Add nuw attribute to inbounds GEPs where the expression used to form the GEP is an addition of unsigned indices. Relands #105496, which was reverted because it exposed a miscompilation arising from #98608. This is now fixed by #106512.
Reverts llvm/llvm-project#105496 This patch breaks: https://lab.llvm.org/buildbot/#/builders/25/builds/1952 https://lab.llvm.org/buildbot/#/builders/52/builds/1775 Somehow output is different with sanitizers. Maybe non-determinism in the code?
Add nuw attribute to inbounds GEPs where the expression used to form the GEP is an addition of unsigned indices.
Generate nuw GEPs for struct member accesses, as inbounds + non-negative implies nuw. Regression tests are updated using update scripts where possible, and by find + replace where not.
While lowering (#pragma omp target update from), clang's generated .omp_task_entry. is setting up 9 arguments while calling __tgt_target_data_update_nowait_mapper. At the same time, in __tgt_target_data_update_nowait_mapper, call to targetData<TaskAsyncInfoWrapperTy>() is converted to a sibcall assuming it has the argument count listed in the signature. AARCH64 asm sequence for this is as follows (removed unrelated insns): ` .omp_task_entry..108: sub sp, sp, #32 stp x29, x30, sp, #16 // 16-byte Folded Spill add x29, sp, #16 str x8, sp, #8. // stack canary str xzr, [sp] bl __tgt_target_data_update_nowait_mapper __tgt_target_data_update_nowait_mapper: sub sp, sp, #32 stp x29, x30, sp, #16 // 16-byte Folded Spill add x29, sp, #16 str x8, sp, #8 // stack canary // Sibcall argument setup adrp x8, :got:_Z16targetDataUpdateP7ident_tR8DeviceTyiPPvS4_PlS5_S4_S4_R11AsyncInfoTyb ldr x8, [x8, :got_lo12:_Z16targetDataUpdateP7ident_tR8DeviceTyiPPvS4_PlS5_S4_S4_R11AsyncInfoTyb] stp x9, x8, x29, #16 adrp x8, .L.str.8 add x8, x8, :lo12:.L.str.8 str x8, x29, #32. <==. This is the insn that erases $fp ldp x29, x30, sp, #16 // 16-byte Folded Reload add sp, sp, #32 // Sibcall b ZL10targetDataI22TaskAsyncInfoWrapperTyEvP7ident_tliPPvS4_PlS5_S4_S4_PFiS2_R8DeviceTyiS4_S4_S5_S5_S4_S4_R11AsyncInfoTybEPKcSD ` On AArch64, call to __tgt_target_data_update_nowait_mapper in .omp_task_entry. sets up only single space on stack and this results in ovewriting $fp and subsequent stack corruption. This issue can be credited to discrepancy of __tgt_target_data_update_nowait_mapper signature in openmp/libomptarget/include/omptarget.h taking 13 arguments while clang/lib/CodeGen/CGOpenMPRuntime.cpp and llvm/include/llvm/Frontend/OpenMP/OMPKinds.def taking only 9 arguments. This patch modifies __tgt_target_data_update_nowait_mapper signature to match .omp_task_entry usage(and other 2 files mentioned above). Co-authored-by: Kugan Vivekanandarajah <kvivekananda@nvidia.com>
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
This reverts commit 7339c0f782d5c70e0928f8991b0c05338a90c84c. Breaks bots: https://lab.llvm.org/buildbot/#/builders/139/builds/51875 https://lab.llvm.org/buildbot/#/builders/164/builds/45262
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
This patch renames the `OpenMPIRBuilderConfig` flags to reduce confusion over their meaning. `IsTargetCodegen` becomes `IsGPU`, whereas `IsEmbedded` becomes `IsTargetDevice`. The `-fopenmp-is-device` compiler option is also renamed to `-fopenmp-is-target-device` and the `omp.is_device` MLIR attribute is renamed to `omp.is_target_device`. Getters and setters of all these renamed properties are also updated accordingly. Many unit tests have been updated to use the new names, but an alias for the `-fopenmp-is-device` option is created so that external programs do not stop working after the name change. `IsGPU` is set when the target triple is AMDGCN or NVIDIA PTX, and it is only valid if `IsTargetDevice` is specified as well. `IsTargetDevice` is set by the `-fopenmp-is-target-device` compiler frontend option, which is only added to the OpenMP device invocation for offloading-enabled programs. Differential Revision: https://reviews.llvm.org/D154591
The default version of OpenMP is updated from 5.0 to 5.1 which means if -fopenmp is specified but -fopenmp-version is not specified with clang, the default version of OpenMP is taken to be 5.1. After modifying the Frontend for that, various LIT tests were updated. This patch contains all such changes. At a high level, these are the patterns of changes observed in LIT tests - # RUN lines which mentioned `-fopenmp-version=50` need to kept only if the IR for version 5.0 and 5.1 are different. Otherwise only one RUN line with no version info(i.e. default version) needs to be there. # Test cases of this sort already had the RUN lines with respect to the older default version 5.0 and the version 5.1. Only swapping the version specification flag `-fopenmp-version` from newer version RUN line to older version RUN line is required. # Diagnostics: Remove the 5.0 version specific RUN lines if there was no difference in the Diagnostics messages with respect to the default 5.1. # Diagnostics: In case there was any difference in diagnostics messages between 5.0 and 5.1, mention version specific messages in tests. # If the test contained version specific ifdef's e.g. "#ifdef OMP5" but there were no RUN lines for any other version than 5.X, then bring the code guarded by ifdef's outside and remove the ifdef's. # Some tests had RUN lines for both 5.0 and 5.1 versions, but it is found that the IR for 5.0 is not different from the 5.1, therefore such RUN lines are redundant. So, such duplicated lines are removed. # To generate CHECK lines automatically, use the script llvm/utils/update_cc_test_checks.py Reviewed By: saiislam, ABataev Differential Revision: https://reviews.llvm.org/D129635 (cherry picked from commit 9dd2999907dc791136a75238a6000f69bf67cf4e)