Re-land r337333, "Teach Clang to emit address-significance tables.",

which was reverted in r337336.

The problem that required a revert was fixed in r337338.

Also added a missing "REQUIRES: x86-registered-target" to one of
the tests.

Original commit message:
> Teach Clang to emit address-significance tables.
>
> By default, we emit an address-significance table on all ELF
> targets when the integrated assembler is enabled. The emission of an
> address-significance table can be controlled with the -faddrsig and
> -fno-addrsig flags.
>
> Differential Revision: https://reviews.llvm.org/D48155

llvm-svn: 337339

1 files changed, 20 insertions, 0 deletions

diff --git a/clang/test/CodeGen/addrsig.c b/clang/test/CodeGen/addrsig.c
new file mode 100644
index 00000000000..d7141092bb3
--- /dev/null
+++ b/clang/test/CodeGen/addrsig.c
@@ -0,0 +1,20 @@
+// REQUIRES: x86-registered-target
+
+// RUN: %clang_cc1 -triple=x86_64-unknown-linux -S %s -faddrsig -O -o - | FileCheck --check-prefix=ADDRSIG %s
+// RUN: %clang_cc1 -triple=x86_64-unknown-linux -S %s -O -o - | FileCheck --check-prefix=NO-ADDRSIG %s
+
+// ADDRSIG: .addrsig
+// ADDRSIG: .addrsig_sym g1
+// ADDRSIG-NOT: .addrsig_sym g2
+
+// NO-ADDRSIG-NOT: .addrsig
+
+extern const int g1[], g2[];
+
+const int *f1() {
+  return g1;
+}
+
+int f2() {
+  return g2[0];
+}