https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101357
Bug ID: 101357
Summary: the coverage of a return statement goes wrong
Product: gcc
Version: 11.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: gcov-profile
Assignee: unassigned at gcc dot gnu.org
Reporter: byone.heng at gmail dot com
CC: marxin at gcc dot gnu.org
Target Milestone: ---
$./gcc -v
Using built-in specs.
COLLECT_GCC=./gcc
COLLECT_LTO_WRAPPER=/home/x/project/gcc/build/install/libexec/gcc/x86_64-pc-linux-gnu/11.0.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: ../configure --prefix=/home/x/project/gcc/build/install
--enable-checking=release --enable-languages=c,c++ --disable-multilib
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 11.0.0 20210105 (experimental) (GCC)
$cat test.c
const int true_var = 1;
static const unsigned long int false_var = 0;
extern void abort (void);
typedef int __attribute__((vector_size (32))) m256i;
__attribute__((noinline, noclone)) void
foo (int *x, m256i *y)
{
asm volatile ("" : : "r" (x), "r" (y) : "memory");
}
__attribute__((noinline, noclone)) int
bar (int x)
{
if (x > 20)
return 24;
m256i i;
foo (__builtin_alloca (x), &i);
return 128;
}
__attribute__((noinline, noclone)) int
baz (int d0, int d1, int d2, int d3, int d4, int d5, int x)
{
if (x > 20)
return 24;
m256i i;
d0 += d1 + d2 + d3 + d4 + d5; d1 += d0;
foo (__builtin_alloca (x), &i);
if( true_var > 0 )
{
return 128;
}
}
int
main ()
{
if (bar (22) != 24 || bar (20) != 128)
abort ();
#ifdef __x86_64__
register long long r10 __asm__ ("r10") = 0xdeadbeefdeadbeefULL;
asm volatile ("" : "+r" (r10));
#endif
if (baz (0, 0, 0, 0, 0, 0, 22) != 24 || baz (0, 0, 0, 0, 0, 0, 20) != 128)
abort ();
return 0;
}
$gcc -O0 --coverage test.c;./a.out;gcov test;cat test.c.gcov
-: 5:const int true_var = 1;
-: 6:static const unsigned long int false_var = 0;
-: 7:
-: 8:extern void abort (void);
-: 9:
-: 10:typedef int __attribute__((vector_size (32))) m256i;
-: 11:
-: 12:__attribute__((noinline, noclone)) void
2: 13:foo (int *x, m256i *y)
-: 14:{
2: 15: asm volatile ("" : : "r" (x), "r" (y) : "memory");
2: 16:}
-: 17:
-: 18:__attribute__((noinline, noclone)) int
2: 19:bar (int x)
-: 20:{
2: 21: if (x > 20)
1: 22: return 24;
-: 23: m256i i;
1: 24: foo (__builtin_alloca (x), &i);
1: 25: return 128;
-: 26:}
-: 27:
-: 28:__attribute__((noinline, noclone)) int
2: 29:baz (int d0, int d1, int d2, int d3, int d4, int d5, int x)
-: 30:{
2: 31: if (x > 20)
2: 32: return 24;
-: 33: m256i i;
1: 34: d0 += d1 + d2 + d3 + d4 + d5; d1 += d0;
1: 35: foo (__builtin_alloca (x), &i);
1: 36: if( true_var > 0 )
-: 37: {
1: 38: return 128;
-: 39: }
#####: 40:}
-: 41:
-: 42:int
1: 43:main ()
-: 44:{
1: 45: if (bar (22) != 24 || bar (20) != 128)
#####: 46: abort ();
-: 47:#ifdef __x86_64__
1: 48: register long long r10 __asm__ ("r10") =
0xdeadbeefdeadbeefULL;
1: 49: asm volatile ("" : "+r" (r10));
-: 50:#endif
1: 51: if (baz (0, 0, 0, 0, 0, 0, 22) != 24 || baz (0, 0, 0, 0, 0,
0, 20) != 128)
#####: 52: abort ();
1: 53: return 0;
-: 54:}
Line 32 should be executed one time.
