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Re: Help : Instruction Scheduling
- From: James E Wilson <wilson at specifixinc dot com>
- To: Sachin Sonawane <sachinvs at cse dot iitb dot ac dot in>
- Cc: gcc at gcc dot gnu dot org
- Date: Thu, 10 Mar 2005 13:55:14 -0800
- Subject: Re: Help : Instruction Scheduling
- References: <Pine.LNX.4.61.0502261404510.13488@mars.cse.iitb.ac.in>
Sachin Sonawane wrote:
But I want to see the Assembly code with no-ops. How do I go for it?
Which construct in .md file or any other file do I need to set for it?
We have no support for emitting padding nops. You would have to modify
the x86 backend to emit them, and this would be a non-trivial change.
Try looking at the documentation for scheduler hooks, and try to figure
out how to emit a padding nop if we need to increment the cycle count
without scheduling any instructions.
An alternative would be to look at the scheduler dumps. Try compiling
with -O2 -da -fsched-verbose=2 and look at the .sched2 dump. It will
list every instruction scheduled and an estimate of which cycle the
compiler expects it to execute in.
--
Jim Wilson, GNU Tools Support, http://www.SpecifixInc.com