Merge pull request #1068 from gatk555/libvvp

Configure option --enable-libvvp allows vvp to be used a shared library

Documentation/usage/index.rst

@@ -16,6 +16,7 @@ This section contains documents to help support Icarus Verilog users.
    ivlpp_flags
    vvp_flags
    vvp_debug
+   vvp_library
    vhdlpp_flags
    gtkwave
    vpi

Documentation/usage/installation.rst

@@ -99,7 +99,13 @@ time). ::
 
 This option adds extra memory cleanup code and pool management code to allow
 better memory leak checking when valgrind is available. This option is not
-need when checking for basic errors with valgrind.
+need when checking for basic errors with valgrind. ::
+
+  --enable-libvvp
+
+The vvp progam is built as a small stub linked to a shared library,
+libvvp.so, that may be linked with other programs so that they can host
+a vvp simulation.
 
 Compiling on Linux/Unix
 -----------------------

Documentation/usage/vvp_library.rst

@@ -0,0 +1,29 @@
+VVP as a library
+================
+
+If configured with ::
+
+  --enable-libvvp
+
+the vvp program will be built as a small stub that
+depends on a shared library, libvvp.so.
+The library may also be used to include a vvp simulation
+in a larger program.  Typically, the simulation communicates
+with its host program using VPI, but since
+almost all the functions of vvp are included in the library
+it may be possible to use text output and interactive mode.
+
+The accessible functions of the library are defined and documented
+in the header file, vvp/libvvp.h. Although vvp is a C++ program, the
+header file presents a C interface.
+
+Note that the vvp software was not designed to be used this way
+and the library is a straightforward recompilation of the program code.
+That imposes some restrictions, mostly arising from the use
+of static variables: only a single run of a single simulation instance
+can be expected to work without special actions.
+To mitigate these restrictions, the library may by loaded dynamically
+and unloaded at the end of each simulation run.
+Parallel simulation should be possible by making multiple copies
+of the library with different names.
+

configure.ac

@@ -170,6 +170,14 @@ AC_SUBST(HAVE_LIBBZ2)
 AC_FUNC_ALLOCA
 AC_FUNC_FSEEKO
 
+# Package Options
+# ---------------
+
+# Build VVP as a library and stub
+AC_ARG_ENABLE([libvvp],
+    [AS_HELP_STRING([--enable-libvvp], [build VVP as a shared library])],
+    [AC_SUBST(LIBVVP, yes)],[])
+
 # valgrind checks
 AC_ARG_WITH([valgrind], [AS_HELP_STRING([--with-valgrind],[Add valgrind hooks])],
             [], [check_valgrind=yes])

vvp/Makefile.in

@@ -70,7 +70,8 @@ VPI = vpi_modules.o vpi_bit.o vpi_callback.o vpi_cobject.o vpi_const.o vpi_darra
       vpi_vthr_vector.o vpip_bin.o vpip_hex.o vpip_oct.o \
       vpip_to_dec.o vpip_format.o vvp_vpi.o
 
-O = main.o parse.o parse_misc.o lexor.o arith.o array_common.o array.o bufif.o compile.o \
+O = lib_main.o \
+    parse.o parse_misc.o lexor.o arith.o array_common.o array.o bufif.o compile.o \
     concat.o dff.o class_type.o enum_type.o extend.o file_line.o latch.o npmos.o part.o \
     permaheap.o reduce.o resolv.o \
     sfunc.o stop.o \
@@ -98,7 +99,7 @@ else
 endif
 
 clean:
-	rm -f *.o *~ parse.cc parse.h lexor.cc tables.cc
+	rm -f *.o *~ parse.cc parse.h lexor.cc tables.cc libvvp.so
 	rm -rf dep vvp@EXEEXT@ parse.output vvp.man vvp.ps vvp.pdf vvp.exp
 
 distclean: clean
@@ -121,20 +122,44 @@ dep:
 	mkdir dep
 
 ifeq (@WIN32@,yes)
+ifeq (@LIBVVP@,yes)
+
+CPPFLAGS+= -fpic
+SLEXT=DLL
+
+vvp@EXEEXT@: main.o $(srcdir)/vvp.def libvvp.DLL
+	$(CXX) $(LDFLAGS) -o vvp@EXEEXT@ main.o -L. $(LDFLAGS) -lvvp $(LIBS)
+
+libvvp.DLL: $O
+	$(CXX) -shared $(LDFLAGS) -o libvvp.DLL $O $(LIBS) $(dllib)
+else
 # To support cocotb, we export the VPI functions directly. This allows
 # cocotb to build VPI modules without using our vpi_user.h and libvpi.a.
 # This requires making the vvp.exe in two steps. The first step makes
 # a vvp.exe that dlltool can use to make an export library, and the
 # second step makes a vvp.exe that really exports those things.
-vvp@EXEEXT@: $O $(srcdir)/vvp.def
-	$(CXX) -o vvp$(suffix)@EXEEXT@ $(LDFLAGS) $O $(dllib) $(LIBS)
+vvp@EXEEXT@: main.o $O $(srcdir)/vvp.def
+	$(CXX) -o vvp$(suffix)@EXEEXT@ $(LDFLAGS) main.o $O $(dllib) $(LIBS)
 	$(DLLTOOL) --dllname vvp$(suffix)@EXEEXT@ --def $(srcdir)/vvp.def \
 		--output-exp vvp.exp
 	rm -f vvp$(suffix)@EXEEXT@
-	$(CXX) $(LDFLAGS) -o vvp@EXEEXT@ vvp.exp $(LDFLAGS) $O $(dllib) $(LIBS)
+	$(CXX) $(LDFLAGS) -o vvp$(suffix)@EXEEXT@ vvp.exp $(LDFLAGS) main.o $O $(dllib) $(LIBS)
+endif
+else ifeq (@LIBVVP@,yes)
+
+CPPFLAGS+= -fpic
+SLEXT=so
+
+# To avoid setting LD_LIBRARY_PATH when running vvp from the build tree,
+# add option -Wl,-rpath=`pwd` to the CXX command below.
+vvp@EXEEXT@: main.o libvvp.so
+	$(CXX) $(LDFLAGS) -o vvp@EXEEXT@ main.o -L. -lvvp $(LIBS)
+
+libvvp.so: $O
+	$(CXX) -shared $(LDFLAGS) -o libvvp.so $O $(LIBS) $(dllib)
 else
-vvp@EXEEXT@: $O
-	$(CXX) $(LDFLAGS) -o vvp@EXEEXT@ $O $(LIBS) $(dllib)
+vvp@EXEEXT@: $O main.o
+	$(CXX) $(LDFLAGS) -o vvp@EXEEXT@ main.o $O $(LIBS) $(dllib)
 endif
 
 %.o: %.cc config.h
@@ -207,6 +232,9 @@ installpdf: vvp.pdf installdirs
 
 installfiles: $(F) | installdirs
 	$(INSTALL_PROGRAM) ./vvp@EXEEXT@ "$(DESTDIR)$(bindir)/vvp$(suffix)@EXEEXT@"
+ifeq (@LIBVVP@,yes)
+	$(INSTALL_PROGRAM) ./libvvp.$(SLEXT) "$(DESTDIR)$(libdir)/libvvp$(suffix).$(SLEXT)"
+endif
 
 installdirs: $(srcdir)/../mkinstalldirs
 	$(srcdir)/../mkinstalldirs "$(DESTDIR)$(bindir)" "$(DESTDIR)$(libdir)" "$(DESTDIR)$(INSTALL_DOCDIR)"
@@ -215,5 +243,8 @@ installdirs: $(srcdir)/../mkinstalldirs
 uninstall: $(UNINSTALL32)
 	rm -f "$(DESTDIR)$(bindir)/vvp$(suffix)@EXEEXT@"
 	rm -f "$(DESTDIR)$(mandir)/man1/vvp$(suffix).1" "$(DESTDIR)$(prefix)/vvp$(suffix).pdf"
+ifeq (@LIBVVP@,yes)
+	rm -f "$(DESTDIR)$(libdir)/libvvp$(suffix).$(SLEXT)"
+endif
 
 -include $(patsubst %.o, dep/%.d, $O)