glsl: replace assertion with conditional in _slang_pop_var_table()
We were hitting the assertion when we ran out of registers, which can happen.
Also, add some additional assertions and freshen up some comments.
diff --git a/src/mesa/shader/slang/slang_vartable.c b/src/mesa/shader/slang/slang_vartable.c
index de0c939..3649bdf 100644
--- a/src/mesa/shader/slang/slang_vartable.c
+++ b/src/mesa/shader/slang/slang_vartable.c
@@ -72,9 +72,8 @@
/**
- * Create new table, put at head, return ptr to it.
- * XXX we should take a maxTemps parameter to indicate how many temporaries
- * are available for the current shader/program target.
+ * Create new table on top of vartable stack.
+ * Used when we enter a {} block.
*/
void
_slang_push_var_table(slang_var_table *vt)
@@ -95,7 +94,8 @@
/**
- * Destroy given table, return ptr to Parent
+ * Pop top entry from variable table.
+ * Used when we leave a {} block.
*/
void
_slang_pop_var_table(slang_var_table *vt)
@@ -125,10 +125,12 @@
else
comp = 0;
- assert(store->Index >= 0);
- for (j = 0; j < store->Size; j++) {
- assert(t->Temps[store->Index * 4 + j + comp] == VAR);
- t->Temps[store->Index * 4 + j + comp] = FREE;
+ /* store->Index may be -1 if we run out of registers */
+ if (store->Index >= 0) {
+ for (j = 0; j < store->Size; j++) {
+ assert(t->Temps[store->Index * 4 + j + comp] == VAR);
+ t->Temps[store->Index * 4 + j + comp] = FREE;
+ }
}
store->Index = -1;
}
@@ -156,7 +158,7 @@
/**
- * Add a new variable to the given symbol table.
+ * Add a new variable to the given var/symbol table.
*/
void
_slang_add_variable(slang_var_table *vt, slang_variable *v)
@@ -214,6 +216,7 @@
for (i = 0; i <= vt->MaxRegisters * 4 - size; i += step) {
GLuint found = 0;
for (j = 0; j < (GLuint) size; j++) {
+ assert(i + j < 4 * MAX_PROGRAM_TEMPS);
if (i + j < vt->MaxRegisters * 4 && t->Temps[i + j] == FREE) {
found++;
}
@@ -225,13 +228,17 @@
/* found block of size free regs */
if (size > 1)
assert(i % 4 == 0);
- for (j = 0; j < (GLuint) size; j++)
+ for (j = 0; j < (GLuint) size; j++) {
+ assert(i + j < 4 * MAX_PROGRAM_TEMPS);
t->Temps[i + j] = isTemp ? TEMP : VAR;
+ }
assert(i < MAX_PROGRAM_TEMPS * 4);
t->ValSize[i] = size;
return i;
}
}
+
+ /* if we get here, we ran out of registers */
return -1;
}