MAC: Make gem5 compile and run on MacOSX 10.7.2

Adaptations to make gem5 compile and run on OSX 10.7.2, with a stock
gcc 4.2.1 and the remaining dependencies from macports, i.e. python
2.7,.2 swig 2.0.4, mercurial 2.0. The changes include an adaptation of
the SConstruct to handle non-library linker flags, and Darwin-specific
code to find the memory usage of gem5. A number of Ruby files relied
on ambigious uint (without the 32 suffix) which caused compilation
errors.

2 files changed, 37 insertions, 3 deletions

diff --git a/src/base/hostinfo.cc b/src/base/hostinfo.cc
index 5ff34e603..857ccfa7f 100644
--- a/src/base/hostinfo.cc
+++ b/src/base/hostinfo.cc
@@ -30,6 +30,12 @@
 
 #include <unistd.h>
 
+#ifdef __APPLE__
+#include <mach/mach_init.h>
+#include <mach/shared_region.h>
+#include <mach/task.h>
+#endif
+
 #include <cctype>
 #include <cerrno>
 #include <cmath>
@@ -82,7 +88,31 @@ procInfo(const char *filename, const char *target)
     }
 
     if (fp)
-      fclose(fp);
+        fclose(fp);
 
     return 0;
 }
+
+uint64_t
+memUsage()
+{
+// For the Mach-based Darwin kernel, use the task_info of the self task
+#ifdef __APPLE__
+    struct task_basic_info t_info;
+    mach_msg_type_number_t t_info_count = TASK_BASIC_INFO_COUNT;
+
+    if (KERN_SUCCESS != task_info(mach_task_self(),
+                                  TASK_BASIC_INFO, (task_info_t)&t_info,
+                                  &t_info_count)) {
+        return 0;
+    }
+
+    // Mimic Darwin's implementation of top and subtract
+    // SHARED_REGION_SIZE from the tasks virtual size to account for the
+    // shared memory submap that is incorporated into every process.
+    return (t_info.virtual_size - SHARED_REGION_SIZE) / 1024;
+#else
+    // Linux implementation
+    return procInfo("/proc/self/status", "VmSize:");
+#endif
+}
diff --git a/src/base/hostinfo.hh b/src/base/hostinfo.hh
index ac7d40f13..d9a30481a 100644
--- a/src/base/hostinfo.hh
+++ b/src/base/hostinfo.hh
@@ -39,7 +39,11 @@ std::string &hostname();
 
 uint64_t procInfo(const char *filename, const char *target);
 
-inline uint64_t memUsage()
-{ return procInfo("/proc/self/status", "VmSize:"); }
+/**
+ * Determine the simulator process' total virtual memory usage.
+ *
+ * @return virtual memory usage in kilobytes
+ */
+uint64_t memUsage();
 
 #endif // __HOSTINFO_HH__