Expressions
3-24
3.9
Expressions
An expression is a constant, a symbol, or a series of constants and symbols
separated by arithmetic operators. The range of valid expression values is
–32 768 to 32 767. Three main factors influence the order of expression evalu-
ation:
Parentheses
Expressions that are enclosed in parentheses are
always evaluated first.
8 / (4 / 2) = 4, but 8 / 4 / 2 = 1
You
cannot substitute braces ( { } ) or brackets ( [ ] )
for parentheses.
Precedence groups
The ’C54x assembler uses the same order of pre-
cedence as the C language does as summarized
in Table 3–1. This differs from the order of prece-
dence of other TMS320 assemblers. When paren-
theses do not determine the order of expression
evaluation, the highest precedence operation is
evaluated first.
8 + 4 / 2 = 10 (4 / 2 is evaluated first)
Left-to-right evaluation When parentheses and precedence groups do not
determine the order of expression evaluation, the
expressions are evaluated as happens in the C
language.
8 / 4*2 = 4 , but 8 / (4*2) = 1
Summary of Contents for TMS320C54x
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