C lvalues/rvalues, objects, and values.
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},
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"fields_dict": {
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"Basic": [
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@ -9,3 +9,4 @@ title: "2024-08-12"
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- [ ] Korean (Read 1 Story)
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* Add more SET condition code checks.
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* Notes on C lvalues and rvalues, objects and values.
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@ -8,7 +8,7 @@ tags:
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## Overview
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C declarations were designed so that the declaration of an object looks like the use of the object. This isn't quite true - keywords like `volatile` and `const` only exist in declarations - but for the most part, this philosophy can be leveraged to read C declarations.
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C declarations were designed so that the **declaration** of an object looks like the use of the object. This isn't quite true - keywords like `volatile` and `const` only exist in declarations - but for the most part, this philosophy can be leveraged to read C declarations.
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## Declarators
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@ -911,4 +911,5 @@ END%%
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## Bibliography
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* Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
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* “ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
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* Van der Linden, Peter. _Expert C Programming: Deep C Secrets_. Programming Languages / C. Mountain View, Cal.: SunSoft Pr, 1994.
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@ -1,5 +1,375 @@
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---
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title: C17
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TARGET DECK: Obsidian::STEM
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FILE TAGS: c17
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tags:
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- c17
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---
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## Overview
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An **object** is a region of data storage in the execution environment, the contents of which can represent **values**. We say an object type is **complete** if there is sufficient information to determine the size of objects of that type. Otherwise we say it is **incomplete**.
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An **lvalue** is an expression (with non-`void` object type) that potentially designates an object. An **rvalue** is the "value of the expression."
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%%ANKI
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Basic
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What does an object refer to?
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Back: A region of data storage in the execution environment, the contents of which can represent values.
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Reference: “ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
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<!--ID: 1723510994830-->
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END%%
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%%ANKI
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Basic
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What does a value refer to?
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Back: The contents of an object when interpreted as having a specific type.
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Reference: “ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
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<!--ID: 1723510994835-->
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END%%
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%%ANKI
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Cloze
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A {value} refers to the contents of an {object} when interpreted as having a specific type.
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Reference: “ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
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<!--ID: 1723510994839-->
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END%%
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%%ANKI
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Basic
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Types are partitioned into what two categories?
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Back: Object types and function types.
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Reference: “ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
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<!--ID: 1723510994842-->
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END%%
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%%ANKI
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Basic
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What is an object type?
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Back: A type that describes objects.
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Reference: “ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
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<!--ID: 1723510994846-->
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END%%
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%%ANKI
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Basic
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What is a function type?
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Back: A type that describes functions.
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Reference: “ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
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<!--ID: 1723510994851-->
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END%%
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%%ANKI
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Basic
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What two parts characterize a function type?
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Back: The return type and the number/types of its parameters.
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Reference: “ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
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<!--ID: 1723510994856-->
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END%%
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%%ANKI
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Basic
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What does it mean for an object type to be complete?
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Back: There is sufficient information to determine the size of objects of that type.
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Reference: “ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
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<!--ID: 1723510994866-->
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END%%
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%%ANKI
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Basic
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What does it mean for an object type to be incomplete?
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Back: There is insufficient information to determine the size of objects of that type.
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Reference: “ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
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<!--ID: 1723510994870-->
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END%%
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%%ANKI
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Basic
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What is an lvalue?
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Back: An expression (with non-`void` object type) that potentially designates an object.
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Reference: “ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
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<!--ID: 1723510994874-->
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END%%
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%%ANKI
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Basic
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Why are lvalues named the way they are?
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Back: The name is an acronym for **l**ocator **value**.
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Reference: “ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
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<!--ID: 1723510994878-->
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END%%
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%%ANKI
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Basic
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What is an rvalue?
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Back: The value of an expression.
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Reference: “ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
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<!--ID: 1723510994881-->
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END%%
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%%ANKI
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Basic
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Why are rvalues named the way they are?
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Back: The name is an acronym for **r**ight **value**.
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Reference: “ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
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<!--ID: 1723510994886-->
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END%%
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%%ANKI
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Basic
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What object type can an lvalue *not* have?
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Back: `void`
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Reference: “ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
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<!--ID: 1723510994890-->
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END%%
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%%ANKI
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Basic
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What object type can an lvalue have?
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Back: Any object type other than `void`.
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Reference: “ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
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<!--ID: 1723510994895-->
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END%%
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%%ANKI
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Basic
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Can an lvalue designate an object?
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Back: Yes.
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Reference: “ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
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<!--ID: 1723510994900-->
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END%%
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%%ANKI
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Basic
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Can an lvalue designate a function?
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Back: No.
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Reference: “ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
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<!--ID: 1723510994907-->
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END%%
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%%ANKI
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Basic
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Is `x` an lvalue or rvalue in the following snippet?
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```c
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int x = 10;
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```
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Back: An lvalue.
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Reference: “ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
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<!--ID: 1723510994914-->
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END%%
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%%ANKI
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Basic
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Is `int` an lvalue or rvalue in the following snippet?
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```c
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int x = 10;
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```
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Back: Neither.
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Reference: “ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
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<!--ID: 1723510994920-->
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END%%
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%%ANKI
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Basic
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Is `10` an lvalue or rvalue in the following snippet?
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```c
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int x = 10;
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```
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Back: An rvalue.
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Reference: “ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
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<!--ID: 1723510994925-->
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END%%
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%%ANKI
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Basic
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*Why* is `x` an lvalue in the following?
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```c
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int x = 10;
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```
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Back: Because `x` refers to a memory location.
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Reference: “ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
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<!--ID: 1723510994932-->
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END%%
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%%ANKI
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Basic
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Is `x` an lvalue or rvalue in the following snippet?
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```c
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void x;
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```
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Back: Neither.
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Reference: “ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
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<!--ID: 1723510994939-->
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END%%
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%%ANKI
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Basic
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Is `x` an lvalue or rvalue in the following snippet?
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```c
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void *x;
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```
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Back: An lvalue.
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Reference: “ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
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<!--ID: 1723510994945-->
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END%%
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%%ANKI
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Basic
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Is `y` an lvalue or rvalue in the following snippet?
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```c
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int y = x + 10;
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```
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Back: An lvalue.
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Reference: “ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
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<!--ID: 1723510994952-->
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END%%
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%%ANKI
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Basic
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Is `x` an lvalue or rvalue in the following snippet?
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```c
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int y = x + 10;
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```
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Back: An rvalue.
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Reference: “ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
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<!--ID: 1723510994958-->
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END%%
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%%ANKI
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Basic
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In the second line, is `ptr` an lvalue or rvalue?
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```c
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int *ptr = &x;
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*ptr = 10;
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```
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Back: An lvalue.
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Reference: “ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
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<!--ID: 1723510994964-->
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END%%
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%%ANKI
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Basic
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In the second line, is `*ptr` an lvalue or rvalue?
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```c
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int *ptr = &x;
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*ptr = 10;
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```
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Back: An lvalue.
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Reference: “ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
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<!--ID: 1723510994970-->
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END%%
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%%ANKI
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Basic
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Is `getValue` an lvalue or rvalue in the following snippet?
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```c
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int getValue () {
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return 42;
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}
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```
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Back: Neither.
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Reference: “ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
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<!--ID: 1723510994975-->
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END%%
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%%ANKI
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Basic
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Is `getValue()` an lvalue or rvalue in the following snippet?
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```c
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int d = getValue();
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```
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Back: An rvalue.
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Reference: “ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
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<!--ID: 1723510994980-->
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END%%
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%%ANKI
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Basic
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*Why* is `getValue` in the following snippet neither an lvalue nor an rvalue?
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```c
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int getValue() {
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return 42;
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}
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```
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Back: The function name is just syntax. That is, it isn't an expression.
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Reference: “ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
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<!--ID: 1723510994984-->
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END%%
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%%ANKI
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Basic
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Are variables typically lvalues or rvalues?
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Back: lvalues.
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Reference: ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
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<!--ID: 1723510994988-->
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END%%
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%%ANKI
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Basic
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Are constants typically lvalues or rvalues?
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Back: rvalues.
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Reference: ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
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<!--ID: 1723510994992-->
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END%%
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%%ANKI
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Basic
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Are array elements typically lvalues or rvalues?
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Back: lvalues.
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Reference: ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
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<!--ID: 1723510994997-->
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END%%
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%%ANKI
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Basic
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Are dereferenced pointers typically lvalues or rvalues?
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Back: lvalues.
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Reference: ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
|
||||
<!--ID: 1723510995001-->
|
||||
END%%
|
||||
|
||||
%%ANKI
|
||||
Basic
|
||||
Are temporary values typically lvalues or rvalues?
|
||||
Back: rvalues.
|
||||
Reference: ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
|
||||
<!--ID: 1723510995006-->
|
||||
END%%
|
||||
|
||||
%%ANKI
|
||||
Basic
|
||||
Does `x` have complete or incomplete object type in the following?
|
||||
```c
|
||||
void x;
|
||||
```
|
||||
Back: Incomplete.
|
||||
Reference: ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
|
||||
<!--ID: 1723510995010-->
|
||||
END%%
|
||||
|
||||
%%ANKI
|
||||
Basic
|
||||
Does `x` have complete or incomplete object type in the following?
|
||||
```c
|
||||
int x;
|
||||
```
|
||||
Back: Complete.
|
||||
Reference: ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
|
||||
<!--ID: 1723510995016-->
|
||||
END%%
|
||||
|
||||
%%ANKI
|
||||
Basic
|
||||
Does `x` have complete or incomplete object type in the following?
|
||||
```c
|
||||
void *x;
|
||||
```
|
||||
Back: Complete.
|
||||
Reference: ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
|
||||
<!--ID: 1723510995023-->
|
||||
END%%
|
||||
|
||||
## Bibliography
|
||||
|
||||
* “ISO: Programming Languages - C,” April 12, 2011, [https://port70.net/~nsz/c/c11/n1570.pdf](https://port70.net/~nsz/c/c11/n1570.pdf).
|
||||
* Jens Gustedt, _Modern C_ (Shelter Island, NY: Manning Publications Co, 2020).
|
||||
|
|
@ -0,0 +1,9 @@
|
|||
---
|
||||
title: Types
|
||||
TARGET DECK: Obsidian::STEM
|
||||
FILE TAGS: c17
|
||||
tags:
|
||||
- c17
|
||||
---
|
||||
|
||||
## Overview
|
||||
|
|
@ -94,19 +94,32 @@ END%%
|
|||
|
||||
## SET
|
||||
|
||||
| Instruction | Synonym | Effect | Description |
|
||||
| ----------- | -------- | --------------------------------- | ------------------------------------ |
|
||||
| `sete` | `setz` | `D <- ZF` | Equal / zero |
|
||||
| `setne` | `setnz` | `D <- ~ZF` | Not equal / not zero |
|
||||
| `sets` | | `D <- SF` | Negative |
|
||||
| `setns` | | `D <- ~SF` | Nonnegative |
|
||||
| `setl` | `setnge` | `D <- SF ^ OF` | Less (signed `<`) |
|
||||
| `setle` | `setng` | <code>D <- (SF ^ OF) \| ZF</code> | Less or equal (signed `<=`) |
|
||||
| `setg` | `setnle` | `D <- ~(SF ^ OF) & ~ZF` | Greater (signed `>`) |
|
||||
| `setge` | `setnl` | `D <- ~(SF ^ OF)` | Greater or equal (signed `<=`) |
|
||||
| `setb` | `setnae` | `D <- CF` | Below (unsigned `<`) |
|
||||
The description of the `SET` commands apply to the case of a comparison instruction. That is, the condition codes are set according to computation `t = a - b`, where `t`, `a`, and `b` may be interpreted as signed or unsigned depending on the `SET` instruction invoked.
|
||||
|
||||
Note how the other condition code effects are easy to derive from `setl` and `setb`.
|
||||
| Instruction | Synonym | Evaluation | Description |
|
||||
| ----------- | -------- | ---------------------------- | ------------------------------ |
|
||||
| `sete` | `setz` | `ZF` | Equal / zero |
|
||||
| `setne` | `setnz` | `~ZF` | Not equal / not zero |
|
||||
| `sets` | | `SF` | Negative |
|
||||
| `setns` | | `~SF` | Nonnegative |
|
||||
| `setl` | `setnge` | `SF ^ OF` | Less (signed `<`) |
|
||||
| `setle` | `setng` | <code>(SF ^ OF) \| ZF</code> | Less or equal (signed `<=`) |
|
||||
| `setg` | `setnle` | `~(SF ^ OF) & ~ZF` | Greater (signed `>`) |
|
||||
| `setge` | `setnl` | `~(SF ^ OF)` | Greater or equal (signed `<=`) |
|
||||
| `setb` | `setnae` | `CF` | Below (unsigned `<`) |
|
||||
| `setbe` | `setna` | <code>CF \| ZF</code> | Below or equal (unsigned `<=`) |
|
||||
| `seta` | `setnbe` | `~CF & ~ZF` | Above (unsigned `>`) |
|
||||
| `setae` | `setnb` | `~CF` | Above or equal (unsigned `>=`) |
|
||||
|
||||
Note how the other condition code evaluations are easy to derive from `setl` and `setb`.
|
||||
|
||||
%%ANKI
|
||||
Basic
|
||||
What arithmetic computation is a `SET` instruction's description based on?
|
||||
Back: `t = a - b`
|
||||
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
|
||||
<!--ID: 1723413572733-->
|
||||
END%%
|
||||
|
||||
%%ANKI
|
||||
Basic
|
||||
|
|
@ -265,14 +278,6 @@ Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Program
|
|||
<!--ID: 1720992217917-->
|
||||
END%%
|
||||
|
||||
%%ANKI
|
||||
Basic
|
||||
What arithmetic computation is a `SET` instruction's interpretation of condition codes based on?
|
||||
Back: `t = a - b`
|
||||
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
|
||||
<!--ID: 1723413572733-->
|
||||
END%%
|
||||
|
||||
%%ANKI
|
||||
Basic
|
||||
What is `l` in the `setl` instruction short for?
|
||||
|
|
@ -500,6 +505,99 @@ Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Program
|
|||
<!--ID: 1723466622325-->
|
||||
END%%
|
||||
|
||||
%%ANKI
|
||||
Basic
|
||||
What is `a` in the `seta` instruction short for?
|
||||
Back: **A**bove.
|
||||
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
|
||||
<!--ID: 1723471919305-->
|
||||
END%%
|
||||
|
||||
%%ANKI
|
||||
Cloze
|
||||
{`seta`} is a synonym for {`setnbe`}.
|
||||
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
|
||||
<!--ID: 1723471919313-->
|
||||
END%%
|
||||
|
||||
%%ANKI
|
||||
Basic
|
||||
What condition code(s) does `seta` refer to?
|
||||
Back: `CF` and `ZF`.
|
||||
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
|
||||
<!--ID: 1723471919317-->
|
||||
END%%
|
||||
|
||||
%%ANKI
|
||||
Basic
|
||||
In terms of condition codes, what value does `seta` put in its specified destination?
|
||||
Back: `~CF & ~ZF`
|
||||
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
|
||||
<!--ID: 1723471919321-->
|
||||
END%%
|
||||
|
||||
%%ANKI
|
||||
Basic
|
||||
What is `ae` in the `setae` instruction short for?
|
||||
Back: **A**bove or **e**qual.
|
||||
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
|
||||
<!--ID: 1723471919325-->
|
||||
END%%
|
||||
|
||||
%%ANKI
|
||||
Cloze
|
||||
{`setae`} is a synonym for {`setnb`}.
|
||||
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
|
||||
<!--ID: 1723471919329-->
|
||||
END%%
|
||||
|
||||
%%ANKI
|
||||
Basic
|
||||
What condition code(s) does `setae` refer to?
|
||||
Back: `CF`
|
||||
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
|
||||
<!--ID: 1723471919333-->
|
||||
END%%
|
||||
|
||||
%%ANKI
|
||||
Basic
|
||||
In terms of condition codes, what value does `setae` put in its specified destination?
|
||||
Back: `~CF`
|
||||
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
|
||||
<!--ID: 1723471919338-->
|
||||
END%%
|
||||
|
||||
%%ANKI
|
||||
Basic
|
||||
What is `be` in the `setbe` instruction short for?
|
||||
Back: **B**elow or **e**qual.
|
||||
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
|
||||
<!--ID: 1723471919343-->
|
||||
END%%
|
||||
|
||||
%%ANKI
|
||||
Cloze
|
||||
{`setbe`} is a synonym for {`setna`}.
|
||||
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
|
||||
<!--ID: 1723471919349-->
|
||||
END%%
|
||||
|
||||
%%ANKI
|
||||
Basic
|
||||
What condition code(s) does `setbe` refer to?
|
||||
Back: `CF` and `ZF`.
|
||||
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
|
||||
<!--ID: 1723471919355-->
|
||||
END%%
|
||||
|
||||
%%ANKI
|
||||
Basic
|
||||
In terms of condition codes, what value does `setbe` put in its specified destination?
|
||||
Back: `CF | ZF`
|
||||
Reference: Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
|
||||
<!--ID: 1723471919361-->
|
||||
END%%
|
||||
|
||||
## Bibliography
|
||||
|
||||
* Bryant, Randal E., and David O'Hallaron. *Computer Systems: A Programmer's Perspective*. Third edition, Global edition. Always Learning. Pearson, 2016.
|
||||
|
|
|
|||
Loading…
Reference in New Issue