From c4de24981ae56b43841d4d71bf73ee9af00ee281 Mon Sep 17 00:00:00 2001
From: Ken Thompson <ken@golang.org>
Date: Tue, 5 May 2009 21:19:58 -0700
Subject: [PATCH] signs on div and mod

R=r
OCL=28319
CL=28319
---
 src/cmd/gc/mparith2.c |  14 +++-
 test/ken/divmod.go    | 184 ++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 197 insertions(+), 1 deletion(-)
 create mode 100644 test/ken/divmod.go

diff --git a/src/cmd/gc/mparith2.c b/src/cmd/gc/mparith2.c
index 9be8a16b78..0887c5b43e 100644
--- a/src/cmd/gc/mparith2.c
+++ b/src/cmd/gc/mparith2.c
@@ -570,7 +570,12 @@ mpmovecfix(Mpint *a, vlong c)
 void
 mpdivmodfixfix(Mpint *q, Mpint *r, Mpint *n, Mpint *d)
 {
-	int i;
+	int i, ns, ds;
+
+	ns = n->neg;
+	ds = d->neg;
+	n->neg = 0;
+	d->neg = 0;
 
 	mpmovefixfix(r, n);
 	mpmovecfix(q, 0);
@@ -588,6 +593,8 @@ mpdivmodfixfix(Mpint *q, Mpint *r, Mpint *n, Mpint *d)
 	if(i >= Mpprec*Mpscale) {
 		q->ovf = 1;
 		r->ovf = 1;
+		n->neg = ns;
+		d->neg = ds;
 		yyerror("set ovf in mpdivmodfixfix");
 		return;
 	}
@@ -604,6 +611,11 @@ mpdivmodfixfix(Mpint *q, Mpint *r, Mpint *n, Mpint *d)
 			mpsubfixfix(r, d);
 		}
 	}
+
+	n->neg = ns;
+	d->neg = ds;
+	r->neg = ns;
+	q->neg = ns^ds;
 }
 
 void
diff --git a/test/ken/divmod.go b/test/ken/divmod.go
new file mode 100644
index 0000000000..a2821db29a
--- /dev/null
+++ b/test/ken/divmod.go
@@ -0,0 +1,184 @@
+// $G $D/$F.go && $L $F.$A && ./$A.out
+
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+const
+(
+	n1	= +5;
+	n2	= -5;
+	d1	= +3;
+	d2	= -3;
+
+	q1	= +1;
+	q2	= -1;
+	q3	= -1;
+	q4	= +1;
+
+	r1	= +2;
+	r2	= -2;
+	r3	= +2;
+	r4	= -2;
+)
+
+func
+main()
+{
+	/* ideals */
+	if n1/d1 != q1 || n1%d1 != r1 {
+		panicln(n1, d1, n1/d1, n1%d1);
+	}
+	if n2/d1 != q2 || n2%d1 != r2 {
+		panicln(n2, d1, n2/d1, n2%d1);
+	}
+	if n1/d2 != q3 || n1%d2 != r3 {
+		panicln(n1, d2, n1/d2, n1%d2);
+	}
+	if n2/d2 != q4 || n2%d2 != r4 {
+		panicln(n2, d2, n2/d2, n2%d2);
+	}
+
+	/* int */
+	var in1 int = +5;
+	var in2 int = -5;
+	var id1 int = +3;
+	var id2 int = -3;
+
+	if in1/id1 != q1 || in1%id1 != r1 {
+		panicln(in1, id1, in1/id1, in1%id1);
+	}
+	if in2/id1 != q2 || in2%id1 != r2 {
+		panicln(in2, id1, in2/id1, in2%id1);
+	}
+	if in1/id2 != q3 || in1%id2 != r3 {
+		panicln(in1, id2, in1/id2, in1%id2);
+	}
+	if in2/id2 != q4 || in2%id2 != r4 {
+		panicln(in2, id2, in2/id2, in2%id2);
+	}
+
+	/* int8 */
+	var bn1 int8 = +5;
+	var bn2 int8 = -5;
+	var bd1 int8 = +3;
+	var bd2 int8 = -3;
+
+	if bn1/bd1 != q1 || bn1%bd1 != r1 {
+		panicln(bn1, bd1, bn1/bd1, bn1%bd1);
+	}
+	if bn2/bd1 != q2 || bn2%bd1 != r2 {
+		panicln(bn2, bd1, bn2/bd1, bn2%bd1);
+	}
+	if bn1/bd2 != q3 || bn1%bd2 != r3 {
+		panicln(bn1, bd2, bn1/bd2, bn1%bd2);
+	}
+	if bn2/bd2 != q4 || bn2%bd2 != r4 {
+		panicln(bn2, bd2, bn2/bd2, bn2%bd2);
+	}
+
+	/* int16 */
+	var sn1 int16 = +5;
+	var sn2 int16 = -5;
+	var sd1 int16 = +3;
+	var sd2 int16 = -3;
+
+	if sn1/sd1 != q1 || sn1%sd1 != r1 {
+		panicln(sn1, sd1, sn1/sd1, sn1%sd1);
+	}
+	if sn2/sd1 != q2 || sn2%sd1 != r2 {
+		panicln(sn2, sd1, sn2/sd1, sn2%sd1);
+	}
+	if sn1/sd2 != q3 || sn1%sd2 != r3 {
+		panicln(sn1, sd2, sn1/sd2, sn1%sd2);
+	}
+	if sn2/sd2 != q4 || sn2%sd2 != r4 {
+		panicln(sn2, sd2, sn2/sd2, sn2%sd2);
+	}
+
+	/* int32 */
+	var ln1 int32 = +5;
+	var ln2 int32 = -5;
+	var ld1 int32 = +3;
+	var ld2 int32 = -3;
+
+	if ln1/ld1 != q1 || ln1%ld1 != r1 {
+		panicln(ln1, ld1, ln1/ld1, ln1%ld1);
+	}
+	if ln2/ld1 != q2 || ln2%ld1 != r2 {
+		panicln(ln2, ld1, ln2/ld1, ln2%ld1);
+	}
+	if ln1/ld2 != q3 || ln1%ld2 != r3 {
+		panicln(ln1, ld2, ln1/ld2, ln1%ld2);
+	}
+	if ln2/ld2 != q4 || ln2%ld2 != r4 {
+		panicln(ln2, ld2, ln2/ld2, ln2%ld2);
+	}
+
+	/* int64 */
+	var qn1 int64 = +5;
+	var qn2 int64 = -5;
+	var qd1 int64 = +3;
+	var qd2 int64 = -3;
+
+	if qn1/qd1 != q1 || qn1%qd1 != r1 {
+		panicln(qn1, qd1, qn1/qd1, qn1%qd1);
+	}
+	if qn2/qd1 != q2 || qn2%qd1 != r2 {
+		panicln(qn2, qd1, qn2/qd1, qn2%qd1);
+	}
+	if qn1/qd2 != q3 || qn1%qd2 != r3 {
+		panicln(qn1, qd2, qn1/qd2, qn1%qd2);
+	}
+	if qn2/qd2 != q4 || qn2%qd2 != r4 {
+		panicln(qn2, qd2, qn2/qd2, qn2%qd2);
+	}
+
+	/* uint */
+	var uin1 uint = +5;
+	var uid1 uint = +3;
+
+	if uin1/uid1 != q1 || uin1%uid1 != r1 {
+		panicln(uin1, uid1, uin1/uid1, uin1%uid1);
+	}
+
+	/* uint8 */
+	var ubn1 uint8 = +5;
+	var ubd1 uint8 = +3;
+
+	if ubn1/ubd1 != q1 || ubn1%ubd1 != r1 {
+		panicln(ubn1, ubd1, ubn1/ubd1, ubn1%ubd1);
+	}
+
+	/* uint16 */
+	var usn1 uint16 = +5;
+	var usd1 uint16 = +3;
+
+	if usn1/usd1 != q1 || usn1%usd1 != r1 {
+		panicln(usn1, usd1, usn1/usd1, usn1%usd1);
+	}
+
+	/* uint32 */
+	var uln1 uint32 = +5;
+	var uld1 uint32 = +3;
+
+	if uln1/uld1 != q1 || uln1%uld1 != r1 {
+		panicln(uln1, uld1, uln1/uld1, uln1%uld1);
+	}
+
+	/* uint64 */
+	var uqn1 uint64 = +5;
+	var uqd1 uint64 = +3;
+
+	if uqn1/uqd1 != q1 || uqn1%uqd1 != r1 {
+		panicln(uqn1, uqd1, uqn1/uqd1, uqn1%uqd1);
+	}
+	if n1/uqd1 != q1 || n1%uqd1 != r1 {
+		panicln(n1, uqd1, n1/uqd1, n1%uqd1);
+	}
+	if uqn1/d1 != q1 || uqn1%d1 != r1 {
+		panicln(uqn1, d1, uqn1/d1, uqn1%d1);
+	}
+}
-- 
2.48.1