Added basic unit test for llvm-cov.

This test compares the output of llvm-cov against a coverage file
generated by gcov. Currently, llvm-cov does not work on certain
platforms (namely big-endian architectures such as PowerPC, among
others). These platforms are marked as XFAIL for now, but will be fixed
later.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194616 91177308-0d34-0410-b5e6-96231b3b80d8

test/tools/llvm-cov/Inputs/README

@@ -0,0 +1,7 @@
+These inputs were pre-generated to allow for easier testing of llvm-cov.
+
+test.gcno and test.gcda were create by running clang:
+  clang++ -g -ftest-coverage -fprofile-arcs test.cpp
+
+test.cpp.gcov was created by running gcov 4.2.1:
+  gcov test.cpp

test/tools/llvm-cov/Inputs/test.cpp

@@ -0,0 +1,77 @@
+#include <cstdlib>
+
+bool on = false;
+int len = 42;
+double grid[10][10] = {0};
+const char * hello = "world";
+const char * world = "hello";
+
+struct A {
+  virtual void B();
+};
+
+void A::B() {}
+
+void useless() {}
+
+double more_useless() {
+  return 0;
+}
+
+int foo() {
+  on = true;
+  return 3;
+}
+
+int bar() {
+  len--;
+  return foo() + 45;
+}
+
+void assign(int ii, int jj) {
+  grid[ii][jj] = (ii+1) * (jj+1);
+}
+
+void initialize_grid() {
+  for (int ii = 0; ii < 2; ii++)
+    for (int jj = 0; jj < 2; jj++)
+      assign(ii, jj);
+}
+
+int main() {
+  initialize_grid();
+
+  int a = 2;
+  on = rand() % 2;
+  if (on) {
+    foo();
+    ++a;
+  } else {
+    bar();
+    a += rand();
+  }
+
+  for (int ii = 0; ii < 10; ++ii) {
+    switch (rand() % 5) {
+      case 0:
+        a += rand();
+        break;
+      case 1:
+      case 2:
+        a += rand() / rand();
+        break;
+      case 3:
+        a -= rand();
+        break;
+      default:
+        a = -1;
+    }
+  }
+
+  A thing;
+  for (uint64_t ii = 0; ii < 4294967296; ++ii)
+    thing.B();
+
+  return a + 8 + grid[2][3] + len;
+  return more_useless();
+}

test/tools/llvm-cov/Inputs/test.cpp.gcov

@@ -0,0 +1,82 @@
+        -:    0:Source:test.cpp
+        -:    0:Graph:test.gcno
+        -:    0:Data:test.gcda
+        -:    0:Runs:2
+        -:    0:Programs:1
+        -:    1:#include <cstdlib>
+        -:    2:
+        -:    3:bool on = false;
+        -:    4:int len = 42;
+        -:    5:double grid[10][10] = {0};
+        -:    6:const char * hello = "world";
+        -:    7:const char * world = "hello";
+        -:    8:
+        4:    9:struct A {
+        -:   10:  virtual void B();
+        -:   11:};
+        -:   12:
+8589934592:   13:void A::B() {}
+        -:   14:
+    #####:   15:void useless() {}
+        -:   16:
+        -:   17:double more_useless() {
+    #####:   18:  return 0;
+        -:   19:}
+        -:   20:
+        -:   21:int foo() {
+        2:   22:  on = true;
+        2:   23:  return 3;
+        -:   24:}
+        -:   25:
+        -:   26:int bar() {
+    #####:   27:  len--;
+    #####:   28:  return foo() + 45;
+        -:   29:}
+        -:   30:
+        8:   31:void assign(int ii, int jj) {
+        8:   32:  grid[ii][jj] = (ii+1) * (jj+1);
+        8:   33:}
+        -:   34:
+        -:   35:void initialize_grid() {
+       12:   36:  for (int ii = 0; ii < 2; ii++)
+       24:   37:    for (int jj = 0; jj < 2; jj++)
+       12:   38:      assign(ii, jj);
+        2:   39:}
+        -:   40:
+        -:   41:int main() {
+        2:   42:  initialize_grid();
+        -:   43:
+        2:   44:  int a = 2;
+        2:   45:  on = rand() % 2;
+        2:   46:  if (on) {
+        2:   47:    foo();
+        2:   48:    ++a;
+        2:   49:  } else {
+    #####:   50:    bar();
+    #####:   51:    a += rand();
+        -:   52:  }
+        -:   53:
+       44:   54:  for (int ii = 0; ii < 10; ++ii) {
+       20:   55:    switch (rand() % 5) {
+        -:   56:      case 0:
+        4:   57:        a += rand();
+        4:   58:        break;
+        -:   59:      case 1:
+        -:   60:      case 2:
+        2:   61:        a += rand() / rand();
+        2:   62:        break;
+        -:   63:      case 3:
+        6:   64:        a -= rand();
+        6:   65:        break;
+        -:   66:      default:
+        8:   67:        a = -1;
+        8:   68:    }
+       20:   69:  }
+        -:   70:
+        2:   71:  A thing;
+17179869188:   72:  for (uint64_t ii = 0; ii < 4294967296; ++ii)
+8589934592:   73:    thing.B();
+        -:   74:
+        2:   75:  return a + 8 + grid[2][3] + len;
+        -:   76:  return more_useless();
+        -:   77:}

test/tools/llvm-cov/lit.local.cfg

@@ -0,0 +1 @@
+config.suffixes = ['.test']

test/tools/llvm-cov/llvm-cov.test

@@ -0,0 +1,4 @@
+RUN: cd %p/Inputs && llvm-cov -gcno=test.gcno -gcda=test.gcda \
+RUN:   | diff test.cpp.gcov -
+
+XFAIL: ppc64-linux-gnu, s390x-linux-gnu, arm