Add --get-supported to determine what features are in Verilator (#3688).

Changes

@@ -35,6 +35,7 @@ Verilator 5.001 devel
 * Support tristate select/extend (#3604). [Ryszard Rozak, Antmicro Ltd>
 * Support linting for top module interfaces (#3635). [Kanad Kanhere]
 * Add --dump-tree-dot to enable dumping Ast Tree .dot files (#3636). [Marcel Chang]
+* Add --get-supported to determine what features are in Verilator.
 * Add error on real edge event control.
 * Fix LSB error on --hierarchical submodules (#3539). [danbone]
 * Fix $display of fixed-width numbers (#3565). [Iztok Jeras]

bin/verilator

@@ -335,6 +335,7 @@ detailed descriptions of these arguments.
     --gdbbt                     Run Verilator under GDB for backtrace
     --generate-key              Create random key for --protect-key
     --getenv <var>              Get environment variable with defaults
+    --get-supported <feature>   Get if feature is supported
     --help                      Display this help
     --hierarchical              Enable hierarchical Verilation
      -I<dir>                    Directory to search for includes

docs/guide/exe_verilator.rst

@@ -648,6 +648,15 @@ Summary:
    a newline and exit immediately. This can be useful in makefiles. See
    also :vlopt:`-V`, and the various :file:`*.mk` files.
 
+.. option:: --get-supported <feature>
+
+   If the given feature is supported, print "1" and exit
+   immediately. Otherwise, print a newline and exit immediately. This can
+   be useful in makefiles. See also :vlopt:`-V`, and the various
+   :file:`*.mk` files.
+
+   Feature may be one of the following: COROUTINES, SYSTEMC.
+
 .. option:: --help
 
    Displays this message and program version and exits.

examples/cmake_hello_sc/Makefile

@@ -39,30 +39,12 @@ ifneq ($(CMAKE_GT_3_8),true)
 TARGET := oldcmake
 else
 
-# Test existence of SYSTEMC_INCLUDE and SYSTEMC_LIBDIR environment variabless
-ifneq (,$(SYSTEMC_INCLUDE))
-ifneq (,${SYSTEMC_LIBDIR})
-SYSTEMC_SET := true
-endif
-endif
-
-# Test existence of SYSTEMC_ROOT environment variable
-ifneq (SYSTEMC_SET, true)
-ifneq (,${SYSTEMC_ROOT})
-SYSTEMC_SET := true
-endif
-endif
-
-# Test existence of SYSTEMC environment variable
-ifneq (SYSTEMC_SET, true)
-ifneq (,${SYSTEMC})
-SYSTEMC_SET := true
-endif
-endif
+# Check if SC exists via a verilator call (empty if not)
+SYSTEMC_EXISTS := $(shell $(VERILATOR) --get-supported SYSTEMC)
 
 # Test whether SystemC is installed with CMake support
 # This will print a CMake error about processing arguments that can (currently) be ignored.
-ifneq (SYSTEMC_SET, true)
+ifneq (,$(SYSTEMC_EXISTS))
 FINDSC := $(shell mkdir -p build && cd build && cmake --find-package -DNAME=SystemCLanguage -DCMAKE_USE_PTHREADS_INIT=ON -DCOMPILER_ID=GNU -DLANGUAGE=CXX -DMODE=EXIST -DThreads_FOUND=ON)
 ifneq (,$(findstring SystemCLanguage found,$(FINDSC)))
 SYSTEMC_SET := true

examples/cmake_tracing_sc/Makefile

@@ -39,30 +39,12 @@ ifneq ($(CMAKE_GT_3_8),true)
 TARGET := oldcmake
 else
 
-# Test existence of SYSTEMC_INCLUDE and SYSTEMC_LIBDIR environment variabless
-ifneq (,$(SYSTEMC_INCLUDE))
-ifneq (,${SYSTEMC_LIBDIR})
-SYSTEMC_SET := true
-endif
-endif
-
-# Test existence of SYSTEMC_ROOT environment variable
-ifneq (SYSTEMC_SET, true)
-ifneq (,${SYSTEMC_ROOT})
-SYSTEMC_SET := true
-endif
-endif
-
-# Test existence of SYSTEMC environment variable
-ifneq (SYSTEMC_SET, true)
-ifneq (,${SYSTEMC})
-SYSTEMC_SET := true
-endif
-endif
+# Check if SC exists via a verilator call (empty if not)
+SYSTEMC_EXISTS := $(shell $(VERILATOR) --get-supported SYSTEMC)
 
 # Test whether SystemC is installed with CMake support
 # This will print a CMake error about processing arguments that can (currently) be ignored.
-ifneq (SYSTEMC_SET, true)
+ifneq (,$(SYSTEMC_EXISTS))
 FINDSC := $(shell mkdir -p build && cd build && cmake --find-package -DNAME=SystemCLanguage -DCMAKE_USE_PTHREADS_INIT=ON -DCOMPILER_ID=GNU -DLANGUAGE=CXX -DMODE=EXIST -DThreads_FOUND=ON)
 ifneq (,$(findstring SystemCLanguage found,$(FINDSC)))
 SYSTEMC_SET := true

examples/make_hello_sc/Makefile

@@ -33,7 +33,7 @@ VERILATOR = $(VERILATOR_ROOT)/bin/verilator
 endif
 
 # Check if SC exists via a verilator call (empty if not)
-SYSTEMC_EXISTS := $(shell $(VERILATOR) --getenv SYSTEMC_INCLUDE)
+SYSTEMC_EXISTS := $(shell $(VERILATOR) --get-supported SYSTEMC)
 
 ifneq ($(SYSTEMC_EXISTS),)
 default: run

examples/make_tracing_sc/Makefile

@@ -55,7 +55,7 @@ VERILATOR_FLAGS += --coverage
 VERILATOR_INPUT = -f input.vc top.v sc_main.cpp
 
 # Check if SC exists via a verilator call (empty if not)
-SYSTEMC_EXISTS := $(shell $(VERILATOR) --getenv SYSTEMC_INCLUDE)
+SYSTEMC_EXISTS := $(shell $(VERILATOR) --get-supported SYSTEMC)
 
 ######################################################################
 

src/V3Options.cpp

@@ -604,6 +604,7 @@ V3LangCode V3Options::fileLanguage(const string& filename) {
 // Environment
 
 string V3Options::getenvBuiltins(const string& var) {
+    // If update below, also update V3Options::showVersion()
     if (var == "MAKE") {
         return getenvMAKE();
     } else if (var == "PERL") {
@@ -711,6 +712,17 @@ string V3Options::getenvVERILATOR_ROOT() {
     return var;
 }
 
+string V3Options::getSupported(const string& var) {
+    // If update below, also update V3Options::showVersion()
+    if (var == "COROUTINES" && coroutineSupport()) {
+        return "1";
+    } else if (var == "SYSTEMC" && systemCFound()) {
+        return "1";
+    } else {
+        return "";
+    }
+}
+
 bool V3Options::systemCSystemWide() {
 #ifdef HAVE_SYSTEMC
     return true;
@@ -1179,6 +1191,10 @@ void V3Options::parseOptsList(FileLine* fl, const string& optdir, int argc, char
         cout << V3Options::getenvBuiltins(valp) << endl;
         std::exit(0);
     });
+    DECL_OPTION("-get-supported", CbVal, [](const char* valp) {
+        cout << V3Options::getSupported(valp) << endl;
+        std::exit(0);
+    });
 
     DECL_OPTION("-hierarchical", OnOff, &m_hierarchical);
     DECL_OPTION("-hierarchical-block", CbVal, [this](const char* valp) {
@@ -1800,6 +1816,7 @@ void V3Options::showVersion(bool verbose) {
     cout << "    VERILATOR_ROOT     = " << DEFENV_VERILATOR_ROOT << endl;
     cout << "    SystemC system-wide = " << cvtToStr(systemCSystemWide()) << endl;
 
+    // If update below, also update V3Options::getenvBuiltins()
     cout << endl;
     cout << "Environment:\n";
     cout << "    MAKE               = " << V3Os::getenvStr("MAKE", "") << endl;
@@ -1812,10 +1829,11 @@ void V3Options::showVersion(bool verbose) {
     cout << "    VERILATOR_BIN      = " << V3Os::getenvStr("VERILATOR_BIN", "") << endl;
     cout << "    VERILATOR_ROOT     = " << V3Os::getenvStr("VERILATOR_ROOT", "") << endl;
 
+    // If update below, also update V3Options::getSupported()
     cout << endl;
-    cout << "Features (based on environment or compiled-in support):\n";
-    cout << "    SystemC found      = " << cvtToStr(systemCFound()) << endl;
-    cout << "    Coroutine support  = " << cvtToStr(coroutineSupport()) << endl;
+    cout << "Supported features (compiled-in or forced by environment):\n";
+    cout << "    COROUTINES         = " << getSupported("COROUTINES") << endl;
+    cout << "    SYSTEMC            = " << getSupported("SYSTEMC") << endl;
 }
 
 //======================================================================

src/V3Options.h

@@ -666,6 +666,7 @@ public:
     static string getenvSYSTEMC_INCLUDE();
     static string getenvSYSTEMC_LIBDIR();
     static string getenvVERILATOR_ROOT();
+    static string getSupported(const string& var);
     static bool systemCSystemWide();
     static bool systemCFound();  // SystemC installed, or environment points to it
     static bool coroutineSupport();  // Compiler supports coroutines

test_regress/driver.pl

@@ -1476,13 +1476,13 @@ sub sc {
 sub have_sc {
     my $self = (ref $_[0] ? shift : $Self);
     return 1 if (defined $ENV{SYSTEMC} || defined $ENV{SYSTEMC_INCLUDE} || $ENV{CFG_HAVE_SYSTEMC});
-    return 1 if $self->verilator_version =~ /systemc found *= *1/i;
+    return 1 if $self->verilator_get_supported('SYSTEMC');
     return 0;
 }
 
 sub have_coroutines {
     my $self = (ref $_[0] ? shift : $Self);
-    return 1 if $self->verilator_version =~ /coroutine support *= *1/i;
+    return 1 if $self->verilator_get_supported('COROUTINES');
     return 0;
 }
 
@@ -2162,17 +2162,20 @@ sub _read_inputs_vhdl {
 #######################################################################
 # Verilator utilities
 
-our $_Verilator_Version;
-sub verilator_version {
-    # Returns verbose version, line 1 contains actual version
-    if (!defined $_Verilator_Version) {
-        my @args = ("perl", "$ENV{VERILATOR_ROOT}/bin/verilator", "-V");
+our %_Verilator_Supported;
+sub verilator_get_supported {
+    my $self = (ref $_[0] ? shift : $Self);
+    my $feature = shift;
+    # Returns if given feature is supported
+    if (!defined $_Verilator_Supported{$feature}) {
+        my @args = ("perl", "$ENV{VERILATOR_ROOT}/bin/verilator", "-get-supported", $feature);
         my $args = join(' ', @args);
-        $_Verilator_Version = `$args`;
-        $_Verilator_Version or die "can't fork: $! " . join(' ', @args);
-        chomp $_Verilator_Version;
+        my $out = `$args`;
+        $out or die "couldn't run: $! " . join(' ', @args);
+        chomp $out;
+        $_Verilator_Supported{$feature} = ($out =~ /1/ ? 1 : 0);
     }
-    return $_Verilator_Version if defined $_Verilator_Version;
+    return $_Verilator_Supported{$feature};
 }
 
 #######################################################################

test_regress/t/t_flag_supported.pl

@@ -0,0 +1,42 @@
+#!/usr/bin/env perl
+if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); die; }
+# DESCRIPTION: Verilator: Verilog Test driver/expect definition
+#
+# Copyright 2008 by Wilson Snyder. This program is free software; you
+# can redistribute it and/or modify it under the terms of either the GNU
+# Lesser General Public License Version 3 or the Perl Artistic License
+# Version 2.0.
+# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+
+scenarios(vlt => 1);
+
+if ($Self->have_coroutines) {
+    run(
+        cmd => ["../bin/verilator --get-supported COROUTINES"],
+        expect => '1
+',
+        logfile => "$Self->{obj_dir}/vlt_coroutines.log",
+        verilator_run => 1,
+        );
+}
+
+if ($Self->have_sc) {
+    run(
+        cmd => ["../bin/verilator --get-supported SYSTEMC"],
+        expect => '1
+',
+        logfile => "$Self->{obj_dir}/vlt_systemc.log",
+        verilator_run => 1,
+        );
+}
+
+run(
+    cmd => ["../bin/verilator --get-supported DOES_NOT_EXIST"],
+    expect => '',
+    logfile => "$Self->{obj_dir}/vlt_does_not_exist.log",
+    verilator_run => 1,
+    );
+
+
+ok(1);
+1;