commit | f02c5f3478318075d1a469203900e452ba651421 | [log] [tgz] |
---|---|---|
author | Gabor Marton <gabor.marton@ericsson.com> | Fri Nov 26 10:59:09 2021 +0100 |
committer | Gabor Marton <gabor.marton@ericsson.com> | Tue Nov 30 11:13:13 2021 +0100 |
tree | 0f9102e4bfe6eb4764fcfc72bf46d21e66d1f9fa | |
parent | 9a14adeae00015798843ff5cad987e5fdbdddb34 [diff] |
[Analyzer][solver] Do not remove the simplified symbol from the eq class Currently, during symbol simplification we remove the original member symbol from the equivalence class (`ClassMembers` trait). However, we keep the reverse link (`ClassMap` trait), in order to be able the query the related constraints even for the old member. This asymmetry can lead to a problem when we merge equivalence classes: ``` ClassA: [a, b] // ClassMembers trait, a->a, b->a // ClassMap trait, a is the representative symbol ``` Now lets delete `a`: ``` ClassA: [b] a->a, b->a ``` Let's merge the trivial class `c` into ClassA: ``` ClassA: [c, b] c->c, b->c, a->a ``` Now after the merge operation, `c` and `a` are actually in different equivalence classes, which is inconsistent. One solution to this problem is to simply avoid removing the original member and this is what this patch does. Other options I have considered: 1) Always merge the trivial class into the non-trivial class. This might work most of the time, however, will fail if we have to merge two non-trivial classes (in that case we no longer can track equivalences precisely). 2) In `removeMember`, update the reverse link as well. This would cease the inconsistency, but we'd loose precision since we could not query the constraints for the removed member. Differential Revision: https://reviews.llvm.org/D114619
This directory and its sub-directories contain source code for LLVM, a toolkit for the construction of highly optimized compilers, optimizers, and run-time environments.
The README briefly describes how to get started with building LLVM. For more information on how to contribute to the LLVM project, please take a look at the Contributing to LLVM guide.
Taken from https://llvm.org/docs/GettingStarted.html.
Welcome to the LLVM project!
The LLVM project has multiple components. The core of the project is itself called “LLVM”. This contains all of the tools, libraries, and header files needed to process intermediate representations and convert them into object files. Tools include an assembler, disassembler, bitcode analyzer, and bitcode optimizer. It also contains basic regression tests.
C-like languages use the Clang front end. This component compiles C, C++, Objective-C, and Objective-C++ code into LLVM bitcode -- and from there into object files, using LLVM.
Other components include: the libc++ C++ standard library, the LLD linker, and more.
The LLVM Getting Started documentation may be out of date. The Clang Getting Started page might have more accurate information.
This is an example work-flow and configuration to get and build the LLVM source:
Checkout LLVM (including related sub-projects like Clang):
git clone https://github.com/llvm/llvm-project.git
Or, on windows, git clone --config core.autocrlf=false https://github.com/llvm/llvm-project.git
Configure and build LLVM and Clang:
cd llvm-project
cmake -S llvm -B build -G <generator> [options]
Some common build system generators are:
Ninja
--- for generating Ninja build files. Most llvm developers use Ninja.Unix Makefiles
--- for generating make-compatible parallel makefiles.Visual Studio
--- for generating Visual Studio projects and solutions.Xcode
--- for generating Xcode projects.Some common options:
-DLLVM_ENABLE_PROJECTS='...'
--- semicolon-separated list of the LLVM sub-projects you'd like to additionally build. Can include any of: clang, clang-tools-extra, compiler-rt,cross-project-tests, flang, libc, libclc, libcxx, libcxxabi, libunwind, lld, lldb, mlir, openmp, polly, or pstl.
For example, to build LLVM, Clang, libcxx, and libcxxabi, use -DLLVM_ENABLE_PROJECTS="clang;libcxx;libcxxabi"
.
-DCMAKE_INSTALL_PREFIX=directory
--- Specify for directory the full path name of where you want the LLVM tools and libraries to be installed (default /usr/local
).
-DCMAKE_BUILD_TYPE=type
--- Valid options for type are Debug, Release, RelWithDebInfo, and MinSizeRel. Default is Debug.
-DLLVM_ENABLE_ASSERTIONS=On
--- Compile with assertion checks enabled (default is Yes for Debug builds, No for all other build types).
cmake --build build [-- [options] <target>]
or your build system specified above directly.
The default target (i.e. ninja
or make
) will build all of LLVM.
The check-all
target (i.e. ninja check-all
) will run the regression tests to ensure everything is in working order.
CMake will generate targets for each tool and library, and most LLVM sub-projects generate their own check-<project>
target.
Running a serial build will be slow. To improve speed, try running a parallel build. That's done by default in Ninja; for make
, use the option -j NNN
, where NNN
is the number of parallel jobs, e.g. the number of CPUs you have.
For more information see CMake
Consult the Getting Started with LLVM page for detailed information on configuring and compiling LLVM. You can visit Directory Layout to learn about the layout of the source code tree.