On Thu, Aug 02, 2018 at 05:30:53PM +0200, Tom de Vries wrote:
> The nvptx port can't support exceptions using sjlj, because ptx does not
> support sjlj. However, default_except_unwind_info still returns UI_SJLJ, even
> even if we configure with --disable-sjlj-exceptions, because UI_SJLJ is the
> fallback option.
>
> The reason default_except_unwind_info doesn't return UI_DWARF2 is because
> DWARF2_UNWIND_INFO is not defined in defaults.h, because
> INCOMING_RETURN_ADDR_RTX is not defined, because there's no ptx equivalent.
>
> Testcase libgomp.c++/for-15.C currently doesn't compile unless fno-exceptions
> is added because:
> - it tries to generate sjlj exception handling code, and
> - it tries to generate exception tables using label-addressed .byte sequence.
> Ptx doesn't support generating random data at a label, nor being able to
> load/write data relative to a label.
>
> This patch fixes the first problem by using UI_TARGET for nvptx.
>
> The second problem is worked around by generating all .byte sequences
> commented
> out. It would be better to have a narrower workaround, and define
> TARGET_ASM_BYTE_OP to "error: .byte unsupported " or some such.
Hopefully this part is temporary and there is some way to figure this out
later.
> This patch does not enable exceptions for nvptx, it merely allows c++ programs
> to run correctly if they do no use exception handling.
>
> Build on x86_64 with nvptx accelerator and reg-tested libgomp.
>
> OK for trunk?
You are the nvptx maintainer, so you can approve the changes yourself.
The libgomp changes are ok.
> [nvptx] Ignore c++ exceptions
>
> 2018-08-02 Tom de Vries <tdevr...@suse.de>
>
> PR target/86660
> * common/config/nvptx/nvptx-common.c (nvptx_except_unwind_info): New
> function. Return UI_TARGET unconditionally.
> (TARGET_EXCEPT_UNWIND_INFO): Redefine to nvptx_except_unwind_info.
> * config/nvptx/nvptx.c (TARGET_ASM_BYTE_OP): Emit commented out '.byte'.
>
> * testsuite/libgomp.oacc-c++/routine-1-auto.C: Remove -fno-exceptions.
> * testsuite/libgomp.oacc-c++/routine-1-template-auto.C: Same.
> * testsuite/libgomp.oacc-c++/routine-1-template-trailing-return-type.C:
> Same.
> * testsuite/libgomp.oacc-c++/routine-1-template.C: Same.
> * testsuite/libgomp.oacc-c++/routine-1-trailing-return-type.C: Same.
> * testsuite/libgomp.oacc-c-c++-common/routine-1.c: Same.
Jakub
