shithub: libmujs

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Alloc interned strings at the end of the string nodes.

Only use one malloc rather than two for each interned string.

--- a/jsintern.c

+++ b/jsintern.c

@@ -5,19 +5,20 @@

 struct js_StringNode

 {

-	char *string;

 	js_StringNode *left, *right;

 	int level;

+	char string[1];

 };

-static js_StringNode sentinel = { "", &sentinel, &sentinel, 0 };

+static js_StringNode sentinel = { &sentinel, &sentinel, 0, ""};

 static js_StringNode *newstringnode(const char *string, const char **result)

 {

-	js_StringNode *node = malloc(sizeof(js_StringNode));

-	node->string = strdup(string);

+	int n = strlen(string);

+	js_StringNode *node = malloc(offsetof(js_StringNode, string) + n + 1);

 	node->left = node->right = &sentinel;

 	node->level = 1;

+	strcpy(node->string, string);

 	return *result = node->string, node;

 }

@@ -91,7 +92,6 @@

 {

 	if (node->left != &sentinel) js_freestringnode(J, node->left);

 	if (node->right != &sentinel) js_freestringnode(J, node->right);

-	free(node->string);

 	free(node);

 }