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GNU inline assembly

The gnu compile is instucted to insert inline assembly code with the asm or __asm__ keyword.
The general form of asm() is: 
asm (
  "assembler code" :
   outputs         :
   inputs          :
   clobbers
);
The compiler does not parse the passed assembler instructions.

Outputs and inputs

The outputs and the inputs is a list of comma separated operands.

Operands

An operand is described by an operand-constraint string followed by a C expression in parentheses.
Output operands are indicated by an = sign. Of course, these must be lvalues.

Operand constraint strings

Index