Factor out the dummy RoCC accelerator

config.h.in

@@ -1,5 +1,8 @@
 /* config.h.in.  Generated from configure.ac by autoheader.  */
 
+/* Define if subproject MCPPBS_SPROJ_NORM is enabled */
+#undef DUMMY_ROCC_ENABLED
+
 /* Define to 1 if you have the `dl' library (-ldl). */
 #undef HAVE_LIBDL
 

configure

@@ -4301,6 +4301,51 @@ $as_echo "#define HWACHA_ENABLED /**/" >>confdefs.h
 
 
 
+    # Add subproject to our running list
+
+    subprojects="$subprojects dummy_rocc"
+
+    # Process the subproject appropriately. If enabled add it to the
+    # $enabled_subprojects running shell variable, set a
+    # SUBPROJECT_ENABLED C define, and include the appropriate
+    # 'subproject.ac'.
+
+
+      { $as_echo "$as_me:${as_lineno-$LINENO}: configuring default subproject : dummy_rocc" >&5
+$as_echo "$as_me: configuring default subproject : dummy_rocc" >&6;}
+      ac_config_files="$ac_config_files dummy_rocc.mk:dummy_rocc/dummy_rocc.mk.in"
+
+      enable_dummy_rocc_sproj="yes"
+      subprojects_enabled="$subprojects_enabled dummy_rocc"
+
+$as_echo "#define DUMMY_ROCC_ENABLED /**/" >>confdefs.h
+
+
+
+
+
+
+    # Determine if this is a required or an optional subproject
+
+
+
+    # Determine if there is a group with the same name
+
+
+
+    # Create variations of the subproject name suitable for use as a CPP
+    # enabled define, a shell enabled variable, and a shell function
+
+
+
+
+
+
+
+
+
+
+
     # Add subproject to our running list
 
     subprojects="$subprojects softfloat"
@@ -5147,6 +5192,7 @@ do
   case $ac_config_target in
     "riscv.mk") CONFIG_FILES="$CONFIG_FILES riscv.mk:riscv/riscv.mk.in" ;;
     "hwacha.mk") CONFIG_FILES="$CONFIG_FILES hwacha.mk:hwacha/hwacha.mk.in" ;;
+    "dummy_rocc.mk") CONFIG_FILES="$CONFIG_FILES dummy_rocc.mk:dummy_rocc/dummy_rocc.mk.in" ;;
     "softfloat.mk") CONFIG_FILES="$CONFIG_FILES softfloat.mk:softfloat/softfloat.mk.in" ;;
     "spike.mk") CONFIG_FILES="$CONFIG_FILES spike.mk:spike/spike.mk.in" ;;
     "config.h") CONFIG_HEADERS="$CONFIG_HEADERS config.h" ;;

configure.ac

@@ -82,7 +82,7 @@ AC_SUBST([CXXFLAGS],["-Wall -Wno-unused -O2 -std=c++11"])
 # The '*' suffix indicates an optional subproject. The '**' suffix
 # indicates an optional subproject which is also the name of a group.
 
-MCPPBS_SUBPROJECTS([ riscv, hwacha, softfloat, spike ])
+MCPPBS_SUBPROJECTS([ riscv, hwacha, dummy_rocc, softfloat, spike ])
 
 #-------------------------------------------------------------------------
 # MCPPBS subproject groups

riscv/dummy-rocc.h → dummy_rocc/dummy_rocc.cc

@@ -1,19 +1,17 @@
-#ifndef _RISCV_DUMMY_ROCC_H
-#define _RISCV_DUMMY_ROCC_H
-
 #include "rocc.h"
 #include "mmu.h"
+#include <cstring>
 
 class dummy_rocc_t : public rocc_t
 {
  public:
-  const char* name() { return "dummy"; }
+  const char* name() { return "dummy_rocc"; }
 
   reg_t custom0(rocc_insn_t insn, reg_t xs1, reg_t xs2)
   {
     reg_t prev_acc = acc[insn.rs2];
 
-    if (insn.rs2 > num_acc)
+    if (insn.rs2 >= num_acc)
       illegal_instruction();
 
     switch (insn.funct)
@@ -35,10 +33,10 @@ class dummy_rocc_t : public rocc_t
 
     return prev_acc; // in all cases, xd <- previous value of acc[rs2]
   }
-  
-  void reset()
+
+  dummy_rocc_t()
   {
-    for(int i = 0; i < num_acc; i++) acc[i] = 0;
+    memset(acc, 0, sizeof(acc));
   }
 
  private:
@@ -46,4 +44,4 @@ class dummy_rocc_t : public rocc_t
   reg_t acc[num_acc];
 };
 
-#endif
+REGISTER_EXTENSION(dummy_rocc, []() { return new dummy_rocc_t; })

dummy_rocc/dummy_rocc.mk.in

@@ -0,0 +1,7 @@
+dummy_rocc_subproject_deps = \
+	spike \
+	riscv \
+	softfloat \
+
+dummy_rocc_srcs = \
+	dummy_rocc.cc \

riscv/dummy-rocc-test.c → dummy_rocc/dummy_rocc_test.c

@@ -1,7 +1,7 @@
 // The following is a RISC-V program to test the functionality of the
 // dummy RoCC accelerator.
-// Compile with riscv-gcc dummy-rocc-test.c
-// Run with spike --extension=dummy pk a.out
+// Compile with riscv64-unknown-elf-gcc dummy_rocc_test.c
+// Run with spike --extension=dummy_rocc pk a.out
 
 #include <assert.h>
 #include <stdio.h>

hwacha/hwacha.cc

@@ -4,6 +4,8 @@
 #include "trap.h"
 #include <stdexcept>
 
+REGISTER_EXTENSION(hwacha, []() { return new hwacha_t; })
+
 void ct_state_t::reset()
 {
   nxpr = 32;

hwacha/hwacha.mk.in

@@ -1,4 +1,5 @@
 hwacha_subproject_deps = \
+	spike \
 	riscv \
 	softfloat \
 

riscv/extension.h

@@ -3,8 +3,6 @@
 
 #include "processor.h"
 #include "disasm.h"
-#include <map>
-#include <string>
 #include <vector>
 #include <functional>
 
@@ -27,11 +25,12 @@ class extension_t
   void clear_interrupt();
 };
 
-std::map<std::string, std::function<extension_t*()>>& extensions();
+std::function<extension_t*()> find_extension(const char* name);
+void register_extension(const char* name, std::function<extension_t*()> f);
 
 #define REGISTER_EXTENSION(name, constructor) \
   class register_##name { \
-    public: register_##name() { extensions()[#name] = constructor; } \
+    public: register_##name() { register_extension(#name, constructor); } \
   }; static register_##name dummy_##name;
 
 #endif

riscv/riscv.mk.in

@@ -19,7 +19,6 @@ riscv_hdrs = \
 	memtracer.h \
 	extension.h \
 	rocc.h \
-	dummy-rocc.h \
 	insn_template.h \
 	mulhi.h \
 

spike/extensions.cc

@@ -1,14 +1,35 @@
 #include "extension.h"
-#include "hwacha.h"
-#include "dummy-rocc.h"
+#include <string>
+#include <map>
+#include <dlfcn.h>
 
-REGISTER_EXTENSION(dummy, []() { return new dummy_rocc_t; })
-REGISTER_EXTENSION(hwacha, []() { return new hwacha_t; })
-
-// Static constructors want to make use of the extensions map, so we
-// access it through a function call to guarantee initialization order.
-std::map<std::string, std::function<extension_t*()>>& extensions()
+static std::map<std::string, std::function<extension_t*()>>& extensions()
 {
   static std::map<std::string, std::function<extension_t*()>> v;
   return v;
 }
+
+void register_extension(const char* name, std::function<extension_t*()> f)
+{
+  extensions()[name] = f;
+}
+
+std::function<extension_t*()> find_extension(const char* name)
+{
+  if (!extensions().count(name)) {
+    // try to find extension xyz by loading libxyz.so
+    std::string libname = std::string("lib") + name + ".so";
+    if (!dlopen(libname.c_str(), RTLD_LAZY)) {
+      fprintf(stderr, "couldn't find extension '%s' (or library '%s')\n",
+              name, libname.c_str());
+      exit(-1);
+    }
+    if (!extensions().count(name)) {
+      fprintf(stderr, "couldn't find extension '%s' in shared library '%s'\n",
+              name, libname.c_str());
+      exit(-1);
+    }
+  }
+
+  return extensions()[name];
+}

riscv/riscv-dis.cc → spike/riscv-dis.cc

@@ -21,14 +21,7 @@ int main(int argc, char** argv)
 
   std::function<extension_t*()> extension;
   option_parser_t parser;
-  parser.option(0, "extension", 1, [&](const char* s){
-    if (!extensions().count(s))
-      fprintf(stderr, "unknown extension %s!\n", s), exit(-1);
-    extension = extensions()[s];
-
-    for (auto disasm_insn : extension()->get_disasms())
-      d.add_insn(disasm_insn);
-  });
+  parser.option(0, "extension", 1, [&](const char* s){extension = find_extension(s);});
 
   while (getline(cin, s))
   {

spike/spike.cc

@@ -51,11 +51,7 @@ int main(int argc, char** argv)
   parser.option(0, "ic", 1, [&](const char* s){ic.reset(new icache_sim_t(s));});
   parser.option(0, "dc", 1, [&](const char* s){dc.reset(new dcache_sim_t(s));});
   parser.option(0, "l2", 1, [&](const char* s){l2.reset(cache_sim_t::construct(s, "L2$"));});
-  parser.option(0, "extension", 1, [&](const char* s){
-    if (!extensions().count(s))
-      fprintf(stderr, "unknown extension %s!\n", s), exit(-1);
-    extension = extensions()[s];
-  });
+  parser.option(0, "extension", 1, [&](const char* s){extension = find_extension(s);});
   parser.option(0, "extlib", 1, [&](const char *s){
     void *lib = dlopen(s, RTLD_NOW | RTLD_GLOBAL);
     if (lib == NULL) {

spike/spike.mk.in

@@ -1,7 +1,6 @@
 spike_subproject_deps = \
-	softfloat \
 	riscv \
-	hwacha \
+	softfloat \
 
 spike_install_prog_srcs = \
 	spike.cc \