src/mesa/shader/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 "slang_label.h"
  11 #include "slang_mem.h"
  12
  13
  14
  15 slang_label *
  16 _slang_label_new(const char *name)
  17 {
  18    slang_label *l = (slang_label *) _slang_alloc(sizeof(slang_label));
  19    if (l) {
  20       l->Name = _slang_strdup(name);
  21       l->Location = -1;
  22    }
  23    return l;
  24 }
  25
  26 /**
  27  * As above, but suffix the name with a unique number.
  28  */
  29 slang_label *
  30 _slang_label_new_unique(const char *name)
  31 {
  32    static int id = 1;
  33    slang_label *l = (slang_label *) _slang_alloc(sizeof(slang_label));
  34    if (l) {
  35       l->Name = (char *) _slang_alloc(_mesa_strlen(name) + 10);
  36       if (!l->Name) {
  37          _mesa_free(l);
  38          return NULL;
  39       }
  40       _mesa_sprintf(l->Name, "%s_%d", name, id);
  41       id++;
  42       l->Location = -1;
  43    }
  44    return l;
  45 }
  46
  47 void
  48 _slang_label_delete(slang_label *l)
  49 {
  50    if (l->Name) {
  51       _slang_free(l->Name);
  52       l->Name = NULL;
  53    }
  54    if (l->References) {
  55       _slang_free(l->References);
  56       l->References = NULL;
  57    }
  58    _slang_free(l);
  59 }
  60
  61
  62 void
  63 _slang_label_add_reference(slang_label *l, GLuint inst)
  64 {
  65    const GLuint oldSize = l->NumReferences * sizeof(GLuint);
  66    assert(l->Location < 0);
  67    l->References = _slang_realloc(l->References,
  68                                   oldSize, oldSize + sizeof(GLuint));
  69    if (l->References) {
  70       l->References[l->NumReferences] = inst;
  71       l->NumReferences++;
  72    }
  73 }
  74
  75
  76 GLint
  77 _slang_label_get_location(const slang_label *l)
  78 {
  79    return l->Location;
  80 }
  81
  82
  83 void
  84 _slang_label_set_location(slang_label *l, GLint location,
  85                           struct gl_program *prog)
  86 {
  87    GLuint i;
  88
  89    assert(l->Location < 0);
  90    assert(location >= 0);
  91
  92    l->Location = location;
  93
  94    /* for the instructions that were waiting to learn the label's location: */
  95    for (i = 0; i < l->NumReferences; i++) {
  96       const GLuint j = l->References[i];
  97       prog->Instructions[j].BranchTarget = location;
  98    }
  99
 100    if (l->References) {
 101       _slang_free(l->References);
 102       l->References = NULL;
 103    }
 104 }