LLVM 10.0.0 to be Released

New version of the popular development toolkit brings, among other things, support for the C++ Concepts
26 March 2020   948

After six months of development, the release of the LLVM 10.0 project, a GCC-compatible toolkit (compilers, optimizers, and code generators), compiling programs into an intermediate bitcode of RISC-like virtual instructions (a low-level virtual machine with a multi-level optimization system), is presented. The generated pseudo-code can be converted using the JIT compiler into machine instructions directly at the time of program execution.

Among the new features of LLVM 10.0, there are support for C ++ Concepts (C ++ Concepts), termination of the launch of Clang in the form of a separate process, support for CFG checks (control flow guard) for Windows, and support for new CPU features.

The main innovations of LLVM 10.0:

  • New interprocedural optimizations and analyzers have been added to the Attributor framework. The prediction of the state of 19 different attributes, including 12 attributes of 12 LLVM IR and 7 abstract attributes such as liveness, is provided.
  • New built-in compiler matrix mathematical functions (Intrinsics) have been added, which, when compiled, are replaced by effective vector instructions.
  • Numerous improvements to the backends for the X86, AArch64, ARM, SystemZ, MIPS, AMDGPU, and PowerPC architectures. Added support for Cortex-A65, Cortex-A65AE, Neoverse E1 and Neoverse N1 CPUs. For ARMv8.1-M, ​​the code generation process has been optimized (for example, support for loops with minimal overhead has appeared) and support for auto-vectorization using the MVE extension has been added. Improved support for CPU MIPS Octeon. PowerPC includes vectorization of mathematical routines using the MASSV (Mathematical Acceleration SubSystem) library, improved code generation, and optimized memory access from loops. For x86, the processing of vector types v2i32, v4i16, v2i16, v8i8, v4i8 and v2i8 has been changed.
  • Improved code generator for WebAssembly. Added support for TLS (Thread-Local Storage) and atomic.fence instructions. Significantly expanded support for SIMD. WebAssembly object files added the ability to use function signatures with multiple values.
  • When processing cycles, the MemorySSA analyzer is used to determine the dependencies between different memory operations. MemorySSA can reduce compilation and execution time, or can be used instead of AliasSetTracker without sacrificing performance.
  • The LLDB debugger has significantly improved support for the DWARF v5 format. Improved build support with MinGW and added the initial ability to debug Windows executable files for ARM and ARM64 architectures. Added descriptions of options offered when autocompleting input by pressing tabs.
  • Enhanced LLD Linker Features. Improved support for the ELF format, including full compatibility of glob templates with the GNU linker, added support for the compressed debug sections ".zdebug", added the PT_GNU_PROPERTY property to determine the .note.gnu.property section (can be used in future Linux kernels), implemented modes "-z noseparate-code", "-z separate-code" and "-z separate-loadable-segments". Improved support for MinGW and WebAssembly.

Get more at the release notes.

Mozilla to Test Firefox Better Web Service

The main idea of ​​the project is a paid subscription to finance the creation of content, which allows website owners stop showing ads
25 March 2020   349

As part of the Test Pilot program, Mozilla invited Firefox users to test the new Firefox Better Web with Scroll service, which is experimenting with alternative types of site financing. Testing is available only to users of desktop versions of Firefox from the United States. A single Firefox account, also used for synchronization, is used to connect. To participate, you must install a special add-on in Firefox.

The main idea of ​​the project is to use a paid subscription to the service to finance the creation of content, which allows website owners to do without showing ads. The service is organized in conjunction with the Scroll project, developing a model similar to that implemented in the Brave browser - the user pays for a subscription to the service ($ 2.49 per month) and has the ability to view sites that have joined the Scroll initiative without advertising inserts. At least 40% of the funds received from users is distributed between the owners of partner sites, in a proportion corresponding to the time spent by users subscribed to the service on each site (data on how much time is spent on sites Scroll service collects using JavaScript code placed on partner sites).

Get more info at the official blog.