Optimize C loops with `

Short summary

Article explains how to optimize C loops with the `restrict` keyword to prevent compiler pessimization. When function pointers in loops prevent the compiler from hoisting pointer dereferences outside the loop, `restrict` allows the compiler to assume the array won't be modified externally, enabling better register allocation and fewer memory accesses. Shows concrete x86-64 assembly improvements.

• •C compilers pessimize loops containing function calls due to pointer aliasing concerns
• •The `restrict` keyword promises the compiler that the array won't be modified by function pointers
• •This allows hoisting of dereferenced values into registers, resulting in measurable assembly-level performance gains

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