On 5/30/24 6:28 PM, Richard Sandiford wrote:
Tejas Belagod <tejas.bela...@arm.com> writes:
Currently poly-int type structures are passed by value to OpenMP runtime
functions for shared clauses etc. This patch improves on this by passing
around poly-int structures by address to avoid copy-overhead.
gcc/ChangeLog
* omp-low.c (use_pointer_for_field): Use pointer if the OMP data
structure's field type is a poly-int.
---
gcc/omp-low.cc | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/gcc/omp-low.cc b/gcc/omp-low.cc
index 1a65229cc37..b15607f4ef5 100644
--- a/gcc/omp-low.cc
+++ b/gcc/omp-low.cc
@@ -466,7 +466,8 @@ static bool
use_pointer_for_field (tree decl, omp_context *shared_ctx)
{
if (AGGREGATE_TYPE_P (TREE_TYPE (decl))
- || TYPE_ATOMIC (TREE_TYPE (decl)))
+ || TYPE_ATOMIC (TREE_TYPE (decl))
+ || POLY_INT_CST_P (DECL_SIZE (decl)))
return true;
/* We can only use copy-in/copy-out semantics for shared variables
Thanks for the reviews.
Realise this is also true of my original patch, but:
I suppose a question here is whether this function is only ever used for
local interfaces between code generated by the same source code function,
or whether it's ABI in a more general sense.
I'm not a 100% sure, but AFAICS, 'use_pointer_for_field' seems to be
used only for local interface between source and generated functions. I
don't see any backend hooks into this or backend hooking into this
function for general ABI. Ofcourse, I'm not the expert on OMP lowering,
so it would be great to get an expert opinion on this.
If the latter, I suppose
we should make sure to handle ACLE types the same way regardless of
whether the SVE vector size is known.
When you say same way, do you mean the way SVE ABI defines the rules for
SVE types?
Thanks,
Tejas.
(At the moment, the vector size is fixed for a TU, not just a function,
but we should probably plan for relaxing that in future.)
Thanks,
Richard
