From 91418c42089cd1cbe71edcd6b2f5b26559819372 Mon Sep 17 00:00:00 2001 From: Iain Buclaw Date: Thu, 23 Jun 2022 18:24:07 +0200 Subject: d: Add `@register' attribute to compiler and library. The `@register` attribute specifies that a local or `__gshared` variable is to be given a register storage-class in the C sense of the term, and will be placed into a register named `registerName`. The variable needs to boiled down to a data type that fits the target register. It also cannot have either thread-local or `extern` storage. It is an error to take the address of a register variable. PR d/105413 gcc/d/ChangeLog: * d-attribs.cc (d_handle_register_attribute): New function. (d_langhook_attribute_table): Add register attribute. * d-codegen.cc (d_mark_addressable): Error if taken address of register variable. (build_frame_type): Error if register variable has non-local references. * d-tree.h (d_mark_addressable): Add complain parameter. * decl.cc (get_symbol_decl): Mark register varibles DECL_REGISTER. Error when register variable declared thread-local or extern. * expr.cc (ExprVisitor::visit (IndexExp *)): Don't complain about marking register vectors as addressable in an ARRAY_REF. libphobos/ChangeLog: * libdruntime/gcc/attributes.d (register): Define. gcc/testsuite/ChangeLog: * gdc.dg/attr_register1.d: New test. * gdc.dg/attr_register2.d: New test. * gdc.dg/attr_register3.d: New test. --- gcc/d/decl.cc | 24 ++++++++++++++++++++++-- 1 file changed, 22 insertions(+), 2 deletions(-) (limited to 'gcc/d/decl.cc') diff --git a/gcc/d/decl.cc b/gcc/d/decl.cc index b82e2d5..5032ae0 100644 --- a/gcc/d/decl.cc +++ b/gcc/d/decl.cc @@ -670,10 +670,14 @@ public: rest_of_decl_compilation (decl, 1, 0); } } - else if (d->isDataseg () && !(d->storage_class & STCextern)) + else if (d->isDataseg ()) { tree decl = get_symbol_decl (d); + /* Only need to build the VAR_DECL for extern declarations. */ + if (d->storage_class & STCextern) + return; + /* Duplicated VarDeclarations map to the same symbol. Check if this is the one declaration which will be emitted. */ tree ident = DECL_ASSEMBLER_NAME (decl); @@ -1343,7 +1347,11 @@ get_symbol_decl (Declaration *decl) if (decl->storage_class & STCvolatile) TREE_THIS_VOLATILE (decl->csym) = 1; - /* Likewise, so could the deprecated attribute. */ + /* Symbol was marked register. */ + if (decl->storage_class & STCregister) + DECL_REGISTER (decl->csym) = 1; + + /* Symbol was declared with deprecated attribute. */ if (decl->storage_class & STCdeprecated) TREE_DEPRECATED (decl->csym) = 1; @@ -1376,6 +1384,18 @@ get_symbol_decl (Declaration *decl) /* Apply any user attributes that may affect semantic meaning. */ apply_user_attributes (decl, decl->csym); + /* Handle any conflicts between D language attributes and compiler-recognized + * user attributes. */ + if (VAR_P (decl->csym) && DECL_HARD_REGISTER (decl->csym)) + { + if (decl->storage_class & STCextern) + error_at (make_location_t (decl->loc), "explicit register variable " + "%qs declared %", decl->toChars ()); + else if (decl->isThreadlocal ()) + error_at (make_location_t (decl->loc), "explicit register variable " + "%qs declared thread local", decl->toChars ()); + } + /* %% Probably should be a little more intelligent about setting this. */ TREE_USED (decl->csym) = 1; d_keep (decl->csym); -- cgit v1.1