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Unformatted text preview: tended integer extended Source Location ÅÑ Ö ÅÑ Ö Å Ñ½¼ Ö ÅÑ Ö %st( ) 179 Figure 3.30: Floating-Point Load Instructions. All convert the operand to extended-precision format and push it onto the register stack. by introducing variants of the arithmetic instructions that leave their second operand on the stack, and that can use an arbitrary stack value as their second operand. In addition, it provides an instruction that can swap the top stack element with any other element. Although these extensions can be used to generate more efﬁcient code, the simple and elegant algorithm for translating arithmetic expressions into stack code is lost. 3.14.4 Floating-Point Data Movement and Conversion Operations
Floating-point registers are referenced with the notation %st( ), where denotes the position relative to the top of the stack. The value can range between 0 and 7. Register %st(0) is the top stack element, %st(1) is the second element, and so on. The top stack element can also be referenced as %st. When...
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