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There is disagreement within many languages as to what constitutes idiomatic usage of exceptions. For example, Joshua Bloch states that Java's exceptions should only be used for exceptional situations, [2] but Kiniry observes that Java's built-in FileNotFoundException is not at all an exceptional event. [3]
Some architectures may be configured to automatically generate an exception on an operation resulting in overflow. An example, suppose we add 127 and 127 using 8-bit registers. 127+127 is 254, but using 8-bit arithmetic the result would be 1111 1110 binary, which is the two's complement encoding of −2, a negative number. A negative sum of ...
The register width of a processor determines the range of values that can be represented in its registers. Though the vast majority of computers can perform multiple-precision arithmetic on operands in memory, allowing numbers to be arbitrarily long and overflow to be avoided, the register width limits the sizes of numbers that can be operated on (e.g., added or subtracted) using a single ...
The first hardware exception handling was found in the UNIVAC I from 1951. Arithmetic overflow executed two instructions at address 0 which could transfer control or fix up the result. [16] Software exception handling developed in the 1960s and 1970s. Exception handling was subsequently widely adopted by many programming languages from the ...
For example in Java, such operations throw instances of java.lang.ArithmeticException. [25] In C , they lead to undefined behavior , but if annex F is supported, the operation yields an "invalid" floating-point exception (as required by the IEEE standard) and an unspecified value.
Most assembly languages will have a macro instruction or an interrupt address available for the particular system to intercept events such as illegal op codes, program check, data errors, overflow, divide by zero, and other such.
Variable-length arithmetic operations are considerably slower than fixed-length format floating-point instructions. When high performance is not a requirement, but high precision is, variable length arithmetic can prove useful, though the actual accuracy of the result may not be known.
Off-by-one errors are common in using the C library because it is not consistent with respect to whether one needs to subtract 1 byte – functions like fgets() and strncpy will never write past the length given them (fgets() subtracts 1 itself, and only retrieves (length − 1) bytes), whereas others, like strncat will write past the length given them.