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re PR ipa/60965 (IPA: Devirtualization versus placement new)

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PR ipa/60965
	* ipa-devirt.c (get_class_context): Allow POD to change to non-POD.
	* g++.dg/ipa/devirt-32.C: New testcase.

From-SVN: r210086
This commit is contained in:
Jan Hubicka 2014-05-06 01:27:40 +02:00 • committed by Jan Hubicka
parent aaeaa9a91c
commit e400f08159
4 changed files with 44 additions and 0 deletions
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5
gcc/ChangeLog
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@ -1,3 +1,8 @@
2014-05-05 Jan Hubicka <hubicka@ucw.cz>
PR ipa/60965
* ipa-devirt.c (get_class_context): Allow POD to change to non-POD.
2014-05-05 Radovan Obradovic <robradovic@mips.com>
Tom de Vries <tom@codesourcery.com>

11
gcc/ipa-devirt.c
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@ -1137,6 +1137,17 @@ give_up:
context->outer_type = expected_type;
context->offset = 0;
context->maybe_derived_type = true;
context->maybe_in_construction = true;
/* POD can be changed to an instance of a polymorphic type by
placement new. Here we play safe and assume that any
non-polymorphic type is POD. */
if ((TREE_CODE (type) != RECORD_TYPE
|| !TYPE_BINFO (type)
|| !polymorphic_type_binfo_p (TYPE_BINFO (type)))
&& (TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST
|| (offset + tree_to_uhwi (TYPE_SIZE (expected_type)) <=
tree_to_uhwi (TYPE_SIZE (type)))))
return true;
return false;
}

5
gcc/testsuite/ChangeLog
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@ -1,3 +1,8 @@
2014-05-05 Jan Hubicka <hubicka@ucw.cz>
PR ipa/60965
* g++.dg/ipa/devirt-32.C: New testcase.
2014-05-05 Richard Biener <rguenther@suse.de>
PR middle-end/61010

23
gcc/testsuite/g++.dg/ipa/devirt-32.C Normal file
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@ -0,0 +1,23 @@
/* { dg-options "-O2 -std=c++11 -fdump-ipa-inline" } */
#include <new>
class EmbeddedObject {
public:
virtual int val() { return 2; }
};
class Container {
alignas(EmbeddedObject) char buffer[sizeof(EmbeddedObject)];
public:
EmbeddedObject *obj() { return (EmbeddedObject*)buffer; }
Container() { new (buffer) EmbeddedObject(); }
};
Container o;
int main()
{
__builtin_printf("%d\n", o.obj()->val());
}
/* { dg-final { scan-ipa-dump-not "__builtin_unreachable" "inline" } } */
/* { dg-final { cleanup-ipa-dump "inline" } } */