Fix AddressSanitizer on s390 (31-bit)

Summary:
GET_CALLER_PC doesn't work properly on 31-bit s390, as pointers are 31-bit, the MSB bit can be set when the return address is copied into integer.
This causes e.g. errors like:
    #0 0xfdadb129  (<unknown module>)
    #1 0x7da5e1d1 in __asan::GetStackTraceWithPcBpAndContext(__sanitizer::BufferedStackTrace*, unsigned long, unsigned long, unsigned long, void*, bool) ../../../../../libsanitizer/asan/asan_stack.h:50
    #2 0x7da5e1d1 in __asan::ErrorGeneric::Print() ../../../../../libsanitizer/asan/asan_errors.cc:482
    #3 0x7db178d5 in __asan::ErrorDescription::Print() ../../../../../libsanitizer/asan/asan_errors.h:360
    #4 0x7db178d5 in __asan::ScopedInErrorReport::~ScopedInErrorReport() ../../../../../libsanitizer/asan/asan_report.cc:167
    #5 0x7db178d5 in __asan::ReportGenericError(unsigned long, unsigned long, unsigned long, unsigned long, bool, unsigned long, unsigned int, bool) ../../../../../libsanitizer/asan/asan_report.cc:397
    #6 0x7dadb14f in __interceptor_memcmp ../../../../../libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:626
    #7 0x400cf5 in main /home/jakub/gcc/gcc/testsuite/c-c++-common/asan/memcmp-1.c:14
    #8 0x7d807215 in __libc_start_main (/lib/libc.so.6+0x1a215)
    #9 0x4007ed  (/home/jakub/gcc/obj/gcc/testsuite/memcmp-1.exe+0x4007ed)

The actual return PC inside __interceptor_memcmp was 0x7dadb129 rather than 0xfdadb129.

Reviewers: koriakin, kcc

Reviewed By: kcc

Subscribers: kubamracek

Differential Revision: https://reviews.llvm.org/D29824

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@294793 91177308-0d34-0410-b5e6-96231b3b80d8

Author: kcc

lib/sanitizer_common/sanitizer_internal_defs.h

@@ -327,7 +327,12 @@ void NORETURN CheckFailed(const char *file, int line, const char *cond,
 enum LinkerInitialized { LINKER_INITIALIZED = 0 };
 
 #if !defined(_MSC_VER) || defined(__clang__)
+#if SANITIZER_S390_31
+#define GET_CALLER_PC() \
+  (__sanitizer::uptr) __builtin_extract_return_addr(__builtin_return_address(0))
+#else
 #define GET_CALLER_PC() (__sanitizer::uptr) __builtin_return_address(0)
+#endif
 #define GET_CURRENT_FRAME() (__sanitizer::uptr) __builtin_frame_address(0)
 inline void Trap() {
   __builtin_trap();