Improve strlen #213
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Improve strlen #213
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Replace character-by-character iteration with 4-character blocks, reducing check/increment/jump operations. Prepared for future 32-bit word loading once unsigned type support is complete.
Suppress compilation warnings that occur when characters with values > 127 are assigned to char variables on x86 platforms. Since x86(-64) treats char as signed by default and there is no 'unsigned' support at the moment, these assignments trigger signedness warnings. This commit adds a compiler option to suppress these warnings.
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The original loop had to check, increment, and jump for every single character. The new loop does this for every 4 characters.
It can load a full 32-bit word directly once 'unsigned' is implemented properly later.
Summary by Bito
This pull request enhances the performance of the strlen function in lib/c.c by processing four characters at a time, improving string handling efficiency. Minor adjustments were also made to the Makefile for clearer compiler flag settings, optimizing performance while ensuring code readability.