From: THIERRY DOT T DOT I DOT IMMORDINO AT TSI DOT thomson DOT fr
Date: 06 Mar 1998 17:55:05 -0100
Delivery-Date: 06 Mar 1998 18:21:42 +0000
Message-Type: Multiple Part
Original-Encoded-Information-Types: IA5-Text
Message-ID: <0002420A.MAI*/G=THIERRY/I=TI/S=IMMORDINO/O=TSI/PRMD=THOMSON/ADMD=ATLAS/C=FR@MHS>
Importance: normal
Subject: Multitask and FPU emulator
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To: djgpp AT delorie DOT com
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Content-Identifier: CSI NC V3.0
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Hi,

I try to implement multitask kernel on a i386ex target, and I have some 
problems with the FPU emulator.

Can anyone translate that kind of message from the emulator :

80387 Exception: stack underflow!
  SW: 0x11c1  top=2 cc=0001    CW: 0x037e
st(4) + .904e 04a0 0000 0000 e+3     Valid
st(5) + .904e 04a0 0000 0000 e+3     Valid


The execution seems to crash near the address $16A2 :

#39:     for (d = 0.; d < 10.; d++) {
00001696 fldz
#40:       f += (float)sin (0.7);
00001698 push    0x3fe66666
0000169d push    0x66666666
000016a2 fstpt   [ebp-100]
000016a5 fstpt   [ebp-112]
000016a8 call    _sin
000016ad fstp    [ebp-88]
000016b0 fld     [ebp-88]
000016b3 fldt    [ebp-112]
000016b6 faddp   st(1),st
#41:       sprintf (str, "%f %f", d, f);
000016b8 fld     st(0)
...


Merci

Thierry