[Bug c++/33661] template methods forget explicit local register asm vars
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=33661 Andrew Pinski changed: What|Removed |Added Target Milestone|--- |8.5
[Bug c++/33661] template methods forget explicit local register asm vars
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=33661 Jakub Jelinek changed: What|Removed |Added Status|NEW |RESOLVED CC||jakub at gcc dot gnu.org Resolution|--- |FIXED --- Comment #23 from Jakub Jelinek --- Fixed.
[Bug c++/33661] template methods forget explicit local register asm vars
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=33661
--- Comment #22 from CVS Commits ---
The releases/gcc-8 branch has been updated by Jakub Jelinek
:
https://gcc.gnu.org/g:712ffc0ad150aadfa5b91f493075e88fd050189f
commit r8-10878-g712ffc0ad150aadfa5b91f493075e88fd050189f
Author: Jakub Jelinek
Date: Thu Jan 28 16:13:11 2021 +0100
c++: Fix up handling of register ... asm ("...") vars in templates
[PR33661, PR98847]
As the testcase shows, for vars appearing in templates, we don't attach
the asm spec string to the pattern decls, nor pass it back to
cp_finish_decl
during instantiation.
The following patch does that.
2021-01-28 Jakub Jelinek
PR c++/33661
PR c++/98847
* decl.c (cp_finish_decl): For register vars with asmspec in
templates
call set_user_assembler_name and set DECL_HARD_REGISTER.
* pt.c (tsubst_expr): When instantiating DECL_HARD_REGISTER vars,
pass asmspec_tree to cp_finish_decl.
* g++.dg/opt/pr98847.C: New test.
(cherry picked from commit cf93f94b3498f3925895fb0bbfd4b64232b9987a)
[Bug c++/33661] template methods forget explicit local register asm vars
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=33661
--- Comment #21 from CVS Commits ---
The releases/gcc-9 branch has been updated by Jakub Jelinek
:
https://gcc.gnu.org/g:ef5db37cc4e80b229502bea7d6e2daa95ad6f805
commit r9-9412-gef5db37cc4e80b229502bea7d6e2daa95ad6f805
Author: Jakub Jelinek
Date: Thu Jan 28 16:13:11 2021 +0100
c++: Fix up handling of register ... asm ("...") vars in templates
[PR33661, PR98847]
As the testcase shows, for vars appearing in templates, we don't attach
the asm spec string to the pattern decls, nor pass it back to
cp_finish_decl
during instantiation.
The following patch does that.
2021-01-28 Jakub Jelinek
PR c++/33661
PR c++/98847
* decl.c (cp_finish_decl): For register vars with asmspec in
templates
call set_user_assembler_name and set DECL_HARD_REGISTER.
* pt.c (tsubst_expr): When instantiating DECL_HARD_REGISTER vars,
pass asmspec_tree to cp_finish_decl.
* g++.target/i386/pr98847.C: New test.
(cherry picked from commit cf93f94b3498f3925895fb0bbfd4b64232b9987a)
[Bug c++/33661] template methods forget explicit local register asm vars
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=33661 Florian Weimer changed: What|Removed |Added CC||nate at verse dot com --- Comment #20 from Florian Weimer --- *** Bug 58118 has been marked as a duplicate of this bug. ***
[Bug c++/33661] template methods forget explicit local register asm vars
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=33661
--- Comment #19 from CVS Commits ---
The releases/gcc-10 branch has been updated by Jakub Jelinek
:
https://gcc.gnu.org/g:cf93f94b3498f3925895fb0bbfd4b64232b9987a
commit r10-9323-gcf93f94b3498f3925895fb0bbfd4b64232b9987a
Author: Jakub Jelinek
Date: Thu Jan 28 16:13:11 2021 +0100
c++: Fix up handling of register ... asm ("...") vars in templates
[PR33661, PR98847]
As the testcase shows, for vars appearing in templates, we don't attach
the asm spec string to the pattern decls, nor pass it back to
cp_finish_decl
during instantiation.
The following patch does that.
2021-01-28 Jakub Jelinek
PR c++/33661
PR c++/98847
* decl.c (cp_finish_decl): For register vars with asmspec in
templates
call set_user_assembler_name and set DECL_HARD_REGISTER.
* pt.c (tsubst_expr): When instantiating DECL_HARD_REGISTER vars,
pass asmspec_tree to cp_finish_decl.
* g++.target/i386/pr98847.C: New test.
[Bug c++/33661] template methods forget explicit local register asm vars
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=33661
--- Comment #18 from CVS Commits ---
The master branch has been updated by Jakub Jelinek :
https://gcc.gnu.org/g:6bb207b468da36d9d99c63409dc4098514759c90
commit r11-6958-g6bb207b468da36d9d99c63409dc4098514759c90
Author: Jakub Jelinek
Date: Thu Jan 28 16:13:11 2021 +0100
c++: Fix up handling of register ... asm ("...") vars in templates
[PR33661, PR98847]
As the testcase shows, for vars appearing in templates, we don't attach
the asm spec string to the pattern decls, nor pass it back to
cp_finish_decl
during instantiation.
The following patch does that.
2021-01-28 Jakub Jelinek
PR c++/33661
PR c++/98847
* decl.c (cp_finish_decl): For register vars with asmspec in
templates
call set_user_assembler_name and set DECL_HARD_REGISTER.
* pt.c (tsubst_expr): When instantiating DECL_HARD_REGISTER vars,
pass asmspec_tree to cp_finish_decl.
* g++.target/i386/pr98847.C: New test.
[Bug c++/33661] template methods forget explicit local register asm vars
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=33661
Martin Papik changed:
What|Removed |Added
CC||mp8191mp at gmail dot com
--- Comment #17 from Martin Papik ---
Hello, I found a bug, which I think is a duplicate of this one, but am not 100%
sure.
Below is a minimal piece of code which triggers the bug. All versions of gcc
seem to be affected, as seen on compiler explorer,
https://godbolt.org/z/jFMj8b, which also shows a difference in gimple, the
templated version is missing the explicit naming attributes.
Is this the same bug? If so, is there some technical reason why a clear
miscompilation persists for as long as it seems to? What I mean is this, if a
bug like this persists for this long, it could be taken to mean that the bug is
too big for a casual volunteer. Would that be the case? Can someone familiar
with the code base tell me what I'd need to know to fix this, e.g. what's wrong
with the patch, is it better to fix the patch or start from scratch.
$ cat bug.cpp
#define DEMONSTRABLY_IDENTICAL \
long ret; \
register long r10 __asm__("r10") = (long)a4;\
__asm__ __volatile__ ("syscall" \
: "=a"(ret) \
: "a"(n), "D"(a1), "S"(a2), "d"(a3), "r"(r10) \
: "rcx", "r11", "memory"\
);
enum class sysnr : long {
// accept4 has enough parameters to require extra registers and trigger
the bug
accept4 = 0x120
};
static __inline long sys_01(long n, long a1, long a2, long a3, long a4)
{
DEMONSTRABLY_IDENTICAL
return ret;
}
template
RET sys_02(T1 a1, T2 a2, T3 a3, T4 a4) {
constexpr long n = (long) SYS_NR;
DEMONSTRABLY_IDENTICAL
return (RET)ret;
}
void test_01 () {
sys_01( (long)sysnr::accept4, 0xfeed01, 0xfeed02, 0xfeed03, 0xfeed04 );
}
void test_02() {
sys_02( 0xfeed01, 0xfeed02, 0xfeed03, 0xfeed04 );
}
void test_03() {
sys_02( 0xfeed01,
0xfeed02, 0xfeed03, 0xfeed04 );
}
$ g++ -std=c++11 -O1 bug.cpp -c -o bug.c
$ objdump -Cd bug.o
bug.o: file format elf64-x86-64
Disassembly of section .text:
:
0: 41 ba 04 ed fe 00 mov$0xfeed04,%r10d
6: b8 20 01 00 00 mov$0x120,%eax
b: bf 01 ed fe 00 mov$0xfeed01,%edi
10: be 02 ed fe 00 mov$0xfeed02,%esi
15: ba 03 ed fe 00 mov$0xfeed03,%edx
1a: 0f 05 syscall
1c: c3 retq
001d :
1d: b8 20 01 00 00 mov$0x120,%eax
22: bf 01 ed fe 00 mov$0xfeed01,%edi
27: be 02 ed fe 00 mov$0xfeed02,%esi
2c: ba 03 ed fe 00 mov$0xfeed03,%edx
31: 41 b8 04 ed fe 00 mov$0xfeed04,%r8d
37: 0f 05 syscall
39: c3 retq
003a :
3a: b8 20 01 00 00 mov$0x120,%eax
3f: bf 01 ed fe 00 mov$0xfeed01,%edi
44: be 02 ed fe 00 mov$0xfeed02,%esi
49: ba 03 ed fe 00 mov$0xfeed03,%edx
4e: 41 b8 04 ed fe 00 mov$0xfeed04,%r8d
54: 0f 05 syscall
56: c3 retq
[Bug c++/33661] template methods forget explicit local register asm vars
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=33661 --- Comment #16 from Guillaume Delugré --- Tested on g++ 9.1.0, the bug is still present. Is there any chance of having the Andreas' fix pushed upstream?
[Bug c++/33661] template methods forget explicit local register asm vars
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=33661
--- Comment #15 from Alexey Dobriyan ---
I can only reconfirm this bug still exists with 8.2.0 after rediscovering it
independently.
Linux system calls taking 4+ arguments can't be templatized as they require
register T3 _a3 asm("r10") = a3;
But using
"r10" (a3)
in assembly input constraints doesn't work either.
[Bug c++/33661] template methods forget explicit local register asm vars
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=33661 Andrew Pinski changed: What|Removed |Added CC||gdelugre.gcc at subvert dot techno ||logy --- Comment #14 from Andrew Pinski --- *** Bug 64951 has been marked as a duplicate of this bug. ***
