[PGO] Ensure profile section symbols are created (linux)

- This is to handle a corner case where profile lib is linked
  in but non of the modules are instrumented (On linux, since
  we avoided the overhead to emit runtime hook use functions so
  this is the side effect of that size optimization).
- Added a profile runtime test case to cover all scenarios of
  shared library builds. 

Differential Revision: http://reviews.llvm.org/D14468

llvm-svn: 253098

3 files changed, 97 insertions, 0 deletions

diff --git a/compiler-rt/test/profile/Inputs/instrprof-shared-lib.c b/compiler-rt/test/profile/Inputs/instrprof-shared-lib.c
new file mode 100644
index 00000000000..d22b0a54a01
--- /dev/null
+++ b/compiler-rt/test/profile/Inputs/instrprof-shared-lib.c
@@ -0,0 +1,9 @@
+int g1 = 0;
+int g2 = 1;
+
+void foo(int n) {
+  if (n % 5 == 0)
+    g1++;
+  else
+    g2++;
+}
diff --git a/compiler-rt/test/profile/Inputs/instrprof-shared-main.c b/compiler-rt/test/profile/Inputs/instrprof-shared-main.c
new file mode 100644
index 00000000000..60da3b42c63
--- /dev/null
+++ b/compiler-rt/test/profile/Inputs/instrprof-shared-main.c
@@ -0,0 +1,13 @@
+extern int g1, g2;
+extern void foo(int n);
+
+int main() {
+  int i, j;
+  for (i = 0; i < 1000; i++)
+    for (j = 0; j < 1000; j++)
+      foo(i * j);
+
+  if (g2 - g1 == 280001)
+    return 0;
+  return 1;
+}
diff --git a/compiler-rt/test/profile/instrprof-shared.test b/compiler-rt/test/profile/instrprof-shared.test
new file mode 100644
index 00000000000..851578b0f2c
--- /dev/null
+++ b/compiler-rt/test/profile/instrprof-shared.test
@@ -0,0 +1,75 @@
+"""
+This test produces three shared libraries:
+
+1. libt-instr.so is instrumented
+2. libt-no-instr1.so is not instrumented
+3. libt-no-instr2.so is compiled with instrumentation enabled, but the object file is built
+   with instrumentation turned off.
+
+After the libraries are built, the main program is then built with/without instrumentation and linked
+against 3 libraries above.
+
+The test is to verify that programs linked against these shared objects with and without instrumentation
+enabled behave as expected.
+"""
+
+RUN: mkdir -p %t.d
+RUN: %clang_profgen -o %t.d/libt-instr.so -fPIC -shared %S/Inputs/instrprof-shared-lib.c
+RUN: %clang -o %t.d/libt-no-instr1.so -fPIC -shared %S/Inputs/instrprof-shared-lib.c
+RUN: %clang -c -o %t.d/instrprof-shared-lib-no-instr2.o -fPIC  %S/Inputs/instrprof-shared-lib.c
+RUN: %clang_profgen -o %t.d/libt-no-instr2.so -fPIC -shared %t.d/instrprof-shared-lib-no-instr2.o
+
+RUN: %clang_profgen -o %t-instr-instr -L%t.d -rpath %t.d -lt-instr  %S/Inputs/instrprof-shared-main.c
+RUN: %clang_profgen -o %t-instr-no-instr1 -L%t.d -rpath %t.d -lt-no-instr1  %S/Inputs/instrprof-shared-main.c
+RUN: %clang_profgen -o %t-instr-no-instr2 -L%t.d -rpath %t.d -lt-no-instr2  %S/Inputs/instrprof-shared-main.c
+RUN: %clang -o %t-no-instr1-instr -L%t.d -rpath %t.d -lt-instr  %S/Inputs/instrprof-shared-main.c
+RUN: %clang -o %t-no-instr1-no-instr1 -L%t.d -rpath %t.d -lt-no-instr1  %S/Inputs/instrprof-shared-main.c
+RUN: %clang -o %t-no-instr1-no-instr2 -L%t.d -rpath %t.d -lt-no-instr2  %S/Inputs/instrprof-shared-main.c
+RUN: %clang -c -o %t.d/instrprof-shared-main-no-instr2.o  %S/Inputs/instrprof-shared-main.c
+RUN: %clang -o %t-no-instr2-instr -L%t.d -rpath %t.d -lt-instr  %t.d/instrprof-shared-main-no-instr2.o
+RUN: %clang -o %t-no-instr2-no-instr1 -L%t.d -rpath %t.d -lt-no-instr1  %t.d/instrprof-shared-main-no-instr2.o
+RUN: %clang -o %t-no-instr2-no-instr2 -L%t.d -rpath %t.d -lt-no-instr2  %t.d/instrprof-shared-main-no-instr2.o
+
+RUN: env LLVM_PROFILE_FILE=%t-instr-instr.profraw %run %t-instr-instr
+RUN: env LLVM_PROFILE_FILE=%t-instr-no-instr1.profraw %run %t-instr-no-instr1
+RUN: env LLVM_PROFILE_FILE=%t-instr-no-instr2.profraw %run %t-instr-no-instr2
+RUN: env LLVM_PROFILE_FILE=%t-no-instr1-instr.profraw %run %t-no-instr1-instr
+RUN: env LLVM_PROFILE_FILE=%t-no-instr2-instr.profraw %run %t-no-instr2-instr
+RUN: env LLVM_PROFILE_FILE=%t-no-instr1-no-instr1.profraw %run %t-no-instr1-no-instr1
+RUN: env LLVM_PROFILE_FILE=%t-no-instr1-no-instr2.profraw %run %t-no-instr1-no-instr2
+RUN: env LLVM_PROFILE_FILE=%t-no-instr2-no-instr1.profraw %run %t-no-instr2-no-instr1
+RUN: env LLVM_PROFILE_FILE=%t-no-instr2-no-instr2.profraw %run %t-no-instr2-no-instr2
+
+RUN: llvm-profdata merge -o %t-instr-instr.profdata %t-instr-instr.profraw
+RUN: llvm-profdata merge -o %t-instr-no-instr1.profdata %t-instr-no-instr1.profraw
+RUN: llvm-profdata merge -o %t-instr-no-instr2.profdata %t-instr-no-instr2.profraw
+RUN: llvm-profdata merge -o %t-no-instr1-instr.profdata %t-no-instr1-instr.profraw
+RUN: llvm-profdata merge -o %t-no-instr2-instr.profdata %t-no-instr2-instr.profraw
+
+RUN: not llvm-profdata merge -o %t-no-instr1-no-instr1.profdata %t-no-instr1-no-instr1.profraw 2>&1 | FileCheck %s --check-prefix=MISSING-FILE
+RUN: not llvm-profdata merge -o %t-no-instr2-no-instr1.profdata %t-no-instr2-no-instr1.profraw 2>&1 | FileCheck %s --check-prefix=MISSING-FILE
+MISSING-FILE: profraw
+
+RUN: llvm-profdata show -counts --function main %t-instr-instr.profdata | grep -v 'Total\|Maximum' > %t-main-1
+RUN: llvm-profdata show -counts --function main %t-instr-no-instr1.profdata | grep -v 'Total\|Maximum' > %t-main-2
+RUN: llvm-profdata show -counts --function main %t-instr-no-instr2.profdata | grep -v 'Total\|Maximum' > %t-main-3
+RUN: llvm-profdata show -counts --function foo %t-instr-instr.profdata | grep -v 'Total\|Maximum' > %t-foo-1
+RUN: llvm-profdata show -counts --function foo %t-no-instr1-instr.profdata | grep -v 'Total\|Maximum' > %t-foo-2
+RUN: llvm-profdata show -counts --function foo %t-no-instr2-instr.profdata | grep -v 'Total\|Maximum'  > %t-foo-3
+
+RUN: %clang_profuse=%t-instr-instr.profdata -o %t-main-instr-instr.ll -S -emit-llvm %S/Inputs/instrprof-shared-main.c
+RUN: %clang_profuse=%t-instr-no-instr1.profdata -o %t-main-instr-no-instr1.ll -S -emit-llvm %S/Inputs/instrprof-shared-main.c
+RUN: %clang_profuse=%t-instr-no-instr2.profdata -o %t-main-instr-no-instr2.ll -S -emit-llvm %S/Inputs/instrprof-shared-main.c
+RUN: %clang_profuse=%t-instr-instr.profdata -o %t-lib-instr-instr.ll -S -emit-llvm %S/Inputs/instrprof-shared-lib.c
+RUN: %clang_profuse=%t-no-instr1-instr.profdata -o %t-lib-no-instr1-instr.ll -S -emit-llvm %S/Inputs/instrprof-shared-lib.c
+RUN: %clang_profuse=%t-no-instr2-instr.profdata -o %t-lib-no-instr2-instr.ll -S -emit-llvm %S/Inputs/instrprof-shared-lib.c
+RUN: %clang_profuse=%t-instr-instr.profdata -o %t-lib-instr-instr.ll -S -emit-llvm %S/Inputs/instrprof-shared-lib.c
+
+RUN: diff %t-main-instr-no-instr1.ll %t-main-instr-no-instr2.ll
+RUN: diff %t-lib-no-instr1-instr.ll %t-lib-no-instr2-instr.ll
+
+RUN: diff %t-main-1 %t-main-2
+RUN: diff %t-main-1 %t-main-3
+RUN: diff %t-foo-1 %t-foo-2
+RUN: diff %t-foo-1 %t-foo-3
+