UNIVERSITY OF INFORMATION TECHNOLOGY
Low-Level C Programming
ThS. Le Hoai Nghia
nghialh@uit.edu.vn
February 2009
Low-Level C Programming – p. 1/49
Goals
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Like Writing English
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Arithmetic
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Simple benchmarks
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Simple benchmarks
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C Arithmetic Trivia
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Arithmetic Lessons
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Bit Manipulation
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Bit-manipulation basics
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Advanced bit manipulation
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Faking Multiplication
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Faking Multiplication
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Faking Division
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Multi-way branches
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Nios code for if-then-else
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Nios code for switch (1)
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Nios code for switch (2)
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Computing Discrete Functions
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Computing Discrete Functions
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Function calls
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Code for foo() (unoptimized)
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Code for foo() (optimized)
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Strength Reduction
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Unoptimized array code (fragment)
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Unoptimized pointer code (fragment)
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Optimized (–O2) array code
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Optimized (–O2) pointer code
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How Rapid is Rapid?
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Double-checking
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Features in order of increasing cost
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Storage Classes in C
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Dynamic Storage Allocation
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Dynamic Storage Allocation
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Simple Dynamic Storage Allocation
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Dynamic Storage Allocation
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Simple Dynamic Storage Allocation
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Storage Classes Compared
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Memory-Mapped I/O
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Memory-Mapped I/O Access in C
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What’s With the Volatile?
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Altera I/O
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HW/SW Communication Styles
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HW/SW Communication: Interrupts
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Unix Signals
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Interrupts under Altera (1)
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Interrupts under Altera (2)
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Debugging Skills
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The Edwards Way to Debug
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