8000 [3.12] gh-109719: Fix missing jump target labels when compiler reorders cold/warm blocks (GH-109734) by miss-islington · Pull Request #109749 · python/cpython · GitHub
[go: up one dir, main page]
Skip to content

[3.12] gh-109719: Fix missing jump target labels when compiler reorders cold/warm blocks (GH-109734) #109749

8000
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Sep 24, 2023
Merged

[3.12] gh-109719: Fix missing jump target labels when compiler reorders cold/warm blocks (GH-109734) #109749

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
11 changes: 11 additions & 0 deletions Lib/test/test_compile.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1225,6 +1225,17 @@ def f():
except:
pass

def test_cold_block_moved_to_end(self):
# See gh-109719
def f():
while name:
try:
break
except:
pass
else:
1 if 1 else 1


@requires_debug_ranges()
class TestSourcePositions(unittest.TestCase):
Expand Down
1 change: 1 addition & 0 deletions Misc/NEWS.d/next/Core and Builtins/2023-09-22-13-38-17.gh-issue-109719.fx5OTz.rst
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1 @@
Fix missing jump target labels when compiler reorders cold/warm blocks.
5 changes: 5 additions & 0 deletions Python/flowgraph.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1945,6 +1945,8 @@ push_cold_blocks_to_end(cfg_builder *g, int code_flags) {
}
RETURN_IF_ERROR(mark_cold(entryblock));

int next_lbl = get_max_label(g->g_entryblock) + 1;

/* If we have a cold block with fallthrough to a warm block, add */
/* an explicit jump instead of fallthrough */
for (basicblock *b = entryblock; b != NULL; b = b->b_next) {
Expand All @@ -1953,6 +1955,9 @@ push_cold_blocks_to_end(cfg_builder *g, int code_flags) {
if (explicit_jump == NULL) {
return ERROR;
}
if (!IS_LABEL(b->b_next->b_label)) {
b->b_next->b_label.id = next_lbl++;
}
basicblock_addop(explicit_jump, JUMP, b->b_next->b_label.id, NO_LOCATION);
explicit_jump->b_cold = 1;
explicit_jump->b_next = b->b_next;
Expand Down
0