reland "[DebugInfo] Support to emit debugInfo for extern variables"

Commit d77ae1552fc21a9f3877f3ed7e13d631f517c825
("[DebugInfo] Support to emit debugInfo for extern variables")
added deebugInfo for extern variables for BPF target.
The commit is reverted by 891e25b02d760d0de18c7d46947913b3166047e7
as the committed tests using %clang instead of %clang_cc1 causing
test failed in certain scenarios as reported by Reid Kleckner.

This patch fixed the tests by using %clang_cc1.

Differential Revision: https://reviews.llvm.org/D71818

4 files changed, 84 insertions, 0 deletions

diff --git a/clang/test/CodeGen/debug-info-extern-basic.c b/clang/test/CodeGen/debug-info-extern-basic.c
new file mode 100644
index 00000000000..e2c90842fff
--- /dev/null
+++ b/clang/test/CodeGen/debug-info-extern-basic.c
@@ -0,0 +1,26 @@
+// RUN: %clang_cc1 -x c -debug-info-kind=limited -triple bpf-linux-gnu -emit-llvm %s -o - | FileCheck %s
+
+extern char ch;
+int test() {
+  return ch;
+}
+
+int test2() {
+  extern char ch2;
+  return ch2;
+}
+
+extern int (*foo)(int);
+int test3() {
+  return foo(0);
+}
+
+// CHECK: distinct !DIGlobalVariable(name: "ch",{{.*}} type: ![[CHART:[0-9]+]], isLocal: false, isDefinition: false
+// CHECK: distinct !DIGlobalVariable(name: "ch2",{{.*}} type: ![[CHART]], isLocal: false, isDefinition: false
+// CHECK: ![[CHART]] = !DIBasicType(name: "char", size: 8, encoding: DW_ATE_signed_char)
+
+// CHECK: distinct !DIGlobalVariable(name: "foo",{{.*}} type: ![[FUNC:[0-9]+]], isLocal: false, isDefinition: false)
+// CHECK: ![[FUNC]] = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: ![[SUB:[0-9]+]], size: 64)
+// CHECK: ![[SUB]] = !DISubroutineType(types: ![[TYPES:[0-9]+]])
+// CHECK: ![[TYPES]] = !{![[BASET:[0-9]+]], ![[BASET]]}
+// CHECK: ![[BASET]] = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
diff --git a/clang/test/CodeGen/debug-info-extern-duplicate.c b/clang/test/CodeGen/debug-info-extern-duplicate.c
new file mode 100644
index 00000000000..1c6d86f4cc0
--- /dev/null
+++ b/clang/test/CodeGen/debug-info-extern-duplicate.c
@@ -0,0 +1,10 @@
+// RUN: %clang_cc1 -x c -debug-info-kind=limited -triple bpf-linux-gnu -emit-llvm %s -o - | FileCheck %s
+
+extern char ch;
+extern char ch;
+int test() {
+  return ch;
+}
+
+// CHECK: distinct !DIGlobalVariable(name: "ch",{{.*}} type: ![[T:[0-9]+]], isLocal: false, isDefinition: false
+// CHECK-NOT: distinct !DIGlobalVariable(name: "ch"
diff --git a/clang/test/CodeGen/debug-info-extern-multi.c b/clang/test/CodeGen/debug-info-extern-multi.c
new file mode 100644
index 00000000000..6a9021d382b
--- /dev/null
+++ b/clang/test/CodeGen/debug-info-extern-multi.c
@@ -0,0 +1,22 @@
+// RUN: %clang_cc1 -x c -debug-info-kind=limited -triple bpf-linux-gnu -emit-llvm %s -o - | FileCheck %s
+
+extern char ch;
+int test() {
+  extern short sh;
+  return ch + sh;
+}
+
+extern char (*foo)(char);
+int test2() {
+  return foo(0) + ch;
+}
+
+// CHECK: distinct !DIGlobalVariable(name: "ch",{{.*}} type: ![[Tch:[0-9]+]], isLocal: false, isDefinition: false
+// CHECK: distinct !DIGlobalVariable(name: "sh",{{.*}} type: ![[Tsh:[0-9]+]], isLocal: false, isDefinition: false
+// CHECK: ![[Tsh]] = !DIBasicType(name: "short", size: 16, encoding: DW_ATE_signed)
+
+// CHECK: distinct !DIGlobalVariable(name: "foo",{{.*}} type: ![[Tptr:[0-9]+]], isLocal: false, isDefinition: false
+// ![[Tptr]] = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: ![[Tsub:[0-9]+]], size: 64)
+// ![[Tsub]] = !DISubroutineType(types: ![[Tproto:[0-9]+]])
+// ![[Tproto]] = !{![[Tch]], ![[Tch]]}
+// CHECK: ![[Tch]] = !DIBasicType(name: "char", size: 8, encoding: DW_ATE_signed_char)
diff --git a/clang/test/CodeGen/debug-info-extern-unused.c b/clang/test/CodeGen/debug-info-extern-unused.c
new file mode 100644
index 00000000000..8b89eaab27e
--- /dev/null
+++ b/clang/test/CodeGen/debug-info-extern-unused.c
@@ -0,0 +1,26 @@
+// RUN: %clang_cc1 -x c -debug-info-kind=limited -triple bpf-linux-gnu -emit-llvm %s -o - | FileCheck %s
+
+extern char ch;
+int test() {
+  return 0;
+}
+
+int test2() {
+  extern char ch2;
+  return 0;
+}
+
+extern int (*foo)(int);
+int test3() {
+  return 0;
+}
+
+int test4() {
+  extern int (*foo2)(int);
+  return 0;
+}
+
+// CHECK-NOT: distinct !DIGlobalVariable(name: "ch"
+// CHECK-NOT: distinct !DIGlobalVariable(name: "ch2"
+// CHECK-NOT: distinct !DIGlobalVariable(name: "foo"
+// CHECK-NOT: distinct !DIGlobalVariable(name: "foo2"