[cfe-dev] preventing bitcast in generated code

[Chris Lattner]

On May 10, 2010, at 1:29 PM, Jochen Wilhelmy wrote:

> Hi!
> 
> Now I have implemented my TargetInfo which derives from clang::TargetInfo
> to define type widths and alignment, but there is no ABI lowering.
> clang still generates (in unoptimized code) a llvm.memcpy.p0i8.p0i8.i32
> to copy my struct. Is this hard coded or are there other classes I have
> to override?
> 
> By the way in TargetInfo.h there are lines like
> unsigned getBoolWidth(bool isWide = false) const { return 8; }  // FIXME
> unsigned getBoolAlign(bool isWide = false) const { return 8; }  // FIXME
> 
> Later on I'd like to define bool as 1 bit, therefore would it be possible to fix this?

No.  These are memory sizes.  Memory is always in units of bytes.

-Chris