gcc: Using Assembly Language with C

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1 6.45 How to Use Inline Assembly Language in C Code
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1 The 'asm' keyword allows you to embed assembler instructions within C
1 code.  GCC provides two forms of inline 'asm' statements.  A "basic
1 'asm'" statement is one with no operands (⇒Basic Asm), while an
1 "extended 'asm'" statement (⇒Extended Asm) includes one or more
1 operands.  The extended form is preferred for mixing C and assembly
1 language within a function, but to include assembly language at top
1 level you must use basic 'asm'.
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1  You can also use the 'asm' keyword to override the assembler name for a
1 C symbol, or to place a C variable in a specific register.
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Menu

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· Basic Asm          Inline assembler without operands.
· Extended Asm       Inline assembler with operands.
· Constraints        Constraints for 'asm' operands
· Asm Labels         Specifying the assembler name to use for a C symbol.
· Explicit Register Variables  Defining variables residing in specified
1                        registers.
· Size of an asm     How GCC calculates the size of an 'asm' block.
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