https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105018
Bug ID: 105018
Summary: [nvptx] Need better alias support
Product: gcc
Version: 12.0
Status: UNCONFIRMED
Severity: enhancement
Priority: P3
Component: target
Assignee: unassigned at gcc dot gnu.org
Reporter: vries at gcc dot gnu.org
Target Milestone: ---
We currently have alias support enabled by malias, which relies on the ptx
.alias directive.
There is a number of limitations, listed in the commit adding malias:
...
Only function aliases are supported.
Weak aliases are not supported. That is, if I disable the check in
nvptx_asm_output_def_from_decls that disallows this, a weak alias is emitted
and parsed by the driver. But the test gcc.dg/globalalias.c starts failing,
with the behaviour matching the comment about "weird behavior of AIX's .set
pseudo-op": a weak alias may resolve to different functions in different
files.
Aliases to weak symbols are not supported (see gcc.dg/localalias.c). This is
currently not prohibited by the compiler, but with the driver link we run
into: "error: Function test with .weak scope cannot be aliased".
Aliases to aliases are not supported (see libgomp.c-c++-common/pr96390.c).
This is currently not prohibited by the compiler, but with the driver link we
run into: "Internal error: alias to unknown symbol" .
Unreferenced aliases are not emitted (these can occur f.i. when inlining a
call to an alias). This avoids driver link error "Internal error: reference
to deleted section".
...
We'd like an implementation that doesn't have (all of) these limitations.
