The Intel reference guides are dense, but well worth spending time on, likely even if you are not writing specifically for Intel chips: http://www.intel.com/con

The Intel reference guides are dense, but well worth spending time on, likely even if you are not writing specifically for Intel chips: http://www.intel.com/content/www/us/en/processors/architectures-software-developer-manuals.html http://www.intel.com/content/www/us/en/processors/architectu... The are the source for many of Agner's excellent materials. The Software Optimization Reference Manual might be the best starting point: http://www.intel.com/content/dam/www/public/us/en/documents/manuals/64-ia-32-architectures-optimization-manual.pdf http://www.intel.com/content/dam/www/public/us/en/documents/... Intel's IACA tool is also well worth exploring: https://software.intel.com/en-us/articles/intel-architecture-code-analyzer https://software.intel.com/en-us/articles/intel-architecture... It's relatively unknown, likely due to its terrible interface and poor documentation, but once you get past that, it's invaluable for understanding how the processor actually executes the instructions you provide it.