gdb: LoongArch: Handle special struct in dummy call
When execute the following command on LoongArch:
make check-gdb TESTS="gdb.base/infcall-nested-structs-c++.exp"
there exist some failed testcases:
=== gdb Summary ===
# of expected passes 5533
# of unexpected failures 367
The root cause is related with a struct containing floating-point
members as function argument or return value for a dummy call.
(1) Structure consists of one floating-point member within FRLEN bits
wide, it is passed in an FAR if available.
(2) Structure consists of two floating-point members both within FRLEN
bits wide, it is passed in two FARs if available.
(3) Structure consists of one integer member within GRLEN bits wide and
one floating-point member within FRLEN bits wide, it is passed in a
GAR and an FAR if available.
Note that in the above cases, empty structure or union members are also
ignored even in C++.
Here is a simple test on LoongArch:
loongson@bogon:~$ cat test.c
#include<stdio.h>
struct test {
long a;
double b __attribute__((aligned(16)));
};
struct test val = { 88, 99.99 };
int check_arg_struct (struct test arg)
{
printf("arg.a = %ld\n", arg.a);
printf("arg.b = %f\n", arg.b);
printf("sizeof(val) = %d\n", sizeof(val));
return 1;
}
int main()
{
check_arg_struct (val);
return 0;
}
loongson@bogon:~$ gcc -g test.c -o test
loongson@bogon:~$ ./test
arg.a = 88
arg.b = 99.990000
sizeof(val) = 32
Before:
loongson@bogon:~$ gdb test
...
(gdb) start
...
Temporary breakpoint 1, main () at test.c:19
19 check_arg_struct (val);
(gdb) p check_arg_struct (val)
arg.a = 140737488286128
arg.b = -nan
sizeof(val) = 32
$1 = 1
...
After:
loongson@bogon:~$ gdb test
...
(gdb) start
...
Temporary breakpoint 1, main () at test.c:19
19 check_arg_struct (val);
(gdb) p check_arg_struct (val)
arg.a = 88
arg.b = 99.990000
sizeof(val) = 32
$1 = 1
...
With this patch, there are no failed testcases:
make check-gdb TESTS="gdb.base/infcall-nested-structs-c++.exp"
=== gdb Summary ===
# of expected passes 5900
Signed-off-by: Hui Li <lihui@loongson.cn>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
1 file changed
