From: DeaDDooMER <deaddoomer@deadsoftware.ru>
Date: Fri, 4 Aug 2017 19:22:19 +0000 (+0300)
Subject: Добавлена конструкция CASE
X-Git-Url: http://deadsoftware.ru/gitweb?a=commitdiff_plain;h=2c43a7d73a91f64b1318306fa259a9337951a3a3;p=dsw-obn.git

Добавлена конструкция CASE
---

diff --git a/jvm_test.sh b/jvm_test.sh
index 0ec37e7..6519656 100755
--- a/jvm_test.sh
+++ b/jvm_test.sh
@@ -16,7 +16,7 @@ jasmin -d classes *.j
 javac -d classes rtl/*.java
 
 # -a -- for asm as comments
-#jad -o -b -noinner classes/*
+jad -o -b -noinner classes/*
 
 proguard -injars classes \
 	-libraryjars /usr/lib/jvm/java-8-openjdk/jre/lib/rt.jar \
diff --git a/notes b/notes
index 705055e..2c9c569 100644
--- a/notes
+++ b/notes
@@ -1,4 +1,3 @@
-- Нет конструкции CASE
 - Нет конструкции WITH
 
 - Нет модуля SYSTEM
diff --git a/src/backends/jvm/generator-jvm.c b/src/backends/jvm/generator-jvm.c
index 03b29f8..a107efc 100644
--- a/src/backends/jvm/generator-jvm.c
+++ b/src/backends/jvm/generator-jvm.c
@@ -1690,7 +1690,7 @@ jvm_generate_logical_or(gen_proc_t * p, oberon_expr_t * a, oberon_expr_t * b)
 	/* a OR b -- если a, то TRUE, иначе b */
 
 	push_expr(p, a);
-	jvm_generate(p, 1, 0, "ifne %s", label_name_calc_b);
+	jvm_generate(p, 1, 0, "ifeq %s", label_name_calc_b);
 	jvm_generate(p, 0, 1, "iconst_1");
 	jvm_generate(p, 0, 0, "goto %s", label_name_done);
 	jvm_generate_label(p, label_calc_b);
@@ -1709,7 +1709,7 @@ jvm_generate_logical_and(gen_proc_t * p, oberon_expr_t * a, oberon_expr_t * b)
 	/* a AND b -- если a, то b, иначе FALSE */
 
 	push_expr(p, a);
-	jvm_generate(p, 1, 0, "ifne %s", label_name_false);
+	jvm_generate(p, 1, 0, "ifeq %s", label_name_false);
 	push_expr(p, b);
 	jvm_generate(p, 0, 0, "goto %s", label_name_done);
 	jvm_generate_label(p, label_false);
diff --git a/src/oberon.c b/src/oberon.c
index 38e24a8..3b4a374 100644
--- a/src/oberon.c
+++ b/src/oberon.c
@@ -77,7 +77,9 @@ enum {
 	EXIT,
 	LBRACE,
 	RBRACE,
-	DOTDOT
+	DOTDOT,
+	CASE,
+	BAR
 };
 
 // =======================================================================
@@ -461,6 +463,10 @@ oberon_read_ident(oberon_context_t * ctx)
 	{
 		ctx -> token = EXIT;
 	}
+	else if(strcmp(ident, "CASE") == 0)
+	{
+		ctx -> token = CASE;
+	}
 }
 
 static void
@@ -822,6 +828,10 @@ oberon_read_symbol(oberon_context_t * ctx)
 			ctx -> token = RBRACE;
 			oberon_get_char(ctx);
 			break;
+		case '|':
+			ctx -> token = BAR;
+			oberon_get_char(ctx);
+			break;
 		default:
 			oberon_error(ctx, "invalid char %c", ctx -> c);
 			break;
@@ -3171,6 +3181,101 @@ oberon_assign(oberon_context_t * ctx, oberon_expr_t * src, oberon_expr_t * dst)
 	oberon_generate_assign(ctx, src, dst);
 }
 
+static oberon_expr_t *
+oberon_case_labels(oberon_context_t * ctx, oberon_expr_t * val)
+{
+	oberon_expr_t * e1;
+	oberon_expr_t * e2;
+	oberon_expr_t * cond;
+	oberon_expr_t * cond2;
+
+	e1 = (oberon_expr_t *) oberon_const_expr(ctx);
+	oberon_autocast_to(ctx, e1, val -> result);
+	
+	e2 = NULL;
+	if(ctx -> token == DOTDOT)
+	{
+		oberon_assert_token(ctx, DOTDOT);
+		e2 = (oberon_expr_t *) oberon_const_expr(ctx);
+		oberon_autocast_to(ctx, e2, val -> result);
+	}
+
+	if(e2 == NULL)
+	{
+		/* val == e1 */
+		cond = oberon_make_bin_op(ctx, EQUAL, val, e1);
+	}
+	else
+	{
+		/* val >= e1 && val <= e2 */
+		cond = oberon_make_bin_op(ctx, GEQ, val, e1);
+		cond2 = oberon_make_bin_op(ctx, LEQ, val, e2);
+		cond = oberon_make_bin_op(ctx, AND, cond, cond2);
+	}
+
+	return cond;
+}
+
+static void
+oberon_case(oberon_context_t * ctx, oberon_expr_t * val, gen_label_t * end)
+{
+	oberon_expr_t * cond;
+	oberon_expr_t * cond2;
+	gen_label_t * this_end;
+
+	if(ISEXPR(ctx -> token))
+	{
+		this_end = oberon_generator_reserve_label(ctx);
+
+		cond = oberon_case_labels(ctx, val);
+		while(ctx -> token == COMMA)
+		{
+			oberon_assert_token(ctx, COMMA);
+			/* cond || cond2 */
+			cond2 = oberon_case_labels(ctx, val);
+			cond = oberon_make_bin_op(ctx, OR, cond, cond2);
+		}
+		oberon_assert_token(ctx, COLON);
+
+		oberon_generate_branch(ctx, cond, false, this_end);
+		oberon_statement_seq(ctx);
+		oberon_generate_goto(ctx, end);
+
+		oberon_generate_label(ctx, this_end);
+	}
+}
+
+static void
+oberon_case_statement(oberon_context_t * ctx)
+{
+	oberon_expr_t * val;
+	oberon_expr_t * expr;
+	gen_label_t * end;
+
+	end = oberon_generator_reserve_label(ctx);
+
+	oberon_assert_token(ctx, CASE);
+	expr = oberon_expr(ctx);
+	val = oberon_make_temp_var_item(ctx, expr -> result);
+	oberon_assign(ctx, expr, val);
+	oberon_assert_token(ctx, OF);
+	oberon_case(ctx, val, end);
+	while(ctx -> token == BAR)
+	{
+		oberon_assert_token(ctx, BAR);
+		oberon_case(ctx, val, end);
+	}
+
+	if(ctx -> token == ELSE)
+	{
+		oberon_assert_token(ctx, ELSE);
+		oberon_statement_seq(ctx);
+	}
+
+	oberon_generate_label(ctx, end);
+	oberon_assert_token(ctx, END);
+}
+
 static void
 oberon_statement(oberon_context_t * ctx)
 {
@@ -3377,6 +3482,10 @@ oberon_statement(oberon_context_t * ctx)
 		}
 		oberon_generate_goto(ctx, ctx -> decl -> exit_label);
 	}
+	else if(ctx -> token == CASE)
+	{
+		oberon_case_statement(ctx);
+	}
 	else if(ctx -> token == RETURN)
 	{
 		oberon_assert_token(ctx, RETURN);
diff --git a/src/test.c b/src/test.c
index 25497b0..0eb787c 100644
--- a/src/test.c
+++ b/src/test.c
@@ -9,13 +9,18 @@ static char source_test[] =
 	"MODULE Test;"
 	"IMPORT Out;"
 	""
+	"VAR"
+	"  i : INTEGER;"
+	""
 	"BEGIN"
 	"  Out.Open;"
-	"  IF 8 IN { 2, 3, 7..10 } THEN"
-	"    Out.String('Yes'); Out.Ln;"
+	"  CASE 666 OF"
+	"    2, 3, 4, 5: Out.String('Zero');"
+	"  | 10..20, 24: Out.String('Holy shit');"
 	"  ELSE"
-	"    Out.String('No'); Out.Ln;"
+	"    Out.String('Something else');"
 	"  END;"
+	"  Out.Ln;"
 	"END Test."
 ;