Code Coverage using gcov

platform/retarget.cpp

@@ -72,6 +72,21 @@ extern const char __stdout_name[] = "/stdout";
 extern const char __stderr_name[] = "/stderr";
 #endif
 
+#if defined MBED_CFG_DEBUG_OPTIONS_COVERAGE
+/* Coverage sync flag used between greentea_client\source\test_env.cpp:greentea_notify_completion()
+ * and _open() to indicate that file is being open by gcov.
+ */
+bool coverage_report = false;
+
+/* Special file descriptor for gcov report. It helps in special handling of gcov report file, that
+ * is printing data on serial console rather than writing on file system.
+ */
+const int gcov_fd = 'g' + ((int)'c' << 8);
+
+extern void greentea_notify_coverage_start(const char *path);
+extern void greentea_notify_coverage_end(void);
+#endif
+
 // Heap limits - only used if set
 unsigned char *mbed_heap_start = 0;
 uint32_t mbed_heap_size = 0;
@@ -177,6 +192,14 @@ extern "C" FILEHANDLE PREFIX(_open)(const char* name, int openmode) {
         init_serial();
         return 2;
     }
+#if defined MBED_CFG_DEBUG_OPTIONS_COVERAGE
+    else if(coverage_report) {
+        init_serial();
+        // Encapsulate coverage data in greentea key,value pair.
+        greentea_notify_coverage_start(name);
+        return gcov_fd;
+    }
+#endif
     #endif
 
     // find the first empty slot in filehandles
@@ -233,7 +256,15 @@ extern "C" FILEHANDLE PREFIX(_open)(const char* name, int openmode) {
 }
 
 extern "C" int PREFIX(_close)(FILEHANDLE fh) {
-    if (fh < 3) return 0;
+    if (fh < 3)
+        return 0;
+#if defined MBED_CFG_DEBUG_OPTIONS_COVERAGE
+    else if (coverage_report && gcov_fd == fh) {
+        // Close greentea key,value encapsulation
+        greentea_notify_coverage_end();
+        return 0;
+    }
+#endif
 
     FileHandle* fhc = filehandles[fh-3];
     filehandles[fh-3] = NULL;
@@ -266,6 +297,17 @@ extern "C" int PREFIX(_write)(FILEHANDLE fh, const unsigned char *buffer, unsign
 #endif
 #endif
         n = length;
+#if defined MBED_CFG_DEBUG_OPTIONS_COVERAGE
+    } else if (coverage_report && fh == gcov_fd){
+        for (unsigned int i = 0; i < length; i++) {
+            if (0 == buffer[i]){
+                printf(".");
+            } else {
+                printf("%02x", buffer[i]);
+            }
+        }
+        n = length;
+#endif
     } else {
         FileHandle* fhc = filehandles[fh-3];
         if (fhc == NULL) return -1;
@@ -313,6 +355,10 @@ extern "C" int PREFIX(_read)(FILEHANDLE fh, unsigned char *buffer, unsigned int
 #endif
 #endif
         n = 1;
+#if defined MBED_CFG_DEBUG_OPTIONS_COVERAGE
+    } else if (coverage_report && fh == gcov_fd){
+        n = 0;
+#endif
     } else {
         FileHandle* fhc = filehandles[fh-3];
         if (fhc == NULL) return -1;
@@ -350,7 +396,13 @@ long __lseek(int fh, long offset, int whence)
 int _lseek(FILEHANDLE fh, int offset, int whence)
 #endif
 {
-    if (fh < 3) return 0;
+    if (fh < 3)
+        return 0;
+#if defined MBED_CFG_DEBUG_OPTIONS_COVERAGE
+    else if (coverage_report && fh == gcov_fd){
+        return 0;
+    }
+#endif
 
     FileHandle* fhc = filehandles[fh-3];
     if (fhc == NULL) return -1;
@@ -389,6 +441,12 @@ extern "C" int _fstat(int fd, struct stat *st) {
         st->st_mode = S_IFCHR;
         return  0;
     }
+#if defined MBED_CFG_DEBUG_OPTIONS_COVERAGE
+    else if (coverage_report && fd == gcov_fd){
+        st->st_size = 0;
+        return 0;
+    }
+#endif
 
     errno = EBADF;
     return -1;

rtos/rtx/TARGET_CORTEX_M/cmsis_os.h

@@ -88,8 +88,13 @@
 #if defined(TARGET_XDOT_L151CC)
 #define DEFAULT_STACK_SIZE         (WORDS_STACK_SIZE/2)
 #else
+#if defined (MBED_CFG_DEBUG_OPTIONS_COVERAGE)
+/* GCOV works with stack size approx. 32K. */
+#define DEFAULT_STACK_SIZE         (WORDS_STACK_SIZE*4*8)
+#else
 #define DEFAULT_STACK_SIZE         (WORDS_STACK_SIZE*4)
 #endif
+#endif
 
 #define osCMSIS           0x10002U     ///< CMSIS-RTOS API version (main [31:16] .sub [15:0])
 

targets/TARGET_Freescale/TARGET_KSDK2_MCUS/TARGET_MCU_K64F/device/TOOLCHAIN_GCC_ARM/MK64FN1M0xxx12.ld

@@ -52,9 +52,11 @@ ENTRY(Reset_Handler)
 
 __ram_vector_table__ = 1;
 
-/* Heap 1/4 of ram and stack 1/8 */
-__stack_size__ = 0x8000;
-__heap_size__ = 0x10000;
+/* Heap 1/4 of ram and stack 1/8. 0x1000 is reduced from both heap
+ * and stack to accomodate static data introduced by GCOV.
+ */
+__stack_size__ = 0x7000;
+__heap_size__ = 0x09000;
 
 HEAP_SIZE  = DEFINED(__heap_size__)  ? __heap_size__  : 0x0400;
 STACK_SIZE = DEFINED(__stack_size__) ? __stack_size__ : 0x0400;

tools/build_api.py

@@ -279,7 +279,8 @@ def prepare_toolchain(src_paths, target, toolchain_name,
                       macros=None, clean=False, jobs=1,
                       notify=None, silent=False, verbose=False,
                       extra_verbose=False, config=None,
-                      app_config=None, build_profile=None):
+                      app_config=None, build_profile=None,
+                      coverage_filter=[]):
     """ Prepares resource related objects - toolchain, target, config
 
     Positional arguments:
@@ -298,6 +299,7 @@ def prepare_toolchain(src_paths, target, toolchain_name,
     config - a Config object to use instead of creating one
     app_config - location of a chosen mbed_app.json file
     build_profile - a dict of flags that will be passed to the compiler
+    coverage_filter - list of regex to filter source files for enabling coverage
     """
 
     # We need to remove all paths which are repeated to avoid
@@ -310,9 +312,16 @@ def prepare_toolchain(src_paths, target, toolchain_name,
 
     # Toolchain instance
     try:
-        toolchain = TOOLCHAIN_CLASSES[toolchain_name](
-            target, notify, macros, silent,
-            extra_verbose=extra_verbose, build_profile=build_profile)
+        if toolchain_name == "GCC_ARM":
+            toolchain = TOOLCHAIN_CLASSES[toolchain_name](
+                target, notify, macros, silent,
+                extra_verbose=extra_verbose, build_profile=build_profile,
+                coverage_filter=coverage_filter)
+        else:
+            toolchain = TOOLCHAIN_CLASSES[toolchain_name](
+                target, notify, macros, silent,
+                extra_verbose=extra_verbose, build_profile=build_profile,
+                coverage_filter=coverage_filter)
     except KeyError:
         raise KeyError("Toolchain %s not supported" % toolchain_name)
 
@@ -362,13 +371,14 @@ def scan_resources(src_paths, toolchain, dependencies_paths=None,
 
     return resources
 
+
 def build_project(src_paths, build_path, target, toolchain_name,
                   libraries_paths=None, linker_script=None,
                   clean=False, notify=None, verbose=False, name=None,
                   macros=None, inc_dirs=None, jobs=1, silent=False,
                   report=None, properties=None, project_id=None,
                   project_description=None, extra_verbose=False, config=None,
-                  app_config=None, build_profile=None):
+                  app_config=None, build_profile=None, coverage_filter=[]):
     """ Build a project. A project may be a test or a user program.
 
     Positional arguments:
@@ -397,6 +407,7 @@ def build_project(src_paths, build_path, target, toolchain_name,
     config - a Config object to use instead of creating one
     app_config - location of a chosen mbed_app.json file
     build_profile - a dict of flags that will be passed to the compiler
+    coverage_filter - list of regex to filter source files for enabling coverage
     """
 
     # Convert src_path to a list if needed
@@ -417,7 +428,7 @@ def build_project(src_paths, build_path, target, toolchain_name,
         src_paths, target, toolchain_name, macros=macros, clean=clean,
         jobs=jobs, notify=notify, silent=silent, verbose=verbose,
         extra_verbose=extra_verbose, config=config, app_config=app_config,
-        build_profile=build_profile)
+        build_profile=build_profile, coverage_filter=coverage_filter)
 
     # The first path will give the name to the library
     if name is None:
@@ -505,13 +516,14 @@ def build_project(src_paths, build_path, target, toolchain_name,
         # Let Exception propagate
         raise
 
+
 def build_library(src_paths, build_path, target, toolchain_name,
                   dependencies_paths=None, name=None, clean=False,
                   archive=True, notify=None, verbose=False, macros=None,
                   inc_dirs=None, jobs=1, silent=False, report=None,
                   properties=None, extra_verbose=False, project_id=None,
                   remove_config_header_file=False, app_config=None,
-                  build_profile=None):
+                  build_profile=None, coverage_filter=None):
     """ Build a library
 
     Positional arguments:
@@ -536,6 +548,7 @@ def build_library(src_paths, build_path, target, toolchain_name,
     properties - UUUUHHHHH beats me
     extra_verbose - even more output!
     project_id - the name that goes in the report
+    coverage_filter - list of regex to filter source files for enabling coverage
     remove_config_header_file - delete config header file when done building
     app_config - location of a chosen mbed_app.json file
     build_profile - a dict of flags that will be passed to the compiler
@@ -563,7 +576,7 @@ def build_library(src_paths, build_path, target, toolchain_name,
         src_paths, target, toolchain_name, macros=macros, clean=clean,
         jobs=jobs, notify=notify, silent=silent, verbose=verbose,
         extra_verbose=extra_verbose, app_config=app_config,
-        build_profile=build_profile)
+        build_profile=build_profile, coverage_filter=coverage_filter)
 
     # The first path will give the name to the library
     if name is None:

tools/options.py

@@ -82,6 +82,8 @@ def get_default_options_parser(add_clean=True, add_options=True,
         parser.add_argument("--app-config", default=None, dest="app_config",
                             type=argparse_filestring_type,
                             help="Path of an app configuration file (Default is to look for 'mbed_app.json')")
+    parser.add_argument("--coverage-filter", default=[], action="append", dest="coverage_filter",
+                        help="Enable coverage on path that contains filter expression.")
 
     return parser
 

tools/test.py

@@ -194,7 +194,8 @@
                                                 notify=notify,
                                                 archive=False,
                                                 app_config=options.app_config,
-                              build_profile=profile)
+                                                build_profile=profile,
+                                                coverage_filter=options.coverage_filter)
 
                 library_build_success = True
             except ToolException, e:
@@ -221,8 +222,9 @@
                         notify=notify,
                         jobs=options.jobs,
                         continue_on_build_fail=options.continue_on_build_fail,
-                                                             app_config=options.app_config,
-                                                             build_profile=profile)
+                        app_config=options.app_config,
+                        build_profile=profile,
+                        coverage_filter=options.coverage_filter)
 
                 # If a path to a test spec is provided, write it to a file
                 if options.test_spec:

tools/test_api.py

@@ -18,7 +18,6 @@
 """
 
 import os
-import re
 import sys
 import json
 import uuid
@@ -2115,10 +2114,13 @@ def build_tests(tests, base_source_paths, build_path, target, toolchain_name,
                 clean=False, notify=None, verbose=False, jobs=1, macros=None,
                 silent=False, report=None, properties=None,
                 continue_on_build_fail=False, app_config=None,
-                build_profile=None):
+                build_profile=None, coverage_filter=[]):
     """Given the data structure from 'find_tests' and the typical build parameters,
     build all the tests
 
+    Keyword arguments:
+        coverage_filter - list of regex to filter source files for enabling coverage
+
     Returns a tuple of the build result (True or False) followed by the test
     build data structure"""
 
@@ -2159,7 +2161,9 @@ def build_tests(tests, base_source_paths, build_path, target, toolchain_name,
             'verbose': verbose,
             'app_config': app_config,
             'build_profile': build_profile,
-            'silent': True
+            'silent': True,
+            # Coverage requires main(). So if enabled on any module, enable it on test as well.
+            'coverage_filter': ".*" if coverage_filter else []
         }
 
         results.append(p.apply_async(build_test_worker, args, kwargs))