dmul

dmul

Forms
dmul = 107 (0x6b)

Stack
..., value1.word1, value1.word2, value2.word1, value2.word2 ..., result.word1, result.word2

Description
Both value1 and value2 must be of type double. The values are popped from the operand stack. The double result is value1 * value2. The result is pushed onto the operand stack.

The result of a dmul instruction is governed by the rules of IEEE arithmetic:

• If either value is NaN, the result is NaN.
• If neither value is NaN, the sign of the result is positive if both values have the same sign, and negative if the values have different signs.
• Multiplication of an infinity by a zero results in NaN.
• Multiplication of an infinity by a finite value results in a signed infinity, with the sign-producing rule just given.
• In the remaining cases, where neither an infinity nor NaN is involved, the product is computed and rounded to the nearest representable value using IEEE 754 round-to-nearest mode. If the magnitude is too large to represent as a double, we say the operation overflows; the result is then an infinity of appropriate sign. If the magnitude is too small to represent as a double, we say the operation underflows; the result is then a zero of appropriate sign.

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Java Virtual Machine Specification (HTML generated by dkramer on February 25, 1997)
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