factor some utility functions/data in util.c

1 files changed, 79 insertions, 0 deletions

diff --git a/lisc/util.c b/lisc/util.c
new file mode 100644
index 0000000..81857b0
--- /dev/null
+++ b/lisc/util.c
@@ -0,0 +1,79 @@
+#include "lisc.h"
+
+Typ typ[NTyp];
+int ntyp;
+Ins insb[NIns], *curi;
+
+void
+diag(char *s)
+{
+	fputs(s, stderr);
+	fputc('\n', stderr);
+	abort();
+}
+
+void *
+alloc(size_t n)
+{
+	void *p;
+
+	if (n == 0)
+		return 0;
+	p = calloc(1, n);
+	if (!p)
+		abort();
+	return p;
+}
+
+Blk *
+blocka()
+{
+	static Blk z;
+	Blk *b;
+
+	b = alloc(sizeof *b);
+	*b = z;
+	return b;
+}
+
+void
+emit(int op, int w, Ref to, Ref arg0, Ref arg1)
+{
+	if (curi == insb)
+		diag("emit: too many instructions");
+	*--curi = (Ins){op, w, to, {arg0, arg1}};
+}
+
+void
+emiti(Ins i)
+{
+	emit(i.op, i.wide, i.to, i.arg[0], i.arg[1]);
+}
+
+int
+bcnt(Bits *b)
+{
+	const uint64_t m1 = 0x5555555555555555;
+	const uint64_t m2 = 0x3333333333333333;
+	const uint64_t m3 = 0x0f0f0f0f0f0f0f0f;
+	const uint64_t m4 = 0x00ff00ff00ff00ff;
+	const uint64_t m5 = 0x0000ffff0000ffff;
+	const uint64_t m6 = 0x00000000ffffffff;
+	uint64_t tmp;
+	int z, i;
+
+	i = 0;
+	for (z=0; z<BITS; z++) {
+		tmp = b->t[z];
+		if (!tmp)
+			continue;
+		tmp = (tmp&m1) + (tmp>> 1&m1);
+		tmp = (tmp&m2) + (tmp>> 2&m2);
+		tmp = (tmp&m3) + (tmp>> 4&m3);
+		tmp = (tmp&m4) + (tmp>> 8&m4);
+		tmp = (tmp&m5) + (tmp>>16&m5);
+		tmp = (tmp&m6) + (tmp>>32&m6);
+		i += tmp;
+	}
+	return i;
+}