[IPSCCP] Add getCompare which returns either true, false, undef or null.

getCompare returns true, false or undef constants if the comparison can
be evaluated, or nullptr if it cannot. This is in line with what
ConstantExpr::getCompare returns. It also allows us to use
ConstantExpr::getCompare for comparing constants.

Reviewers: davide, mssimpso, dberlin, anna

Reviewed By: davide

Differential Revision: https://reviews.llvm.org/D43761

llvm-svn: 326720

1 files changed, 71 insertions, 45 deletions

diff --git a/llvm/unittests/Analysis/ValueLatticeTest.cpp b/llvm/unittests/Analysis/ValueLatticeTest.cpp
index 3e410256414..b3e86c48b55 100644
--- a/llvm/unittests/Analysis/ValueLatticeTest.cpp
+++ b/llvm/unittests/Analysis/ValueLatticeTest.cpp
@@ -76,72 +76,98 @@ TEST_F(ValueLatticeTest, MergeIn) {
   EXPECT_TRUE(LV1.isOverdefined());
 }
 
-TEST_F(ValueLatticeTest, satisfiesPredicateIntegers) {
-  auto I32Ty = IntegerType::get(Context, 32);
+TEST_F(ValueLatticeTest, getCompareIntegers) {
+  auto *I32Ty = IntegerType::get(Context, 32);
+  auto *I1Ty = IntegerType::get(Context, 1);
   auto *C1 = ConstantInt::get(I32Ty, 1);
   auto LV1 = ValueLatticeElement::get(C1);
 
-  // Check satisfiesPredicate for equal integer constants.
-  EXPECT_TRUE(LV1.satisfiesPredicate(CmpInst::ICMP_EQ, LV1));
-  EXPECT_TRUE(LV1.satisfiesPredicate(CmpInst::ICMP_SGE, LV1));
-  EXPECT_TRUE(LV1.satisfiesPredicate(CmpInst::ICMP_SLE, LV1));
-  EXPECT_FALSE(LV1.satisfiesPredicate(CmpInst::ICMP_NE, LV1));
-  EXPECT_FALSE(LV1.satisfiesPredicate(CmpInst::ICMP_SLT, LV1));
-  EXPECT_FALSE(LV1.satisfiesPredicate(CmpInst::ICMP_SGT, LV1));
+  // Check getCompare for equal integer constants.
+  EXPECT_TRUE(LV1.getCompare(CmpInst::ICMP_EQ, I1Ty, LV1)->isOneValue());
+  EXPECT_TRUE(LV1.getCompare(CmpInst::ICMP_SGE, I1Ty, LV1)->isOneValue());
+  EXPECT_TRUE(LV1.getCompare(CmpInst::ICMP_SLE, I1Ty, LV1)->isOneValue());
+  EXPECT_TRUE(LV1.getCompare(CmpInst::ICMP_NE, I1Ty, LV1)->isZeroValue());
+  EXPECT_TRUE(LV1.getCompare(CmpInst::ICMP_SLT, I1Ty, LV1)->isZeroValue());
+  EXPECT_TRUE(LV1.getCompare(CmpInst::ICMP_SGT, I1Ty, LV1)->isZeroValue());
 
   auto LV2 =
       ValueLatticeElement::getRange({APInt(32, 10, true), APInt(32, 20, true)});
-  // Check satisfiesPredicate with distinct integer ranges.
-  EXPECT_TRUE(LV1.satisfiesPredicate(CmpInst::ICMP_SLT, LV2));
-  EXPECT_TRUE(LV1.satisfiesPredicate(CmpInst::ICMP_SLE, LV2));
-  EXPECT_TRUE(LV1.satisfiesPredicate(CmpInst::ICMP_NE, LV2));
-  EXPECT_FALSE(LV1.satisfiesPredicate(CmpInst::ICMP_EQ, LV2));
-  EXPECT_FALSE(LV1.satisfiesPredicate(CmpInst::ICMP_SGE, LV2));
-  EXPECT_FALSE(LV1.satisfiesPredicate(CmpInst::ICMP_SGT, LV2));
+  // Check getCompare with distinct integer ranges.
+  EXPECT_TRUE(LV1.getCompare(CmpInst::ICMP_SLT, I1Ty, LV2)->isOneValue());
+  EXPECT_TRUE(LV1.getCompare(CmpInst::ICMP_SLE, I1Ty, LV2)->isOneValue());
+  EXPECT_TRUE(LV1.getCompare(CmpInst::ICMP_NE, I1Ty, LV2)->isOneValue());
+  EXPECT_TRUE(LV1.getCompare(CmpInst::ICMP_EQ, I1Ty, LV2)->isZeroValue());
+  EXPECT_TRUE(LV1.getCompare(CmpInst::ICMP_SGE, I1Ty, LV2)->isZeroValue());
+  EXPECT_TRUE(LV1.getCompare(CmpInst::ICMP_SGT, I1Ty, LV2)->isZeroValue());
 
   auto LV3 =
       ValueLatticeElement::getRange({APInt(32, 15, true), APInt(32, 19, true)});
-  // Check satisfiesPredicate with a subset integer ranges.
-  EXPECT_FALSE(LV2.satisfiesPredicate(CmpInst::ICMP_SLT, LV3));
-  EXPECT_FALSE(LV2.satisfiesPredicate(CmpInst::ICMP_SLE, LV3));
-  EXPECT_FALSE(LV2.satisfiesPredicate(CmpInst::ICMP_NE, LV3));
-  EXPECT_FALSE(LV2.satisfiesPredicate(CmpInst::ICMP_EQ, LV3));
-  EXPECT_FALSE(LV2.satisfiesPredicate(CmpInst::ICMP_SGE, LV3));
-  EXPECT_FALSE(LV2.satisfiesPredicate(CmpInst::ICMP_SGT, LV3));
+  // Check getCompare with a subset integer ranges.
+  EXPECT_EQ(LV2.getCompare(CmpInst::ICMP_SLT, I1Ty, LV3), nullptr);
+  EXPECT_EQ(LV2.getCompare(CmpInst::ICMP_SLE, I1Ty, LV3), nullptr);
+  EXPECT_EQ(LV2.getCompare(CmpInst::ICMP_NE, I1Ty, LV3), nullptr);
+  EXPECT_EQ(LV2.getCompare(CmpInst::ICMP_EQ, I1Ty, LV3), nullptr);
+  EXPECT_EQ(LV2.getCompare(CmpInst::ICMP_SGE, I1Ty, LV3), nullptr);
+  EXPECT_EQ(LV2.getCompare(CmpInst::ICMP_SGT, I1Ty, LV3), nullptr);
 
   auto LV4 =
       ValueLatticeElement::getRange({APInt(32, 15, true), APInt(32, 25, true)});
-  // Check satisfiesPredicate with overlapping integer ranges.
-  EXPECT_FALSE(LV3.satisfiesPredicate(CmpInst::ICMP_SLT, LV4));
-  EXPECT_FALSE(LV3.satisfiesPredicate(CmpInst::ICMP_SLE, LV4));
-  EXPECT_FALSE(LV3.satisfiesPredicate(CmpInst::ICMP_NE, LV4));
-  EXPECT_FALSE(LV3.satisfiesPredicate(CmpInst::ICMP_EQ, LV4));
-  EXPECT_FALSE(LV3.satisfiesPredicate(CmpInst::ICMP_SGE, LV4));
-  EXPECT_FALSE(LV3.satisfiesPredicate(CmpInst::ICMP_SGT, LV4));
+  // Check getCompare with overlapping integer ranges.
+  EXPECT_EQ(LV3.getCompare(CmpInst::ICMP_SLT, I1Ty, LV4), nullptr);
+  EXPECT_EQ(LV3.getCompare(CmpInst::ICMP_SLE, I1Ty, LV4), nullptr);
+  EXPECT_EQ(LV3.getCompare(CmpInst::ICMP_NE, I1Ty, LV4), nullptr);
+  EXPECT_EQ(LV3.getCompare(CmpInst::ICMP_EQ, I1Ty, LV4), nullptr);
+  EXPECT_EQ(LV3.getCompare(CmpInst::ICMP_SGE, I1Ty, LV4), nullptr);
+  EXPECT_EQ(LV3.getCompare(CmpInst::ICMP_SGT, I1Ty, LV4), nullptr);
 }
 
-TEST_F(ValueLatticeTest, satisfiesPredicateFloat) {
-  auto FloatTy = IntegerType::getFloatTy(Context);
+TEST_F(ValueLatticeTest, getCompareFloat) {
+  auto *FloatTy = IntegerType::getFloatTy(Context);
+  auto *I1Ty = IntegerType::get(Context, 1);
   auto *C1 = ConstantFP::get(FloatTy, 1.0);
   auto LV1 = ValueLatticeElement::get(C1);
   auto LV2 = ValueLatticeElement::get(C1);
 
-  // Check satisfiesPredicate for equal floating point constants.
-  EXPECT_TRUE(LV1.satisfiesPredicate(CmpInst::FCMP_OEQ, LV2));
-  EXPECT_FALSE(LV1.satisfiesPredicate(CmpInst::FCMP_OGE, LV2));
-  EXPECT_FALSE(LV1.satisfiesPredicate(CmpInst::FCMP_OLE, LV2));
-  EXPECT_FALSE(LV1.satisfiesPredicate(CmpInst::FCMP_ONE, LV2));
-  EXPECT_FALSE(LV1.satisfiesPredicate(CmpInst::FCMP_OLT, LV2));
-  EXPECT_FALSE(LV1.satisfiesPredicate(CmpInst::FCMP_OGT, LV2));
+  // Check getCompare for equal floating point constants.
+  EXPECT_TRUE(LV1.getCompare(CmpInst::FCMP_OEQ, I1Ty, LV2)->isOneValue());
+  EXPECT_TRUE(LV1.getCompare(CmpInst::FCMP_OGE, I1Ty, LV2)->isOneValue());
+  EXPECT_TRUE(LV1.getCompare(CmpInst::FCMP_OLE, I1Ty, LV2)->isOneValue());
+  EXPECT_TRUE(LV1.getCompare(CmpInst::FCMP_ONE, I1Ty, LV2)->isZeroValue());
+  EXPECT_TRUE(LV1.getCompare(CmpInst::FCMP_OLT, I1Ty, LV2)->isZeroValue());
+  EXPECT_TRUE(LV1.getCompare(CmpInst::FCMP_OGT, I1Ty, LV2)->isZeroValue());
 
   LV1.mergeIn(ValueLatticeElement::get(ConstantFP::get(FloatTy, 2.2)),
               M.getDataLayout());
-  EXPECT_FALSE(LV1.satisfiesPredicate(CmpInst::FCMP_OEQ, LV2));
-  EXPECT_FALSE(LV1.satisfiesPredicate(CmpInst::FCMP_OGE, LV2));
-  EXPECT_FALSE(LV1.satisfiesPredicate(CmpInst::FCMP_OLE, LV2));
-  EXPECT_FALSE(LV1.satisfiesPredicate(CmpInst::FCMP_ONE, LV2));
-  EXPECT_FALSE(LV1.satisfiesPredicate(CmpInst::FCMP_OLT, LV2));
-  EXPECT_FALSE(LV1.satisfiesPredicate(CmpInst::FCMP_OGT, LV2));
+  EXPECT_EQ(LV1.getCompare(CmpInst::FCMP_OEQ, I1Ty, LV2), nullptr);
+  EXPECT_EQ(LV1.getCompare(CmpInst::FCMP_OGE, I1Ty, LV2), nullptr);
+  EXPECT_EQ(LV1.getCompare(CmpInst::FCMP_OLE, I1Ty, LV2), nullptr);
+  EXPECT_EQ(LV1.getCompare(CmpInst::FCMP_ONE, I1Ty, LV2), nullptr);
+  EXPECT_EQ(LV1.getCompare(CmpInst::FCMP_OLT, I1Ty, LV2), nullptr);
+  EXPECT_EQ(LV1.getCompare(CmpInst::FCMP_OGT, I1Ty, LV2), nullptr);
+}
+
+TEST_F(ValueLatticeTest, getCompareUndef) {
+  auto *I32Ty = IntegerType::get(Context, 32);
+  auto *I1Ty = IntegerType::get(Context, 1);
+
+  auto LV1 = ValueLatticeElement::get(UndefValue::get(I32Ty));
+  auto LV2 =
+      ValueLatticeElement::getRange({APInt(32, 10, true), APInt(32, 20, true)});
+  EXPECT_TRUE(isa<UndefValue>(LV1.getCompare(CmpInst::ICMP_SLT, I1Ty, LV2)));
+  EXPECT_TRUE(isa<UndefValue>(LV1.getCompare(CmpInst::ICMP_SLE, I1Ty, LV2)));
+  EXPECT_TRUE(isa<UndefValue>(LV1.getCompare(CmpInst::ICMP_NE, I1Ty, LV2)));
+  EXPECT_TRUE(isa<UndefValue>(LV1.getCompare(CmpInst::ICMP_EQ, I1Ty, LV2)));
+  EXPECT_TRUE(isa<UndefValue>(LV1.getCompare(CmpInst::ICMP_SGE, I1Ty, LV2)));
+  EXPECT_TRUE(isa<UndefValue>(LV1.getCompare(CmpInst::ICMP_SGT, I1Ty, LV2)));
+
+  auto *FloatTy = IntegerType::getFloatTy(Context);
+  auto LV3 = ValueLatticeElement::get(ConstantFP::get(FloatTy, 1.0));
+  EXPECT_TRUE(isa<UndefValue>(LV1.getCompare(CmpInst::FCMP_OEQ, I1Ty, LV3)));
+  EXPECT_TRUE(isa<UndefValue>(LV1.getCompare(CmpInst::FCMP_OGE, I1Ty, LV3)));
+  EXPECT_TRUE(isa<UndefValue>(LV1.getCompare(CmpInst::FCMP_OLE, I1Ty, LV3)));
+  EXPECT_TRUE(isa<UndefValue>(LV1.getCompare(CmpInst::FCMP_ONE, I1Ty, LV3)));
+  EXPECT_TRUE(isa<UndefValue>(LV1.getCompare(CmpInst::FCMP_OLT, I1Ty, LV3)));
+  EXPECT_TRUE(isa<UndefValue>(LV1.getCompare(CmpInst::FCMP_OGT, I1Ty, LV3)));
 }
 
 } // end anonymous namespace