[libc-commits] [libc] Reland "[libc] build fix for sigsetjmp (#137047)" (PR #137214)
Schrodinger ZHU Yifan via libc-commits
libc-commits at lists.llvm.org
Tue Apr 29 05:55:16 PDT 2025
https://github.com/SchrodingerZhu updated https://github.com/llvm/llvm-project/pull/137214
>From 3ef0ab8c752dcd3275e6f408d65a573bd92e9a01 Mon Sep 17 00:00:00 2001
From: Schrodinger ZHU Yifan <i at zhuyi.fan>
Date: Thu, 24 Apr 2025 13:02:09 -0400
Subject: [PATCH 1/5] Revert "Revert "[libc] build fix for sigsetjmp (#137047)"
(#137077)"
This reverts commit 0d00b6bc3b459122de47d16c5153887063f4ea4b.
---
libc/config/linux/x86_64/entrypoints.txt | 2 +
libc/hdr/CMakeLists.txt | 9 ++
libc/hdr/offsetof_macros.h | 23 +++++
libc/include/llvm-libc-types/CMakeLists.txt | 2 +-
libc/include/llvm-libc-types/jmp_buf.h | 15 ++++
libc/include/setjmp.yaml | 16 ++++
libc/src/setjmp/CMakeLists.txt | 27 ++++++
libc/src/setjmp/linux/CMakeLists.txt | 12 +++
libc/src/setjmp/linux/sigsetjmp_epilogue.cpp | 25 ++++++
libc/src/setjmp/setjmp_impl.h | 3 +-
libc/src/setjmp/siglongjmp.cpp | 23 +++++
libc/src/setjmp/siglongjmp.h | 25 ++++++
libc/src/setjmp/sigsetjmp.h | 26 ++++++
libc/src/setjmp/sigsetjmp_epilogue.h | 19 +++++
libc/src/setjmp/x86_64/CMakeLists.txt | 20 +++--
libc/src/setjmp/x86_64/setjmp.cpp | 2 +-
libc/src/setjmp/x86_64/sigsetjmp.cpp | 68 +++++++++++++++
libc/test/src/setjmp/CMakeLists.txt | 17 ++++
libc/test/src/setjmp/sigsetjmp_test.cpp | 88 ++++++++++++++++++++
19 files changed, 414 insertions(+), 8 deletions(-)
create mode 100644 libc/hdr/offsetof_macros.h
create mode 100644 libc/src/setjmp/linux/CMakeLists.txt
create mode 100644 libc/src/setjmp/linux/sigsetjmp_epilogue.cpp
create mode 100644 libc/src/setjmp/siglongjmp.cpp
create mode 100644 libc/src/setjmp/siglongjmp.h
create mode 100644 libc/src/setjmp/sigsetjmp.h
create mode 100644 libc/src/setjmp/sigsetjmp_epilogue.h
create mode 100644 libc/src/setjmp/x86_64/sigsetjmp.cpp
create mode 100644 libc/test/src/setjmp/sigsetjmp_test.cpp
diff --git a/libc/config/linux/x86_64/entrypoints.txt b/libc/config/linux/x86_64/entrypoints.txt
index 73dfeae1a2c94..e3a96da615056 100644
--- a/libc/config/linux/x86_64/entrypoints.txt
+++ b/libc/config/linux/x86_64/entrypoints.txt
@@ -1049,6 +1049,8 @@ if(LLVM_LIBC_FULL_BUILD)
# 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/hdr/CMakeLists.txt b/libc/hdr/CMakeLists.txt
index db2dac9ff2822..209fcb965242f 100644
--- a/libc/hdr/CMakeLists.txt
+++ b/libc/hdr/CMakeLists.txt
@@ -223,5 +223,14 @@ add_proxy_header_library(
libc.include.wchar
)
+# offsetof is a macro inside compiler resource header stddef.h
+add_proxy_header_library(
+ offsetof_macros
+ HDRS
+ offsetof_macros.h
+ FULL_BUILD_DEPENDS
+ libc.include.llvm-libc-macros.offsetof_macro
+)
+
add_subdirectory(types)
add_subdirectory(func)
diff --git a/libc/hdr/offsetof_macros.h b/libc/hdr/offsetof_macros.h
new file mode 100644
index 0000000000000..42e853ffa92e5
--- /dev/null
+++ b/libc/hdr/offsetof_macros.h
@@ -0,0 +1,23 @@
+//===-- Definition of macros for offsetof ---------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_HDR_OFFSETOF_MACROS_H
+#define LLVM_LIBC_HDR_OFFSETOF_MACROS_H
+
+#ifdef LIBC_FULL_BUILD
+
+#include "include/llvm-libc-macros/offsetof-macro.h"
+
+#else // Overlay mode
+
+#define __need_offsetof
+#include <stddef.h>
+
+#endif // LLVM_LIBC_FULL_BUILD
+
+#endif // LLVM_LIBC_HDR_OFFSETOF_MACROS_H
diff --git a/libc/include/llvm-libc-types/CMakeLists.txt b/libc/include/llvm-libc-types/CMakeLists.txt
index 861b983b34219..26a3ed06b6f05 100644
--- a/libc/include/llvm-libc-types/CMakeLists.txt
+++ b/libc/include/llvm-libc-types/CMakeLists.txt
@@ -39,7 +39,6 @@ add_header(gid_t HDR gid_t.h)
add_header(uid_t HDR uid_t.h)
add_header(imaxdiv_t HDR imaxdiv_t.h)
add_header(ino_t HDR ino_t.h)
-add_header(jmp_buf HDR jmp_buf.h)
add_header(mbstate_t HDR mbstate_t.h)
add_header(mode_t HDR mode_t.h)
add_header(mtx_t HDR mtx_t.h DEPENDS .__futex_word .__mutex_type)
@@ -83,6 +82,7 @@ add_header(union_sigval HDR union_sigval.h)
add_header(siginfo_t HDR siginfo_t.h DEPENDS .union_sigval .pid_t .uid_t .clock_t)
add_header(sig_atomic_t HDR sig_atomic_t.h)
add_header(sigset_t HDR sigset_t.h DEPENDS libc.include.llvm-libc-macros.signal_macros)
+add_header(jmp_buf HDR jmp_buf.h DEPENDS .sigset_t)
add_header(struct_sigaction HDR struct_sigaction.h DEPENDS .sigset_t .siginfo_t)
add_header(struct_timespec HDR struct_timespec.h DEPENDS .time_t)
add_header(
diff --git a/libc/include/llvm-libc-types/jmp_buf.h b/libc/include/llvm-libc-types/jmp_buf.h
index f246e6491cf55..1e7791610857d 100644
--- a/libc/include/llvm-libc-types/jmp_buf.h
+++ b/libc/include/llvm-libc-types/jmp_buf.h
@@ -9,6 +9,8 @@
#ifndef LLVM_LIBC_TYPES_JMP_BUF_H
#define LLVM_LIBC_TYPES_JMP_BUF_H
+#include "sigset_t.h"
+
typedef struct {
#ifdef __x86_64__
__UINT64_TYPE__ rbx;
@@ -49,9 +51,22 @@ typedef struct {
#endif
#else
#error "__jmp_buf not available for your target architecture."
+#endif
+ // TODO: implement sigjmp_buf related functions for other architectures
+ // Issue: https://github.com/llvm/llvm-project/issues/136358
+#if defined(__i386__) || defined(__x86_64__)
+ // return address
+ void *sig_retaddr;
+ // extra register buffer to avoid indefinite stack growth in sigsetjmp
+ void *sig_extra;
+ // signal masks
+ sigset_t sigmask;
#endif
} __jmp_buf;
typedef __jmp_buf jmp_buf[1];
+#if defined(__i386__) || defined(__x86_64__)
+typedef __jmp_buf sigjmp_buf[1];
+#endif
#endif // LLVM_LIBC_TYPES_JMP_BUF_H
diff --git a/libc/include/setjmp.yaml b/libc/include/setjmp.yaml
index 5fbb9eb2a47e5..00049e58c86c8 100644
--- a/libc/include/setjmp.yaml
+++ b/libc/include/setjmp.yaml
@@ -21,3 +21,19 @@ functions:
- _Returns_twice
arguments:
- type: jmp_buf
+ - name: sigsetjmp
+ standards:
+ - POSIX
+ return_type: int
+ attributes:
+ - _Returns_twice
+ arguments:
+ - type: sigjmp_buf
+ - type: int
+ - name: siglongjmp
+ standards:
+ - POSIX
+ return_type: _Noreturn void
+ arguments:
+ - type: sigjmp_buf
+ - type: int
diff --git a/libc/src/setjmp/CMakeLists.txt b/libc/src/setjmp/CMakeLists.txt
index d85c532e8636c..2591319f15240 100644
--- a/libc/src/setjmp/CMakeLists.txt
+++ b/libc/src/setjmp/CMakeLists.txt
@@ -1,3 +1,13 @@
+if(EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/${LIBC_TARGET_OS})
+ add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/${LIBC_TARGET_OS})
+ add_object_library(
+ sigsetjmp_epilogue
+ ALIAS
+ DEPENDS
+ .${LIBC_TARGET_OS}.sigsetjmp_epilogue
+ )
+endif()
+
if(EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/${LIBC_TARGET_ARCHITECTURE})
add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/${LIBC_TARGET_ARCHITECTURE})
endif()
@@ -15,3 +25,20 @@ add_entrypoint_object(
DEPENDS
.${LIBC_TARGET_ARCHITECTURE}.longjmp
)
+
+add_entrypoint_object(
+ siglongjmp
+ SRCS
+ siglongjmp.cpp
+ HDRS
+ siglongjmp.h
+ DEPENDS
+ .longjmp
+)
+
+add_entrypoint_object(
+ sigsetjmp
+ ALIAS
+ DEPENDS
+ .${LIBC_TARGET_ARCHITECTURE}.sigsetjmp
+)
diff --git a/libc/src/setjmp/linux/CMakeLists.txt b/libc/src/setjmp/linux/CMakeLists.txt
new file mode 100644
index 0000000000000..b844c8c5ee55a
--- /dev/null
+++ b/libc/src/setjmp/linux/CMakeLists.txt
@@ -0,0 +1,12 @@
+add_object_library(
+ sigsetjmp_epilogue
+ HDRS
+ ../sigsetjmp_epilogue.h
+ SRCS
+ sigsetjmp_epilogue.cpp
+ DEPENDS
+ libc.src.__support.common
+ libc.src.__support.OSUtil.osutil
+ libc.hdr.types.jmp_buf
+ libc.hdr.types.sigset_t
+)
diff --git a/libc/src/setjmp/linux/sigsetjmp_epilogue.cpp b/libc/src/setjmp/linux/sigsetjmp_epilogue.cpp
new file mode 100644
index 0000000000000..4718623c488ec
--- /dev/null
+++ b/libc/src/setjmp/linux/sigsetjmp_epilogue.cpp
@@ -0,0 +1,25 @@
+//===-- Implementation of sigsetjmp_epilogue ------------------------------===//
+//
+// 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_epilogue.h"
+#include "src/__support/OSUtil/syscall.h"
+#include "src/__support/common.h"
+#include <sys/syscall.h> // For syscall numbers.
+
+namespace LIBC_NAMESPACE_DECL {
+[[gnu::returns_twice]] int sigsetjmp_epilogue(jmp_buf buffer, int retval) {
+ // If set is NULL, then the signal mask is unchanged (i.e., how is
+ // ignored), but the current value of the signal mask is nevertheless
+ // returned in oldset (if it is not NULL).
+ syscall_impl<long>(SYS_rt_sigprocmask, SIG_SETMASK,
+ /* set= */ retval ? &buffer->sigmask : nullptr,
+ /* old_set= */ retval ? nullptr : &buffer->sigmask,
+ sizeof(sigset_t));
+ return retval;
+}
+} // namespace LIBC_NAMESPACE_DECL
diff --git a/libc/src/setjmp/setjmp_impl.h b/libc/src/setjmp/setjmp_impl.h
index 669f720bda5d3..c89d6bc07c900 100644
--- a/libc/src/setjmp/setjmp_impl.h
+++ b/libc/src/setjmp/setjmp_impl.h
@@ -29,7 +29,8 @@ namespace LIBC_NAMESPACE_DECL {
#ifdef LIBC_COMPILER_IS_GCC
[[gnu::nothrow]]
#endif
-__attribute__((returns_twice)) int setjmp(jmp_buf buf);
+[[gnu::returns_twice]] int
+setjmp(jmp_buf buf);
} // namespace LIBC_NAMESPACE_DECL
diff --git a/libc/src/setjmp/siglongjmp.cpp b/libc/src/setjmp/siglongjmp.cpp
new file mode 100644
index 0000000000000..e372a6fa37503
--- /dev/null
+++ b/libc/src/setjmp/siglongjmp.cpp
@@ -0,0 +1,23 @@
+//===-- Implementation of siglongjmp --------------------------------------===//
+//
+// 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/siglongjmp.h"
+#include "src/__support/common.h"
+#include "src/setjmp/longjmp.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+// siglongjmp is the same as longjmp. The additional recovery work is done in
+// the epilogue of the sigsetjmp function.
+// TODO: move this inside the TU of longjmp and making it an alias after
+// sigsetjmp is implemented for all architectures.
+LLVM_LIBC_FUNCTION(void, siglongjmp, (jmp_buf buf, int val)) {
+ return LIBC_NAMESPACE::longjmp(buf, val);
+}
+
+} // namespace LIBC_NAMESPACE_DECL
diff --git a/libc/src/setjmp/siglongjmp.h b/libc/src/setjmp/siglongjmp.h
new file mode 100644
index 0000000000000..ea5bbb91df2ec
--- /dev/null
+++ b/libc/src/setjmp/siglongjmp.h
@@ -0,0 +1,25 @@
+//===-- Implementation header for siglongjmp --------------------*- C++ -*-===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_SRC_SETJMP_SIGLONGJMP_H
+#define LLVM_LIBC_SRC_SETJMP_SIGLONGJMP_H
+
+#include "hdr/types/jmp_buf.h"
+#include "src/__support/macros/config.h"
+#include "src/__support/macros/properties/compiler.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+#ifdef LIBC_COMPILER_IS_GCC
+[[gnu::nothrow]]
+#endif
+void siglongjmp(jmp_buf buf, int val);
+
+} // namespace LIBC_NAMESPACE_DECL
+
+#endif // LLVM_LIBC_SRC_SETJMP_SIGLONGJMP_H
diff --git a/libc/src/setjmp/sigsetjmp.h b/libc/src/setjmp/sigsetjmp.h
new file mode 100644
index 0000000000000..ef060c8b344a6
--- /dev/null
+++ b/libc/src/setjmp/sigsetjmp.h
@@ -0,0 +1,26 @@
+//===-- Implementation header for sigsetjmp ---------------------*- C++ -*-===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_SRC_SETJMP_SIGSETJMP_H
+#define LLVM_LIBC_SRC_SETJMP_SIGSETJMP_H
+
+#include "hdr/types/jmp_buf.h"
+#include "src/__support/macros/config.h"
+#include "src/__support/macros/properties/compiler.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+#ifdef LIBC_COMPILER_IS_GCC
+[[gnu::nothrow]]
+#endif
+[[gnu::returns_twice]] int
+sigsetjmp(sigjmp_buf buf, int savesigs);
+
+} // namespace LIBC_NAMESPACE_DECL
+
+#endif // LLVM_LIBC_SRC_SETJMP_SIGSETJMP_H
diff --git a/libc/src/setjmp/sigsetjmp_epilogue.h b/libc/src/setjmp/sigsetjmp_epilogue.h
new file mode 100644
index 0000000000000..88702b743940f
--- /dev/null
+++ b/libc/src/setjmp/sigsetjmp_epilogue.h
@@ -0,0 +1,19 @@
+//===-- Implementation header for sigsetjmp epilogue ------------*- C++ -*-===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_SRC_SETJMP_SIGSETJMP_EPILOGUE_H
+#define LLVM_LIBC_SRC_SETJMP_SIGSETJMP_EPILOGUE_H
+
+#include "hdr/types/jmp_buf.h"
+#include "src/__support/common.h"
+
+namespace LIBC_NAMESPACE_DECL {
+[[gnu::returns_twice]] int sigsetjmp_epilogue(jmp_buf buffer, int retval);
+} // namespace LIBC_NAMESPACE_DECL
+
+#endif // LLVM_LIBC_SRC_SETJMP_SIGSETJMP_EPILOGUE_H
diff --git a/libc/src/setjmp/x86_64/CMakeLists.txt b/libc/src/setjmp/x86_64/CMakeLists.txt
index 96d5751bc81dd..0090e81655662 100644
--- a/libc/src/setjmp/x86_64/CMakeLists.txt
+++ b/libc/src/setjmp/x86_64/CMakeLists.txt
@@ -5,9 +5,22 @@ add_entrypoint_object(
HDRS
../setjmp_impl.h
DEPENDS
+ libc.hdr.offsetof_macros
libc.hdr.types.jmp_buf
- COMPILE_OPTIONS
- ${libc_opt_high_flag}
+)
+
+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
)
add_entrypoint_object(
@@ -18,7 +31,4 @@ add_entrypoint_object(
../longjmp.h
DEPENDS
libc.hdr.types.jmp_buf
- COMPILE_OPTIONS
- ${libc_opt_high_flag}
- -fomit-frame-pointer
)
diff --git a/libc/src/setjmp/x86_64/setjmp.cpp b/libc/src/setjmp/x86_64/setjmp.cpp
index 5ac10fa87b39a..28e52712c785d 100644
--- a/libc/src/setjmp/x86_64/setjmp.cpp
+++ b/libc/src/setjmp/x86_64/setjmp.cpp
@@ -6,7 +6,7 @@
//
//===----------------------------------------------------------------------===//
-#include "include/llvm-libc-macros/offsetof-macro.h"
+#include "hdr/offsetof_macros.h"
#include "src/__support/common.h"
#include "src/__support/macros/config.h"
#include "src/setjmp/setjmp_impl.h"
diff --git a/libc/src/setjmp/x86_64/sigsetjmp.cpp b/libc/src/setjmp/x86_64/sigsetjmp.cpp
new file mode 100644
index 0000000000000..4c97a01822679
--- /dev/null
+++ b/libc/src/setjmp/x86_64/sigsetjmp.cpp
@@ -0,0 +1,68 @@
+//===-- 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"
+
+#if !defined(LIBC_TARGET_ARCH_IS_X86)
+#error "Invalid file include"
+#endif
+namespace LIBC_NAMESPACE_DECL {
+#ifdef __i386__
+[[gnu::naked]]
+LLVM_LIBC_FUNCTION(int, sigsetjmp, (sigjmp_buf buf)) {
+ asm(R"(
+ mov 8(%%esp), %%ecx
+ jecxz .Lnosave
+
+ mov 4(%%esp), %%eax
+ pop %c[retaddr](%%eax)
+ mov %%ebx, %c[extra](%%eax)
+ mov %%eax, %%ebx
+ call %P[setjmp]
+ push %c[retaddr](%%ebx)
+ mov %%ebx,4(%%esp)
+ mov %%eax,8(%%esp)
+ mov %c[extra](%%ebx), %%ebx
+ jmp %P[epilogue]
+
+.Lnosave:
+ jmp %P[setjmp])" ::[retaddr] "i"(offsetof(__jmp_buf, sig_retaddr)),
+ [extra] "i"(offsetof(__jmp_buf, sig_extra)), [setjmp] "X"(setjmp),
+ [epilogue] "X"(sigsetjmp_epilogue)
+ : "eax", "ebx", "ecx");
+}
+#endif
+[[gnu::naked]]
+LLVM_LIBC_FUNCTION(int, sigsetjmp, (sigjmp_buf, int)) {
+ asm(R"(
+ test %%esi, %%esi
+ jz .Lnosave
+
+ pop %c[retaddr](%%rdi)
+ mov %%rbx, %c[extra](%%rdi)
+ mov %%rdi, %%rbx
+ call %P[setjmp]
+ push %c[retaddr](%%rbx)
+ mov %%rbx, %%rdi
+ mov %%eax, %%esi
+ mov %c[extra](%%rdi), %%rbx
+ jmp %P[epilogue]
+
+.Lnosave:
+ jmp %P[setjmp])" ::[retaddr] "i"(offsetof(__jmp_buf, sig_retaddr)),
+ [extra] "i"(offsetof(__jmp_buf, sig_extra)), [setjmp] "X"(setjmp),
+ [epilogue] "X"(sigsetjmp_epilogue)
+ : "rax", "rbx");
+}
+
+} // namespace LIBC_NAMESPACE_DECL
diff --git a/libc/test/src/setjmp/CMakeLists.txt b/libc/test/src/setjmp/CMakeLists.txt
index 392230784bd99..e95476e00e54b 100644
--- a/libc/test/src/setjmp/CMakeLists.txt
+++ b/libc/test/src/setjmp/CMakeLists.txt
@@ -17,3 +17,20 @@ add_libc_unittest(
libc.src.setjmp.longjmp
libc.src.setjmp.setjmp
)
+
+add_libc_unittest(
+ sigsetjmp_test
+ SUITE
+ libc_setjmp_unittests
+ SRCS
+ sigsetjmp_test.cpp
+ CXX_STANDARD
+ 20
+ DEPENDS
+ libc.src.setjmp.sigsetjmp
+ libc.src.setjmp.siglongjmp
+ libc.src.signal.sigprocmask
+ libc.src.string.memset
+ libc.src.string.memcmp
+ libc.hdr.types.sigset_t
+)
diff --git a/libc/test/src/setjmp/sigsetjmp_test.cpp b/libc/test/src/setjmp/sigsetjmp_test.cpp
new file mode 100644
index 0000000000000..cf8d2f2fab347
--- /dev/null
+++ b/libc/test/src/setjmp/sigsetjmp_test.cpp
@@ -0,0 +1,88 @@
+//===-- Unittests for sigsetjmp and siglongjmp ----------------------------===//
+//
+// 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/siglongjmp.h"
+#include "src/setjmp/sigsetjmp.h"
+#include "src/signal/sigprocmask.h"
+#include "src/string/memcmp.h"
+#include "src/string/memset.h"
+#include "test/UnitTest/Test.h"
+
+constexpr int MAX_LOOP = 123;
+int longjmp_called = 0;
+
+void jump_back(jmp_buf buf, int n) {
+ longjmp_called++;
+ LIBC_NAMESPACE::siglongjmp(buf, n); // Will return |n| out of setjmp
+}
+
+TEST(LlvmLibcSetJmpTest, SigSetAndJumpBackSaveSigs) {
+ jmp_buf buf;
+ longjmp_called = 0;
+ volatile int n = 0;
+ sigset_t old;
+ sigset_t mask_all;
+ sigset_t recovered;
+ LIBC_NAMESPACE::memset(&mask_all, 0xFF, sizeof(mask_all));
+ LIBC_NAMESPACE::memset(&old, 0, sizeof(old));
+ LIBC_NAMESPACE::memset(&recovered, 0, sizeof(recovered));
+ LIBC_NAMESPACE::sigprocmask(0, nullptr, &old);
+ if (LIBC_NAMESPACE::sigsetjmp(buf, 1) <= MAX_LOOP) {
+ LIBC_NAMESPACE::sigprocmask(0, nullptr, &recovered);
+ ASSERT_EQ(0, LIBC_NAMESPACE::memcmp(&old, &recovered, sizeof(old)));
+ n = n + 1;
+ LIBC_NAMESPACE::sigprocmask(SIG_BLOCK, &mask_all, nullptr);
+ jump_back(buf, n);
+ }
+ ASSERT_EQ(longjmp_called, n);
+ ASSERT_EQ(n, MAX_LOOP + 1);
+}
+
+TEST(LlvmLibcSetJmpTest, SigSetAndJumpBackValOneSaveSigs) {
+ jmp_buf buf;
+ longjmp_called = 0;
+ sigset_t old;
+ sigset_t mask_all;
+ sigset_t recovered;
+ LIBC_NAMESPACE::memset(&mask_all, 0xFF, sizeof(mask_all));
+ LIBC_NAMESPACE::memset(&old, 0, sizeof(old));
+ LIBC_NAMESPACE::memset(&recovered, 0, sizeof(recovered));
+ LIBC_NAMESPACE::sigprocmask(0, nullptr, &old);
+ int val = LIBC_NAMESPACE::sigsetjmp(buf, 1);
+ if (val == 0) {
+ LIBC_NAMESPACE::sigprocmask(SIG_BLOCK, &mask_all, nullptr);
+ jump_back(buf, val);
+ }
+ LIBC_NAMESPACE::sigprocmask(0, nullptr, &recovered);
+ ASSERT_EQ(0, LIBC_NAMESPACE::memcmp(&old, &recovered, sizeof(old)));
+ ASSERT_EQ(longjmp_called, 1);
+ ASSERT_EQ(val, 1);
+}
+
+TEST(LlvmLibcSetJmpTest, SigSetAndJumpBackNoSaveSigs) {
+ jmp_buf buf;
+ longjmp_called = 0;
+ volatile int n = 0;
+ if (LIBC_NAMESPACE::sigsetjmp(buf, 0) <= MAX_LOOP) {
+ n = n + 1;
+ jump_back(buf, n);
+ }
+ ASSERT_EQ(longjmp_called, n);
+ ASSERT_EQ(n, MAX_LOOP + 1);
+}
+
+TEST(LlvmLibcSetJmpTest, SigSetAndJumpBackValOneNoSaveSigs) {
+ jmp_buf buf;
+ longjmp_called = 0;
+ int val = LIBC_NAMESPACE::sigsetjmp(buf, 0);
+ if (val == 0) {
+ jump_back(buf, val);
+ }
+ ASSERT_EQ(longjmp_called, 1);
+ ASSERT_EQ(val, 1);
+}
>From 230422621aeb97c4839ba133c75c33496aa5a75a Mon Sep 17 00:00:00 2001
From: Schrodinger ZHU Yifan <yifanzhu at rochester.edu>
Date: Thu, 24 Apr 2025 13:15:42 -0400
Subject: [PATCH 2/5] fix build again
---
libc/src/setjmp/CMakeLists.txt | 32 ++++++++++++++-------------
libc/src/setjmp/x86_64/CMakeLists.txt | 29 ++++++++++++------------
2 files changed, 32 insertions(+), 29 deletions(-)
diff --git a/libc/src/setjmp/CMakeLists.txt b/libc/src/setjmp/CMakeLists.txt
index 2591319f15240..239254fa57dc6 100644
--- a/libc/src/setjmp/CMakeLists.txt
+++ b/libc/src/setjmp/CMakeLists.txt
@@ -26,19 +26,21 @@ add_entrypoint_object(
.${LIBC_TARGET_ARCHITECTURE}.longjmp
)
-add_entrypoint_object(
- siglongjmp
- SRCS
- siglongjmp.cpp
- HDRS
- siglongjmp.h
- DEPENDS
- .longjmp
-)
+if (TARGET libc.src.setjmp.sigsetjmp_epilogue)
+ add_entrypoint_object(
+ siglongjmp
+ SRCS
+ siglongjmp.cpp
+ HDRS
+ siglongjmp.h
+ DEPENDS
+ .longjmp
+ )
-add_entrypoint_object(
- sigsetjmp
- ALIAS
- DEPENDS
- .${LIBC_TARGET_ARCHITECTURE}.sigsetjmp
-)
+ add_entrypoint_object(
+ sigsetjmp
+ ALIAS
+ DEPENDS
+ .${LIBC_TARGET_ARCHITECTURE}.sigsetjmp
+ )
+endif()
diff --git a/libc/src/setjmp/x86_64/CMakeLists.txt b/libc/src/setjmp/x86_64/CMakeLists.txt
index 0090e81655662..03ed5fb647084 100644
--- a/libc/src/setjmp/x86_64/CMakeLists.txt
+++ b/libc/src/setjmp/x86_64/CMakeLists.txt
@@ -8,20 +8,21 @@ add_entrypoint_object(
libc.hdr.offsetof_macros
libc.hdr.types.jmp_buf
)
-
-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
-)
+if (TARGET libc.src.setjmp.sigsetjmp_epilogue)
+ 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
+ )
+endif()
add_entrypoint_object(
longjmp
>From 3591028462d189befbe038e7a87bd9a08da7b26e Mon Sep 17 00:00:00 2001
From: Schrodinger ZHU Yifan <i at zhuyi.fan>
Date: Thu, 24 Apr 2025 16:21:47 -0400
Subject: [PATCH 3/5] [libc] more amendments
---
libc/include/llvm-libc-types/jmp_buf.h | 2 ++
1 file changed, 2 insertions(+)
diff --git a/libc/include/llvm-libc-types/jmp_buf.h b/libc/include/llvm-libc-types/jmp_buf.h
index 1e7791610857d..a6638b222138a 100644
--- a/libc/include/llvm-libc-types/jmp_buf.h
+++ b/libc/include/llvm-libc-types/jmp_buf.h
@@ -9,7 +9,9 @@
#ifndef LLVM_LIBC_TYPES_JMP_BUF_H
#define LLVM_LIBC_TYPES_JMP_BUF_H
+#if defined(__i386__) || defined(__x86_64__)
#include "sigset_t.h"
+#endif
typedef struct {
#ifdef __x86_64__
>From 8ce5c04559d3c66700fa8e62bcc47a6b02c29535 Mon Sep 17 00:00:00 2001
From: Schrodinger ZHU Yifan <yifanzhu at rochester.edu>
Date: Thu, 24 Apr 2025 19:32:58 -0400
Subject: [PATCH 4/5] update jmp_buf.h to always gate this by __linux__
---
libc/include/llvm-libc-types/jmp_buf.h | 17 ++++++++++++-----
1 file changed, 12 insertions(+), 5 deletions(-)
diff --git a/libc/include/llvm-libc-types/jmp_buf.h b/libc/include/llvm-libc-types/jmp_buf.h
index a6638b222138a..90bd60d741293 100644
--- a/libc/include/llvm-libc-types/jmp_buf.h
+++ b/libc/include/llvm-libc-types/jmp_buf.h
@@ -9,7 +9,13 @@
#ifndef LLVM_LIBC_TYPES_JMP_BUF_H
#define LLVM_LIBC_TYPES_JMP_BUF_H
-#if defined(__i386__) || defined(__x86_64__)
+// TODO: implement sigjmp_buf related functions for other architectures
+// Issue: https://github.com/llvm/llvm-project/issues/136358
+#if defined(__linux__) && (defined(__i386__) || defined(__x86_64__))
+#define __LIBC_HAS_SIGJMP_BUF
+#endif
+
+#if defined(__LIBC_HAS_SIGJMP_BUF)
#include "sigset_t.h"
#endif
@@ -54,9 +60,7 @@ typedef struct {
#else
#error "__jmp_buf not available for your target architecture."
#endif
- // TODO: implement sigjmp_buf related functions for other architectures
- // Issue: https://github.com/llvm/llvm-project/issues/136358
-#if defined(__i386__) || defined(__x86_64__)
+#if defined(__LIBC_HAS_SIGJMP_BUF)
// return address
void *sig_retaddr;
// extra register buffer to avoid indefinite stack growth in sigsetjmp
@@ -68,7 +72,10 @@ typedef struct {
typedef __jmp_buf jmp_buf[1];
-#if defined(__i386__) || defined(__x86_64__)
+#if defined(__LIBC_HAS_SIGJMP_BUF)
typedef __jmp_buf sigjmp_buf[1];
#endif
+
+#undef __LIBC_HAS_SIGJMP_BUF
+
#endif // LLVM_LIBC_TYPES_JMP_BUF_H
>From 277eb688831bf203f32602ca783af044874c5470 Mon Sep 17 00:00:00 2001
From: Schrodinger ZHU Yifan <yifanzhu at rochester.edu>
Date: Tue, 29 Apr 2025 08:55:01 -0400
Subject: [PATCH 5/5] Update libc/include/llvm-libc-types/jmp_buf.h
Co-authored-by: Petr Hosek <phosek at google.com>
---
libc/include/llvm-libc-types/jmp_buf.h | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/libc/include/llvm-libc-types/jmp_buf.h b/libc/include/llvm-libc-types/jmp_buf.h
index 90bd60d741293..d1a13a353d17c 100644
--- a/libc/include/llvm-libc-types/jmp_buf.h
+++ b/libc/include/llvm-libc-types/jmp_buf.h
@@ -11,9 +11,11 @@
// TODO: implement sigjmp_buf related functions for other architectures
// Issue: https://github.com/llvm/llvm-project/issues/136358
-#if defined(__linux__) && (defined(__i386__) || defined(__x86_64__))
+#if defined(__linux__)
+#if defined(__i386__) || defined(__x86_64__)
#define __LIBC_HAS_SIGJMP_BUF
#endif
+#endif
#if defined(__LIBC_HAS_SIGJMP_BUF)
#include "sigset_t.h"
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