SPNU151V January   1998  – February 2020

 

  1.   Read This First
    1.     About This Manual
    2.     Notational Conventions
    3.     Related Documentation
    4.     Related Documentation From Texas Instruments
    5.     Trademarks
  2. 1Introduction to the Software Development Tools
    1. 1.1 Software Development Tools Overview
    2. 1.2 Compiler Interface
    3. 1.3 ANSI/ISO Standard
    4. 1.4 Output Files
    5. 1.5 Utilities
  3. 2Using the C/C++ Compiler
    1. 2.1  About the Compiler
    2. 2.2  Invoking the C/C++ Compiler
    3. 2.3  Changing the Compiler's Behavior with Options
      1. 2.3.1  Linker Options
      2. 2.3.2  Frequently Used Options
      3. 2.3.3  Miscellaneous Useful Options
      4. 2.3.4  Run-Time Model Options
      5. 2.3.5  Symbolic Debugging and Profiling Options
      6. 2.3.6  Specifying Filenames
      7. 2.3.7  Changing How the Compiler Interprets Filenames
      8. 2.3.8  Changing How the Compiler Processes C Files
      9. 2.3.9  Changing How the Compiler Interprets and Names Extensions
      10. 2.3.10 Specifying Directories
      11. 2.3.11 Assembler Options
      12. 2.3.12 Deprecated Options
    4. 2.4  Controlling the Compiler Through Environment Variables
      1. 2.4.1 Setting Default Compiler Options (TI_ARM_C_OPTION)
      2. 2.4.2 Naming One or More Alternate Directories (TI_ARM_C_DIR)
    5. 2.5  Controlling the Preprocessor
      1. 2.5.1  Predefined Macro Names
      2. 2.5.2  The Search Path for #include Files
        1. 2.5.2.1 Adding a Directory to the #include File Search Path (--include_path Option)
      3. 2.5.3  Support for the #warning and #warn Directives
      4. 2.5.4  Generating a Preprocessed Listing File (--preproc_only Option)
      5. 2.5.5  Continuing Compilation After Preprocessing (--preproc_with_compile Option)
      6. 2.5.6  Generating a Preprocessed Listing File with Comments (--preproc_with_comment Option)
      7. 2.5.7  Generating Preprocessed Listing with Line-Control Details (--preproc_with_line Option)
      8. 2.5.8  Generating Preprocessed Output for a Make Utility (--preproc_dependency Option)
      9. 2.5.9  Generating a List of Files Included with #include (--preproc_includes Option)
      10. 2.5.10 Generating a List of Macros in a File (--preproc_macros Option)
    6. 2.6  Passing Arguments to main()
    7. 2.7  Understanding Diagnostic Messages
      1. 2.7.1 Controlling Diagnostic Messages
      2. 2.7.2 How You Can Use Diagnostic Suppression Options
    8. 2.8  Other Messages
    9. 2.9  Generating Cross-Reference Listing Information (--gen_cross_reference Option)
    10. 2.10 Generating a Raw Listing File (--gen_preprocessor_listing Option)
    11. 2.11 Using Inline Function Expansion
      1. 2.11.1 Inlining Intrinsic Operators
      2. 2.11.2 Inlining Restrictions
    12. 2.12 Using Interlist
      1.      Example 1. An Interlisted Assembly Language File
    13. 2.13 Controlling Application Binary Interface
    14. 2.14 VFP Support
    15. 2.15 Enabling Entry Hook and Exit Hook Functions
  4. 3Optimizing Your Code
    1. 3.1  Invoking Optimization
    2. 3.2  Controlling Code Size Versus Speed
    3. 3.3  Performing File-Level Optimization (--opt_level=3 option)
      1. 3.3.1 Creating an Optimization Information File (--gen_opt_info Option)
    4. 3.4  Program-Level Optimization (--program_level_compile and --opt_level=3 options)
      1. 3.4.1 Controlling Program-Level Optimization (--call_assumptions Option)
      2. 3.4.2 Optimization Considerations When Mixing C/C++ and Assembly
    5. 3.5  Automatic Inline Expansion (--auto_inline Option)
    6. 3.6  Link-Time Optimization (--opt_level=4 Option)
      1. 3.6.1 Option Handling
      2. 3.6.2 Incompatible Types
    7. 3.7  Using Feedback Directed Optimization
      1. 3.7.1 Feedback Directed Optimization
        1. 3.7.1.1 Phase 1 -- Collect Program Profile Information
        2. 3.7.1.2 Phase 2 -- Use Application Profile Information for Optimization
        3. 3.7.1.3 Generating and Using Profile Information
        4. 3.7.1.4 Example Use of Feedback Directed Optimization
        5. 3.7.1.5 The .ppdata Section
        6. 3.7.1.6 Feedback Directed Optimization and Code Size Tune
        7. 3.7.1.7 Instrumented Program Execution Overhead
        8. 3.7.1.8 Invalid Profile Data
      2. 3.7.2 Profile Data Decoder
      3. 3.7.3 Feedback Directed Optimization API
      4. 3.7.4 Feedback Directed Optimization Summary
    8. 3.8  Using Profile Information to Analyze Code Coverage
      1. 3.8.1 Code Coverage
        1. 3.8.1.1 Phase1 -- Collect Program Profile Information
        2. 3.8.1.2 Phase 2 -- Generate Code Coverage Reports
      2. 3.8.2 Related Features and Capabilities
        1. 3.8.2.1 Path Profiler
        2. 3.8.2.2 Analysis Options
        3. 3.8.2.3 Environment Variables
    9. 3.9  Accessing Aliased Variables in Optimized Code
    10. 3.10 Use Caution With asm Statements in Optimized Code
    11. 3.11 Using the Interlist Feature With Optimization
      1.      Example 1. The Function From Compiled With the -O2 and --optimizer_interlist Options
      2.      Example 2. The Function From Compiled with the --opt_level=2, --optimizer_interlist, and --c_src_interlist Options
    12. 3.12 Debugging and Profiling Optimized Code
      1. 3.12.1 Profiling Optimized Code
    13. 3.13 What Kind of Optimization Is Being Performed?
      1. 3.13.1  Cost-Based Register Allocation
      2. 3.13.2  Alias Disambiguation
      3. 3.13.3  Branch Optimizations and Control-Flow Simplification
      4. 3.13.4  Data Flow Optimizations
      5. 3.13.5  Expression Simplification
      6. 3.13.6  Inline Expansion of Functions
      7. 3.13.7  Function Symbol Aliasing
      8. 3.13.8  Induction Variables and Strength Reduction
      9. 3.13.9  Loop-Invariant Code Motion
      10. 3.13.10 Loop Rotation
      11. 3.13.11 Instruction Scheduling
      12. 3.13.12 Tail Merging
      13. 3.13.13 Autoincrement Addressing
      14. 3.13.14 Block Conditionalizing
        1.       Example 3. Block Conditionalizing C Source
        2.       Example 4. C/C++ Compiler Output for
      15. 3.13.15 Epilog Inlining
      16. 3.13.16 Removing Comparisons to Zero
      17. 3.13.17 Integer Division With Constant Divisor
      18. 3.13.18 Branch Chaining
  5. 4Linking C/C++ Code
    1. 4.1 Invoking the Linker Through the Compiler (-z Option)
      1. 4.1.1 Invoking the Linker Separately
      2. 4.1.2 Invoking the Linker as Part of the Compile Step
      3. 4.1.3 Disabling the Linker (--compile_only Compiler Option)
    2. 4.2 Linker Code Optimizations
      1. 4.2.1 Generate List of Dead Functions (--generate_dead_funcs_list Option)
      2. 4.2.2 Generating Aggregate Data Subsections (--gen_data_subsections Compiler Option)
    3. 4.3 Controlling the Linking Process
      1. 4.3.1 Including the Run-Time-Support Library
        1. 4.3.1.1 Automatic Run-Time-Support Library Selection
          1.        Example 1. Using the --issue_remarks Option
        2. 4.3.1.2 Manual Run-Time-Support Library Selection
        3. 4.3.1.3 Library Order for Searching for Symbols
      2. 4.3.2 Run-Time Initialization
      3. 4.3.3 Initialization of Cinit and Watchdog Timer Hold
      4. 4.3.4 Global Object Constructors
      5. 4.3.5 Specifying the Type of Global Variable Initialization
      6. 4.3.6 Specifying Where to Allocate Sections in Memory
      7. 4.3.7 A Sample Linker Command File
        1.       Example 2. Linker Command File
  6. 5C/C++ Language Implementation
    1. 5.1  Characteristics of ARM C
      1. 5.1.1 Implementation-Defined Behavior
    2. 5.2  Characteristics of ARM C++
    3. 5.3  Using MISRA C 2004
    4. 5.4  Using the ULP Advisor
    5. 5.5  Data Types
      1. 5.5.1 Size of Enum Types
    6. 5.6  File Encodings and Character Sets
    7. 5.7  Keywords
      1. 5.7.1 The const Keyword
      2. 5.7.2 The __interrupt Keyword
      3. 5.7.3 The volatile Keyword
        1.       Example 1. Volatile for Local Variables With setjmp
    8. 5.8  C++ Exception Handling
    9. 5.9  Register Variables and Parameters
      1. 5.9.1 Local Register Variables and Parameters
      2. 5.9.2 Global Register Variables
    10. 5.10 The __asm Statement
    11. 5.11 Pragma Directives
      1. 5.11.1  The CALLS Pragma
      2. 5.11.2  The CHECK_MISRA Pragma
      3. 5.11.3  The CHECK_ULP Pragma
      4. 5.11.4  The CODE_ALIGN Pragma
      5. 5.11.5  The CODE_SECTION Pragma
        1.       Example 2. Using the CODE_SECTION Pragma C Source File
        2.       Example 3. Generated Assembly Code From
      6. 5.11.6  The CODE_STATE Pragma
      7. 5.11.7  The DATA_ALIGN Pragma
      8. 5.11.8  The DATA_SECTION Pragma
        1.       Example 4. Using the DATA_SECTION Pragma C Source File
        2.       Example 5. Using the DATA_SECTION Pragma C++ Source File
        3.       Example 6. Using the DATA_SECTION Pragma Assembly Source File
      9. 5.11.9  The Diagnostic Message Pragmas
      10. 5.11.10 The DUAL_STATE Pragma
      11. 5.11.11 The FORCEINLINE Pragma
      12. 5.11.12 The FORCEINLINE_RECURSIVE Pragma
      13. 5.11.13 The FUNC_ALWAYS_INLINE Pragma
      14. 5.11.14 The FUNC_CANNOT_INLINE Pragma
      15. 5.11.15 The FUNC_EXT_CALLED Pragma
      16. 5.11.16 The FUNCTION_OPTIONS Pragma
      17. 5.11.17 The INTERRUPT Pragma
      18. 5.11.18 The LOCATION Pragma
      19. 5.11.19 The MUST_ITERATE Pragma
        1. 5.11.19.1 The MUST_ITERATE Pragma Syntax
        2. 5.11.19.2 Using MUST_ITERATE to Expand Compiler Knowledge of Loops
      20. 5.11.20 The NOINIT and PERSISTENT Pragmas
      21. 5.11.21 The NOINLINE Pragma
      22. 5.11.22 The NO_HOOKS Pragma
      23. 5.11.23 The once Pragma
      24. 5.11.24 The pack Pragma
      25. 5.11.25 The RESET_MISRA Pragma
      26. 5.11.26 The RESET_ULP Pragma
      27. 5.11.27 The RETAIN Pragma
      28. 5.11.28 The SET_CODE_SECTION and SET_DATA_SECTION Pragmas
        1.       Example 7. Setting Section With SET_DATA_SECTION Pragma
        2.       Example 8. Setting a Section With SET_CODE_SECTION Pragma
        3.       Example 9. Overriding SET_DATA_SECTION Setting
      29. 5.11.29 The SWI_ALIAS Pragma
        1.       Example 10. Using the SWI_ALIAS Pragma C Source File
        2.       Example 11. Generated Assembly File
      30. 5.11.30 The TASK Pragma
      31. 5.11.31 The UNROLL Pragma
      32. 5.11.32 The WEAK Pragma
    12. 5.12 The _Pragma Operator
    13. 5.13 Application Binary Interface
    14. 5.14 ARM Instruction Intrinsics
    15. 5.15 Object File Symbol Naming Conventions (Linknames)
    16. 5.16 Changing the ANSI/ISO C/C++ Language Mode
      1. 5.16.1 C99 Support (--c99)
      2. 5.16.2 C11 Support (--c11)
      3. 5.16.3 Strict ANSI Mode and Relaxed ANSI Mode (--strict_ansi and --relaxed_ansi)
    17. 5.17 GNU, Clang, and ACLE Language Extensions
      1. 5.17.1 Extensions
      2. 5.17.2 Function Attributes
      3. 5.17.3 Variable Attributes
      4. 5.17.4 Type Attributes
      5. 5.17.5 Built-In Functions
    18. 5.18 AUTOSAR
    19. 5.19 Compiler Limits
  7. 6Run-Time Environment
    1. 6.1  Memory Model
      1. 6.1.1 Sections
      2. 6.1.2 C/C++ System Stack
      3. 6.1.3 Dynamic Memory Allocation
    2. 6.2  Object Representation
      1. 6.2.1 Data Type Storage
        1. 6.2.1.1 char and short Data Types (signed and unsigned)
        2. 6.2.1.2 float, int, and long Data Types (signed and unsigned)
        3. 6.2.1.3 double, long double, and long long Data Types (signed and unsigned)
        4. 6.2.1.4 Pointer to Data Member Types
        5. 6.2.1.5 Pointer to Member Function Types
        6. 6.2.1.6 Structure and Array Alignment
      2. 6.2.2 Bit Fields
      3. 6.2.3 Character String Constants
    3. 6.3  Register Conventions
    4. 6.4  Function Structure and Calling Conventions
      1. 6.4.1 How a Function Makes a Call
      2. 6.4.2 How a Called Function Responds
      3. 6.4.3 C Exception Handler Calling Convention
      4. 6.4.4 Accessing Arguments and Local Variables
    5. 6.5  Accessing Linker Symbols in C and C++
    6. 6.6  Interfacing C and C++ With Assembly Language
      1. 6.6.1 Using Assembly Language Modules With C/C++ Code
      2. 6.6.2 Accessing Assembly Language Functions From C/C++
        1.       Example 1. Calling an Assembly Language Function From a C/C++ Program
        2.       Example 2. Assembly Language Program Called by
      3. 6.6.3 Accessing Assembly Language Variables From C/C++
        1. 6.6.3.1 Accessing Assembly Language Global Variables
          1.        Example 3. Assembly Language Variable Program
          2.        Example 4. C Program to Access Assembly Language From
        2. 6.6.3.2 Accessing Assembly Language Constants
          1.        Example 5. Accessing an Assembly Language Constant From C
          2.        Example 6. Assembly Language Program for
      4. 6.6.4 Sharing C/C++ Header Files With Assembly Source
      5. 6.6.5 Using Inline Assembly Language
      6. 6.6.6 Modifying Compiler Output
    7. 6.7  Interrupt Handling
      1. 6.7.1 Saving Registers During Interrupts
      2. 6.7.2 Using C/C++ Interrupt Routines
      3. 6.7.3 Using Assembly Language Interrupt Routines
      4. 6.7.4 How to Map Interrupt Routines to Interrupt Vectors
        1.       Example 7. Sample intvecs.asm File
      5. 6.7.5 Using Software Interrupts
      6. 6.7.6 Other Interrupt Information
    8. 6.8  Intrinsic Run-Time-Support Arithmetic and Conversion Routines
      1. 6.8.1 CPSR Register and Interrupt Intrinsics
    9. 6.9  Built-In Functions
    10. 6.10 System Initialization
      1. 6.10.1 Boot Hook Functions for System Pre-Initialization
      2. 6.10.2 Run-Time Stack
      3. 6.10.3 Automatic Initialization of Variables
        1. 6.10.3.1 Zero Initializing Variables
        2. 6.10.3.2 Direct Initialization
        3. 6.10.3.3 Autoinitialization of Variables at Run Time
        4. 6.10.3.4 Autoinitialization Tables
          1. 6.10.3.4.1 Length Followed by Data Format
          2. 6.10.3.4.2 Zero Initialization Format
          3. 6.10.3.4.3 Run Length Encoded (RLE) Format
          4. 6.10.3.4.4 Lempel-Ziv-Storer-Szymanski Compression (LZSS) Format
          5. 6.10.3.4.5 Sample C Code to Process the C Autoinitialization Table
            1.         Example 8. Processing the C Autoinitialization Table
        5. 6.10.3.5 Initialization of Variables at Load Time
        6. 6.10.3.6 Global Constructors
      4. 6.10.4 Initialization Tables
        1.       Example 9. Initialized Variables Defined in C
        2.       Example 10. Initialized Information for Variables Defined in
    11. 6.11 Dual-State Interworking Under TIABI (Deprecated)
      1. 6.11.1 Level of Dual-State Support
      2. 6.11.2 Implementation
        1. 6.11.2.1 Naming Conventions for Entry Points
        2. 6.11.2.2 Indirect Calls
          1.        Example 11. C Code Compiled for 16-BIS State: sum( )
          2.        Example 12. 16-Bit Assembly Program for
          3.        Example 13. C Code Compiled for 32-BIS State: sum( )
          4.        Example 14. 32-Bit Assembly Program for
  8. 7Using Run-Time-Support Functions and Building Libraries
    1. 7.1 C and C++ Run-Time Support Libraries
      1. 7.1.1 Linking Code With the Object Library
      2. 7.1.2 Header Files
      3. 7.1.3 Modifying a Library Function
      4. 7.1.4 Support for String Handling
      5. 7.1.5 Minimal Support for Internationalization
      6. 7.1.6 Allowable Number of Open Files
      7. 7.1.7 Nonstandard Header Files in the Source Tree
      8. 7.1.8 Library Naming Conventions
    2. 7.2 The C I/O Functions
      1. 7.2.1 High-Level I/O Functions
        1. 7.2.1.1 Formatting and the Format Conversion Buffer
      2. 7.2.2 Overview of Low-Level I/O Implementation
      3. 7.2.3 Device-Driver Level I/O Functions
      4. 7.2.4 Adding a User-Defined Device Driver for C I/O
        1.       Example 1. Mapping Default Streams to Device
      5. 7.2.5 The device Prefix
        1.       Example 2. Program for C I/O Device
    3. 7.3 Handling Reentrancy (_register_lock() and _register_unlock() Functions)
    4. 7.4 Library-Build Process
      1. 7.4.1 Required Non-Texas Instruments Software
      2. 7.4.2 Using the Library-Build Process
        1. 7.4.2.1 Automatic Standard Library Rebuilding by the Linker
        2. 7.4.2.2 Invoking mklib Manually
          1. 7.4.2.2.1 Building Standard Libraries
          2. 7.4.2.2.2 Shared or Read-Only Library Directory
          3. 7.4.2.2.3 Building Libraries With Custom Options
          4. 7.4.2.2.4 The mklib Program Option Summary
      3. 7.4.3 Extending mklib
        1. 7.4.3.1 Underlying Mechanism
        2. 7.4.3.2 Libraries From Other Vendors
  9. 8C++ Name Demangler
    1. 8.1 Invoking the C++ Name Demangler
    2. 8.2 Sample Usage of the C++ Name Demangler
      1.      Example 1. C++ Code for calories_in_a_banana
      2.      Example 2. Resulting Assembly for calories_in_a_banana
      3.      Example 3. Result After Running the C++ Name Demangler
  10.   A Glossary
    1.     A.1 Terminology
  11.   B Revision History
    1.     B.1 Recent Revisions

2.5.1 Predefined Macro Names

The compiler maintains and recognizes the predefined macro names listed in Table 2-30.

Table 2-30 Predefined ARM Macro Names

Macro Name Description
__16bis__ Defined if 16-BIS state is selected (the -code_state=16 option is used); otherwise, it is undefined.
__32bis__ Defined if 32-BIS state is selected (the -code_state=16 option is not used); otherwise, it is undefined.
_AEABI_PORTABILITY_LEVEL Define to 1 to enable full object file portability when headers files are included. Define to 0 to require full C standard compatibility. See the ARM standard for details.
__DATE__(1) Expands to the compilation date in the form mmm dd yyyy
__FILE__(1) Expands to the current source filename
__LINE__(1) Expands to the current line number
__signed_chars__ Defined if char types are signed by default
__STDC__(1) Defined to 1 to indicate that compiler conforms to ISO C Standard. See Section 5.1 for exceptions to ISO C conformance.
__STDC_VERSION__ C standard macro.
__STDC_HOSTED__ C standard macro. Always defined to 1.
__STDC_NO_THREADS__ C standard macro. Always defined to 1.
__TI_COMPILER_VERSION__ Defined to a 7-9 digit integer, depending on if X has 1, 2, or 3 digits. The number does not contain a decimal. For example, version 3.2.1 is represented as 3002001. The leading zeros are dropped to prevent the number being interpreted as an octal.
__TI_EABI_SUPPORT__ Defined to 1 if the EABI ABI is enabled (this is the default); otherwise, it is undefined.
__TI_FPALIB_SUPPORT__ Defined to 1 if the FPA endianness is used to store double-precision floating-point values; otherwise, it is undefined.
__TI_GNU_ATTRIBUTE_SUPPORT__ Defined to 1 if GCC extensions are enabled (which is the default)
__TI_NEON_SUPPORT__ Defined to 1 if NEON SIMD extension is targeted (the --neon option is used); otherwise, it is undefined.
__TI_STRICT_ANSI_MODE__ Defined to 1 if strict ANSI/ISO mode is enabled (the --strict_ansi option is used); otherwise, it is defined as 0.
__TI_STRICT_FP_MODE__ Defined to 1 if --fp_mode=strict is used (default); otherwise, it is defined as 0.
__TI_ ARM_V4__ Defined to 1 if the v4 architecture (ARM7) is targeted (the -mv4 option is used); otherwise, it is undefined.
__TI_ ARM_V5__ Defined to 1 if the v5E architecture (ARM9E) is targeted (the -mv5e option is used); otherwise, it is undefined.
__TI_ ARM_V6__ Defined to 1 if the v6 architecture (ARM11) is targeted (the -mv6 option is used); otherwise, it is undefined.
__TI_ ARM_V6M0__ Defined to 1 if the v6M0 architecture (Cortex-M0) is targeted (the -mv6M0 option is used); otherwise, it is undefined.
__TI_ ARM_V7__ Defined to 1 if any v7 architecture (Cortex) is targeted; otherwise, it is undefined.
__TI_ ARM_V7A8__ Defined to 1 if the v7A8 architecture (Cortex-A8) is targeted (the -mv7A8 option is used); otherwise, it is undefined.
__TI_ ARM_V7M3__ Defined to 1 if the v7M3 architecture (Cortex-M3) is targeted (the -mv7M3 option is used); otherwise, it is undefined.
__TI_ ARM_V7M4__ Defined to 1 if the v7M4 architecture (Cortex-M4) is targeted (the -mv7M4 option is used); otherwise, it is undefined.
__TI_ ARM_V7R4__ Defined to 1 if the v7R4 architecture (Cortex-R4) is targeted (the -mv7R4 option is used); otherwise, it is undefined.
__TI_ ARM_V7R5__ Defined to 1 if the v7R5 architecture (Cortex-R5) is targeted (the -mv7R5 option is used); otherwise, it is undefined.
__TI_VFP_SUPPORT__ Defined to 1 if the VFP coprocessor is enabled (any --float_support option is used); otherwise, it is undefined.
__TI_VFPLIB_SUPPORT__ Defined to 1 if the VFP endianness is used to store double-precision floating-point values; otherwise, it is undefined.
__TI_VFPV3_SUPPORT__ Defined to 1 if the VFP coprocessor is enabled (the --float_support=vfpv3 option is used); otherwise, it is undefined.
__TI_VFPV3D16_SUPPORT__ Defined to 1 if the VFP coprocessor is enabled (the --float_support=vfpv3d16 option is used); otherwise, it is undefined.
__TI_FPV4SPD16_SUPPORT__ Defined to 1 if the VFP coprocessor is enabled (the --float_support=fpv4spd16 option is used); otherwise, it is undefined.
__TI_WCHAR_T_BITS__ Set to the type of wchar_t.
__TIME__(1) Expands to the compilation time in the form "hh:mm:ss"
__TI_ ARM__ Always defined
__unsigned_chars__ Defined if char types are unsigned by default (default)
__big_endian__ Defined if big-endian mode is selected (the --endian=big option is used or the --endian=little option is not used); otherwise, it is undefined.
__WCHAR_T_TYPE__ Set to the type of wchar_t.
_INLINE Expands to 1 if optimization is used (--opt_level or -O option); undefined otherwise.
__little_endian__ Defined if little-endian mode is selected (the --endian=little option is used); otherwise, it is undefined.
(1) Specified by the ISO standard

NOTE

Macros with names that contain __TI_ARM are duplicates of the older __TI_TMS470 macros. For example, __TI_ARM_V7__ is the newer name for the __TI_TMS470_V7__ macro. The old macro names still exist and can continue to be used.

You can use the names listed in Table 2-30 in the same manner as any other defined name. For example,

printf ( "%s %s" , __TIME__ , __DATE__);

translates to a line such as:

printf ("%s %s" , "13:58:17", "Jan 14 1997");

In addition, the ARM C Language Extensions (ACLE) v2.0 specification describes macros that identify features of the ARM architecture and how the C/C++ implementation uses the architecture. All ACLE predefined macros begin with the prefix __ARM. Table 2-31 lists the macros mentioned in the ACLE specification and the section of the specification that provides more information. Some macros are undefined because they are not applicable for any Cortex-M or Cortex-R processor variant.

Table 2-31 ACLE Pre-Defined Macros

Macro Name Description Section in ACLE Specification
__ARM_32BIT_STATE Defined as 1 if the compiler is generating code for an ARM 32-bit processor variant (-mv6m0, -mv7m3, -mv7m4, -mv7a8, -mv7r4, and -mv7r5); undefined otherwise. (Section 5.4.1)
__ARM_64BIT_STATE Undefined (Section 5.4.1)
__ARM_ACLE Defined as 200 for all Cortex-M and Cortex-R processor variants (-mv6m0, -mv7m3, -mv7m4, -mv7r4, and -mv7r5). (Sections 3.4, 5.2)
__ARM_ALIGN_MAX_PWR Not supported (Section 6.5.2)
__ARM_ALIGN_MAX_STACK_PWR Not supported (Section 6.5.3)
__ARM_ARCH Identifies the version of ARM architecture selected on the compiler command line.
  • 4 indicates -mv4
  • 5 indicates -mv5e
  • 6 indicates -mv6 or -mv6m0
  • 7 indicates -mv7a8, -mv7m3, -mv7m4, -mv7r4, or -mv7r5
(Section 5.1)
__ARM_ARCH_ISA_A64 Undefined (Section 5.4.1)
__ARM_ARCH_ISA_ARM Defined as 1 if the compiler is generating code for a processor variant that supports the ARM instruction set (-mv7a8, -mv7r4, and -mv7r5); undefined otherwise. (Section 5.4.1)
__ARM_ARCH_ISA_THUMB Defined as 1 if the compiler is generating code for a processor variant that supports the THUMB-1 instruction set. Defined as 2 if the compiler is generating code for a processor variant that supports the THUMB-2 instruction set; undefined otherwise. (Section 5.4.1)
__ARM_ARCH_PROFILE Not supported (Section 5.4.2)
__ARM_BIG_ENDIAN Defined as 1 by default; not defined if --little-endian (-me) option is used. (Section 5.3)
__ARM_FEATURE_CLZ Defined as 1 if the compiler is generating code for a processor variant that supports the CLZ instruction (-mv7m3, -mv7m4, -mv7a8, -mv7r4, and -mv7r5); undefined otherwise. (Section 5.4.5)
__ARM_FEATURE_COPROC Not supported (Section 5.9)
__ARM_FEATURE_CRC32 Undefined (Section 5.5.8)
__ARM_FEATURE_CRYPTO Undefined (Section 5.5.7)
__ARM_FEATURE_DIRECTED_ROUNDING Undefined (Section 5.5.9)
__ARM_FEATURE_DSP Defined as 1 if the compiler is generating code for a Cortex-M or Cortex-R processor that supports DSP instructions/intrinsics (-mv7m4, -mv7r4, and -mv7r5); undefined otherwise. (Section 5.4.7)
__ARM_FEATURE_FMA Not supported (Section 5.5.3)
__ARM_FEATURE_FP16_SCALAR_ ARITHMETIC Undefined (Sections 3.4, 5.5.13)
__ARM_FEATURE_FP16_VECTOR_ ARITHMETIC Undefined (Section 5.5.13)
__ARM_FEATURE_IDIV Not supported (Section 5.4.10)
__ARM_FEATURE_JCVT Undefined (Section 5.5.14)
__ARM_FEATURE_LDREX Undefined (Section 5.4.4)
__ARM_FEATURE_NUMERIC_MAXMIN Undefined (Section 5.5.10)
__ARM_FEATURE_QBIT Not supported (Section 5.4.6)
__ARM_FEATURE_QRDMX Undefined (Section 5.5.12)
__ARM_FEATURE_SAT Defined as 1 if the compiler is generating code for a processor variant that supports SSAT/USAT instructions/intrinsics (-mv7m3, -mv7m4, -mv7a8, -mv7r4, and -mv7r5); undefined otherwise. (Section 5.4.8)
__ARM_FEATURE_SIMD32 Defined as 1 if the compiler is generating code for a processor variant that supports all SIMD instructions/intrinsics (-mv7m4, -mv7r4, and -mv7r5); undefined otherwise. (Section 5.4.9)
__ARM_FEATURE_UNALIGNED Defined as 1 if the compiler is generating code for a processor variant that supports unaligned access to memory (-mv7m3, -mv7m4, -mv7a8, -mv7r4, and -mv7r5); undefined otherwise. (Section 5.4.3)
__ARM_FP Defined as 6 for --float_support={fpv4spd16 | fpv5spd16}. Defined as 12 for --float_support={vfpv2 | vfpv3 | vfpv3d16}; undefined otherwise. (Section 5.5.1)
__ARM_FP16_ARGS Defined as 1 if a 16-bit float type can be used for an argument and/or result; undefined otherwise. (Section 5.5.11)
__ARM_FP16_FORMAT_ALTERNATIVE Undefined (Section 5.5.2)
__ARM_FP16_FORMAT_IEEE Defined as 1 if the IEEE format for 16-bit floating-point (according to IEEE 754-2008 standard) is used; undefined otherwise. (Section 5.5.2)
__ARM_FP_FAST Not supported (Section 5.6)
__ARM_FP_FENV_ROUNDING Not supported (Section 5.6)
__ARM_NEON Undefined (Sections 3.4, 5.5.4)
__ARM_NEON_FP Undefined (Section 5.5.5)
__ARM_PCS Defined as 1 if the compiler can assume the default procedure calling standard for a translation unit conforms to the "base procedure call standard" as prescribed in the ARM Architecture Procedure Call Standard (AAPCS) specification (-mv7m3, -mv7m4, -mv7r4, and -mv7r5); undefined otherwise. (Section 5.7)
__ARM_PCS_AAPCS64 Undefined (Section 5.7)
__ARM_PCS_VFP Defined as 1 if the default procedure calling convention is to pass floating-point arguments / return values in hardware floating-point registers; undefined otherwise. (Section 5.7)
__ARM_ROPI Undefined (Section 5.8)
__ARM_RWPI Undefined (Section 5.8)
__ARM_SIZEOF_MINIMAL_ENUM Defined to the smallest possible enum type size (1 byte for packed, 4 bytes for int). This mirrors the --enum_type=[packed | int] option where packed is the default. (Section 3.1.1)
__ARM_SIZEOF_WCHAR_T Defined as 2 if --wchar_t=16 (default). Defined as 4 if --wchar_t=32. (Section 3.1.1)
__ARM_WMMX Undefined (Section 5.5.6)
__STDC_IEC_559__ Undefined (Section 5.6)
__SUPPORT_SNAN__ Not supported (Section 5.6)