On Wed, May 29, 2019 at 11:00:46AM +0100, Richard Sandiford wrote:
> Szabolcs Nagy <szabolcs.n...@arm.com> writes:
> > v2:
> > - use aarch64_simd_decl_p to check for aarch64_vector_pcs.
> > - emit the .variant_pcs directive even for local functions.
> > - don't require .variant_pcs asm support in compile only tests.
> > - add weakref tests.
> >
> > A dynamic linker with lazy binding support may need to handle vector PCS
> > function symbols specially, so an ELF symbol table marking was
> > introduced for such symbols.
> >
> > Function symbol references and definitions that follow the vector PCS
> > are marked in the generated assembly with .variant_pcs and then the
> > STO_AARCH64_VARIANT_PCS st_other flag is set on the symbol in the object
> > file. The marking is propagated to the dynamic symbol table by the
> > static linker so a dynamic linker can handle such symbols specially.
> >
> > For this to work, the assembler, the static linker and the dynamic
> > linker has to be updated on a system. Old assembler does not support
> > the new .variant_pcs directive, so a toolchain with old binutils won't
> > be able to compile code that references vector PCS symbols.
> >
> > gcc/ChangeLog:
> >
> > 2019-05-28 Szabolcs Nagy <szabolcs.n...@arm.com>
> >
> > * config/aarch64/aarch64-protos.h (aarch64_asm_output_alias): Declare.
> > (aarch64_asm_output_external): Declare.
> > * config/aarch64/aarch64.c (aarch64_asm_output_variant_pcs): New.
> > (aarch64_declare_function_name): Call aarch64_asm_output_variant_pcs.
> > (aarch64_asm_output_alias): New.
> > (aarch64_asm_output_external): New.
> > * config/aarch64/aarch64.h (ASM_OUTPUT_DEF_FROM_DECLS): Define.
> > (ASM_OUTPUT_EXTERNAL): Define.
> >
> > gcc/testsuite/ChangeLog:
> >
> > 2019-05-28 Szabolcs Nagy <szabolcs.n...@arm.com>
> >
> > * gcc.target/aarch64/pcs_attribute-2.c: New test.
> > * gcc.target/aarch64/torture/simd-abi-4.c: Check .variant_pcs support.
> > * lib/target-supports.exp (check_effective_target_aarch64_variant_pcs):
> > New.
>
> LGTM, but an AArch64 maintainer will need to approve.
OK with Richard's change suggested below.
Thanks,
James
>
> > diff --git a/gcc/testsuite/gcc.target/aarch64/torture/simd-abi-4.c
> > b/gcc/testsuite/gcc.target/aarch64/torture/simd-abi-4.c
> > index e399690f364..80ebd955e10 100644
> > --- a/gcc/testsuite/gcc.target/aarch64/torture/simd-abi-4.c
> > +++ b/gcc/testsuite/gcc.target/aarch64/torture/simd-abi-4.c
> > @@ -1,4 +1,5 @@
> > /* dg-do run */
> > +/* { dg-require-effective-target aarch64_variant_pcs } */
> > /* { dg-additional-options "-std=c99" } */
>
> Not your problem of course, but mind fixing the dg-do markup while
> you're there? It should be
>
> /* { dg-do run } */
>
> instead. As things stand, the test only gets compiled, not run.
>
> Thanks,
> Richard
