into a single "__asm"-statement as GCC doesn't guarantee their
consecutive output even when using consecutive "__asm __volatile"-
statement for them. Remove the otherwise unnecessary "__volatile". [1]
- The inline assembler instructions used here alter the condition
codes so add them to the clobber list accordingly.
- The inline assembler instructions used here uses output operands
before all input operands are consumed so add appropriate modifiers.
Pointed out by: bde [1]
MFC after: 2 weeks