Reapply "Add support for #pragma float_control" with buildbot fixes

Add support for #pragma float_control

Reviewers: rjmccall, erichkeane, sepavloff

Differential Revision: https://reviews.llvm.org/D72841

This reverts commit fce82c0ed3.

clang/docs/LanguageExtensions.rst

@@ -3197,6 +3197,41 @@ The pragma can also be used with ``off`` which turns FP contraction off for a
 section of the code. This can be useful when fast contraction is otherwise
 enabled for the translation unit with the ``-ffp-contract=fast`` flag.
 
+The ``#pragma float_control`` pragma allows precise floating-point
+semantics and floating-point exception behavior to be specified
+for a section of the source code. This pragma can only appear at file scope or
+at the start of a compound statement (excluding comments). When using within a
+compound statement, the pragma is active within the scope of the compound
+statement.  This pragma is modeled after a Microsoft pragma with the
+same spelling and syntax.  For pragmas specified at file scope, a stack
+is supported so that the ``pragma float_control`` settings can be pushed or popped.
+
+When ``pragma float_control(precise, on)`` is enabled, the section of code
+governed by the pragma uses precise floating point semantics, effectively
+``-ffast-math`` is disabled and ``-ffp-contract=on``
+(fused multiply add) is enabled.
+
+When ``pragma float_control(except, on)`` is enabled, the section of code governed
+by the pragma behaves as though the command-line option
+``-ffp-exception-behavior=strict`` is enabled,
+when ``pragma float_control(precise, off)`` is enabled, the section of code
+governed by the pragma behaves as though the command-line option
+``-ffp-exception-behavior=ignore`` is enabled.
+
+The full syntax this pragma supports is
+``float_control(except|precise, on|off [, push])`` and
+``float_control(push|pop)``.
+The ``push`` and ``pop`` forms, including using ``push`` as the optional
+third argument, can only occur at file scope.
+
+.. code-block:: c++
+
+  for(...) {
+    // This block will be compiled with -fno-fast-math and -ffp-contract=on
+    #pragma float_control(precise, on)
+    a = b[i] * c[i] + e;
+  }
+
 Specifying an attribute for multiple declarations (#pragma clang attribute)
 ===========================================================================
 

clang/include/clang/AST/Expr.h

@@ -2107,26 +2107,48 @@ public:
 ///   applied to a non-complex value, the former returns its operand and the
 ///   later returns zero in the type of the operand.
 ///
-class UnaryOperator : public Expr {
+class UnaryOperator final
+    : public Expr,
+      private llvm::TrailingObjects<UnaryOperator, FPOptions> {
   Stmt *Val;
 
+  size_t numTrailingObjects(OverloadToken<FPOptions>) const {
+    return UnaryOperatorBits.HasFPFeatures ? 1 : 0;
+  }
+
+  FPOptions &getTrailingFPFeatures() {
+    assert(UnaryOperatorBits.HasFPFeatures);
+    return *getTrailingObjects<FPOptions>();
+  }
+
+  const FPOptions &getTrailingFPFeatures() const {
+    assert(UnaryOperatorBits.HasFPFeatures);
+    return *getTrailingObjects<FPOptions>();
+  }
+
 public:
   typedef UnaryOperatorKind Opcode;
 
-  UnaryOperator(Expr *input, Opcode opc, QualType type, ExprValueKind VK,
+protected:
-                ExprObjectKind OK, SourceLocation l, bool CanOverflow)
+  UnaryOperator(const ASTContext &Ctx, Expr *input, Opcode opc, QualType type,
-      : Expr(UnaryOperatorClass, type, VK, OK), Val(input) {
+                ExprValueKind VK, ExprObjectKind OK, SourceLocation l,
-    UnaryOperatorBits.Opc = opc;
+                bool CanOverflow, FPOptions FPFeatures);
-    UnaryOperatorBits.CanOverflow = CanOverflow;
-    UnaryOperatorBits.Loc = l;
-    setDependence(computeDependence(this));
-  }
 
   /// Build an empty unary operator.
-  explicit UnaryOperator(EmptyShell Empty) : Expr(UnaryOperatorClass, Empty) {
+  explicit UnaryOperator(bool HasFPFeatures, EmptyShell Empty)
+      : Expr(UnaryOperatorClass, Empty) {
     UnaryOperatorBits.Opc = UO_AddrOf;
+    UnaryOperatorBits.HasFPFeatures = HasFPFeatures;
   }
 
+public:
+  static UnaryOperator *CreateEmpty(const ASTContext &C, bool hasFPFeatures);
+
+  static UnaryOperator *Create(const ASTContext &C, Expr *input, Opcode opc,
+                               QualType type, ExprValueKind VK,
+                               ExprObjectKind OK, SourceLocation l,
+                               bool CanOverflow, FPOptions FPFeatures);
+
   Opcode getOpcode() const {
     return static_cast<Opcode>(UnaryOperatorBits.Opc);
   }
@@ -2148,6 +2170,18 @@ public:
   bool canOverflow() const { return UnaryOperatorBits.CanOverflow; }
   void setCanOverflow(bool C) { UnaryOperatorBits.CanOverflow = C; }
 
+  // Get the FP contractability status of this operator. Only meaningful for
+  // operations on floating point types.
+  bool isFPContractableWithinStatement(const LangOptions &LO) const {
+    return getFPFeatures(LO).allowFPContractWithinStatement();
+  }
+
+  // Get the FENV_ACCESS status of this operator. Only meaningful for
+  // operations on floating point types.
+  bool isFEnvAccessOn(const LangOptions &LO) const {
+    return getFPFeatures(LO).allowFEnvAccess();
+  }
+
   /// isPostfix - Return true if this is a postfix operation, like x++.
   static bool isPostfix(Opcode Op) {
     return Op == UO_PostInc || Op == UO_PostDec;
@@ -2214,6 +2248,30 @@ public:
   const_child_range children() const {
     return const_child_range(&Val, &Val + 1);
   }
+
+  /// Is FPFeatures in Trailing Storage?
+  bool hasStoredFPFeatures() const { return UnaryOperatorBits.HasFPFeatures; }
+
+protected:
+  /// Get FPFeatures from trailing storage
+  FPOptions getStoredFPFeatures() const { return getTrailingFPFeatures(); }
+
+  /// Set FPFeatures in trailing storage, used only by Serialization
+  void setStoredFPFeatures(FPOptions F) { getTrailingFPFeatures() = F; }
+
+public:
+  // Get the FP features status of this operator. Only meaningful for
+  // operations on floating point types.
+  FPOptions getFPFeatures(const LangOptions &LO) const {
+    if (UnaryOperatorBits.HasFPFeatures)
+      return getStoredFPFeatures();
+    return FPOptions::defaultWithoutTrailingStorage(LO);
+  }
+
+  friend TrailingObjects;
+  friend class ASTReader;
+  friend class ASTStmtReader;
+  friend class ASTStmtWriter;
 };
 
 /// Helper class for OffsetOfExpr.

clang/include/clang/AST/Stmt.h

@@ -427,6 +427,11 @@ protected:
 
     unsigned Opc : 5;
     unsigned CanOverflow : 1;
+    //
+    /// This is only meaningful for operations on floating point
+    /// types when additional values need to be in trailing storage.
+    /// It is 0 otherwise.
+    unsigned HasFPFeatures : 1;
 
     SourceLocation Loc;
   };
@@ -610,7 +615,7 @@ protected:
     unsigned OperatorKind : 6;
 
     // Only meaningful for floating point types.
-    unsigned FPFeatures : 8;
+    unsigned FPFeatures : 14;
   };
 
   class CXXRewrittenBinaryOperatorBitfields {

clang/include/clang/Basic/DiagnosticParseKinds.td

@@ -1097,9 +1097,9 @@ def warn_pragma_init_seg_unsupported_target : Warning<
   "'#pragma init_seg' is only supported when targeting a "
   "Microsoft environment">,
   InGroup<IgnoredPragmas>;
-// - #pragma fp_contract
+// - #pragma restricted to file scope or start of compound statement
-def err_pragma_fp_contract_scope : Error<
+def err_pragma_file_or_compound_scope : Error<
-  "'#pragma fp_contract' can only appear at file scope or at the start of a "
+  "'#pragma %0' can only appear at file scope or at the start of a "
   "compound statement">;
 // - #pragma stdc unknown
 def ext_stdc_pragma_ignored : ExtWarn<"unknown pragma in STDC namespace">,
@@ -1118,6 +1118,10 @@ def warn_pragma_comment_ignored : Warning<"'#pragma comment %0' ignored">,
 def err_pragma_detect_mismatch_malformed : Error<
   "pragma detect_mismatch is malformed; it requires two comma-separated "
   "string literals">;
+// - #pragma float_control
+def err_pragma_float_control_malformed : Error<
+  "pragma float_control is malformed; use 'float_control({push|pop})' or "
+  "'float_control({precise|except}, {on|off} [,push])'">;
 // - #pragma pointers_to_members
 def err_pragma_pointers_to_members_unknown_kind : Error<
   "unexpected %0, expected to see one of %select{|'best_case', 'full_generality', }1"
@@ -1332,9 +1336,6 @@ def err_pragma_fp_invalid_option : Error<
 def err_pragma_fp_invalid_argument : Error<
   "unexpected argument '%0' to '#pragma clang fp %1'; "
   "expected 'on', 'fast' or 'off'">;
-def err_pragma_fp_scope : Error<
-  "'#pragma clang fp' can only appear at file scope or at the start of a "
-  "compound statement">;
 
 def err_pragma_invalid_keyword : Error<
   "invalid argument; expected 'enable'%select{|, 'full'}0%select{|, 'assume_safety'}1 or 'disable'">;

clang/include/clang/Basic/DiagnosticSemaKinds.td

@@ -858,6 +858,16 @@ def warn_pragma_pack_pop_identifier_and_alignment : Warning<
   "specifying both a name and alignment to 'pop' is undefined">;
 def warn_pragma_pop_failed : Warning<"#pragma %0(pop, ...) failed: %1">,
   InGroup<IgnoredPragmas>;
+def err_pragma_fc_pp_scope : Error<
+  "'#pragma float_control push/pop' can only appear at file scope">;
+def err_pragma_fc_noprecise_requires_nofenv : Error<
+  "'#pragma float_control(precise, off)' is illegal when fenv_access is enabled">;
+def err_pragma_fc_except_requires_precise : Error<
+  "'#pragma float_control(except, on)' is illegal when precise is disabled">;
+def err_pragma_fc_noprecise_requires_noexcept : Error<
+  "'#pragma float_control(precise, off)' is illegal when except is enabled">;
+def err_pragma_fenv_requires_precise : Error<
+  "'#pragma STDC FENV_ACCESS ON' is illegal when precise is disabled">;
 def warn_cxx_ms_struct :
   Warning<"ms_struct may not produce Microsoft-compatible layouts for classes "
           "with base classes or virtual functions">,

clang/include/clang/Basic/LangOptions.def

@@ -191,6 +191,12 @@ COMPATIBLE_LANGOPT(Deprecated        , 1, 0, "__DEPRECATED predefined macro")
 COMPATIBLE_LANGOPT(FastMath          , 1, 0, "fast FP math optimizations, and __FAST_MATH__ predefined macro")
 COMPATIBLE_LANGOPT(FiniteMathOnly    , 1, 0, "__FINITE_MATH_ONLY__ predefined macro")
 COMPATIBLE_LANGOPT(UnsafeFPMath      , 1, 0, "Unsafe Floating Point Math")
+COMPATIBLE_LANGOPT(AllowFPReassoc    , 1, 0, "Permit Floating Point reassociation")
+COMPATIBLE_LANGOPT(NoHonorNaNs       , 1, 0, "Permit Floating Point optimization without regard to NaN")
+COMPATIBLE_LANGOPT(NoHonorInfs       , 1, 0, "Permit Floating Point optimization without regard to infinities")
+COMPATIBLE_LANGOPT(NoSignedZero      , 1, 0, "Permit Floating Point optimization without regard to signed zeros")
+COMPATIBLE_LANGOPT(AllowRecip        , 1, 0, "Permit Floating Point reciprocal")
+COMPATIBLE_LANGOPT(ApproxFunc        , 1, 0, "Permit Floating Point approximation")
 
 BENIGN_LANGOPT(ObjCGCBitmapPrint , 1, 0, "printing of GC's bitmap layout for __weak/__strong ivars")
 

clang/include/clang/Basic/LangOptions.h

@@ -377,28 +377,33 @@ class FPOptions {
   using RoundingMode = llvm::RoundingMode;
 
 public:
-  FPOptions() : fp_contract(LangOptions::FPC_Off),
+  FPOptions()
-                fenv_access(LangOptions::FEA_Off),
+      : fp_contract(LangOptions::FPC_Off), fenv_access(LangOptions::FEA_Off),
-                rounding(LangOptions::FPR_ToNearest),
+        rounding(LangOptions::FPR_ToNearest),
-                exceptions(LangOptions::FPE_Ignore)
+        exceptions(LangOptions::FPE_Ignore), allow_reassoc(0), no_nans(0),
-        {}
+        no_infs(0), no_signed_zeros(0), allow_reciprocal(0), approx_func(0) {}
 
   // Used for serializing.
-  explicit FPOptions(unsigned I)
+  explicit FPOptions(unsigned I) { getFromOpaqueInt(I); }
-      : fp_contract(I & 3),
-        fenv_access((I >> 2) & 1),
-        rounding   ((I >> 3) & 7),
-        exceptions ((I >> 6) & 3)
-        {}
 
   explicit FPOptions(const LangOptions &LangOpts)
       : fp_contract(LangOpts.getDefaultFPContractMode()),
         fenv_access(LangOptions::FEA_Off),
-        rounding(LangOptions::FPR_ToNearest),
+        rounding(static_cast<unsigned>(LangOpts.getFPRoundingMode())),
-        exceptions(LangOptions::FPE_Ignore)
+        exceptions(LangOpts.getFPExceptionMode()),
-        {}
+        allow_reassoc(LangOpts.FastMath || LangOpts.AllowFPReassoc),
+        no_nans(LangOpts.FastMath || LangOpts.NoHonorNaNs),
+        no_infs(LangOpts.FastMath || LangOpts.NoHonorInfs),
+        no_signed_zeros(LangOpts.FastMath || LangOpts.NoSignedZero),
+        allow_reciprocal(LangOpts.FastMath || LangOpts.AllowRecip),
+        approx_func(LangOpts.FastMath || LangOpts.ApproxFunc) {}
   // FIXME: Use getDefaultFEnvAccessMode() when available.
 
+  void setFastMath(bool B = true) {
+    allow_reassoc = no_nans = no_infs = no_signed_zeros = approx_func =
+        allow_reciprocal = B;
+  }
+
   /// Return the default value of FPOptions that's used when trailing
   /// storage isn't required.
   static FPOptions defaultWithoutTrailingStorage(const LangOptions &LO);
@@ -433,6 +438,18 @@ public:
     fenv_access = LangOptions::FEA_On;
   }
 
+  void setFPPreciseEnabled(bool Value) {
+    if (Value) {
+      /* Precise mode implies fp_contract=on and disables ffast-math */
+      setFastMath(false);
+      setAllowFPContractWithinStatement();
+    } else {
+      /* Precise mode implies fp_contract=fast and enables ffast-math */
+      setFastMath(true);
+      setAllowFPContractAcrossStatement();
+    }
+  }
+
   void setDisallowFEnvAccess() { fenv_access = LangOptions::FEA_Off; }
 
   RoundingMode getRoundingMode() const {
@@ -451,6 +468,22 @@ public:
     exceptions = EM;
   }
 
+  /// FMF Flag queries
+  bool allowAssociativeMath() const { return allow_reassoc; }
+  bool noHonorNaNs() const { return no_nans; }
+  bool noHonorInfs() const { return no_infs; }
+  bool noSignedZeros() const { return no_signed_zeros; }
+  bool allowReciprocalMath() const { return allow_reciprocal; }
+  bool allowApproximateFunctions() const { return approx_func; }
+
+  /// Flag setters
+  void setAllowAssociativeMath(bool B = true) { allow_reassoc = B; }
+  void setNoHonorNaNs(bool B = true) { no_nans = B; }
+  void setNoHonorInfs(bool B = true) { no_infs = B; }
+  void setNoSignedZeros(bool B = true) { no_signed_zeros = B; }
+  void setAllowReciprocalMath(bool B = true) { allow_reciprocal = B; }
+  void setAllowApproximateFunctions(bool B = true) { approx_func = B; }
+
   bool isFPConstrained() const {
     return getRoundingMode() != RoundingMode::NearestTiesToEven ||
            getExceptionMode() != LangOptions::FPE_Ignore ||
@@ -460,7 +493,23 @@ public:
   /// Used to serialize this.
   unsigned getAsOpaqueInt() const {
     return fp_contract | (fenv_access << 2) | (rounding << 3) |
-           (exceptions << 6);
+           (exceptions << 6) | (allow_reassoc << 8) | (no_nans << 9) |
+           (no_infs << 10) | (no_signed_zeros << 11) |
+           (allow_reciprocal << 12) | (approx_func << 13);
+  }
+
+  /// Used with getAsOpaqueInt() to manage the float_control pragma stack.
+  void getFromOpaqueInt(unsigned I) {
+    fp_contract = (static_cast<LangOptions::FPContractModeKind>(I & 3));
+    fenv_access = (static_cast<LangOptions::FEnvAccessModeKind>((I >> 2) & 1));
+    rounding = static_cast<unsigned>(static_cast<RoundingMode>((I >> 3) & 7));
+    exceptions = (static_cast<LangOptions::FPExceptionModeKind>((I >> 6) & 3));
+    allow_reassoc = ((I >> 8) & 1);
+    no_nans = ((I >> 9) & 1);
+    no_infs = ((I >> 10) & 1);
+    no_signed_zeros = ((I >> 11) & 1);
+    allow_reciprocal = ((I >> 12) & 1);
+    approx_func = ((I >> 13) & 1);
   }
 
 private:
@@ -471,6 +520,25 @@ private:
   unsigned fenv_access : 1;
   unsigned rounding : 3;
   unsigned exceptions : 2;
+  /// Allow reassociation transformations for floating-point instructions.
+  unsigned allow_reassoc : 1;
+  /// No NaNs - Allow optimizations to assume the arguments and result
+  /// are not NaN. If an argument is a nan, or the result would be a nan,
+  /// it produces a :ref:`poison value <poisonvalues>` instead.
+  unsigned no_nans : 1;
+  /// No Infs - Allow optimizations to assume the arguments and result
+  /// are not +/-Inf. If an argument is +/-Inf, or the result would be +/-Inf,
+  /// it produces a :ref:`poison value <poisonvalues>` instead.
+  unsigned no_infs : 1;
+  /// No Signed Zeros - Allow optimizations to treat the sign of a zero
+  /// argument or result as insignificant.
+  unsigned no_signed_zeros : 1;
+  /// Allow Reciprocal - Allow optimizations to use the reciprocal
+  /// of an argument rather than perform division.
+  unsigned allow_reciprocal : 1;
+  /// Approximate functions - Allow substitution of approximate calculations
+  /// for functions (sin, log, sqrt, etc).
+  unsigned approx_func : 1;
 };
 
 /// Describes the kind of translation unit being processed.

clang/include/clang/Basic/PragmaKinds.h

@@ -25,6 +25,15 @@ enum PragmaMSStructKind {
   PMSST_ON   // #pragms ms_struct on
 };
 
+enum PragmaFloatControlKind {
+  PFC_Unknown,
+  PFC_Precise,   // #pragma float_control(precise, [,on])
+  PFC_NoPrecise, // #pragma float_control(precise, off)
+  PFC_Except,    // #pragma float_control(except [,on])
+  PFC_NoExcept,  // #pragma float_control(except, off)
+  PFC_Push,      // #pragma float_control(push)
+  PFC_Pop        // #pragma float_control(pop)
+};
 }
 
 #endif

clang/include/clang/Basic/TokenKinds.def

@@ -809,6 +809,11 @@ PRAGMA_ANNOTATION(pragma_fp_contract)
 // handles them.
 PRAGMA_ANNOTATION(pragma_fenv_access)
 
+// Annotation for #pragma float_control
+// The lexer produces these so that they only take effect when the parser
+// handles them.
+PRAGMA_ANNOTATION(pragma_float_control)
+
 // Annotation for #pragma pointers_to_members...
 // The lexer produces these so that they only take effect when the parser
 // handles them.

clang/include/clang/Parse/Parser.h

@@ -182,6 +182,7 @@ class Parser : public CodeCompletionHandler {
   std::unique_ptr<PragmaHandler> PCSectionHandler;
   std::unique_ptr<PragmaHandler> MSCommentHandler;
   std::unique_ptr<PragmaHandler> MSDetectMismatchHandler;
+  std::unique_ptr<PragmaHandler> FloatControlHandler;
   std::unique_ptr<PragmaHandler> MSPointersToMembers;
   std::unique_ptr<PragmaHandler> MSVtorDisp;
   std::unique_ptr<PragmaHandler> MSInitSeg;
@@ -741,6 +742,10 @@ private:
   /// #pragma STDC FENV_ACCESS...
   void HandlePragmaFEnvAccess();
 
+  /// Handle the annotation token produced for
+  /// #pragma float_control
+  void HandlePragmaFloatControl();
+
   /// \brief Handle the annotation token produced for
   /// #pragma clang fp ...
   void HandlePragmaFP();

clang/include/clang/Sema/Sema.h

@@ -555,6 +555,9 @@ public:
   PragmaStack<StringLiteral *> ConstSegStack;
   PragmaStack<StringLiteral *> CodeSegStack;
 
+  // This stack tracks the current state of Sema.CurFPFeatures.
+  PragmaStack<unsigned> FpPragmaStack;
+
   // RAII object to push / pop sentinel slots for all MS #pragma stacks.
   // Actions should be performed only if we enter / exit a C++ method body.
   class PragmaStackSentinelRAII {
@@ -1350,7 +1353,7 @@ public:
   /// should not be used elsewhere.
   void EmitCurrentDiagnostic(unsigned DiagID);
 
-  /// Records and restores the FPFeatures state on entry/exit of compound
+  /// Records and restores the CurFPFeatures state on entry/exit of compound
   /// statements.
   class FPFeaturesStateRAII {
   public:
@@ -9566,6 +9569,18 @@ public:
   void ActOnPragmaDetectMismatch(SourceLocation Loc, StringRef Name,
                                  StringRef Value);
 
+  /// Are precise floating point semantics currently enabled?
+  bool isPreciseFPEnabled() {
+    return !CurFPFeatures.allowAssociativeMath() &&
+           !CurFPFeatures.noSignedZeros() &&
+           !CurFPFeatures.allowReciprocalMath() &&
+           !CurFPFeatures.allowApproximateFunctions();
+  }
+
+  /// ActOnPragmaFloatControl - Call on well-formed \#pragma float_control
+  void ActOnPragmaFloatControl(SourceLocation Loc, PragmaMsStackAction Action,
+                               PragmaFloatControlKind Value);
+
   /// ActOnPragmaUnused - Called on well-formed '\#pragma unused'.
   void ActOnPragmaUnused(const Token &Identifier,
                          Scope *curScope,
@@ -9606,7 +9621,8 @@ public:
 
   /// ActOnPragmaFenvAccess - Called on well formed
   /// \#pragma STDC FENV_ACCESS
-  void ActOnPragmaFEnvAccess(LangOptions::FEnvAccessModeKind FPC);
+  void ActOnPragmaFEnvAccess(SourceLocation Loc,
+                             LangOptions::FEnvAccessModeKind FPC);
 
   /// Called to set rounding mode for floating point operations.
   void setRoundingMode(llvm::RoundingMode);

clang/include/clang/Serialization/ASTBitCodes.h

@@ -686,6 +686,9 @@ namespace serialization {
 
       /// Record code for the Decls to be checked for deferred diags.
       DECLS_TO_CHECK_FOR_DEFERRED_DIAGS = 64,
+
+      /// Record code for \#pragma float_control options.
+      FLOAT_CONTROL_PRAGMA_OPTIONS = 65,
     };
 
     /// Record types used within a source manager block.

clang/include/clang/Serialization/ASTReader.h

@@ -857,6 +857,18 @@ private:
   int PragmaMSPointersToMembersState = -1;
   SourceLocation PointersToMembersPragmaLocation;
 
+  /// The pragma float_control state.
+  Optional<unsigned> FpPragmaCurrentValue;
+  SourceLocation FpPragmaCurrentLocation;
+  struct FpPragmaStackEntry {
+    unsigned Value;
+    SourceLocation Location;
+    SourceLocation PushLocation;
+    StringRef SlotLabel;
+  };
+  llvm::SmallVector<FpPragmaStackEntry, 2> FpPragmaStack;
+  llvm::SmallVector<std::string, 2> FpPragmaStrings;
+
   /// The pragma pack state.
   Optional<unsigned> PragmaPackCurrentValue;
   SourceLocation PragmaPackCurrentLocation;

clang/include/clang/Serialization/ASTWriter.h

@@ -505,6 +505,7 @@ private:
   void WriteMSStructPragmaOptions(Sema &SemaRef);
   void WriteMSPointersToMembersPragmaOptions(Sema &SemaRef);
   void WritePackPragmaOptions(Sema &SemaRef);
+  void WriteFloatControlPragmaOptions(Sema &SemaRef);
   void WriteModuleFileExtension(Sema &SemaRef,
                                 ModuleFileExtensionWriter &Writer);
 

clang/lib/AST/ASTImporter.cpp

@@ -6660,9 +6660,10 @@ ExpectedStmt ASTNodeImporter::VisitUnaryOperator(UnaryOperator *E) {
   if (Err)
     return std::move(Err);
 
-  return new (Importer.getToContext()) UnaryOperator(
+  return UnaryOperator::Create(
-      ToSubExpr, E->getOpcode(), ToType, E->getValueKind(), E->getObjectKind(),
+      Importer.getToContext(), ToSubExpr, E->getOpcode(), ToType,
-      ToOperatorLoc, E->canOverflow());
+      E->getValueKind(), E->getObjectKind(), ToOperatorLoc, E->canOverflow(),
+      E->getFPFeatures(Importer.getFromContext().getLangOpts()));
 }
 
 ExpectedStmt

clang/lib/AST/Expr.cpp

@@ -1358,7 +1358,8 @@ CallExpr *CallExpr::CreateTemporary(void *Mem, Expr *Fn, QualType Ty,
   assert(!(reinterpret_cast<uintptr_t>(Mem) % alignof(CallExpr)) &&
          "Misaligned memory in CallExpr::CreateTemporary!");
   return new (Mem) CallExpr(CallExprClass, Fn, /*PreArgs=*/{}, /*Args=*/{}, Ty,
-                            VK, RParenLoc, /*MinNumArgs=*/0, UsesADL);
+                            VK, RParenLoc,
+                            /*MinNumArgs=*/0, UsesADL);
 }
 
 CallExpr *CallExpr::CreateEmpty(const ASTContext &Ctx, unsigned NumArgs,
@@ -4445,6 +4446,38 @@ CompoundAssignOperator *CompoundAssignOperator::Create(
                              CompLHSType, CompResultType);
 }
 
+UnaryOperator *UnaryOperator::CreateEmpty(const ASTContext &C,
+                                          bool hasFPFeatures) {
+  void *Mem = C.Allocate(totalSizeToAlloc<FPOptions>(hasFPFeatures),
+                         alignof(UnaryOperator));
+  return new (Mem) UnaryOperator(hasFPFeatures, EmptyShell());
+}
+
+UnaryOperator::UnaryOperator(const ASTContext &Ctx, Expr *input, Opcode opc,
+                             QualType type, ExprValueKind VK, ExprObjectKind OK,
+                             SourceLocation l, bool CanOverflow,
+                             FPOptions FPFeatures)
+    : Expr(UnaryOperatorClass, type, VK, OK), Val(input) {
+  UnaryOperatorBits.Opc = opc;
+  UnaryOperatorBits.CanOverflow = CanOverflow;
+  UnaryOperatorBits.Loc = l;
+  UnaryOperatorBits.HasFPFeatures =
+      FPFeatures.requiresTrailingStorage(Ctx.getLangOpts());
+  setDependence(computeDependence(this));
+}
+
+UnaryOperator *UnaryOperator::Create(const ASTContext &C, Expr *input,
+                                     Opcode opc, QualType type,
+                                     ExprValueKind VK, ExprObjectKind OK,
+                                     SourceLocation l, bool CanOverflow,
+                                     FPOptions FPFeatures) {
+  bool HasFPFeatures = FPFeatures.requiresTrailingStorage(C.getLangOpts());
+  unsigned Size = totalSizeToAlloc<FPOptions>(HasFPFeatures);
+  void *Mem = C.Allocate(Size, alignof(UnaryOperator));
+  return new (Mem)
+      UnaryOperator(C, input, opc, type, VK, OK, l, CanOverflow, FPFeatures);
+}
+
 const OpaqueValueExpr *OpaqueValueExpr::findInCopyConstruct(const Expr *e) {
   if (const ExprWithCleanups *ewc = dyn_cast<ExprWithCleanups>(e))
     e = ewc->getSubExpr();

clang/lib/Analysis/BodyFarm.cpp

@@ -146,9 +146,10 @@ DeclRefExpr *ASTMaker::makeDeclRefExpr(
 }
 
 UnaryOperator *ASTMaker::makeDereference(const Expr *Arg, QualType Ty) {
-  return new (C) UnaryOperator(const_cast<Expr*>(Arg), UO_Deref, Ty,
+  return UnaryOperator::Create(C, const_cast<Expr *>(Arg), UO_Deref, Ty,
                                VK_LValue, OK_Ordinary, SourceLocation(),
-                              /*CanOverflow*/ false);
+                               /*CanOverflow*/ false,
+                               FPOptions(C.getLangOpts()));
 }
 
 ImplicitCastExpr *ASTMaker::makeLvalueToRvalue(const Expr *Arg, QualType Ty) {
@@ -447,15 +448,16 @@ static Stmt *create_call_once(ASTContext &C, const FunctionDecl *D) {
   QualType DerefType = Deref->getType();
 
   // Negation predicate.
-  UnaryOperator *FlagCheck = new (C) UnaryOperator(
+  UnaryOperator *FlagCheck = UnaryOperator::Create(
+      C,
       /* input=*/
       M.makeImplicitCast(M.makeLvalueToRvalue(Deref, DerefType), DerefType,
                          CK_IntegralToBoolean),
-      /* opc=*/ UO_LNot,
+      /* opc=*/UO_LNot,
-      /* QualType=*/ C.IntTy,
+      /* QualType=*/C.IntTy,
-      /* ExprValueKind=*/ VK_RValue,
+      /* ExprValueKind=*/VK_RValue,
-      /* ExprObjectKind=*/ OK_Ordinary, SourceLocation(),
+      /* ExprObjectKind=*/OK_Ordinary, SourceLocation(),
-      /* CanOverflow*/ false);
+      /* CanOverflow*/ false, FPOptions(C.getLangOpts()));
 
   // Create assignment.
   BinaryOperator *FlagAssignment = M.makeAssignment(
@@ -518,9 +520,9 @@ static Stmt *create_dispatch_once(ASTContext &C, const FunctionDecl *D) {
 
   // (2) Create the assignment to the predicate.
   Expr *DoneValue =
-      new (C) UnaryOperator(M.makeIntegerLiteral(0, C.LongTy), UO_Not, C.LongTy,
+      UnaryOperator::Create(C, M.makeIntegerLiteral(0, C.LongTy), UO_Not,
-                            VK_RValue, OK_Ordinary, SourceLocation(),
+                            C.LongTy, VK_RValue, OK_Ordinary, SourceLocation(),
-                            /*CanOverflow*/false);
+                            /*CanOverflow*/ false, FPOptions(C.getLangOpts()));
 
   BinaryOperator *B =
     M.makeAssignment(

clang/lib/CodeGen/CGExprScalar.cpp

@@ -217,7 +217,14 @@ static bool CanElideOverflowCheck(const ASTContext &Ctx, const BinOpInfo &Op) {
 /// Update the FastMathFlags of LLVM IR from the FPOptions in LangOptions.
 static void updateFastMathFlags(llvm::FastMathFlags &FMF,
                                 FPOptions FPFeatures) {
-  FMF.setAllowContract(FPFeatures.allowFPContractAcrossStatement());
+  FMF.setAllowReassoc(FPFeatures.allowAssociativeMath());
+  FMF.setNoNaNs(FPFeatures.noHonorNaNs());
+  FMF.setNoInfs(FPFeatures.noHonorInfs());
+  FMF.setNoSignedZeros(FPFeatures.noSignedZeros());
+  FMF.setAllowReciprocal(FPFeatures.allowReciprocalMath());
+  FMF.setApproxFunc(FPFeatures.allowApproximateFunctions());
+  FMF.setAllowContract(FPFeatures.allowFPContractAcrossStatement() ||
+                       FPFeatures.allowFPContractWithinStatement());
 }
 
 /// Propagate fast-math flags from \p Op to the instruction in \p V.
@@ -230,6 +237,25 @@ static Value *propagateFMFlags(Value *V, const BinOpInfo &Op) {
   return V;
 }
 
+static void setBuilderFlagsFromFPFeatures(CGBuilderTy &Builder,
+                                          CodeGenFunction &CGF,
+                                          FPOptions FPFeatures) {
+  auto NewRoundingBehavior = FPFeatures.getRoundingMode();
+  Builder.setDefaultConstrainedRounding(NewRoundingBehavior);
+  auto NewExceptionBehavior =
+      ToConstrainedExceptMD(FPFeatures.getExceptionMode());
+  Builder.setDefaultConstrainedExcept(NewExceptionBehavior);
+  auto FMF = Builder.getFastMathFlags();
+  updateFastMathFlags(FMF, FPFeatures);
+  Builder.setFastMathFlags(FMF);
+  assert((CGF.CurFuncDecl == nullptr || Builder.getIsFPConstrained() ||
+          isa<CXXConstructorDecl>(CGF.CurFuncDecl) ||
+          isa<CXXDestructorDecl>(CGF.CurFuncDecl) ||
+          (NewExceptionBehavior == llvm::fp::ebIgnore &&
+           NewRoundingBehavior == llvm::RoundingMode::NearestTiesToEven)) &&
+         "FPConstrained should be enabled on entire function");
+}
+
 class ScalarExprEmitter
   : public StmtVisitor<ScalarExprEmitter, Value*> {
   CodeGenFunction &CGF;
@@ -744,6 +770,9 @@ public:
       return EmitOverflowCheckedBinOp(Ops);
 
     if (Ops.LHS->getType()->isFPOrFPVectorTy()) {
+      //  Preserve the old values
+      llvm::IRBuilder<>::FastMathFlagGuard FMFG(Builder);
+      setBuilderFlagsFromFPFeatures(Builder, CGF, Ops.FPFeatures);
       Value *V = Builder.CreateFMul(Ops.LHS, Ops.RHS, "mul");
       return propagateFMFlags(V, Ops);
     }
@@ -2333,13 +2362,14 @@ Value *ScalarExprEmitter::VisitExprWithCleanups(ExprWithCleanups *E) {
 //===----------------------------------------------------------------------===//
 
 static BinOpInfo createBinOpInfoFromIncDec(const UnaryOperator *E,
-                                           llvm::Value *InVal, bool IsInc) {
+                                           llvm::Value *InVal, bool IsInc,
+                                           FPOptions FPFeatures) {
   BinOpInfo BinOp;
   BinOp.LHS = InVal;
   BinOp.RHS = llvm::ConstantInt::get(InVal->getType(), 1, false);
   BinOp.Ty = E->getType();
   BinOp.Opcode = IsInc ? BO_Add : BO_Sub;
-  // FIXME: once UnaryOperator carries FPFeatures, copy it here.
+  BinOp.FPFeatures = FPFeatures;
   BinOp.E = E;
   return BinOp;
 }
@@ -2359,7 +2389,8 @@ llvm::Value *ScalarExprEmitter::EmitIncDecConsiderOverflowBehavior(
   case LangOptions::SOB_Trapping:
     if (!E->canOverflow())
       return Builder.CreateNSWAdd(InVal, Amount, Name);
-    return EmitOverflowCheckedBinOp(createBinOpInfoFromIncDec(E, InVal, IsInc));
+    return EmitOverflowCheckedBinOp(createBinOpInfoFromIncDec(
+        E, InVal, IsInc, E->getFPFeatures(CGF.getLangOpts())));
   }
   llvm_unreachable("Unknown SignedOverflowBehaviorTy");
 }
@@ -2505,8 +2536,8 @@ ScalarExprEmitter::EmitScalarPrePostIncDec(const UnaryOperator *E, LValue LV,
       value = EmitIncDecConsiderOverflowBehavior(E, value, isInc);
     } else if (E->canOverflow() && type->isUnsignedIntegerType() &&
                CGF.SanOpts.has(SanitizerKind::UnsignedIntegerOverflow)) {
-      value =
+      value = EmitOverflowCheckedBinOp(createBinOpInfoFromIncDec(
-          EmitOverflowCheckedBinOp(createBinOpInfoFromIncDec(E, value, isInc));
+          E, value, isInc, E->getFPFeatures(CGF.getLangOpts())));
     } else {
       llvm::Value *amt = llvm::ConstantInt::get(value->getType(), amount, true);
       value = Builder.CreateAdd(value, amt, isInc ? "inc" : "dec");
@@ -2706,7 +2737,7 @@ Value *ScalarExprEmitter::VisitUnaryMinus(const UnaryOperator *E) {
   BinOp.LHS = llvm::Constant::getNullValue(BinOp.RHS->getType());
   BinOp.Ty = E->getType();
   BinOp.Opcode = BO_Sub;
-  // FIXME: once UnaryOperator carries FPFeatures, copy it here.
+  BinOp.FPFeatures = E->getFPFeatures(CGF.getLangOpts());
   BinOp.E = E;
   return EmitSub(BinOp);
 }
@@ -2723,9 +2754,12 @@ Value *ScalarExprEmitter::VisitUnaryLNot(const UnaryOperator *E) {
     Value *Oper = Visit(E->getSubExpr());
     Value *Zero = llvm::Constant::getNullValue(Oper->getType());
     Value *Result;
-    if (Oper->getType()->isFPOrFPVectorTy())
+    if (Oper->getType()->isFPOrFPVectorTy()) {
+      llvm::IRBuilder<>::FastMathFlagGuard FMFG(Builder);
+      setBuilderFlagsFromFPFeatures(Builder, CGF,
+                                    E->getFPFeatures(CGF.getLangOpts()));
       Result = Builder.CreateFCmp(llvm::CmpInst::FCMP_OEQ, Oper, Zero, "cmp");
-    else
+    } else
       Result = Builder.CreateICmp(llvm::CmpInst::ICMP_EQ, Oper, Zero, "cmp");
     return Builder.CreateSExt(Result, ConvertType(E->getType()), "sext");
   }
@@ -3134,7 +3168,10 @@ Value *ScalarExprEmitter::EmitDiv(const BinOpInfo &Ops) {
   }
 
   if (Ops.LHS->getType()->isFPOrFPVectorTy()) {
-    llvm::Value *Val = Builder.CreateFDiv(Ops.LHS, Ops.RHS, "div");
+    llvm::Value *Val;
+    llvm::IRBuilder<>::FastMathFlagGuard FMFG(Builder);
+    setBuilderFlagsFromFPFeatures(Builder, CGF, Ops.FPFeatures);
+    Val = Builder.CreateFDiv(Ops.LHS, Ops.RHS, "div");
     if (CGF.getLangOpts().OpenCL &&
         !CGF.CGM.getCodeGenOpts().CorrectlyRoundedDivSqrt) {
       // OpenCL v1.1 s7.4: minimum accuracy of single precision / is 2.5ulp
@@ -3506,6 +3543,8 @@ Value *ScalarExprEmitter::EmitAdd(const BinOpInfo &op) {
     return EmitOverflowCheckedBinOp(op);
 
   if (op.LHS->getType()->isFPOrFPVectorTy()) {
+    llvm::IRBuilder<>::FastMathFlagGuard FMFG(Builder);
+    setBuilderFlagsFromFPFeatures(Builder, CGF, op.FPFeatures);
     // Try to form an fmuladd.
     if (Value *FMulAdd = tryEmitFMulAdd(op, CGF, Builder))
       return FMulAdd;
@@ -3688,6 +3727,8 @@ Value *ScalarExprEmitter::EmitSub(const BinOpInfo &op) {
       return EmitOverflowCheckedBinOp(op);
 
     if (op.LHS->getType()->isFPOrFPVectorTy()) {
+      llvm::IRBuilder<>::FastMathFlagGuard FMFG(Builder);
+      setBuilderFlagsFromFPFeatures(Builder, CGF, op.FPFeatures);
       // Try to form an fmuladd.
       if (Value *FMulAdd = tryEmitFMulAdd(op, CGF, Builder, true))
         return FMulAdd;
@@ -4014,6 +4055,8 @@ Value *ScalarExprEmitter::EmitCompare(const BinaryOperator *E,
     if (BOInfo.isFixedPointOp()) {
       Result = EmitFixedPointBinOp(BOInfo);
     } else if (LHS->getType()->isFPOrFPVectorTy()) {
+      llvm::IRBuilder<>::FastMathFlagGuard FMFG(Builder);
+      setBuilderFlagsFromFPFeatures(Builder, CGF, BOInfo.FPFeatures);
       if (!IsSignaling)
         Result = Builder.CreateFCmp(FCmpOpc, LHS, RHS, "cmp");
       else
@@ -4166,6 +4209,9 @@ Value *ScalarExprEmitter::VisitBinLAnd(const BinaryOperator *E) {
     Value *RHS = Visit(E->getRHS());
     Value *Zero = llvm::ConstantAggregateZero::get(LHS->getType());
     if (LHS->getType()->isFPOrFPVectorTy()) {
+      llvm::IRBuilder<>::FastMathFlagGuard FMFG(Builder);
+      setBuilderFlagsFromFPFeatures(Builder, CGF,
+                                    E->getFPFeatures(CGF.getLangOpts()));
       LHS = Builder.CreateFCmp(llvm::CmpInst::FCMP_UNE, LHS, Zero, "cmp");
       RHS = Builder.CreateFCmp(llvm::CmpInst::FCMP_UNE, RHS, Zero, "cmp");
     } else {
@@ -4250,6 +4296,9 @@ Value *ScalarExprEmitter::VisitBinLOr(const BinaryOperator *E) {
     Value *RHS = Visit(E->getRHS());
     Value *Zero = llvm::ConstantAggregateZero::get(LHS->getType());
     if (LHS->getType()->isFPOrFPVectorTy()) {
+      llvm::IRBuilder<>::FastMathFlagGuard FMFG(Builder);
+      setBuilderFlagsFromFPFeatures(Builder, CGF,
+                                    E->getFPFeatures(CGF.getLangOpts()));
       LHS = Builder.CreateFCmp(llvm::CmpInst::FCMP_UNE, LHS, Zero, "cmp");
       RHS = Builder.CreateFCmp(llvm::CmpInst::FCMP_UNE, RHS, Zero, "cmp");
     } else {

clang/lib/CodeGen/CGObjC.cpp

@@ -3556,17 +3556,17 @@ CodeGenFunction::GenerateObjCAtomicSetterCopyHelperFunction(
 
   StartFunction(FD, ReturnTy, Fn, FI, args);
 
-  DeclRefExpr DstExpr(getContext(), &DstDecl, false, DestTy, VK_RValue,
+  DeclRefExpr DstExpr(C, &DstDecl, false, DestTy, VK_RValue, SourceLocation());
-                      SourceLocation());
+  UnaryOperator *DST = UnaryOperator::Create(
-  UnaryOperator DST(&DstExpr, UO_Deref, DestTy->getPointeeType(),
+      C, &DstExpr, UO_Deref, DestTy->getPointeeType(), VK_LValue, OK_Ordinary,
-                    VK_LValue, OK_Ordinary, SourceLocation(), false);
+      SourceLocation(), false, FPOptions(C.getLangOpts()));
 
-  DeclRefExpr SrcExpr(getContext(), &SrcDecl, false, SrcTy, VK_RValue,
+  DeclRefExpr SrcExpr(C, &SrcDecl, false, SrcTy, VK_RValue, SourceLocation());
-                      SourceLocation());
+  UnaryOperator *SRC = UnaryOperator::Create(
-  UnaryOperator SRC(&SrcExpr, UO_Deref, SrcTy->getPointeeType(),
+      C, &SrcExpr, UO_Deref, SrcTy->getPointeeType(), VK_LValue, OK_Ordinary,
-                    VK_LValue, OK_Ordinary, SourceLocation(), false);
+      SourceLocation(), false, FPOptions(C.getLangOpts()));
 
-  Expr *Args[2] = { &DST, &SRC };
+  Expr *Args[2] = {DST, SRC};
   CallExpr *CalleeExp = cast<CallExpr>(PID->getSetterCXXAssignment());
   CXXOperatorCallExpr *TheCall = CXXOperatorCallExpr::Create(
       C, OO_Equal, CalleeExp->getCallee(), Args, DestTy->getPointeeType(),
@@ -3642,14 +3642,15 @@ CodeGenFunction::GenerateObjCAtomicGetterCopyHelperFunction(
   DeclRefExpr SrcExpr(getContext(), &SrcDecl, false, SrcTy, VK_RValue,
                       SourceLocation());
 
-  UnaryOperator SRC(&SrcExpr, UO_Deref, SrcTy->getPointeeType(),
+  UnaryOperator *SRC = UnaryOperator::Create(
-                    VK_LValue, OK_Ordinary, SourceLocation(), false);
+      C, &SrcExpr, UO_Deref, SrcTy->getPointeeType(), VK_LValue, OK_Ordinary,
+      SourceLocation(), false, FPOptions(C.getLangOpts()));
 
   CXXConstructExpr *CXXConstExpr =
     cast<CXXConstructExpr>(PID->getGetterCXXConstructor());
 
   SmallVector<Expr*, 4> ConstructorArgs;
-  ConstructorArgs.push_back(&SRC);
+  ConstructorArgs.push_back(SRC);
   ConstructorArgs.append(std::next(CXXConstExpr->arg_begin()),
                          CXXConstExpr->arg_end());
 

clang/lib/CodeGen/CGStmtOpenMP.cpp

@@ -3055,8 +3055,9 @@ void CodeGenFunction::EmitSections(const OMPExecutableDirective &S) {
         C, &IVRefExpr, &UBRefExpr, BO_LE, C.BoolTy, VK_RValue, OK_Ordinary,
         S.getBeginLoc(), FPOptions(C.getLangOpts()));
     // Increment for loop counter.
-    UnaryOperator Inc(&IVRefExpr, UO_PreInc, KmpInt32Ty, VK_RValue, OK_Ordinary,
+    UnaryOperator *Inc = UnaryOperator::Create(
-                      S.getBeginLoc(), true);
+        C, &IVRefExpr, UO_PreInc, KmpInt32Ty, VK_RValue, OK_Ordinary,
+        S.getBeginLoc(), true, FPOptions(C.getLangOpts()));
     auto &&BodyGen = [CapturedStmt, CS, &S, &IV](CodeGenFunction &CGF) {
       // Iterate through all sections and emit a switch construct:
       // switch (IV) {
@@ -3126,7 +3127,7 @@ void CodeGenFunction::EmitSections(const OMPExecutableDirective &S) {
     // IV = LB;
     CGF.EmitStoreOfScalar(CGF.EmitLoadOfScalar(LB, S.getBeginLoc()), IV);
     // while (idx <= UB) { BODY; ++idx; }
-    CGF.EmitOMPInnerLoop(S, /*RequiresCleanup=*/false, Cond, &Inc, BodyGen,
+    CGF.EmitOMPInnerLoop(S, /*RequiresCleanup=*/false, Cond, Inc, BodyGen,
                          [](CodeGenFunction &) {});
     // Tell the runtime we are done.
     auto &&CodeGen = [&S](CodeGenFunction &CGF) {

clang/lib/CodeGen/CodeGenFunction.cpp

@@ -117,8 +117,8 @@ CodeGenFunction::~CodeGenFunction() {
 
 // Map the LangOption for exception behavior into
 // the corresponding enum in the IR.
-static llvm::fp::ExceptionBehavior ToConstrainedExceptMD(
+llvm::fp::ExceptionBehavior
-  LangOptions::FPExceptionModeKind Kind) {
+clang::ToConstrainedExceptMD(LangOptions::FPExceptionModeKind Kind) {
 
   switch (Kind) {
   case LangOptions::FPE_Ignore:  return llvm::fp::ebIgnore;
@@ -133,15 +133,10 @@ void CodeGenFunction::SetFPModel() {
   auto fpExceptionBehavior = ToConstrainedExceptMD(
                                getLangOpts().getFPExceptionMode());
 
-  if (fpExceptionBehavior == llvm::fp::ebIgnore &&
+  Builder.setDefaultConstrainedRounding(RM);
-      RM == llvm::RoundingMode::NearestTiesToEven)
+  Builder.setDefaultConstrainedExcept(fpExceptionBehavior);
-    // Constrained intrinsics are not used.
+  Builder.setIsFPConstrained(fpExceptionBehavior != llvm::fp::ebIgnore ||
-    ;
+                             RM != llvm::RoundingMode::NearestTiesToEven);
-  else {
-    Builder.setIsFPConstrained(true);
-    Builder.setDefaultConstrainedRounding(RM);
-    Builder.setDefaultConstrainedExcept(fpExceptionBehavior);
-  }
 }
 
 CharUnits CodeGenFunction::getNaturalPointeeTypeAlignment(QualType T,
@@ -919,9 +914,11 @@ void CodeGenFunction::StartFunction(GlobalDecl GD, QualType RetTy,
       Fn->addFnAttr(llvm::Attribute::NoRecurse);
   }
 
-  if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D))
+  if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D)) {
+    Builder.setIsFPConstrained(FD->usesFPIntrin());
     if (FD->usesFPIntrin())
       Fn->addFnAttr(llvm::Attribute::StrictFP);
+  }
 
   // If a custom alignment is used, force realigning to this alignment on
   // any main function which certainly will need it.

clang/lib/CodeGen/CodeGenFunction.h

@@ -4575,6 +4575,11 @@ inline llvm::Value *DominatingLLVMValue::restore(CodeGenFunction &CGF,
 }
 
 }  // end namespace CodeGen
+
+// Map the LangOption for floating point exception behavior into
+// the corresponding enum in the IR.
+llvm::fp::ExceptionBehavior
+ToConstrainedExceptMD(LangOptions::FPExceptionModeKind Kind);
 }  // end namespace clang
 
 #endif

clang/lib/Frontend/CompilerInvocation.cpp

@@ -2455,7 +2455,7 @@ static const StringRef GetInputKindName(InputKind IK) {
 
 static void ParseLangArgs(LangOptions &Opts, ArgList &Args, InputKind IK,
                           const TargetOptions &TargetOpts,
-                          PreprocessorOptions &PPOpts,
+                          PreprocessorOptions &PPOpts, CodeGenOptions &CGOpts,
                           DiagnosticsEngine &Diags) {
   // FIXME: Cleanup per-file based stuff.
   LangStandard::Kind LangStd = LangStandard::lang_unspecified;
@@ -3187,6 +3187,15 @@ static void ParseLangArgs(LangOptions &Opts, ArgList &Args, InputKind IK,
   Opts.UnsafeFPMath = Args.hasArg(OPT_menable_unsafe_fp_math) ||
                       Args.hasArg(OPT_cl_unsafe_math_optimizations) ||
                       Args.hasArg(OPT_cl_fast_relaxed_math);
+  Opts.AllowFPReassoc = Opts.FastMath || CGOpts.Reassociate;
+  Opts.NoHonorNaNs =
+      Opts.FastMath || CGOpts.NoNaNsFPMath || Opts.FiniteMathOnly;
+  Opts.NoHonorInfs =
+      Opts.FastMath || CGOpts.NoInfsFPMath || Opts.FiniteMathOnly;
+  Opts.NoSignedZero = Opts.FastMath || CGOpts.NoSignedZeros;
+  Opts.AllowRecip = Opts.FastMath || CGOpts.ReciprocalMath;
+  // Currently there's no clang option to enable this individually
+  Opts.ApproxFunc = Opts.FastMath;
 
   if (Arg *A = Args.getLastArg(OPT_ffp_contract)) {
     StringRef Val = A->getValue();
@@ -3640,7 +3649,7 @@ bool CompilerInvocation::CreateFromArgs(CompilerInvocation &Res,
     // Other LangOpts are only initialized when the input is not AST or LLVM IR.
     // FIXME: Should we really be calling this for an Language::Asm input?
     ParseLangArgs(LangOpts, Args, DashX, Res.getTargetOpts(),
-                  Res.getPreprocessorOpts(), Diags);
+                  Res.getPreprocessorOpts(), Res.getCodeGenOpts(), Diags);
     if (Res.getFrontendOpts().ProgramAction == frontend::RewriteObjC)
       LangOpts.ObjCExceptions = 1;
     if (T.isOSDarwin() && DashX.isPreprocessed()) {

clang/lib/Frontend/Rewrite/RewriteModernObjC.cpp

@@ -2587,9 +2587,10 @@ Stmt *RewriteModernObjC::RewriteObjCStringLiteral(ObjCStringLiteral *Exp) {
                                    strType, nullptr, SC_Static);
   DeclRefExpr *DRE = new (Context)
       DeclRefExpr(*Context, NewVD, false, strType, VK_LValue, SourceLocation());
-  Expr *Unop = new (Context)
+  Expr *Unop = UnaryOperator::Create(
-      UnaryOperator(DRE, UO_AddrOf, Context->getPointerType(DRE->getType()),
+      const_cast<ASTContext &>(*Context), DRE, UO_AddrOf,
-                    VK_RValue, OK_Ordinary, SourceLocation(), false);
+      Context->getPointerType(DRE->getType()), VK_RValue, OK_Ordinary,
+      SourceLocation(), false, FPOptions(Context->getLangOpts()));
   // cast to NSConstantString *
   CastExpr *cast = NoTypeInfoCStyleCastExpr(Context, Exp->getType(),
                                             CK_CPointerToObjCPointerCast, Unop);
@@ -3283,10 +3284,10 @@ Stmt *RewriteModernObjC::SynthMessageExpr(ObjCMessageExpr *Exp,
       // we need the cast below. For example:
       // (struct __rw_objc_super *)&__rw_objc_super((id)self, (id)objc_getClass("SUPER"))
       //
-      SuperRep = new (Context) UnaryOperator(SuperRep, UO_AddrOf,
+      SuperRep = UnaryOperator::Create(
-                               Context->getPointerType(SuperRep->getType()),
+          const_cast<ASTContext &>(*Context), SuperRep, UO_AddrOf,
-                                             VK_RValue, OK_Ordinary,
+          Context->getPointerType(SuperRep->getType()), VK_RValue, OK_Ordinary,
-                                             SourceLocation(), false);
+          SourceLocation(), false, FPOptions(Context->getLangOpts()));
       SuperRep = NoTypeInfoCStyleCastExpr(Context,
                                           Context->getPointerType(superType),
                                           CK_BitCast, SuperRep);
@@ -3301,10 +3302,10 @@ Stmt *RewriteModernObjC::SynthMessageExpr(ObjCMessageExpr *Exp,
                                                    superType, VK_LValue,
                                                    ILE, false);
       // struct __rw_objc_super *
-      SuperRep = new (Context) UnaryOperator(SuperRep, UO_AddrOf,
+      SuperRep = UnaryOperator::Create(
-                               Context->getPointerType(SuperRep->getType()),
+          const_cast<ASTContext &>(*Context), SuperRep, UO_AddrOf,
-                                             VK_RValue, OK_Ordinary,
+          Context->getPointerType(SuperRep->getType()), VK_RValue, OK_Ordinary,
-                                             SourceLocation(), false);
+          SourceLocation(), false, FPOptions(Context->getLangOpts()));
     }
     MsgExprs.push_back(SuperRep);
     break;
@@ -3378,10 +3379,10 @@ Stmt *RewriteModernObjC::SynthMessageExpr(ObjCMessageExpr *Exp,
       // we need the cast below. For example:
       // (struct __rw_objc_super *)&__rw_objc_super((id)self, (id)objc_getClass("SUPER"))
       //
-      SuperRep = new (Context) UnaryOperator(SuperRep, UO_AddrOf,
+      SuperRep = UnaryOperator::Create(
-                               Context->getPointerType(SuperRep->getType()),
+          const_cast<ASTContext &>(*Context), SuperRep, UO_AddrOf,
-                               VK_RValue, OK_Ordinary,
+          Context->getPointerType(SuperRep->getType()), VK_RValue, OK_Ordinary,
-                               SourceLocation(), false);
+          SourceLocation(), false, FPOptions(Context->getLangOpts()));
       SuperRep = NoTypeInfoCStyleCastExpr(Context,
                                Context->getPointerType(superType),
                                CK_BitCast, SuperRep);
@@ -4705,9 +4706,10 @@ Stmt *RewriteModernObjC::RewriteLocalVariableExternalStorage(DeclRefExpr *DRE) {
   if (VarDecl *Var = dyn_cast<VarDecl>(VD))
     if (!ImportedLocalExternalDecls.count(Var))
       return DRE;
-  Expr *Exp = new (Context) UnaryOperator(DRE, UO_Deref, DRE->getType(),
+  Expr *Exp = UnaryOperator::Create(const_cast<ASTContext &>(*Context), DRE,
-                                          VK_LValue, OK_Ordinary,
+                                    UO_Deref, DRE->getType(), VK_LValue,
-                                          DRE->getLocation(), false);
+                                    OK_Ordinary, DRE->getLocation(), false,
+                                    FPOptions(Context->getLangOpts()));
   // Need parens to enforce precedence.
   ParenExpr *PE = new (Context) ParenExpr(SourceLocation(), SourceLocation(),
                                           Exp);
@@ -5293,11 +5295,12 @@ Stmt *RewriteModernObjC::SynthBlockInitExpr(BlockExpr *Exp,
   VarDecl *NewVD = VarDecl::Create(
       *Context, TUDecl, SourceLocation(), SourceLocation(),
       &Context->Idents.get(DescData), Context->VoidPtrTy, nullptr, SC_Static);
-  UnaryOperator *DescRefExpr = new (Context) UnaryOperator(
+  UnaryOperator *DescRefExpr = UnaryOperator::Create(
+      const_cast<ASTContext &>(*Context),
       new (Context) DeclRefExpr(*Context, NewVD, false, Context->VoidPtrTy,
                                 VK_LValue, SourceLocation()),
       UO_AddrOf, Context->getPointerType(Context->VoidPtrTy), VK_RValue,
-      OK_Ordinary, SourceLocation(), false);
+      OK_Ordinary, SourceLocation(), false, FPOptions(Context->getLangOpts()));
   InitExprs.push_back(DescRefExpr);
 
   // Add initializers for any closure decl refs.
@@ -5314,9 +5317,10 @@ Stmt *RewriteModernObjC::SynthBlockInitExpr(BlockExpr *Exp,
         if (HasLocalVariableExternalStorage(*I)) {
           QualType QT = (*I)->getType();
           QT = Context->getPointerType(QT);
-          Exp = new (Context) UnaryOperator(Exp, UO_AddrOf, QT, VK_RValue,
+          Exp = UnaryOperator::Create(const_cast<ASTContext &>(*Context), Exp,
-                                            OK_Ordinary, SourceLocation(),
+                                      UO_AddrOf, QT, VK_RValue, OK_Ordinary,
-                                            false);
+                                      SourceLocation(), false,
+                                      FPOptions(Context->getLangOpts()));
         }
       } else if (isTopLevelBlockPointerType((*I)->getType())) {
         FD = SynthBlockInitFunctionDecl((*I)->getName());
@@ -5331,9 +5335,10 @@ Stmt *RewriteModernObjC::SynthBlockInitExpr(BlockExpr *Exp,
         if (HasLocalVariableExternalStorage(*I)) {
           QualType QT = (*I)->getType();
           QT = Context->getPointerType(QT);
-          Exp = new (Context) UnaryOperator(Exp, UO_AddrOf, QT, VK_RValue,
+          Exp = UnaryOperator::Create(const_cast<ASTContext &>(*Context), Exp,
-                                            OK_Ordinary, SourceLocation(),
+                                      UO_AddrOf, QT, VK_RValue, OK_Ordinary,
-                                            false);
+                                      SourceLocation(), false,
+                                      FPOptions(Context->getLangOpts()));
         }
 
       }
@@ -5371,10 +5376,10 @@ Stmt *RewriteModernObjC::SynthBlockInitExpr(BlockExpr *Exp,
       // captured nested byref variable has its address passed. Do not take
       // its address again.
       if (!isNestedCapturedVar)
-          Exp = new (Context) UnaryOperator(Exp, UO_AddrOf,
+        Exp = UnaryOperator::Create(
-                                     Context->getPointerType(Exp->getType()),
+            const_cast<ASTContext &>(*Context), Exp, UO_AddrOf,
-                                     VK_RValue, OK_Ordinary, SourceLocation(),
+            Context->getPointerType(Exp->getType()), VK_RValue, OK_Ordinary,
-                                     false);
+            SourceLocation(), false, FPOptions(Context->getLangOpts()));
       Exp = NoTypeInfoCStyleCastExpr(Context, castT, CK_BitCast, Exp);
       InitExprs.push_back(Exp);
     }
@@ -5398,9 +5403,10 @@ Stmt *RewriteModernObjC::SynthBlockInitExpr(BlockExpr *Exp,
     NewRep = DRE;
   }
 
-  NewRep = new (Context) UnaryOperator(NewRep, UO_AddrOf,
+  NewRep = UnaryOperator::Create(
-                             Context->getPointerType(NewRep->getType()),
+      const_cast<ASTContext &>(*Context), NewRep, UO_AddrOf,
-                             VK_RValue, OK_Ordinary, SourceLocation(), false);
+      Context->getPointerType(NewRep->getType()), VK_RValue, OK_Ordinary,
+      SourceLocation(), false, FPOptions(Context->getLangOpts()));
   NewRep = NoTypeInfoCStyleCastExpr(Context, FType, CK_BitCast,
                                     NewRep);
   // Put Paren around the call.
@@ -7539,10 +7545,10 @@ Stmt *RewriteModernObjC::RewriteObjCIvarRefExpr(ObjCIvarRefExpr *IV) {
                                           CK_BitCast,
                                           PE);
 
-
+      Expr *Exp = UnaryOperator::Create(const_cast<ASTContext &>(*Context),
-      Expr *Exp = new (Context) UnaryOperator(castExpr, UO_Deref, IvarT,
+                                        castExpr, UO_Deref, IvarT, VK_LValue,
-                                              VK_LValue, OK_Ordinary,
+                                        OK_Ordinary, SourceLocation(), false,
-                                              SourceLocation(), false);
+                                        FPOptions(Context->getLangOpts()));
       PE = new (Context) ParenExpr(OldRange.getBegin(),
                                    OldRange.getEnd(),
                                    Exp);

clang/lib/Frontend/Rewrite/RewriteObjC.cpp

@@ -2514,9 +2514,10 @@ Stmt *RewriteObjC::RewriteObjCStringLiteral(ObjCStringLiteral *Exp) {
                                    strType, nullptr, SC_Static);
   DeclRefExpr *DRE = new (Context)
       DeclRefExpr(*Context, NewVD, false, strType, VK_LValue, SourceLocation());
-  Expr *Unop = new (Context)
+  Expr *Unop = UnaryOperator::Create(
-      UnaryOperator(DRE, UO_AddrOf, Context->getPointerType(DRE->getType()),
+      const_cast<ASTContext &>(*Context), DRE, UO_AddrOf,
-                    VK_RValue, OK_Ordinary, SourceLocation(), false);
+      Context->getPointerType(DRE->getType()), VK_RValue, OK_Ordinary,
+      SourceLocation(), false, FPOptions(Context->getLangOpts()));
   // cast to NSConstantString *
   CastExpr *cast = NoTypeInfoCStyleCastExpr(Context, Exp->getType(),
                                             CK_CPointerToObjCPointerCast, Unop);
@@ -2714,10 +2715,10 @@ Stmt *RewriteObjC::SynthMessageExpr(ObjCMessageExpr *Exp,
       // we need the cast below. For example:
       // (struct objc_super *)&__rw_objc_super((id)self, (id)objc_getClass("SUPER"))
       //
-      SuperRep = new (Context) UnaryOperator(SuperRep, UO_AddrOf,
+      SuperRep = UnaryOperator::Create(
-                               Context->getPointerType(SuperRep->getType()),
+          const_cast<ASTContext &>(*Context), SuperRep, UO_AddrOf,
-                                             VK_RValue, OK_Ordinary,
+          Context->getPointerType(SuperRep->getType()), VK_RValue, OK_Ordinary,
-                                             SourceLocation(), false);
+          SourceLocation(), false, FPOptions(Context->getLangOpts()));
       SuperRep = NoTypeInfoCStyleCastExpr(Context,
                                           Context->getPointerType(superType),
                                           CK_BitCast, SuperRep);
@@ -2732,10 +2733,10 @@ Stmt *RewriteObjC::SynthMessageExpr(ObjCMessageExpr *Exp,
                                                    superType, VK_LValue,
                                                    ILE, false);
       // struct objc_super *
-      SuperRep = new (Context) UnaryOperator(SuperRep, UO_AddrOf,
+      SuperRep = UnaryOperator::Create(
-                               Context->getPointerType(SuperRep->getType()),
+          const_cast<ASTContext &>(*Context), SuperRep, UO_AddrOf,
-                                             VK_RValue, OK_Ordinary,
+          Context->getPointerType(SuperRep->getType()), VK_RValue, OK_Ordinary,
-                                             SourceLocation(), false);
+          SourceLocation(), false, FPOptions(Context->getLangOpts()));
     }
     MsgExprs.push_back(SuperRep);
     break;
@@ -2809,10 +2810,10 @@ Stmt *RewriteObjC::SynthMessageExpr(ObjCMessageExpr *Exp,
       // we need the cast below. For example:
       // (struct objc_super *)&__rw_objc_super((id)self, (id)objc_getClass("SUPER"))
       //
-      SuperRep = new (Context) UnaryOperator(SuperRep, UO_AddrOf,
+      SuperRep = UnaryOperator::Create(
-                               Context->getPointerType(SuperRep->getType()),
+          const_cast<ASTContext &>(*Context), SuperRep, UO_AddrOf,
-                               VK_RValue, OK_Ordinary,
+          Context->getPointerType(SuperRep->getType()), VK_RValue, OK_Ordinary,
-                               SourceLocation(), false);
+          SourceLocation(), false, FPOptions(Context->getLangOpts()));
       SuperRep = NoTypeInfoCStyleCastExpr(Context,
                                Context->getPointerType(superType),
                                CK_BitCast, SuperRep);
@@ -3048,9 +3049,10 @@ Stmt *RewriteObjC::RewriteObjCProtocolExpr(ObjCProtocolExpr *Exp) {
                                 nullptr, SC_Extern);
   DeclRefExpr *DRE = new (Context) DeclRefExpr(
       *Context, VD, false, getProtocolType(), VK_LValue, SourceLocation());
-  Expr *DerefExpr = new (Context) UnaryOperator(DRE, UO_AddrOf,
+  Expr *DerefExpr = UnaryOperator::Create(
-                             Context->getPointerType(DRE->getType()),
+      const_cast<ASTContext &>(*Context), DRE, UO_AddrOf,
-                             VK_RValue, OK_Ordinary, SourceLocation(), false);
+      Context->getPointerType(DRE->getType()), VK_RValue, OK_Ordinary,
+      SourceLocation(), false, FPOptions(Context->getLangOpts()));
   CastExpr *castExpr = NoTypeInfoCStyleCastExpr(Context, DerefExpr->getType(),
                                                 CK_BitCast,
                                                 DerefExpr);
@@ -3875,9 +3877,10 @@ Stmt *RewriteObjC::RewriteLocalVariableExternalStorage(DeclRefExpr *DRE) {
   if (VarDecl *Var = dyn_cast<VarDecl>(VD))
     if (!ImportedLocalExternalDecls.count(Var))
       return DRE;
-  Expr *Exp = new (Context) UnaryOperator(DRE, UO_Deref, DRE->getType(),
+  Expr *Exp = UnaryOperator::Create(const_cast<ASTContext &>(*Context), DRE,
-                                          VK_LValue, OK_Ordinary,
+                                    UO_Deref, DRE->getType(), VK_LValue,
-                                          DRE->getLocation(), false);
+                                    OK_Ordinary, DRE->getLocation(), false,
+                                    FPOptions(Context->getLangOpts()));
   // Need parens to enforce precedence.
   ParenExpr *PE = new (Context) ParenExpr(SourceLocation(), SourceLocation(),
                                           Exp);
@@ -4432,11 +4435,12 @@ Stmt *RewriteObjC::SynthBlockInitExpr(BlockExpr *Exp,
   VarDecl *NewVD = VarDecl::Create(
       *Context, TUDecl, SourceLocation(), SourceLocation(),
       &Context->Idents.get(DescData), Context->VoidPtrTy, nullptr, SC_Static);
-  UnaryOperator *DescRefExpr = new (Context) UnaryOperator(
+  UnaryOperator *DescRefExpr = UnaryOperator::Create(
+      const_cast<ASTContext &>(*Context),
       new (Context) DeclRefExpr(*Context, NewVD, false, Context->VoidPtrTy,
                                 VK_LValue, SourceLocation()),
       UO_AddrOf, Context->getPointerType(Context->VoidPtrTy), VK_RValue,
-      OK_Ordinary, SourceLocation(), false);
+      OK_Ordinary, SourceLocation(), false, FPOptions(Context->getLangOpts()));
   InitExprs.push_back(DescRefExpr);
 
   // Add initializers for any closure decl refs.
@@ -4453,9 +4457,10 @@ Stmt *RewriteObjC::SynthBlockInitExpr(BlockExpr *Exp,
         if (HasLocalVariableExternalStorage(*I)) {
           QualType QT = (*I)->getType();
           QT = Context->getPointerType(QT);
-          Exp = new (Context) UnaryOperator(Exp, UO_AddrOf, QT, VK_RValue,
+          Exp = UnaryOperator::Create(const_cast<ASTContext &>(*Context), Exp,
-                                            OK_Ordinary, SourceLocation(),
+                                      UO_AddrOf, QT, VK_RValue, OK_Ordinary,
-                                            false);
+                                      SourceLocation(), false,
+                                      FPOptions(Context->getLangOpts()));
         }
       } else if (isTopLevelBlockPointerType((*I)->getType())) {
         FD = SynthBlockInitFunctionDecl((*I)->getName());
@@ -4470,9 +4475,10 @@ Stmt *RewriteObjC::SynthBlockInitExpr(BlockExpr *Exp,
         if (HasLocalVariableExternalStorage(*I)) {
           QualType QT = (*I)->getType();
           QT = Context->getPointerType(QT);
-          Exp = new (Context) UnaryOperator(Exp, UO_AddrOf, QT, VK_RValue,
+          Exp = UnaryOperator::Create(const_cast<ASTContext &>(*Context), Exp,
-                                            OK_Ordinary, SourceLocation(),
+                                      UO_AddrOf, QT, VK_RValue, OK_Ordinary,
-                                            false);
+                                      SourceLocation(), false,
+                                      FPOptions(Context->getLangOpts()));
         }
       }
       InitExprs.push_back(Exp);
@@ -4509,9 +4515,10 @@ Stmt *RewriteObjC::SynthBlockInitExpr(BlockExpr *Exp,
       // captured nested byref variable has its address passed. Do not take
       // its address again.
       if (!isNestedCapturedVar)
-        Exp = new (Context) UnaryOperator(
+        Exp = UnaryOperator::Create(
-            Exp, UO_AddrOf, Context->getPointerType(Exp->getType()), VK_RValue,
+            const_cast<ASTContext &>(*Context), Exp, UO_AddrOf,
-            OK_Ordinary, SourceLocation(), false);
+            Context->getPointerType(Exp->getType()), VK_RValue, OK_Ordinary,
+            SourceLocation(), false, FPOptions(Context->getLangOpts()));
       Exp = NoTypeInfoCStyleCastExpr(Context, castT, CK_BitCast, Exp);
       InitExprs.push_back(Exp);
     }
@@ -4527,9 +4534,10 @@ Stmt *RewriteObjC::SynthBlockInitExpr(BlockExpr *Exp,
   }
   NewRep = CallExpr::Create(*Context, DRE, InitExprs, FType, VK_LValue,
                             SourceLocation());
-  NewRep = new (Context) UnaryOperator(
+  NewRep = UnaryOperator::Create(
-      NewRep, UO_AddrOf, Context->getPointerType(NewRep->getType()), VK_RValue,
+      const_cast<ASTContext &>(*Context), NewRep, UO_AddrOf,
-      OK_Ordinary, SourceLocation(), false);
+      Context->getPointerType(NewRep->getType()), VK_RValue, OK_Ordinary,
+      SourceLocation(), false, FPOptions(Context->getLangOpts()));
   NewRep = NoTypeInfoCStyleCastExpr(Context, FType, CK_BitCast,
                                     NewRep);
   BlockDeclRefs.clear();

clang/lib/Parse/ParseDeclCXX.cpp

@@ -3365,6 +3365,14 @@ void Parser::ParseCXXMemberSpecification(SourceLocation RecordLoc,
     // are complete and we can parse the delayed portions of method
     // declarations and the lexed inline method definitions, along with any
     // delayed attributes.
+
+    // Save the state of Sema.FPFeatures, and change the setting
+    // to the levels specified on the command line.  Previous level
+    // will be restored when the RAII object is destroyed.
+    Sema::FPFeaturesStateRAII SaveFPFeaturesState(Actions);
+    FPOptions fpOptions(getLangOpts());
+    Actions.CurFPFeatures.getFromOpaqueInt(fpOptions.getAsOpaqueInt());
+
     SourceLocation SavedPrevTokLocation = PrevTokLocation;
     ParseLexedPragmas(getCurrentClass());
     ParseLexedAttributes(getCurrentClass());

clang/lib/Parse/ParsePragma.cpp

@@ -184,6 +184,13 @@ private:
   Sema &Actions;
 };
 
+struct PragmaFloatControlHandler : public PragmaHandler {
+  PragmaFloatControlHandler(Sema &Actions)
+      : PragmaHandler("float_control") {}
+  void HandlePragma(Preprocessor &PP, PragmaIntroducer Introducer,
+                    Token &FirstToken) override;
+};
+
 struct PragmaMSPointersToMembers : public PragmaHandler {
   explicit PragmaMSPointersToMembers() : PragmaHandler("pointers_to_members") {}
   void HandlePragma(Preprocessor &PP, PragmaIntroducer Introducer,
@@ -334,6 +341,8 @@ void Parser::initializePragmaHandlers() {
     PP.AddPragmaHandler(MSCommentHandler.get());
   }
 
+  FloatControlHandler = std::make_unique<PragmaFloatControlHandler>(Actions);
+  PP.AddPragmaHandler(FloatControlHandler.get());
   if (getLangOpts().MicrosoftExt) {
     MSDetectMismatchHandler =
         std::make_unique<PragmaDetectMismatchHandler>(Actions);
@@ -438,6 +447,8 @@ void Parser::resetPragmaHandlers() {
   PP.RemovePragmaHandler("clang", PCSectionHandler.get());
   PCSectionHandler.reset();
 
+  PP.RemovePragmaHandler(FloatControlHandler.get());
+  FloatControlHandler.reset();
   if (getLangOpts().MicrosoftExt) {
     PP.RemovePragmaHandler(MSDetectMismatchHandler.get());
     MSDetectMismatchHandler.reset();
@@ -646,6 +657,22 @@ void Parser::HandlePragmaFPContract() {
   ConsumeAnnotationToken();
 }
 
+void Parser::HandlePragmaFloatControl() {
+  assert(Tok.is(tok::annot_pragma_float_control));
+
+  // The value that is held on the PragmaFloatControlStack encodes
+  // the PragmaFloatControl kind and the MSStackAction kind
+  // into a single 32-bit word. The MsStackAction is the high 16 bits
+  // and the FloatControl is the lower 16 bits. Use shift and bit-and
+  // to decode the parts.
+  uintptr_t Value = reinterpret_cast<uintptr_t>(Tok.getAnnotationValue());
+  Sema::PragmaMsStackAction Action =
+      static_cast<Sema::PragmaMsStackAction>((Value >> 16) & 0xFFFF);
+  PragmaFloatControlKind Kind = PragmaFloatControlKind(Value & 0xFFFF);
+  SourceLocation PragmaLoc = ConsumeAnnotationToken();
+  Actions.ActOnPragmaFloatControl(PragmaLoc, Action, Kind);
+}
+
 void Parser::HandlePragmaFEnvAccess() {
   assert(Tok.is(tok::annot_pragma_fenv_access));
   tok::OnOffSwitch OOS =
@@ -665,8 +692,8 @@ void Parser::HandlePragmaFEnvAccess() {
     break;
   }
 
-  Actions.ActOnPragmaFEnvAccess(FPC);
+  SourceLocation PragmaLoc = ConsumeAnnotationToken();
-  ConsumeAnnotationToken();
+  Actions.ActOnPragmaFEnvAccess(PragmaLoc, FPC);
 }
 
 
@@ -2489,6 +2516,129 @@ void PragmaMSPragma::HandlePragma(Preprocessor &PP,
   PP.EnterToken(AnnotTok, /*IsReinject*/ false);
 }
 
+/// Handle the \#pragma float_control extension.
+///
+/// The syntax is:
+/// \code
+///   #pragma float_control(keyword[, setting] [,push])
+/// \endcode
+/// Where 'keyword' and 'setting' are identifiers.
+// 'keyword' can be: precise, except, push, pop
+// 'setting' can be: on, off
+/// The optional arguments 'setting' and 'push' are supported only
+/// when the keyword is 'precise' or 'except'.
+void PragmaFloatControlHandler::HandlePragma(Preprocessor &PP,
+                                             PragmaIntroducer Introducer,
+                                             Token &Tok) {
+  Sema::PragmaMsStackAction Action = Sema::PSK_Set;
+  SourceLocation FloatControlLoc = Tok.getLocation();
+  PP.Lex(Tok);
+  if (Tok.isNot(tok::l_paren)) {
+    PP.Diag(FloatControlLoc, diag::err_expected) << tok::l_paren;
+    return;
+  }
+
+  // Read the identifier.
+  PP.Lex(Tok);
+  if (Tok.isNot(tok::identifier)) {
+    PP.Diag(Tok.getLocation(), diag::err_pragma_float_control_malformed);
+    return;
+  }
+
+  // Verify that this is one of the float control options.
+  IdentifierInfo *II = Tok.getIdentifierInfo();
+  PragmaFloatControlKind Kind =
+      llvm::StringSwitch<PragmaFloatControlKind>(II->getName())
+          .Case("precise", PFC_Precise)
+          .Case("except", PFC_Except)
+          .Case("push", PFC_Push)
+          .Case("pop", PFC_Pop)
+          .Default(PFC_Unknown);
+  PP.Lex(Tok); // the identifier
+  if (Kind == PFC_Unknown) {
+    PP.Diag(Tok.getLocation(), diag::err_pragma_float_control_malformed);
+    return;
+  } else if (Kind == PFC_Push || Kind == PFC_Pop) {
+    if (Tok.isNot(tok::r_paren)) {
+      PP.Diag(Tok.getLocation(), diag::err_pragma_float_control_malformed);
+      return;
+    }
+    PP.Lex(Tok); // Eat the r_paren
+    Action = (Kind == PFC_Pop) ? Sema::PSK_Pop : Sema::PSK_Push;
+  } else {
+    if (Tok.is(tok::r_paren))
+      // Selecting Precise or Except
+      PP.Lex(Tok); // the r_paren
+    else if (Tok.isNot(tok::comma)) {
+      PP.Diag(Tok.getLocation(), diag::err_pragma_float_control_malformed);
+      return;
+    } else {
+      PP.Lex(Tok); // ,
+      if (!Tok.isAnyIdentifier()) {
+        PP.Diag(Tok.getLocation(), diag::err_pragma_float_control_malformed);
+        return;
+      }
+      StringRef PushOnOff = Tok.getIdentifierInfo()->getName();
+      if (PushOnOff == "on")
+        // Kind is set correctly
+        ;
+      else if (PushOnOff == "off") {
+        if (Kind == PFC_Precise)
+          Kind = PFC_NoPrecise;
+        if (Kind == PFC_Except)
+          Kind = PFC_NoExcept;
+      } else if (PushOnOff == "push") {
+        Action = Sema::PSK_Push_Set;
+      } else {
+        PP.Diag(Tok.getLocation(), diag::err_pragma_float_control_malformed);
+        return;
+      }
+      PP.Lex(Tok); // the identifier
+      if (Tok.is(tok::comma)) {
+        PP.Lex(Tok); // ,
+        if (!Tok.isAnyIdentifier()) {
+          PP.Diag(Tok.getLocation(), diag::err_pragma_float_control_malformed);
+          return;
+        }
+        StringRef ExpectedPush = Tok.getIdentifierInfo()->getName();
+        if (ExpectedPush == "push") {
+          Action = Sema::PSK_Push_Set;
+        } else {
+          PP.Diag(Tok.getLocation(), diag::err_pragma_float_control_malformed);
+          return;
+        }
+        PP.Lex(Tok); // the push identifier
+      }
+      if (Tok.isNot(tok::r_paren)) {
+        PP.Diag(Tok.getLocation(), diag::err_pragma_float_control_malformed);
+        return;
+      }
+      PP.Lex(Tok); // the r_paren
+    }
+  }
+  SourceLocation EndLoc = Tok.getLocation();
+  if (Tok.isNot(tok::eod)) {
+    PP.Diag(Tok.getLocation(), diag::warn_pragma_extra_tokens_at_eol)
+        << "float_control";
+    return;
+  }
+
+  // Note: there is no accomodation for PP callback for this pragma.
+
+  // Enter the annotation.
+  auto TokenArray = std::make_unique<Token[]>(1);
+  TokenArray[0].startToken();
+  TokenArray[0].setKind(tok::annot_pragma_float_control);
+  TokenArray[0].setLocation(FloatControlLoc);
+  TokenArray[0].setAnnotationEndLoc(EndLoc);
+  // Create an encoding of Action and Value by shifting the Action into
+  // the high 16 bits then union with the Kind.
+  TokenArray[0].setAnnotationValue(reinterpret_cast<void *>(
+      static_cast<uintptr_t>((Action << 16) | (Kind & 0xFFFF))));
+  PP.EnterTokenStream(std::move(TokenArray), 1,
+                      /*DisableMacroExpansion=*/false, /*IsReinject=*/false);
+}
+
 /// Handle the Microsoft \#pragma detect_mismatch extension.
 ///
 /// The syntax is:
@@ -2749,7 +2899,7 @@ void PragmaFPHandler::HandlePragma(Preprocessor &PP,
 
     auto *AnnotValue = new (PP.getPreprocessorAllocator())
         TokFPAnnotValue{*FlagKind, *FlagValue};
-    // Generate the loop hint token.
+    // Generate the fp annotation token.
     Token FPTok;
     FPTok.startToken();
     FPTok.setKind(tok::annot_pragma_fp);

clang/lib/Parse/ParseStmt.cpp

@@ -354,13 +354,13 @@ Retry:
 
   case tok::annot_pragma_fp_contract:
     ProhibitAttributes(Attrs);
-    Diag(Tok, diag::err_pragma_fp_contract_scope);
+    Diag(Tok, diag::err_pragma_file_or_compound_scope) << "fp_contract";
     ConsumeAnnotationToken();
     return StmtError();
 
   case tok::annot_pragma_fp:
     ProhibitAttributes(Attrs);
-    Diag(Tok, diag::err_pragma_fp_scope);
+    Diag(Tok, diag::err_pragma_file_or_compound_scope) << "clang fp";
     ConsumeAnnotationToken();
     return StmtError();
 
@@ -369,6 +369,12 @@ Retry:
     HandlePragmaFEnvAccess();
     return StmtEmpty();
 
+  case tok::annot_pragma_float_control:
+    ProhibitAttributes(Attrs);
+    Diag(Tok, diag::err_pragma_file_or_compound_scope) << "float_control";
+    ConsumeAnnotationToken();
+    return StmtError();
+
   case tok::annot_pragma_opencl_extension:
     ProhibitAttributes(Attrs);
     HandlePragmaOpenCLExtension();
@@ -937,6 +943,9 @@ void Parser::ParseCompoundStatementLeadingPragmas() {
     case tok::annot_pragma_fenv_access:
       HandlePragmaFEnvAccess();
       break;
+    case tok::annot_pragma_float_control:
+      HandlePragmaFloatControl();
+      break;
     case tok::annot_pragma_ms_pointers_to_members:
       HandlePragmaMSPointersToMembers();
       break;

clang/lib/Parse/Parser.cpp

@@ -752,6 +752,9 @@ Parser::ParseExternalDeclaration(ParsedAttributesWithRange &attrs,
   case tok::annot_pragma_fenv_access:
     HandlePragmaFEnvAccess();
     return nullptr;
+  case tok::annot_pragma_float_control:
+    HandlePragmaFloatControl();
+    return nullptr;
   case tok::annot_pragma_fp:
     HandlePragmaFP();
     break;

clang/lib/Sema/Sema.cpp

@@ -159,7 +159,8 @@ Sema::Sema(Preprocessor &pp, ASTContext &ctxt, ASTConsumer &consumer,
           LangOpts.getMSPointerToMemberRepresentationMethod()),
       VtorDispStack(LangOpts.getVtorDispMode()), PackStack(0),
       DataSegStack(nullptr), BSSSegStack(nullptr), ConstSegStack(nullptr),
-      CodeSegStack(nullptr), CurInitSeg(nullptr), VisContext(nullptr),
+      CodeSegStack(nullptr), FpPragmaStack(CurFPFeatures.getAsOpaqueInt()),
+      CurInitSeg(nullptr), VisContext(nullptr),
       PragmaAttributeCurrentTargetDecl(nullptr),
       IsBuildingRecoveryCallExpr(false), Cleanup{}, LateTemplateParser(nullptr),
       LateTemplateParserCleanup(nullptr), OpaqueParser(nullptr), IdResolver(pp),

clang/lib/Sema/SemaAttr.cpp

@@ -407,6 +407,65 @@ void Sema::ActOnPragmaDetectMismatch(SourceLocation Loc, StringRef Name,
   Consumer.HandleTopLevelDecl(DeclGroupRef(PDMD));
 }
 
+void Sema::ActOnPragmaFloatControl(SourceLocation Loc,
+                                   PragmaMsStackAction Action,
+                                   PragmaFloatControlKind Value) {
+  auto NewValue = FpPragmaStack.CurrentValue;
+  FPOptions NewFPFeatures(NewValue);
+  if ((Action == PSK_Push_Set || Action == PSK_Push || Action == PSK_Pop) &&
+      !CurContext->isTranslationUnit()) {
+    // Push and pop can only occur at file scope.
+    Diag(Loc, diag::err_pragma_fc_pp_scope);
+    return;
+  }
+  switch (Value) {
+  default:
+    llvm_unreachable("invalid pragma float_control kind");
+  case PFC_Precise:
+    CurFPFeatures.setFPPreciseEnabled(true);
+    NewValue = CurFPFeatures.getAsOpaqueInt();
+    FpPragmaStack.Act(Loc, Action, StringRef(), NewValue);
+    break;
+  case PFC_NoPrecise:
+    if (CurFPFeatures.getExceptionMode() == LangOptions::FPE_Strict)
+      Diag(Loc, diag::err_pragma_fc_noprecise_requires_noexcept);
+    else if (CurFPFeatures.allowFEnvAccess())
+      Diag(Loc, diag::err_pragma_fc_noprecise_requires_nofenv);
+    else
+      CurFPFeatures.setFPPreciseEnabled(false);
+    NewValue = CurFPFeatures.getAsOpaqueInt();
+    FpPragmaStack.Act(Loc, Action, StringRef(), NewValue);
+    break;
+  case PFC_Except:
+    if (!isPreciseFPEnabled())
+      Diag(Loc, diag::err_pragma_fc_except_requires_precise);
+    else
+      CurFPFeatures.setExceptionMode(LangOptions::FPE_Strict);
+    NewValue = CurFPFeatures.getAsOpaqueInt();
+    FpPragmaStack.Act(Loc, Action, StringRef(), NewValue);
+    break;
+  case PFC_NoExcept:
+    CurFPFeatures.setExceptionMode(LangOptions::FPE_Ignore);
+    NewValue = CurFPFeatures.getAsOpaqueInt();
+    FpPragmaStack.Act(Loc, Action, StringRef(), NewValue);
+    break;
+  case PFC_Push:
+    Action = Sema::PSK_Push_Set;
+    FpPragmaStack.Act(Loc, Action, StringRef(), NewFPFeatures.getAsOpaqueInt());
+    break;
+  case PFC_Pop:
+    if (FpPragmaStack.Stack.empty()) {
+      Diag(Loc, diag::warn_pragma_pop_failed) << "float_control"
+                                              << "stack empty";
+      return;
+    }
+    FpPragmaStack.Act(Loc, Action, StringRef(), NewFPFeatures.getAsOpaqueInt());
+    NewValue = FpPragmaStack.CurrentValue;
+    CurFPFeatures.getFromOpaqueInt(NewValue);
+    break;
+  }
+}
+
 void Sema::ActOnPragmaMSPointersToMembers(
     LangOptions::PragmaMSPointersToMembersKind RepresentationMethod,
     SourceLocation PragmaLoc) {
@@ -948,9 +1007,16 @@ void Sema::setExceptionMode(LangOptions::FPExceptionModeKind FPE) {
   CurFPFeatures.setExceptionMode(FPE);
 }
 
-void Sema::ActOnPragmaFEnvAccess(LangOptions::FEnvAccessModeKind FPC) {
+void Sema::ActOnPragmaFEnvAccess(SourceLocation Loc,
+                                 LangOptions::FEnvAccessModeKind FPC) {
   switch (FPC) {
   case LangOptions::FEA_On:
+    // Verify Microsoft restriction:
+    // You can't enable fenv_access unless precise semantics are enabled.
+    // Precise semantics can be enabled either by the float_control
+    // pragma, or by using the /fp:precise or /fp:strict compiler options
+    if (!isPreciseFPEnabled())
+      Diag(Loc, diag::err_pragma_fenv_requires_precise);
     CurFPFeatures.setAllowFEnvAccess();
     break;
   case LangOptions::FEA_Off:
@@ -959,7 +1025,6 @@ void Sema::ActOnPragmaFEnvAccess(LangOptions::FEnvAccessModeKind FPC) {
   }
 }
 
-
 void Sema::PushNamespaceVisibilityAttr(const VisibilityAttr *Attr,
                                        SourceLocation Loc) {
   // Visibility calculations will consider the namespace's visibility.

clang/lib/Sema/SemaDeclCXX.cpp

@@ -13455,13 +13455,13 @@ buildMemcpyForAssignmentOp(Sema &S, SourceLocation Loc, QualType T,
   // directly construct UnaryOperators here because semantic analysis
   // does not permit us to take the address of an xvalue.
   Expr *From = FromB.build(S, Loc);
-  From = new (S.Context) UnaryOperator(From, UO_AddrOf,
+  From = UnaryOperator::Create(
-                         S.Context.getPointerType(From->getType()),
+      S.Context, From, UO_AddrOf, S.Context.getPointerType(From->getType()),
-                         VK_RValue, OK_Ordinary, Loc, false);
+      VK_RValue, OK_Ordinary, Loc, false, S.CurFPFeatures);
   Expr *To = ToB.build(S, Loc);
-  To = new (S.Context) UnaryOperator(To, UO_AddrOf,
+  To = UnaryOperator::Create(S.Context, To, UO_AddrOf,
-                       S.Context.getPointerType(To->getType()),
+                             S.Context.getPointerType(To->getType()), VK_RValue,
-                       VK_RValue, OK_Ordinary, Loc, false);
+                             OK_Ordinary, Loc, false, S.CurFPFeatures);
 
   const Type *E = T->getBaseElementTypeUnsafe();
   bool NeedsCollectableMemCpy =
@@ -13703,9 +13703,9 @@ buildSingleCopyAssignRecursively(Sema &S, SourceLocation Loc, QualType T,
   // Create the pre-increment of the iteration variable. We can determine
   // whether the increment will overflow based on the value of the array
   // bound.
-  Expr *Increment = new (S.Context)
+  Expr *Increment = UnaryOperator::Create(
-      UnaryOperator(IterationVarRef.build(S, Loc), UO_PreInc, SizeType,
+      S.Context, IterationVarRef.build(S, Loc), UO_PreInc, SizeType, VK_LValue,
-                    VK_LValue, OK_Ordinary, Loc, Upper.isMaxValue());
+      OK_Ordinary, Loc, Upper.isMaxValue(), S.CurFPFeatures);
 
   // Construct the loop that copies all elements of this array.
   return S.ActOnForStmt(

clang/lib/Sema/SemaExpr.cpp

@@ -13662,14 +13662,6 @@ ExprResult Sema::CreateBuiltinBinOp(SourceLocation OpLoc,
   if (ResultTy.isNull() || LHS.isInvalid() || RHS.isInvalid())
     return ExprError();
 
-  if (ResultTy->isRealFloatingType() &&
-      (getLangOpts().getFPRoundingMode() != RoundingMode::NearestTiesToEven ||
-       getLangOpts().getFPExceptionMode() != LangOptions::FPE_Ignore))
-    // Mark the current function as usng floating point constrained intrinsics
-    if (FunctionDecl *F = dyn_cast<FunctionDecl>(CurContext)) {
-      F->setUsesFPIntrin(true);
-    }
-
   // Some of the binary operations require promoting operands of half vector to
   // float vectors and truncating the result back to half vector. For now, we do
   // this only when HalfArgsAndReturn is set (that is, when the target is arm or
@@ -14319,8 +14311,8 @@ ExprResult Sema::CreateBuiltinUnaryOp(SourceLocation OpLoc,
   if (Opc != UO_AddrOf && Opc != UO_Deref)
     CheckArrayAccess(Input.get());
 
-  auto *UO = new (Context)
+  auto *UO = UnaryOperator::Create(Context, Input.get(), Opc, resultType, VK,
-      UnaryOperator(Input.get(), Opc, resultType, VK, OK, OpLoc, CanOverflow);
+                                   OK, OpLoc, CanOverflow, CurFPFeatures);
 
   if (Opc == UO_Deref && UO->getType()->hasAttr(attr::NoDeref) &&
       !isa<ArrayType>(UO->getType().getDesugaredType(Context)))

clang/lib/Sema/SemaExprObjC.cpp

@@ -4427,9 +4427,9 @@ Expr *Sema::stripARCUnbridgedCast(Expr *e) {
   } else if (UnaryOperator *uo = dyn_cast<UnaryOperator>(e)) {
     assert(uo->getOpcode() == UO_Extension);
     Expr *sub = stripARCUnbridgedCast(uo->getSubExpr());
-    return new (Context)
+    return UnaryOperator::Create(Context, sub, UO_Extension, sub->getType(),
-        UnaryOperator(sub, UO_Extension, sub->getType(), sub->getValueKind(),
+                                 sub->getValueKind(), sub->getObjectKind(),
-                      sub->getObjectKind(), uo->getOperatorLoc(), false);
+                                 uo->getOperatorLoc(), false, CurFPFeatures);
   } else if (GenericSelectionExpr *gse = dyn_cast<GenericSelectionExpr>(e)) {
     assert(!gse->isResultDependent());
 

clang/lib/Sema/SemaOverload.cpp

@@ -13001,8 +13001,9 @@ Sema::CreateOverloadedUnaryOp(SourceLocation OpLoc, UnaryOperatorKind Opc,
 
   if (Input->isTypeDependent()) {
     if (Fns.empty())
-      return new (Context) UnaryOperator(Input, Opc, Context.DependentTy,
+      return UnaryOperator::Create(Context, Input, Opc, Context.DependentTy,
-                                         VK_RValue, OK_Ordinary, OpLoc, false);
+                                   VK_RValue, OK_Ordinary, OpLoc, false,
+                                   CurFPFeatures);
 
     CXXRecordDecl *NamingClass = nullptr; // lookup ignores member operators
     UnresolvedLookupExpr *Fn = UnresolvedLookupExpr::Create(
@@ -14802,9 +14803,9 @@ Expr *Sema::FixOverloadedFunctionReference(Expr *E, DeclAccessPair Found,
         if (Context.getTargetInfo().getCXXABI().isMicrosoft())
           (void)isCompleteType(UnOp->getOperatorLoc(), MemPtrType);
 
-        return new (Context) UnaryOperator(SubExpr, UO_AddrOf, MemPtrType,
+        return UnaryOperator::Create(
-                                           VK_RValue, OK_Ordinary,
+            Context, SubExpr, UO_AddrOf, MemPtrType, VK_RValue, OK_Ordinary,
-                                           UnOp->getOperatorLoc(), false);
+            UnOp->getOperatorLoc(), false, CurFPFeatures);
       }
     }
     Expr *SubExpr = FixOverloadedFunctionReference(UnOp->getSubExpr(),
@@ -14812,10 +14813,9 @@ Expr *Sema::FixOverloadedFunctionReference(Expr *E, DeclAccessPair Found,
     if (SubExpr == UnOp->getSubExpr())
       return UnOp;
 
-    return new (Context) UnaryOperator(SubExpr, UO_AddrOf,
+    return UnaryOperator::Create(
-                                     Context.getPointerType(SubExpr->getType()),
+        Context, SubExpr, UO_AddrOf, Context.getPointerType(SubExpr->getType()),
-                                       VK_RValue, OK_Ordinary,
+        VK_RValue, OK_Ordinary, UnOp->getOperatorLoc(), false, CurFPFeatures);
-                                       UnOp->getOperatorLoc(), false);
   }
 
   if (UnresolvedLookupExpr *ULE = dyn_cast<UnresolvedLookupExpr>(E)) {

clang/lib/Sema/SemaPseudoObject.cpp

@@ -127,12 +127,10 @@ namespace {
       if (UnaryOperator *uop = dyn_cast<UnaryOperator>(e)) {
         assert(uop->getOpcode() == UO_Extension);
         e = rebuild(uop->getSubExpr());
-        return new (S.Context) UnaryOperator(e, uop->getOpcode(),
+        return UnaryOperator::Create(
-                                             uop->getType(),
+            S.Context, e, uop->getOpcode(), uop->getType(), uop->getValueKind(),
-                                             uop->getValueKind(),
+            uop->getObjectKind(), uop->getOperatorLoc(), uop->canOverflow(),
-                                             uop->getObjectKind(),
+            S.CurFPFeatures);
-                                             uop->getOperatorLoc(),
-                                             uop->canOverflow());
       }
 
       if (GenericSelectionExpr *gse = dyn_cast<GenericSelectionExpr>(e)) {
@@ -526,12 +524,14 @@ PseudoOpBuilder::buildIncDecOperation(Scope *Sc, SourceLocation opcLoc,
       (result.get()->isTypeDependent() || CanCaptureValue(result.get())))
     setResultToLastSemantic();
 
-  UnaryOperator *syntactic = new (S.Context) UnaryOperator(
+  UnaryOperator *syntactic =
-      syntacticOp, opcode, resultType, VK_LValue, OK_Ordinary, opcLoc,
+      UnaryOperator::Create(S.Context, syntacticOp, opcode, resultType,
-      !resultType->isDependentType()
+                            VK_LValue, OK_Ordinary, opcLoc,
-          ? S.Context.getTypeSize(resultType) >=
+                            !resultType->isDependentType()
-                S.Context.getTypeSize(S.Context.IntTy)
+                                ? S.Context.getTypeSize(resultType) >=
-          : false);
+                                      S.Context.getTypeSize(S.Context.IntTy)
+                                : false,
+                            S.CurFPFeatures);
   return complete(syntactic);
 }
 
@@ -1551,8 +1551,9 @@ ExprResult Sema::checkPseudoObjectIncDec(Scope *Sc, SourceLocation opcLoc,
                                          UnaryOperatorKind opcode, Expr *op) {
   // Do nothing if the operand is dependent.
   if (op->isTypeDependent())
-    return new (Context) UnaryOperator(op, opcode, Context.DependentTy,
+    return UnaryOperator::Create(Context, op, opcode, Context.DependentTy,
-                                       VK_RValue, OK_Ordinary, opcLoc, false);
+                                 VK_RValue, OK_Ordinary, opcLoc, false,
+                                 CurFPFeatures);
 
   assert(UnaryOperator::isIncrementDecrementOp(opcode));
   Expr *opaqueRef = op->IgnoreParens();
@@ -1636,9 +1637,10 @@ Expr *Sema::recreateSyntacticForm(PseudoObjectExpr *E) {
   Expr *syntax = E->getSyntacticForm();
   if (UnaryOperator *uop = dyn_cast<UnaryOperator>(syntax)) {
     Expr *op = stripOpaqueValuesFromPseudoObjectRef(*this, uop->getSubExpr());
-    return new (Context) UnaryOperator(
+    return UnaryOperator::Create(Context, op, uop->getOpcode(), uop->getType(),
-        op, uop->getOpcode(), uop->getType(), uop->getValueKind(),
+                                 uop->getValueKind(), uop->getObjectKind(),
-        uop->getObjectKind(), uop->getOperatorLoc(), uop->canOverflow());
+                                 uop->getOperatorLoc(), uop->canOverflow(),
+                                 CurFPFeatures);
   } else if (CompoundAssignOperator *cop
                = dyn_cast<CompoundAssignOperator>(syntax)) {
     Expr *lhs = stripOpaqueValuesFromPseudoObjectRef(*this, cop->getLHS());

clang/lib/Sema/SemaStmt.cpp

@@ -394,6 +394,11 @@ StmtResult Sema::ActOnCompoundStmt(SourceLocation L, SourceLocation R,
                                    ArrayRef<Stmt *> Elts, bool isStmtExpr) {
   const unsigned NumElts = Elts.size();
 
+  // Mark the current function as usng floating point constrained intrinsics
+  if (getCurFPFeatures().isFPConstrained())
+    if (FunctionDecl *F = dyn_cast<FunctionDecl>(CurContext))
+      F->setUsesFPIntrin(true);
+
   // If we're in C89 mode, check that we don't have any decls after stmts.  If
   // so, emit an extension diagnostic.
   if (!getLangOpts().C99 && !getLangOpts().CPlusPlus) {

clang/lib/Serialization/ASTReader.cpp

@@ -3779,6 +3779,29 @@ ASTReader::ReadASTBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
       break;
     }
 
+    case FLOAT_CONTROL_PRAGMA_OPTIONS: {
+      if (Record.size() < 3) {
+        Error("invalid pragma pack record");
+        return Failure;
+      }
+      FpPragmaCurrentValue = Record[0];
+      FpPragmaCurrentLocation = ReadSourceLocation(F, Record[1]);
+      unsigned NumStackEntries = Record[2];
+      unsigned Idx = 3;
+      // Reset the stack when importing a new module.
+      FpPragmaStack.clear();
+      for (unsigned I = 0; I < NumStackEntries; ++I) {
+        FpPragmaStackEntry Entry;
+        Entry.Value = Record[Idx++];
+        Entry.Location = ReadSourceLocation(F, Record[Idx++]);
+        Entry.PushLocation = ReadSourceLocation(F, Record[Idx++]);
+        FpPragmaStrings.push_back(ReadString(Record, Idx));
+        Entry.SlotLabel = FpPragmaStrings.back();
+        FpPragmaStack.push_back(Entry);
+      }
+      break;
+    }
+
     case DECLS_TO_CHECK_FOR_DEFERRED_DIAGS:
       for (unsigned I = 0, N = Record.size(); I != N; ++I)
         DeclsToCheckForDeferredDiags.push_back(getGlobalDeclID(F, Record[I]));
@@ -7853,6 +7876,34 @@ void ASTReader::UpdateSema() {
       SemaObj->PackStack.CurrentPragmaLocation = PragmaPackCurrentLocation;
     }
   }
+  if (FpPragmaCurrentValue) {
+    // The bottom of the stack might have a default value. It must be adjusted
+    // to the current value to ensure that fp-pragma state is preserved after
+    // popping entries that were included/imported from a PCH/module.
+    bool DropFirst = false;
+    if (!FpPragmaStack.empty() && FpPragmaStack.front().Location.isInvalid()) {
+      assert(FpPragmaStack.front().Value ==
+                 SemaObj->FpPragmaStack.DefaultValue &&
+             "Expected a default pragma float_control value");
+      SemaObj->FpPragmaStack.Stack.emplace_back(
+          FpPragmaStack.front().SlotLabel, SemaObj->FpPragmaStack.CurrentValue,
+          SemaObj->FpPragmaStack.CurrentPragmaLocation,
+          FpPragmaStack.front().PushLocation);
+      DropFirst = true;
+    }
+    for (const auto &Entry :
+         llvm::makeArrayRef(FpPragmaStack).drop_front(DropFirst ? 1 : 0))
+      SemaObj->FpPragmaStack.Stack.emplace_back(
+          Entry.SlotLabel, Entry.Value, Entry.Location, Entry.PushLocation);
+    if (FpPragmaCurrentLocation.isInvalid()) {
+      assert(*FpPragmaCurrentValue == SemaObj->FpPragmaStack.DefaultValue &&
+             "Expected a default pragma float_control value");
+      // Keep the current values.
+    } else {
+      SemaObj->FpPragmaStack.CurrentValue = *FpPragmaCurrentValue;
+      SemaObj->FpPragmaStack.CurrentPragmaLocation = FpPragmaCurrentLocation;
+    }
+  }
 }
 
 IdentifierInfo *ASTReader::get(StringRef Name) {

clang/lib/Serialization/ASTReaderStmt.cpp

@@ -682,10 +682,14 @@ void ASTStmtReader::VisitParenListExpr(ParenListExpr *E) {
 
 void ASTStmtReader::VisitUnaryOperator(UnaryOperator *E) {
   VisitExpr(E);
+  bool hasFP_Features = Record.readInt();
+  assert(hasFP_Features == E->hasStoredFPFeatures());
   E->setSubExpr(Record.readSubExpr());
   E->setOpcode((UnaryOperator::Opcode)Record.readInt());
   E->setOperatorLoc(readSourceLocation());
   E->setCanOverflow(Record.readInt());
+  if (hasFP_Features)
+    E->setStoredFPFeatures(FPOptions(Record.readInt()));
 }
 
 void ASTStmtReader::VisitOffsetOfExpr(OffsetOfExpr *E) {
@@ -2900,7 +2904,8 @@ Stmt *ASTReader::ReadStmtFromStream(ModuleFile &F) {
       break;
 
     case EXPR_UNARY_OPERATOR:
-      S = new (Context) UnaryOperator(Empty);
+      S = UnaryOperator::CreateEmpty(Context,
+                                     Record[ASTStmtReader::NumExprFields]);
       break;
 
     case EXPR_OFFSETOF:

clang/lib/Serialization/ASTWriter.cpp

@@ -4139,6 +4139,26 @@ void ASTWriter::WritePackPragmaOptions(Sema &SemaRef) {
   Stream.EmitRecord(PACK_PRAGMA_OPTIONS, Record);
 }
 
+/// Write the state of 'pragma float_control' at the end of the module.
+void ASTWriter::WriteFloatControlPragmaOptions(Sema &SemaRef) {
+  // Don't serialize pragma float_control state for modules,
+  // since it should only take effect on a per-submodule basis.
+  if (WritingModule)
+    return;
+
+  RecordData Record;
+  Record.push_back(SemaRef.FpPragmaStack.CurrentValue);
+  AddSourceLocation(SemaRef.FpPragmaStack.CurrentPragmaLocation, Record);
+  Record.push_back(SemaRef.FpPragmaStack.Stack.size());
+  for (const auto &StackEntry : SemaRef.FpPragmaStack.Stack) {
+    Record.push_back(StackEntry.Value);
+    AddSourceLocation(StackEntry.PragmaLocation, Record);
+    AddSourceLocation(StackEntry.PragmaPushLocation, Record);
+    AddString(StackEntry.StackSlotLabel, Record);
+  }
+  Stream.EmitRecord(FLOAT_CONTROL_PRAGMA_OPTIONS, Record);
+}
+
 void ASTWriter::WriteModuleFileExtension(Sema &SemaRef,
                                          ModuleFileExtensionWriter &Writer) {
   // Enter the extension block.
@@ -4867,6 +4887,7 @@ ASTFileSignature ASTWriter::WriteASTCore(Sema &SemaRef, StringRef isysroot,
     WriteMSPointersToMembersPragmaOptions(SemaRef);
   }
   WritePackPragmaOptions(SemaRef);
+  WriteFloatControlPragmaOptions(SemaRef);
 
   // Some simple statistics
   RecordData::value_type Record[] = {

clang/lib/Serialization/ASTWriterStmt.cpp

@@ -702,10 +702,16 @@ void ASTStmtWriter::VisitParenListExpr(ParenListExpr *E) {
 
 void ASTStmtWriter::VisitUnaryOperator(UnaryOperator *E) {
   VisitExpr(E);
+  bool HasFPFeatures = E->hasStoredFPFeatures();
+  // Write this first for easy access when deserializing, as they affect the
+  // size of the UnaryOperator.
+  Record.push_back(HasFPFeatures);
   Record.AddStmt(E->getSubExpr());
   Record.push_back(E->getOpcode()); // FIXME: stable encoding
   Record.AddSourceLocation(E->getOperatorLoc());
   Record.push_back(E->canOverflow());
+  if (HasFPFeatures)
+    Record.push_back(E->getStoredFPFeatures().getAsOpaqueInt());
   Code = serialization::EXPR_UNARY_OPERATOR;
 }
 

clang/test/CodeGen/builtins-nvptx.c

@@ -1,11 +1,11 @@
 // REQUIRES: nvptx-registered-target
-// RUN: %clang_cc1 -triple nvptx-unknown-unknown -target-cpu sm_60 \
+// RUN: %clang_cc1 -ffp-contract=off -triple nvptx-unknown-unknown -target-cpu sm_60 \
 // RUN:            -fcuda-is-device -S -emit-llvm -o - -x cuda %s \
 // RUN:   | FileCheck -check-prefix=CHECK -check-prefix=LP32 %s
-// RUN: %clang_cc1 -triple nvptx64-unknown-unknown -target-cpu sm_60 \
+// RUN: %clang_cc1 -ffp-contract=off -triple nvptx64-unknown-unknown -target-cpu sm_60 \
 // RUN:            -fcuda-is-device -S -emit-llvm -o - -x cuda %s \
 // RUN:   | FileCheck -check-prefix=CHECK -check-prefix=LP64 %s
-// RUN: %clang_cc1 -triple nvptx64-unknown-unknown -target-cpu sm_61 \
+// RUN: %clang_cc1 -ffp-contract=off -triple nvptx64-unknown-unknown -target-cpu sm_61 \
 // RUN:            -fcuda-is-device -S -emit-llvm -o - -x cuda %s \
 // RUN:   | FileCheck -check-prefix=CHECK -check-prefix=LP64 %s
 // RUN: %clang_cc1 -triple nvptx-unknown-unknown -target-cpu sm_53 \

clang/test/CodeGen/constrained-math-builtins.c

@@ -154,9 +154,9 @@ void bar(float f) {
   (double)f * f - f;
   (long double)-f * f + f;
 
-// CHECK: call float @llvm.experimental.constrained.fmuladd.f32
+  // CHECK: call contract float @llvm.experimental.constrained.fmuladd.f32
-// CHECK: fneg
+  // CHECK: fneg
-// CHECK: call double @llvm.experimental.constrained.fmuladd.f64
+  // CHECK: call contract double @llvm.experimental.constrained.fmuladd.f64
-// CHECK: fneg
+  // CHECK: fneg
-// CHECK: call x86_fp80 @llvm.experimental.constrained.fmuladd.f80
+  // CHECK: call contract x86_fp80 @llvm.experimental.constrained.fmuladd.f80
 };

clang/test/CodeGen/fast-math.c

@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -ffast-math -emit-llvm -o - %s | FileCheck %s
+// RUN: %clang_cc1 -ffast-math -ffp-contract=fast -emit-llvm -o - %s | FileCheck %s
 float f0, f1, f2;
 
 void foo(void) {

clang/test/CodeGen/fp-contract-on-pragma.cpp

@@ -3,7 +3,7 @@
 // Is FP_CONTRACT honored in a simple case?
 float fp_contract_1(float a, float b, float c) {
 // CHECK: _Z13fp_contract_1fff
-// CHECK: tail call float @llvm.fmuladd
+// CHECK: tail call contract float @llvm.fmuladd
 #pragma clang fp contract(on)
   return a * b + c;
 }
@@ -31,7 +31,7 @@ T template_muladd(T a, T b, T c) {
 
 float fp_contract_3(float a, float b, float c) {
   // CHECK: _Z13fp_contract_3fff
-  // CHECK: tail call float @llvm.fmuladd
+  // CHECK: tail call contract float @llvm.fmuladd
   return template_muladd<float>(a, b, c);
 }
 
@@ -45,13 +45,13 @@ class fp_contract_4 {
 
 template class fp_contract_4<int>;
 // CHECK: _ZN13fp_contract_4IiE6methodEfff
-// CHECK: tail call float @llvm.fmuladd
+// CHECK: tail call contract float @llvm.fmuladd
 
 // Check file-scoped FP_CONTRACT
 #pragma clang fp contract(on)
 float fp_contract_5(float a, float b, float c) {
   // CHECK: _Z13fp_contract_5fff
-  // CHECK: tail call float @llvm.fmuladd
+  // CHECK: tail call contract float @llvm.fmuladd
   return a * b + c;
 }
 
@@ -69,8 +69,8 @@ float fp_contract_6(float a, float b, float c) {
 
 float fp_contract_7(float a, float b, float c) {
 // CHECK: _Z13fp_contract_7fff
-// CHECK:  %[[M:.+]] = fmul float %b, 2.000000e+00
+// CHECK:  %[[M:.+]] = fmul contract float %b, 2.000000e+00
-// CHECK-NEXT: fsub float %[[M]], %c
+// CHECK-NEXT: fsub contract float %[[M]], %c
 #pragma clang fp contract(on)
   return (a = 2 * b) - c;
 }

clang/test/CodeGen/fp-contract-pragma.cpp

@@ -2,9 +2,9 @@
 
 // Is FP_CONTRACT honored in a simple case?
 float fp_contract_1(float a, float b, float c) {
-// CHECK: _Z13fp_contract_1fff
+  // CHECK: _Z13fp_contract_1fff
-// CHECK: tail call float @llvm.fmuladd
+  // CHECK: tail call contract float @llvm.fmuladd
-  #pragma STDC FP_CONTRACT ON
+#pragma STDC FP_CONTRACT ON
   return a * b + c;
 }
 
@@ -30,8 +30,8 @@ T template_muladd(T a, T b, T c) {
 }
 
 float fp_contract_3(float a, float b, float c) {
-// CHECK: _Z13fp_contract_3fff
+  // CHECK: _Z13fp_contract_3fff
-// CHECK: tail call float @llvm.fmuladd
+  // CHECK: tail call contract float @llvm.fmuladd
   return template_muladd<float>(a, b, c);
 }
 
@@ -44,13 +44,13 @@ template<typename T> class fp_contract_4 {
 
 template class fp_contract_4<int>;
 // CHECK: _ZN13fp_contract_4IiE6methodEfff
-// CHECK: tail call float @llvm.fmuladd
+// CHECK: tail call contract float @llvm.fmuladd
 
 // Check file-scoped FP_CONTRACT
 #pragma STDC FP_CONTRACT ON
 float fp_contract_5(float a, float b, float c) {
-// CHECK: _Z13fp_contract_5fff
+  // CHECK: _Z13fp_contract_5fff
-// CHECK: tail call float @llvm.fmuladd
+  // CHECK: tail call contract float @llvm.fmuladd
   return a * b + c;
 }
 
@@ -67,25 +67,25 @@ float fp_contract_6(float a, float b, float c) {
 // https://llvm.org/bugs/show_bug.cgi?id=25719
 
 float fp_contract_7(float a, float b, float c) {
-// CHECK: _Z13fp_contract_7fff
+  // CHECK: _Z13fp_contract_7fff
-// CHECK:  %[[M:.+]] = fmul float %b, 2.000000e+00
+  // CHECK:  %[[M:.+]] = fmul contract float %b, 2.000000e+00
-// CHECK-NEXT: fsub float %[[M]], %c
+  // CHECK-NEXT: fsub contract float %[[M]], %c
-  #pragma STDC FP_CONTRACT ON
+#pragma STDC FP_CONTRACT ON
   return (a = 2 * b) - c;
 }
 
 float fp_contract_8(float a, float b, float c) {
-// CHECK: _Z13fp_contract_8fff
+  // CHECK: _Z13fp_contract_8fff
-// CHECK: fneg float %c
+  // CHECK: fneg contract float %c
-// CHECK: tail call float @llvm.fmuladd
+  // CHECK: tail call contract float @llvm.fmuladd
-  #pragma STDC FP_CONTRACT ON
+#pragma STDC FP_CONTRACT ON
   return a * b - c;
 }
 
 float fp_contract_9(float a, float b, float c) {
-// CHECK: _Z13fp_contract_9fff
+  // CHECK: _Z13fp_contract_9fff
-// CHECK: fneg float %a
+  // CHECK: fneg contract float %a
-// CHECK: tail call float @llvm.fmuladd
+  // CHECK: tail call contract float @llvm.fmuladd
-  #pragma STDC FP_CONTRACT ON
+#pragma STDC FP_CONTRACT ON
   return c - a * b;
 }

clang/test/CodeGen/fp-floatcontrol-class.cpp

@@ -0,0 +1,21 @@
+// RUN: %clang_cc1 -ffp-contract=on -triple %itanium_abi_triple -emit-llvm -o - %s | FileCheck %s
+// RUN: %clang_cc1 -ffp-contract=on -triple x86_64-linux-gnu -emit-llvm -o - %s | FileCheck %s
+// RUN: %clang_cc1 -ffp-contract=on -triple x86_64-unknown-unknown -emit-llvm -o - %s | FileCheck %s
+// Verify that float_control does not pertain to initializer expressions
+
+float y();
+float z();
+#pragma float_control(except, on)
+class ON {
+  float w = 2 + y() * z();
+  // CHECK-LABEL: define {{.*}} void @_ZN2ONC2Ev{{.*}}
+  //CHECK: call contract float {{.*}}llvm.fmuladd
+};
+ON on;
+#pragma float_control(except, off)
+class OFF {
+  float w = 2 + y() * z();
+  // CHECK-LABEL: define {{.*}} void @_ZN3OFFC2Ev{{.*}}
+  //CHECK: call contract float {{.*}}llvm.fmuladd
+};
+OFF off;

clang/test/CodeGen/fp-floatcontrol-pragma.cpp

@@ -0,0 +1,47 @@
+// RUN: %clang_cc1 -triple x86_64-linux-gnu -emit-llvm -o - %s | FileCheck %s
+
+float fff(float x, float y) {
+// CHECK-LABEL: define float @_Z3fffff{{.*}}
+// CHECK: entry
+#pragma float_control(except, on)
+  float z;
+  z = z * z;
+  //CHECK: llvm.experimental.constrained.fmul{{.*}}
+  {
+    z = x * y;
+    //CHECK: llvm.experimental.constrained.fmul{{.*}}
+  }
+  {
+// This pragma has no effect since if there are any fp intrin in the
+// function then all the operations need to be fp intrin
+#pragma float_control(except, off)
+    z = z + x * y;
+    //CHECK: llvm.experimental.constrained.fmul{{.*}}
+  }
+  z = z * z;
+  //CHECK: llvm.experimental.constrained.fmul{{.*}}
+  return z;
+}
+float check_precise(float x, float y) {
+  // CHECK-LABEL: define float @_Z13check_preciseff{{.*}}
+  float z;
+  {
+#pragma float_control(precise, on)
+    z = x * y + z;
+    //CHECK: llvm.fmuladd{{.*}}
+  }
+  {
+#pragma float_control(precise, off)
+    z = x * y + z;
+    //CHECK: fmul fast float
+    //CHECK: fadd fast float
+  }
+  return z;
+}
+float fma_test1(float a, float b, float c) {
+// CHECK-LABEL define float @_Z9fma_test1fff{{.*}}
+#pragma float_control(precise, on)
+  float x = a * b + c;
+  //CHECK: fmuladd
+  return x;
+}

clang/test/CodeGen/fp-floatcontrol-stack.cpp

@@ -0,0 +1,253 @@
+// RUN: %clang_cc1 -triple x86_64-linux-gnu -ffp-contract=on -DDEFAULT=1 -emit-llvm -o - %s | FileCheck --check-prefix=CHECK-DDEFAULT %s
+// RUN: %clang_cc1 -triple x86_64-linux-gnu -ffp-contract=on -DEBSTRICT=1 -ffp-exception-behavior=strict -emit-llvm -o - %s | FileCheck --check-prefix=CHECK-DEBSTRICT %s
+// RUN: %clang_cc1 -triple x86_64-linux-gnu -DFAST=1 -ffast-math -ffp-contract=fast -emit-llvm -o - %s | FileCheck --check-prefix=CHECK-FAST %s
+// RUN: %clang_cc1 -triple x86_64-linux-gnu -ffp-contract=on -DNOHONOR=1 -menable-no-infs -menable-no-nans -emit-llvm -o - %s | FileCheck --check-prefix=CHECK-NOHONOR %s
+
+#define FUN(n) \
+  (float z) { return n * z + n; }
+
+float fun_default FUN(1)
+//CHECK-LABEL: define {{.*}} @_Z11fun_defaultf{{.*}}
+#if DEFAULT
+//CHECK-DDEFAULT: call contract float @llvm.fmuladd{{.*}}
+#endif
+#if EBSTRICT
+// Note that backend wants constrained intrinsics used
+// throughout the function if they are needed anywhere in the function.
+// In that case, operations are built with constrained intrinsics operator
+// but using default settings for exception behavior and rounding mode.
+//CHECK-DEBSTRICT: llvm.experimental.constrained.fmul{{.*}}tonearest{{.*}}strict
+#endif
+#if FAST
+//CHECK-FAST: fmul fast float
+//CHECK-FAST: fadd fast float
+#endif
+
+#pragma float_control(push)
+#ifndef FAST
+// Rule: precise must be enabled
+#pragma float_control(except, on)
+#endif
+    float exc_on FUN(2)
+//CHECK-LABEL: define {{.*}} @_Z6exc_onf{{.*}}
+#if DEFAULT
+//CHECK-DDEFAULT: llvm.experimental.constrained.fmul{{.*}}
+#endif
+#if EBSTRICT
+//CHECK-DEBSTRICT: llvm.experimental.constrained.fmuladd{{.*}}tonearest{{.*}}strict
+#endif
+#if NOHONOR
+//CHECK-NOHONOR: nnan ninf contract float {{.*}}llvm.experimental.constrained.fmuladd{{.*}}tonearest{{.*}}strict
+#endif
+#if FAST
+//Not possible to enable float_control(except) in FAST mode.
+//CHECK-FAST: fmul fast float
+//CHECK-FAST: fadd fast float
+#endif
+
+#pragma float_control(pop)
+        float exc_pop FUN(5)
+//CHECK-LABEL: define {{.*}} @_Z7exc_popf{{.*}}
+#if DEFAULT
+//CHECK-DDEFAULT: call contract float @llvm.fmuladd{{.*}}
+#endif
+#if EBSTRICT
+//CHECK-DEBSTRICT: llvm.experimental.constrained.fmuladd{{.*}}tonearest{{.*}}strict
+#endif
+#if NOHONOR
+//CHECK-NOHONOR: call nnan ninf contract float @llvm.fmuladd{{.*}}
+#endif
+#if FAST
+//CHECK-FAST: fmul fast float
+//CHECK-FAST: fadd fast float
+#endif
+
+#pragma float_control(except, off)
+            float exc_off FUN(5)
+//CHECK-LABEL: define {{.*}} @_Z7exc_offf{{.*}}
+#if DEFAULT
+//CHECK-DDEFAULT: call contract float @llvm.fmuladd{{.*}}
+#endif
+#if EBSTRICT
+//CHECK-DEBSTRICT: call contract float @llvm.fmuladd{{.*}}
+#endif
+#if NOHONOR
+//CHECK-NOHONOR: call nnan ninf contract float @llvm.fmuladd{{.*}}
+#endif
+#if FAST
+//CHECK-FAST: fmul fast float
+//CHECK-FAST: fadd fast float
+#endif
+
+#pragma float_control(precise, on, push)
+                float precise_on FUN(3)
+//CHECK-LABEL: define {{.*}} @_Z10precise_onf{{.*}}
+#if DEFAULT
+//CHECK-DDEFAULT: contract float {{.*}}llvm.fmuladd{{.*}}
+#endif
+#if EBSTRICT
+//CHECK-DEBSTRICT: contract float {{.*}}llvm.fmuladd{{.*}}
+#endif
+#if NOHONOR
+// If precise is pushed then all fast-math should be off!
+//CHECK-NOHONOR: call contract float {{.*}}llvm.fmuladd{{.*}}
+#endif
+#if FAST
+//CHECK-FAST: contract float {{.*}}llvm.fmuladd{{.*}}
+#endif
+
+#pragma float_control(pop)
+                    float precise_pop FUN(3)
+//CHECK-LABEL: define {{.*}} @_Z11precise_popf{{.*}}
+#if DEFAULT
+//CHECK-DDEFAULT: contract float {{.*}}llvm.fmuladd{{.*}}
+#endif
+#if EBSTRICT
+//CHECK-DEBSTRICT: contract float {{.*}}llvm.fmuladd{{.*}}
+#endif
+#if NOHONOR
+//CHECK-NOHONOR: call nnan ninf contract float @llvm.fmuladd{{.*}}
+#endif
+#if FAST
+//CHECK-FAST: fmul fast float
+//CHECK-FAST: fadd fast float
+#endif
+#pragma float_control(precise, off)
+                        float precise_off FUN(4)
+//CHECK-LABEL: define {{.*}} @_Z11precise_offf{{.*}}
+#if DEFAULT
+// Note: precise_off enables fp_contract=fast and the instructions
+// generated do not include the contract flag, although it was enabled
+// in IRBuilder.
+//CHECK-DDEFAULT: fmul fast float
+//CHECK-DDEFAULT: fadd fast float
+#endif
+#if EBSTRICT
+//CHECK-DEBSTRICT: fmul fast float
+//CHECK-DEBSTRICT: fadd fast float
+#endif
+#if NOHONOR
+// fast math should be enabled, and contract should be fast
+//CHECK-NOHONOR: fmul fast float
+//CHECK-NOHONOR: fadd fast float
+#endif
+#if FAST
+//CHECK-FAST: fmul fast float
+//CHECK-FAST: fadd fast float
+#endif
+
+#pragma float_control(precise, on)
+                            float precise_on2 FUN(3)
+//CHECK-LABEL: define {{.*}} @_Z11precise_on2f{{.*}}
+#if DEFAULT
+//CHECK-DDEFAULT: llvm.fmuladd{{.*}}
+#endif
+#if EBSTRICT
+//CHECK-DEBSTRICT: contract float {{.*}}llvm.fmuladd{{.*}}
+#endif
+#if NOHONOR
+// fast math should be off, and contract should be on
+//CHECK-NOHONOR: contract float {{.*}}llvm.fmuladd{{.*}}
+#endif
+#if FAST
+//CHECK-FAST: contract float {{.*}}llvm.fmuladd{{.*}}
+#endif
+
+#pragma float_control(push)
+                                float precise_push FUN(3)
+//CHECK-LABEL: define {{.*}} @_Z12precise_pushf{{.*}}
+#if DEFAULT
+//CHECK-DDEFAULT: llvm.fmuladd{{.*}}
+#endif
+#if EBSTRICT
+//CHECK-DEBSTRICT: contract float {{.*}}llvm.fmuladd{{.*}}
+#endif
+#if NOHONOR
+//CHECK-NOHONOR: contract float {{.*}}llvm.fmuladd{{.*}}
+#endif
+#if FAST
+//CHECK-FAST: contract float {{.*}}llvm.fmuladd{{.*}}
+#endif
+
+#pragma float_control(precise, off)
+                                    float precise_off2 FUN(4)
+//CHECK-LABEL: define {{.*}} @_Z12precise_off2f{{.*}}
+#if DEFAULT
+//CHECK-DDEFAULT: fmul fast float
+//CHECK-DDEFAULT: fadd fast float
+#endif
+#if EBSTRICT
+//CHECK-DEBSTRICT: fmul fast float
+//CHECK-DEBSTRICT: fadd fast float
+#endif
+#if NOHONOR
+// fast math settings since precise is off
+//CHECK-NOHONOR: fmul fast float
+//CHECK-NOHONOR: fadd fast float
+#endif
+#if FAST
+//CHECK-FAST: fmul fast float
+//CHECK-FAST: fadd fast float
+#endif
+
+#pragma float_control(pop)
+                                        float precise_pop2 FUN(3)
+//CHECK-LABEL: define {{.*}} @_Z12precise_pop2f{{.*}}
+#if DEFAULT
+//CHECK-DDEFAULT: llvm.fmuladd{{.*}}
+#endif
+#if EBSTRICT
+//CHECK-DEBSTRICT: contract float {{.*}}llvm.fmuladd{{.*}}
+#endif
+#if NOHONOR
+//CHECK-NOHONOR: contract float {{.*}}llvm.fmuladd{{.*}}
+#endif
+#if FAST
+//CHECK-FAST: contract float {{.*}}llvm.fmuladd{{.*}}
+#endif
+
+#ifndef FAST
+// Rule: precise must be enabled
+#pragma float_control(except, on)
+#endif
+                                            float y();
+class ON {
+  // Settings for top level class initializer revert to command line
+  // source pragma's do not pertain.
+  float z = 2 + y() * 7;
+//CHECK-LABEL: define {{.*}} void @_ZN2ONC2Ev{{.*}}
+#if DEFAULT
+//CHECK-DDEFAULT: call contract float {{.*}}llvm.fmuladd
+#endif
+#if EBSTRICT
+//Currently, same as default [command line options not considered]
+//CHECK-DEBSTRICT: call contract float {{.*}}llvm.fmuladd
+#endif
+#if NOHONOR
+//CHECK-NOHONOR: call nnan ninf contract float @llvm.fmuladd{{.*}}
+#endif
+#if FAST
+//CHECK-FAST: fmul fast float
+//CHECK-FAST: fadd fast float
+#endif
+};
+ON on;
+#pragma float_control(except, off)
+class OFF {
+  float w = 2 + y() * 7;
+//CHECK-LABEL: define {{.*}} void @_ZN3OFFC2Ev{{.*}}
+#if DEFAULT
+//CHECK-DDEFAULT: call contract float {{.*}}llvm.fmuladd
+#endif
+#if EBSTRICT
+//CHECK-DEBSTRICT: call contract float {{.*}}llvm.fmuladd
+#endif
+#if NOHONOR
+//CHECK-NOHONOR: call nnan ninf contract float @llvm.fmuladd{{.*}}
+#endif
+#if FAST
+//CHECK-FAST: fmul fast float
+//CHECK-FAST: fadd fast float
+#endif
+};
+OFF off;

clang/test/CodeGen/fpconstrained.c

@@ -1,7 +1,7 @@
 // RUN: %clang_cc1 -ftrapping-math -frounding-math -ffp-exception-behavior=strict -emit-llvm -o - %s | FileCheck %s -check-prefix=FPMODELSTRICT
 // RUN: %clang_cc1 -ffp-contract=fast -emit-llvm -o - %s | FileCheck %s -check-prefix=PRECISE
 // RUN: %clang_cc1 -ffast-math -ffp-contract=fast -emit-llvm -o - %s | FileCheck %s -check-prefix=FAST
-// RUN: %clang_cc1 -ffast-math -emit-llvm -o - %s | FileCheck %s -check-prefix=FAST
+// RUN: %clang_cc1 -ffast-math -emit-llvm -o - %s | FileCheck %s -check-prefix=FASTNOCONTRACT
 // RUN: %clang_cc1 -ffast-math -ffp-contract=fast -ffp-exception-behavior=ignore -emit-llvm -o - %s | FileCheck %s -check-prefix=FAST
 // RUN: %clang_cc1 -ffast-math -ffp-contract=fast -ffp-exception-behavior=strict -emit-llvm -o - %s | FileCheck %s -check-prefix=EXCEPT
 // RUN: %clang_cc1 -ffast-math -ffp-contract=fast -ffp-exception-behavior=maytrap -emit-llvm -o - %s | FileCheck %s -check-prefix=MAYTRAP
@@ -17,6 +17,7 @@ void foo() {
   // STRICTNOEXCEPT: llvm.experimental.constrained.fadd.f32(float %{{.*}}, float %{{.*}}, metadata !"round.dynamic", metadata !"fpexcept.ignore")
   // PRECISE: fadd contract float %{{.*}}, %{{.*}}
   // FAST: fadd fast
+  // FASTNOCONTRACT: fadd reassoc nnan ninf nsz arcp afn float
   f0 = f1 + f2;
 
   // CHECK: ret

clang/test/CodeGen/fpconstrained.cpp

@@ -1,7 +1,7 @@
 // RUN: %clang_cc1 -x c++ -ftrapping-math -fexceptions -fcxx-exceptions -frounding-math -ffp-exception-behavior=strict -emit-llvm -o - %s | FileCheck %s -check-prefix=FPMODELSTRICT
 // RUN: %clang_cc1 -x c++ -ffp-contract=fast -fexceptions -fcxx-exceptions -emit-llvm -o - %s | FileCheck %s -check-prefix=PRECISE
 // RUN: %clang_cc1 -x c++ -ffast-math -fexceptions -fcxx-exceptions -ffp-contract=fast -emit-llvm -o - %s | FileCheck %s -check-prefix=FAST
-// RUN: %clang_cc1 -x c++ -ffast-math -fexceptions -fcxx-exceptions -emit-llvm -o - %s | FileCheck %s -check-prefix=FAST
+// RUN: %clang_cc1 -x c++ -ffast-math -fexceptions -fcxx-exceptions -emit-llvm -o - %s | FileCheck %s -check-prefix=FASTNOCONTRACT
 // RUN: %clang_cc1 -x c++ -ffast-math -fexceptions -fcxx-exceptions -ffp-contract=fast -ffp-exception-behavior=ignore -emit-llvm -o - %s | FileCheck %s -check-prefix=FAST
 // RUN: %clang_cc1 -x c++ -ffast-math -fexceptions -fcxx-exceptions -ffp-contract=fast -ffp-exception-behavior=strict -emit-llvm -o - %s | FileCheck %s -check-prefix=EXCEPT
 // RUN: %clang_cc1 -x c++ -ffast-math -fexceptions -fcxx-exceptions -ffp-contract=fast -ffp-exception-behavior=maytrap -emit-llvm -o - %s | FileCheck %s -check-prefix=MAYTRAP
@@ -20,16 +20,17 @@ float f0, f1, f2;
   // CHECK-LABEL: define {{.*}}void @_ZN4aaaaIiED2Ev{{.*}}
 
   } catch (...) {
-  // MAYTRAP: llvm.experimental.constrained.fadd.f32(float %{{.*}}, float %{{.*}}, metadata !"round.tonearest", metadata !"fpexcept.maytrap")
+    // MAYTRAP: llvm.experimental.constrained.fadd.f32(float %{{.*}}, float %{{.*}}, metadata !"round.tonearest", metadata !"fpexcept.maytrap")
-  // EXCEPT: llvm.experimental.constrained.fadd.f32(float %{{.*}}, float %{{.*}}, metadata !"round.tonearest", metadata !"fpexcept.strict")
+    // EXCEPT: llvm.experimental.constrained.fadd.f32(float %{{.*}}, float %{{.*}}, metadata !"round.tonearest", metadata !"fpexcept.strict")
-  // FPMODELSTRICT: llvm.experimental.constrained.fadd.f32(float %{{.*}}, float %{{.*}}, metadata !"round.dynamic", metadata !"fpexcept.strict")
+    // FPMODELSTRICT: llvm.experimental.constrained.fadd.f32(float %{{.*}}, float %{{.*}}, metadata !"round.dynamic", metadata !"fpexcept.strict")
-  // STRICTEXCEPT: llvm.experimental.constrained.fadd.f32(float %{{.*}}, float %{{.*}}, metadata !"round.dynamic", metadata !"fpexcept.strict")
+    // STRICTEXCEPT: llvm.experimental.constrained.fadd.f32(float %{{.*}}, float %{{.*}}, metadata !"round.dynamic", metadata !"fpexcept.strict")
-  // STRICTNOEXCEPT: llvm.experimental.constrained.fadd.f32(float %{{.*}}, float %{{.*}}, metadata !"round.dynamic", metadata !"fpexcept.ignore")
+    // STRICTNOEXCEPT: llvm.experimental.constrained.fadd.f32(float %{{.*}}, float %{{.*}}, metadata !"round.dynamic", metadata !"fpexcept.ignore")
-  // PRECISE: fadd contract float %{{.*}}, %{{.*}}
+    // PRECISE: fadd contract float %{{.*}}, %{{.*}}
-  // FAST: fadd fast
+    // FAST: fadd fast
-  f0 = f1 + f2;
+    // FASTNOCONTRACT: fadd reassoc nnan ninf nsz arcp afn float
+    f0 = f1 + f2;
 
-  // CHECK: ret void
+    // CHECK: ret void
   }
   }
   

clang/test/CodeGenOpenCL/relaxed-fpmath.cl

@@ -8,12 +8,12 @@
 float spscalardiv(float a, float b) {
   // CHECK: @spscalardiv(
 
-  // NORMAL: fdiv float
+  // NORMAL: fdiv contract float
   // FAST: fdiv fast float
-  // FINITE: fdiv nnan ninf float
+  // FINITE: fdiv nnan ninf contract float
-  // UNSAFE: fdiv nnan nsz float
+  // UNSAFE: fdiv nnan nsz contract float
-  // MAD: fdiv float
+  // MAD: fdiv contract float
-  // NOSIGNED: fdiv nsz float
+  // NOSIGNED: fdiv nsz contract float
   return a / b;
 }
 // CHECK: attributes

clang/test/CodeGenOpenCL/single-precision-constant.cl

@@ -1,6 +1,6 @@
 // RUN: %clang_cc1 %s -cl-single-precision-constant -emit-llvm -o - | FileCheck %s
 
 float fn(float f) {
-  // CHECK: tail call float @llvm.fmuladd.f32(float %f, float 2.000000e+00, float 1.000000e+00)
+  // CHECK: tail call contract float @llvm.fmuladd.f32(float %f, float 2.000000e+00, float 1.000000e+00)
   return f*2. + 1.;
 }

clang/test/Headers/nvptx_device_math_sin.c

@@ -1,8 +1,8 @@
 // REQUIRES: nvptx-registered-target
 // RUN: %clang_cc1 -x c -internal-isystem %S/Inputs/include -fopenmp -triple powerpc64le-unknown-unknown -fopenmp-targets=nvptx64-nvidia-cuda -emit-llvm-bc %s -o %t-ppc-host.bc
 // RUN: %clang_cc1 -x c -include __clang_openmp_device_functions.h -internal-isystem %S/../../lib/Headers/openmp_wrappers -internal-isystem %S/Inputs/include -fopenmp -triple nvptx64-nvidia-cuda -aux-triple powerpc64le-unknown-unknown -fopenmp-targets=nvptx64-nvidia-cuda -emit-llvm %s -fopenmp-is-device -fopenmp-host-ir-file-path %t-ppc-host.bc -o - | FileCheck %s --check-prefix=SLOW
-// RUN: %clang_cc1 -x c -internal-isystem %S/Inputs/include -fopenmp -triple powerpc64le-unknown-unknown -fopenmp-targets=nvptx64-nvidia-cuda -emit-llvm-bc %s -o %t-ppc-host.bc -ffast-math
+// RUN: %clang_cc1 -x c -internal-isystem %S/Inputs/include -fopenmp -triple powerpc64le-unknown-unknown -fopenmp-targets=nvptx64-nvidia-cuda -emit-llvm-bc %s -o %t-ppc-host.bc -ffast-math -ffp-contract=fast
-// RUN: %clang_cc1 -x c -include __clang_openmp_device_functions.h -internal-isystem %S/../../lib/Headers/openmp_wrappers -internal-isystem %S/Inputs/include -fopenmp -triple nvptx64-nvidia-cuda -aux-triple powerpc64le-unknown-unknown -fopenmp-targets=nvptx64-nvidia-cuda -emit-llvm %s -fopenmp-is-device -fopenmp-host-ir-file-path %t-ppc-host.bc -o - -ffast-math | FileCheck %s --check-prefix=FAST
+// RUN: %clang_cc1 -x c -include __clang_openmp_device_functions.h -internal-isystem %S/../../lib/Headers/openmp_wrappers -internal-isystem %S/Inputs/include -fopenmp -triple nvptx64-nvidia-cuda -aux-triple powerpc64le-unknown-unknown -fopenmp-targets=nvptx64-nvidia-cuda -emit-llvm %s -fopenmp-is-device -fopenmp-host-ir-file-path %t-ppc-host.bc -o - -ffast-math -ffp-contract=fast | FileCheck %s --check-prefix=FAST
 // expected-no-diagnostics
 
 #include <math.h>

clang/test/Headers/nvptx_device_math_sin.cpp

@@ -1,8 +1,8 @@
 // REQUIRES: nvptx-registered-target
 // RUN: %clang_cc1 -x c++ -internal-isystem %S/Inputs/include -fopenmp -triple powerpc64le-unknown-unknown -fopenmp-targets=nvptx64-nvidia-cuda -emit-llvm-bc %s -o %t-ppc-host.bc
 // RUN: %clang_cc1 -x c++ -include __clang_openmp_device_functions.h -internal-isystem %S/../../lib/Headers/openmp_wrappers -internal-isystem %S/Inputs/include -fopenmp -triple nvptx64-nvidia-cuda -aux-triple powerpc64le-unknown-unknown -fopenmp-targets=nvptx64-nvidia-cuda -emit-llvm %s -fopenmp-is-device -fopenmp-host-ir-file-path %t-ppc-host.bc -o - | FileCheck %s --check-prefix=SLOW
-// RUN: %clang_cc1 -x c++ -internal-isystem %S/Inputs/include -fopenmp -triple powerpc64le-unknown-unknown -fopenmp-targets=nvptx64-nvidia-cuda -emit-llvm-bc %s -o %t-ppc-host.bc -ffast-math
+// RUN: %clang_cc1 -x c++ -internal-isystem %S/Inputs/include -fopenmp -triple powerpc64le-unknown-unknown -fopenmp-targets=nvptx64-nvidia-cuda -emit-llvm-bc %s -o %t-ppc-host.bc -ffast-math -ffp-contract=fast
-// RUN: %clang_cc1 -x c++ -include __clang_openmp_device_functions.h -internal-isystem %S/../../lib/Headers/openmp_wrappers -internal-isystem %S/Inputs/include -fopenmp -triple nvptx64-nvidia-cuda -aux-triple powerpc64le-unknown-unknown -fopenmp-targets=nvptx64-nvidia-cuda -emit-llvm %s -fopenmp-is-device -fopenmp-host-ir-file-path %t-ppc-host.bc -o - -ffast-math | FileCheck %s --check-prefix=FAST
+// RUN: %clang_cc1 -x c++ -include __clang_openmp_device_functions.h -internal-isystem %S/../../lib/Headers/openmp_wrappers -internal-isystem %S/Inputs/include -fopenmp -triple nvptx64-nvidia-cuda -aux-triple powerpc64le-unknown-unknown -fopenmp-targets=nvptx64-nvidia-cuda -emit-llvm %s -fopenmp-is-device -fopenmp-host-ir-file-path %t-ppc-host.bc -o - -ffast-math -ffp-contract=fast | FileCheck %s --check-prefix=FAST
 // expected-no-diagnostics
 
 #include <cmath>

clang/test/PCH/pragma-floatcontrol.c

@@ -0,0 +1,55 @@
+// Test this without pch.
+// RUN: %clang_cc1 %s -include %s -verify -fsyntax-only -DSET
+// RUN: %clang_cc1 %s -include %s -verify -fsyntax-only -DPUSH
+// RUN: %clang_cc1 %s -include %s -verify -fsyntax-only -DPUSH_POP
+
+// Test with pch.
+// RUN: %clang_cc1 %s -DSET -emit-pch -o %t
+// RUN: %clang_cc1 %s -DSET -include-pch %t -emit-llvm -o - | FileCheck --check-prefix=CHECK-EBSTRICT %s
+// RUN: %clang_cc1 %s -DPUSH -emit-pch -o %t
+// RUN: %clang_cc1 %s -DPUSH -verify -include-pch %t
+// RUN: %clang_cc1 %s -DPUSH_POP -emit-pch -o %t
+// RUN: %clang_cc1 %s -DPUSH_POP -verify -include-pch %t
+
+#ifndef HEADER
+#define HEADER
+
+#ifdef SET
+#pragma float_control(except, on)
+#endif
+
+#ifdef PUSH
+#pragma float_control(precise, on)
+#pragma float_control(push)
+#pragma float_control(precise, off)
+#endif
+
+#ifdef PUSH_POP
+#pragma float_control(precise, on, push)
+#pragma float_control(push)
+#pragma float_control(pop)
+#endif
+#else
+
+#ifdef SET
+float fun(float a, float b) {
+  // CHECK-LABEL: define float @fun{{.*}}
+  //CHECK-EBSTRICT: llvm.experimental.constrained.fmul{{.*}}tonearest{{.*}}strict
+  //CHECK-EBSTRICT: llvm.experimental.constrained.fadd{{.*}}tonearest{{.*}}strict
+  return a * b + 2;
+}
+#pragma float_control(pop) // expected-warning {{#pragma float_control(pop, ...) failed: stack empty}}
+#pragma float_control(pop) // expected-warning {{#pragma float_control(pop, ...) failed: stack empty}}
+#endif
+
+#ifdef PUSH
+#pragma float_control(pop)
+#pragma float_control(pop) // expected-warning {{#pragma float_control(pop, ...) failed: stack empty}}
+#endif
+
+#ifdef PUSH_POP
+#pragma float_control(pop)
+#pragma float_control(pop) // expected-warning {{#pragma float_control(pop, ...) failed: stack empty}}
+#endif
+
+#endif //ifndef HEADER

clang/test/Parser/fp-floatcontrol-syntax.cpp

@@ -0,0 +1,60 @@
+// RUN: %clang_cc1 -triple x86_64-linux-gnu -fsyntax-only -DCHECK_ERROR %s -verify 
+
+float function_scope(float a) {
+#pragma float_control(precise, on) junk // expected-warning {{extra tokens at end of '#pragma float_control' - ignored}}
+  return a;
+}
+
+#ifdef CHECK_ERROR
+#pragma float_control(push)
+#pragma float_control(pop)
+#pragma float_control(precise, on, push)
+void check_stack() {
+#pragma float_control(push)                   // expected-error {{can only appear at file scope}}
+#pragma float_control(pop)                    // expected-error {{can only appear at file scope}}
+#pragma float_control(precise, on, push)      // expected-error {{can only appear at file scope}}
+#pragma float_control(except, on, push)       // expected-error {{can only appear at file scope}}
+#pragma float_control(except, on, push, junk) // expected-error {{float_control is malformed}}
+  return;
+}
+#endif
+
+// RUN: %clang_cc1 -triple x86_64-linux-gnu -fdenormal-fp-math=preserve-sign,preserve-sign -ftrapping-math -fsyntax-only %s -DDEFAULT -verify
+// RUN: %clang_cc1 -triple x86_64-linux-gnu -fsyntax-only %s -ffp-contract=fast -DPRECISE -verify
+// RUN: %clang_cc1 -triple x86_64-linux-gnu -fsyntax-only %s -ftrapping-math -ffp-contract=off -frounding-math -ffp-exception-behavior=strict -DSTRICT -verify
+// RUN: %clang_cc1 -triple x86_64-linux-gnu -menable-no-infs -menable-no-nans -menable-unsafe-fp-math -fno-signed-zeros -mreassociate -freciprocal-math -ffp-contract=fast -ffast-math -ffinite-math-only -fsyntax-only %s -DFAST -verify
+double a = 0.0;
+double b = 1.0;
+
+//FIXME At some point this warning will be removed, until then
+//      document the warning
+#ifdef FAST
+// expected-warning@+1{{pragma STDC FENV_ACCESS ON is not supported, ignoring pragma}}
+#pragma STDC FENV_ACCESS ON // expected-error{{'#pragma STDC FENV_ACCESS ON' is illegal when precise is disabled}}
+#else
+#pragma STDC FENV_ACCESS ON // expected-warning{{pragma STDC FENV_ACCESS ON is not supported, ignoring pragma}}
+#endif
+#ifdef STRICT
+#pragma float_control(precise, off) // expected-error {{'#pragma float_control(precise, off)' is illegal when except is enabled}}
+#else
+#pragma float_control(precise, off) // expected-error {{'#pragma float_control(precise, off)' is illegal when fenv_access is enabled}}
+#endif
+
+#pragma float_control(precise, on)
+#pragma float_control(except, on) // OK
+#ifndef STRICT
+#pragma float_control(except, on)
+#pragma float_control(precise, off) // expected-error {{'#pragma float_control(precise, off)' is illegal when except is enabled}}
+#endif
+int main() {
+#ifdef STRICT
+#pragma float_control(precise, off) // expected-error {{'#pragma float_control(precise, off)' is illegal when except is enabled}}
+#else
+#pragma float_control(precise, off) // expected-error {{'#pragma float_control(precise, off)' is illegal when except is enabled}}
+#endif
+#pragma float_control(except, on)
+  //  error: '#pragma float_control(except, on)' is illegal when precise is disabled
+  double x = b / a; // only used for fp flag setting
+  if (a == a)       // only used for fp flag setting
+    return 0;       //(int)x;
+}

llvm/include/llvm/IR/IRBuilder.h

@@ -244,6 +244,8 @@ public:
   /// Get the flags to be applied to created floating point ops
   FastMathFlags getFastMathFlags() const { return FMF; }
 
+  FastMathFlags &getFastMathFlags() { return FMF; }
+
   /// Clear the fast-math flags.
   void clearFastMathFlags() { FMF.clear(); }
 
@@ -332,10 +334,16 @@ public:
     IRBuilderBase &Builder;
     FastMathFlags FMF;
     MDNode *FPMathTag;
+    bool IsFPConstrained;
+    fp::ExceptionBehavior DefaultConstrainedExcept;
+    RoundingMode DefaultConstrainedRounding;
 
   public:
     FastMathFlagGuard(IRBuilderBase &B)
-        : Builder(B), FMF(B.FMF), FPMathTag(B.DefaultFPMathTag) {}
+        : Builder(B), FMF(B.FMF), FPMathTag(B.DefaultFPMathTag),
+          IsFPConstrained(B.IsFPConstrained),
+          DefaultConstrainedExcept(B.DefaultConstrainedExcept),
+          DefaultConstrainedRounding(B.DefaultConstrainedRounding) {}
 
     FastMathFlagGuard(const FastMathFlagGuard &) = delete;
     FastMathFlagGuard &operator=(const FastMathFlagGuard &) = delete;
@@ -343,6 +351,9 @@ public:
     ~FastMathFlagGuard() {
       Builder.FMF = FMF;
       Builder.DefaultFPMathTag = FPMathTag;
+      Builder.IsFPConstrained = IsFPConstrained;
+      Builder.DefaultConstrainedExcept = DefaultConstrainedExcept;
+      Builder.DefaultConstrainedRounding = DefaultConstrainedRounding;
     }
   };