diff mbox series

[SPARSE,3/5] do not issue a branch to non-existent label

Message ID 20200410184918.64692-4-luc.vanoostenryck@gmail.com (mailing list archive)
State Rejected, archived
Headers show
Series detect invalid branches in the IR | expand

Commit Message

Luc Van Oostenryck April 10, 2020, 6:49 p.m. UTC 
If the label doesn't exist, the corresponding BB will never
be created and the CFG will be invalid.

So, do not issue the branch for goto to these labels.

Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
---
 linearize.c                         | 13 +++++++++++--
 validation/linear/invalid-labels0.c |  1 -
 2 files changed, 11 insertions(+), 3 deletions(-)
diff mbox series

Patch

diff --git a/linearize.c b/linearize.c
index b040d345d469..4e9f9b3693e9 100644
--- a/linearize.c
+++ b/linearize.c
@@ -2379,6 +2379,7 @@  static pseudo_t linearize_statement(struct entrypoint *ep, struct statement *stm
 	}
 
 	case STMT_GOTO: {
+		struct symbol *label;
 		struct symbol *sym;
 		struct expression *expr;
 		struct instruction *goto_ins;
@@ -2389,8 +2390,16 @@  static pseudo_t linearize_statement(struct entrypoint *ep, struct statement *stm
 		if (!bb_reachable(active))
 			break;
 
-		if (stmt->goto_label) {
-			add_goto(ep, get_bound_block(ep, stmt->goto_label));
+		label = stmt->goto_label;
+		if (label) {
+			if (!label->stmt) {
+				// do not issue a branch to non-existent labels
+				if (label->namespace == NS_LABEL)
+					break;
+				if (label->namespace == NS_NONE)
+					break;
+			}
+			add_goto(ep, get_bound_block(ep, label));
 			break;
 		}
 
diff --git a/validation/linear/invalid-labels0.c b/validation/linear/invalid-labels0.c
index ae3bf7283fb8..a15e9d434011 100644
--- a/validation/linear/invalid-labels0.c
+++ b/validation/linear/invalid-labels0.c
@@ -11,7 +11,6 @@  void bar(void)
 /*
  * check-name: invalid-labels0
  * check-command: test-linearize -Wno-decl $file
- * check-known-to-fail
  *
  * check-output-ignore
  * check-output-excludes: END