From: Richard Ball <richard.b...@arm.com>
This patch adds a new testcase and docs
for the indirect_return attribute.
gcc/ChangeLog:
* doc/extend.texi: Add AArch64 docs for indirect_return
attribute.
gcc/testsuite/ChangeLog:
* gcc.target/aarch64/indirect_return.c: New test.
Co-authored-by: Yury Khrustalev <yury.khrusta...@arm.com>
---
gcc/doc/extend.texi | 5 ++++
.../gcc.target/aarch64/indirect_return.c | 25 +++++++++++++++++++
2 files changed, 30 insertions(+)
create mode 100644 gcc/testsuite/gcc.target/aarch64/indirect_return.c
diff --git a/gcc/doc/extend.texi b/gcc/doc/extend.texi
index 42bd567119d..45e2b3ec569 100644
--- a/gcc/doc/extend.texi
+++ b/gcc/doc/extend.texi
@@ -4760,6 +4760,11 @@ Enable or disable calls to out-of-line helpers to
implement atomic operations.
This corresponds to the behavior of the command-line options
@option{-moutline-atomics} and @option{-mno-outline-atomics}.
+@cindex @code{indirect_return} function attribute, AArch64
+@item indirect_return
+Used to inform the compiler that a function may return via
+an indirect return. Adds a BTI J instruction under
@option{mbranch-protection=} bti.
+
@end table
The above target attributes can be specified as follows:
diff --git a/gcc/testsuite/gcc.target/aarch64/indirect_return.c
b/gcc/testsuite/gcc.target/aarch64/indirect_return.c
new file mode 100644
index 00000000000..f1ef56d5557
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/indirect_return.c
@@ -0,0 +1,25 @@
+/* { dg-do compile } */
+/* { dg-options "-mbranch-protection=bti" } */
+
+int __attribute((indirect_return))
+foo (int a)
+{
+ return a;
+}
+
+/*
+**func1:
+** hint 34 // bti c
+** ...
+** bl foo
+** hint 36 // bti j
+** ...
+** ret
+*/
+int
+func1 (int a, int b)
+{
+ return foo (a + b);
+}
+
+/* { dg-final { check-function-bodies "**" "" "" } } */
--
2.39.5
