Hi,
This patch removes the early lowering of D AST types as GCC trees in
Target::preferPassByRef, fixing both PR12285 and PR12290.
The way that the target hook preferPassByRef is implemented, it relied
on the GCC "back-end" tree type to determine whether or not to use `ref'
ABI for D `in' parameters; e.g: prefer by value if it is expected that
the target will pass the type around in registers.
Building the GCC tree type depends on the AST type being complete - all
semantic processing is finished - but as this hook is called from the
front-end, this will not be the case for forward referenced or
self-referencing types.
The consensus in upstream is that `in' parameters should always be
implicitly `ref', but as the front-end does not yet support all types
being rvalue references, limit this just static arrays and structs.
Bootstrapped and regression tested on x86_64-linux-gnu/-m32, committed
to mainline and backported to releases/gcc-13 and releases/gcc-12.
Regards,
Iain.
---
PR d/112285
PR d/112290
gcc/d/ChangeLog:
* d-target.cc (Target::preferPassByRef): Return true for all static
array and struct types.
gcc/testsuite/ChangeLog:
* gdc.dg/pr112285.d: New test.
* gdc.dg/pr112290.d: New test.
---
gcc/d/d-target.cc | 25 +++++--------------------
gcc/testsuite/gdc.dg/pr112285.d | 13 +++++++++++++
gcc/testsuite/gdc.dg/pr112290.d | 15 +++++++++++++++
3 files changed, 33 insertions(+), 20 deletions(-)
create mode 100644 gcc/testsuite/gdc.dg/pr112285.d
create mode 100644 gcc/testsuite/gdc.dg/pr112290.d
diff --git a/gcc/d/d-target.cc b/gcc/d/d-target.cc
index b9d124422b7..9b69b0bc873 100644
--- a/gcc/d/d-target.cc
+++ b/gcc/d/d-target.cc
@@ -575,31 +575,16 @@ Target::supportsLinkerDirective (void) const
}
/* Decides whether an `in' parameter of the specified POD type PARAM_TYPE is to
- be passed by reference or by valie. This is used only when compiling with
+ be passed by reference or by value. This is used only when compiling with
`-fpreview=in' enabled. */
bool
Target::preferPassByRef (Type *param_type)
{
- if (param_type->size () == SIZE_INVALID)
+ /* See note in Target::isReturnOnStack. */
+ Type *tb = param_type->toBasetype ();
+ if (tb->size () == SIZE_INVALID)
return false;
- tree type = build_ctype (param_type);
-
- /* Prefer a `ref' if the type is an aggregate, and its size is greater than
- its alignment. */
- if (AGGREGATE_TYPE_P (type)
- && (!valid_constant_size_p (TYPE_SIZE_UNIT (type))
- || compare_tree_int (TYPE_SIZE_UNIT (type), TYPE_ALIGN (type)) > 0))
- return true;
-
- /* If the back-end is always going to pass this by invisible reference. */
- if (pass_by_reference (NULL, function_arg_info (type, true)))
- return true;
-
- /* If returning the parameter means the caller will do RVO. */
- if (targetm.calls.return_in_memory (type, NULL_TREE))
- return true;
-
- return false;
+ return (tb->ty == TY::Tstruct || tb->ty == TY::Tsarray);
}
diff --git a/gcc/testsuite/gdc.dg/pr112285.d b/gcc/testsuite/gdc.dg/pr112285.d
new file mode 100644
index 00000000000..5ca100a74a9
--- /dev/null
+++ b/gcc/testsuite/gdc.dg/pr112285.d
@@ -0,0 +1,13 @@
+// { dg-do compile }
+// { dg-additional-options "-fpreview=in" }
+struct S112285
+{
+}
+
+class C112285
+{
+ S112285 s;
+ void f112285(in C112285)
+ {
+ }
+}
diff --git a/gcc/testsuite/gdc.dg/pr112290.d b/gcc/testsuite/gdc.dg/pr112290.d
new file mode 100644
index 00000000000..7456fc21be1
--- /dev/null
+++ b/gcc/testsuite/gdc.dg/pr112290.d
@@ -0,0 +1,15 @@
+// { dg-do compile }
+// { dg-additional-options "-fpreview=in" }
+struct S112290a
+{
+ S112290b* p;
+ bool opEquals(in S112290a)
+ {
+ return p == p;
+ }
+}
+
+struct S112290b
+{
+ string s;
+}
--
2.40.1
