JargonFile/entries/bare metal.txt

bare metal

n. 1. [common] New computer hardware, unadorned with such snares and
delusions as an operating system , an HLL , or even assembler. Commonly used
in the phrase programming on the bare metal , which refers to the arduous
work of bit bashing needed to create these basic tools for a new machine.
Real bare-metal programming involves things like building boot proms and
BIOS chips, implementing basic monitors used to test device drivers, and
writing the assemblers that will be used to write the compiler back ends
that will give the new machine a real development environment. 2.
Programming on the bare metal is also used to describe a style of
hand-hacking that relies on bit-level peculiarities of a particular hardware
design, esp. tricks for speed and space optimization that rely on crocks
such as overlapping instructions (or, as in the famous case described in The
Story of Mel' (in Appendix A), interleaving of opcodes on a magnetic drum to
minimize fetch delays due to the device's rotational latency). This sort of
thing has become rare as the relative costs of programming time and machine
resources have changed, but is still found in heavily constrained
environments such as industrial embedded systems. See Real Programmer.