add error statement

editors/micro_callisto.yaml

@@ -6,7 +6,7 @@ detect:
 rules:
     - statement: "\\b(func|end|begin|asm|include|inline|if|then|elseif|else|while|do)\\b"
     - statement: "\\b(let|enable|requires|struct|version|return|const|enum|restrict)\\b"
-    - statement: "\\b(continue|break|union|alias)\\b"
+    - statement: "\\b(continue|break|union|alias|overwrite|error)\\b"
     - type:      "\\b(addr|void|u8|i8|u16|i16|u32|i32|u64|i64|size|usize|cell|array)\\b"
 
     - constant.string:

examples/error.cal

@@ -0,0 +1,10 @@
+include "cores/select.cal"
+include "std/io.cal"
+
+# will print Hello, world! on RM86, will error on Linux86
+
+version Linux86
+	error
+end
+
+"Hello, world!" printlstr

source/app.d

@@ -27,6 +27,8 @@ Flags:
 	-na        - Disables the -a flag
 	--version  - Shows the callisto version
 	-dp        - Prints parser output
+	-es        - Export all Callisto symbols (and add util functions for interacting
+	             with the Callisto stack)
 
 Backends:
 	rm86    - Real mode x86 and MS-DOS
@@ -54,6 +56,7 @@ int main(string[] args) {
 	CompilerBackend backend = new BackendLinux86();
 	bool            doDebug;
 	bool            debugParser;
+	bool            exportSymbols;
 
 	for (size_t i = 1; i < args.length; ++ i) {
 		if (args[i][0] == '-') {
@@ -158,6 +161,10 @@ int main(string[] args) {
 					debugParser = true;
 					break;
 				}
+				case "-es": {
+					exportSymbols = true;
+					break;
+				}
 				default: {
 					stderr.writefln("Unknown flag '%s'", args[i]);
 					return 1;
@@ -190,11 +197,12 @@ int main(string[] args) {
 		return 0;
 	}
 
-	auto compiler             = new Compiler();
-	compiler.backend          = backend;
-	compiler.backend.org      = org;
-	compiler.backend.orgSet   = orgSet;
-	compiler.backend.useDebug = doDebug;
+	auto compiler                  = new Compiler();
+	compiler.backend               = backend;
+	compiler.backend.org           = org;
+	compiler.backend.orgSet        = orgSet;
+	compiler.backend.useDebug      = doDebug;
+	compiler.backend.exportSymbols = exportSymbols;
 
 	versions ~= compiler.backend.GetVersions();
 

source/backends/linux86.d

@@ -160,6 +160,21 @@ class BackendLinux86 : CompilerBackend {
 		// copy static array constants
 		output ~= "call __copy_arrays\n";
 
+		// create functions for interop
+		if (exportSymbols) {
+			output ~= "
+				global cal_push
+				cal_push:
+					mov [r15], rdi
+					add r15, 8
+					ret
+				cal_pop:
+					sub r15, 8
+					mov rax, [r15]
+					ret
+			";
+		}
+
 		// jump to main
 		output ~= "jmp __calmain\n";
 	}
@@ -186,10 +201,18 @@ class BackendLinux86 : CompilerBackend {
 
 		foreach (name, var ; globals) {
 			output ~= format("__global_%s: resb %d\n", name.Sanitise(), var.Size());
+
+			if (exportSymbols) {
+				output ~= format("global __global_%s\n", name.Sanitise());
+			}
 		}
 
 		foreach (i, ref array ; arrays) {
 			output ~= format("__array_%d: resb %d\n", i, array.Size());
+
+			if (exportSymbols) {
+				output ~= format("global __array_%d\n", i);
+			}
 		}
 
 		// create array source
@@ -280,6 +303,10 @@ class BackendLinux86 : CompilerBackend {
 
 			words[node.name] = Word(false, []);
 
+			if (exportSymbols) {
+				output ~= format("global __func__%s\n", node.name.Sanitise());
+			}
+
 			output ~= format("__func__%s:\n", node.name.Sanitise());
 
 			foreach (ref inode ; node.nodes) {

source/compiler.d

@@ -16,6 +16,7 @@ class CompilerBackend {
 	bool     orgSet;
 	Compiler compiler;
 	bool     useDebug;
+	bool     exportSymbols;
 
 	abstract string[] GetVersions();
 	abstract string[] FinalCommands();
@@ -80,6 +81,7 @@ class Compiler {
 					case "return":   backend.CompileReturn(node); break;
 					case "continue": backend.CompileContinue(node); break;
 					case "break":    backend.CompileBreak(node); break;
+					case "error":    backend.Error(node.error, "Error thrown by code"); break;
 					default:         backend.CompileWord(node);
 				}
 				break;