[profile][test] Fix Profile-* :: instrprof-merge.c etc. on SPARC

[ro]

Summary

While working on https://reviews.llvm.org/D40900 (which effectively is about enabling compiler-rt on sparc these days), I came across two failing profile testcases:

Profile-sparc :: instrprof-merge-match.test
Profile-sparc :: instrprof-merge.c
Profile-sparcv9 :: instrprof-merge-match.test
Profile-sparcv9 :: instrprof-merge.c

All of them crashed with a SIGBUS in __llvm_profile_merge_from_buffer:

Thread 2 received signal SIGSEGV, Segmentation fault.
[Switching to Thread 1 (LWP 1)]
0x00012368 in __llvm_profile_merge_from_buffer (
    ProfileData=0x2384c <main.Buffer> "\377lprofR\201", ProfileSize=360)
    at /vol/llvm/src/llvm/local/projects/compiler-rt/lib/profile/InstrProfilingMerge.c:95
95        SrcDataEnd = SrcDataStart + Header->DataSize;

where Header is insufficiently aligned for a strict-alignment target like SPARC.

Fixed by forcing the alignment to uint64_t, the members of struct __llvm_profile_header,
in the callers.

Tested on sparcv9-sun-solaris2.11. Ok for trunk?

[vsk]

This might need to be '__declspec(align(x))' for msvc. See sanitizer_internal_defs.h. Imho ideally the profile library would just share that file, or just use llvm/{ADT,Support}.

[ro]

• Introduce new profile_test.h header to share the ALIGNED definition, now handling MSVC, too.
• Use it in affected tests.

Tested on sparcv9-sun-solaris2.11 and x86_64-pc-solaris2.11. I've no way of testing
on Windows, though.

[vsk]

Thanks, lgtm.

[ro]

Forgot to add Differential Revision: tag before URL, so closing manually.

test/profile/Inputs/instrprof-merge-match.c

 #include <stdint.h>
 #include <stdlib.h>
 #include <string.h>
+#include "../profile_test.h"
 
 int __llvm_profile_runtime = 0;
 uint64_t __llvm_profile_get_size_for_buffer(void);
 int __llvm_profile_write_buffer(char *);
 void __llvm_profile_reset_counters(void);
 int  __llvm_profile_check_compatibility(const char *, uint64_t);
 
 int g = 0;
 void foo(char c) {
   if (c == '1')
     g++;
   else
     g--;
 }
 
 extern uint64_t libEntry(char *Buffer, uint64_t MaxSize);
 
 int main(int argc, const char *argv[]) {
   const uint64_t MaxSize = 10000;
-  static char Buffer[MaxSize];
+  static char ALIGNED(sizeof(uint64_t)) Buffer[MaxSize];
 
   uint64_t Size = __llvm_profile_get_size_for_buffer();
   if (Size > MaxSize)
     return 1;
 
   __llvm_profile_reset_counters();
   foo('0');
 

test/profile/instrprof-merge.c

 // RUN: %clang_profgen -O2 -o %t %s
 // RUN: %run %t %t.profraw 1 1
 // RUN: llvm-profdata show --all-functions --counts %t.profraw  | FileCheck %s
 
 // FIXME: llvm-profdata exits with "Malformed instrumentation profile data"
 // XFAIL: msvc
 
 #include <stdint.h>
 #include <stdio.h>
 #include <stdlib.h>
+#include "profile_test.h"
 
 int __llvm_profile_runtime = 0;
 uint64_t __llvm_profile_get_size_for_buffer(void);
 int __llvm_profile_write_buffer(char *);
 void __llvm_profile_reset_counters(void);
 void __llvm_profile_merge_from_buffer(const char *, uint64_t);
 
 int dumpBuffer(const char *FileN, const char *Buffer, uint64_t Size) {

 void bar(int M) { g += M; }
 
 int main(int argc, const char *argv[]) {
   int i;
   if (argc < 4)
     return 1;
 
   const uint64_t MaxSize = 10000;
-  static char Buffer[MaxSize];
+  static ALIGNED(sizeof(uint64_t)) char Buffer[MaxSize];
 
   uint64_t Size = __llvm_profile_get_size_for_buffer();
   if (Size > MaxSize)
     return 1;
 
   /* Start profiling. */
   __llvm_profile_reset_counters();
   foo(argv[2][0]);

test/profile/profile_test.h

+//===-- profile_test.h.h ----------------------------------------*- 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
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains definitions for the profile tests.
+//===----------------------------------------------------------------------===//
+#ifndef PROFILE_TEST_H
+#define PROFILE_TEST_H
+
+#if defined(_MSC_VER)
+# define ALIGNED(x) __declspec(align(x))
+#else  // _MSC_VER
+# define ALIGNED(x) __attribute__((aligned(x)))
+#endif
+
+#endif  // PROFILE_TEST_H