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Re: [Xen-devel] clang compilation

At 09:48 +0100 on 16 Aug (1376646500), Jan Beulich wrote:
> Yet with all of this I wonder what kind of broken assembler they're
> using - deferring the operand size from register operands should
> work consistently for all instructions or none, i.e. needing explicit
> suffixes on mul but not any of the other .

It's not just mul (see 794d4b9e85047aacfe23b852d3a03a8eff920aec in the
original clang series) but it is certainly odd that it's inconsistent
Presumably in some cases the choice is constrained by some other choice
the optimizer has already made.

Maybe one day I'll have the time to audit all the inline asm for
implicit operand sizes. :)


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