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nosplit: Generate index-only EA only when a multiplier is used.

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[nosplit eax] has been encoded as [eax*1+0] since 0.98.34.
But this seems like unexpected behavior.
So only when a register is multiplied, that will be treated
as an index. ([nosplit eax*1] -> [eax*1+0])
Document is updated accordingly.

Signed-off-by: Jin Kyu Song <jin.kyu.song@intel.com>
This commit is contained in:
Jin Kyu Song 2013-12-18 22:01:14 -08:00
parent b0c729baeb
commit 26ddad67ca
2 changed files with 5 additions and 3 deletions
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5
assemble.c
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@ -2635,9 +2635,10 @@ static enum ea_type process_ea(operand *input, ea *output, int bits,
bt = it, bx = ix, s--;
}
if (it == -1 && (bt & 7) != REG_NUM_ESP &&
(eaflags & EAF_TIMESTWO)) {
(eaflags & EAF_TIMESTWO) &&
(hb == b && ht == EAH_NOTBASE)) {
/*
* convert [NOSPLIT EAX]
* convert [NOSPLIT EAX*1]
* to sib format with 0x0 displacement - [EAX*1+0].
*/
it = bt, ix = bx, bt = -1, bx = 0, s = 1;

3
doc/nasmdoc.src
View File

@ -1459,7 +1459,8 @@ that allows the offset field to be absent and space to be saved; in
fact, it will also split \c{[eax*2+offset]} into
\c{[eax+eax+offset]}. You can combat this behaviour by the use of
the \c{NOSPLIT} keyword: \c{[nosplit eax*2]} will force
\c{[eax*2+0]} to be generated literally.
\c{[eax*2+0]} to be generated literally. \c{[nosplit eax*1]} also has the
same effect. In another way, a split EA form \c{[0, eax*2]} can be used, too.
However, \c{NOSPLIT} in \c{[nosplit eax+eax]} will be ignored because user's
intention here is considered as \c{[eax+eax]}.