Pass the executable path into the compiler so that it can find runtim…

…e.bc even when not run from the current directory.

ast.hh

@@ -60,9 +60,12 @@ namespace Compiler
 	                         int16_t height);
 	/**
 	 * Compile the AST.  The optimisation level indicates how aggressive
-	 * optimisation should be.  Zero indicates no optimisation.
+	 * optimisation should be.  Zero indicates no optimisation.  The `path`
+	 * argument tells the compiler where to look for the `runtime.bc` file.
 	 */
-	automaton compile(AST::StatementList *ast, int optimiseLevel);
+	automaton compile(AST::StatementList *ast,
+	                  int optimiseLevel,
+	                  const std::string &path);
 }
 namespace llvm
 {

compiler.cc

@@ -83,13 +83,22 @@ struct State
 	 * file and prepares the module, including setting up all of the LLVM state
 	 * required.
 	 */
-	State() : B(C)
+	State(const std::string &path) : B(C)
 	{
+		std::string bcpath;
+		if (path.size() == 0)
+		{
+			bcpath = "runtime.bc";
+		}
+		else
+		{
+			bcpath = path + "/runtime.bc";
+		}
 		// Load the bitcode for the runtime helper code
-		auto buffer = MemoryBuffer::getFile("runtime.bc");
+		auto buffer = MemoryBuffer::getFile(bcpath);
 		if (std::error_code ec = buffer.getError())
 		{
-			std::cerr << "Failed to open runtime.bc: " << ec.message() << std::endl;
+			std::cerr << "Failed to open " << bcpath << ": " << ec.message() << std::endl;
 			exit(EXIT_FAILURE);
 		}
 		auto e = parseBitcodeFile(buffer.get()->getMemBufferRef(), C);
@@ -203,15 +212,15 @@ struct State
 
 };
 
-automaton compile(AST::StatementList *ast, int optimiseLevel)
+automaton compile(AST::StatementList *ast, int optimiseLevel, const std::string &path)
 {
 	// These functions do nothing, they just ensure that the correct modules are
 	// not removed by the linker.
 	InitializeNativeTarget();
 	InitializeNativeTargetAsmPrinter();
 	LLVMLinkInMCJIT();
 
-	State s;
+	State s(path);
 	ast->compile(s);
 	// And then return the compiled version.
 	return s.getAutomaton(optimiseLevel);

main.cc

@@ -24,6 +24,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <sys/resource.h>
+#include <libgen.h>
 #include <time.h>
 #include <unistd.h>
 #include "parser.hh"
@@ -43,6 +44,7 @@ static void logTimeSince(clock_t c1, const char *msg)
 
 int main(int argc, char **argv)
 {
+	std::string path = dirname(argv[0]);
 	int iterations = 1;
 	int useJIT = 0;
 	int optimiseLevel = 0;
@@ -141,7 +143,7 @@ int main(int argc, char **argv)
 	if (useJIT)
 	{
 		c1 = clock();
-		Compiler::automaton ca = Compiler::compile(ast.get(), optimiseLevel);
+		Compiler::automaton ca = Compiler::compile(ast.get(), optimiseLevel, path);
 		logTimeSince(c1, "Compiling");
 		c1 = clock();
 		for (int i=0 ; i<iterations ; i++)