[Nouveau] [PATCH] nv50/ir: avoid creating instructions that can't be emitted

[Ilia Mirkin]

When constant folding a MAD operation, we first fold the multiply and
generate an ADD. However we do so without making sure that the immediate
can be handled in the saturate case. If it can't, load the immediate in
a separate instruction.

Reported-by: Tiziano Bacocco <tizbac2 at gmail.com>
Signed-off-by: Ilia Mirkin <imirkin at alum.mit.edu>
Cc: "10.2 10.3" <mesa-stable at lists.freedesktop.org>
---
 src/gallium/drivers/nouveau/codegen/nv50_ir_peephole.cpp | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/gallium/drivers/nouveau/codegen/nv50_ir_peephole.cpp b/src/gallium/drivers/nouveau/codegen/nv50_ir_peephole.cpp
index 1a9a25f..719f980 100644
--- a/src/gallium/drivers/nouveau/codegen/nv50_ir_peephole.cpp
+++ b/src/gallium/drivers/nouveau/codegen/nv50_ir_peephole.cpp
@@ -567,6 +567,10 @@ ConstantFolding::expr(Instruction *i,
       ImmediateValue src0;
       if (i->src(0).getImmediate(src0))
          expr(i, src0, *i->getSrc(1)->asImm());
+      if (i->saturate && !prog->getTarget()->isSatSupported(i)) {
+         bld.setPosition(i, false);
+         i->setSrc(1, bld.loadImm(NULL, res.data.u32));
+      }
    } else {
       i->op = i->saturate ? OP_SAT : OP_MOV; /* SAT handled by unary() */
    }
-- 
1.8.5.5