Added unit tests to check supported rounding modes

[sepavloff]

Summary

Also added fixed misspelled metadata name.

[kpn]

LGTM

llvm/lib/IR/IntrinsicInst.cpp

case ConstrainedFPIntrinsic::rmToNearest:
     break;
   case ConstrainedFPIntrinsic::rmDownward:
     RoundingStr = "round.downward";
     break;
   case ConstrainedFPIntrinsic::rmUpward:
     RoundingStr = "round.upward";
     break;
   case ConstrainedFPIntrinsic::rmTowardZero:
-    RoundingStr = "round.tozero";
+    RoundingStr = "round.towardzero";
     break;
   }
   return RoundingStr;
 }
 
 Optional<ConstrainedFPIntrinsic::ExceptionBehavior>
 ConstrainedFPIntrinsic::getExceptionBehavior() const {
   unsigned NumOperands = getNumArgOperands();

llvm/unittests/IR/IRBuilderTest.cpp

TEST_F(IRBuilderTest, ConstrainedFP) {
 
   Builder.setDefaultConstrainedExcept(ConstrainedFPIntrinsic::ebIgnore);
   Builder.setDefaultConstrainedRounding(ConstrainedFPIntrinsic::rmUpward);
   V = Builder.CreateFAdd(V, V);
   CII = cast<ConstrainedFPIntrinsic>(V);
   ASSERT_TRUE(CII->getExceptionBehavior() == ConstrainedFPIntrinsic::ebIgnore);
   ASSERT_TRUE(CII->getRoundingMode() == ConstrainedFPIntrinsic::rmUpward);
 
+  Builder.setDefaultConstrainedExcept(ConstrainedFPIntrinsic::ebIgnore);
+  Builder.setDefaultConstrainedRounding(ConstrainedFPIntrinsic::rmToNearest);
+  V = Builder.CreateFAdd(V, V);
+  CII = cast<ConstrainedFPIntrinsic>(V);
+  ASSERT_TRUE(CII->getExceptionBehavior() == ConstrainedFPIntrinsic::ebIgnore);
+  ASSERT_TRUE(CII->getRoundingMode() == ConstrainedFPIntrinsic::rmToNearest);
+
+  Builder.setDefaultConstrainedExcept(ConstrainedFPIntrinsic::ebMayTrap);
+  Builder.setDefaultConstrainedRounding(ConstrainedFPIntrinsic::rmDownward);
+  V = Builder.CreateFAdd(V, V);
+  CII = cast<ConstrainedFPIntrinsic>(V);
+  ASSERT_TRUE(CII->getExceptionBehavior() == ConstrainedFPIntrinsic::ebMayTrap);
+  ASSERT_TRUE(CII->getRoundingMode() == ConstrainedFPIntrinsic::rmDownward);
+
+  Builder.setDefaultConstrainedExcept(ConstrainedFPIntrinsic::ebStrict);
+  Builder.setDefaultConstrainedRounding(ConstrainedFPIntrinsic::rmTowardZero);
+  V = Builder.CreateFAdd(V, V);
+  CII = cast<ConstrainedFPIntrinsic>(V);
+  ASSERT_TRUE(CII->getExceptionBehavior() == ConstrainedFPIntrinsic::ebStrict);
+  ASSERT_TRUE(CII->getRoundingMode() == ConstrainedFPIntrinsic::rmTowardZero);
+
+  Builder.setDefaultConstrainedExcept(ConstrainedFPIntrinsic::ebIgnore);
+  Builder.setDefaultConstrainedRounding(ConstrainedFPIntrinsic::rmDynamic);
+  V = Builder.CreateFAdd(V, V);
+  CII = cast<ConstrainedFPIntrinsic>(V);
+  ASSERT_TRUE(CII->getExceptionBehavior() == ConstrainedFPIntrinsic::ebIgnore);
+  ASSERT_TRUE(CII->getRoundingMode() == ConstrainedFPIntrinsic::rmDynamic);
+
   // Now override the defaults.
   Call = Builder.CreateConstrainedFPBinOp(
         Intrinsic::experimental_constrained_fadd, V, V, nullptr, "", nullptr,
         ConstrainedFPIntrinsic::rmDownward, ConstrainedFPIntrinsic::ebMayTrap);
   CII = cast<ConstrainedFPIntrinsic>(Call);
   EXPECT_EQ(CII->getIntrinsicID(), Intrinsic::experimental_constrained_fadd);
   ASSERT_TRUE(CII->getExceptionBehavior() == ConstrainedFPIntrinsic::ebMayTrap);
   ASSERT_TRUE(CII->getRoundingMode() == ConstrainedFPIntrinsic::rmDownward);