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Unformatted text preview: mputations combine to make the machine code lengthy and obscure. It is remarkable that the modern processors manufactured by Intel and its competitors can achieve respectable performance on numeric programs given the form in which they are encoded. 3.15 *Embedding Assembly Code in C Programs
In the early days of computing, most programs were written in assembly code. Even large-scale operating systems were written without the help of high-level languages. This becomes unmanageable for programs of signiﬁcant complexity. Since assembly code does not provide any form of type checking, it is very easy 3.15. *EMBEDDING ASSEMBLY CODE IN C PROGRAMS 187 to make basic mistakes, such as using a pointer as an integer rather than dereferencing the pointer. Even wors, writing in assembly code locks the entire program into a particular class of machine. Rewriting an assembly language program to run on a different machine can be as difﬁcult as writing the entire program from scratch.
Aside: Writing large programs in assembly code. Frederick Brooks, Jr., a pioneer in...
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- Spring '10
- The American