[llvm-commits] [llvm] r75410 - in /llvm/trunk: lib/Support/ConstantRange.cpp unittests/Support/ConstantRangeTest.cpp

[Nick Lewycky]

Author: nicholas
Date: Sat Jul 11 21:19:05 2009
New Revision: 75410

URL: http://llvm.org/viewvc/llvm-project?rev=75410&view=rev
Log:
Implement ConstantRange::multiply based on the code in LoopVR.

Modified:
    llvm/trunk/lib/Support/ConstantRange.cpp
    llvm/trunk/unittests/Support/ConstantRangeTest.cpp

Modified: llvm/trunk/lib/Support/ConstantRange.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Support/ConstantRange.cpp?rev=75410&r1=75409&r2=75410&view=diff

==============================================================================
--- llvm/trunk/lib/Support/ConstantRange.cpp (original)
+++ llvm/trunk/lib/Support/ConstantRange.cpp Sat Jul 11 21:19:05 2009
@@ -550,9 +550,19 @@
 
 ConstantRange
 ConstantRange::multiply(const ConstantRange &Other) const {
-  // TODO: Implement multiply.
-  return ConstantRange(getBitWidth(),
-                       !(isEmptySet() || Other.isEmptySet()));
+  if (isEmptySet() || Other.isEmptySet())
+    return ConstantRange(getBitWidth(), /*isFullSet=*/false);
+  if (isFullSet() || Other.isFullSet())
+    return ConstantRange(getBitWidth(), /*isFullSet=*/true);
+
+  ConstantRange this_zext = zeroExtend(getBitWidth() * 2);
+  ConstantRange Other_zext = Other.zeroExtend(getBitWidth() * 2);
+
+  ConstantRange Result_zext = ConstantRange(
+      this_zext.getLower() * Other_zext.getLower(),
+      ((this_zext.getUpper()-1) * (Other_zext.getUpper()-1)) + 1);
+
+  return Result_zext.truncate(getBitWidth());
 }
 
 ConstantRange

Modified: llvm/trunk/unittests/Support/ConstantRangeTest.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/unittests/Support/ConstantRangeTest.cpp?rev=75410&r1=75409&r2=75410&view=diff

==============================================================================
--- llvm/trunk/unittests/Support/ConstantRangeTest.cpp (original)
+++ llvm/trunk/unittests/Support/ConstantRangeTest.cpp Sat Jul 11 21:19:05 2009
@@ -267,17 +267,13 @@
   EXPECT_EQ(Empty.multiply(One), Empty);
   EXPECT_EQ(Empty.multiply(Some), Empty);
   EXPECT_EQ(Empty.multiply(Wrap), Empty);
-  // TODO: ConstantRange is currently over-conservative here.
-  EXPECT_EQ(One.multiply(One), Full);
-  // TODO: ConstantRange is currently over-conservative here.
-  EXPECT_EQ(One.multiply(Some), Full);
-  // TODO: ConstantRange is currently over-conservative here.
-  EXPECT_EQ(One.multiply(Wrap), Full);
-  // TODO: ConstantRange is currently over-conservative here.
-  EXPECT_EQ(Some.multiply(Some), Full);
-  // TODO: ConstantRange is currently over-conservative here.
+  EXPECT_EQ(One.multiply(One), ConstantRange(APInt(16, 0xa*0xa),
+                                             APInt(16, 0xa*0xa + 1)));
+  EXPECT_EQ(One.multiply(Some), ConstantRange(APInt(16, 0xa*0xa),
+                                              APInt(16, 0xa*0xaa9 + 1)));
+  EXPECT_TRUE(One.multiply(Wrap).isFullSet());
+  EXPECT_TRUE(Some.multiply(Some).isFullSet());
   EXPECT_EQ(Some.multiply(Wrap), Full);
-  // TODO: ConstantRange is currently over-conservative here.
   EXPECT_EQ(Wrap.multiply(Wrap), Full);
 }