[Mesa-dev] [PATCH 03/45] st/nine: Fix rounding issue with vs1.1 a0 reg

[Axel Davy]

vs1.1 rounds a0 to lowest integer, while
other versions do round to closest.

To use the same path as the other versions (with ARR),
we were substracting 0.5 for vs1.1 to get round to lowest.

This gives wrong result if a0 is set to 0:
round(0 - 0.5) = -1

Instead just use ARL for vs1.1

Signed-off-by: Axel Davy <axel.davy at ens.fr>
Reviewed-by: Patrick Rudolph <siro at das-labor.org>
---
 src/gallium/state_trackers/nine/nine_shader.c | 29 +++++++--------------------
 1 file changed, 7 insertions(+), 22 deletions(-)

diff --git a/src/gallium/state_trackers/nine/nine_shader.c b/src/gallium/state_trackers/nine/nine_shader.c
index 7234003..5dcf39d 100644
--- a/src/gallium/state_trackers/nine/nine_shader.c
+++ b/src/gallium/state_trackers/nine/nine_shader.c
@@ -852,7 +852,12 @@ tx_src_param(struct shader_translator *tx, const struct sm1_src_param *param)
             /* the address register (vs only) must be
              * assigned before use */
             assert(!ureg_dst_is_undef(tx->regs.a0));
-            ureg_ARR(ureg, tx->regs.address, ureg_src(tx->regs.a0));
+            /* Round to lowest for vs1.1 (contrary to the doc), else
+             * round to nearest */
+            if (tx->version.major < 2 && tx->version.minor < 2)
+                ureg_ARL(ureg, tx->regs.address, ureg_src(tx->regs.a0));
+            else
+                ureg_ARR(ureg, tx->regs.address, ureg_src(tx->regs.a0));
             src = ureg_src(tx->regs.address);
         } else {
             if (tx->version.major < 2 && tx->version.minor < 4) {
@@ -1540,25 +1545,6 @@ DECL_SPECIAL(CALLNZ)
     return D3D_OK;
 }
 
-DECL_SPECIAL(MOV_vs1x)
-{
-    if (tx->insn.dst[0].file == D3DSPR_ADDR) {
-        /* Implementation note: We don't write directly
-         * to the addr register, but to an intermediate
-         * float register.
-         * Contrary to the doc, when writing to ADDR here,
-         * the rounding is not to nearest, but to lowest
-         * (wine test).
-         * Since we use ARR next, substract 0.5. */
-        ureg_SUB(tx->ureg,
-                 tx_dst_param(tx, &tx->insn.dst[0]),
-                 tx_src_param(tx, &tx->insn.src[0]),
-                 ureg_imm1f(tx->ureg, 0.5f));
-        return D3D_OK;
-    }
-    return NineTranslateInstruction_Generic(tx);
-}
-
 DECL_SPECIAL(LOOP)
 {
     struct ureg_program *ureg = tx->ureg;
@@ -2733,8 +2719,7 @@ DECL_SPECIAL(COMMENT)
 struct sm1_op_info inst_table[] =
 {
     _OPI(NOP, NOP, V(0,0), V(3,0), V(0,0), V(3,0), 0, 0, NULL), /* 0 */
-    _OPI(MOV, MOV, V(0,0), V(1,1), V(0,0), V(0,0), 1, 1, SPECIAL(MOV_vs1x)),
-    _OPI(MOV, MOV, V(2,0), V(3,0), V(0,0), V(3,0), 1, 1, NULL),
+    _OPI(MOV, MOV, V(0,0), V(3,0), V(0,0), V(3,0), 1, 1, NULL),
     _OPI(ADD, ADD, V(0,0), V(3,0), V(0,0), V(3,0), 1, 2, NULL), /* 2 */
     _OPI(SUB, SUB, V(0,0), V(3,0), V(0,0), V(3,0), 1, 2, NULL), /* 3 */
     _OPI(MAD, MAD, V(0,0), V(3,0), V(0,0), V(3,0), 1, 3, NULL), /* 4 */
-- 
2.7.0