Make targets cmd able to list CPUs and features

src-self-hosted/stage1.zig

@@ -6,9 +6,12 @@ const io = std.io;
 const mem = std.mem;
 const fs = std.fs;
 const process = std.process;
+const feature = std.target.feature;
+const cpu = std.target.cpu;
 const Allocator = mem.Allocator;
 const ArrayList = std.ArrayList;
 const Buffer = std.Buffer;
+const Target = std.Target;
 const self_hosted_main = @import("main.zig");
 const errmsg = @import("errmsg.zig");
 const DepTokenizer = @import("dep_tokenizer.zig").Tokenizer;
@@ -527,3 +530,99 @@ export fn stage2_progress_update_node(node: *std.Progress.Node, done_count: usiz
     node.activate();
     node.context.maybeRefresh();
 }
+
+// ABI warning
+export fn stage2_list_features_for_arch(arch_name_ptr: [*]const u8, arch_name_len: usize, show_subfeatures: bool) void {
+    print_features_for_arch(arch_name_ptr[0..arch_name_len], show_subfeatures) catch |err| {
+        std.debug.warn("Failed to list features: {}\n", .{ @errorName(err) });
+    };
+}
+
+fn print_features_for_arch(arch_name: []const u8, show_subfeatures: bool) !void {
+    const stdout_stream = &std.io.getStdOut().outStream().stream;
+
+    const arch = Target.parseArchTag(arch_name) catch {
+        std.debug.warn("Failed to parse arch '{}'\nInvoke 'zig targets' for a list of valid architectures\n", .{ arch_name });
+        return;
+    };
+
+    inline for (@typeInfo(@TagType(Target.Arch)).Enum.fields) |arch_enum_field| {
+        if (@enumToInt(arch) == arch_enum_field.value) {
+            const enum_arch = @intToEnum(@TagType(Target.Arch), arch_enum_field.value);
+
+            const feature_infos = feature.ArchFeature(enum_arch).feature_infos;
+
+            try stdout_stream.print("Available features for {}:\n", .{ arch_enum_field.name });
+
+            var longest_len: usize = 0;
+            for (feature_infos) |feature_info| {
+                if (feature_info.name.len > longest_len) longest_len = feature_info.name.len;
+            }
+
+            for (feature_infos) |feature_info| {
+                try stdout_stream.print("  {}", .{ feature_info.name });
+                
+                var i: usize = 0;
+                while (i < longest_len - feature_info.name.len) : (i += 1) {
+                    try stdout_stream.write(" ");    
+                }
+
+                try stdout_stream.print(" - {}\n", .{ feature_info.description });
+
+                if (show_subfeatures and feature_info.subfeatures.len > 0) {
+                    for (feature_info.subfeatures) |subfeature| {
+                        try stdout_stream.print("    {}\n", .{ subfeature.getInfo().name });
+                    }
+                }
+            }
+        }
+    }
+}
+
+// ABI warning
+export fn stage2_list_cpus_for_arch(arch_name_ptr: [*]const u8, arch_name_len: usize, show_subfeatures: bool) void {
+    print_cpus_for_arch(arch_name_ptr[0..arch_name_len], show_subfeatures) catch |err| {
+        std.debug.warn("Failed to list features: {}\n", .{ @errorName(err) });
+    };
+}
+
+fn print_cpus_for_arch(arch_name: []const u8, show_subfeatures: bool) !void {
+    const stdout_stream = &std.io.getStdOut().outStream().stream;
+
+    const arch = Target.parseArchTag(arch_name) catch {
+        std.debug.warn("Failed to parse arch '{}'\nInvoke 'zig targets' for a list of valid architectures\n", .{ arch_name });
+        return;
+    };
+
+    inline for (@typeInfo(@TagType(Target.Arch)).Enum.fields) |arch_enum_field| {
+        if (@enumToInt(arch) == arch_enum_field.value) {
+            const enum_arch = @intToEnum(@TagType(Target.Arch), arch_enum_field.value);
+
+            const cpu_infos = cpu.ArchCpu(enum_arch).cpu_infos;
+
+            try stdout_stream.print("Available cpus for {}:\n", .{ arch_enum_field.name });
+
+            var longest_len: usize = 0;
+            for (cpu_infos) |cpu_info| {
+                if (cpu_info.name.len > longest_len) longest_len = cpu_info.name.len;
+            }
+
+            for (cpu_infos) |cpu_info| {
+                try stdout_stream.print("  {}", .{ cpu_info.name });
+                
+                var i: usize = 0;
+                while (i < longest_len - cpu_info.name.len) : (i += 1) {
+                    try stdout_stream.write(" ");    
+                }
+
+                try stdout_stream.write("\n");
+
+                if (show_subfeatures and cpu_info.features.len > 0) {
+                    for (cpu_info.features) |subfeature| {
+                        try stdout_stream.print("    {}\n", .{ subfeature.getInfo().name });
+                    }
+                }
+            }
+        }
+    }
+}

src/main.cpp

@@ -129,6 +129,11 @@ static int print_full_usage(const char *arg0, FILE *file, int return_code) {
         "  --test-name-prefix [text]    add prefix to all tests\n"
         "  --test-cmd [arg]             specify test execution command one arg at a time\n"
         "  --test-cmd-bin               appends test binary path to test cmd args\n"
+        "\n"
+        "Targets Options:\n"
+        "  --list-features [arch]       list available features for the given architecture\n"
+        "  --list-cpus [arch]           list available cpus for the given architecture\n"
+        "  --show-subfeatures           list subfeatures for each entry from --list-features or --list-cpus\n"
     , arg0);
     return return_code;
 }
@@ -529,6 +534,10 @@ int main(int argc, char **argv) {
     WantCSanitize want_sanitize_c = WantCSanitizeAuto;
     bool function_sections = false;
 
+    const char *targets_list_features_arch = nullptr;
+    const char *targets_list_cpus_arch = nullptr;
+    bool targets_show_subfeatures = false;
+
     ZigList<const char *> llvm_argv = {0};
     llvm_argv.append("zig (LLVM option parsing)");
 
@@ -779,6 +788,8 @@ int main(int argc, char **argv) {
                 cur_pkg = cur_pkg->parent;
             } else if (strcmp(arg, "-ffunction-sections") == 0) {
                 function_sections = true;
+            } else if (strcmp(arg, "--show-subfeatures") == 0) {
+                    targets_show_subfeatures = true;
             } else if (i + 1 >= argc) {
                 fprintf(stderr, "Expected another argument after %s\n", arg);
                 return print_error_usage(arg0);
@@ -936,7 +947,11 @@ int main(int argc, char **argv) {
                             , argv[i]);
                         return EXIT_FAILURE;
                     }
-                } else {
+                } else if (strcmp(arg, "--list-features") == 0) {
+                    targets_list_features_arch = argv[i];
+                } else if (strcmp(arg, "--list-cpus") == 0) {
+                    targets_list_cpus_arch = argv[i];
+                }else {
                     fprintf(stderr, "Invalid argument: %s\n", arg);
                     return print_error_usage(arg0);
                 }
@@ -1413,7 +1428,21 @@ int main(int argc, char **argv) {
         return main_exit(root_progress_node, EXIT_SUCCESS);
     }
     case CmdTargets:
-        return print_target_list(stdout);
+        if (targets_list_features_arch != nullptr) {
+            stage2_list_features_for_arch(
+                targets_list_features_arch,
+                strlen(targets_list_features_arch),
+                targets_show_subfeatures);
+            return 0;
+        } else if (targets_list_cpus_arch != nullptr) {
+            stage2_list_cpus_for_arch(
+                targets_list_cpus_arch,
+                strlen(targets_list_cpus_arch),
+                targets_show_subfeatures);
+            return 0;
+        } else {
+            return print_target_list(stdout);
+        }
     case CmdNone:
         return print_full_usage(arg0, stderr, EXIT_FAILURE);
     }

src/userland.cpp

@@ -88,3 +88,6 @@ void stage2_progress_end(Stage2ProgressNode *node) {}
 void stage2_progress_complete_one(Stage2ProgressNode *node) {}
 void stage2_progress_disable_tty(Stage2Progress *progress) {}
 void stage2_progress_update_node(Stage2ProgressNode *node, size_t completed_count, size_t estimated_total_items){}
+
+void stage2_list_features_for_arch(const char *arch_name_ptr, size_t arch_name_len, bool show_subfeatures) {}
+void stage2_list_cpus_for_arch(const char *arch_name_ptr, size_t arch_name_len, bool show_subfeatures) {}

src/userland.h

@@ -174,4 +174,10 @@ ZIG_EXTERN_C void stage2_progress_complete_one(Stage2ProgressNode *node);
 ZIG_EXTERN_C void stage2_progress_update_node(Stage2ProgressNode *node,
         size_t completed_count, size_t estimated_total_items);
 
+// ABI warning
+ZIG_EXTERN_C void stage2_list_features_for_arch(const char *arch_name_ptr, size_t arch_name_len, bool show_subfeatures);
+
+// ABI warning
+ZIG_EXTERN_C void stage2_list_cpus_for_arch(const char *arch_name_ptr, size_t arch_name_len, bool show_subfeatures);
+
 #endif