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Re: RTX costs
- From: kenner at vlsi1 dot ultra dot nyu dot edu (Richard Kenner)
- To: pocmatos at gmail dot com
- Cc: gcc at gcc dot gnu dot org
- Date: Tue, 09 Feb 2010 09:29:27 EST
- Subject: Re: RTX costs
- References: <4B71694E.70707@gmail.com>
> 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?
The latter is what they're *supposed* to be measuring, but of course it's
an approximation.