Commit Graph

3 Commits

Author SHA1 Message Date
H. Peter Anvin
d235408c65 preproc: standard macros now C-safe, %aliases off, fix %? recursion
Enough users expect the namespace starting with underscore to be safe
for symbols. Change our private namespace from __foo__ to
__?foo?__. Use %defalias to provide backwards compatiblity (by using
%defalias instead of %define, we handle the case properly where the
user changes the value.)

Add a preprocessor directive:

%aliases off

... to disable all smacro aliases and thereby making the namespace
clean.

Finally, fix infinite recursion when seeing %? or %?? due to
paste_tokens(). If we don't paste anything, the expansion is done.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2019-08-27 16:42:41 -07:00
H. Peter Anvin
aa958b1ab6 ifunc.mac: the ilog2 warning may want to be both ceil and floor
There is no reason why the warning-generating ilog2 has to be only the
floor variant.  However, I am pretty sure we can simply implement the
ilog2cw() as a macro only; we can always fix that if that turns out to
be incorrect.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2016-05-24 23:03:17 -07:00
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