mesa: check/prevent NaN for EX2/LG2
diff --git a/src/mesa/shader/prog_execute.c b/src/mesa/shader/prog_execute.c
index 68a5935..2b7237e 100644
--- a/src/mesa/shader/prog_execute.c
+++ b/src/mesa/shader/prog_execute.c
@@ -832,10 +832,14 @@
break;
case OPCODE_EX2: /* Exponential base 2 */
{
- GLfloat a[4], result[4];
+ GLfloat a[4], result[4], val;
fetch_vector1(&inst->SrcReg[0], machine, a);
- result[0] = result[1] = result[2] = result[3] =
- (GLfloat) _mesa_pow(2.0, a[0]);
+ val = (GLfloat) _mesa_pow(2.0, a[0]);
+ /*
+ if (IS_INF_OR_NAN(val))
+ val = 1.0e10;
+ */
+ result[0] = result[1] = result[2] = result[3] = val;
store_vector4(inst, machine, result);
}
break;
@@ -911,12 +915,17 @@
break;
case OPCODE_LG2: /* log base 2 */
{
- GLfloat a[4], result[4];
+ GLfloat a[4], result[4], val;
fetch_vector1(&inst->SrcReg[0], machine, a);
/* The fast LOG2 macro doesn't meet the precision requirements.
*/
- result[0] = result[1] = result[2] = result[3] =
- (log(a[0]) * 1.442695F);
+ if (a[0] == 0.0F) {
+ val = 0.0F;
+ }
+ else {
+ val = log(a[0]) * 1.442695F;
+ }
+ result[0] = result[1] = result[2] = result[3] = val;
store_vector4(inst, machine, result);
}
break;