Add support for LLVM profile for NetBSD

[krytarowski]

Summary

NetBSD uses typical UNIX interfaces.

All tests pass except instrprof-dlopen-dlclose-gcov.test, as there
is not supported semantics of atexit(3) in dlopen(3)ed+dlclose(3)d
DSO.

NetBSD also ships an older version of LLVM profile (ABI v.2 predating
ABI v.4 in upstream version) inside libc. That copy has been manually
removed during the porting and testing process of the upstream version
to NetBSD. Otherwise there were conflicts between them two.

[krytarowski]

@joerg I was trying to change atexit(3) calls to C++ destructors or GCC destructiors (__attribute__((destructor))), but none of that worked.

For the former:

/public/llvm-build/lib/clang/8.0.0/lib/netbsd/libclang_rt.profile-x86_64.a(InstrProfilingRuntime.cc.o): In function `__clang_call_terminate':
InstrProfilingRuntime.cc:(.text.__clang_call_terminate[__clang_call_terminate]+0x2): undefined reference to `__cxa_begin_catch'
InstrProfilingRuntime.cc:(.text.__clang_call_terminate[__clang_call_terminate]+0x7): undefined reference to `std::terminate()'
/public/llvm-build/lib/clang/8.0.0/lib/netbsd/libclang_rt.profile-x86_64.a(InstrProfilingRuntime.cc.o):(.data.DW.ref.__gxx_personality_v0[DW.ref.__gxx_personality_v0]+0x0): undefined reference to `__gxx_personality_v0'
clang-8: error: linker command failed with exit code 1 (use -v to see invocation)

For the latter hangs and crashes of many/all tests.

[vsk]

Thanks, this patch lgtm.

In D55997#1338996, @krytarowski wrote:

@joerg I was trying to change atexit(3) calls to C++ destructors or GCC destructiors (__attribute__((destructor))), but none of that worked.

For the former:

/public/llvm-build/lib/clang/8.0.0/lib/netbsd/libclang_rt.profile-x86_64.a(InstrProfilingRuntime.cc.o): In function `__clang_call_terminate':
InstrProfilingRuntime.cc:(.text.__clang_call_terminate[__clang_call_terminate]+0x2): undefined reference to `__cxa_begin_catch'
InstrProfilingRuntime.cc:(.text.__clang_call_terminate[__clang_call_terminate]+0x7): undefined reference to `std::terminate()'
/public/llvm-build/lib/clang/8.0.0/lib/netbsd/libclang_rt.profile-x86_64.a(InstrProfilingRuntime.cc.o):(.data.DW.ref.__gxx_personality_v0[DW.ref.__gxx_personality_v0]+0x0): undefined reference to `__gxx_personality_v0'
clang-8: error: linker command failed with exit code 1 (use -v to see invocation)

For the latter hangs and crashes of many/all tests.

Looks like you're missing the C++ runtime (libcxxabi or libcxx, IIRC, although you may be using libstdc++)?

[krytarowski]

In D55997#1340069, @vsk wrote:

Thanks, this patch lgtm.

In D55997#1338996, @krytarowski wrote:

@joerg I was trying to change atexit(3) calls to C++ destructors or GCC destructiors (__attribute__((destructor))), but none of that worked.

For the former:

/public/llvm-build/lib/clang/8.0.0/lib/netbsd/libclang_rt.profile-x86_64.a(InstrProfilingRuntime.cc.o): In function `__clang_call_terminate':
InstrProfilingRuntime.cc:(.text.__clang_call_terminate[__clang_call_terminate]+0x2): undefined reference to `__cxa_begin_catch'
InstrProfilingRuntime.cc:(.text.__clang_call_terminate[__clang_call_terminate]+0x7): undefined reference to `std::terminate()'
/public/llvm-build/lib/clang/8.0.0/lib/netbsd/libclang_rt.profile-x86_64.a(InstrProfilingRuntime.cc.o):(.data.DW.ref.__gxx_personality_v0[DW.ref.__gxx_personality_v0]+0x0): undefined reference to `__gxx_personality_v0'
clang-8: error: linker command failed with exit code 1 (use -v to see invocation)

For the latter hangs and crashes of many/all tests.

Looks like you're missing the C++ runtime (libcxxabi or libcxx, IIRC, although you may be using libstdc++)?

I will defer for now this to @joerg to find an atexit(3) replacement to fix instrprof-dlopen-dlclose-gcov.test.

cmake/config-ix.cmake

 if (COMPILER_RT_HAS_SANITIZER_COMMON AND HWASAN_SUPPORTED_ARCH AND
     OS_NAME MATCHES "Linux|Android")
   set(COMPILER_RT_HAS_HWASAN TRUE)
 else()
   set(COMPILER_RT_HAS_HWASAN FALSE)
 endif()
 
 if (PROFILE_SUPPORTED_ARCH AND NOT LLVM_USE_SANITIZER AND
-    OS_NAME MATCHES "Darwin|Linux|FreeBSD|Windows|Android|Fuchsia|SunOS")
+    OS_NAME MATCHES "Darwin|Linux|FreeBSD|Windows|Android|Fuchsia|SunOS|NetBSD")
   set(COMPILER_RT_HAS_PROFILE TRUE)
 else()
   set(COMPILER_RT_HAS_PROFILE FALSE)
 endif()
 
 if (COMPILER_RT_HAS_SANITIZER_COMMON AND TSAN_SUPPORTED_ARCH AND
     OS_NAME MATCHES "Darwin|Linux|FreeBSD|Android|NetBSD")
   set(COMPILER_RT_HAS_TSAN TRUE)

lib/profile/InstrProfilingPlatformLinux.c

 /*===- InstrProfilingPlatformLinux.c - Profile data Linux platform ------===*\
 |*
 |*                     The LLVM Compiler Infrastructure
 |*
 |* This file is distributed under the University of Illinois Open Source
 |* License. See LICENSE.TXT for details.
 |*
 \*===----------------------------------------------------------------------===*/
 
 #if defined(__linux__) || defined(__FreeBSD__) || defined(__Fuchsia__) || \
-    (defined(__sun__) && defined(__svr4__))
+    (defined(__sun__) && defined(__svr4__)) || defined(__NetBSD__)
 
 #include <stdlib.h>
 
 #include "InstrProfiling.h"
 
 #define PROF_DATA_START INSTR_PROF_SECT_START(INSTR_PROF_DATA_SECT_NAME)
 #define PROF_DATA_STOP INSTR_PROF_SECT_STOP(INSTR_PROF_DATA_SECT_NAME)
 #define PROF_NAME_START INSTR_PROF_SECT_START(INSTR_PROF_NAME_SECT_NAME)

lib/profile/InstrProfilingPlatformOther.c

 /*===- InstrProfilingPlatformOther.c - Profile data default platform ------===*\
 |*
 |*                     The LLVM Compiler Infrastructure
 |*
 |* This file is distributed under the University of Illinois Open Source
 |* License. See LICENSE.TXT for details.
 |*
 \*===----------------------------------------------------------------------===*/
 
 #if !defined(__APPLE__) && !defined(__linux__) && !defined(__FreeBSD__) && \
-    !(defined(__sun__) && defined(__svr4__))
+    !(defined(__sun__) && defined(__svr4__)) && !defined(__NetBSD__)
 
 #include <stdlib.h>
 
 #include "InstrProfiling.h"
 
 static const __llvm_profile_data *DataFirst = NULL;
 static const __llvm_profile_data *DataLast = NULL;
 static const char *NamesFirst = NULL;

test/profile/instrprof-dlopen-dlclose-gcov.test

+# atexit(3) not supported in dlopen(3)ed+dlclose(3)d DSO
+XFAIL: netbsd
+
 RUN: mkdir -p %t.d
 RUN: cd %t.d
 
 RUN: %clang --coverage -o func.shared -fPIC -shared %S/Inputs/instrprof-dlopen-func.c
 RUN: %clang --coverage -o func2.shared -fPIC -shared %S/Inputs/instrprof-dlopen-func2.c
 RUN: %clang --coverage -o func3.shared -fPIC -shared %S/Inputs/instrprof-dlopen-func3.c
 RUN: %clang --coverage -o %t -fPIC -rpath %t.d %S/Inputs/instrprof-dlopen-dlclose-main.c
 

test/profile/lit.cfg

 config.substitutions.append( ("%clang_profgen_gcc=", build_invocation(clang_cflags) + " -fprofile-generate=") )
 config.substitutions.append( ("%clang_profuse_gcc=", build_invocation(clang_cflags) + " -fprofile-use=") )
 
 config.substitutions.append( ("%clang_profuse=", build_invocation(clang_cflags) + " -fprofile-instr-use=") )
 config.substitutions.append( ("%clangxx_profuse=", build_invocation(clang_cxxflags) + " -fprofile-instr-use=") )
 
 config.substitutions.append( ("%clang_lto_profgen=", build_invocation(clang_cflags, True) + " -fprofile-instr-generate=") )
 
-if config.host_os not in ['Darwin', 'FreeBSD', 'Linux', 'SunOS']:
+if config.host_os not in ['Darwin', 'FreeBSD', 'Linux', 'NetBSD', 'SunOS']:
   config.unsupported = True
 
 if config.target_arch in ['armv7l']:
   config.unsupported = True
 
 if config.android:
   config.unsupported = True