Code Generation/Exercise 11: Difference between revisions
From Wiki**3
< Code Generation
| Line 31: | Line 31: | ||
RODATA | RODATA | ||
ALIGN | ALIGN | ||
LABEL limit | LABEL limit ; not really this name | ||
CONST 1024 | CONST 1024 | ||
; done - go back to code segment | ; done - go back to code segment | ||
| Line 43: | Line 43: | ||
; for-loop test | ; for-loop test | ||
LABEL fortest | |||
LOCAL -4 | LOCAL -4 | ||
LOAD ; i | LOAD ; i | ||
| Line 54: | Line 55: | ||
; BEGIN assignment to v[i] | ; BEGIN assignment to v[i] | ||
; compute and promote 3*i | ; compute and promote 3*i | ||
INT 3 | INT 3 | ||
LOCAL -4 ; &i | LOCAL -4 ; &i | ||
| Line 63: | Line 64: | ||
I2D | I2D | ||
DDUP ; | DDUP ; implement assignment value | ||
; compute &v[i] == v+i*sizeof(double) | ; compute &v[i] == v+i*sizeof(double) | ||
| Line 76: | Line 77: | ||
DSTORE ; do assignment of double value | DSTORE ; do assignment of double value | ||
TRASH 8 ; discard assignment | TRASH 8 ; discard value of assignment | ||
; END assignment to v[i] | ; END assignment to v[i] | ||
| Line 102: | Line 103: | ||
INT 0 | INT 0 | ||
GT | GT | ||
; jump to if end | |||
JZ ifend | |||
; BEGIN if block | ; BEGIN if block | ||
| Line 111: | Line 115: | ||
I2D | I2D | ||
DDUP ; | DDUP ; implement assignment value | ||
; compute &v[i] == v+i*sizeof(double) | ; compute &v[i] == v+i*sizeof(double) | ||
| Line 122: | Line 126: | ||
ADD ; &v[i] | ADD ; &v[i] | ||
DSTORE ; do assignment of double value | DSTORE ; do assignment of double value | ||
TRASH 8 ; discard assignment | TRASH 8 ; discard value of assignment | ||
; END if block | ; END if block | ||
LABEL ifend | |||
; FOR increment | |||
LABEL forincr | |||
; increment expression | |||
LOCAL -4 ; &i | |||
LOAD ; i | |||
DUP | |||
INT 1 | |||
ADD | |||
LOCAL -4 ; &i | |||
STORE | |||
TRASH 4 | |||
; END for-loop body | ; END for-loop body | ||
JMP fortest | |||
LABEL forend | |||
; return *v | ; return *v | ||
LOCAL +8 ; &v | LOCAL +8 ; &v | ||
LOAD ; v | LOAD ; v | ||
DLOAD ; *v | |||
DPOP | |||
LEAVE | LEAVE | ||
RET | RET | ||
Revision as of 10:58, 17 May 2017
Problema
Considere o seguinte código C++ (assuma que ponteiros e int ocupam 32 bits e que double ocupa 64 bits).
<cpp> double *forall(double *v) {
const static int limit = 1024;
for (int i = 0; i < limit; i++) {
v[i] = 3 * i – sizeof(double);
if (v[i] > 2 * i) v[i] = limit;
}
return v;
} </cpp>
Código Postfix (não optimizado)
O código Postfix correspondente à função é o seguinte (agradece-se a comunicação de questões relativas a este código).
No código Postfix, BB# significa "bloco básico número".
| Postfix code |
|---|
| {{{2}}} |
Compiling and Running
Para compilar o código Postfix directamente, pode ser utilizada a ferramenta pf2asm (assumindo uma arquitectura de 32 bits):
pf2asm forall.pf yasm -felf forall.asm