* Michael Matz <m...@suse.de> wrote:

> (without an built-in assembler which hopefully noone proposes).

There are disadvantages (the main one is having to implement it), but a 
built-in assembler has 
numerous advantages as well:

 - Better optimizations: for example -Os could more accurately estimate true 
instruction size.

 - Better inlining: as the examples in this thread are showing.

 - Better padding/alignment: right now GCC has no notion about the precise 
cache layout of the 
   assembly code it generates and the code alignment options it has are crude. 
It got away with 
   this so far because the x86 rule of thumb is that dense code is usually the 
right choice.

 - Better compiler performance: it would be faster as well to immediately emit 
assembly
   instructions, just like GCC's preprocessor library use speeds up compilation 
*significantly*
   instead of creating a separate preprocessor task.

 - Better future integration of assembly blocks: GCC could begin to actually 
understand the 
   assembly statements in inline asm and allow more user-friendly extensions to 
its 
   historically complex and difficult to master inline asm syntax.

I mean, it's a fact that the GNU project has *already* defined their own 
assembly syntax which 
departs from decades old platform assembly syntax - and how the assembler is 
called by the 
compiler is basically an implementation detail, not a conceptual choice. The 
random 
multi-process unidirectional assembler choice of the past should not be treated 
as orthodoxy.

Thanks,

        Ingo
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