| //===- subzero/src/IceBuildDefs.h - Translator build defines ----*- C++ -*-===// |
| // |
| // The Subzero Code Generator |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| /// |
| /// \file |
| /// \brief Define the Ice::BuildDefs namespace |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef SUBZERO_SRC_ICEBUILDDEFS_H |
| #define SUBZERO_SRC_ICEBUILDDEFS_H |
| |
| namespace Ice { |
| /// \brief Defines constexpr functions that express various Subzero build |
| /// system defined values. |
| /// |
| /// These resulting constexpr functions allow code to in effect be |
| /// conditionally compiled without having to do this using the older C++ |
| /// preprocessor solution. |
| |
| /** \verbatim |
| |
| For example whenever the value of FEATURE_SUPPORTED is needed, instead |
| of (except in these constexpr functions): |
| |
| #if FEATURE_SUPPORTED ... |
| ... |
| #endif |
| |
| We can have: |
| |
| namespace Ice { |
| namespace BuildDefs { |
| |
| // Use this form when FEATURE_SUPPORTED is guaranteed to be defined on the |
| // C++ compiler command line as 0 or 1. |
| constexpr bool hasFeature() { return FEATURE_SUPPORTED; } |
| |
| or |
| |
| // Use this form when FEATURE_SUPPORTED may not necessarily be defined on |
| // the C++ compiler command line. |
| constexpr bool hasFeature() { |
| #if FEATURE_SUPPORTED |
| return true; |
| #else // !FEATURE_SUPPORTED |
| return false; |
| #endif // !FEATURE_SUPPORTED |
| } |
| |
| ...} // end of namespace BuildDefs |
| } // end of namespace Ice |
| |
| |
| And later in the code: |
| |
| if (Ice::BuildDefs::hasFeature() { |
| ... |
| } |
| |
| \endverbatim |
| |
| Since hasFeature() returns a constexpr, an optimizing compiler will know to |
| keep or discard the above fragment. In addition, the code will always be |
| looked at by the compiler which eliminates the problem with defines in that |
| if you don't build that variant, you don't even know if the code would |
| compile unless you build with that variant. |
| |
| **/ |
| |
| namespace BuildDefs { |
| |
| // The ALLOW_* etc. symbols must be #defined to zero or non-zero. |
| /// Return true if ALLOW_DUMP is defined as a non-zero value |
| constexpr bool dump() { return ALLOW_DUMP; } |
| /// Return true if ALLOW_TIMERS is defined as a non-zero value |
| constexpr bool timers() { return ALLOW_TIMERS; } |
| /// Return true if ALLOW_LLVM_CL is defined as a non-zero value |
| // TODO(stichnot): this ALLOW_LLVM_CL is a TBD option which will |
| // allow for replacement of llvm:cl command line processor with a |
| // smaller footprint version for Subzero. |
| constexpr bool llvmCl() { return ALLOW_LLVM_CL; } |
| /// Return true if ALLOW_LLVM_IR is defined as a non-zero value |
| constexpr bool llvmIr() { return ALLOW_LLVM_IR; } |
| /// Return true if ALLOW_LLVM_IR_AS_INPUT is defined as a non-zero value |
| constexpr bool llvmIrAsInput() { return ALLOW_LLVM_IR_AS_INPUT; } |
| /// Return true if ALLOW_MINIMAL_BUILD is defined as a non-zero value |
| constexpr bool minimal() { return ALLOW_MINIMAL_BUILD; } |
| /// Return true if ALLOW_WASM is defined as a non-zero value |
| constexpr bool wasm() { return ALLOW_WASM; } |
| |
| /// Return true if NDEBUG is defined |
| constexpr bool asserts() { |
| #ifdef NDEBUG |
| return false; |
| #else // !NDEBUG |
| return true; |
| #endif // !NDEBUG |
| } |
| |
| /// Return true if PNACL_BROWSER_TRANSLATOR is defined |
| constexpr bool browser() { |
| #if PNACL_BROWSER_TRANSLATOR |
| return true; |
| #else // !PNACL_BROWSER_TRANSLATOR |
| return false; |
| #endif // !PNACL_BROWSER_TRANSLATOR |
| } |
| |
| /// Return true if ALLOW_EXTRA_VALIDATION is defined |
| constexpr bool extraValidation() { |
| #if ALLOW_EXTRA_VALIDATION |
| return true; |
| #else // !ALLOW_EXTRA_VALIDATION |
| return false; |
| #endif // !ALLOW_EXTRA_VALIDATION |
| } |
| |
| } // end of namespace BuildDefs |
| } // end of namespace Ice |
| |
| #endif // SUBZERO_SRC_ICEBUILDDEFS_H |