commit a692421adbcc5ce8f5b20a9659cc5706c53feb1d
author Xinliang David Li <davidxl@google.com> Fri Jan 08 23:31:57 2016 +0000
committer Xinliang David Li <davidxl@google.com> Fri Jan 08 23:31:57 2016 +0000
tree 81cb5a1828da91079da5a10da060439cf7b96b47
parent 0c015c6279909990ce88253280bdd224cd7d3397

[PGO] Add runtime hook so that IR instrumentation can override version

IR level instrumentation needs to override version with variant bits.
No change for FE instrumentation is needed. Test case is added to
detect version mismatch.

llvm-svn: 257230

compiler-rt/lib/profile/InstrProfiling.c

diff --git a/compiler-rt/lib/profile/InstrProfiling.c b/compiler-rt/lib/profile/InstrProfiling.c
index 58778ae..711f2b6 100644
--- a/compiler-rt/lib/profile/InstrProfiling.c
+++ b/compiler-rt/lib/profile/InstrProfiling.c
@@ -18,6 +18,8 @@
 
 char *(*GetEnvHook)(const char *) = 0;
 
+COMPILER_RT_WEAK uint64_t __llvm_profile_raw_version = INSTR_PROF_RAW_VERSION;
+
 COMPILER_RT_VISIBILITY uint64_t __llvm_profile_get_magic(void) {
   return sizeof(void *) == sizeof(uint64_t) ? (INSTR_PROF_RAW_MAGIC_64)
                                             : (INSTR_PROF_RAW_MAGIC_32);
@@ -32,7 +34,7 @@
 }
 
 COMPILER_RT_VISIBILITY uint64_t __llvm_profile_get_version(void) {
-  return INSTR_PROF_RAW_VERSION;
+  return __llvm_profile_raw_version;
 }
 
 COMPILER_RT_VISIBILITY void __llvm_profile_reset_counters(void) {
@@ -65,4 +67,3 @@
     }
   }
 }
-

compiler-rt/lib/profile/InstrProfilingFile.c

diff --git a/compiler-rt/lib/profile/InstrProfilingFile.c b/compiler-rt/lib/profile/InstrProfilingFile.c
index bf50c02..98d85d9 100644
--- a/compiler-rt/lib/profile/InstrProfilingFile.c
+++ b/compiler-rt/lib/profile/InstrProfilingFile.c
@@ -214,6 +214,15 @@
     return -1;
   }
 
+  /* Check if there is llvm/runtime versino mismatch.  */
+  if (GET_VERSION(__llvm_profile_get_version()) != INSTR_PROF_RAW_VERSION) {
+    PROF_ERR("LLVM Profile: runtime and instrumentation version mismatch : "
+             "expected %d, but get %d\n",
+             INSTR_PROF_RAW_VERSION,
+             (int)GET_VERSION(__llvm_profile_get_version()));
+    return -1;
+  }
+
   /* Write the file. */
   rc = writeFileWithName(__llvm_profile_CurrentFilename);
   if (rc)

compiler-rt/test/profile/instrprof-version-mismatch.c

diff --git a/compiler-rt/test/profile/instrprof-version-mismatch.c b/compiler-rt/test/profile/instrprof-version-mismatch.c
new file mode 100644
index 0000000..49ce4117
--- /dev/null
+++ b/compiler-rt/test/profile/instrprof-version-mismatch.c
@@ -0,0 +1,11 @@
+// RUN: %clang_profgen -o %t -O3 %s
+// RUN: LLVM_PROFILE_VERBOSE_ERRORS=1 %run %t 1 2>&1 | FileCheck %s
+
+// override the version variable with a bogus version:
+unsigned long long __llvm_profile_raw_version = 10000;
+int main(int argc, const char *argv[]) {
+  if (argc < 2)
+    return 1;
+  return 0;
+}
+// CHECK: LLVM Profile: runtime and instrumentation version mismatch