
	Where results make sense

Topic: Branch predication

Related Topics

Branch prediction

Suitheism

Typology

George Perle

List of Northwest Territories commissioners

Steinburg

Rameses IV

Uaboe

In the News (Sat 5 Dec 09)

Northern Trust

Marvin Harrison

Peter Chernin

Gary Locke

Match Play

Penelope Cruz

Mickey Rourke

AR Rahman

Danny Boyle

Hugh Jackman

	Branch predication - Wikipedia, the free encyclopedia
		Branch predication, not to be confused with branch prediction, is a strategy in computer architecture design for mitigating the costs usually associated with conditional branches, particularly branches to short sections of code.
		The main purpose of predication is to avoid jumps over very small sections of program code, increasing the effectiveness of pipelined execution and avoiding problems with the cache.
		Predicated instructions with different predicates can be mixed with each other and with unconditional code, allowing better instruction scheduling and so even better performance.
	en.wikipedia.org /wiki/Branch_predication (655 words)

	Branch predication -- Facts, Info, and Encyclopedia article (Site not responding. Last check: 2007-10-09)
		The basic idea is that each instruction is associated with a predicate (the word here used similarly to its usage in (additional info and facts about predicate logic) predicate logic) and that the instruction will only be executed if the predicate is true.
		Predicated instructions with different predicates can be mixed with each other and with unconditional code, allowing better (additional info and facts about instruction scheduling) instruction scheduling and so even better performance.
		The predicates themselves are stored in special purpose ((computer science) memory device that is the part of computer memory that has a specific address and that is used to hold information of a specific kind) registers.
	www.absoluteastronomy.com /encyclopedia/b/br/branch_predication.htm (728 words)

	IA-64
		Branch predication, which will be discussed later, is used to exploit as much parallelism as possible by eliminating branches at machine level.
		When the IA-64 encounters a branch statement in the source code it analyses the branch to see if it is a candidate for predication, as predication might cost more cycles that it saves.
		However, predication also has a down side - whatever the outcome of the branch, the processor executes all of the possible branches, and discards the results of the branch that is not required.
	www.fortunecity.com /skyscraper/cray/206/cad.html (2558 words)

	TABLE OF CONTENTS (Site not responding. Last check: 2007-10-09)
		Predicates, which are part of every IA-64 conditional, provide a very efficient way to “turn off” execution of a branch that is not taken, set up and exit from a loop, handle dynamic prediction and do n-way compares.
		Predication is particularly useful in applications with hard to predict branches like large database, data mining, data warehousing etc. Lacking the mechanism of predication, it is not surprising that traditional RISC architectures have had little success with Instruction-level parallelism.
		Branching takes time and since the compiler knows ahead of time what the branches are, many branches can be avoided by simply duplicating the code in the loop two, four, or even more times to reduce the number of branches and allow greater parallelism.
	www.ceng.metu.edu.tr /~e1298165 (5939 words)

	History of the PowerPC Architecture
		A preliminary branch prediction is made during this stage using a branch target address buffer.
		First, for branch stalls, the 620 uses a 256 entry, 2-way set associative branch target address table in the early fetch stage, and a 2 bit 2048-entry directed-mapped branch history table “BHT” in the dispatch stage.
		The branch prediction for the floating-point does quite well, predicting 97% of all branches correctly in execution, but it needs some enhancements for the integer case, which achieved only 89.9% accuracy.
	www.cs.pitt.edu /~alanjawi/p620.html (1130 words)

	[No title] (Site not responding. Last check: 2007-10-09)
		If the number of branches between repeated executions of a given branch is relatively prime compared to the length of the branch history register, it will take many iterations before the same predictor is used twice, despite the fact that the N branches previous to the given branch had the same history.
		When a prediction for a branch is needed, the primary BHR is used to index which set of 2^I predictors is used to predict the branch.
		Once the outcome of a branch is known, non-speculatively, a set of predictors is updated based on the outcome of the branch and then a 1(taken) or 0(not-taken) is shifted into all the BHRs the compiler specified for that branch.
	www.cs.princeton.edu /courses/archive/fall99/cs597d/restricted/obs/obs1/mv.html (748 words)

	Bertrand Russell - Wikipedia, the free encyclopedia
		Russell is generally recognised as one of the founders of analytic philosophy, indeed, even of its several branches.
		The fact that Russell made science a central part of his method and of philosophy was instrumental in making the philosophy of science a full-blooded, separate branch of philosophy and an area in which subsequent philosophers specialised.
		Moreover, he is the founder or, at the very least, the prime mover of its major branches and themes, including several versions of the philosophy of language, formal logical analysis, and the philosophy of science.
	en.wikipedia.org /wiki/Bertrand_Russell (8353 words)

	How Hardware Features in the Intel Itanium 2 Support .NET and Java
		Branch prediction is the traditional means by which processors increase the performance of branched sections of code.
		Predication is the Itanium 2 processor's ability to eliminate the performance deficits associated with mis-predicting branches by executing both branches in parallel and discarding the result of the branch that is not needed.
		Predication is a great leap forward from branch prediction, since by executing both parts of a branch, it eliminates the costs associated with mis-predicted branches.
	www.devx.com /Intel/Article/21289 (2076 words)

	BYTE.com
		When the CPU encounters a predicated branch at run time, it will begin executing the code along all destinations of the branch, exploiting as much parallelism as possible.
		Predication is a prime example of the new burden shifted onto compilers.
		Predication effectively remove s the negative impact of a branch at the machine level while preserving branch behavior.
	www.byte.com /art/9712/sec5/art1.htm (3141 words)

	REPORT
		Branches impede machine performance in that conditional branch is not resolved until the condition is resolved and the target address is calculated, and unconditional branch is not resolved until the target address is calculated.
		These parameters include the sizes of the branch prediction tables, number of address bits or history bits used, the organization of the branch history tables, and in the case of selective prediction scheme, the choice of the two predictors.
		Branch behavior of a program is a very important factor, if not the most important, to determine the performance of any branch prediction schemes.
	www.cs.ucdavis.edu /~su/Berkeley/cs252/project.html (7072 words)

	International Catholic University: 20.01 (Site not responding. Last check: 2007-10-09)
		But other branches of philosophy are more restrictive in their concerns, and that is why natural philosophy is concerned only with the causes of material substances, not of being as such.
		Predicables are referred to as modes of predication, whereas categories are referred to as modes of being.
		The next predicable, differentia, is predicated as the qualitative part of the nature of things that differ in number but also in species.
	home.comcast.net /~icuweb/c02001.htm (5744 words)

	Predication: Racing on with the Intel® Itanium® 2 Processor Performance Advantage - Intel® Software ...
		The Intel®; Itanium®; 2 processor supports Predication, an architectural feature that helps eliminate many branches which may lead to branch mispredict penalties, greatly increasing the efficiency with which the processor is able to execute branched code.
		To continue with the car race analogy from that article, Predication is essentially choosing the quickest path through a racecourse while eliminating the impact of wrong turns taken along the way.
		Predication is a feature by which branches are eliminated altogether by executing both the if and the else part in parallel and committing only those instructions in the instruction pipeline that are part of the true result of the branch.
	www.intel.com /cd/ids/developer/asmo-na/eng/76929.htm (414 words)

	Gottlob Frege
		A predicate calculus is a formal system (a formal language and a method of proof) in which one can represent valid inferences among predications, i.e., among statements in which properties are predicated of objects.
		Thus, a simple predication is analyzed in terms of falling under a concept, which in turn, is analyzed in terms of functions which map their arguments to truth values.
		In the modern predicate calculus, the symbols ‘∀’ (‘every’) and ‘∃’ (‘some’) are called the ‘universal’ and ‘existential’ quantifier, respectively, and the variable ‘x’ in the sentence ‘∀xMx’ is called a ‘quantified variable’, or ‘variable bound by the quantifier’.
	plato.stanford.edu /entries/frege (10319 words)

	Dynamic Hammock Predication for Non-predicated Instruction Set Architectures (Site not responding. Last check: 2007-10-09)
		Predicating a branch reduces the number of branches executed, eliminating the chance of branch misprediction at the cost of executing additional instructions.
		Dynamic predication dynamically predicates instruction sequences in the form of a branch hammock, concurrently executing both paths of the branch.
		A branch hammock is a short forward branch that spans a few instructions in the form of an if-then or if-then-else construct.
	systems.cs.colorado.edu /Papers/Architecture/PACT98-DynamicPredication (213 words)

	Energy Citations Database (ECD) - Energy and Energy-Related Bibliographic Citations
		One approach is to use branch prediction hardware and perform speculative execution of the instructions following an unresolved branch.
		In particular, we are interested in how using predication to remove a certain class of poorly predicted branches affects the prediction accuracy of the remaining branches.
		A variety of existing predication models for eliminating branch operations are presented, and the effect that eliminating branches has on branch prediction schemes ranging from simple prediction mechanisms to the newer more sophisticated branch predictors is studied.
	www.osti.gov /energycitations/product.biblio.jsp?osti_id=273920 (288 words)

	Real World Technologies - Interview With Intel's Compiler Team
		We have found that PGO works best on codes that contain lots of branches, status checking and other codes that don't have specific performance bottlenecks, as opposed to codes that sit in tight loops for significant amount of time.
		Predication is an architectural feature in which instructions are conditionally executed based on the setting of a Boolean register in the processor.
		This allows conditional execution, like if statements, to be based on register values instead of conditional branches, which can cause perturbations in the fetching of the instruction stream.
	www.realworldtech.com /page.cfm?ArticleID=RWT072803234425 (1228 words)

	[No title]
		No predicate is the same as the predicate AL (for always).
		Here, it is important to realize that the predicate names used for assembly coding are for the convenience of the programmer and the condition codes checked may not be immediately obvious.
		Predication is not present in many architectures, and the way you accomplish a similar task is using a special branch instruction.
	www.cs.umass.edu /~trekp/cs201/lecture_notes/lecture4.txt (658 words)

	Gottfried Wilhelm Leibniz -- Metaphysics [Internet Encyclopedia of Philosophy]
		Leibniz writes: Now it is obvious that all true predication has some foundation in the nature of things, and when a proposition is not identical, that is to say when the predicate is not expressly included in the subject, it must be virtually included in it.
		A complete concept contains within itself all the predicates that are true of the subject of which it is the concept, and these predicates are related by sufficient reasons into a vast single network of explanation.
		But every branch of the plant, every part of the animal, and every drop of its vital fluids, is another such garden, or another such pool.
	www.iep.utm.edu /l/leib-met.htm (10245 words)

	Modern Microprocessors - A 90 Minute Guide!
		And it can't afford to just wait – the processor encounters a branch every six instructions on average, and if it was to wait several cycles at every branch then most of the performance gained by using pipelining in the first place would be lost.
		Given this new predicated move instruction, two instructions have been eliminated from the code, and both were costly branches.
		Whether it's worth executing a few more instructions to avoid a branch is a tricky decision – for very small or very large blocks the decision is simple, but for medium-sized blocks there are complex trade-offs which the optimizer must consider.
	www.pattosoft.com.au /Articles/ModernMicroprocessors (10298 words)

	[No title] (Site not responding. Last check: 2007-10-09)
		Abstract: Branch prediction is the main method of providing speculative opportunities for new high performance processors, therefore the accuracy of branch prediction is becoming very important.
		Motivated by this desire to achieve high levels of branch prediction, this study examines methods of using up to 24 bits branch direction history to determine the probable outcome of the next execution of a conditional branch.
		Using profiling to train a prediction logic function achieves an average branch prediction accuracy of up to 96.9% for the six benchmarks used in this study.
	www-db.stanford.edu /TR/CSL-TR-92-553.html (89 words)

	Scale Change Log 2003-12-16 (Site not responding. Last check: 2007-10-09)
		This routine considers predicated defs to the same register to be ok and handles them appropriately.
		On the Sparc, a branch instruction is sometimes used in the calculation of a value.
		The branches caused to the spill logic to think it was ok to insert a load just before the store.
	www-ali.cs.umass.edu /Scale/ChangeLogs/CL2003-12-16.html (2392 words)

	OSNews.com
		Were it not for hazards (mostly branches), a 5 stage pipeline would peform the EXACLY THE SAME as a 50 stage pipeline at the same clock rate.
		That means every four instructions, the 20-stage CPU faces a (slim --- branch predication is 95% accurate) possibility of a 20-cycle delay, while the 10-stage CPU only faces the possibility of a 10-second delay.
		Since all 19 of the instructions behind the branch instruction was from the wrong branch target, so the 19 cycles spent on those instructions were all wasted.
	www.osnews.com /comment.php?news_id=5871&limit=no (4767 words)

	Using Hammock Graphs to Structure Programs (Site not responding. Last check: 2007-10-09)
		However, unstructured branch statements, such as jumps and goto's, render the control flow analysis difficult, time-consuming, and result in poor code generation.
		Branches are part of many programming languages and occur in legacy and maintenance code as well as in assembler, intermediate languages, and byte code.
		In the interest of predication and branch prediction, the number of control variables has been minimized, thereby allowing a limited code replication.
	csdl2.computer.org /persagen/DLAbsToc.jsp?resourcePath=/dl/trans/ts/&toc=comp/trans/ts/2004/04/e4toc.xml&DOI=10.1109/TSE.2004.1274043 (910 words)

	CATHOLIC ENCYCLOPEDIA: Aristotle
		These classes are substance, quantity, relation, action, passion (not to be understood as meaning merely a mental or psychic condition), place, time, situation, and habit (in the sense of dress).
		These doctrines, as well as the general concept of nature as dominated by design or purpose, came to be taken for granted in every philosophy of nature down to the time of Newton and Galileo, and the birth of modern physical science.
		Psychology in Aristotle's philosophy is treated as a branch of physical science.
	www.newadvent.org /cathen/01713a.htm (5735 words)

	predication - a Whatis.com definition (Site not responding. Last check: 2007-10-09)
		Predication (also called branch predication) is a process implemented in Explicitly Parallel Instruction Computing (EPIC)-based processors and their compilers to increase performance by eschewing branch prediction (a common technique used in modern processors), where a wrong guess by the processor brings a performance penalty.
		In predication, all the possible code branches are executed in parallel before the branch condition is proved.
		Intel's IA-64 architecture is based on EPIC and the first processor in the IA-64 line, the Itanium, uses predication.
	whatis.techtarget.com /definition/0,,sid9_gci214612,00.html (185 words)

	[No title] (Site not responding. Last check: 2007-10-09)
		Improved Branch Prediction Branch prediction attempts to place likely instructions to execute into an instruction cache.
		When the branch is predicted correctly, these instr are easily accessible.
		The itanium allows the compiler to communicate branch information to the processor, thus reducing the number of branch mispredictions.
	www.cs.nmsu.edu /~ngortari/work/notes_9_28_03.txt (571 words)

Try your search on: Qwika (all wikis)