1 files changed, 118 insertions, 0 deletions
diff --git a/libinterp/stack.c b/libinterp/stack.c
new file mode 100644
index 00000000..037d1b49
--- /dev/null
+++ b/libinterp/stack.c
@@ -0,0 +1,118 @@
+#include "lib9.h"
+#include "isa.h"
+#include "interp.h"
+#include "raise.h"
+#include <pool.h>
+
+#define T(r)	*((void**)(R.r))
+
+void
+newstack(Prog *p)
+{
+	int l;
+	Type *t;
+	Frame *f;
+	Stkext *ns;
+
+	f = T(s);
+
+	t = f->t;
+	if(t == nil)
+		t = SEXTYPE(f)->reg.TR;
+
+	f->lr = nil;
+	f->mr = nil;
+	f->fp = nil;
+	l = p->R.M->m->ss;
+	/* 16 bytes for Stkext record keeping */
+	if(l < t->size+16)
+		l = t->size+16;
+	ns = mallocz(l, 0);
+	if(ns == nil)
+		error(exNomem);
+
+	ns->reg.TR = t;
+	ns->reg.SP = nil;
+	ns->reg.TS = nil;
+	ns->reg.EX = nil;
+	p->R.EX = ns->stack;
+	p->R.TS = ns->stack + l;
+	p->R.SP = ns->reg.tos.fu + t->size;
+	p->R.FP = ns->reg.tos.fu;
+
+	memmove(p->R.FP, f, t->size);
+	f = (Frame*)p->R.FP;
+	f->t = nil;
+}
+
+void
+extend(void)
+{
+	int l;
+	Type *t;
+	Frame *f;
+	Stkext *ns;
+
+	t = R.s;
+	l = R.M->m->ss;
+	/* 16 bytes for Stkext record keeping */
+	if(l < t->size+16)
+		l = 2*t->size+16;
+	ns = mallocz(l, 0);
+	if(ns == nil)
+		error(exNomem);
+
+	ns->reg.TR = t;
+	ns->reg.SP = R.SP;
+	ns->reg.TS = R.TS;
+	ns->reg.EX = R.EX;
+	f = ns->reg.tos.fr;
+	f->t  = nil;
+	f->mr = nil;
+	R.s = f;
+	R.EX = ns->stack;
+	R.TS = ns->stack + l;
+	R.SP = ns->reg.tos.fu + t->size;
+
+	if (t->np)
+		initmem(t, f);
+}
+
+void
+unextend(Frame *f)
+{
+	Stkext *sx;
+	Type *t;
+
+	sx = SEXTYPE(f);
+	R.SP = sx->reg.SP;
+	R.TS = sx->reg.TS;
+	R.EX = sx->reg.EX;
+	t = sx->reg.TR;
+	if (t->np)
+		freeptrs(f, t);
+	free(sx);
+}
+
+void
+unframe(void)
+{
+	Type *t;
+	Frame *f;
+	Stkext *sx;
+
+	f = (Frame*)R.FP;
+	t = f->t;
+	if(t == nil)
+		t = SEXTYPE(f)->reg.TR;
+
+	R.SP = R.FP+t->size;
+
+	f = T(s);
+	if(f->t == nil) {
+		sx = SEXTYPE(f);
+		R.TS = sx->reg.TS;
+		R.EX = sx->reg.EX;
+		free(sx);
+	}
+}