r600g: Fix special negative immediate constants when using ABS modifier.

Some constants (like 1.0 and 0.5) could be inlined as immediate inputs
without using their literal value. The r600_bytecode_special_constants()
function emulates the negative of these constants by using NEG modifier.

However some shaders define -1.0 constant and want to use it as 1.0.
They do so by using ABS modifier. But r600_bytecode_special_constants()
set NEG in addition to ABS. Since NEG modifier have priority over ABS one,
we get -|1.0| as result, instead of |1.0|.

The patch simply prevents the additional switching of NEG when ABS is set.

[According to Ivan Kalvachev, this bug was fond via
https://github.com/iXit/Mesa-3D/issues/126 and
https://github.com/iXit/Mesa-3D/issues/127]

Signed-off-by: Ivan Kalvachev <ikalvachev@gmail.com>
Reviewed-by: Nicolai Hähnle <nicolai.haehnle@amd.com>
CC: <mesa-stable@lists.freedesktop.org>
This commit is contained in:
Ivan Kalvachev
2015-10-25 01:16:58 +03:00
committed by Nicolai Hähnle
parent 24c90888ae
commit f75f21a24a
3 changed files with 6 additions and 6 deletions

View File

@@ -635,7 +635,7 @@ static int replace_gpr_with_pv_ps(struct r600_bytecode *bc,
return 0;
}
void r600_bytecode_special_constants(uint32_t value, unsigned *sel, unsigned *neg)
void r600_bytecode_special_constants(uint32_t value, unsigned *sel, unsigned *neg, unsigned abs)
{
switch(value) {
case 0:
@@ -655,11 +655,11 @@ void r600_bytecode_special_constants(uint32_t value, unsigned *sel, unsigned *ne
break;
case 0xBF800000: /* -1.0f */
*sel = V_SQ_ALU_SRC_1;
*neg ^= 1;
*neg ^= !abs;
break;
case 0xBF000000: /* -0.5f */
*sel = V_SQ_ALU_SRC_0_5;
*neg ^= 1;
*neg ^= !abs;
break;
default:
*sel = V_SQ_ALU_SRC_LITERAL;
@@ -1208,7 +1208,7 @@ int r600_bytecode_add_alu_type(struct r600_bytecode *bc,
}
if (nalu->src[i].sel == V_SQ_ALU_SRC_LITERAL)
r600_bytecode_special_constants(nalu->src[i].value,
&nalu->src[i].sel, &nalu->src[i].neg);
&nalu->src[i].sel, &nalu->src[i].neg, nalu->src[i].abs);
}
if (nalu->dst.sel >= bc->ngpr) {
bc->ngpr = nalu->dst.sel + 1;