(→Postfix Code) |
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Line 3: | Line 3: | ||
Consider the following C function: | Consider the following C function: | ||
− | <c> | + | <source lang="c"> |
int *click(int *x, int dim) { | int *click(int *x, int dim) { | ||
int *res, i; | int *res, i; | ||
Line 10: | Line 10: | ||
return res; | return res; | ||
} | } | ||
− | </ | + | </source> |
== Postfix Code == | == Postfix Code == | ||
Line 16: | Line 16: | ||
The Postfix code for the above function is as follows: | The Postfix code for the above function is as follows: | ||
{{CollapsedCode|Postfix code| | {{CollapsedCode|Postfix code| | ||
− | <asm> | + | <source lang="asm"> |
TEXT | TEXT | ||
ALIGN | ALIGN | ||
Line 121: | Line 121: | ||
LEAVE | LEAVE | ||
RET | RET | ||
− | </ | + | </source> |
}} | }} | ||
Consider the following C function:
int *click(int *x, int dim) {
int *res, i;
for (i = dim-2, res = x+dim-1; i >= 0; i--)
if (x[i] > *res) res = &x[i];
return res;
}
The Postfix code for the above function is as follows:
Postfix code |
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TEXT
ALIGN
GLOBL click, FUNC
LABEL click
ENTER 8 ;-- x@+8 dim@+12 res@-4 i@-8
;; for init
;; i = dim-2
LOCAL 12
LDINT
INT 2
SUB
DUP32
LOCAL -8
STINT
TRASH 4
;; res = x + dim - 1
LOCAL 8
LDINT
LOCAL 12
LDINT
INT 4
MUL
ADD
INT 1
INT 4
MUL
SUB
DUP32
LOCAL -4
STINT
TRASH 4
;; for test
ALIGN
LABEL for
LOCAL -8
LDINT
INT 0
GE
JZ forend
;; for block
;; if test
LOCAL 8
LDINT ; x
LOCAL -8
LDINT; i
INT 4
MUL
ADD ; x+i
LDINT ; x[i] = *(x+i)
LOCAL -4
LDINT ; res
LDINT ; *res
GT
JZ ifend
;; if block
LOCAL 8
LDINT ; x
LOCAL -8
LDINT ; i
INT 4
MUL
ADD ; x+i = &x[i]
DUP32
LOCAL -4
STINT ; res = &x[i]
TRASH 4
ALIGN
LABEL ifend
;; for increment
ALIGN
LABEL forincr
LOCAL -8
LDINT ; i
DUP32
INT 1
SUB
LOCAL -8
STINT
TRASH 4
;; for jump to cycle
JMP for
ALIGN
LABEL forend
;; return
LOCAL -4
LDINT ; res
STFVAL32
LEAVE
RET
|
To compile the Postfix code directly, pf2asm can be used: