Add `dead_on_return` attribute, which is meant to be taken advantage by the frontend, and states that the memory pointed to by the argument is dead upon function return. As with `byval`, it is supposed to be used for passing aggregates by value. The difference lies in the ABI: `byval` implies that the pointer is explicitly passed as argument to the callee (during codegen the copy is emitted as per byval contract), whereas a `dead_on_return`-marked argument implies that the copy already exists in the IR, is located at a specific stack offset within the caller, and this memory will not be read further by the caller upon callee return – or otherwise poison, if read before being written. RFC: https://discourse.llvm.org/t/rfc-add-dead-on-return-attribute/86871.
This flag was used to let us incrementally introduce debug records into LLVM, however everything is now using records. It serves no purpose now, so delete it.
Start removing debug intrinsics support -- starting with the flag that controls production of their replacement, debug records. This patch removes the command-line-flag and with it the ability to switch back to intrinsics. The module / function / block level "IsNewDbgInfoFormat" flags get hardcoded to true, I'll to incrementally remove things that depend on those flags.
Reapply PR142507 with fix for test: add in the same x86_64-linux requirement as other tests as the stack ids are currently computed differently on big endian systems. This will be investigated separately. In order to allow selective reporting of context hinting during the LTO link, and in the future to allow selective more aggressive cloning, add an option to specify a minimum percent of the max cold size in the profile summary. Contexts that meet that threshold will get context size info metadata (and ThinLTO summary information) on the associated allocations. Specifying -memprof-report-hinted-sizes during the pre-LTO compile step will continue to cause all contexts to receive this metadata. But specifying -memprof-report-hinted-sizes only during the LTO link will cause only those that meet the new threshold and have the metadata to get reported. To support this, because the alloc info summary and associated bitcode requires the context size information to be in the same order as the other context information, 0s are inserted for contexts without this metadata. The bitcode writer uses a more compact format for the context ids to allow better compression of the 0s. As part of this change several helper methods are added to query whether metadata contains context size info on any or all contexts.
Reverts llvm/llvm-project#142507 due to buildbot failures that I will look into tomorrow.
In order to allow selective reporting of context hinting during the LTO link, and in the future to allow selective more aggressive cloning, add an option to specify a minimum percent of the max cold size in the profile summary. Contexts that meet that threshold will get context size info metadata (and ThinLTO summary information) on the associated allocations. Specifying -memprof-report-hinted-sizes during the pre-LTO compile step will continue to cause all contexts to receive this metadata. But specifying -memprof-report-hinted-sizes only during the LTO link will cause only those that meet the new threshold and have the metadata to get reported. To support this, because the alloc info summary and associated bitcode requires the context size information to be in the same order as the other context information, 0s are inserted for contexts without this metadata. The bitcode writer uses a more compact format for the context ids to allow better compression of the 0s. As part of this change several helper methods are added to query whether metadata contains context size info on any or all contexts.
## Purpose This patch is one in a series of code-mods that annotate LLVM’s public interface for export. This patch annotates the `llvm/AsmParser`, `llvm/BinaryFormat`, `llvm/Bitcode` and `llvm/Bitstream libraries. These annotations currently have no meaningful impact on the LLVM build; however, they are a prerequisite to support an LLVM Windows DLL (shared library) build. ## Background This effort is tracked in #109483. Additional context is provided in [this discourse](https://discourse.llvm.org/t/psa-annotating-llvm-public-interface/85307), and documentation for `LLVM_ABI` and related annotations is found in the LLVM repo [here](https://github.com/llvm/llvm-project/blob/main/llvm/docs/InterfaceExportAnnotations.rst). The bulk of these changes were generated automatically using the [Interface Definition Scanner (IDS)](https://github.com/compnerd/ids) tool, followed formatting with `git clang-format`. The following manual adjustments were also applied after running IDS on Linux: - Add `LLVM_ABI_FRIEND` to friend member functions declared with `LLVM_ABI` - Add `LLVM_ABI` symbols that require export but are not declared in headers ## Validation Local builds and tests to validate cross-platform compatibility. This included llvm, clang, and lldb on the following configurations: - Windows with MSVC - Windows with Clang - Linux with GCC - Linux with Clang - Darwin with Clang
Fixes errors about duplicate PHI edges when the input had duplicates with constexprs in them. The constexpr translation makes new basic blocks, causing the verifier to complain about duplicate entries in PHI nodes.