X-Git-Url: http://deadsoftware.ru/gitweb?a=blobdiff_plain;f=src%2Foberon.c;h=8a84e1359dcd48f368f41cd945a76bb92a11b599;hb=cbfeec1f4192adbd7adb494ef79447366f051c20;hp=f2310db26de0ab2b1bffb82efee2a4b346bf7052;hpb=86c0ca1aafd465a3e0d4a9d6b1af661eba483ae1;p=dsw-obn.git

diff --git a/src/oberon.c b/src/oberon.c
index f2310db..8a84e13 100644
--- a/src/oberon.c
+++ b/src/oberon.c
@@ -61,7 +61,13 @@ enum {
 	IMPORT,
 	REAL,
 	CHAR,
-	STRING
+	STRING,
+	IF,
+	THEN,
+	ELSE,
+	ELSIF,
+	WHILE,
+	DO
 };
 
 // =======================================================================
@@ -380,6 +386,30 @@ oberon_read_ident(oberon_context_t * ctx)
 	{
 		ctx -> token = IS;
 	}
+	else if(strcmp(ident, "IF") == 0)
+	{
+		ctx -> token = IF;
+	}
+	else if(strcmp(ident, "THEN") == 0)
+	{
+		ctx -> token = THEN;
+	}
+	else if(strcmp(ident, "ELSE") == 0)
+	{
+		ctx -> token = ELSE;
+	}
+	else if(strcmp(ident, "ELSIF") == 0)
+	{
+		ctx -> token = ELSIF;
+	}
+	else if(strcmp(ident, "WHILE") == 0)
+	{
+		ctx -> token = WHILE;
+	}
+	else if(strcmp(ident, "DO") == 0)
+	{
+		ctx -> token = DO;
+	}
 }
 
 static void
@@ -1641,6 +1671,10 @@ oberon_make_bin_op(oberon_context_t * ctx, int token, oberon_expr_t * a, oberon_
 				|| b -> result -> class == OBERON_TYPE_INTEGER
 				|| a -> result -> class == OBERON_TYPE_REAL
 				|| b -> result -> class == OBERON_TYPE_REAL)
+			{
+				// accept
+			}
+			else
 			{
 				oberon_error(ctx, "used only with numeric types");
 			}
@@ -2845,6 +2879,9 @@ oberon_decl_seq(oberon_context_t * ctx)
 	oberon_prevent_undeclarated_procedures(ctx);
 }
 
+static void
+oberon_statement_seq(oberon_context_t * ctx);
+
 static void
 oberon_assign(oberon_context_t * ctx, oberon_expr_t * src, oberon_expr_t * dst)
 {
@@ -2877,6 +2914,78 @@ oberon_statement(oberon_context_t * ctx)
 			oberon_opt_proc_parens(ctx, item1);
 		}
 	}
+	else if(ctx -> token == IF)
+	{
+		gen_label_t * end;
+		gen_label_t * els;
+		oberon_expr_t * cond;
+
+		els = oberon_generator_reserve_label(ctx);
+		end = oberon_generator_reserve_label(ctx);
+
+		oberon_assert_token(ctx, IF);
+		cond = oberon_expr(ctx);
+		if(cond -> result -> class != OBERON_TYPE_BOOLEAN)
+		{
+			oberon_error(ctx, "condition must be boolean");
+		}
+		oberon_assert_token(ctx, THEN);
+		oberon_generate_branch(ctx, cond, false, els);
+		oberon_statement_seq(ctx);
+		oberon_generate_goto(ctx, end);
+		oberon_generate_label(ctx, els);
+
+		while(ctx -> token == ELSIF)
+		{
+			els = oberon_generator_reserve_label(ctx);
+
+			oberon_assert_token(ctx, ELSIF);
+			cond = oberon_expr(ctx);
+			if(cond -> result -> class != OBERON_TYPE_BOOLEAN)
+			{
+				oberon_error(ctx, "condition must be boolean");
+			}
+			oberon_assert_token(ctx, THEN);
+			oberon_generate_branch(ctx, cond, false, els);
+			oberon_statement_seq(ctx);
+			oberon_generate_goto(ctx, end);
+			oberon_generate_label(ctx, els);
+		}
+
+		if(ctx -> token == ELSE)
+		{
+			oberon_assert_token(ctx, ELSE);
+			oberon_statement_seq(ctx);
+		}
+
+		oberon_generate_label(ctx, end);
+		oberon_assert_token(ctx, END);		
+	}
+	else if(ctx -> token == WHILE)
+	{
+		gen_label_t * begin;
+		gen_label_t * end;
+		oberon_expr_t * cond;
+
+		begin = oberon_generator_reserve_label(ctx);
+		end = oberon_generator_reserve_label(ctx);
+
+		oberon_assert_token(ctx, WHILE);
+		oberon_generate_label(ctx, begin);
+		cond = oberon_expr(ctx);
+		if(cond -> result -> class != OBERON_TYPE_BOOLEAN)
+		{
+			oberon_error(ctx, "condition must be boolean");
+		}
+		oberon_generate_branch(ctx, cond, false, end);
+
+		oberon_assert_token(ctx, DO);
+		oberon_statement_seq(ctx);
+		oberon_generate_goto(ctx, begin);
+
+		oberon_assert_token(ctx, END);
+		oberon_generate_label(ctx, end);
+	}
 	else if(ctx -> token == RETURN)
 	{
 		oberon_assert_token(ctx, RETURN);