The Pocket Handbook of Image Processing Algorithms in C (1993) [pdf]

Re:The Pocket Handbook of Image Processing Algorithms in C (... by wtracy on Sunday June 01, 2014 @03:13AM (#7828420)

Do note that modern compilers can detect when the return value of the ++ operator is unused, and skip the extra steps when unneeded. (I've verified the resulting assembler myself from GCC 3.X.) That said, I still use the prefix notation because I can't come up with a good reason not to.

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Re:The Pocket Handbook of Image Processing Algorithms in C (... by NAFV_P on Sunday June 01, 2014 @03:21AM (#7828443)

> Do note that modern compilers can detect when the return value of the ++ operator is unused, and skip the extra steps when unneeded.

Is there an equivalent instruction in assembly for postfix increment/decrement?

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Re:The Pocket Handbook of Image Processing Algorithms in C (... by wtracy on Sunday June 01, 2014 @03:53AM (#7828490)

Neither one really has a direct "equivalent" in assembly.

Prefix is going to look something like:

  inc eax # increment the value
  mov eax,ecx # copy the return value to its destination

Postfix is going to look something like:

  mov eax,ebx # copy original value
  inc eax # increment value
  mov ebx,ecx # copy original value to final destination

The actual code you'd get would vary a lot between compilers, architectures, and even just different contexts within the same compiler-architecture combination.

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Re:The Pocket Handbook of Image Processing Algorithms in C (... by NAFV_P on Sunday June 01, 2014 @05:19AM (#7828624)

Thank you, dammit I really should learn assembly.

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