[SYCL][FE][Driver] Implement floating point accuracy control

clang/include/clang/Basic/CodeGenOptions.def

@@ -373,6 +373,10 @@ CODEGENOPT(VirtualFunctionElimination, 1, 0) ///< Whether to apply the dead
                                              /// virtual function elimination
                                              /// optimization.
 
+/// Whether accuracy levels for math library functions are requested by the
+/// user. These accuracy levels will then be expressed in terms of ULPs.
+CODEGENOPT(FPAccuracy, 1, 0)
+
 /// Whether to use public LTO visibility for entities in std and stdext
 /// namespaces. This is enabled by clang-cl's /MT and /MTd flags.
 CODEGENOPT(LTOVisibilityPublicStd, 1, 0)

clang/include/clang/Basic/DiagnosticCommonKinds.td

@@ -301,6 +301,9 @@ def warn_stack_clash_protection_inline_asm : Warning<
 def warn_slh_does_not_support_asm_goto : Warning<
   "speculative load hardening does not protect functions with asm goto">,
   InGroup<DiagGroup<"slh-asm-goto">>;
+
+def err_drv_incompatible_options : Error<
+  "the combination of '%0' and '%1' is incompatible">;
 }
 
 // Sema && Serialization

clang/include/clang/Basic/DiagnosticDriverKinds.td

@@ -63,6 +63,10 @@ def err_drv_no_cuda_libdevice : Error<
   "via '--cuda-path', or pass '-nocudalib' to build without linking with "
   "libdevice">;
 
+def warn_function_fp_accuracy_already_set : Warning <
+  "floating point accuracy value of '%0' has already been assigned to "
+  "function '%1'">,
+  InGroup<DiagGroup<"fp-accuracy-already-set">>;
 def err_drv_no_rocm_device_lib : Error<
   "cannot find ROCm device library%select{| for %1|for ABI version %1}0; provide its path via "
   "'--rocm-path' or '--rocm-device-lib-path', or pass '-nogpulib' to build "
@@ -141,8 +145,9 @@ def err_drv_invalid_unwindlib_name : Error<
   "invalid unwind library name in argument '%0'">;
 def err_drv_incompatible_unwindlib : Error<
   "--rtlib=libgcc requires --unwindlib=libgcc">;
-def err_drv_incompatible_options : Error<
-  "the combination of '%0' and '%1' is incompatible">;
+def err_drv_incompatible_fp_accuracy_options : Error<
+  "floating point accuracy requirements cannot be guaranteed when '-fmath-errno' "
+  "is enabled; use '-fno-math-errno' to enable floating point accuracy control">;
 def err_drv_invalid_stdlib_name : Error<
   "invalid library name in argument '%0'">;
 def err_drv_invalid_output_with_multiple_archs : Error<

clang/include/clang/Basic/FPOptions.def

@@ -26,5 +26,6 @@ OPTION(AllowReciprocal, bool, 1, NoSignedZero)
 OPTION(AllowApproxFunc, bool, 1, AllowReciprocal)
 OPTION(FPEvalMethod, LangOptions::FPEvalMethodKind, 2, AllowApproxFunc)
 OPTION(Float16ExcessPrecision, LangOptions::ExcessPrecisionKind, 2, FPEvalMethod)
-OPTION(BFloat16ExcessPrecision, LangOptions::ExcessPrecisionKind, 2, FPEvalMethod)
+OPTION(BFloat16ExcessPrecision, LangOptions::ExcessPrecisionKind, 2, Float16ExcessPrecision)
+OPTION(FPAccuracy, LangOptions::FPAccuracyKind, 3, BFloat16ExcessPrecision)
 #undef OPTION

clang/include/clang/Basic/LangOptions.def

@@ -338,6 +338,7 @@ BENIGN_ENUM_LANGOPT(FPExceptionMode, FPExceptionModeKind, 2, FPE_Default, "FP Ex
 BENIGN_ENUM_LANGOPT(FPEvalMethod, FPEvalMethodKind, 2, FEM_UnsetOnCommandLine, "FP type used for floating point arithmetic")
 ENUM_LANGOPT(Float16ExcessPrecision, ExcessPrecisionKind, 2, FPP_Standard, "Intermediate truncation behavior for Float16 arithmetic")
 ENUM_LANGOPT(BFloat16ExcessPrecision, ExcessPrecisionKind, 2, FPP_Standard, "Intermediate truncation behavior for BFloat16 arithmetic")
+BENIGN_ENUM_LANGOPT(FPAccuracy, FPAccuracyKind, 3, FPA_Default, "Accuracy for floating point operations and library functions")
 LANGOPT(NoBitFieldTypeAlign , 1, 0, "bit-field type alignment")
 LANGOPT(HexagonQdsp6Compat , 1, 0, "hexagon-qdsp6 backward compatibility")
 LANGOPT(ObjCAutoRefCount , 1, 0, "Objective-C automated reference counting")

clang/include/clang/Basic/LangOptions.h

@@ -303,6 +303,15 @@ class LangOptions : public LangOptionsBase {
 
   enum ExcessPrecisionKind { FPP_Standard, FPP_Fast, FPP_None };
 
+  enum FPAccuracyKind {
+    FPA_Default,
+    FPA_High,
+    FPA_Medium,
+    FPA_Low,
+    FPA_Sycl,
+    FPA_Cuda,
+  };
+
   /// Possible exception handling behavior.
   enum class ExceptionHandlingKind { None, SjLj, WinEH, DwarfCFI, Wasm };
 
@@ -509,6 +518,10 @@ class LangOptions : public LangOptionsBase {
   /// records.
   std::string OptRecordFile;
 
+  std::string FPAccuracyVal;
+  using FPAccuracyFuncMapTy = std::map<std::string, std::string>;
+  FPAccuracyFuncMapTy FPAccuracyFuncMap;
+
   LangOptions();
 
   /// Set language defaults for the given input language and

clang/include/clang/Driver/Options.td

@@ -1729,6 +1729,13 @@ def ffp_exception_behavior_EQ : Joined<["-"], "ffp-exception-behavior=">, Group<
   Values<"ignore,maytrap,strict">, NormalizedValuesScope<"LangOptions">,
   NormalizedValues<["FPE_Ignore", "FPE_MayTrap", "FPE_Strict"]>,
   MarshallingInfoEnum<LangOpts<"FPExceptionMode">, "FPE_Default">;
+def ffp_accuracy_EQ : Joined<["-"], "ffp-accuracy=">, Group<f_Group>, Flags<[CC1Option]>,
+  HelpText<"Specifies the required accuracy for floating-point operations and library calls.">,
+  Values<"default,high,medium,low,sycl,cuda">, NormalizedValuesScope<"LangOptions">,
+  NormalizedValues<["FPA_Default", "FPA_High", "FPA_Medium", "FPA_Low", "FPA_Sycl", "FPA_Cuda"]>,
+  MarshallingInfoEnum<LangOpts<"FPAccuracy">, "FPA_Default">;
+def ffp_builtin_accuracy_EQ : Joined<["-"], "ffp-builtin-accuracy=">, Group<f_Group>, Flags<[CC1Option]>;
+
 defm fast_math : BoolFOption<"fast-math",
   LangOpts<"FastMath">, DefaultFalse,
   PosFlag<SetTrue, [CC1Option, CoreOption, FC1Option, FlangOption], "Allow aggressive, lossy floating-point optimizations",
@@ -7020,6 +7027,14 @@ class CLRemainingArgsJoined<string name> : Option<["/", "-"], name,
 // (We don't put any of these in cl_compile_Group as the options they alias are
 // already in the right group.)
 
+// INTEL_CUSTOMIZATION
+def _SLASH_Qfp_accuracy_EQ : CLJoined<"Qfp-accuracy=">,
+  Alias<ffp_accuracy_EQ>;
+def _SLASH_Qfp_accuracy_COL : CLJoined<"Qfp-accuracy:">,
+  Alias<ffp_accuracy_EQ>,HelpText<"Specifies the required accuracy for "
+  "floating-point operations and library calls.">;
+// END INTEL_CUSTOMIZATION
+
 def _SLASH_Brepro : CLFlag<"Brepro">,
   HelpText<"Do not write current time into COFF output (breaks link.exe /incremental)">,
   Alias<mno_incremental_linker_compatible>;

clang/include/clang/Frontend/CompilerInvocation.h

@@ -276,6 +276,9 @@ class CompilerInvocation : public CompilerInvocationRefBase,
                             std::vector<std::string> &Includes,
                             DiagnosticsEngine &Diags);
 
+  static void ParseFpAccuracyArgs(LangOptions &Opts, llvm::opt::ArgList &Args,
+                                  DiagnosticsEngine &Diags);
+
   /// Generate command line options from LangOptions.
   static void GenerateLangArgs(const LangOptions &Opts,
                                SmallVectorImpl<const char *> &Args,