112 Commits

Author SHA1 Message Date
Abid Qadeer
04aa5a88d1
[OMPIRBuilder] Don't discard the debug record from entry block. (#135161)
When we get a function back from `CodeExtractor`, we discard its entry
block after coping its instructions into the entry block we prepared.
While copying the instructions, the terminator is discarded for obvious
reasons. But if there were some debug values attached to the terminator,
those are useful and needs to be copied.
2025-04-30 10:25:35 +01:00
Tom Eccles
f7daa9d302
[mlir][OpenMP] fix crash outlining infinite loop (#129872)
Previously an extra block was created by splitting the previous exit
block. This produced incorrect results when the outlined region
statically never terminated because then there wouldn't be a valid exit
block for the outlined region, this caused this newly added block to
have an incoming edge from outside of the outlining region, which caused
outlining to fail.

So far as I can tell this extra block no longer serves any purpose. The
comment says it is supposed to collate multiple control flow edges into
one place, but the code as it is now does not achieve this. In fact, as
can be seen from the changes to lit tests, this block was not actually
outlined in the end. This is because there are actually two code
extractors: one in the callback for creating a parallel op which is used
to find what the input/output variables are (which does have this block
added to it), and another one which actually does the outlining (which
this block was not added to).

Tested with the gfortran and fujitsu test suites.

Fixes #112884
2025-03-07 11:02:52 +00:00
Johannes Doerfert
3c8efd7928
[OpenMP] Ensure the actual kernel is annotated with launch bounds (#99927)
In debug mode there is a wrapper (the kernel) around the function in
which we generate the kernel code. We worked around this before to get
the correct kernel name, but now we really distinguish both to attach
the launch bounds to the kernel, not the inner function.
2024-07-23 09:02:47 -07:00
Stephen Tozer
094572701d
[RemoveDIs] Print IR with debug records by default (#91724)
This patch makes the final major change of the RemoveDIs project, changing the
default IR output from debug intrinsics to debug records. This is expected to
break a large number of tests: every single one that tests for uses or
declarations of debug intrinsics and does not explicitly disable writing
records. 

If this patch has broken your downstream tests (or upstream tests on a
configuration I wasn't able to run):
1. If you need to immediately unblock a build, pass
`--write-experimental-debuginfo=false` to LLVM's option processing for all
failing tests (remember to use `-mllvm` for clang/flang to forward arguments to
LLVM).
2. For most test failures, the changes are trivial and mechanical, enough that
they can be done by script; see the migration guide for a guide on how to do
this: https://llvm.org/docs/RemoveDIsDebugInfo.html#test-updates
3. If any tests fail for reasons other than FileCheck check lines that need
updating, such as assertion failures, that is most likely a real bug with this
patch and should be reported as such.

For more information, see the recent PSA:
https://discourse.llvm.org/t/psa-ir-output-changing-from-debug-intrinsics-to-debug-records/79578
2024-06-14 15:07:27 +01:00
Kareem Ergawy
7db4e6c1ec
[OpenMP][LLVM] Update alloca IP after PrivCB in OMPIRBUIlder (#93920)
Fixes a crash uncovered by
[pr77666.f90](https://github.com/llvm/llvm-test-suite/blob/main/Fortran/gfortran/regression/gomp/pr77666.f90)
in the test suite when delayed privatization is enabled by default.

In particular, whenever `PrivCB` (the callback responsible for
generating privatizaiton logic for an OMP variable) generates a
multi-block privatization region, the insertion point diverges: the BB
component of the IP can become a different BB from the parent block of
the instruction iterator component of the IP. This PR updates the IP to
make sure that the BB is the parent block of the instruction iterator.
2024-06-05 05:13:47 +02:00
Dominik Adamski
2b1948c2be [NFC][OpenMP][Clang]Update OpenMP clang tests
Replace hardcoded constants by regular expressions
2023-11-03 05:13:06 -05:00
Aaron Ballman
84a3aadf0f Diagnose use of VLAs in C++ by default
Reapplication of 7339c0f782d5c70e0928f8991b0c05338a90c84c with a fix
for a crash involving arrays without a size expression.

Clang supports VLAs in C++ as an extension, but we currently only warn
on their use when you pass -Wvla, -Wvla-extension, or -pedantic.
However, VLAs as they're expressed in C have been considered by WG21
and rejected, are easy to use accidentally to the surprise of users
(e.g., https://ddanilov.me/default-non-standard-features/), and they
have potential security implications beyond constant-size arrays
(https://wiki.sei.cmu.edu/confluence/display/c/ARR32-C.+Ensure+size+arguments+for+variable+length+arrays+are+in+a+valid+range).
C++ users should strongly consider using other functionality such as
std::vector instead.

This seems like sufficiently compelling evidence to warn users about
VLA use by default in C++ modes. This patch enables the -Wvla-extension
diagnostic group in C++ language modes by default, and adds the warning
group to -Wall in GNU++ language modes. The warning is still opt-in in
C language modes, where support for VLAs is somewhat less surprising to
users.

RFC: https://discourse.llvm.org/t/rfc-diagnosing-use-of-vlas-in-c/73109
Fixes https://github.com/llvm/llvm-project/issues/62836
Differential Revision: https://reviews.llvm.org/D156565
2023-10-20 13:10:03 -04:00
Aaron Ballman
f5043f46c0 Revert "Diagnose use of VLAs in C++ by default"
This reverts commit 7339c0f782d5c70e0928f8991b0c05338a90c84c.

Breaks bots:
https://lab.llvm.org/buildbot/#/builders/139/builds/51875
https://lab.llvm.org/buildbot/#/builders/164/builds/45262
2023-10-20 10:00:18 -04:00
Aaron Ballman
7339c0f782 Diagnose use of VLAs in C++ by default
Clang supports VLAs in C++ as an extension, but we currently only warn
on their use when you pass -Wvla, -Wvla-extension, or -pedantic.
However, VLAs as they're expressed in C have been considered by WG21
and rejected, are easy to use accidentally to the surprise of users
(e.g., https://ddanilov.me/default-non-standard-features/), and they
have potential security implications beyond constant-size arrays
(https://wiki.sei.cmu.edu/confluence/display/c/ARR32-C.+Ensure+size+arguments+for+variable+length+arrays+are+in+a+valid+range).
C++ users should strongly consider using other functionality such as
std::vector instead.

This seems like sufficiently compelling evidence to warn users about
VLA use by default in C++ modes. This patch enables the -Wvla-extension
diagnostic group in C++ language modes by default, and adds the warning
group to -Wall in GNU++ language modes. The warning is still opt-in in
C language modes, where support for VLAs is somewhat less surprising to
users.

RFC: https://discourse.llvm.org/t/rfc-diagnosing-use-of-vlas-in-c/73109
Fixes https://github.com/llvm/llvm-project/issues/62836
Differential Revision: https://reviews.llvm.org/D156565
2023-10-20 09:50:21 -04:00
Matt Arsenault
25bc999d1f Intrinsics: Add type overload to stacksave and stackstore
This allows use with non-0 address space stacks. llvm_ptr_ty should
never be used. This could use some more percolation up through mlir,
but this is enough to fix existing tests.

https://reviews.llvm.org/D156666
2023-08-09 18:33:11 -04:00
Itay Bookstein
782c59a4ee [OpenMP] Prefix outlined and reduction func names with original func's name
This patch prefixes omp outlined helpers and reduction funcs
with the original function's name.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D140722
2023-04-19 23:00:26 +03:00
Itay Bookstein
6fdd13e0ec Revert "[OpenMP] Prefix outlined and reduction func names with original func's name"
This reverts commit 029bfc311d4d7d3cd90be81bb08c046848796d02.
2023-04-19 19:08:49 +03:00
Itay Bookstein
029bfc311d [OpenMP] Prefix outlined and reduction func names with original func's name
This patch attempts to prefix omp outlined helpers and reduction funcs
with the original function's name.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D140722
2023-04-19 19:05:21 +03:00
Johannes Doerfert
afeeab1ff3 [OpenMP][NFC] Rerun the update_cc_test_checks on most OpenMP tests
The script changes over time and unrelated changes to the test check
lines should not pollute future revisions.
2023-01-09 16:40:20 -08:00
John Brawn
6b8900f7f9 [clang][CodeGen] Add default attributes to __clang_call_terminate
When generating __clang_call_terminate use SetLLVMFunctionAttributes
to set the default function attributes, like we do for all the other
functions generated by clang. This fixes a problem where target
features from the command line weren't being applied to this function.

Differential Revision: https://reviews.llvm.org/D138679
2022-11-29 13:09:52 +00:00
Nikita Popov
a290f3c8fc [OpenMP] Convert tests to opaque pointers (NFC)
Conversion performed using the script at:
https://gist.github.com/nikic/98357b71fd67756b0f064c9517b62a34

These are only tests where no manual fixup was required.
2022-10-07 14:58:27 +02:00
Dhruva Chakrabarti
839ac62c50 Revert "[OpenMP] Codegen aggregate for outlined function captures"
This reverts commit 7539e9cf811e590d9f12ae39673ca789e26386b4.
2022-09-15 03:08:46 +00:00
Giorgis Georgakoudis
7539e9cf81 [OpenMP] Codegen aggregate for outlined function captures
Parallel regions are outlined as functions with capture variables explicitly generated as distinct parameters in the function's argument list. That complicates the fork_call interface in the OpenMP runtime: (1) the fork_call is variadic since there is a variable number of arguments to forward to the outlined function, (2) wrapping/unwrapping arguments happens in the OpenMP runtime, which is sub-optimal, has been a source of ABI bugs, and has a hardcoded limit (16) in the number of arguments, (3)  forwarded arguments must cast to pointer types, which complicates debugging. This patch avoids those issues by aggregating captured arguments in a struct to pass to the fork_call.

Reviewed By: jdoerfert, jhuber6, ABataev

Differential Revision: https://reviews.llvm.org/D102107
2022-09-15 00:54:05 +00:00
Nikita Popov
532dc62b90 [OpaquePtrs][Clang] Add -no-opaque-pointers to tests (NFC)
This adds -no-opaque-pointers to clang tests whose output will
change when opaque pointers are enabled by default. This is
intended to be part of the migration approach described in
https://discourse.llvm.org/t/enabling-opaque-pointers-by-default/61322/9.

The patch has been produced by replacing %clang_cc1 with
%clang_cc1 -no-opaque-pointers for tests that fail with opaque
pointers enabled. Worth noting that this doesn't cover all tests,
there's a remaining ~40 tests not using %clang_cc1 that will need
a followup change.

Differential Revision: https://reviews.llvm.org/D123115
2022-04-07 12:09:47 +02:00
Giorgis Georgakoudis
7cb4c26173 [OMPIRBuilder] Generate aggregate argument for parallel region outlined functions
Summary:
This patch modifies code generation in OpenMPIRBuilder to pass arguments
to the parallel region outlined function in an aggregate (struct),
besides the global_tid and bound_tid arguments. It depends on the
updated CodeExtractor (see D96854) for support. It mirrors functionality
of Clang codegen (see D102107).

Differential Revision: https://reviews.llvm.org/D110114
2022-01-25 20:53:45 -05:00
hyeongyu kim
1b1c8d83d3 [Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default
Turning on `enable_noundef_analysis` flag allows better codegen by removing freeze instructions.
I modified clang by renaming `enable_noundef_analysis` flag to `disable-noundef-analysis` and turning it off by default.

Test updates are made as a separate patch: D108453

Reviewed By: eugenis

Differential Revision: https://reviews.llvm.org/D105169
2022-01-16 18:54:17 +09:00
hyeongyu kim
fd9b099906 Revert "[Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default"
This reverts commit aacfbb953eb705af2ecfeb95a6262818fa85dd92.

Revert "Fix lit test failures in CodeGenCoroutines"

This reverts commit 63fff0f5bffe20fa2c84a45a41161afa0043cb34.
2021-11-09 02:15:55 +09:00
hyeongyukim
aacfbb953e [Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default
Turning on `enable_noundef_analysis` flag allows better codegen by removing freeze instructions.
I modified clang by renaming `enable_noundef_analysis` flag to `disable-noundef-analysis` and turning it off by default.

Test updates are made as a separate patch: D108453

Reviewed By: eugenis

Differential Revision: https://reviews.llvm.org/D105169

[Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default (2)

This patch updates test files after D105169.
Autogenerated test codes are changed by `utils/update_cc_test_checks.py,` and non-autogenerated test codes are changed as follows:

(1) I wrote a python script that (partially) updates the tests using regex: {F18594904} The script is not perfect, but I believe it gives hints about which patterns are updated to have `noundef` attached.

(2) The remaining tests are updated manually.

Reviewed By: eugenis

Differential Revision: https://reviews.llvm.org/D108453

Resolve lit failures in clang after 8ca4b3e's land

Fix lit test failures in clang-ppc* and clang-x64-windows-msvc

Fix missing failures in clang-ppc64be* and retry fixing clang-x64-windows-msvc

Fix internal_clone(aarch64) inline assembly
2021-11-06 19:19:22 +09:00
Juneyoung Lee
89ad2822af Revert "[Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default"
This reverts commit 7584ef766a7219b6ee5a400637206d26e0fa98ac.
2021-11-06 15:39:19 +09:00
Juneyoung Lee
7584ef766a [Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default
Turning on `enable_noundef_analysis` flag allows better codegen by removing freeze instructions.
I modified clang by renaming `enable_noundef_analysis` flag to `disable-noundef-analysis` and turning it off by default.

Test updates are made as a separate patch: D108453

Reviewed By: eugenis

Differential Revision: https://reviews.llvm.org/D105169
2021-11-06 15:36:42 +09:00
Juneyoung Lee
f193bcc701 Revert D105169 due to the two-stage failure in ASAN
This reverts the following commits:
37ca7a795b277c20c02a218bf44052278c03344b
9aa6c72b92b6c89cc6d23b693257df9af7de2d15
705387c5074bcca36d626882462ebbc2bcc3bed4
8ca4b3ef19fe82d7ad6a6e1515317dcc01b41515
80dba72a669b5416e97a42fd2c2a7bc5a6d3f44a
2021-10-18 23:52:46 +09:00
Juneyoung Lee
8ca4b3ef19 [Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default (2)
This patch updates test files after D105169.
Autogenerated test codes are changed by `utils/update_cc_test_checks.py,` and non-autogenerated test codes are changed as follows:

(1) I wrote a python script that (partially) updates the tests using regex: {F18594904} The script is not perfect, but I believe it gives hints about which patterns are updated to have `noundef` attached.

(2) The remaining tests are updated manually.

Reviewed By: eugenis

Differential Revision: https://reviews.llvm.org/D108453
2021-10-16 12:01:41 +09:00
Giorgis Georgakoudis
ac90dfc43a Revert "[OpenMP] Codegen aggregate for outlined function captures"
This reverts commit 1d66649adf28d48ae1731516d87fb899426e3349.

Revert to fix AMG GPU issue.
2021-09-21 13:20:39 -07:00
Giorgis Georgakoudis
1d66649adf [OpenMP] Codegen aggregate for outlined function captures
Parallel regions are outlined as functions with capture variables explicitly generated as distinct parameters in the function's argument list. That complicates the fork_call interface in the OpenMP runtime: (1) the fork_call is variadic since there is a variable number of arguments to forward to the outlined function, (2) wrapping/unwrapping arguments happens in the OpenMP runtime, which is sub-optimal, has been a source of ABI bugs, and has a hardcoded limit (16) in the number of arguments, (3)  forwarded arguments must cast to pointer types, which complicates debugging. This patch avoids those issues by aggregating captured arguments in a struct to pass to the fork_call.

Reviewed By: jdoerfert, jhuber6

Differential Revision: https://reviews.llvm.org/D102107
2021-09-21 10:50:04 -07:00
Vyacheslav Zakharin
2e192ab1f4 [CodeExtractor] Preserve topological order for the return blocks.
Differential Revision: https://reviews.llvm.org/D108673
2021-08-25 08:09:01 -07:00
Giorgis Georgakoudis
fb0cf01795 Revert "[OpenMP] Codegen aggregate for outlined function captures"
This reverts commit e9c7291cb25f071f1a1dfa4049ed9f5a8a217b3e.

Fix failing tests
2021-07-19 07:54:26 -07:00
Giorgis Georgakoudis
e9c7291cb2 [OpenMP] Codegen aggregate for outlined function captures
Parallel regions are outlined as functions with capture variables explicitly generated as distinct parameters in the function's argument list. That complicates the fork_call interface in the OpenMP runtime: (1) the fork_call is variadic since there is a variable number of arguments to forward to the outlined function, (2) wrapping/unwrapping arguments happens in the OpenMP runtime, which is sub-optimal, has been a source of ABI bugs, and has a hardcoded limit (16) in the number of arguments, (3)  forwarded arguments must cast to pointer types, which complicates debugging. This patch avoids those issues by aggregating captured arguments in a struct to pass to the fork_call.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D102107
2021-07-16 23:27:44 -07:00
Johannes Doerfert
6ff380f439 [OpenMP][NFC] Remove SIMD check lines for non-simd tests
If a test does not contain an " simd" but -fopenmp-simd RUN lines we can
just check that we do not create __kmpc|__tgt calls.

Reviewed By: ABataev

Differential Revision: https://reviews.llvm.org/D101973
2021-05-19 21:35:33 -05:00
Giorgis Georgakoudis
207b08a913 [OpenMP][NFC] Refactor Clang OpenMP tests using update_cc_test_checks
This patch refactors a subset of Clang OpenMP tests, generating checklines using the update_cc_test_checks script. This refactoring facilitates updating the Clang OpenMP code generation codebase by automating test generation.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D101849
2021-05-05 20:08:38 -07:00
Giorgis Georgakoudis
f016c06abb Revert "[OpenMP][NFC] Refactor Clang OpenMP tests using update_cc_test_checks"
This reverts commit 956cae2f09b21429dbcb02066c99e35a239aa4bf.
2021-05-04 17:12:32 -07:00
Giorgis Georgakoudis
956cae2f09 [OpenMP][NFC] Refactor Clang OpenMP tests using update_cc_test_checks
This patch refactors a subset of Clang OpenMP tests, generating checklines using the update_cc_test_checks script. This refactoring facilitates updating the Clang OpenMP code generation codebase by automating test generation.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D101849
2021-05-04 16:58:45 -07:00
Fangrui Song
ec9f2c3be0 test/OpenMP/parallel_codegen.cpp: Allow multiple result attributes
On many targets the matched line is `define dso_local i32 @main` while
on ppc64 it is `define dso_local signext i32 @main`.
2021-01-01 10:46:34 -08:00
Fangrui Song
fd739804e0 [test] Add {{.*}} to make ELF tests immune to dso_local/dso_preemptable/(none) differences
For a default visibility external linkage definition, dso_local is set for ELF
-fno-pic/-fpie and COFF and Mach-O. Since default clang -cc1 for ELF is similar
to -fpic ("PIC Level" is not set), this nuance causes unneeded binary format differences.

To make emitted IR similar, ELF -cc1 -fpic will default to -fno-semantic-interposition,
which sets dso_local for default visibility external linkage definitions.

To make this flip smooth and enable future (dso_local as definition default),
this patch replaces (function) `define ` with `define{{.*}} `,
(variable/constant/alias) `= ` with `={{.*}} `, or inserts appropriate `{{.*}} `.
2020-12-31 00:27:11 -08:00
Alex Zinenko
240dd92432 [OpenMPIRBuilder] forward arguments as pointers to outlined function
OpenMPIRBuilder::createParallel outlines the body region of the parallel
construct into a new function that accepts any value previously defined outside
the region as a function argument. This function is called back by OpenMP
runtime function __kmpc_fork_call, which expects trailing arguments to be
pointers. If the region uses a value that is not of a pointer type, e.g. a
struct, the produced code would be invalid. In such cases, make createParallel
emit IR that stores the value on stack and pass the pointer to the outlined
function instead. The outlined function then loads the value back and uses as
normal.

Reviewed By: jdoerfert, llitchev

Differential Revision: https://reviews.llvm.org/D92189
2020-12-02 14:59:41 +01:00
Johannes Doerfert
fa5d22a045 [OpenMP][NFC] Reuse OMPIRBuilder struct ident_t handling in Clang
Replace the `ident_t` handling in Clang with the methods offered by the
OMPIRBuilder. This cuts down on the clang code as well as the
differences between the two, making further transitions easier. Tests
have changed but there should not be a real functional change. The most
interesting difference is probably that we stop generating local ident_t
allocations for now and just use globals. Given that this happens only
with debug info, the location part of the `ident_t` is probably bigger
than the test anyway. As the location part is already a global, we can
avoid the allocation, memcpy, and store in favor of a constant global
that is slightly bigger. This can be revisited if there are
complications.

Reviewed By: ABataev

Differential Revision: https://reviews.llvm.org/D80735
2020-08-10 17:13:26 -05:00
Fangrui Song
b0b5162fc2 [Driver] Pass -gno-column-info instead of -dwarf-column-info
Making -g[no-]column-info opt out reduces the length of a typical CC1 command line.
Additionally, in a non-debug compile, we won't see -dwarf-column-info.
2020-07-05 11:50:38 -07:00
Eli Friedman
62f3ef2b53 [CGCall] Annotate references with "align" attribute.
If we're going to assume references are dereferenceable, we should also
assume they're aligned: otherwise, we can't actually dereference them.

See also D80072.

Differential Revision: https://reviews.llvm.org/D80166
2020-05-19 20:21:30 -07:00
Alexey Bataev
2b8c1ac9ca [OPENMP]Fix the test to pacify buildbots, NFC. 2020-04-09 11:28:50 -04:00
Alexey Bataev
56c3b2b091 [OPENMP]Fix capturing of global variables in OpenMP regions.
Summary:
The global variable should be captured in the region only if it was
privitized in the region or in any of the outer regions. Otherwise, it
should not be captured.

Reviewers: jdoerfert

Subscribers: yaxunl, guansong, cfe-commits, caomhin

Tags: #clang

Differential Revision: https://reviews.llvm.org/D77731
2020-04-09 10:36:09 -04:00
Alexey Bataev
dbe86786f7 [OPENMP]Do not capture global marked as shared in OpenMP region.
No need to capture the global variable marked as shared in the OpenMP
region, the original variable can be used.
2020-04-07 17:33:17 -04:00
Nikita Popov
f6875c434e Reapply [IRBuilder] Always respect inserter/folder
Some IRBuilder methods that were originally defined on
IRBuilderBase do not respect custom IRBuilder inserters/folders,
because those were not accessible prior to D73835. Fix this by
making use of existing (and now accessible) IRBuilder methods,
which will handle inserters/folders correctly.

There are some changes in OpenMP and Instrumentation tests, where
bitcasts now get constant folded. I've also highlighted one
InstCombine test which now finishes in two rather than three
iterations, thanks to new instructions being inserted into the
worklist.

Differential Revision: https://reviews.llvm.org/D74787
2020-02-19 20:51:38 +01:00
Nikita Popov
b92b1701cd Revert "[IRBuilder] Always respect inserter/folder"
This reverts commit f12fb2d99b8dd0dbef1c79f1d401200150f2d0bd.

I missed some changes in instrumentation test cases.
2020-02-19 17:51:55 +01:00
Nikita Popov
f12fb2d99b [IRBuilder] Always respect inserter/folder
Some IRBuilder methods that were originally defined on
IRBuilderBase do not respect custom IRBuilder inserters/folders,
because those were not accessible prior to D73835. Fix this by
making use of existing (and now accessible) IRBuilder methods,
which will handle inserters/folders correctly.

There are some changes in OpenMP tests, where bitcasts now get
constant folded. I've also highlighted one InstCombine test which
now finishes in two rather than three iterations, thanks to new
instructions being inserted into the worklist.

Differential Revision: https://reviews.llvm.org/D74787
2020-02-19 17:44:43 +01:00
Fangrui Song
dbc96b518b Revert "[CodeGenModule] Assume dso_local for -fpic -fno-semantic-interposition"
This reverts commit 789a46f2d742e11edaade28cb59a0f4d2a1d770e.

Accidentally committed.
2020-02-03 10:09:39 -08:00
Fangrui Song
789a46f2d7 [CodeGenModule] Assume dso_local for -fpic -fno-semantic-interposition
Summary:
Clang -fpic defaults to -fno-semantic-interposition (GCC -fpic defaults
to -fsemantic-interposition).
Users need to specify -fsemantic-interposition to get semantic
interposition behavior.

Semantic interposition is currently a best-effort feature. There may
still be some cases where it is not handled well.

Reviewers: peter.smith, rnk, serge-sans-paille, sfertile, jfb, jdoerfert

Subscribers: dschuff, jyknight, dylanmckay, nemanjai, jvesely, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, sabuasal, niosHD, jrtc27, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, arphaman, PkmX, jocewei, jsji, Jim, lenary, s.egerton, pzheng, sameer.abuasal, apazos, luismarques, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D73865
2020-02-03 09:52:48 -08:00