[llvm-commits] [llvm] r73095 - in /llvm/trunk: include/llvm/Target/TargetMachine.h include/llvm/Target/TargetOptions.h lib/Target/ARM/ARMCallingConv.td lib/Target/ARM/ARMISelDAGToDAG.cpp lib/Target/ARM/ARMISelLowering.cpp lib/Target/ARM/ARMRegist

[Bob Wilson]

On Jun 11, 2009, at 11:52 AM, Evan Cheng wrote:
>
> On Jun 11, 2009, at 11:32 AM, Chris Lattner wrote:
>>
>> Why not put this into the target triple?  Major ABI issues like this
>> seem like they belong in the triple.
>
> It's not always clear what information we want to encode in triplet.
> In this case, it seems reasonable to encode float abi in the triplet.
> But how do we want encode this? Do we want to use it to toggle fp abi
> for any target, e.g. arm-apple-darwin-apcs?

Since target triples are a GNU thing, it would be a good idea to be  
compatible with GCC on this.  I know that for the base AAPCS ABI GCC  
uses an "eabi" suffix on the OS portion of the triple, e.g., arm-linux- 
gnueabi.

When I last worked on GCC, it had no support for the "hardfloat" AAPCS  
ABI, but I heard that it was added since then.  Does anyone know if  
GCC uses something in the triple ("eabi-hardfloat" suffix??) to  
indicate this?

Since this fp ABI is an extension of AAPCS, it would only make sense  
to allow toggling something in the target triple for targets that use  
AAPCS (not Darwin).