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(a) The FSF's Front-Cover Text is:
A GNU Manual
(b) The FSF's Back-Cover Text is:
You have freedom to copy and modify this GNU Manual, like GNU software. Copies published by the Free Software Foundation raise funds for GNU development.
Short Contents
- Introduction
- 1 Contributing to GCC Development
- 2 GCC and Portability
- 3 Interfacing to GCC Output
- 4 The GCC low-level runtime library
- 5 Language Front Ends in GCC
- 6 Source Tree Structure and Build System
- 7 Option specification files
- 8 Passes and Files of the Compiler
- 9 Trees: The intermediate representation used by the C and C++ front ends
- 10 Analysis and Optimization of GIMPLE Trees
- 11 Analysis and Representation of Loops
- 12 RTL Representation
- 13 Control Flow Graph
- 14 Machine Descriptions
- 15 Target Description Macros and Functions
- 16 Host Configuration
- 17 Makefile Fragments
- 18
collect2 - 19 Standard Header File Directories
- 20 Memory Management and Type Information
- Funding Free Software
- The GNU Project and GNU/Linux
- GNU GENERAL PUBLIC LICENSE
- GNU Free Documentation License
- Contributors to GCC
- Option Index
- Concept Index
Table of Contents
- Introduction
- 1 Contributing to GCC Development
- 2 GCC and Portability
- 3 Interfacing to GCC Output
- 4 The GCC low-level runtime library
- 5 Language Front Ends in GCC
- 6 Source Tree Structure and Build System
- 6.1 Configure Terms and History
- 6.2 Top Level Source Directory
- 6.3 The gcc Subdirectory
- 6.3.1 Subdirectories of gcc
- 6.3.2 Configuration in the gcc Directory
- 6.3.3 Build System in the gcc Directory
- 6.3.4 Makefile Targets
- 6.3.5 Library Source Files and Headers under the gcc Directory
- 6.3.6 Headers Installed by GCC
- 6.3.7 Building Documentation
- 6.3.8 Anatomy of a Language Front End
- 6.3.9 Anatomy of a Target Back End
- 6.4 Testsuites
- 6.4.1 Idioms Used in Testsuite Code
- 6.4.2 Directives used within DejaGnu tests
- 6.4.3 Ada Language Testsuites
- 6.4.4 C Language Testsuites
- 6.4.5 The Java library testsuites.
- 6.4.6 Support for testing gcov
- 6.4.7 Support for testing profile-directed optimizations
- 6.4.8 Support for testing binary compatibility
- 7 Option specification files
- 8 Passes and Files of the Compiler
- 9 Trees: The intermediate representation used by the C and C++ front ends
- 10 Analysis and Optimization of GIMPLE Trees
- 11 Analysis and Representation of Loops
- 12 RTL Representation
- 12.1 RTL Object Types
- 12.2 RTL Classes and Formats
- 12.3 Access to Operands
- 12.4 Access to Special Operands
- 12.5 Flags in an RTL Expression
- 12.6 Machine Modes
- 12.7 Constant Expression Types
- 12.8 Registers and Memory
- 12.9 RTL Expressions for Arithmetic
- 12.10 Comparison Operations
- 12.11 Bit-Fields
- 12.12 Vector Operations
- 12.13 Conversions
- 12.14 Declarations
- 12.15 Side Effect Expressions
- 12.16 Embedded Side-Effects on Addresses
- 12.17 Assembler Instructions as Expressions
- 12.18 Insns
- 12.19 RTL Representation of Function-Call Insns
- 12.20 Structure Sharing Assumptions
- 12.21 Reading RTL
- 13 Control Flow Graph
- 14 Machine Descriptions
- 14.1 Overview of How the Machine Description is Used
- 14.2 Everything about Instruction Patterns
- 14.3 Example of
define_insn - 14.4 RTL Template
- 14.5 Output Templates and Operand Substitution
- 14.6 C Statements for Assembler Output
- 14.7 Predicates
- 14.8 Operand Constraints
- 14.9 Standard Pattern Names For Generation
- 14.10 When the Order of Patterns Matters
- 14.11 Interdependence of Patterns
- 14.12 Defining Jump Instruction Patterns
- 14.13 Defining Looping Instruction Patterns
- 14.14 Canonicalization of Instructions
- 14.15 Defining RTL Sequences for Code Generation
- 14.16 Defining How to Split Instructions
- 14.17 Including Patterns in Machine Descriptions.
- 14.18 Machine-Specific Peephole Optimizers
- 14.19 Instruction Attributes
- 14.19.1 Defining Attributes and their Values
- 14.19.2 Attribute Expressions
- 14.19.3 Assigning Attribute Values to Insns
- 14.19.4 Example of Attribute Specifications
- 14.19.5 Computing the Length of an Insn
- 14.19.6 Constant Attributes
- 14.19.7 Delay Slot Scheduling
- 14.19.8 Specifying processor pipeline description
- 14.20 Conditional Execution
- 14.21 Constant Definitions
- 14.22 Macros
- 15 Target Description Macros and Functions
- 15.1 The Global
targetmVariable - 15.2 Controlling the Compilation Driver, gcc
- 15.3 Run-time Target Specification
- 15.4 Defining data structures for per-function information.
- 15.5 Storage Layout
- 15.6 Layout of Source Language Data Types
- 15.7 Register Usage
- 15.8 Register Classes
- 15.9 Obsolete Macros for Defining Constraints
- 15.10 Stack Layout and Calling Conventions
- 15.10.1 Basic Stack Layout
- 15.10.2 Exception Handling Support
- 15.10.3 Specifying How Stack Checking is Done
- 15.10.4 Registers That Address the Stack Frame
- 15.10.5 Eliminating Frame Pointer and Arg Pointer
- 15.10.6 Passing Function Arguments on the Stack
- 15.10.7 Passing Arguments in Registers
- 15.10.8 How Scalar Function Values Are Returned
- 15.10.9 How Large Values Are Returned
- 15.10.10 Caller-Saves Register Allocation
- 15.10.11 Function Entry and Exit
- 15.10.12 Generating Code for Profiling
- 15.10.13 Permitting tail calls
- 15.10.14 Stack smashing protection
- 15.11 Implementing the Varargs Macros
- 15.12 Trampolines for Nested Functions
- 15.13 Implicit Calls to Library Routines
- 15.14 Addressing Modes
- 15.15 Anchored Addresses
- 15.16 Condition Code Status
- 15.17 Describing Relative Costs of Operations
- 15.18 Adjusting the Instruction Scheduler
- 15.19 Dividing the Output into Sections (Texts, Data, ...)
- 15.20 Position Independent Code
- 15.21 Defining the Output Assembler Language
- 15.21.1 The Overall Framework of an Assembler File
- 15.21.2 Output of Data
- 15.21.3 Output of Uninitialized Variables
- 15.21.4 Output and Generation of Labels
- 15.21.5 How Initialization Functions Are Handled
- 15.21.6 Macros Controlling Initialization Routines
- 15.21.7 Output of Assembler Instructions
- 15.21.8 Output of Dispatch Tables
- 15.21.9 Assembler Commands for Exception Regions
- 15.21.10 Assembler Commands for Alignment
- 15.22 Controlling Debugging Information Format
- 15.23 Cross Compilation and Floating Point
- 15.24 Mode Switching Instructions
- 15.25 Defining target-specific uses of
__attribute__ - 15.26 Defining coprocessor specifics for MIPS targets.
- 15.27 Parameters for Precompiled Header Validity Checking
- 15.28 C++ ABI parameters
- 15.29 Miscellaneous Parameters
- 15.1 The Global
- 16 Host Configuration
- 17 Makefile Fragments
- 18
collect2 - 19 Standard Header File Directories
- 20 Memory Management and Type Information
- Funding Free Software
- The GNU Project and GNU/Linux
- GNU GENERAL PUBLIC LICENSE
- GNU Free Documentation License
- Contributors to GCC
- Option Index
- Concept Index
Next: Contributing, Up: (DIR)
Introduction
This manual documents the internals of the GNU compilers, including how to port them to new targets and some information about how to write front ends for new languages. It corresponds to GCC version 4.2.1. The use of the GNU compilers is documented in a separate manual. See Introduction.
This manual is mainly a reference manual rather than a tutorial. It discusses how to contribute to GCC (see Contributing), the characteristics of the machines supported by GCC as hosts and targets (see Portability), how GCC relates to the ABIs on such systems (see Interface), and the characteristics of the languages for which GCC front ends are written (see Languages). It then describes the GCC source tree structure and build system, some of the interfaces to GCC front ends, and how support for a target system is implemented in GCC.
Additional tutorial information is linked to from http://gcc.gnu.org/readings.html.