add command-line help descriptions on tactics

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

src/shell/main.cpp

@@ -93,6 +93,8 @@ void display_usage() {
     std::cout << "  -pd         display Z3 global (and module) parameter descriptions.\n";
     std::cout << "  -pm:name    display Z3 module ('name') parameters.\n";
     std::cout << "  -pp:name    display Z3 parameter description, if 'name' is not provided, then all module names are listed.\n";
+    std::cout << "  -tactics[:name]  display built-in tactics or if argument is given, display detailed information on tactic.\n";
+    std::cout << "  -probes     display avilable probes.\n";
     std::cout << "  --"      << "          all remaining arguments are assumed to be part of the input file name. This option allows Z3 to read files with strange names such as: -foo.smt2.\n";
     std::cout << "\nResources:\n";
     // timeout and memout are now available on Linux and macOS too.
@@ -272,6 +274,15 @@ static void parse_cmd_line_args(int argc, char ** argv) {
                     error("option argument (-memory:val) is missing.");
                 gparams::set("memory_max_size", opt_arg);
             }
+            else if (strcmp(opt_name, "tactics") == 0) {
+                if (!opt_arg)
+                    help_tactics();
+                else
+                    help_tactic(opt_arg);
+            }
+            else if (strcmp(opt_name, "probes") == 0) {
+                help_probes();
+            }
             else {
                 std::cerr << "Error: invalid command line option: " << arg << "\n";
                 std::cerr << "For usage information: z3 -h\n";

src/shell/smtlib_frontend.cpp

@@ -62,6 +62,31 @@ static void STD_CALL on_ctrl_c(int) {
     raise(SIGINT);
 }
 
+void help_tactics() {
+    cmd_context ctx;
+    for (auto cmd : ctx.tactics()) {
+        std::cout << "- " << cmd->get_name() << " " << cmd->get_descr() << "\n";
+    }
+}
+
+void help_tactic(char const* name) {
+    cmd_context ctx;
+    for (auto cmd : ctx.tactics()) {
+        if (cmd->get_name() == name) {
+            tactic_ref t = cmd->mk(ctx.m());
+            param_descrs descrs;
+            t->collect_param_descrs(descrs);
+            descrs.display(std::cout, 4);
+        }
+    }
+}
+
+void help_probes() {
+    cmd_context ctx;
+    for (auto cmd : ctx.probes()) {
+        std::cout << "- " << cmd->get_name() << " " << cmd->get_descr() << "\n";
+    }
+}
 
 unsigned read_smtlib2_commands(char const * file_name) {
     g_start_time = clock();

src/shell/smtlib_frontend.h

@@ -20,6 +20,8 @@ Revision History:
 
 unsigned read_smtlib_file(char const * benchmark_file);
 unsigned read_smtlib2_commands(char const * command_file);
-
+void help_tactics();
+void help_probes();
+void help_tactic(char const* name);