[PATCH, midlevel]: Convert (int)floor -> lfloor

[Bernd Schmidt]

Uros Bizjak wrote:
> 
> To enable this conversion, a little help from midlevel is needed. There 
> is already a (int)round -> lround conversion implemented in convert.c to 
> handle BUILT_IN_ROUND -> BUILT_IN_{L,LL}ROUND conversion. To implement 
> similar "floor" conversions, we need similar new gcc internal builtin 
> function, BUILT_IN_{L,LL}FLOOR.
> However, there is no lfloor() or llfloor() function in libc. To overcome 
> this problem, we look into machine instruction set and enable this 
> transformation iff appropriate  instruction is available (in addition to 
> flag_unsafe_math_optimizations). This way, we won't fall back into 
> (non-existing) library call.

Ugh.  If you have an expander it could still fail, couldn't it? 
Wouldn't it be cleaner to just add the necessary library functions to 
libgcc2?


Bernd