dataflow.c

   1
   2 #include "code.h"
   3 #include "utils.h"
   4
   5 const uint32 regmask_localvars[NUM_REGMASK] = { 0x43FFFFFE, 0x00000000 };
   6
   7 static
   8 void mark_ssavar (struct ssavar *var, enum ssavartype type, int num)
   9 {
  10   element useel, phiel;
  11   struct value *val;
  12
  13   var->info = num;
  14   var->type = type;
  15   useel = list_head (var->uses);
  16   while (useel) {
  17     struct operation *use = element_getvalue (useel);
  18     if (use->type == OP_PHI) {
  19       phiel = list_head (use->operands);
  20       while (phiel) {
  21         struct value *val = element_getvalue (phiel);
  22         if (val->val.variable->type == SSAVAR_UNK) {
  23           mark_ssavar (val->val.variable, type, num);
  24         }
  25         phiel = element_next (phiel);
  26       }
  27       val = list_headvalue (use->results);
  28       if (val->val.variable->type == SSAVAR_UNK)
  29         mark_ssavar (val->val.variable, type, num);
  30     }
  31     useel = element_next (useel);
  32   }
  33
  34   if (var->def->type == OP_PHI) {
  35     phiel = list_head (var->def->operands);
  36     while (phiel) {
  37       struct value *val = element_getvalue (phiel);
  38       if (val->val.variable->type == SSAVAR_UNK) {
  39         mark_ssavar (val->val.variable, type, num);
  40       }
  41       phiel = element_next (phiel);
  42     }
  43   }
  44 }
  45
  46 void extract_variables (struct subroutine *sub)
  47 {
  48   element varel;
  49   int count = 0;
  50
  51   varel = list_head (sub->ssavars);
  52   while (varel) {
  53     struct ssavar *var = element_getvalue (varel);
  54     if (var->type == SSAVAR_UNK) {
  55       if (IS_BIT_SET (regmask_localvars, var->name.val.intval)) {
  56         if (var->def->type == OP_START) {
  57           mark_ssavar (var, SSAVAR_ARGUMENT, var->name.val.intval);
  58         } else if (var->def->type == OP_CALL && var->name.val.intval != REGISTER_GPR_V0 &&
  59                    var->name.val.intval != REGISTER_GPR_V1) {
  60           var->type = SSAVAR_INVALID;
  61         } else {
  62           int istemp = FALSE;
  63
  64           if (list_size (var->uses) <= 1) {
  65             struct operation *op = list_headvalue (var->uses);
  66             if (op) {
  67               if (op->type != OP_PHI)
  68                 istemp = TRUE;
  69             } else {
  70               istemp = TRUE;
  71             }
  72           }
  73
  74           if (var->def->type == OP_MOVE || var->def->type == OP_INSTRUCTION) {
  75             if (var->def->type == OP_INSTRUCTION) {
  76               if (var->def->info.iop.loc->insn->flags & (INSN_LOAD | INSN_STORE | INSN_BRANCH))
  77                 istemp = FALSE;
  78             }
  79           } else {
  80             istemp = FALSE;
  81           }
  82
  83           if (istemp) {
  84             var->def->status |= OPERATION_DEFERRED;
  85             var->type = SSAVAR_TEMP;
  86             var->info = 0;
  87           } else {
  88             mark_ssavar (var, SSAVAR_LOCAL, ++count);
  89           }
  90         }
  91       } else {
  92         var->type = SSAVAR_ARGUMENT;
  93       }
  94     }
  95     varel = element_next (varel);
  96   }
  97 }