Aliasing Assumptions - Intel i960 User Manual

Caveats
This chapter provides useful programming tips on:
•

Aliasing assumptions

•
Alignment assumptions
•
Volatile object
•
Known problems
•
C version incompatibilities
•
Troubleshooting
Aliasing Assumptions
Some compiler optimizations (for example,
information as the basis for several assumptions. These assumptions
exclude some pairs of memory references as possible alias candidates.
If your program violates these assumptions, the compiler may generate
code that does not function as you intended.
Here are the rules the compiler uses:
character
ordinal
real
fshadow-mem
(i.e., ,
char unsigned char
lvalues can access all objects, regardless of type.
(e.g., , ,
int short long
access only ordinal objects of the same size
(regardless of sign) or character objects.
(e.g., , ,
float double long double
access only real objects of the same size, or
character objects.
) use type
, )
signed char
, ) lvalues can
enum
) lvalues can
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