[libc] implement aarch64 sigsetjmp (#136706)
- **[libc][aarch64] implement sigsetjmp**
On top of https://github.com/llvm/llvm-project/pull/136072
See also https://github.com/llvm/llvm-project/issues/137055 for remarks
on naked attributes.
```c++
//===-- Implementation of setjmp ------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "src/setjmp/sigsetjmp.h"
#include "hdr/offsetof_macros.h"
#include "src/__support/common.h"
#include "src/__support/macros/config.h"
#include "src/setjmp/setjmp_impl.h"
#include "src/setjmp/sigsetjmp_epilogue.h"
namespace LIBC_NAMESPACE_DECL {
[[gnu::naked]]
LLVM_LIBC_FUNCTION(int, sigsetjmp, (sigjmp_buf, int)) {
asm(R"(
cbz w1, %c[setjmp]
str x30, [x0, %c[retaddr]]
str x19, [x0, %c[extra]]
mov x19, x0
bl %c[setjmp]
mov w1, w0
mov x0, x19
ldr x30, [x0, %c[retaddr]]
ldr x19, [x0, %c[extra]]
b %c[epilogue])" ::[retaddr] "i"(offsetof(__jmp_buf, sig_retaddr)),
[extra] "i"(offsetof(__jmp_buf, sig_extra)), [setjmp] "i"(setjmp),
[epilogue] "i"(sigsetjmp_epilogue)
: "x0", "x1", "x19", "x30");
}
} // namespace LIBC_NAMESPACE_DECL
```diff --git a/libc/config/linux/aarch64/entrypoints.txt b/libc/config/linux/aarch64/entrypoints.txt
index 1c27f84..66d7576 100644
--- a/libc/config/linux/aarch64/entrypoints.txt
+++ b/libc/config/linux/aarch64/entrypoints.txt
@@ -933,6 +933,8 @@
# setjmp.h entrypoints
libc.src.setjmp.longjmp
libc.src.setjmp.setjmp
+ libc.src.setjmp.siglongjmp
+ libc.src.setjmp.sigsetjmp
# stdio.h entrypoints
libc.src.stdio.clearerr
diff --git a/libc/include/llvm-libc-types/jmp_buf.h b/libc/include/llvm-libc-types/jmp_buf.h
index d1a13a3..7e7d2da 100644
--- a/libc/include/llvm-libc-types/jmp_buf.h
+++ b/libc/include/llvm-libc-types/jmp_buf.h
@@ -12,7 +12,7 @@
// TODO: implement sigjmp_buf related functions for other architectures
// Issue: https://github.com/llvm/llvm-project/issues/136358
#if defined(__linux__)
-#if defined(__i386__) || defined(__x86_64__)
+#if defined(__i386__) || defined(__x86_64__) || defined(__aarch64__)
#define __LIBC_HAS_SIGJMP_BUF
#endif
#endif
diff --git a/libc/src/setjmp/aarch64/CMakeLists.txt b/libc/src/setjmp/aarch64/CMakeLists.txt
index e0e7702..1078af8 100644
--- a/libc/src/setjmp/aarch64/CMakeLists.txt
+++ b/libc/src/setjmp/aarch64/CMakeLists.txt
@@ -26,3 +26,17 @@
libc.hdr.types.jmp_buf
${setjmp_config_options}
)
+
+add_entrypoint_object(
+ sigsetjmp
+ SRCS
+ sigsetjmp.cpp
+ HDRS
+ ../sigsetjmp.h
+ DEPENDS
+ libc.hdr.types.jmp_buf
+ libc.hdr.types.sigset_t
+ libc.hdr.offsetof_macros
+ libc.src.setjmp.sigsetjmp_epilogue
+ libc.src.setjmp.setjmp
+)
diff --git a/libc/src/setjmp/aarch64/sigsetjmp.cpp b/libc/src/setjmp/aarch64/sigsetjmp.cpp
new file mode 100644
index 0000000..734591b
--- /dev/null
+++ b/libc/src/setjmp/aarch64/sigsetjmp.cpp
@@ -0,0 +1,36 @@
+//===-- Implementation of sigsetjmp ---------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "src/setjmp/sigsetjmp.h"
+#include "hdr/offsetof_macros.h"
+#include "src/__support/common.h"
+#include "src/__support/macros/config.h"
+#include "src/setjmp/setjmp_impl.h"
+#include "src/setjmp/sigsetjmp_epilogue.h"
+
+namespace LIBC_NAMESPACE_DECL {
+[[gnu::naked]]
+LLVM_LIBC_FUNCTION(int, sigsetjmp, (sigjmp_buf, int)) {
+ asm(R"(
+ cbz w1, %c[setjmp]
+
+ str x30, [x0, %c[retaddr]]
+ str x19, [x0, %c[extra]]
+ mov x19, x0
+ bl %c[setjmp]
+
+ mov w1, w0
+ mov x0, x19
+ ldr x30, [x0, %c[retaddr]]
+ ldr x19, [x0, %c[extra]]
+ b %c[epilogue])" ::[retaddr] "i"(offsetof(__jmp_buf, sig_retaddr)),
+ [extra] "i"(offsetof(__jmp_buf, sig_extra)), [setjmp] "i"(setjmp),
+ [epilogue] "i"(sigsetjmp_epilogue)
+ : "x0", "x1", "x19", "x30");
+}
+} // namespace LIBC_NAMESPACE_DECL
