big: fix carry error, add test case.

crypto/x509: reenable tests.

R=gri
CC=go-dev
http://go/go-review/1026004

diff --git a/src/pkg/big/arith.go b/src/pkg/big/arith.go
index 2b89638a5d578e7575b71eff8e42d6f0dce47587..d442e1dda3e6ec714f7820973b7cc71546df5646 100644 (file)
--- a/src/pkg/big/arith.go
+++ b/src/pkg/big/arith.go
@@ -82,9 +82,6 @@ func mulWW_g(x, y Word) (z1, z0 Word) {
                // z = z[1]*_B + z[0] = x*y
                z0 = t1<<_W2 + t0;
                z1 = (t1 + t0>>_W2)>>_W2;
-               if z0 < t0 {
-                       z1++;
-               }
                return;
        }
 

diff --git a/src/pkg/big/arith_test.go b/src/pkg/big/arith_test.go
index f47f004efa326732c5e009ed863a2174133155c7..030b81f1689bf9370b194061171ca8f62914f525 100644 (file)
--- a/src/pkg/big/arith_test.go
+++ b/src/pkg/big/arith_test.go
@@ -278,10 +278,11 @@ type mulWWTest struct {
 
 var mulWWTests = []mulWWTest{
        mulWWTest{_M, _M, _M-1, 1},
+       // 32 bit only: mulWWTest{0xc47dfa8c, 50911, 0x98a4, 0x998587f4},
 }
 
 
-func TestMulWWW(t *testing.T) {
+func TestMulWW(t *testing.T) {
        for i, test := range mulWWTests {
                q, r := mulWW_g(test.x, test.y);
                if q != test.q || r != test.r {

diff --git a/src/pkg/big/int_test.go b/src/pkg/big/int_test.go
index 3b110ca86ae765cd148ac9fb0f5b6e2be1cfc105..442b76fcc0e943dab110ed199a4321d79fcab4bc 100644 (file)
--- a/src/pkg/big/int_test.go
+++ b/src/pkg/big/int_test.go
@@ -263,11 +263,40 @@ func checkDiv(x, y []byte) bool {
 }
 
 
+type divTest struct {
+       x, y string;
+       q, r string;
+}
+
+
+var divTests = []divTest{
+       divTest{
+               "476217953993950760840509444250624797097991362735329973741718102894495832294430498335824897858659711275234906400899559094370964723884706254265559534144986498357",
+               "9353930466774385905609975137998169297361893554149986716853295022578535724979483772383667534691121982974895531435241089241440253066816724367338287092081996",
+               "50911",
+               "1",
+       },
+}
+
+
 func TestDiv(t *testing.T) {
        err := quick.Check(checkDiv, nil);
        if err != nil {
                t.Error(err);
        }
+
+       for i, test := range divTests {
+               x, _ := new(Int).SetString(test.x, 10);
+               y, _ := new(Int).SetString(test.y, 10);
+               expectedQ, _ := new(Int).SetString(test.q, 10);
+               expectedR, _ := new(Int).SetString(test.r, 10);
+
+               q, r := new(Int).Div(x, y);
+
+               if CmpInt(q, expectedQ) != 0 || CmpInt(r, expectedR) != 0 {
+                       t.Errorf("#%d got (%s, %s) want (%s, %s)", i, q, r, expectedQ, expectedR);
+               }
+       }
 }
 
 

diff --git a/src/pkg/crypto/x509/x509_test.go b/src/pkg/crypto/x509/x509_test.go
index da82db1df90ababaddebec0b797a516958817257..4b2a5ec8a2d89d097bde2d9c8f52ddadd4a2e00d 100644 (file)
--- a/src/pkg/crypto/x509/x509_test.go
+++ b/src/pkg/crypto/x509/x509_test.go
@@ -4,17 +4,6 @@
 
 package x509
 
-import "testing"
-
-func TestToKeepGoTestHappy(t *testing.T) {
-}
-
-/*
-
-Div is broken for this key in 32-bit mode.
-
-TODO(agl): reenabled when Div is fixed.
-
 import (
        "big";
        "crypto/rsa";
@@ -61,5 +50,3 @@ var rsaPrivateKey = &rsa.PrivateKey{
        P: bigFromString("98920366548084643601728869055592650835572950932266967461790948584315647051443"),
        Q: bigFromString("94560208308847015747498523884063394671606671904944666360068158221458669711639"),
 }
-
-*/
\ No newline at end of file