On Wed, May 4, 2011 at 4:51 AM, David Edelsohn <dje....@gmail.com> wrote: > On Tue, May 3, 2011 at 5:27 PM, Michael Meissner > <meiss...@linux.vnet.ibm.com> wrote: >> When I added VSX support to the powerpc, I overlooked passing and return >> V2DImode arguments, since the only machine operation that supports V2DI is >> vector floating point conversion. Consequentally, V2DI types were passed and >> returned in GPRs instead of the vector registers on power7. >> >> This patch fixes that so that V2DImode values are passed and returned like >> other vector types. >> >> I did a bootstrap and make check with no regressions, comparing it to a build >> without the patch. I also wrote a program that passed and returned every >> single type, and I compared the assembly ouptut. With the exception of >> functions that return or are passed V2DI arguments, the code is identical. I >> tested: >> >> -m64 (implies -mabi=altivec) >> -m32 -mabi=altivec >> -m32 -mabi=no-altivec (no difference here) >> >> Is this patch ok to install? I will also want to install it in the 4.6 and >> possibly 4.5 trees as well. >> >> [gcc] >> 2011-05-03 Michael Meissner <meiss...@linux.vnet.ibm.com> >> >> PR target/48857 >> * config/rs6000/rs6000.h (VSX_SCALAR_MODE): Delete. >> (VSX_MODE): Ditto. >> (VSX_MOVE_MODE): Ditto. >> (ALTIVEC_OR_VSX_VECTOR_MODE): New macro, combine all Altivec and >> VSX vector types. Add V2DImode. >> (HARD_REGNO_CALLER_SAVE_MODE): Use it instead of >> ALTIVEC_VECTOR_MODE and VSX_VECTOR_MODE calls. >> (MODES_TIEABLE_P): Ditto. >> >> * config/rs6000/rs6000.c (rs6000_emit_move): Use >> ALTIVEC_OR_VSX_MODE instead of ALTIVEC_VECTOR_MODE and >> VSX_VECTOR_MODE. >> (init_cumulative_args): Ditto. >> (rs6000_function_arg_boundary): Ditto. >> (rs6000_function_arg_advance_1): Ditto. >> (rs6000_function_arg): Ditto. >> (rs6000_function_ok_for_sibcall): Ditto. >> (emit_frame_save): Ditto. >> (rs6000_function_value): Ditto. >> (rs6000_libcall_value): Ditto. >> >> [gcc/testsuite] >> 2011-05-03 Michael Meissner <meiss...@linux.vnet.ibm.com> >> >> PR target/48857 >> * gcc.target/powerpc/pr48857.c: New file, make sure V2DI arguments >> are passed and returned in vector registers. > > What does this do to the ABI? Haven't we now broken the ABI and > broken backwards compatibility?
It at least looks like so. You need to add appropriate changes.html entries to all branches you apply this patch to. I suppose the new version matches what XLC does? Richard. > - David >
