Open64 is a free,

open-source Open source is source code that is made freely available for possible modification and redistribution. Products include permission to use the source code, design documents, or content of the product. The open-source model is a decentralized sof ...

, optimizing

compiler In computing, a compiler is a computer program that translates computer code written in one programming language (the ''source'' language) into another language (the ''target'' language). The name "compiler" is primarily used for programs that ...

for the

Itanium Itanium ( ) is a discontinued family of 64-bit Intel microprocessors that implement the Intel Itanium architecture (formerly called IA-64). Launched in June 2001, Intel marketed the processors for enterprise servers and high-performance computin ...

and

x86-64 x86-64 (also known as x64, x86_64, AMD64, and Intel 64) is a 64-bit version of the x86 instruction set, first released in 1999. It introduced two new modes of operation, 64-bit mode and compatibility mode, along with a new 4-level paging mod ...

microprocessor A microprocessor is a computer processor where the data processing logic and control is included on a single integrated circuit, or a small number of integrated circuits. The microprocessor contains the arithmetic, logic, and control circu ...

architectures. It derives from the

SGI SGI may refer to: Companies *Saskatchewan Government Insurance *Scientific Games International, a gambling company *Silicon Graphics, Inc., a former manufacturer of high-performance computing products *Silicon Graphics International, formerly Rac ...

compilers for the MIPS

R10000 The R10000, code-named "T5", is a RISC microprocessor implementation of the MIPS IV instruction set architecture (ISA) developed by MIPS Technologies, Inc. (MTI), then a division of Silicon Graphics, Inc. (SGI). The chief designers are Chris Rowe ...

processor, called ''MIPSPro''. It was initially released in 2000 as

GNU GPL The GNU General Public License (GNU GPL or simply GPL) is a series of widely used free software licenses that guarantee end users the four freedoms to run, study, share, and modify the software. The license was the first copyleft for general us ...

software under the name Pro64. The following year, University of Delaware adopted the project and renamed the compiler to Open64. It now mostly serves as a research platform for compiler and

computer architecture In computer engineering, computer architecture is a description of the structure of a computer system made from component parts. It can sometimes be a high-level description that ignores details of the implementation. At a more detailed level, t ...

research groups. Open64 supports Fortran 77/95 and C/C++, as well as the

shared memory In computer science, shared memory is memory that may be simultaneously accessed by multiple programs with an intent to provide communication among them or avoid redundant copies. Shared memory is an efficient means of passing data between progr ...

programming model

OpenMP OpenMP (Open Multi-Processing) is an application programming interface (API) that supports multi-platform shared-memory multiprocessing programming in C, C++, and Fortran, on many platforms, instruction-set architectures and operating syste ...

. It can conduct high-quality

interprocedural analysis Interprocedural optimization (IPO) is a collection of compiler techniques used in computer programming to improve performance in programs containing many frequently used functions of small or medium length. IPO differs from other compiler optimiz ...

data-flow analysis In computing, dataflow is a broad concept, which has various meanings depending on the application and context. In the context of software architecture, data flow relates to stream processing or reactive programming. Software architecture Dataf ...

, data

dependence analysis In compiler theory, dependence analysis produces execution-order constraints between statements/instructions. Broadly speaking, a statement ''S2'' depends on ''S1'' if ''S1'' must be executed before ''S2''. Broadly, there are two classes of depen ...

, and

array region analysis An array is a systematic arrangement of similar objects, usually in rows and columns. Things called an array include: {{TOC right Music * In twelve-tone and serial composition, the presentation of simultaneous twelve-tone sets such that the ...

. Development has ceased, although other projects can use the project's source.

The infrastructure

Its major components are the frontend for C/C++ (using GCC) and Fortran 77/90 (using the CraySoft front-end and libraries),

Interprocedural analysis Interprocedural optimization (IPO) is a collection of compiler techniques used in computer programming to improve performance in programs containing many frequently used functions of small or medium length. IPO differs from other compiler optimiz ...

(IPA), loop nest optimizer (LNO), global optimizer (WOPT), and

code generator In computing, Code generation denotes software techniques or systems that generate program code which may then be used independently of the generator system in a runtime environment. Specific articles: * Code generation (compiler), a mechanism to pr ...

(CG). Despite being initially written for a single computer architecture, Open64 has proven that it can generate efficient code for CISC,

RISC In computer engineering, a reduced instruction set computer (RISC) is a computer designed to simplify the individual instructions given to the computer to accomplish tasks. Compared to the instructions given to a complex instruction set comput ...

, and

VLIW Very long instruction word (VLIW) refers to instruction set architectures designed to exploit instruction level parallelism (ILP). Whereas conventional central processing units (CPU, processor) mostly allow programs to specify instructions to exe ...

architectures, including MIPS,

x86 x86 (also known as 80x86 or the 8086 family) is a family of complex instruction set computer (CISC) instruction set architectures initially developed by Intel based on the Intel 8086 microprocessor and its 8088 variant. The 8086 was introd ...

IA-64 IA-64 (Intel Itanium architecture) is the instruction set architecture (ISA) of the Itanium family of 64-bit Intel microprocessors. The basic ISA specification originated at Hewlett-Packard (HP), and was subsequently implemented by Intel in coll ...

ARM In human anatomy, the arm refers to the upper limb in common usage, although academically the term specifically means the upper arm between the glenohumeral joint (shoulder joint) and the elbow joint. The distal part of the upper limb between th ...

, and others.

Intermediate representation

A hierarchical

intermediate representation An intermediate representation (IR) is the data structure or code used internally by a compiler or virtual machine to represent source code. An IR is designed to be conducive to further processing, such as optimization and translation. A "good" ...

(IR) with five main levels is used in this compiler to serve as the common interface among all the frontend and backend components. This IR is named WHIRL.

Versions

The original version of Open64 that was released in 2002 was missing its very advanced

software pipelining In computer science, software pipelining is a technique used to optimize loops, in a manner that parallels hardware pipelining. Software pipelining is a type of out-of-order execution, except that the reordering is done by a compiler (or in the ...

code generator, and had only a rudimentary code generator for Itanium. The entire original MIPSPro compiler, with this code generator, is available under a commercial license as the Blackbird compiler from Reservoir Labs. Th
Showdown Paper
documents the code generator that was not included in Open64. The very advanced compiler from Tilera, for its 64-core TILE64 chip, is based on Blackbird. Open64 exists in many

forks In cutlery or kitchenware, a fork (from la, furca 'pitchfork') is a utensil, now usually made of metal, whose long handle terminates in a head that branches into several narrow and often slightly curved tines with which one can spear foods ei ...

, each of which has different features and limitations. The "classic" Open64 branch is the Open Research Compiler (ORC), which produces code only for the Itanium (IA-64), and was funded by

Intel Intel Corporation is an American multinational corporation and technology company headquartered in Santa Clara, California. It is the world's largest semiconductor chip manufacturer by revenue, and is one of the developers of the x86 seri ...

. The ORC effort ended in 2003, and the current official branch (which originated from the Intel ORC project) is managed by

Hewlett Packard The Hewlett-Packard Company, commonly shortened to Hewlett-Packard ( ) or HP, was an American multinational information technology company headquartered in Palo Alto, California. HP developed and provided a wide variety of hardware components ...

and the

University of Delaware The University of Delaware (colloquially UD or Delaware) is a public land-grant research university located in Newark, Delaware. UD is the largest university in Delaware. It offers three associate's programs, 148 bachelor's programs, 121 mas ...

's Computer Architecture and Parallel Systems Laboratory (CAPSL). Other important branches include the compilers from

Tensilica Tensilica was a company based in Silicon Valley in the semiconductor intellectual property core business. It is now a part of Cadence Design Systems. Tensilica is known for its customizable Xtensa microprocessor core. Other products include: HiF ...

and the

AMD Advanced Micro Devices, Inc. (AMD) is an American multinational semiconductor company based in Santa Clara, California, that develops computer processors and related technologies for business and consumer markets. While it initially manufactur ...

x86 Open64 Compiler Suite.

Nvidia Nvidia CorporationOfficially written as NVIDIA and stylized in its logo as VIDIA with the lowercase "n" the same height as the uppercase "VIDIA"; formerly stylized as VIDIA with a large italicized lowercase "n" on products from the mid 1990s to ...

is also using an Open64 fork to optimize code in its

CUDA CUDA (or Compute Unified Device Architecture) is a parallel computing platform and application programming interface (API) that allows software to use certain types of graphics processing units (GPUs) for general purpose processing, an approach ca ...

toolchain. Open64 is used as the backend for the HPE NonStop OS compilers on the x86-64 platform.

Open64 releases

AMD x86 Open64 releases

Current development projects

Open64 is also used in a number of research projects, such as the

Unified Parallel C Unified Parallel C (UPC) is an extension of the C programming language designed for high-performance computing on large-scale parallel machines, including those with a common global address space ( SMP and NUMA) and those with distributed memory ...

(UPC) and speculative multithreading work at various universities. The 2010 Open64 Developers Forum describes projects done at Absoft,

Chinese Academy of Sciences The Chinese Academy of Sciences (CAS); ), known by Academia Sinica in English until the 1980s, is the national academy of the People's Republic of China for natural sciences. It has historical origins in the Academia Sinica during the Republ ...

Fudan University Fudan University () is a national public research university in Shanghai, China. Fudan is a member of the C9 League, Project 985, Project 211, and the Double First Class University identified by the Ministry of Education of China. It is als ...

, HP,

National Tsing Hua University National Tsing Hua University (NTHU; ) is a public research university in Hsinchu City, Taiwan. National Tsing Hua University was first founded in Beijing. After the Chinese Civil War, the then-president of the university, Mei Yiqi, and other ...

Tsinghua University Tsinghua University (; abbreviation, abbr. THU) is a National university, national Public university, public research university in Beijing, China. The university is funded by the Ministry of Education of the People's Republic of China, Minis ...

, and

University of Houston The University of Houston (UH) is a Public university, public research university in Houston, Texas. Founded in 1927, UH is a member of the University of Houston System and the List of universities in Texas by enrollment, university in Texas ...

. The

ported Open64 to the

Loongson Loongson () is the name of a family of general-purpose, MIPS architecture-compatible microprocessors, as well as the name of the Chinese fabless company (Loongson Technology) that develops them. The processors are alternately called Godson proc ...

II platform.

has extended and productized Open64 with optimizations designed for x86 multi-core processor advancements and multi-threaded code development. AMD supports Open64 as a complementary compiler to GCC. The University of Houston's OpenUH project, which is based on Open64, released a new version of its compiler suite in November 2015.OpenUH downloads page
/ref>

References

External links

*
AMD Open64 page

The Berkeley UPC-to-C translator

OpenUH project at University of Houston
{{Software in the Public Interest C (programming language) compilers C++ compilers Compilers Fortran compilers Free compilers and interpreters 2002 software

The infrastructure

Intermediate representation

Versions

Open64 releases

AMD x86 Open64 releases

Current development projects

See also

References

External links