RTX costs

[Paulo J. Matos]

Hi all,

After reading the internal docs about rtx_costs I am left wondering what 
they exactly are estimating.
- Are they estimating in the beginning of expand how many insns will be 
generated from a particular insn until the assembler is generated?
- or Are they estimating how many assembler instructions will be 
generated for a particular insn?
- or something else?

If someone could clear this up, I would be happy. :)

Thanks,

Paulo Matos