From 68fcccdb2cfa005b32af15d8539589361773c93f Mon Sep 17 00:00:00 2001
From: xiaojian cai <mc02cxj@gmail.com>
Date: Fri, 3 Nov 2017 21:43:18 +0800
Subject: [PATCH]  types: fix doDivMod algorithm (#4995)

---
 util/types/mydecimal.go      | 2 +-
 util/types/mydecimal_test.go | 4 ++++
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/util/types/mydecimal.go b/util/types/mydecimal.go
index 05dcbe2632..c3c6b99ef9 100644
--- a/util/types/mydecimal.go
+++ b/util/types/mydecimal.go
@@ -1966,7 +1966,7 @@ func doDivMod(from1, from2, to, mod *MyDecimal, fracIncr int) error {
 	start1 := 0
 	stop1 := len1
 	start2 := idx2
-	stop2 := digitsToWords(idx2+prec2) - 1
+	stop2 := idx2 + digitsToWords(prec2) - 1
 
 	/* removing end zeroes */
 	for from2.wordBuf[stop2] == 0 && stop2 >= start2 {
diff --git a/util/types/mydecimal_test.go b/util/types/mydecimal_test.go
index 90081455f4..b6df64cf60 100644
--- a/util/types/mydecimal_test.go
+++ b/util/types/mydecimal_test.go
@@ -653,6 +653,7 @@ func (s *testMyDecimalSuite) TestDivMod(c *C) {
 		{"0.0123456789012345678912345", "9999999999", "0.000000000001234567890246913578148141", nil},
 		{"10.333000000", "12.34500", "0.837019036046982584042122316", nil},
 		{"10.000000000060", "2", "5.000000000030000000", nil},
+		{"51", "0.003430", "14868.804664723032069970", nil},
 	}
 	for _, tt := range tests {
 		var a, b, to MyDecimal
@@ -673,6 +674,7 @@ func (s *testMyDecimalSuite) TestDivMod(c *C) {
 		{"-234.567", "10.555", "-2.357", nil},
 		{"234.567", "-10.555", "2.357", nil},
 		{"99999999999999999999999999999999999999", "3", "0", nil},
+		{"51", "0.003430", "0.002760", nil},
 	}
 	for _, tt := range tests {
 		var a, b, to MyDecimal
@@ -692,6 +694,7 @@ func (s *testMyDecimalSuite) TestDivMod(c *C) {
 		{"1.00", "1", "1.000000", nil},
 		{"1", "1.000", "1.0000", nil},
 		{"2", "3", "0.6667", nil},
+		{"51", "0.003430", "14868.8047", nil},
 	}
 	for _, tt := range tests {
 		var a, b, to MyDecimal
@@ -709,6 +712,7 @@ func (s *testMyDecimalSuite) TestDivMod(c *C) {
 		{"1", "2.0", "1.0", nil},
 		{"1.0", "2", "1.0", nil},
 		{"2.23", "3", "2.23", nil},
+		{"51", "0.003430", "0.002760", nil},
 	}
 	for _, tt := range tests {
 		var a, b, to MyDecimal