From: Ulya Trofimovich <skvadrik@gmail.com>
Date: Wed, 30 Nov 2016 12:37:38 +0000 (+0000)
Subject: Skeleton: apply 'copy' commands before 'save' commands.
X-Git-Tag: 1.0~39^2~216
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=5b98063be484bc99599cdc38d266327954f3b38b;p=re2c

Skeleton: apply 'copy' commands before 'save' commands.

This is how the generated TDFA does and how it should be done.

Found by slyfox's fuzzer. :)
---

diff --git a/re2c/src/ir/skeleton/generate_data.cc b/re2c/src/ir/skeleton/generate_data.cc
index 204125e3..103b98e4 100644
--- a/re2c/src/ir/skeleton/generate_data.cc
+++ b/re2c/src/ir/skeleton/generate_data.cc
@@ -93,12 +93,12 @@ static uint32_t nsteps(uint32_t lower, uint32_t upper)
 static void apply(size_t *tags, const tcmd_t *cmd, size_t pos)
 {
 	if (!cmd) return;
-	for (const tagsave_t *p = cmd->save; p; p = p->next) {
-		tags[p->ver] = p->bottom ? Skeleton::DEFTAG : pos;
-	}
 	for (const tagcopy_t *p = cmd->copy; p; p = p->next) {
 		tags[p->lhs] = tags[p->rhs];
 	}
+	for (const tagsave_t *p = cmd->save; p; p = p->next) {
+		tags[p->ver] = p->bottom ? Skeleton::DEFTAG : pos;
+	}
 }
 
 static size_t path_width(const path_t &path, const Skeleton &skel)
diff --git a/re2c/test/tags/copy_save.i--tags.c b/re2c/test/tags/copy_save.i--tags.c
new file mode 100644
index 00000000..dbb5b417
--- /dev/null
+++ b/re2c/test/tags/copy_save.i--tags.c
@@ -0,0 +1,56 @@
+/* Generated by re2c */
+
+{
+	YYCTYPE yych;
+	if (YYLIMIT <= YYCURSOR) YYFILL(1);
+	yych = *YYCURSOR;
+	switch (yych) {
+	case 'a':
+		yyt2 = NULL;
+		yyt1 = YYCURSOR;
+		goto yy3;
+	default:
+		yyt1 = NULL;
+		goto yy2;
+	}
+yy2:
+	p = yyt1;
+	{}
+yy3:
+	++YYCURSOR;
+	if (YYLIMIT <= YYCURSOR) YYFILL(1);
+	yych = *YYCURSOR;
+	switch (yych) {
+	case 'a':
+		yyt2 = yyt1;
+		yyt1 = YYCURSOR;
+		goto yy3;
+	case 'b':	goto yy5;
+	default:	goto yy2;
+	}
+yy5:
+	YYMARKER = ++YYCURSOR;
+	if (YYLIMIT <= YYCURSOR) YYFILL(1);
+	yych = *YYCURSOR;
+	switch (yych) {
+	case 'a':	goto yy6;
+	default:
+		yyt1 = yyt2;
+		goto yy2;
+	}
+yy6:
+	++YYCURSOR;
+	if (YYLIMIT <= YYCURSOR) YYFILL(1);
+	yych = *YYCURSOR;
+	switch (yych) {
+	case 'b':	goto yy5;
+	default:	goto yy7;
+	}
+yy7:
+	YYCURSOR = YYMARKER;
+	yyt1 = yyt2;
+	goto yy2;
+}
+
+re2c: warning: line 3: rule matches empty string [-Wmatch-empty-string]
+re2c: warning: line 3: tag 'p' is nondeterministic [-Wnondeterministic-tags]
diff --git a/re2c/test/tags/copy_save.i--tags.re b/re2c/test/tags/copy_save.i--tags.re
new file mode 100644
index 00000000..acc3367b
--- /dev/null
+++ b/re2c/test/tags/copy_save.i--tags.re
@@ -0,0 +1,5 @@
+/*!re2c
+
+(@p "a")* "ab"* {}
+
+*/