104 lines
4.2 KiB
Markdown
104 lines
4.2 KiB
Markdown
---
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title: Static Linkers
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TARGET DECK: Obsidian::STEM
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FILE TAGS: linkers::static
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tags:
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- linkers
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---
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## Overview
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To build an executable, a linker must perform two main tasks:
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1. **Symbol resolution**. The linker must associate each symbol reference with exactly one symbol definition.
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2. **Relocation**. The linker must relocate code and data sections by associating a memory location with each symbol definition, and then modifying all of the references to those symbols so that they point to this memory location.
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The linker blindly performs relocations using detailed instructions generated by the assembler called **relocation entries**.
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%%ANKI
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Basic
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According to Bryant et al., a static linker must perform what two tasks?
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Back: Symbol resolution and relocation.
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Reference: 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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<!--ID: 1733671136073-->
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END%%
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%%ANKI
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Basic
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Which of symbol resolution or relocation happens first?
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Back: Symbol resolution.
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Reference: 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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<!--ID: 1733671136078-->
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END%%
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%%ANKI
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Basic
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What is the goal of symbol resolution?
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Back: To associate each symbol reference with exactly one symbol definition.
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Reference: 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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<!--ID: 1733671136081-->
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END%%
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%%ANKI
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Basic
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What is the goal of relocation?
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Back: To assign a memory location to each symbol and update references accordingly.
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Reference: 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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<!--ID: 1733671136084-->
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END%%
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%%ANKI
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Basic
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*Why* must relocation happen after symbol resolution?
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Back: We should not assign multiple addresses to the same symbol.
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Reference: 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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<!--ID: 1733671136088-->
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END%%
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%%ANKI
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Cloze
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{Symbol resolution} associates each {symbol reference} with exactly one {symbol definition}.
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Reference: 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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<!--ID: 1733671136092-->
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END%%
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%%ANKI
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Cloze
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{Relocation} assigns a {memory location} to each symbol and {updates references} accordingly.
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Reference: 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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<!--ID: 1733671136097-->
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END%%
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%%ANKI
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Basic
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What does it mean for a linker to relocate a code and/or data section?
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Back: It associates a memory location with each symbol definition and updates references accordingly.
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Reference: 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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<!--ID: 1733671136102-->
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END%%
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%%ANKI
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Basic
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What is emitted by the assembler to help the linker relocate sections?
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Back: Relocation entries.
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Reference: 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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<!--ID: 1733671136107-->
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END%%
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%%ANKI
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Cloze
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The assembler outputs {relocation entries} to guide the linker during {relocation}.
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Reference: 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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<!--ID: 1733671136112-->
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END%%
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%%ANKI
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Cloze
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The {1:assembler} outputs relocation entries to guide the {1:linker} during relocation.
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Reference: 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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<!--ID: 1733671136117-->
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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. |