From Jason Turner
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Summary

This episode continues the assembly language primer series, focusing on how compilers optimize arithmetic operations. Jason demonstrates the LEA (Load Effective Address) instruction, which is a powerful x86 assembly feature that efficiently combines multiple arithmetic operations in a single instruction. Using Compiler Explorer, he shows how expressions like '5 + 3 * argc' are optimized from multiple separate arithmetic steps in unoptimized code to a single LEA instruction when optimizations are enabled. The episode highlights how modern compilers leverage CPU instructions in ways that might not be obvious from the original C++ code.

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