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Unformatted text preview: he required source values, execute the assembly instructions, and make use of the computed results. It will also have information it requires about register usage so that important program values are not overwritten by the assembly code instructions. 190 CHAPTER 3. MACHINE-LEVEL REPRESENTATION OF C PROGRAMS The general syntax of an extended assembly sequence is as follows: asm( code-string : output-list : input-list : overwrite-list ); where the square brackets denote optional arguments. The declaration contains a string describing the assembly code sequence, followed by optional lists of outputs (i.e., results generated by the assembly code), inputs (i.e., source values for the assembly code), and registers that are overwritten by the assembly code. These lists are separated by the colon (‘:’) character. As the square brackets show, we only include lists up to the last nonempty list. The syntax for the code string is reminiscent of that for the format string in a printf statement. It consists of a sequence of assembly code instructions separated by the semicolon (‘;’)...
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- Spring '10
- The American