| Message ID | df0719d3-510f-fb67-cbb2-82dad7d9d9a1@suse.cz |
|---|---|
| State | New |
| Headers | show |
| Series | Mark DECL_SET_IS_OPERATOR_DELETE for user-provided delete operators. | expand |
OK. On 8/1/19 9:12 AM, Martin Liška wrote: > Hi. > > As discussed with Marc, I'm suggesting to mark user-provided > delete operators with DECL_SET_IS_OPERATOR_DELETE in order to allow > possible DCE for it. I've checked that clang can also optimize that > situation out. > > Patch can bootstrap on x86_64-linux-gnu and survives regression tests. > > Ready to be installed? > Thanks, > Martin > > gcc/cp/ChangeLog: > > 2019-07-30 Martin Liska <mliska@suse.cz> > > * decl.c (grok_op_properties): > Mark DECL_SET_IS_OPERATOR_DELETE for user-provided delete operators. > > gcc/testsuite/ChangeLog: > > 2019-07-30 Martin Liska <mliska@suse.cz> > > * g++.dg/cpp1y/new2.C: New test. > --- > gcc/cp/decl.c | 5 +++- > gcc/testsuite/g++.dg/cpp1y/new2.C | 39 +++++++++++++++++++++++++++++++ > 2 files changed, 43 insertions(+), 1 deletion(-) > create mode 100644 gcc/testsuite/g++.dg/cpp1y/new2.C > >
diff --git a/gcc/cp/decl.c b/gcc/cp/decl.c index 9fa090c8767..bc438d23db3 100644 --- a/gcc/cp/decl.c +++ b/gcc/cp/decl.c @@ -13670,7 +13670,10 @@ grok_op_properties (tree decl, bool complain) } if (op_flags & OVL_OP_FLAG_DELETE) - coerce_delete_type (decl, loc); + { + DECL_SET_IS_OPERATOR_DELETE (decl, true); + coerce_delete_type (decl, loc); + } else { DECL_SET_IS_OPERATOR_NEW (decl, true); diff --git a/gcc/testsuite/g++.dg/cpp1y/new2.C b/gcc/testsuite/g++.dg/cpp1y/new2.C new file mode 100644 index 00000000000..926e7960528 --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp1y/new2.C @@ -0,0 +1,39 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -std=c++17 -fdump-tree-cddce-details" } */ + +#include <cstdio> +#include <cstdlib> +#include <new> + +void* operator new(std::size_t sz) +{ + std::printf("global op new called, size = %zu\n", sz); + void *ptr = std::malloc(sz); + if (ptr) + return ptr; + else + throw std::bad_alloc{}; +} + +void operator delete(void* ptr) noexcept +{ + std::puts("global op delete called"); + std::free(ptr); +} + +void +new_primitive_load() { + int *x = new int; + int tmp = *x; + delete x; +} + +void +new_array_load() { + int *x = new int[10]; + int tmp = x[4]; + delete [] x; +} + +/* { dg-final { scan-tree-dump-times "Deleting : _\\d+ = operator new" 2 "cddce1"} } */ +/* { dg-final { scan-tree-dump-times "Deleting : operator delete" 2 "cddce1"} } */