Mesa (master): intel/compiler/fs: Fix application of cmod and saturate to LINE/MAC pair

[Matt Turner]

Module: Mesa
Branch: master
Commit: b1afdf9fc121df7e2e757fb9cf0d2c1f37a408ba
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=b1afdf9fc121df7e2e757fb9cf0d2c1f37a408ba

Author: Matt Turner <mattst88 at gmail.com>
Date:   Wed Jun 14 14:47:19 2017 -0700

intel/compiler/fs: Fix application of cmod and saturate to LINE/MAC pair

This isn't technically broken, but the next patch will make this
function report whether it generated multiple instructions, and that
information will be used to disable the application of conditional mod
by the generic code.

Reviewed-by: Kenneth Graunke <kenneth at whitecape.org>

---

 src/intel/compiler/brw_fs_generator.cpp | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/src/intel/compiler/brw_fs_generator.cpp b/src/intel/compiler/brw_fs_generator.cpp
index cd5be054f6..bba917d755 100644
--- a/src/intel/compiler/brw_fs_generator.cpp
+++ b/src/intel/compiler/brw_fs_generator.cpp
@@ -673,13 +673,22 @@ fs_generator::generate_linterp(fs_inst *inst,
    struct brw_reg delta_x = src[0];
    struct brw_reg delta_y = offset(src[0], inst->exec_size / 8);
    struct brw_reg interp = src[1];
+   brw_inst *i[2];
 
    if (devinfo->has_pln &&
        (devinfo->gen >= 7 || (delta_x.nr & 1) == 0)) {
       brw_PLN(p, dst, interp, delta_x);
    } else {
-      brw_LINE(p, brw_null_reg(), interp, delta_x);
-      brw_MAC(p, dst, suboffset(interp, 1), delta_y);
+      i[0] = brw_LINE(p, brw_null_reg(), interp, delta_x);
+      i[1] = brw_MAC(p, dst, suboffset(interp, 1), delta_y);
+
+      brw_inst_set_cond_modifier(p->devinfo, i[1], inst->conditional_mod);
+
+      /* brw_set_default_saturate() is called before emitting instructions, so
+       * the saturate bit is set in each instruction, so we need to unset it on
+       * the first instruction.
+       */
+      brw_inst_set_saturate(p->devinfo, i[0], false);
    }
 }