scc

commit f9abdd7888869258a99de6ce8e1f894035a1d9e3
parent 199aaf23b5da8b9c77351d861fa37aa3f4f172e6
Author: Roberto E. Vargas Caballero <k0ga@shike2.com>
Date:   Fri, 27 Dec 2024 23:04:14 +0100

cc2: Add range() and delrange()

The range datatype enables making operations over specific
ranges of statements that will fit very well in operations
over basic blocks.

Diffstat:
M
src/cmd/scc-cc/cc2/cc2.h
 | 
2
++
M
src/cmd/scc-cc/cc2/node.c
 | 
31
+++++++++++++++++++++++++++++++

2 files changed, 33 insertions(+), 0 deletions(-)
diff --git a/src/cmd/scc-cc/cc2/cc2.h b/src/cmd/scc-cc/cc2/cc2.h
@@ -276,6 +276,8 @@ extern Node *addstmt(Node *np, int flags);
 extern Node *delstmt(void);
 extern Node *nextstmt(void);
 extern Node *insstmt(Node *, Node *, int);
+extern void delrange(Range *);
+extern Range range(Node *, Node *);
 
 /* symbol.c */
 #define TMPSYM  0
diff --git a/src/cmd/scc-cc/cc2/node.c b/src/cmd/scc-cc/cc2/node.c
@@ -185,6 +185,37 @@ newfun(Symbol *sym)
 }
 
 void
+delrange(Range *rp)
+{
+	Node *lprev, *rnext, *next, *np;
+
+	lprev = rp->begin->prev;
+	rnext = rp->end->next;
+
+	if (lprev)
+		lprev->next = rnext;
+	if (rnext)
+		rnext->prev = lprev;
+
+	for (np = rp->begin; np != rnext; np = next) {
+		next = np->next;
+		deltree(np);
+	}
+
+	rp->begin = rp->end = rp->cur = NULL;
+}
+
+Range
+range(Node *begin, Node *end)
+{
+	Range r;
+
+	r.cur = r.begin = begin;
+	r.end = end;
+	return r;
+}
+
+void
 apply(Node *(*fun)(Node *))
 {
 	if (!curfun)