggestion. Here are the results (for a small but representational run): LLVM 3.5.2 (old JIT): 4m44s LLVM 3.7.1 (MCJit) no fast ISel: 7m31s LLVM 3.7.1 (MCJit) fast ISel: 7m39s So not much of a difference unfortunately. On 05/02/16 11:05, Keno Fischer wrote: > Yes, unfortunately, this is very much known. Over in the julia > project, we've recently