nasm/macros/ifunc.mac
H. Peter Anvin 290b4cb3a4 eval: add general support for "integer functions" and add ilog2*()
Add general support in the function parser for "integer functions"
(actually implemented as special unary operators, then wrapped in
macros) and implement a family of integer logarithms.  The only
difference is the behavior on a non-power-of-two argument:

	ilog2[e]	-- throw an error
	ilog2w		-- throw a warning
	ilog2f		-- round down to power of 2
	ilog2c		-- round up to power of 2

This is useful for back-converting from masks to bit values.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2012-05-31 10:25:37 -07:00

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;; --------------------------------------------------------------------------
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;; Copyright 2012 The NASM Authors - All Rights Reserved
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;; ifunc.mac
;;
;; Integer function utility macros
;;
USE: ifunc
%idefine ilog2(x) (__ilog2e__(x))
%idefine ilog2e(x) (__ilog2e__(x))
%idefine ilog2w(x) (__ilog2w__(x))
%idefine ilog2f(x) (__ilog2f__(x))
%idefine ilog2c(x) (__ilog2c__(x))