This reverts commit e2a885537f11f8d9ced1c80c2c90069ab5adeb1d. Build failures were fixed right away and reverting the original commit without the fixes breaks the build again.
The `DiagnosticOptions` class is currently intrusively
reference-counted, which makes reasoning about its lifetime very
difficult in some cases. For example, `CompilerInvocation` owns the
`DiagnosticOptions` instance (wrapped in `llvm::IntrusiveRefCntPtr`) and
only exposes an accessor returning `DiagnosticOptions &`. One would
think this gives `CompilerInvocation` exclusive ownership of the object,
but that's not the case:
```c++
void shareOwnership(CompilerInvocation &CI) {
llvm::IntrusiveRefCntPtr<DiagnosticOptions> CoOwner = &CI.getDiagnosticOptions();
// ...
}
```
This is a perfectly valid pattern that is being actually used in the
codebase.
I would like to ensure the ownership of `DiagnosticOptions` by
`CompilerInvocation` is guaranteed to be exclusive. This can be
leveraged for a copy-on-write optimization later on. This PR changes
usages of `DiagnosticOptions` across `clang`, `clang-tools-extra` and
`lldb` to not be intrusively reference-counted.
... to clarify ownership, aligning with other parameters. Using
`std::unique_ptr` encourages users to manage `createMCInstPrinter` with
a unique_ptr instead of a raw pointer, reducing the risk of memory
leaks.
* llvm-mc: fix a leak and update llvm/test/tools/llvm-mc/disassembler-options.test
* #121078 copied the llvm-mc code to CodeGenTargetMachineImpl and made
the same mistake. Fixed by 2b8cc651dca0c000ee18ec79bd5de4826156c9d6
Using unique_ptr requires #include MCInstPrinter.h in a few translation
units.
* Delete a createAsmStreamer overload I deprecated in 2024
* SystemZMCTargetDesc.cpp: rename to `createSystemZAsmStreamer` to fix
an overload conflict.
Pull Request: https://github.com/llvm/llvm-project/pull/135128
-Wa,-mmapsyms=implicit enables the alternative mapping symbol scheme
discussed at #99718.
While not conforming to the current aaelf64 ABI, the option is
invaluable for those with full control over their toolchain, no reliance
on weird relocatable files, and a strong focus on minimizing both
relocatable and executable sizes.
The option is discouraged when portability of the relocatable objects is
a concern.
https://maskray.me/blog/2024-07-21-mapping-symbols-rethinking-for-efficiency
elaborates the risk.
Pull Request: https://github.com/llvm/llvm-project/pull/104542
Also delete `AllowTemporaryLabels = true` from MCContext::reset: when
llc supports -save-temp-labels in the next change, this assignment
should be removed to support -compile-twice.
Commit 6c0665e22174d474050e85ca367424f6e02476be
(https://reviews.llvm.org/D45164) enabled certain constant expression
evaluation for `MCObjectStreamer` at parse time (e.g. `.if` directives,
see llvm/test/MC/AsmParser/assembler-expressions.s).
`getUseAssemblerInfoForParsing` was added to make `clang -c` handling
inline assembly similar to `MCAsmStreamer` (e.g. `llvm-mc -filetype=asm`),
where such expression folding (related to
`AttemptToFoldSymbolOffsetDifference`) is unavailable.
I believe this is overly conservative. We can make some parse-time
expression folding work for `clang -c` even if `clang -S` would still
report an error, a MCAsmStreamer issue (we cannot print `.if`
directives) that should not restrict the functionality of
MCObjectStreamer.
```
% cat b.cc
asm(R"(
.pushsection .text,"ax"
.globl _start; _start: ret
.if . -_start == 1
ret
.endif
.popsection
)");
% gcc -S b.cc && gcc -c b.cc
% clang -S -fno-integrated-as b.cc # succeeded
% clang -c b.cc # succeeded with this patch
% clang -S b.cc # still failed
<inline asm>:4:5: error: expected absolute expression
4 | .if . -_start == 1
| ^
1 error generated.
```
However, removing `getUseAssemblerInfoForParsing` would make
MCDwarfFrameEmitter::Emit (for .eh_frame FDE) slow (~4% compile time
regression for sqlite3.c amalgamation) due to expensive
`AttemptToFoldSymbolOffsetDifference`. For now, make
`UseAssemblerInfoForParsing` false in MCDwarfFrameEmitter::Emit.
Close#62520
Link: https://discourse.llvm.org/t/rfc-clang-assembly-object-equivalence-for-files-with-inline-assembly/78841
Pull Request: https://github.com/llvm/llvm-project/pull/91082
This reverts commit 03c53c69a367008da689f0d2940e2197eb4a955c.
This causes very large compile-time regressions in some cases,
e.g. sqlite3 at O0 regresses by 5%.
Commit 6c0665e22174d474050e85ca367424f6e02476be
(https://reviews.llvm.org/D45164) enabled certain constant expression
evaluation for `MCObjectStreamer` at parse time (e.g. `.if` directives,
see llvm/test/MC/AsmParser/assembler-expressions.s).
`getUseAssemblerInfoForParsing` was added to make `clang -c` handling
inline assembly similar to `MCAsmStreamer` (e.g. `llvm-mc -filetype=asm`),
where such expression folding (related to
`AttemptToFoldSymbolOffsetDifference`) is unavailable.
I believe this is overly conservative. We can make some parse-time
expression folding work for `clang -c` even if `clang -S` would still
report an error, a MCAsmStreamer issue (we cannot print `.if`
directives) that should not restrict the functionality of
MCObjectStreamer.
```
% cat b.cc
asm(R"(
.pushsection .text,"ax"
.globl _start; _start: ret
.if . -_start == 1
ret
.endif
.popsection
)");
% gcc -S b.cc && gcc -c b.cc
% clang -S -fno-integrated-as b.cc # succeeded
% clang -c b.cc # succeeded with this patch
% clang -S b.cc # still failed
<inline asm>:4:5: error: expected absolute expression
4 | .if . -_start == 1
| ^
1 error generated.
```
Close#62520
Link: https://discourse.llvm.org/t/rfc-clang-assembly-object-equivalence-for-files-with-inline-assembly/78841
Pull Request: https://github.com/llvm/llvm-project/pull/91082
The convention is for such MC-specific options to reside in
MCTargetOptions. However, CompressDebugSections/RelaxELFRelocations do
not follow the convention: `CompressDebugSections` is defined in both
TargetOptions and MCAsmInfo and there is forwarding complexity.
Move the option to MCTargetOptions and hereby simplify the code. Rename
the misleading RelaxELFRelocations to X86RelaxRelocations. llvm-mc
-relax-relocations and llc -x86-relax-relocations can now be unified.
This is a big refactor of the clang driver's option handling to use
the Visibility flags introduced in https://reviews.llvm.org/D157149.
There are a few distinct parts, but they can't really be split into
separate commits and still be made to compile.
1. We split out some of the flags in ClangFlags to ClangVisibility.
Note that this does not include any subtractive flags.
2. We update the Flag definitions and OptIn/OptOut constructs in
Options.td by hand.
3. We introduce and use a script, update_options_td_flags, to ease
migration of flag definitions in Options.td, and we run that on
Options.td. I intend to remove this later, but I'm committing it so
that downstream forks can use the script to simplify merging.
4. We update calls to OptTable in the clang driver, cc1as, flang, and
clangd to use the visibility APIs instead of Include/Exclude flags.
5. We deprecate the Include/Exclude APIs and add a release note.
*if you are running into conflicts with this change:*
Note that https://reviews.llvm.org/D157150 may also be the culprit and
if so it should be handled first.
The script in `clang/utils/update_options_td_flags.py` can help. Take
the downstream side of all conflicts and then run the following:
```
% cd clang/include/clang/Driver
% ../../../utils/update_options_td_flags.py Options.td > Options.td.new
% mv Options.td.new Options.td
```
This will hopefully be sufficient, please take a look at the diff.
Differential Revision: https://reviews.llvm.org/D157151
In preparation for removing the `#include "llvm/ADT/StringExtras.h"`
from the header to source file of `llvm/Support/Error.h`, first add in
all the missing includes that were previously included transitively
through this header.
Reasons for rolling forward:
- the crash reported from Chromium was fixed in D151824 (not related to this patch at all)
- since D152824 was committed, it should now be safe to roll this forward.
New change:
- add an additional _ in name check
This reverts commit 4980eead4d0b4666d53dad07afb091375b3a13a0.
Details: https://github.com/rust-lang/rust/issues/102754
The MachO format uses 2 bits to encode these personality funtions, with 0 reserved for "no-personality".
This means we can only have up to 3 personality. There are already three popular personalities: __gxx_personality_v0, __gcc_personality_v0, and __objc_personality_v0.
As a result, any system that needs custom-personality will run into a problem.
This patch implemented jyknight's proposal to simply force DWARFs for all non-canonical personality functions.
Differential Revision: https://reviews.llvm.org/D144999
For
`clang -c -g -fdebug-prefix-map=a/b=y -fdebug-prefix-map=a=x a/b/c.c`,
we apply the longest prefix substitution, but
GCC has always been picking the last applicable option (`a=x`, see
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109591).
I feel that GCC's behavior is reasonable given the convention that the last
value wins for the same option.
Before D49466, Clang appeared to apply the shortest prefix substitution,
which likely made the least sense.
Reviewed By: #debug-info, scott.linder
Differential Revision: https://reviews.llvm.org/D148975
in order to provide as much information as possible to the user. The
diagnostic will now look like for example:
error: error reading '/tmp/foo.c': Permission denied
(This addresses a FIXME from 2019, 9ef6c49baf45)
Differential revision: https://reviews.llvm.org/D146280
The forwarding header is left in place because of its use in
`polly/lib/External/isl/interface/extract_interface.cc`, but I have
added a GCC warning about the fact it is deprecated, because it is used
in `isl` from where it is included by Polly.
MC default was flipped in 2016.
CMake ENABLE_X86_RELAX_RELOCATIONS defaults to on in 2020 (c41a18cf61790fc898dcda1055c3efbf442c14c0).
It makes sense for the CodeGenOptions::RelaxELFRelocations to match, so
that most -cc1/-cc1as command lines won't have this option.
This also fixes a minor issue: -fno-plt -S will now use GOT for
__tls_get_addr calls, matching -fno-plt -c.
Avoid calling getenv in the MC layer and let the clang driver do it so
that it is reflected in the command-line as an -mllvm option.
rdar://101558354
Differential Revision: https://reviews.llvm.org/D136888
D121868 provided support for -darwin-target-variant-triple, but the
support for -darwin-target-variant-sdk-version was still missing for
cc1as. These changes build upon the previous and provides such support.
- Extracted the common code to handle -darwin-target-variant-triple and
-darwin-target-variant-sdk-version in the Darwin toolchain to a method
that can be used for both the cc1 and the cc1as job construction.
cc1as does not support some of the parameters that were provided to
cc1, so the same code cannot be used for both.
- Invoke that new common code when constructing a cc1as invocation.
- Parse the new -darwin-target-variant-sdk-version in the cc1as driver.
Apply its value to the MCObjectFileInfo to generate the right values
in the object files.
- Includes two new tests that check that cc1as uses the provided values
in -darwin-target-variant-sdk and that the Clang driver creates the
jobs with the correct arguments.
Differential Revision: https://reviews.llvm.org/D135729
"Z" was so named when we had both gABI ELFCOMPRESS_ZLIB and the legacy .zdebug support.
Now we have just one zlib format, we should use the more descriptive name.
Previously, omitting unnecessary DWARF unwinds was only done in two
cases:
* For Darwin + aarch64, if no DWARF unwind info is needed for all the
functions in a TU, then the `__eh_frame` section would be omitted
entirely. If any one function needed DWARF unwind, then MC would emit
DWARF unwind entries for all the functions in the TU.
* For watchOS, MC would omit DWARF unwind on a per-function basis, as
long as compact unwind was available for that function.
This diff makes it so that we omit DWARF unwind on a per-function basis
for Darwin + aarch64 as well. In addition, we introduce the flag
`--emit-dwarf-unwind=` which can toggle between `always`,
`no-compact-unwind` (only emit DWARF when CU cannot be emitted for a
given function), and the target platform `default`. `no-compact-unwind`
is particularly useful for newer x86_64 platforms: we don't want to omit
DWARF unwind for x86_64 in general due to possible backwards compat
issues, but we should make it possible for people to opt into this
behavior if they are only targeting newer platforms.
**Motivation:** I'm working on adding support for `__eh_frame` to LLD,
but I'm concerned that we would suffer a perf hit. Processing compact
unwind is already expensive, and that's a simpler format than EH frames.
Given that MC currently produces one EH frame entry for every compact
unwind entry, I don't think processing them will be cheap. I tried to do
something clever on LLD's end to drop the unnecessary EH frames at parse
time, but this made the code significantly more complex. So I'm looking
at fixing this at the MC level instead.
**Addendum:** It turns out that there was a latent bug in the X86
backend when `OmitDwarfIfHaveCompactUnwind` is naively enabled, which is
not too surprising given that this combination has not been heretofore
used.
For functions that have unwind info that cannot be encoded with CU, MC
would end up dropping both the compact unwind entry (OK; existing
behavior) as well as the DWARF entries (not OK). This diff fixes things
so that we emit the DWARF entry, as well as a CU entry with encoding
`UNWIND_X86_MODE_DWARF` -- this basically tells the unwinder to look for
the DWARF entry. I'm not 100% sure the `UNWIND_X86_MODE_DWARF` CU entry
is necessary, this was the simplest fix. ld64 seems to be able to handle
both the absence and presence of this CU entry. Ultimately ld64 (and
LLD) will synthesize `UNWIND_X86_MODE_DWARF` if it is absent, so there
is no impact to the final binary size.
Reviewed By: davide, lhames
Differential Revision: https://reviews.llvm.org/D122258
This patch extends cc1as to export the build version load command with
LC_VERSION_MIN_MACOSX.
This is especially important for Mac Catalyst as Mac Catalyst uses
the MacOS's compiler rt built-ins.
Differential Revision: https://reviews.llvm.org/D121868
This moves the registry higher in the LLVM library dependency stack.
Every client of the target registry needs to link against MC anyway to
actually use the target, so we might as well move this out of Support.
This allows us to ensure that Support doesn't have includes from MC/*.
Differential Revision: https://reviews.llvm.org/D111454
https://commondatastorage.googleapis.com/chromium-browser-clang/llvm-include-analysis.html
Excessive use of the <string> header has a massive impact on compile time; its most commonly included via the ErrorHandling.h header, which has to be included in many key headers, impacting many source files that have no need for std::string.
As an initial step toward removing the <string> include from ErrorHandling.h, this patch proposes to update the fatal_error_handler_t handler to just take a raw const char* instead.
The next step will be to remove the report_fatal_error std::string variant, which will involve a lot of cleanup and better use of Twine/StringRef.
Differential Revision: https://reviews.llvm.org/D111049
In preparation for passing the MCSubtargetInfo (STI) through to writeNops
so that it can use the STI in operation at the time, we need to record the
STI in operation when a MCAlignFragment may write nops as padding. The
STI is currently unused, a further patch will pass it through to
writeNops.
There are many places that can create an MCAlignFragment, in most cases
we can find out the STI in operation at the time. In a few places this
isn't possible as we are in initialisation or finalisation, or are
emitting constant pools. When possible I've tried to find the most
appropriate existing fragment to obtain the STI from, when none is
available use the per module STI.
For constant pools we don't actually need to use EmitCodeAlign as the
constant pools are data anyway so falling through into it via an
executable NOP is no better than falling through into data padding.
This is a prerequisite for D45962 which uses the STI to emit the
appropriate NOP for the STI. Which can differ per fragment.
Note that involves an interface change to InitSections. It is now
called initSections and requires a SubtargetInfo as a parameter.
Differential Revision: https://reviews.llvm.org/D45961