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Re: i386 define_asm_attributes question


On Tue, May 8, 2012 at 1:28 AM, Jan Hubicka <hubicka@ucw.cz> wrote:
> The idea here was originally to prevent LOOP instruction to get out of bounds.
> ASM statement even if they are single line may be arbitrary long and thus can
> run out of the limits.

Arbitrary long, but interrupted by semi-colons? From the
define_asm_attributes documentation (see
http://gcc.gnu.org/onlinedocs/gccint/Tagging-Insns.html):

"A specification for a length attribute is handled specially. The way
to compute the length of an asm insn is to multiply the length
specified in the expression define_asm_attributes by the number of
machine instructions specified in the asm statement, determined by
counting the number of semicolons and newlines in the string.
Therefore, the value of the length attribute specified in a
define_asm_attributes should be the maximum possible length of a
single machine instruction. "

Ciao!
Steven


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