New Loop Vectorizer
I would like to give a brief update regarding the development of the Loop Vectorizer. LLVM now has two vectorizers: The Loop Vectorizer, which operates on Loops, and the Basic Block Vectorizer, which optimizes straight-line code.
Read more…LLVM Developer Meeting 2012
The 2012 LLVM Developer Meeting is now complete and was a great success. If you are interested in the talks, a complete set of slides, videos, and posters are now available.
Read more…Life of an instruction in LLVM
LLVM is a complex piece of software. There are several paths one may take on the quest of understanding how it works, none of which is simple. I recently had to dig in some areas of LLVM I was not previously familiar with, and this article is one of the outcomes of this quest.
Read more…LLVM Developer Meeting 2011
The 2011 LLVM Devloper Meeting has come and gone, and it was a great event. It featured 17 great talks, several BOF sessions, a poster session, and lots of informal discussions between all sorts of people interested in LLVM and its subprojects.
Read more…NVIDIA CUDA 4.1 Compiler Now Built on LLVM
From the NVIDIA CUDA compiler team: CUDA is a parallel programming model and platform created by NVIDIA for harnessing the power of hundreds of cores in modern graphics processing units (GPUs).
Read more…LLVM 3.1 vector changes
Intel uses the Low-Level Virtual Machine (LLVM) in a number of products, including the Intel® OpenCL SDK. The SDK's implicit vectorization module generates LLVM-IR (intermediate representation) which uses vector types.
Read more…LLVM 3.0 Exception Handling Redesign
One of the biggest IR changes in the LLVM 3.0 release is a redesign and reimplementation of the LLVM IR exception handling model. The old model, while it worked for most cases, fell over in some key situations, leading to obscure miscompilations, missed optimizations, and poor compile time.
Read more…LLVM 3.0 Type System Rewrite
One of the most pervasive IR (and thus compiler API) changes in LLVM 3.0 was a complete reimplementation of the LLVM IR type system. This change was long overdue (the original type system lasted from LLVM 1.
Read more…Greedy Register Allocation in LLVM 3.0
LLVM has two new register allocators: Basic and Greedy. When LLVM 3.0 is released, the default optimizing register allocator will no longer be linear scan, but the new greedy register allocator.
Read more…LLVM @ "The Architecture of Open Source Applications"
LLVM is featured in a chapter of the new book The Architecture of Open Source Applications. This chapter talks about the high-level design of LLVM, and how it differs from other contemporary compilers and JITs out there, why you might want to use it (if you're looking for compiler libraries), a simple example of writing an optimization, how the code is structured, a 10,000 foot view of how the code generator works, and some of the interesting capabilities LLVM has due to its design.
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