// single-predecessors chain from the current insertion point.
llvm::BasicBlock *StoreBB = store->getParent();
llvm::BasicBlock *IP = CGF.Builder.GetInsertBlock();
+ llvm::SmallPtrSet<llvm::BasicBlock *, 4> SeenBBs;
while (IP != StoreBB) {
- if (!(IP = IP->getSinglePredecessor()))
+ if (!SeenBBs.insert(IP).second || !(IP = IP->getSinglePredecessor()))
return nullptr;
}
--- /dev/null
+// NOTE: Assertions have been autogenerated by utils/update_cc_test_checks.py UTC_ARGS: --version 2
+// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -S -emit-llvm %s -o - | FileCheck %s
+
+// Test for PR62830 where there are 2 infinite cycles using goto. Make sure
+// clang codegen doesn't hang.
+int a;
+
+// CHECK-LABEL: define dso_local i32 @main
+// CHECK-SAME: () #[[ATTR0:[0-9]+]] {
+// CHECK-NEXT: entry:
+// CHECK-NEXT: [[RETVAL:%.*]] = alloca i32, align 4
+// CHECK-NEXT: store i32 0, ptr [[RETVAL]], align 4
+// CHECK-NEXT: br label [[L1:%.*]]
+// CHECK: L1:
+// CHECK-NEXT: br label [[L1]]
+// CHECK: L2:
+// CHECK-NEXT: [[TMP0:%.*]] = load i32, ptr @a, align 4
+// CHECK-NEXT: [[TOBOOL:%.*]] = icmp ne i32 [[TMP0]], 0
+// CHECK-NEXT: br i1 [[TOBOOL]], label [[IF_END:%.*]], label [[IF_THEN:%.*]]
+// CHECK: if.then:
+// CHECK-NEXT: br label [[L2:%.*]]
+// CHECK: if.end:
+// CHECK-NEXT: [[TMP1:%.*]] = load i32, ptr [[RETVAL]], align 4
+// CHECK-NEXT: ret i32 [[TMP1]]
+//
+int main() {
+L1:
+ goto L1;
+
+L2:
+ if (!a)
+ goto L2;
+}