How to compile with Bruce's C Compiler to get asm file that runs on 8086 processors

Question

I have this small c code

    int main (){
    int in  [50];
    int res [50];

    int avg=0;
    int i=0;
    int j=0;

    for(i=0;i<50;i++){
      in[i]=i*5+28%25;
    }

    for(i=0;i<50;i++){
        avg=0;
        for(j=i-4;j<=i+5;j++){
            if((j>=0)&&(j<50)){
                avg=avg+in[j];
            }
            avg=avg/10;
            res[i]=avg;
        }
    }
    return 0;
}

which is a simple moving average function

I want to get the assembly code that corresponds to this code, however, I want the x86 ISA assembly code that can run on processor 8086

after looking I ran this commands

bcc -ansi -c -o foo.o foo.c
as86 foo.asm -o foo.o

this ended up with error

as: error opening input file

how can I compile my file to get the assembly code?

Well, since you told it to produce an object file named foo.o, I'm not sure why you think an assembly file is available. Read the manual page for your compiler and look for "Assembly output." — David Hoelzer, Nov 07 '17 at 22:10
@bruceg : that is for GCC, this is for BCC (Bruce's C Compiler) — Michael Petch, Nov 07 '17 at 22:14
I have removed the _BCC_ tag you keep putting back. It was removed because that tag is for `blind carbon copy` not Bruce's C compiler. You can click on the tag to get a description of it. — Michael Petch, Nov 07 '17 at 22:19

score 4 · Accepted Answer · answered Nov 07 '17 at 23:12

Try bcc -S to get assembly. For example, if you type bcc -ansi -S foo.c you get foo.s with the following content (debug comments removed for brevitiy):

export  _main
_main:
push    bp
mov bp,sp
push    di
push    si
add sp,#-$CA
xor ax,ax
mov -$CE[bp],ax
dec sp
dec sp
xor ax,ax
mov -$D0[bp],ax
dec sp
dec sp
xor ax,ax
mov -$D2[bp],ax
xor ax,ax
mov -$D0[bp],ax
jmp .3
.4:
mov ax,-$D0[bp]
mov dx,ax
shl ax,*1
shl ax,*1
add ax,dx
add ax,*3
push    ax
mov ax,-$D0[bp]
shl ax,*1
mov bx,bp
add bx,ax
mov ax,-$D4[bp]
mov -$68[bx],ax
inc sp
inc sp
.2:
mov ax,-$D0[bp]
inc ax
mov -$D0[bp],ax
.3:
mov ax,-$D0[bp]
cmp ax,*$32
jl  .4
.5:
.1:
xor ax,ax
mov -$D0[bp],ax
jmp .8
.9:
xor ax,ax
mov -$CE[bp],ax
mov ax,-$D0[bp]
add ax,*-4
mov -$D2[bp],ax
jmp .C
.D:
mov ax,-$D2[bp]
test    ax,ax
jl      .E
.10:
mov ax,-$D2[bp]
cmp ax,*$32
jge     .E
.F:
mov ax,-$D2[bp]
shl ax,*1
mov bx,bp
add bx,ax
mov ax,-$CE[bp]
add ax,-$68[bx]
mov -$CE[bp],ax
.E:
mov ax,-$CE[bp]
mov bx,*$A
cwd
idiv    bx
mov -$CE[bp],ax
mov ax,-$D0[bp]
shl ax,*1
mov bx,bp
add bx,ax
mov ax,-$CE[bp]
mov -$CC[bx],ax
.B:
mov ax,-$D2[bp]
inc ax
mov -$D2[bp],ax
.C:
mov ax,-$D0[bp]
add ax,*5
cmp ax,-$D2[bp]
jge .D
.11:
.A:
.7:
mov ax,-$D0[bp]
inc ax
mov -$D0[bp],ax
.8:
mov ax,-$D0[bp]
cmp ax,*$32
blt     .9
.12:
.6:
xor ax,ax
lea sp,-4[bp]
pop si
pop di
pop bp
ret
.data
.bss

@AmrAyman Pass `-O` to the compiler. Read the man page of `bcc` for more details. — fuz, Nov 09 '17 at 20:39

How to compile with Bruce's C Compiler to get asm file that runs on 8086 processors

1 Answers1