5.7.7.38 Rename-registers Option

The -frename-registers option attempts to avoid false dependencies in scheduled code by making use of registers leftover after register allocation. This optimization most benefits processors with many registers, but it can reduce the debugability of code, since variables might no longer be allocated to a “home register.”

This option is automatically enabled when using -funroll-loops.

The -fno-rename-registers form of this option does not use leftover registers. This is the default action if no option has been specified and the -funroll-loops option has not been used.