+++ /dev/null
-/* optomizer.c
- *
- * (C) Copyright Jul 27 1996, Edmond J. Breen.
- * ALL RIGHTS RESERVED.
- * This code may be copied for personal, non-profit use only.
- *
- */
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-
-#include "MachSet.h"
-#include "global.h"
-#include "typesets.h"
-#include "error.h"
-
-#define isgoto(C,i) (opcode(C,i) >= jmpu && opcode(C,i) <= jmpTptr)
-
-typedef struct {
- int ninst; /* # of instructions */
- int leader; /* block leader */
- int nb; /* number of braches leading from block */
- int *branch; /* branch leaders */
-}block_t;
-
-#define crt_block() (block_t*)calloc(sizeof(block_t),1)
-
-#define addbranch(x,y,z) do{\
- x = (int*)realloc(x,(y+1)*sizeof(int));\
- x[y++] = z;\
- }while(0)
-
-static void freeblock(block_t * b, int nb)
-{
- int i;
- for(i =0;i<nb;++i)
- if(b[i].branch)
- free(b[i].branch);
- free(b);
-}
-
-static block_t initblock(code_t *c, int leader, int *visit)
-{
- int i;
- block_t b;
- b.leader = leader;
- b.branch = NULL;
- b.nb = 0;
- b.ninst = 0;
-
- for(i=leader;i<nextinst(c);++i) {
- visit[i]++;
- b.ninst++;
- if(opcode(c,i) == eicreturn)
- break;
- else if(isgoto(c,i)) {
- /*printf("[%d:%d]\n",i,i+ivalcode(c,i));*/
- addbranch(b.branch,b.nb,i+ivalcode(c,i));
- if(opcode(c,i) != jmpu) {
- /*printf("[%d:%d]\n",i,i+1);*/
- addbranch(b.branch,b.nb,i+1);
- }
- break;
- } else if(opcode(c,i) == jmptab) {
- struct {int n;val_t *loc;} *p;
- int j;
- p = pvalcode(c,i);
- addbranch(b.branch,b.nb,i + p->loc[0].ival);
- for(j =1;j<p->n;j+=2)
- addbranch(b.branch,b.nb,i + p->loc[j+1].ival);
- break;
- }
- }
- if(leader == nextinst(c))
- visit[leader]++;
- return b;
-}
-
-
-void EiC_peephole(code_t *C, int *visit)
-{
- int i, n,j;
- n = nextinst(C);
- for(i = 0; i < n; ++i)
- if(isgoto(C,i)) {
- j = i + ivalcode(C,i);
- if(j >= n)
- continue;
- if(opcode(C,j) == jmpu || opcode(C,i) == opcode(C,j)) {
- /*visit[i+ivalcode(C,i)]--;*/
- ivalcode(C,i) += ivalcode(C,j);
-
- }
- }
-}
-
-int EiC_analyseCode(code_t *C)
-{
- /* returns the index to the last visited instruction */
- block_t *block = NULL;
-
- int nb = 0;
- int i,j,rtn;
- int *visit;
-
- visit = calloc(sizeof(*visit),nextinst(C)+1);
- block = realloc(block,(nb+1)*sizeof(*block));
- block[nb++] = initblock(C,0,visit);
-
- for(i=0;i<nb;++i) {
- for(j=0;j<block[i].nb;++j) {
- if(!visit[block[i].branch[j]]) {
- block = realloc(block,(nb+1)*sizeof(*block));
- block[nb++] = initblock(C,block[i].branch[j],visit);
- } else
- visit[block[i].branch[j]]++;
- }
- }
-
- rtn = 0;
- for(i=0;i<=nextinst(C);)
- if(visit[i])
- rtn = i++;
- else if(i < nextinst(C) && instline(C,i)) {
- EiC_warningerror("Unreachable code at line %d",instline(C,i));
- for(;i<nextinst(C) && !visit[i];i++)
- ;
- } else
- i++;
-
- EiC_peephole(C,visit);
-
-/*******
- for(i=0;i<nextinst(C);++i)
- if(!visit[i])
- setopcode(C,i,empty);
-*******/
-
- freeblock(block,nb);
- free(visit);
-
-
- return rtn;
-}
-
-
-int EiC_checkPeepHole(token_t *e1,int op)
-{
- /*
- * A simple arithmetic optimizer:
- * do not add or subtract 0
- * and do not multiply or divide by 1
- */
- int v = 0;
- if (isconst(e1->Type)) {
- if (op == '+' || op == '-')
- switch (EiC_gettype(e1->Type)) {
- CASE_INT: CASE_UINT:v = e1->Val.ival == 0;
- break;
- CASE_LONG: CASE_ULONG:v = e1->Val.lval == 0;
- break;
- CASE_FLOAT:v = e1->Val.dval == 0;
- break;
- }
- else if (op == '*')
- switch (EiC_gettype(e1->Type)) {
- CASE_INT: CASE_UINT:v = e1->Val.ival == 1;
- break;
- CASE_LONG: CASE_ULONG:v = e1->Val.lval == 1;
- break;
- CASE_FLOAT:v = e1->Val.dval == 1;
- break;
- }
- }
- return v;
-}
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projects / opencv / blobdiff