• SL <SL_member pathlink.com> Feb 26 2004
• SL <SL_member pathlink.com> Feb 26 2004
• SL <SL_member pathlink.com> Feb 26 2004
• "Walter" <walter digitalmars.com> Feb 26 2004

First, this isn't an urgent problem which I need help with IMMEDIATELY. I've
already worked around it, so suggestions on how to work around it would be
pointless, but I'm thinking it might be a bug in DMC, so I'm posting about it.
Or I might be using the wrong compiler-options, so I'm including my compile-line
and .def file in this post.

I'm wondering why DMC is complaining about this bit of asm:

DMC said:
                fmul st(0), st(0)
                                ^
 noctis-0.cpp(2923) : Error: Illegal type/size of operands for the fmul
instruction


(That's exact line is used in two places, DMC complained about both)

It also complains about fmulp st(1), st(0) - I had thought it just didn't like
multiplying st(0) times st(0), so did fld st(0) followed by fmulp st(1), st(0),
and it complains. However, it doesn't complain about 'fmulp' with no args -
which according to Intel's IA-32 Instruction Set Reference manual, is just a
short way to write fmulp st(1), st(0):

From said manual:
Opcode    Instruction         Description
-----------------------------------------
D8 C8+i   FMUL ST(0), ST(i)   Multiply ST(0) by ST(i) and store result in ST(0)
DC C8+i   FMUL ST(i), ST(0)   Multiply ST(i) by ST(0) and store result in ST(0)
DE C8+i   FMULP ST(i), ST(0)  Multiply ST(i) by ST(0), store result in ST(i),
and pop the register stack
DE C9     FMULP               Multiply ST(i) by ST(0), store result in ST(i),
and pop the register stack

P.S. Compile lines:
dmc.exe noctis.cpp noctis-0.cpp noctis-1.cpp noctis.def -oNoctis_D -mld -gp -s
-Ju -L/co/ma -g -cpp | more
dmc.exe noctis.cpp noctis-0.cpp noctis-1.cpp noctis.def -oNoctis -gp -s -Ju -mld
-cpp | more

Def file:
EXETYPE DOS
REALMODE


(For anyone curious, Noctis is a free game, the source is posted on the site for
it, but it was made with BC 3.1, a really old DOS compiler. I'm fiddling to see
if I can get it compiling with DM.)

-SL

I wish we could edit what we posted. Guess I should re-read my message(s) BEFORE
posting them here. :P

Corrections:

(That's exact line is used in two places, DMC complained about both)


both)

DE C9     FMULP               Multiply ST(i) by ST(0), store result in ST(i),
and pop the register stack



The rest is correct.

-SL

Huh. I attempted to post corrections once already, but the post seems to have
vanished into the clear blue sky.

Let's try again...

(That's exact line is used in two places, DMC complained about both)



DE C9     FMULP               Multiply ST(i) by ST(0), store result in ST(i),



The rest looks correct.

-SL

    FMUL st, st(0)

should work.

"SL" <SL_member pathlink.com> wrote in message
news:c1kvdv$a3p$1 digitaldaemon.com...
 First, this isn't an urgent problem which I need help with IMMEDIATELY.


 already worked around it, so suggestions on how to work around it would be
 pointless, but I'm thinking it might be a bug in DMC, so I'm posting about


 Or I might be using the wrong compiler-options, so I'm including my


 and .def file in this post.

 I'm wondering why DMC is complaining about this bit of asm:

 DMC said:
                fmul st(0), st(0)
                                ^
 noctis-0.cpp(2923) : Error: Illegal type/size of operands for the fmul




 (That's exact line is used in two places, DMC complained about both)

 It also complains about fmulp st(1), st(0) - I had thought it just didn't


 multiplying st(0) times st(0), so did fld st(0) followed by fmulp st(1),


 and it complains. However, it doesn't complain about 'fmulp' with no


 which according to Intel's IA-32 Instruction Set Reference manual, is just


 short way to write fmulp st(1), st(0):

 From said manual:
 Opcode    Instruction         Description
 -----------------------------------------
 D8 C8+i   FMUL ST(0), ST(i)   Multiply ST(0) by ST(i) and store result in


 DC C8+i   FMUL ST(i), ST(0)   Multiply ST(i) by ST(0) and store result in


 DE C8+i   FMULP ST(i), ST(0)  Multiply ST(i) by ST(0), store result in


 and pop the register stack
 DE C9     FMULP               Multiply ST(i) by ST(0), store result in


 and pop the register stack

 P.S. Compile lines:
 dmc.exe noctis.cpp noctis-0.cpp noctis-1.cpp


 -Ju -L/co/ma -g -cpp | more
 dmc.exe noctis.cpp noctis-0.cpp noctis-1.cpp


 -cpp | more

 Def file:
 EXETYPE DOS
 REALMODE


 (For anyone curious, Noctis is a free game, the source is posted on the


 it, but it was made with BC 3.1, a really old DOS compiler. I'm fiddling


 if I can get it compiling with DM.)

 -SL