Code Generation/Exercise 11: Difference between revisions

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< Code Generation
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ALIGN
ALIGN
LABEL limit ; not really this name
LABEL limit ; not really this name
CONST 1024
SINT 1024
; done - go back to code segment
; done - go back to code segment
TEXT
TEXT
Line 40: Line 40:
INT 0
INT 0
LOCAL -4
LOCAL -4
STORE ; i = 0
STINT ; i = 0


; for-loop test
; for-loop test
LABEL fortest
LABEL fortest
LOCAL -4
LOCAL -4
LOAD ; i
LDINT ; i
ADDR limit
ADDR limit
LOAD ; limit
LDINT ; limit
LT ; i<limit
LT ; i<limit
JZ forend
JZ forend
Line 58: Line 58:
INT 3
INT 3
LOCAL -4 ; &i
LOCAL -4 ; &i
LOAD ; i
LDINT ; i
MUL
MUL
INT 8 ; sizeof(double)
INT 8 ; sizeof(double)
Line 64: Line 64:
I2D
I2D


DDUP ; implement assignment value
DUP64 ; implement assignment value


; compute &v[i] == v+i*sizeof(double)
; compute &v[i] == v+i*sizeof(double)
LOCAL +8 ; &v
LOCAL +8 ; &v
LOAD ; v
LDINT ; v
LOCAL -4 ; &i
LOCAL -4 ; &i
LOAD ; i
LDINT ; i
INT 8 ; sizeof(double)
INT 8 ; sizeof(double)
MUL
MUL
ADD ; &v[i]
ADD ; &v[i]


DSTORE ; do assignment of double value
STDOUBLE ; do assignment of double value


TRASH 8 ; discard value of assignment
TRASH 8 ; discard value of assignment
Line 84: Line 84:
; compute &v[i] == v+i*sizeof(double)
; compute &v[i] == v+i*sizeof(double)
LOCAL +8 ; &v
LOCAL +8 ; &v
LOAD ; v
LDINT ; v
LOCAL -4 ; &i
LOCAL -4 ; &i
LOAD ; i
LDINT ; i
INT 8 ; sizeof(double)
INT 8 ; sizeof(double)
MUL
MUL
ADD ; &v[i]
ADD ; &v[i]
DLOAD ; v[i]
LDDOUBLE ; v[i]


; compute and promote 2*i
; compute and promote 2*i
INT 2
INT 2
LOCAL -4 ; &i
LOCAL -4 ; &i
LOAD ; i
LDINT ; i
MUL
MUL
I2D
I2D
Line 112: Line 112:
; load and promote "limit"
; load and promote "limit"
ADDR limit
ADDR limit
LOAD
LDINT
I2D
I2D


Line 119: Line 119:
; compute &v[i] == v+i*sizeof(double)
; compute &v[i] == v+i*sizeof(double)
LOCAL +8 ; &v
LOCAL +8 ; &v
LOAD ; v
LDINT ; v
LOCAL -4 ; &i
LOCAL -4 ; &i
LOAD ; i
LDINT ; i
INT 8 ; sizeof(double)
INT 8 ; sizeof(double)
MUL
MUL
ADD ; &v[i]
ADD ; &v[i]


DSTORE ; do  assignment of double value
STDOUBLE ; do  assignment of double value


TRASH 8 ; discard value of assignment
TRASH 8 ; discard value of assignment
Line 138: Line 138:
; increment expression
; increment expression
LOCAL -4 ; &i
LOCAL -4 ; &i
LOAD ; i
LDINT ; i
DUP
DUP32
INT 1
INT 1
ADD
ADD
LOCAL -4 ; &i
LOCAL -4 ; &i
STORE
STINT
TRASH 4
TRASH 4


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; return *v
; return *v
LOCAL +8 ; &v
LOCAL +8 ; &v
LOAD ; v
LDINT ; v
DLOAD ; *v
LDDOUBLE ; *v
DPOP
STFVAL64
LEAVE
LEAVE
RET
RET

Revision as of 22:55, 1 May 2018

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
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