mshiels@tmsoft.uucp (Michael A. Shiels) (06/13/90)
One of my co workers was trying to start using Microsoft C 6.0 but found out
that it's just like Microsfot C 5.1. You have to disable most of the
optimizations so it will generate correct code. Here's his very simple sample
code which doesn't have anything to do with loops but is broken when you specify
loop optimizations.
/**************************************************************************/
/* cl -c -Gs -Zl -FPc -Oswrl -Awfl -W4 -Fa c6badeg.c */
/* */
/* NOTE: THIS WORKS IF THE '-O...l' IS NOT INCLUDED! */
/* I PERSONALLY DON'T KNOW WHAT LOOP OPTIMIZATION HAS TO DO WITH */
/* THIS CODE. */
/* '-Oswer' DOESN'T WORK EITHER!! */
/**************************************************************************/
struct graphd {
double mins[2];
double maxs[2];
};
extern struct graphd *CurrentGraph;
void check_range(
double *val,
int range)
{
if (*val > CurrentGraph->maxs[range])
CurrentGraph->maxs[range] = *val;
if (*val < CurrentGraph->mins[range])
CurrentGraph->mins[range] = *val;
}
/**************************************************************************/
/*
; Static Name Aliases
;
TITLE c6badeg.c
.8087
C6BADEG_TEXT SEGMENT WORD PUBLIC 'CODE'
C6BADEG_TEXT ENDS
_DATA SEGMENT WORD PUBLIC 'DATA'
_DATA ENDS
CONST SEGMENT WORD PUBLIC 'CONST'
CONST ENDS
_BSS SEGMENT WORD PUBLIC 'BSS'
_BSS ENDS
DGROUP GROUP CONST, _BSS, _DATA
ASSUME DS: DGROUP
ASSUME SS: NOTHING
EXTRN __aFeldd:FAR
EXTRN __aFfcompp:FAR
EXTRN _CurrentGraph:DWORD
EXTRN __fltused:NEAR
C6BADEG_TEXT SEGMENT
ASSUME CS: C6BADEG_TEXT
; Line 1
; Line 14
C6BADEG_TEXT ENDS
CONST SEGMENT
$T20001 DW SEG _CurrentGraph
CONST ENDS
C6BADEG_TEXT SEGMENT
ASSUME CS: C6BADEG_TEXT
PUBLIC _check_range
_check_range PROC FAR
push bp
mov bp,sp
push di
push si
; val = 6
; range = 10
; Line 15
les bx,DWORD PTR [bp+6] ;val
call FAR PTR __aFeldd
mov es,WORD PTR $T20001
les bx,DWORD PTR es:_CurrentGraph
add bx,16
mov cl,3
mov si,WORD PTR [bp+10] ;range
shl si,cl
lea bx,WORD PTR [bx][si]
call FAR PTR __aFeldd
call FAR PTR __aFfcompp
jae $I106
; Line 16
mov cl,3
mov bx,WORD PTR [bp+10] ;range
shl bx,cl
mov es,WORD PTR $T20001
les si,DWORD PTR es:_CurrentGraph
mov ax,WORD PTR [bp+6] ;val
mov dx,WORD PTR [bp+8]
push ds
lea di,WORD PTR [bx+16][si]
mov si,ax
mov ds,dx
ASSUME DS: NOTHING
movsw
movsw
movsw
movsw
pop ds
ASSUME DS: DGROUP
; Line 17
$I106:
les bx,DWORD PTR [bp+6] ;val
call FAR PTR __aFeldd
mov es,WORD PTR $T20001
les bx,DWORD PTR es:_CurrentGraph
mov cl,3
mov si,WORD PTR [bp+10] ;range
shl si,cl
lea bx,WORD PTR [bx][si]
call FAR PTR __aFeldd
call FAR PTR __aFfcompp
jbe $EX105
; Line 18
mov es,WORD PTR $T20001
les bx,DWORD PTR es:_CurrentGraph
mov si,WORD PTR [bp+6] ;val
mov dx,WORD PTR [bp+8]
push ds
lea di,WORD PTR [bx][si]
mov ds,dx
ASSUME DS: NOTHING
movsw
movsw
movsw
movsw
pop ds
ASSUME DS: DGROUP
; Line 19
$EX105:
pop si
pop di
mov sp,bp
pop bp
ret
_check_range ENDP
C6BADEG_TEXT ENDS
END
*/