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Update documentation slightly; remove weird special-casing of -O2 and -O3

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H. Peter Anvin 2003-08-29 19:25:46 +00:00
parent 16b929515e
commit 9173ab9961
2 changed files with 8 additions and 9 deletions
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16
doc/nasmdoc.src
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@ -739,9 +739,8 @@ The syntax is:
\b \c{-On} multi-pass optimization, minimize branch offsets; also will
minimize signed immediate bytes, overriding size specification
unless the \c{strict} keyword has been used (see \k{strict}).
If 2 <= n <= 3, then there are 5 * n passes, otherwise there
are n passes.
The number specifies the maximum number of passes. The more
passes, the better the code, but the slower is the assembly.
Note that this is a capital O, and is different from a small o, which
is used to specify the output format. See \k{opt-o}.
@ -1646,7 +1645,7 @@ forcing byte size in the effective address by coding \c{[byte
ebx+offset]}.
Note that use of the \c{-On} switch (with n>=2) makes some of the above
no longer true. (see \k{opt-On})
no longer true (see \k{opt-On}).
\H{locallab} \i{Local Labels}
@ -6112,14 +6111,15 @@ that isn't listed here.
\S{inefficient} NASM Generates \i{Inefficient Code}
I get a lot of `bug' reports about NASM generating inefficient, or
We sometimes get `bug' reports about NASM generating inefficient, or
even `wrong', code on instructions such as \c{ADD ESP,8}. This is a
deliberate design feature, connected to predictability of output:
NASM, on seeing \c{ADD ESP,8}, will generate the form of the
instruction which leaves room for a 32-bit offset. You need to code
\I\c{BYTE}\c{ADD ESP,BYTE 8} if you want the space-efficient
form of the instruction. This isn't a bug: at worst it's a
misfeature, and that's a matter of opinion only. See \k{opt-On}.
\I\c{BYTE}\c{ADD ESP,BYTE 8} if you want the space-efficient form of
the instruction. This isn't a bug, it's user error: if you prefer to
have NASM produce the more efficient code automatically enable
optimization with the \c{-On} option (see \k{opt-On}).
\S{jmprange} My Jumps are Out of Range\I{out of range, jumps}

1
nasm.c
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@ -403,7 +403,6 @@ static int process_arg (char *p, char *q)
while(isdigit(*++param)) ;
if (opt<=0) optimizing = -1; /* 0.98 behaviour */
else if (opt==1) optimizing = 0; /* Two passes, 0.98.09 behavior */
else if (opt<=3) optimizing = opt*5; /* Multiple passes */
else optimizing = opt; /* Multiple passes */
} else {
if (*param == 'v' || *param == '+') {