search for: fde

Hi All, I am trying to emit dwarf debug information for my target. By using objdump or llvm-objdump with `--dwarf=frames`, I can only see CIE (Common Information Entry) but not FDE (Frame Description Entry). Right now, my target LLVM backend only emit assembly, and let binutils do the rest. I don't know where the problem is, is there something wrong in my target LLVM backend or in the binutils? Please point me where should I look into, I will be very appreciated. Thank...

I have two JIT runs in the same process. First one runs fine. During the second JIT run the exception is thrown, and process catches SEGV after it is thrown and before it is caught. In debugger I see that crash occurs in the function 'classify_object_over_fdes' called from 'init_object' called from 'search_object' called from '_Unwind_Find_registered_FDE'. Crash occurs on invalid FDE object after several iterations over the valid FDE objects. So it looks like an invalid FDE object is attached to the valid ones. Also when...

...## CIE Code Alignment Factor .byte 120 ## CIE Data Alignment Factor .byte 16 ## CIE Return Address Column .byte 2 ## Augmentation Size .byte 16 ## LSDA Encoding = pcrel .byte 16 ## FDE Encoding = pcrel But the FDE has: .byte 0 ## Augmentation size The linker is expecting that since the CIE said there was an LSDA in each FDE that is pcrel encoded, that there would in fact be an LSDA in each FDE. But in this case, the compiler is trying to omit the LSDA...

Hi, If I type define i32 @main() gc "shadow-stack" { entry: %0 = alloca i8* %1 = call i8* @malloc(i64 1) store i8* %1, i8** %0 call void @llvm.gcroot(i8** %0, i8* null) ret i32 0 } declare i8* @malloc(i64) declare void @llvm.gcroot(i8**, i8*) nounwind in test.ll and then do > llc test.ll > gcc test.s I get the error ld: in

...know your peril and how you solved it. Stack layout: C++ code calls | | JITted C code, compiled and linked on the fly tha calls | | C++ code that throws The throw must pass through the JITted code to arrive at the catch at the top. So, the JIT must generate and install the CIE/FDE DWARF4 debug info to inform the stack unwinding virtual machine how to do it. Problems solved: 1) Do not read the DWARF docs. They give you a general idea but nobody follows it. 2) Do not try to *understand* anything. It is hopeless and you will just lose your time. 3) Try to generate EXACTLY...

...nment Factor > .byte 120 ## CIE Data Alignment Factor > .byte 16 ## CIE Return Address Column > .byte 2 ## Augmentation Size > .byte 16 ## LSDA Encoding = pcrel > .byte 16 ## FDE Encoding = pcrel > > > But the FDE has: > > .byte 0 ## Augmentation size > > The linker is expecting that since the CIE said there was an LSDA in each FDE that is pcrel encoded, that there would in fact be an LSDA in each FDE. But in this case, the...

...e(ev = 0x2000b2f8, location = "../source3/smbd/process.c:3626"), line 530 in "tevent.c" smbd_process(ev_ctx = 0x2000b2f8, msg_ctx = 0x2000b378, sock_fd = 40, interactive = @0x00000000), line 3626 in "process.c" unnamed block in smbd_accept_connection(ev = 0x2000b2f8, fde = 0x200c1598, flags = 1, private_data = 0x200c1548), line 621 in "server.c" smbd_accept_connection(ev = 0x2000b2f8, fde = 0x200c1598, flags = 1, private_data = 0x200c1548), line 621 in "server.c" unnamed block in run_events_poll(ev = 0x2000b2f8, pollrtn = 1, pfds = 0x200148a8...

Please check in an attached patch. Synopsys of the change: fixed the cleanup process of exception information in JIT. Now JIT deregisters registered by it FDE structures allowing consecutive JIT runs to succeed. Note: tools like lli should delete ExecutionEngine object and not the module. Module is deleted by ExecutionEngine. Also I am not sure if this is proper for the module to be owned by ExecutionEngine. I think they should be independently owne...

...# Personality (pcrel sdata4) .Lpersonalityref_addr1_0: .long personality-.Lpersonalityref_addr1_0 # Personality .byte 27 # LSDA Encoding (pcrel sdata4) .byte 27 # FDE Encoding (pcrel sdata4) .byte 12 # DW_CFA_def_cfa .uleb128 7 # Register .uleb128 8 # Offset .byte 144 #...

llvm[2]: Compiling DWARFDebugArangeSet.cpp for Debug+Asserts build llvm[2]: Compiling DWARFDebugAranges.cpp for Debug+Asserts build llvm[2]: Compiling DWARFDebugFrame.cpp for Debug+Asserts build /home/rkotler/llvm_trunk/lib/DebugInfo/DWARFDebugFrame.cpp:118:8: error: private field 'LinkedCIE' is not used [-We...

...*ref) { ^ C:/Users/clang/libunwind/include\unwind.h:307:28: note: previous declaration is here extern _Unwind_Reason_Code _Unwind_Backtrace(_Unwind_Trace_Fn, void *); ^ C:/Users/clang/libunwind/src/UnwindLevel1-gcc-ext.c:187:31: warning: redeclaration of '_Unwind_Find_FDE' should not add 'dllexport' attribute [-Wdll-attribute-on-redeclaration] _LIBUNWIND_EXPORT const void *_Unwind_Find_FDE(const void *pc, ^ C:/Users/clang/libunwind/include\unwind.h:344:20: note: previous declaration is here extern const void *_Unwind_Find_FD...

..._addr1_0: > .long personality-.Lpersonalityref_addr1_0 # Personality > .byte 27 > # LSDA Encoding > (pcrel sdata4) > .byte 27 > # FDE Encoding > (pcrel sdata4) > .byte 12 > # DW_CFA_def_cfa > .uleb128 7 # Register > .uleb128 8 # Offset > .byte...

...any other basic > > block in the function) you have to execute an entirely new set of CFI > instructions > > except for the common CIE part. While indeed this is not as bad, on > average, the overall > > active memory footprint will increase. > > > > Creating one FDE per basic block means that .eh_frame_hdr, an allocatable > section, > > will be bloated too. This will increase the FDE lookup time. I don’t see > .eh_frame_hdr > > being mentioned in the proposal. > > > > Maksim > > > > On 10/2/19, 12:20 PM, "Krzyszto...

...d by all llvm tools. Absolutely. We'll get to that stage, I hope. We'll need to work out if there's a way to abstract what we need from each client without slowing down or complicating any of them too much. +1. A common parser is definitely a good thing. Agree. However currently DWARFDebugFrame doesn’t have any public interface. Would it be a good first step to extract some reasonable set of accessors and back them up by unit tests? Cheers, Rafael _______________________________________________ LLVM Developers mailing list llvm-dev at lists.llvm.org<mailto:llvm-dev at lists.l...

...; .byte 120 ## CIE Data Alignment Factor >> .byte 16 ## CIE Return Address Column >> .byte 2 ## Augmentation Size >> .byte 16 ## LSDA Encoding = pcrel >> .byte 16 ## FDE Encoding = pcrel >> >> >> But the FDE has: >> >> .byte 0 ## Augmentation size >> >> The linker is expecting that since the CIE said there was an LSDA in each FDE that is pcrel encoded, that there would in fact be an LSDA in each FDE....

We would also like to clarify on the misconceptions around CFI Instructions: There are two things that need to be clarified here: 1) Extra CFI FDE entries for basic blocks does not mean more dynamic instructions are executed. In fact, they do not increase at all. Krys talked about this earlier. 2) We do deduplication of common static CFI instructions in the FDE and move it to the CIE . Hence, moving to a new basic block does not mean a comp...

...e: * Exception Handling Tables (http://www.codesourcery.com/public/cxx-abi/exceptions.pdf) This explains in detail what the table in the "__TEXT,__gcc_except_tab" section is all about. * DWARF Debugging Information Format: Version 3 (or 4) This explains the "CIE" and "FDE" tables and what their encodings means. * http://www.codesourcery.com/public/cxx-abi/abi-eh.html As Eugene pointed out, this explains what the personality function and unwind libraries do. Well, "read" might be a bad way of putting it. You should definitely familiarize yourself w...

...o 20726 failed: NT_STATUS_OBJECT_NAME_NOT_FOUND /usr/sbin/smbd: send_all_fn: messaging_send_buf to 20765 failed: NT_STATUS_OBJECT_NAME_NOT_FOUND /usr/sbin/smbd: send_all_fn: messaging_send_buf to 20750 failed: NT_STATUS_OBJECT_NAME_NOT_FOUND /usr/sbin/smbd: samba_tevent: EPOLL_CTL_DEL EBADF for fde[0x556f777743c0] mpx_fde[(nil)] fd[35] - disabling I saw that this error is always after /usr/sbin/smbd: reloading printcap cache /usr/sbin/smbd: reload status: ok /usr/sbin/smbd: pid_to_procid: messaging_dgm_get_unique failed: Aucun fichier ou dossier de ce type /usr/sbin/smbd: send_all_fn: mes...

Hi, I'm trying to get exception handling working in my compiler targetting LLVM. I've been working from the LLVM exception handling documentation (including http://llvm.org/docs/ExceptionHandling.html and http://wiki.llvm.org/HowTo:_Build_JIT_based_Exception_mechanism) and looking at g++-llvm's output. I've been trying to get a minimal test function to work, which simply invokes

..._base (encoding=encoding at entry=28 '\034', base=base at entry=0, p=p at entry=0x7fffe8a06020 <error: Cannot access memory at address 0x7fffe8a06020>, val=val at entry=0x7fffffffd6d8) at /build/gcc/src/gcc/libgcc/unwind-pe.h:252 #1 0x00007fffeba05a61 in binary_search_single_encoding_fdes (pc=0x7fffeba04426 <_Unwind_Resume+54>, ob=0x0) at /build/gcc/src/gcc/libgcc/unwind-dw2-fde.c:908 #2 search_object (ob=ob at entry=0x60400001d9d0, pc=pc at entry=0x7fffeba04426 <_Unwind_Resume+54>) at /build/gcc/src/gcc/libgcc/unwind-dw2-fde.c:977 #3 0x00007fffeba05fdd in _Unwind_Fin...