SPRAC71A March   2019  – February 2020

1. 1 Introduction
   1. 1.1  ABIs for the C28x
   2. 1.2  Scope
   3. 1.3  ABI Variants
   4. 1.4  Toolchains and Interoperability
   5. 1.5  Libraries
   6. 1.6  Types of Object Files
   7. 1.7  Segments
   8. 1.8  C28x Architecture Overview
   9. 1.9  C28x Memory Models
   10. 1.10 Reference Documents
   11. 1.11 Code Fragment Notation
2. 2 Data Representation
   1. 2.1 Basic Types
   2. 2.2 Data in Registers
   3. 2.3 Data in Memory
   4. 2.4 Pointer Types
   5. 2.5 Complex Types
   6. 2.6 Structures and Unions
   7. 2.7 Arrays
   8. 2.8 Bit Fields
      1. 2.8.1 Volatile Bit Fields
   9. 2.9 Enumeration Types
3. 3 Calling Conventions
   1. 3.1 Call and Return
      1. 3.1.1 Call Instructions
         1. 3.1.1.1 Indirect Calls
         2. 3.1.1.2 Direct Calls
      2. 3.1.2 Return Instruction
      3. 3.1.3 Pipeline Conventions
      4. 3.1.4 Weak Functions
   2. 3.2 Register Conventions
      1. 3.2.1 Argument Registers
      2. 3.2.2 Callee-Saved Registers
   3. 3.3 Argument Passing
      1. 3.3.1 Passing 16-Bit Arguments
      2. 3.3.2 Passing Longer Arguments
      3. 3.3.3 C++ Argument Passing
      4. 3.3.4 Passing Structs and Unions
      5. 3.3.5 Stack Layout of Arguments Not Passed in Registers
      6. 3.3.6 Frame Pointer
   4. 3.4 Return Values
   5. 3.5 Structures and Unions Passed and Returned by Reference
   6. 3.6 Conventions for Compiler Helper Functions
   7. 3.7 Prolog and Epilog Helper Functions
   8. 3.8 Scratch Registers for Functions Already Seen
   9. 3.9 Interrupt Functions
4. 4 Data Allocation and Addressing
   1. 4.1 Data Sections and Segments
   2. 4.2 Data Blocking
   3. 4.3 Addressing Modes
   4. 4.4 Allocation and Addressing of Static Data
      1. 4.4.1 Addressing Methods for Static Data
      2. 4.4.2 Placement Conventions for Static Data
         1. 4.4.2.1 Abstract Conventions for Addressing
      3. 4.4.3 Initialization of Static Data
   5. 4.5 Automatic Variables
   6. 4.6 Frame Layout
      1. 4.6.1 Stack Alignment
      2. 4.6.2 Register Save Order
   7. 4.7 Heap-Allocated Objects
5. 5 Code Allocation and Addressing
   1. 5.1 Computing the Address of a Code Label
   2. 5.2 Calls
      1. 5.2.1 Direct Call
      2. 5.2.2 Far Call Trampoline
      3. 5.2.3 Indirect Calls
6. 6 Helper Function API
   1. 6.1 Floating-Point Behavior
   2. 6.2 C Helper Function API
   3. 6.3 Floating-Point Helper Functions for C99
7. 7 Standard C Library API
   1. 7.1  About Standard C Libraries
   2. 7.2  Reserved Symbols
   3. 7.3  <assert.h> Implementation
   4. 7.4  <complex.h> Implementation
   5. 7.5  <ctype.h> Implementation
   6. 7.6  <errno.h> Implementation
   7. 7.7  <float.h> Implementation
   8. 7.8  <inttypes.h> Implementation
   9. 7.9  <iso646.h> Implementation
   10. 7.10 <limits.h> Implementation
   11. 7.11 <locale.h> Implementation
   12. 7.12 <math.h> Implementation
   13. 7.13 <setjmp.h> Implementation
   14. 7.14 <signal.h> Implementation
   15. 7.15 <stdarg.h> Implementation
   16. 7.16 <stdbool.h> Implementation
   17. 7.17 <stddef.h> Implementation
   18. 7.18 <stdint.h> Implementation
   19. 7.19 <stdio.h> Implementation
   20. 7.20 <stdlib.h> Implementation
   21. 7.21 <string.h> Implementation
   22. 7.22 <tgmath.h> Implementation
   23. 7.23 <time.h> Implementation
   24. 7.24 <wchar.h> Implementation
   25. 7.25 <wctype.h> Implementation
8. 8 C++ ABI
   1. 8.1  Limits (GC++ABI 1.2)
   2. 8.2  Export Template (GC++ABI 1.4.2)
   3. 8.3  Data Layout (GC++ABI Chapter 2)
   4. 8.4  Initialization Guard Variables (GC++ABI 2.8)
   5. 8.5  Constructor Return Value (GC++ABI 3.1.5)
   6. 8.6  One-Time Construction API (GC++ABI 3.3.2)
   7. 8.7  Controlling Object Construction Order (GC++ ABI 3.3.4)
   8. 8.8  Demangler API (GC++ABI 3.4)
   9. 8.9  Static Data (GC++ ABI 5.2.2)
   10. 8.10 Virtual Tables and the Key function (GC++ABI 5.2.3)
   11. 8.11 Unwind Table Location (GC++ABI 5.3)
9. 9 Exception Handling
   1. 9.1  Overview
   2. 9.2  PREL31 Encoding
   3. 9.3  The Exception Index Table (EXIDX)
      1. 9.3.1 Pointer to Out-of-Line EXTAB Entry
      2. 9.3.2 EXIDX_CANTUNWIND
      3. 9.3.3 Inlined EXTAB Entry
   4. 9.4  The Exception Handling Instruction Table (EXTAB)
      1. 9.4.1 EXTAB Generic Model
      2. 9.4.2 EXTAB Compact Model
      3. 9.4.3 Personality Routines
   5. 9.5  Unwinding Instructions
      1. 9.5.1 Common Sequence
      2. 9.5.2 Byte-Encoded Unwinding Instructions
   6. 9.6  Descriptors
      1. 9.6.1 Encoding of Type Identifiers
      2. 9.6.2 Scope
      3. 9.6.3 Cleanup Descriptor
      4. 9.6.4 Catch Descriptor
      5. 9.6.5 Function Exception Specification (FESPEC) Descriptor
   7. 9.7  Special Sections
   8. 9.8  Interaction With Non-C++ Code
      1. 9.8.1 Automatic EXIDX Entry Generation
      2. 9.8.2 Hand-Coded Assembly Functions
   9. 9.9  Interaction With System Features
      1. 9.9.1 Shared Libraries
      2. 9.9.2 Overlays
      3. 9.9.3 Interrupts
   10. 9.10 Assembly Language Operators in the TI Toolchain
10. 10DWARF
    1. 10.1 DWARF Register Names
    2. 10.2 Call Frame Information
    3. 10.3 Vendor Names
    4. 10.4 Vendor Extensions
11. 11ELF Object Files (Processor Supplement)
    1. 11.1 Registered Vendor Names
    2. 11.2 ELF Header
    3. 11.3 Sections
       1. 11.3.1 Section Indexes
       2. 11.3.2 Section Types
       3. 11.3.3 Extended Section Header Attributes
       4. 11.3.4 Subsections
       5. 11.3.5 Special Sections
       6. 11.3.6 Section Alignment
    4. 11.4 Symbol Table
       1. 11.4.1 Symbol Types
       2. 11.4.2 Common Block Symbols
       3. 11.4.3 Symbol Names
       4. 11.4.4 Reserved Symbol Names
       5. 11.4.5 Mapping Symbols
    5. 11.5 Relocation
       1. 11.5.1 Relocation Types
          1. 11.5.1.1 Absolute Relocations
          2. 11.5.1.2 PC-Relative Relocations
          3. 11.5.1.3 Relocations in Data Sections
          4. 11.5.1.4 Relocations for C28x Instructions
          5. 11.5.1.5 Other Relocation Types
       2. 11.5.2 Relocation Operations
       3. 11.5.3 Relocation of Unresolved Weak References
12. 12ELF Program Loading and Linking (Processor Supplement)
    1. 12.1 Program Header
       1. 12.1.1 Base Address
       2. 12.1.2 Segment Contents
       3. 12.1.3 Thread-Local Storage
    2. 12.2 Program Loading
13. 13Build Attributes
    1. 13.1 About Build Attributes
    2. 13.2 C28x ABI Build Attribute Subsection
    3. 13.3 C28x Build Attribute Tags
14. 14Copy Tables and Variable Initialization
    1. 14.1 About Copy Tables
    2. 14.2 Copy Table Format
    3. 14.3 Compressed Data Formats
       1. 14.3.1 RLE
       2. 14.3.2 LZSS Format
    4. 14.4 Variable Initialization
15. 15Revision History

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