From 3f48be3420facca86bb527ab2b4ae4126ccf1a5c Mon Sep 17 00:00:00 2001
From: Luna <git@l4.pm>
Date: Fri, 27 Sep 2019 17:18:38 -0300
Subject: [PATCH] codegen: prepare for variable emitting

---
 examples/hello.ry |  2 +-
 src/codegen.zig   | 53 +++++++++++++++++++++++++++--------------------
 2 files changed, 32 insertions(+), 23 deletions(-)

diff --git a/examples/hello.ry b/examples/hello.ry
index 9be2bf2..e935ddc 100644
--- a/examples/hello.ry
+++ b/examples/hello.ry
@@ -3,7 +3,7 @@ const (
 )
 
 fn f() i32 {
-    var a = 3;
+    // var a = 3;
     // return a;
     return 2;
 }
diff --git a/src/codegen.zig b/src/codegen.zig
index 63af360..64c7e72 100644
--- a/src/codegen.zig
+++ b/src/codegen.zig
@@ -69,6 +69,30 @@ pub const Codegen = struct {
         };
     }
 
+    fn emitForVariableType(self: *@This(), vari: var, get: var, kv: var) !llvm.LLVMValueRef {
+        var sym = kv.value;
+
+        switch (sym) {
+            .Enum => |map| {
+                var val = map.get(get.name.lexeme);
+                if (val == null) {
+                    std.debug.warn(
+                        "enum {} does not have field {}\n",
+                        vari.lexeme,
+                        get.name.lexeme,
+                    );
+                }
+                return llvm.LLVMConstInt(llvm.LLVMInt32Type(), val.?.value, 1);
+            },
+
+            .Struct => @panic("TODO handle struct"),
+            else => {
+                std.debug.warn("Invalid get target: {}\n", comp.SymbolType(sym));
+                return CompileError.EmitError;
+            },
+        }
+    }
+
     fn emitExpr(
         self: *Codegen,
         builder: var,
@@ -77,7 +101,6 @@ pub const Codegen = struct {
         // TODO if expr is Variable, we should do a variable lookup
         // in a symbol table, going up in scope, etc.
 
-        // TODO VarDecl add things to the symbol table
         // TODO Assign modify symbol table
         return switch (expr.*) {
 
@@ -136,29 +159,10 @@ pub const Codegen = struct {
                         // and emit accordingly
                         var kv_sym_opt = self.ctx.symbol_table.get(vari.lexeme);
                         if (kv_sym_opt) |kv| {
-                            var sym = kv.value;
-                            switch (sym) {
-                                .Enum => |map| {
-                                    var val = map.get(get.name.lexeme);
-                                    if (val == null) {
-                                        std.debug.warn(
-                                            "enum {} does not have field {}\n",
-                                            vari.lexeme,
-                                            get.name.lexeme,
-                                        );
-                                    }
-                                    return llvm.LLVMConstInt(llvm.LLVMInt32Type(), val.?.value, 1);
-                                },
-
-                                .Struct => @panic("TODO handle struct"),
-                                else => {
-                                    std.debug.warn("Invalid get target: {}\n", comp.SymbolType(sym));
-                                    return CompileError.EmitError;
-                                },
-                            }
+                            return try self.emitForVariableType(vari, get, kv);
                         }
 
-                        // if not, its likely a variable, we should do it accordingly
+                        // if not, its likely a variable, we should handle it accordingly
                         // as well
                         @panic("TODO handle variables");
                     },
@@ -214,6 +218,8 @@ pub const Codegen = struct {
                 return llvm.LLVMBuildStore(builder, null, assign_expr);
             },
 
+            .Variable => @panic("TODO emit variables"),
+
             else => {
                 std.debug.warn("Got unexpected expr {}\n", ast.ExprType(expr.*));
                 return CompileError.EmitError;
@@ -307,6 +313,9 @@ pub const Codegen = struct {
                 //llvm.LLVMAddIncoming(phi, &else_bb_val, &else_bb, 1);
             },
 
+            // TODO
+            .VarDecl => {},
+
             else => {
                 std.debug.warn("Got unexpected stmt {}\n", stmt.*);
                 return CompileError.EmitError;