Hard Register Constraints
Similar to register asm but still distinct, hard register constraints are another way to force operands of inline asm into specific machine registers. In this talk we will have a brief look at hard register constraints and compare them to register asm. We will look at how to use them, how they might help write more robust code, their current (implementation) limitations, practical experiments, and have a lookout for improvements.
Stefan Schulze Frielinghaus
IBMer primarily working on the GNU Compiler Collection for Linux on Z.