I think I have read that there are plans to generate object code (e.g. ELF) directly in addition to assembly language source. If so, are there plans to support branch relaxation for targets which support long/short branch displacements? This is typically done in assemblers. thanks, bagel
On Thu, Aug 13, 2009 at 10:02 AM, Bagel<bagel99 at gmail.com> wrote:> I think I have read that there are plans to generate object code (e.g. ELF) > directly in addition to assembly language source. If so, are there plans to > support branch relaxation for targets which support long/short branch > displacements? This is typically done in assemblers.Yes, we are implementing a proper assembler on top of our existing machine information. Work on the backend side will likely start this week. - Daniel
ARM has its own pass to do this (ARMConstantIslandPass.cpp). At some point of time we'd like to rip out the branch relaxation part and make it into a target independent pass. Evan On Aug 13, 2009, at 10:02 AM, Bagel wrote:> I think I have read that there are plans to generate object code > (e.g. ELF) > directly in addition to assembly language source. If so, are there > plans to > support branch relaxation for targets which support long/short branch > displacements? This is typically done in assemblers. > > thanks, > bagel > _______________________________________________ > LLVM Developers mailing list > LLVMdev at cs.uiuc.edu http://llvm.cs.uiuc.edu > http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev
On Aug 13, 2009, at 1:08 PMPDT, Evan Cheng wrote:> ARM has its own pass to do this (ARMConstantIslandPass.cpp). At some > point of time we'd like to rip out the branch relaxation part and make > it into a target independent pass.I don't know about ripping it out, the data structures of the parts are pretty much interleaved. However, on a target without constant islands, the constant islands part won't do anything; it should be feasible to make the entire pass target independent. Right now the recognition and handling of branch instructions is ARM-specific, however.> Evan > > On Aug 13, 2009, at 10:02 AM, Bagel wrote: > >> I think I have read that there are plans to generate object code >> (e.g. ELF) >> directly in addition to assembly language source. If so, are there >> plans to >> support branch relaxation for targets which support long/short branch >> displacements? This is typically done in assemblers. >> >> thanks, >> bagel >> _______________________________________________ >> LLVM Developers mailing list >> LLVMdev at cs.uiuc.edu http://llvm.cs.uiuc.edu >> http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev > > _______________________________________________ > LLVM Developers mailing list > LLVMdev at cs.uiuc.edu http://llvm.cs.uiuc.edu > http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev