[llvm-commits] [llvm] r157231 - in /llvm/trunk: include/llvm/ADT/APInt.h unittests/ADT/APIntTest.cpp

[Nuno Lopes]

Author: nlopes
Date: Mon May 21 20:09:48 2012
New Revision: 157231

URL: http://llvm.org/viewvc/llvm-project?rev=157231&view=rev
Log:
fix the quotient returned by sdivrem() for the case when LHS is negative and RHS is positive
based on a patch by Preston Briggs, with some modifications

Modified:
    llvm/trunk/include/llvm/ADT/APInt.h
    llvm/trunk/unittests/ADT/APIntTest.cpp

Modified: llvm/trunk/include/llvm/ADT/APInt.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/ADT/APInt.h?rev=157231&r1=157230&r2=157231&view=diff
==============================================================================
--- llvm/trunk/include/llvm/ADT/APInt.h (original)
+++ llvm/trunk/include/llvm/ADT/APInt.h Mon May 21 20:09:48 2012
@@ -817,9 +817,10 @@
     if (LHS.isNegative()) {
       if (RHS.isNegative())
         APInt::udivrem(-LHS, -RHS, Quotient, Remainder);
-      else
+      else {
         APInt::udivrem(-LHS, RHS, Quotient, Remainder);
-      Quotient = -Quotient;
+        Quotient = -Quotient;
+      }
       Remainder = -Remainder;
     } else if (RHS.isNegative()) {
       APInt::udivrem(LHS, -RHS, Quotient, Remainder);

Modified: llvm/trunk/unittests/ADT/APIntTest.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/unittests/ADT/APIntTest.cpp?rev=157231&r1=157230&r2=157231&view=diff
==============================================================================
--- llvm/trunk/unittests/ADT/APIntTest.cpp (original)
+++ llvm/trunk/unittests/ADT/APIntTest.cpp Mon May 21 20:09:48 2012
@@ -171,6 +171,34 @@
   EXPECT_EQ(zero, neg_one.srem(one));
   EXPECT_EQ(zero, neg_one.urem(one));
   EXPECT_EQ(zero, one.srem(neg_one));
+
+  // sdivrem
+  {
+  APInt q(8, 0);
+  APInt r(8, 0);
+  APInt one(8, 1);
+  APInt two(8, 2);
+  APInt nine(8, 9);
+  APInt four(8, 4);
+
+  EXPECT_EQ(nine.srem(two), one);
+  EXPECT_EQ(nine.srem(-two), one);
+  EXPECT_EQ((-nine).srem(two), -one);
+  EXPECT_EQ((-nine).srem(-two), -one);
+
+  APInt::sdivrem(nine, two, q, r);
+  EXPECT_EQ(four, q);
+  EXPECT_EQ(one, r);
+  APInt::sdivrem(-nine, two, q, r);
+  EXPECT_EQ(-four, q);
+  EXPECT_EQ(-one, r);
+  APInt::sdivrem(nine, -two, q, r);
+  EXPECT_EQ(-four, q);
+  EXPECT_EQ(one, r);
+  APInt::sdivrem(-nine, -two, q, r);
+  EXPECT_EQ(four, q);
+  EXPECT_EQ(-one, r);
+  }
 }
 
 TEST(APIntTest, fromString) {