PL.8
'''{{Infobox programming language
| name = PL.8
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| designer = IBM
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}}'''{{Use dmy dates|date=October 2024}}{{Use American English|date=October 2024}}
PL.8 is a dialect of PL/I developed by IBM Research in the 1970s by the compiler group, under Martin Hopkins, within a major research program that led to the IBM RISC architecture.{{cite journal| url=https://www.cis.upenn.edu/~milom/cis501-Fall11/papers/cocke-RISC.pdf | title=The evolution of RISC technology at IBM| last=Cocke| first=John|author2=Markstein, V. |date=January 1990| journal=IBM Journal of Research & Development| volume=34| issue=1| pages=4–11| publisher=IBM| accessdate=2008-03-06| doi=10.1147/rd.341.0004}} It was so-called because it was about 80% of PL/I.{{Clarify|reason=so called what?|date=October 2024}} Written in PL/I and bootstrapped via the PL/I Optimizing compiler, it was an alternative to PL/S for system programming, compiling initially to an intermediate machine-independent language with symbolic registers and machine-like operations.The compiler is described in: {{cite journal |title=The 801 Minicomputer |author=George Radin |author-link=George Radin |date=May 1983 |journal=IBM Journal of Research and Development |volume=27 |issue=3 |pages=237–246 |doi=10.1147/rd.273.0237}} It applied machine-independent program optimization techniques to this intermediate language to produce exceptionally good object code. The intermediate language was mapped by the back-end to the target machine's register architecture and instruction set. Back-ends were written for IBM 801, S/370, Motorola 68000,{{cite journal|journal=SIGPLAN Notices|volume=17|issue=6|url=http://rsim.cs.illinois.edu/arch/qual_papers/compilers/auslander82.pdf|title=An Overview of the PL.8 Compiler|author1=Marc Auslander|author-link=Marc Auslander|author2=Martin Hopkins|date=June 1982}}{{cite book|url=https://books.google.com/books?id=hOdAStd3mR4C&pg=PA44|title=Computer Wars: The Post-IBM World|page=44|author1=Charles H. Ferguson|author2=Charles R. Morris|year=1993|publisher=Beard Books |isbn=978-1-58798-139-5}} and POWER/PowerPC.{{citation needed|date=November 2015}}
Use
A version was used on IBM mainframes as a development tool for software that was being designed for the IBM AS/400, as well as to write the "i370" internal code for the "Capitol" chipset used in the IBM 9377 processor and some ES/9370 models{{cite journal | last1 = Maergner | first1 = Juergen | last2 = Schwermer | first2 = Hartmut R. | title = I370 - a new dimension of microprogramming | journal = ACM SIGMICRO Newsletter | date = September 1988 | volume = 19 | issue = 3 | pages = 24–31 | issn = 1050-916X | doi = 10.1145/62185.62189 | pmid = | s2cid = 2068407 | url = }}{{cite book|title=The Design of a Microprocessor|date=6 December 2012|editor=Wilhelm Spruth|isbn=978-3-642-74918-6|publisher=Springer-Verlag|section=7.2 High Level Microprogramming in I370|url=https://books.google.com/books?id=0YmqCAAAQBAJ&pg=PA303}} and the millicode for S/390 and z/Architecture processors.{{cite journal|title=The GNU 64-bit PL8 compiler: Toward an open standard environment for firmware development|last1=Gellerich|first1=W.|last2=Hendel|first2=T.|last3=Land|first3=R.|last4=Lehmann|first4=H.|last5=Mueller|first5=M.|last6=Oden|first6=P.H.|last7=Penner|first7=H.|journal=IBM Journal of Research and Development|volume=48|issue=3.4|date=May 2004|doi=10.1147/rd.483.0543|pages=543–556}}
References
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