Talk:Basic block

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Conservative concept[edit]

Yaronf,

Your edits are okay, but you've made the concept more conservative and blurred the idea that basic blocks are intraprocedural entities (CFG edges don't leave the procedure). Generally, we allow function calls in the middle of basic blocks, as long as we know they will return; exceptions and continuations can mess this up. If you concur I'd like to revert some of your changes.

Derrick Coetzee 02:12, 29 Feb 2004 (UTC)

Hi Derrick,
When performing static code analysis, you rarely have complete information about who's calling a certain procedure. More precisely, this is a question of whether procedure addresses are observeable externally, e.g. through a linker-generated symbol table for dynamic loading. So often you have to assume that the procedure's boundary is also the start of a basic block. You can certainly optimize across function calls, but in such cases you are optimizing across basic blocks! Dynamic :analysis is different for example in a trace cache you can have a single trace with code from different :procedures.
Also, exceptions are associated with instructions at this level, not with functions.
BTW, I used "instruction" while you're using "statement". The former may prevent confusion with high-level language statements, but in any case, the article should only use one of the terms for consistency.
Yaronf 12:15, Feb 29, 2004 (UTC)

First use of the term[edit]

The material on this page is fine, but it would be nice if it referenced the earliest use of "basic block" (that I know if) which is J. Backus 1957 paper cited in the (current as of 2010-03-04) footnote 7 of http://en.wikipedia.org/wiki/Fortran . Anyone feel responsible for this page? —Preceding unsigned comment added by 75.18.168.242 (talk) 22:34, 4 March 2010 (UTC)

Clarifications[edit]

The code may be source code, assembly code or some other sequence of instructions.

Well... Assembly code is just a special case of source code, isn't it? I suggest to remove that sentence, and add source code at the very beginning of the article.

"dominates", or always executes before

The or gives the impression it's an alternative: either it's dominating, or it executes before. If I understand correctly the topics, it's just a rephrasing. I suggest to replace or with i.e. or parentheses to make that clear.

--MathsPoetry (talk) 02:03, 11 September 2011 (UTC)