Add temp result printing after OP_HALT

2 files changed, 26 insertions, 8 deletions

diff --git a/src/main.c b/src/main.c
index d2bbe67..598a93f 100644
--- a/src/main.c
+++ b/src/main.c
@@ -221,7 +221,7 @@ disassemble_chunk(Chunk chunk) {
     if (array_size(chunk.constants) > 0) {
         println("%s: ======= constants ======", chunk.file_name);
         for (sz i = 0; i < array_size(chunk.constants); i++) {
-            println("%s: %x{2}:  %x", chunk.file_name, i, chunk.constants[i]);
+            println("%s: %x{2}:  %x{8}", chunk.file_name, i, chunk.constants[i]);
         }
     }
 }
@@ -297,8 +297,10 @@ vm_run(VM *vm) {
                     fmod(vm->regs[src_a].f, vm->chunk->constants[src_b].f);
             } break;
             case OP_HALT: {
+                println("VM HALT -> %d", vm->regs[instruction.dst]);
                 return;
             }
+
             default: {
                 eprintln("unimplemented OP code: %d", instruction.op);
                 return;
@@ -324,9 +326,9 @@ CompResult compile_expr(Chunk *chunk, Node *node);
 
 CompResult
 compile_binary(OpCode op, Chunk *chunk, Node *node) {
+    sz reg_dst = chunk->reg_idx++;
     CompResult comp_a = compile_expr(chunk, node->left);
     CompResult comp_b = compile_expr(chunk, node->right);
-    sz reg_dst = chunk->reg_idx++;
     sz reg_a;
     sz reg_b;
     switch (comp_a.type) {
@@ -454,12 +456,28 @@ process_file(Str path) {
     array_zero(chunk.constants, 256, &bytecode_arena);
     array_zero(chunk.code, 0xffff, &bytecode_arena);
     sz n_roots = array_size(parser.nodes);
+    CompResult res;
     for (sz i = 0; i < n_roots; i++) {
         // The parser stores the root nodes as a stack.
         Node *root = parser.nodes[i];
-        compile_expr(&chunk, root);
+        res = compile_expr(&chunk, root);
+    }
+    sz res_reg = 0;
+    switch (res.type) {
+        case COMP_CONST: {
+            res_reg = chunk.reg_idx++;
+            Instruction inst =
+                (Instruction){.op = OP_LD64K, .dst = res_reg, .a = res.idx};
+            array_push(chunk.code, inst, chunk.storage);
+        } break;
+        case COMP_REG: {
+            res_reg = res.idx;
+        } break;
+        default: break;
     }
-    array_push(chunk.code, (Instruction){.op = OP_HALT}, &bytecode_arena);
+    // After we are done move the last result to r0 for printing.
+    Instruction halt = (Instruction){.op = OP_HALT, .dst = res_reg};
+    array_push(chunk.code, halt, &bytecode_arena);
 
     // Run bytecode on VM.
     VM vm = {0};
diff --git a/tests/expressions.bad b/tests/expressions.bad
index 512da0a..3fc9431 100644
--- a/tests/expressions.bad
+++ b/tests/expressions.bad
@@ -1,10 +1,10 @@
 ; 1 + -2
-69 + 1
+69 + 1 + 2
 
-; 1 + 2 * 3
+1 + 2 * 3
 
-; 1 + 2 * 3 - 4
+1 + 2 * 3 - 4
 
-; 1 + 2 * (3 - 4)
+1 + 2 * (3 - 4)
 
 ; 1.0 - 1234.56e-3