Proposed alternative to D105338.
This is ugly, but short-term I think it's the best way forward: first,
let's formalize the hacks into a coherent model. Then we can consider
extensions of that model (we could have different flavors of volatile
with different rules).
Differential Revision: https://reviews.llvm.org/D106309
* ELF supports `nodeduplicate`.
* ELF calls the concept "section group". `GRP_COMDAT` emulates the PE COMDAT deduplication feature.
* "COMDAT group" is an ELF term. Avoid it for PE/COFF.
* WebAssembly supports comdat but only supports the `any` selection kind. https://bugs.llvm.org/show_bug.cgi?id=50531
* A comdat must be included or omitted as a unit. Both the compiler and the linker must obey this rule.
* A global object can be a member of at most one comdat.
* COFF requires a non-local linkage for non-`nodeduplicate` selection kinds.
* llvm.global_ctors/.llvm.global_dtors: if the third field is used on ELF, it must reference a global variable or function in a comdat
Reviewed By: rnk
Differential Revision: https://reviews.llvm.org/D106300
In the textual format, `noduplicates` means no COMDAT/section group
deduplication is performed. Therefore, if both sets of sections are retained, and
they happen to define strong external symbols with the same names,
there will be a duplicate definition linker error.
In PE/COFF, the selection kind lowers to `IMAGE_COMDAT_SELECT_NODUPLICATES`.
The name describes the corollary instead of the immediate semantics. The name
can cause confusion to other binary formats (ELF, wasm) which have implemented/
want to implement the "no deduplication" selection kind. Rename it to be clearer.
Reviewed By: rnk
Differential Revision: https://reviews.llvm.org/D106319
As discussed on D105251, currently the compiler does not support
multiple metadata attachments on instructions having the same
identifier, whereas it does for global objects. Note this in the
Language Reference manual for clarity.
See D105251 for discussions of history behind this divergence, and the
complexities and possible approaches of adding this support to
instructions in the future.
Differential Revision: https://reviews.llvm.org/D106304
Use the elementtype attribute introduced in D105407 for the
llvm.preserve.array/struct.index intrinsics. It carries the
element type of the GEP these intrinsics effectively encode.
This patch:
* Adds a verifier check that the attribute is required.
* Adds it in the IRBuilder methods for these intrinsics.
* Autoupgrades old bitcode without the attribute.
* Updates the lowering code to use the attribute rather than
the pointer element type.
* Updates lots of tests to specify the attribute.
* Adds -force-opaque-pointers to the intrinsic-array.ll test
to demonstrate they work now.
https://reviews.llvm.org/D106184
For example, I need this lately in my CI config:
LIT_XFAIL_NOT='libomptarget :: nvptx64-nvidia-cuda :: unified_shared_memory/api.c'
That test specifies an XFAIL directive, but I get an XPASS result.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D106022
We can build it with -Werror=global-constructors now. This helps
in situation where libSupport is embedded as a shared library,
potential with dlopen/dlclose scenario, and when command-line
parsing or other facilities may not be involved. Avoiding the
implicit construction of these cl::opt can avoid double-registration
issues and other kind of behavior.
Reviewed By: lattner, jpienaar
Differential Revision: https://reviews.llvm.org/D105959
We can build it with -Werror=global-constructors now. This helps
in situation where libSupport is embedded as a shared library,
potential with dlopen/dlclose scenario, and when command-line
parsing or other facilities may not be involved. Avoiding the
implicit construction of these cl::opt can avoid double-registration
issues and other kind of behavior.
Reviewed By: lattner, jpienaar
Differential Revision: https://reviews.llvm.org/D105959
We can build it with -Werror=global-constructors now. This helps
in situation where libSupport is embedded as a shared library,
potential with dlopen/dlclose scenario, and when command-line
parsing or other facilities may not be involved. Avoiding the
implicit construction of these cl::opt can avoid double-registration
issues and other kind of behavior.
Reviewed By: lattner, jpienaar
Differential Revision: https://reviews.llvm.org/D105959
This adds an elementtype(<ty>) attribute, which can be used to
attach an element type to a pointer typed argument. It is similar
to byval/byref in purpose, but unlike those does not carry any
specific semantics by itself. However, certain intrinsics may
require it and interpret it in specific ways.
The in-tree use cases for this that I'm currently aware of are:
call ptr @llvm.preserve.array.access.index.p0.p0(ptr elementtype(%ty) %base, i32 %dim, i32 %index)
call ptr @llvm.preserve.struct.access.index.p0.p0(ptr elementtype(%ty) %base, i32 %gep_index, i32 %di_index)
call token @llvm.experimental.gc.statepoint.p0(i64 0, i32 0, ptr elementtype(void ()) @foo, i32 0, i32 0, i32 0, i32 0, ptr addrspace(1) %obj)
Notably, the gc.statepoint case needs a function as element type,
in which case the workaround of adding a separate %ty undef
argument would not work, as arguments cannot be unsized.
Differential Revision: https://reviews.llvm.org/D105407
This breaks out some (more) common llvm-specific
variables. Controlling the subprojects and target architectures, along
with clues about restricting build parallelism when linking. 'more
common' is somewhat subjective, of course.
Differential Revision: https://reviews.llvm.org/D105822
The CMake community Wiki has been moved to the [[ https://gitlab.kitware.com/cmake/community/wikis/home | Kitware GitLab Instance ]].
Also, the original anchor for `Information how to set up various cross compiling toolchains` section might not work as expected. The original content is now being collapsed, so browser won't navigate to the right section directly.
Hence, I think it might be better to provide the section name instead of `this section` with link to help readers find the right section by themselves.
Reviewed By: void
Differential Revision: https://reviews.llvm.org/D104996
This new MIR pass removes redundant DBG_VALUEs.
After the register allocator is done, more precisely, after
the Virtual Register Rewriter, we end up having duplicated
DBG_VALUEs, since some virtual registers are being rewritten
into the same physical register as some of existing DBG_VALUEs.
Each DBG_VALUE should indicate (at least before the LiveDebugValues)
variables assignment, but it is being clobbered for function
parameters during the SelectionDAG since it generates new DBG_VALUEs
after COPY instructions, even though the parameter has no assignment.
For example, if we had a DBG_VALUE $regX as an entry debug value
representing the parameter, and a COPY and after the COPY,
DBG_VALUE $virt_reg, and after the virtregrewrite the $virt_reg gets
rewritten into $regX, we'd end up having redundant DBG_VALUE.
This breaks the definition of the DBG_VALUE since some analysis passes
might be built on top of that premise..., and this patch tries to fix
the MIR with the respect to that.
This first patch performs bacward scan, by trying to detect a sequence of
consecutive DBG_VALUEs, and to remove all DBG_VALUEs describing one
variable but the last one:
For example:
(1) DBG_VALUE $edi, !"var1", ...
(2) DBG_VALUE $esi, !"var2", ...
(3) DBG_VALUE $edi, !"var1", ...
...
in this case, we can remove (1).
By combining the forward scan that will be introduced in the next patch
(from this stack), by inspecting the statistics, the RemoveRedundantDebugValues
removes 15032 instructions by using gdb-7.11 as a testbed.
Differential Revision: https://reviews.llvm.org/D105279
Currently, if target of s_branch instruction is in another section, it will fail with the error of undefined label. Although in this case, the label is not undefined but present in another section. This patch tries to handle this issue. So while handling fixup_si_sopp_br fixup in getRelocType, if the target label is undefined we issue an error as before. If it is defined, a new relocation type R_AMDGPU_REL16 is returned.
This issue has been reported in https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100181 and https://bugs.llvm.org/show_bug.cgi?id=45887. Before https://reviews.llvm.org/D79943, we used to get an crash for this scenario. The crash is fixed now but the we still get an undefined label error. Jumps to other section can arise with hold/cold splitting.
A patch to handle the relocation in lld will follow shortly.
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D105760
Users should generally observe no difference as long as they don't use
unintended option forms. Behavior changes:
* `-t=d` is removed. Use `-t d` instead.
* `--demangle=false` and `--demangle=0` cannot be used. Omit the option or use `--no-demangle`. Other flag-style options don't have `--no-` forms.
* `--help-list` is removed. This is a `cl::` specific option.
* llvm-readobj now supports grouped short options as well.
* `--color` is removed. This is generally not useful (only apply to errors/warnings) but was inherited from Support.
Some adjustment to the canonical forms
(usually from GNU readelf; currently llvm-readobj has too many redundant aliases):
* --dyn-syms is canonical. --dyn-symbols is a hidden alias
* --file-header is canonical. --file-headers is a hidden alias
* --histogram is canonical. --elf-hash-histogram is a hidden alias
* --relocs is canonical. --relocations is a hidden alias
* --section-groups is canonical. --elf-section-groups is a hidden alias
OptTable avoids global option collision if we decide to support multiplexing for binary utilities.
* Most one-dash long options are still supported. `-dt, -sd, -st, -sr` are dropped due to their conflict with grouped short options.
* `--section-mapping=false` (D57365) is strange but is kept for now.
* Many `cl::opt` variables were unnecessarily external. I added `static` whenever appropriate.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D105532
In review discussion on D104322, Eli and Roman quite reasonable raised concerns about the LangRef not really providing a precise definition for inttoptr/ptrtoint on non-integral types. These had previously been disallowed, but I'd pragmatically allowed them in ac81cb7e6. This is my attempt to improve the situation.
Differential Revision: https://reviews.llvm.org/D104547
The documentation for the AMDGPU assembler's examples don't show the
.args section, which, if ommitted, will cause arguments to silently
not be passed into the kernel. This commit fixes this issue.
Reviewed By: #amdgpu, scott.linder
Differential Revision: https://reviews.llvm.org/D105222
Part of https://lists.llvm.org/pipermail/llvm-dev/2021-July/151622.html
"Binary utilities: switch command line parsing from llvm::cl to OptTable"
* `--totals=false` and `--totals=0` cannot be used. Omit the option.
* `--help-list` is removed. This is a `cl::` specific option.
OptTable avoids global option collision if we decide to support multiplexing for binary utilities.
Note: because the tool is simple, and its long options are uncommon, I just drop
the one-dash forms except `-arch <value>` (Darwin style).
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D105598
Similar to D104889. The tool is very simple and its long options are uncommon,
so just drop the one-dash form in this patch.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D105605
A change in the API happened as per http://reviews.llvm.org/D89463
(latest related commit b9e2b59680ad1bbfd2b9110b3ebf3d2b22cad51b)
but the RST documentation was not updated to match this at that time.
Notably, a global variable with the metadata should generally not be referenced
by a function function. E.g. -fstack-size-section usage is fine, but
-fsanitize-coverage= used to have a linker GC problem (fixed by D97430).
Reviewed By: eugenis
Differential Revision: https://reviews.llvm.org/D104933
Part of https://lists.llvm.org/pipermail/llvm-dev/2021-July/151622.html
"Binary utilities: switch command line parsing from llvm::cl to OptTable"
Users should generally observe no difference as long as they only use intended
option forms. Behavior changes:
* `-t=d` is removed. Use `-t d` instead.
* `--demangle=0` cannot be used. Omit the option or use `--no-demangle` instead.
* `--help-list` is removed. This is a `cl::` specific option.
Note:
* `-t` diagnostic gets improved.
* This patch avoids cl::opt collision if we decide to support multiplexing for binary utilities
* One-dash long options are still supported.
* The `-s` collision (`-s segment section` for Mach-O) is unfortunate. `-s` means `--print-armap` in GNU nm.
* This patch removes the last `cl::multi_val` use case from the `llvm/lib/Support/CommandLine.cpp` library
`-M` (`--print-armap`), `-U` (`--defined-only`), and `-W` (`--no-weak`)
are now deprecated. They could conflict with future GNU nm options.
(--print-armap has an existing alias -s, so GNU will unlikely add a new one.
--no-weak (not in GNU nm) is rarely used anyway.)
`--just-symbol-name` is now deprecated in favor of
`--format=just-symbols` and `-j`.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D105330
Set informational fields in the .shader_functions table.
Also correct the documentation, .scratch_memory_size and .lds_size are
integers.
Differential Revision: https://reviews.llvm.org/D105116
Some behavior changes:
* `-t=d` is removed. Use `-t d` instead.
* one-dash long options like `-all` are supported. Use `--all` instead.
* `--all=0` or `--all=false` cannot be used. (Note: `--all` is silently ignored anyway)
* `--help-list` is removed. This is a `cl::` specific option.
Nobody is likely leveraging any of the above.
Advantages:
* `-t` diagnostic gets improved.
* in the absence of `HideUnrelatedOptions`, `--help` will not list unrelated options if linking against libLLVM-13git.so or linker GC is not used.
* Decrease the probability of cl::opt collision if we do decide to support multiplexing
Note: because the tool is so simple, used more for forensics instead of a building
tool, and its long options are unlikely used in one-dash form, I just drop the
one-dash form in this patch.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D104889
Summary: The patch adds the StringTable dumping to
llvm-readobj. Currently only XCOFF is supported.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D104613
This reverts commit 8cd35ad854ab4458fd509447359066ea3578b494.
It breaks `TestMembersAndLocalsWithSameName.py` on GreenDragon and
Mikael Holmén points out in D104827 that bitcode files created with the
patch cannot be parsed with binaries built before it.
While this should not matter for most architectures (where the program
address space is 0), it is important for CHERI (and therefore Arm Morello).
We use address space 200 for all of our code pointers and without this
change we assert in the SelectionDAG handling of BlockAddress nodes.
It is also useful for AVR: previously programs targeting
AVR that attempt to read their own machine code
via a pointer to a label would instead read from RAM
using a pointer relative to the the start of program flash.
Reviewed By: dylanmckay, theraven
Differential Revision: https://reviews.llvm.org/D48803
The new documentation entry gives an example use case from
libomptarget.
Reviewed By: yln, jhenderson, davezarzycki
Differential Revision: https://reviews.llvm.org/D105208
