diff --git a/llvm/docs/LangRef.rst b/llvm/docs/LangRef.rst
--- a/llvm/docs/LangRef.rst
+++ b/llvm/docs/LangRef.rst
@@ -17180,6 +17180,49 @@
 would and handles error conditions in the same way.
 
 
+Floating Point Environment Manipulation intrinsics
+--------------------------------------------------
+
+These functions read or write floating point environment, such as rounding
+mode or state of floating point exceptions. 
+
+'``llvm.set.rounding``' Intrinsic
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Syntax:
+"""""""
+
+::
+
+      declare void @llvm.set.rounding(i32 <val>)
+
+Overview:
+"""""""""
+
+The '``llvm.set.rounding``' intrinsic sets current rounding mode.
+
+Arguments:
+""""""""""
+
+The argument is the required rounding mode. Encoding of rounding mode is
+compatible with the values returned by ``FLT_ROUNDS``:
+
+::
+
+    0  - toward zero
+    1  - to nearest, ties to even
+    2  - toward positive infinity
+    3  - toward negative infinity
+    4  - to nearest, ties away from zero
+
+Semantics:
+""""""""""
+
+The '``llvm.set.rounding``' intrinsic sets the current rounding mode. It is
+similar to C library function 'fesetround', however this intrinsic does not
+return any value and uses platform-independent representation of rounding modes.
+
+
 General Intrinsics
 ------------------
 
diff --git a/llvm/include/llvm/CodeGen/ISDOpcodes.h b/llvm/include/llvm/CodeGen/ISDOpcodes.h
--- a/llvm/include/llvm/CodeGen/ISDOpcodes.h
+++ b/llvm/include/llvm/CodeGen/ISDOpcodes.h
@@ -666,6 +666,12 @@
     /// FSINCOS - Compute both fsin and fcos as a single operation.
     FSINCOS,
 
+    /// Set rounding mode.
+    /// The first operand is a chain pointer. The second specifies the required
+    /// rounding mode, encoded in the same way as in the intrinsic
+    /// 'set_rounding'.
+    SET_ROUNDING,
+
     /// LOAD and STORE have token chains as their first operand, then the same
     /// operands as an LLVM load/store instruction, then an offset node that
     /// is added / subtracted from the base pointer to form the address (for
diff --git a/llvm/include/llvm/IR/IRBuilder.h b/llvm/include/llvm/IR/IRBuilder.h
--- a/llvm/include/llvm/IR/IRBuilder.h
+++ b/llvm/include/llvm/IR/IRBuilder.h
@@ -913,6 +913,11 @@
     return CreateBinaryIntrinsic(Intrinsic::maximum, LHS, RHS, nullptr, Name);
   }
 
+  /// Create call to the set_rounding intrinsic.
+  CallInst *CreateSetRounding(Value *RM, const Twine &Name = "") {
+    return CreateIntrinsic(Intrinsic::set_rounding, {}, { RM }, nullptr, Name);
+  }
+
 private:
   /// Create a call to a masked intrinsic with given Id.
   CallInst *CreateMaskedIntrinsic(Intrinsic::ID Id, ArrayRef<Value *> Ops,
diff --git a/llvm/include/llvm/IR/Intrinsics.h b/llvm/include/llvm/IR/Intrinsics.h
--- a/llvm/include/llvm/IR/Intrinsics.h
+++ b/llvm/include/llvm/IR/Intrinsics.h
@@ -29,6 +29,17 @@
 class Module;
 class AttributeList;
 
+/// Rounding mode encoding used by 'set_rounding'.
+/// These values must agree with values reported by FLT_ROUNDS.
+enum RoundingMode {
+  TowardZero          = 0,
+  ToNearestTiesToEven = 1,
+  Upward              = 2,
+  Downward            = 3,
+  ToNearestTiesToAway = 4,
+  Indeterminable      = -1
+};
+
 /// This namespace contains an enum with a value for every intrinsic/builtin
 /// function known by LLVM. The enum values are returned by
 /// Function::getIntrinsicID().
diff --git a/llvm/include/llvm/IR/Intrinsics.td b/llvm/include/llvm/IR/Intrinsics.td
--- a/llvm/include/llvm/IR/Intrinsics.td
+++ b/llvm/include/llvm/IR/Intrinsics.td
@@ -603,6 +603,10 @@
                                [IntrNoMem, IntrSpeculatable, IntrWillReturn, ImmArg<1>, ImmArg<2>, ImmArg<3>]>,
                                GCCBuiltin<"__builtin_object_size">;
 
+def int_set_rounding : Intrinsic<[],
+                                 [llvm_i32_ty],
+                                 [IntrInaccessibleMemOnly, IntrWillReturn]>;
+
 //===--------------- Constrained Floating Point Intrinsics ----------------===//
 //
 
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -6289,6 +6289,12 @@
                              DAG.getNode(ISD::BITCAST, sdl, MVT::f16,
                                          getValue(I.getArgOperand(0)))));
     return;
+  case Intrinsic::set_rounding:
+    Res = DAG.getNode(ISD::SET_ROUNDING, sdl, MVT::Other,
+                      { DAG.getRoot(), getValue(I.getArgOperand(0)) });
+    setValue(&I, Res);
+    DAG.setRoot(Res.getValue(0));
+    return;
   case Intrinsic::pcmarker: {
     SDValue Tmp = getValue(I.getArgOperand(0));
     DAG.setRoot(DAG.getNode(ISD::PCMARKER, sdl, MVT::Other, getRoot(), Tmp));
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGDumper.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGDumper.cpp
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGDumper.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGDumper.cpp
@@ -391,6 +391,9 @@
   case ISD::GC_TRANSITION_END:          return "gc_transition.end";
   case ISD::GET_DYNAMIC_AREA_OFFSET:    return "get.dynamic.area.offset";
 
+  // Floating point environment manipulation
+  case ISD::SET_ROUNDING:               return "set_rounding";
+
   // Bit manipulation
   case ISD::ABS:                        return "abs";
   case ISD::BITREVERSE:                 return "bitreverse";
diff --git a/llvm/unittests/IR/IRBuilderTest.cpp b/llvm/unittests/IR/IRBuilderTest.cpp
--- a/llvm/unittests/IR/IRBuilderTest.cpp
+++ b/llvm/unittests/IR/IRBuilderTest.cpp
@@ -121,6 +121,10 @@
   EXPECT_EQ(II->getIntrinsicID(), Intrinsic::fma);
   EXPECT_TRUE(II->hasNoInfs());
   EXPECT_FALSE(II->hasNoNaNs());
+
+  Call = Builder.CreateSetRounding(Builder.getInt32(RoundingMode::TowardZero));
+  II = cast<IntrinsicInst>(Call);
+  EXPECT_EQ(II->getIntrinsicID(), Intrinsic::set_rounding);
 }
 
 TEST_F(IRBuilderTest, IntrinsicsWithScalableVectors) {