util: add m5_fail op.

Used as a command in full-system scripts helps the user ensure the benchmarks have finished successfully.

For example, one can use:

    /path/to/benchmark args || /sbin/m5 fail 1

and thus ensure gem5 will exit with an error if the benchmark fails.

configs/common/Simulation.py

@@ -27,6 +27,7 @@
 #
 # Authors: Lisa Hsu
 
+import sys
 from os import getcwd
 from os.path import join as joinpath
 
@@ -505,3 +506,5 @@ def run(options, root, testsys, cpu_class):
     print 'Exiting @ tick %i because %s' % (m5.curTick(), exit_cause)
     if options.checkpoint_at_end:
         m5.checkpoint(joinpath(cptdir, "cpt.%d"))
+
+    sys.exit(exit_event.getCode())

src/arch/x86/isa/decoder/two_byte_opcodes.isa

@@ -157,6 +157,9 @@
                         0x21: m5exit({{
                             PseudoInst::m5exit(xc->tcBase(), Rdi);
                         }}, IsNonSpeculative);
+                        0x22: m5fail({{
+                            PseudoInst::m5fail(xc->tcBase(), Rdi, Rsi);
+                        }}, IsNonSpeculative);
                         0x30: m5initparam({{
                             Rax = PseudoInst::initParam(xc->tcBase());
                         }}, IsNonSpeculative);

src/sim/pseudo_inst.cc

@@ -218,6 +218,13 @@ m5exit(ThreadContext *tc, Tick delay)
     exitSimLoop("m5_exit instruction encountered", 0, when);
 }
 
+void
+m5fail(ThreadContext *tc, Tick delay, uint64_t code)
+{
+    Tick when = curTick() + delay * SimClock::Int::ns;
+    exitSimLoop("m5_fail instruction encountered", code, when);
+}
+
 void
 loadsymbol(ThreadContext *tc)
 {

src/sim/pseudo_inst.hh

@@ -54,6 +54,7 @@ uint64_t initParam(ThreadContext *xc);
 uint64_t rpns(ThreadContext *tc);
 void wakeCPU(ThreadContext *tc, uint64_t cpuid);
 void m5exit(ThreadContext *tc, Tick delay);
+void m5fail(ThreadContext *tc, Tick delay, uint64_t code);
 void resetstats(ThreadContext *tc, Tick delay, Tick period);
 void dumpstats(ThreadContext *tc, Tick delay, Tick period);
 void dumpresetstats(ThreadContext *tc, Tick delay, Tick period);

util/m5/m5.c

@@ -134,6 +134,15 @@ do_exit(int argc, char *argv[])
     m5_exit(ints[0]);
 }
 
+void
+do_fail(int argc, char *argv[])
+{
+    if (argc < 1 || argc > 2)
+        usage();
+
+    m5_fail((argc > 1) ? strtoul(argv[1], NULL, 0) : 0, strtoul(argv[0], NULL, 0));
+}
+
 void
 do_reset_stats(int argc, char *argv[])
 {
@@ -273,6 +282,7 @@ struct MainFunc
 
 struct MainFunc mainfuncs[] = {
     { "exit",           do_exit,             "[delay]" },
+    { "fail",           do_fail,             "<code> [delay]" },
     { "resetstats",     do_reset_stats,      "[delay [period]]" },
     { "dumpstats",      do_dump_stats,       "[delay [period]]" },
     { "dumpresetstats", do_dump_reset_stats, "[delay [period]]" },

util/m5/m5op.h

@@ -47,6 +47,7 @@ uint64_t rpns();
 void wakeCPU(uint64_t cpuid);
 
 void m5_exit(uint64_t ns_delay);
+void m5_fail(uint64_t ns_delay, uint64_t code);
 uint64_t m5_initparam(void);
 void m5_checkpoint(uint64_t ns_delay, uint64_t ns_period);
 void m5_reset_stats(uint64_t ns_delay, uint64_t ns_period);

util/m5/m5op_x86.S

@@ -48,6 +48,7 @@ TWO_BYTE_OP(quiesceCycle, quiescecycle_func)
 TWO_BYTE_OP(quiesceTime, quiescetime_func)
 TWO_BYTE_OP(rpns, rpns_func)
 TWO_BYTE_OP(m5_exit, exit_func)
+TWO_BYTE_OP(m5_fail, fail_func)
 TWO_BYTE_OP(m5_initparam, initparam_func)
 TWO_BYTE_OP(m5_loadsymbol, loadsymbol_func)
 TWO_BYTE_OP(m5_reset_stats, resetstats_func)

util/m5/m5ops.h

@@ -40,6 +40,7 @@
 #define deprecated2_func        0x11 // obsolete ivle
 #define deprecated3_func        0x20 // deprecated exit function
 #define exit_func               0x21
+#define fail_func               0x22
 #define initparam_func          0x30
 #define loadsymbol_func         0x31
 #define resetstats_func         0x40