Re: [Dwarf-Discuss] DWARF dumpers should note compressed sections

2018-08-03 Thread John DelSignore via Dwarf-Discuss
Hi Paul, TotalView recently got snagged on this with a GNU DebugFission style Split-DWARF .dwo file. A customer had things set up such that -gz=zlib was the default for their compiler, and it was producing compressed debug sections in the .dwo file, where the only hint that the section was comp

Re: [Dwarf-Discuss] modeling different address spaces

2020-07-16 Thread John DelSignore via Dwarf-Discuss
FYI, Tony Tye and his team at AMD created a DWARF Proposal for heterogeneous debugging, which is generally useful but required to debug optimized code for GPUs. It directly addresses the issue of how to model different address spaces and makes location descriptions first-class objects that can b

Re: [Dwarf-Discuss] Callable interface for Fortran "coarray" features

2020-12-30 Thread John DelSignore via Dwarf-Discuss
Hi John, The OpenMP Tools Workgroup has been discussing a very similar issue for OpenMP threads and TARGET regions (e.g.,regions offloaded to GPUs). Tony Tye at AMD (who is also a DWARF committee member) proposed a model where the compiler can generate DWARF that would tell a consumer (most lik

Re: [Dwarf-Discuss] DW_AT values unknown to me.

2021-02-17 Thread John DelSignore via Dwarf-Discuss
You probably already know this, but I'm pretty sure that "GHS" is Green Hills Software: https://www.ghs.com/products/compiler.html TotalView supported their compiler on the BBN Butterfly in the early '90s, but that predated DWARF support. Maybe someone at Green Hills can tell you what they mean

[Dwarf-Discuss] Do any of the Intel compilers still generate DW_OP_INTEL_bit_piece=0xe8?

2021-05-06 Thread John DelSignore via Dwarf-Discuss
Hi, I'm hoping someone from Intel sees this message and can definitively answer the following question: Do any of the Intel compilers still generate DW_OP_INTEL_bit_piece=0xe8? If not, do you know the last version of the compiler that did? Back in 2007, I added support for the Intel Bi-Endian

Re: [Dwarf-Discuss] data-location containing "DW_OP_push_object_address / DW_OP_deref" if the variable could be in memory or register

2021-10-27 Thread John DelSignore via Dwarf-Discuss
Hi Martin, AMD faced the same problem you are describing when generating DWARF for optimized code running on AMD GPUs. After considering several alternatives, they came up with a solution that is described in complete detail here: https://llvm.org/docs/AMDGPUDwarfExtensionsForHeterogeneousDebug

Re: [Dwarf-discuss] ISSUE: update Dwarf_Version_Numbers.md for DWARF5

2023-03-22 Thread John DelSignore via Dwarf-discuss
I agree that the web page you reference should be updated (or perhaps deleted), but you can find an up to date table in Appendix G of the DWARF 5 spec. Cheers, John D. On 3/21/23 19:03, Ben Woodard via Dwarf-discuss wrote: > It looks like > https://nam12.safelinks.protection.outlook.com/?url=ht

[Dwarf-discuss] Seeking a test program with a >4GB .debug_info section

2023-04-20 Thread John DelSignore via Dwarf-discuss
Is anyone aware of an open-source program or test program that when compiled and built on Linux x86_64, results in a .debug_info section that is greater than 4GB? I'm looking for a test program (realistic or not) that contains 32-bit DWARF CUs in a .debug_info section that is about 5GB long, or

Re: [Dwarf-discuss] Seeking a test program with a >4GB .debug_info section

2023-04-21 Thread John DelSignore via Dwarf-discuss
;s about half the size of the .debug_info in this program. On Thu, Apr 20, 2023 at 7:08 AM John DelSignore via Dwarf-discuss mailto:dwarf-discuss@lists.dwarfstd.org>> wrote: Is anyone aware of an open-source program or test program that when compiled and built on Linux x86_64, results

Re: [Dwarf-discuss] Seeking a test program with a >4GB .debug_info section

2023-04-21 Thread John DelSignore via Dwarf-discuss
s specifically doesn't push the .debug_str section as hard - it's about half the size of the .debug_info in this program. On Thu, Apr 20, 2023 at 7:08 AM John DelSignore via Dwarf-discuss mailto:dwarf-discuss@lists.dwarfstd.org>> wrote: Is anyone aware of an open-source pro

Re: [Dwarf-discuss] Seeking a test program with a >4GB .debug_info section

2023-04-21 Thread John DelSignore via Dwarf-discuss
to compile with clang) - 5 of these (could stamp them out by including this file into a few other source files & just changing the `main` function to some other name in each) This specifically doesn't push the .debug_str section as hard - it's about half the size of the .debug_info i

Re: [Dwarf-discuss] DWARF register numbers on MIPS

2023-08-16 Thread John DelSignore via Dwarf-discuss
If you can’t find it in an ABI document… You might want to look at the GDB sources, which usually contains the code to handle various targets, probably in a file named “gdb/mips*tdep.h”. Cheers, John D. From: Dwarf-discuss On Behalf Of Seva Alekseyev via Dwarf-discuss Sent: Wednesday, August

[Dwarf-discuss] gfortran / gcc on Mac puts control characters in N_SO STABS

2024-02-16 Thread John DelSignore via Dwarf-discuss
Hi, Strictly speaking, this is not a DWARF question, but it relates to DWARF because on the Mac the Mach-O NLIST/STAB symbol table is used as an index into DWARF symbols table. It's kind-of like Split-DWARF, but was invented long before Split-DWARF was added to DWARF 5. On a Mac OS 14 Sonoma M

[Dwarf-discuss] gfortran / gcc on Mac puts control characters in N_SO STABS

2024-03-13 Thread John DelSignore via Dwarf-discuss
Hi, Strictly speaking, this is not a DWARF question, but it relates to DWARF because on the Mac the Mach-O NLIST/STAB symbol table is used as an index into DWARF symbols table. It's kind-of like Split-DWARF, but was invented long before Split-DWARF was added to DWARF 5. On a Mac OS 14 Sonoma M

Re: [Dwarf-discuss] gfortran / gcc on Mac puts control characters in N_SO STABS

2024-03-13 Thread John DelSignore via Dwarf-discuss
Hi Jakub, Thanks for the reply. My answer inline below... On 3/13/24 16:29, Jakub Jelinek wrote: On Wed, Mar 13, 2024 at 07:54:03PM +, John DelSignore via Dwarf-discuss wrote: Strictly speaking, this is not a DWARF question, but it relates to DWARF because on the Mac the Mach-O NLIST

Re: [Dwarf-discuss] gfortran / gcc on Mac puts control characters in N_SO STABS

2024-03-15 Thread John DelSignore via Dwarf-discuss
Hi Adrian, Thanks for the reply. As far as I can tell, neither gcc nor gfortran produce N_SO stabs when -gdwarf-4 is used. It is the Apple ld-classic linker that is generating the N_SO stabs and inserting them into the Mach-O nlist symbol table. I believe that the linker is reading the DWARF in

Re: [Dwarf-discuss] gfortran / gcc on Mac puts control characters in N_SO STABS

2024-03-15 Thread John DelSignore via Dwarf-discuss
Thanks for looking at this. I sent a separate email with the object file attached directly to you. FWIW, using od -c to dump the string table, you can see that ^L (form feed), which is the character that ends up in the first N_SO string, immediately precedes the directory path: 00032202

Re: [Dwarf-discuss] gfortran / gcc on Mac puts control characters in N_SO STABS

2024-03-15 Thread John DelSignore via Dwarf-discuss
FWIW, when TotalView reads the DWARF, there are no control characters in the strings. Cheers, John D. On 3/15/24 13:12, Adrian Prantl wrote: On Mar 15, 2024, at 9:22 AM, John DelSignore via Dwarf-discuss <mailto:dwarf-discuss@lists.dwarfstd.org> wrote: Thanks for looking at this. I

Re: [Dwarf-discuss] Multiple inlined subroutines for a VLIW instruction bundle?

2024-10-17 Thread John DelSignore via Dwarf-discuss
Hi, I think the best way to encode the information depends on details of the processor architecture. The IA-64 (Intel Itanium architecture) had a VLIW instruction encoding with a 128-bit instruction bundle consisting of three 41-bit instruction slots per bundle plus a 5-bit template indicating

Re: [Dwarf-discuss] DW_AT_discr_value improvement

2025-01-20 Thread John DelSignore via Dwarf-discuss
Is the discriminant value always a constant? Perhaps DWARF should say, "The value of this attribute is of class constant." Table 2.3 defines attribute class constant as, "One, two, four, eight or sixteen bytes of uninterpreted data, or data encoded in the variable length format known as LEB128 (

[Dwarf-discuss] Does DWARF 5 specify which DW_LNCT content types are valid for directory entries?

2025-01-13 Thread John DelSignore via Dwarf-discuss
Hi, Section 6.2 (Line Number Information) of the DWARF 5 spec does not seem to constrain which DW_LNCT content types are valid for directory entries, or at least I couldn't find where it does. Are DW_LNCT_directory_index, DW_LNCT_timestamp, DW_LNCT_size, and/or DW_LNCT_MD5 content types valid

Re: [Dwarf-discuss] Does DWARF 5 specify which DW_LNCT content types are valid for directory entries?

2025-01-14 Thread John DelSignore via Dwarf-discuss
In-line below... On 1/13/25 20:10, David Anderson via Dwarf-discuss wrote: On 1/13/25 11:35, David Blaikie via Dwarf-discuss wrote: I guess Jon is referring to the 16th field in the header, "directories (sequence of directory names)" which uses the same encoding system (but a separate format fiel

Re: [Dwarf-discuss] Representing vtables in DWARF for downcasting

2025-04-24 Thread John DelSignore via Dwarf-discuss
On 4/23/25 22:46, Cary Coutant via Dwarf-discuss wrote: Looking at the DWARF generated by GCC (and I'm guessing LLVM does the same), I see vtable_elem_location attributes that look like this: <1b8> DW_AT_vtable_elem_location: 2 byte block: 10 0 (DW_OP_constu: 0) This is not correct DWARF!

Re: [Dwarf-discuss] DWARF on vintage CPUs

2025-05-05 Thread John DelSignore via Dwarf-discuss
Hi David, There's no standard ABI document (that I could find). You might want to look in the GDB sources on the off chance that it supported at some point. Ultimately, the thing that matters is how the compilers you are using numbers the registers. There is a decent description of the micropro

Re: [Dwarf-discuss] DWARF on vintage CPUs

2025-05-06 Thread John DelSignore via Dwarf-discuss
Inline... On 5/5/25 18:31, David Broman wrote: Thanks for the information. There are unofficial patches to both gcc and gdb to support 6809. Neither of them support DWARF. As you said, MAME could in theory just come up with a register mapping, and compiler writers (e.g., CMOC for 6809) would