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Re: Can shrink-wrapping ever move prologue past an ASM statement?


On 07/07/2015 11:53 AM, Martin Jambor wrote:
Hi,

I've been asked to look into the item one of
http://permalink.gmane.org/gmane.linux.kernel/1990397 and found out
that at least shrink-wrapping happily moves prologue past an asm
statement which can be bad if the asm statement contains a call
instruction.

Am I right concluding that this is a bug?  Looking into the manual and
at requires_stack_frame_p() in shrink-wrap.c, I do not see any obvious
way of marking the asm statement as requiring the stack frame (but I
will not mind being proven wrong).  Do we want to create one, such as
only disallowing moving prologue past volatile asm statements?  Any
other ideas?
Shouldn't this be driven by dataflow?

jeff


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