The coverage support will under some conditions decide to split edges to
accurately report coverage. By running the test suite with/without this
edge splitting a small diff shows up, addressed by this patch, which
should catch future regressions.
Removing the edge splitting:
$ diff --git a/gcc/profile.cc b/gcc/profile.cc
--- a/gcc/profile.cc
+++ b/gcc/profile.cc
@@ -1244,19 +1244,7 @@ branch_prob (bool thunk)
Don't do that when the locuses match, so
if (blah) goto something;
is not computed twice. */
- if (last
- && gimple_has_location (last)
- && !RESERVED_LOCATION_P (e->goto_locus)
- && !single_succ_p (bb)
- && (LOCATION_FILE (e->goto_locus)
- != LOCATION_FILE (gimple_location (last))
- || (LOCATION_LINE (e->goto_locus)
- != LOCATION_LINE (gimple_location (last)))))
- {
- basic_block new_bb = split_edge (e);
- edge ne = single_succ_edge (new_bb);
- ne->goto_locus = e->goto_locus;
- }
+
if ((e->flags & (EDGE_ABNORMAL | EDGE_ABNORMAL_CALL))
&& e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun))
need_exit_edge = 1;
Assuming the .gcov files from make chec-gcc RUNTESTFLAGS=gcov.exp are
kept:
$ diff -r no-split-edge with-split-edge | grep -C 2 -E "^[<>]\s\s"
diff -r sans-split-edge/gcc/gcov-4.c.gcov with-split-edge/gcc/gcov-4.c.gcov
228c228
< -: 224: break;
---
> 1: 224: break;
231c231
< -: 227: break;
---
> #####: 227: break;
237c237
< -: 233: break;
---
> 2: 233: break;
gcc/testsuite/ChangeLog:
* g++.dg/gcov/gcov-1.C: Add line count check.
* gcc.misc-tests/gcov-4.c: Likewise.
---
gcc/testsuite/g++.dg/gcov/gcov-1.C | 8 ++++----
gcc/testsuite/gcc.misc-tests/gcov-4.c | 4 ++--
2 files changed, 6 insertions(+), 6 deletions(-)
diff --git a/gcc/testsuite/g++.dg/gcov/gcov-1.C
b/gcc/testsuite/g++.dg/gcov/gcov-1.C
index 9018b9a3a73..ee383b480a8 100644
--- a/gcc/testsuite/g++.dg/gcov/gcov-1.C
+++ b/gcc/testsuite/g++.dg/gcov/gcov-1.C
@@ -257,20 +257,20 @@ test_switch (int i, int j)
switch (i) /* count(5) */
/* branch(end) */
{
- case 1:
+ case 1: /* count(1) */
result = do_something (2); /* count(1) */
- break;
+ break; /* count(1) */
case 2:
result = do_something (1024);
break;
- case 3:
+ case 3: /* count(3) */
case 4:
/* branch(67) */
if (j == 2) /* count(3) */
/* branch(end) */
return do_something (4); /* count(1) */
result = do_something (8); /* count(2) */
- break;
+ break; /* count(2) */
default:
result = do_something (32); /* count(1) */
switch_m++; /* count(1) */
diff --git a/gcc/testsuite/gcc.misc-tests/gcov-4.c
b/gcc/testsuite/gcc.misc-tests/gcov-4.c
index 9d8ab1c1097..498d299b66b 100644
--- a/gcc/testsuite/gcc.misc-tests/gcov-4.c
+++ b/gcc/testsuite/gcc.misc-tests/gcov-4.c
@@ -221,7 +221,7 @@ test_switch (int i, int j)
{
case 1:
result = do_something (2); /* count(1) */
- break;
+ break; /* count(1) */
case 2:
result = do_something (1024);
break;
@@ -230,7 +230,7 @@ test_switch (int i, int j)
if (j == 2) /* count(3) */
return do_something (4); /* count(1) */
result = do_something (8); /* count(2) */
- break;
+ break; /* count(2) */
default:
result = do_something (32); /* count(1) */
switch_m++; /* count(1) */
--
2.34.0
