util: add --debug-cycle to help debug print

it will enable print cycle in DPRINTF,
print tick is difficult to debug, print cycle helps,
DPRINTF print like:
  31635: system.cpu.branchPred: [c: 95] DecoupledBPUWithFTB::tick()
c: 95 means cycle, 95 = 31635 / 333, 333 is ticks for 1 cycle in 3GHz,
use cpu->clockPeriod() is greater, but not all class have cpu member.

Change-Id: I0ff1f3e3290842e6ba110393705c003616103924

SConstruct

@@ -149,6 +149,8 @@ AddOption('--pgo-prof', action='store_true',
           help='Enable pgo profiling generation')
 AddOption('--pgo-use', action='store', default=None,
           help='Use pgo profiling results')
+AddOption('--debug-cycle', action='store_true',
+          help='Enable print cycle in DPRINTF')
 
 # Inject the built_tools directory into the python path.
 sys.path[1:1] = [ Dir('#build_tools').abspath ]

src/SConscript

@@ -665,6 +665,13 @@ envs['debug'].Append(CPPDEFINES=['DEBUG', 'TRACING_ON=1'])
 envs['opt'].Append(CCFLAGS=['-g'], CPPDEFINES=['TRACING_ON=1'])
 envs['fast'].Append(CPPDEFINES=['NDEBUG', 'TRACING_ON=0'])
 
+if GetOption('debug_cycle'):
+    for target in ['debug', 'opt', 'fast']:
+        envs[target].Append(CPPDEFINES=['DEBUG_SHOW_CYCLES=1'])
+else:
+    for target in ['debug', 'opt', 'fast']:
+        envs[target].Append(CPPDEFINES=['DEBUG_SHOW_CYCLES=0'])
+
 # For Link Time Optimization, the optimisation flags used to compile
 # individual files are decoupled from those used at link time
 # (i.e. you can compile with -O3 and perform LTO with -O0), so we need

src/base/trace.hh

@@ -183,12 +183,24 @@ struct StringWrap
             ::gem5::curTick(), name(), data, count, #x); \
 } while (0)
 
-#define DPRINTF(x, ...) do {                     \
-    if (GEM5_UNLIKELY(TRACING_ON && (::gem5::debug::x))) {   \
-        ::gem5::Trace::getDebugLogger()->dprintf_flag(   \
-            ::gem5::curTick(), name(), #x, __VA_ARGS__); \
-    }                                            \
-} while (0)
+#if DEBUG_SHOW_CYCLES
+    #define DPRINTF(x, ...) do {                     \
+        if (GEM5_UNLIKELY(TRACING_ON && (::gem5::debug::x))) {   \
+            ::gem5::Trace::getDebugLogger()->dprintf_flag(   \
+                ::gem5::curTick(), name(), #x, \
+                "[c: %llu] %s", \
+                ::gem5::curTick()/333, \
+                ::gem5::csprintf(__VA_ARGS__).c_str()); \
+        }  /* todo: remove 333, use cpu->clockPeriod() */ \
+    } while (0)
+#else
+    #define DPRINTF(x, ...) do {                     \
+        if (GEM5_UNLIKELY(TRACING_ON && (::gem5::debug::x))) {   \
+            ::gem5::Trace::getDebugLogger()->dprintf_flag(   \
+                ::gem5::curTick(), name(), #x, __VA_ARGS__); \
+        }                                            \
+    } while (0)
+#endif
 
 #define DPRINTFS(x, s, ...) do {                        \
     if (GEM5_UNLIKELY(TRACING_ON && (::gem5::debug::x))) {          \