src/mesa/slang/slang_label.c

   1
   2
   3 /**
   4  * Functions for managing instruction labels.
   5  * Basically, this is used to manage the problem of forward branches where
   6  * we have a branch instruciton but don't know the target address yet.
   7  */
   8
   9
  10 #include "main/mtypes.h"
  11 #include "program/prog_instruction.h"
  12 #include "slang_label.h"
  13 #include "slang_mem.h"
  14
  15
  16
  17 slang_label *
  18 _slang_label_new(const char *name)
  19 {
  20    slang_label *l = (slang_label *) _slang_alloc(sizeof(slang_label));
  21    if (l) {
  22       l->Name = _slang_strdup(name);
  23       l->Location = -1;
  24    }
  25    return l;
  26 }
  27
  28 /**
  29  * As above, but suffix the name with a unique number.
  30  */
  31 slang_label *
  32 _slang_label_new_unique(const char *name)
  33 {
  34    static int id = 1;
  35    slang_label *l = (slang_label *) _slang_alloc(sizeof(slang_label));
  36    if (l) {
  37       l->Name = (char *) _slang_alloc(strlen(name) + 10);
  38       if (!l->Name) {
  39          free(l);
  40          return NULL;
  41       }
  42       _mesa_snprintf(l->Name, strlen(name) + 10, "%s_%d", name, id);
  43       id++;
  44       l->Location = -1;
  45    }
  46    return l;
  47 }
  48
  49 void
  50 _slang_label_delete(slang_label *l)
  51 {
  52    if (l->Name) {
  53       _slang_free(l->Name);
  54       l->Name = NULL;
  55    }
  56    if (l->References) {
  57       _slang_free(l->References);
  58       l->References = NULL;
  59    }
  60    _slang_free(l);
  61 }
  62
  63
  64 void
  65 _slang_label_add_reference(slang_label *l, GLuint inst)
  66 {
  67    const GLuint oldSize = l->NumReferences * sizeof(GLuint);
  68    assert(l->Location < 0);
  69    l->References = _slang_realloc(l->References,
  70                                   oldSize, oldSize + sizeof(GLuint));
  71    if (l->References) {
  72       l->References[l->NumReferences] = inst;
  73       l->NumReferences++;
  74    }
  75 }
  76
  77
  78 GLint
  79 _slang_label_get_location(const slang_label *l)
  80 {
  81    return l->Location;
  82 }
  83
  84
  85 void
  86 _slang_label_set_location(slang_label *l, GLint location,
  87                           struct gl_program *prog)
  88 {
  89    GLuint i;
  90
  91    assert(l->Location < 0);
  92    assert(location >= 0);
  93
  94    l->Location = location;
  95
  96    /* for the instructions that were waiting to learn the label's location: */
  97    for (i = 0; i < l->NumReferences; i++) {
  98       const GLuint j = l->References[i];
  99       prog->Instructions[j].BranchTarget = location;
 100    }
 101
 102    if (l->References) {
 103       _slang_free(l->References);
 104       l->References = NULL;
 105    }
 106 }