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Re: basic asm and memory clobbers - Proposed solution

From: Bernd Schmidt <bschmidt at redhat dot com>
To: Segher Boessenkool <segher at kernel dot crashing dot org>, David Wohlferd <dw at LimeGreenSocks dot com>
Cc: Bernd Edlinger <bernd dot edlinger at hotmail dot de>, Andrew Haley <aph at redhat dot com>, Jeff Law <law at redhat dot com>, Joseph Myers <joseph at codesourcery dot com>, "rth at redhat dot com" <rth at redhat dot com>, Richard Earnshaw <Richard dot Earnshaw at foss dot arm dot com>, "gcc at gcc dot gnu dot org" <gcc at gcc dot gnu dot org>, "Paul_Koning at Dell dot com" <Paul_Koning at Dell dot com>, "jakub at redhat dot com" <jakub at redhat dot com>, "rth at gcc dot gnu dot org" <rth at gcc dot gnu dot org>, "pinskia at gcc dot gnu dot org" <pinskia at gcc dot gnu dot org>, Ian Lance Taylor <iant at google dot com>, Sandra Loosemore <sandra at codesourcery dot com>, Hans-Peter Nilsson <hp at bitrange dot com>
Date: Tue, 15 Dec 2015 13:52:05 +0100
Subject: Re: basic asm and memory clobbers - Proposed solution
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On 12/14/2015 09:10 AM, Segher Boessenkool wrote:

That, and adding a memory clobber degrades performance for a lot of
existing basic asm that does not expect the clobber, e.g. asm(""),
asm("#"), asm("nop"), ...

I wonder about this. People keep bringing up "a lot of existing basicasm" in general, but are there any known examples in real software?



Bernd

Follow-Ups:
- AW: basic asm and memory clobbers - Proposed solution
  - From: Bernd Edlinger
- Re: basic asm and memory clobbers - Proposed solution
  - From: Paul_Koning

References:
- Re: basic asm and memory clobbers - Proposed solution
  - From: Richard Earnshaw
- Re: basic asm and memory clobbers - Proposed solution
  - From: David Wohlferd
- Re: basic asm and memory clobbers - Proposed solution
  - From: Joseph Myers
- Re: basic asm and memory clobbers - Proposed solution
  - From: Jeff Law
- Re: basic asm and memory clobbers - Proposed solution
  - From: David Wohlferd
- Re: basic asm and memory clobbers - Proposed solution
  - From: Andrew Haley
- Re: basic asm and memory clobbers - Proposed solution
  - From: Bernd Edlinger
- Re: basic asm and memory clobbers - Proposed solution
  - From: David Wohlferd
- Re: basic asm and memory clobbers - Proposed solution
  - From: Segher Boessenkool

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