[llvm] ae032e2 - [CMake][ExecutionEngine] add HAVE_(DE)REGISTER_FRAME as a config.h macros

[David Tenty via llvm-commits]

Author: David Tenty
Date: 2020-11-10T13:09:44-05:00
New Revision: ae032e2714675354457c474f4c8f5581714e33d1

URL: https://github.com/llvm/llvm-project/commit/ae032e2714675354457c474f4c8f5581714e33d1
DIFF: https://github.com/llvm/llvm-project/commit/ae032e2714675354457c474f4c8f5581714e33d1.diff

LOG: [CMake][ExecutionEngine] add HAVE_(DE)REGISTER_FRAME  as a config.h macros

The macro HAVE_EHTABLE_SUPPORT is used by parts of ExecutionEngine to tell __register_frame/__deregister_frame is available to register the
FDE for a generated (JIT) code. It's currently set by a slowly growing set of macro tests in the respective headers, which is updated now and then when it fails to link on some platform or another due to the symbols being missing (see for example https://bugs.llvm.org/show_bug.cgi?id=5715).

This change converts the macro in two HAVE_(DE)REGISTER_FRAME config.h macros (like most of the other HAVE_* macros) and set's them based on whether CMake can actually find a definition for these symbols to link to at configuration time.

Reviewed By: hubert.reinterpretcast

Differential Revision: https://reviews.llvm.org/D87114

Added: 
    llvm/cmake/unwind.h

Modified: 
    llvm/cmake/config-ix.cmake
    llvm/include/llvm/Config/config.h.cmake
    llvm/lib/ExecutionEngine/JITLink/EHFrameSupport.cpp
    llvm/lib/ExecutionEngine/RuntimeDyld/RTDyldMemoryManager.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/cmake/config-ix.cmake b/llvm/cmake/config-ix.cmake
index 797485e3d024..818fafbce148 100644
--- a/llvm/cmake/config-ix.cmake
+++ b/llvm/cmake/config-ix.cmake
@@ -207,6 +207,10 @@ if(C_SUPPORTS_WERROR_UNGUARDED_AVAILABILITY_NEW)
   set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -Werror=unguarded-availability-new")
 endif()
 
+# Determine whether we can register EH tables.
+check_symbol_exists(__register_frame "${CMAKE_CURRENT_LIST_DIR}/unwind.h" HAVE_REGISTER_FRAME)
+check_symbol_exists(__deregister_frame "${CMAKE_CURRENT_LIST_DIR}/unwind.h" HAVE_DEREGISTER_FRAME)
+
 check_symbol_exists(_Unwind_Backtrace "unwind.h" HAVE__UNWIND_BACKTRACE)
 check_symbol_exists(getpagesize unistd.h HAVE_GETPAGESIZE)
 check_symbol_exists(sysconf unistd.h HAVE_SYSCONF)

diff  --git a/llvm/cmake/unwind.h b/llvm/cmake/unwind.h
new file mode 100644
index 000000000000..e7f53465f9ce
--- /dev/null
+++ b/llvm/cmake/unwind.h
@@ -0,0 +1,7 @@
+// NOLINT: llvm-header-guard
+// __register_frame() is used with dynamically generated code to register the
+// FDE for a generated (JIT) code. This header provides protypes, since the gcc
+// version of unwind.h may not, so CMake can check if the corresponding symbols
+// exist in the runtime.
+extern void __register_frame(const void *fde);   // NOLINT
+extern void __deregister_frame(const void *fde); // NOLINT

diff  --git a/llvm/include/llvm/Config/config.h.cmake b/llvm/include/llvm/Config/config.h.cmake
index fc3f94570e98..6664ad335584 100644
--- a/llvm/include/llvm/Config/config.h.cmake
+++ b/llvm/include/llvm/Config/config.h.cmake
@@ -58,6 +58,12 @@
 /* Define if dladdr() is available on this platform. */
 #cmakedefine HAVE_DLADDR ${HAVE_DLADDR}
 
+/* Define to 1 if we can register EH frames on this platform. */
+#cmakedefine HAVE_REGISTER_FRAME ${HAVE_REGISTER_FRAME}
+
+/* Define to 1 if we can deregister EH frames on this platform. */
+#cmakedefine HAVE_DEREGISTER_FRAME ${HAVE_DEREGISTER_FRAME}
+
 /* Define to 1 if you have the <errno.h> header file. */
 #cmakedefine HAVE_ERRNO_H ${HAVE_ERRNO_H}
 

diff  --git a/llvm/lib/ExecutionEngine/JITLink/EHFrameSupport.cpp b/llvm/lib/ExecutionEngine/JITLink/EHFrameSupport.cpp
index 9eda6fb9ea77..b94a2b36b5f1 100644
--- a/llvm/lib/ExecutionEngine/JITLink/EHFrameSupport.cpp
+++ b/llvm/lib/ExecutionEngine/JITLink/EHFrameSupport.cpp
@@ -10,6 +10,7 @@
 #include "EHFrameSupportImpl.h"
 
 #include "llvm/BinaryFormat/Dwarf.h"
+#include "llvm/Config/config.h"
 #include "llvm/Support/DynamicLibrary.h"
 
 #define DEBUG_TYPE "jitlink"
@@ -629,16 +630,8 @@ Expected<Symbol &> EHFrameEdgeFixer::getOrCreateSymbol(ParseContext &PC,
   return PC.G.addAnonymousSymbol(*B, Addr - B->getAddress(), 0, false, false);
 }
 
-// Determine whether we can register EH tables.
-#if (defined(__GNUC__) && !defined(__ARM_EABI__) && !defined(__ia64__) &&      \
-     !(defined(_AIX) && defined(__ibmxl__)) && !defined(__MVS__) &&            \
-     !defined(__SEH__) && !defined(__USING_SJLJ_EXCEPTIONS__))
-#define HAVE_EHTABLE_SUPPORT 1
-#else
-#define HAVE_EHTABLE_SUPPORT 0
-#endif
-
-#if HAVE_EHTABLE_SUPPORT
+#if defined(HAVE_REGISTER_FRAME) && defined(HAVE_DEREGISTER_FRAME) &&          \
+    !defined(__SEH__) && !defined(__USING_SJLJ_EXCEPTIONS__)
 extern "C" void __register_frame(const void *);
 extern "C" void __deregister_frame(const void *);
 

diff  --git a/llvm/lib/ExecutionEngine/RuntimeDyld/RTDyldMemoryManager.cpp b/llvm/lib/ExecutionEngine/RuntimeDyld/RTDyldMemoryManager.cpp
index 6aa8f1cc6861..b6ccd02405c1 100644
--- a/llvm/lib/ExecutionEngine/RuntimeDyld/RTDyldMemoryManager.cpp
+++ b/llvm/lib/ExecutionEngine/RuntimeDyld/RTDyldMemoryManager.cpp
@@ -31,16 +31,8 @@ namespace llvm {
 
 RTDyldMemoryManager::~RTDyldMemoryManager() {}
 
-// Determine whether we can register EH tables.
-#if (defined(__GNUC__) && !defined(__ARM_EABI__) && !defined(__ia64__) &&      \
-     !(defined(_AIX) && defined(__ibmxl__)) && !defined(__MVS__) &&            \
-     !defined(__SEH__) && !defined(__USING_SJLJ_EXCEPTIONS__))
-#define HAVE_EHTABLE_SUPPORT 1
-#else
-#define HAVE_EHTABLE_SUPPORT 0
-#endif
-
-#if HAVE_EHTABLE_SUPPORT
+#if defined(HAVE_REGISTER_FRAME) && defined(HAVE_DEREGISTER_FRAME) &&          \
+    !defined(__SEH__) && !defined(__USING_SJLJ_EXCEPTIONS__)
 extern "C" void __register_frame(void *);
 extern "C" void __deregister_frame(void *);
 #else