Mesa (master): nir: Don' t try to to-SSA ALU instructions that are already SSA.

[Eric Anholt]

Module: Mesa
Branch: master
Commit: 9a3a60cb138ea9a7fb29368c8c8efe614a7d80fe
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=9a3a60cb138ea9a7fb29368c8c8efe614a7d80fe

Author: Eric Anholt <eric at anholt.net>
Date:   Mon Jan 26 14:37:42 2015 -0800

nir: Don't try to to-SSA ALU instructions that are already SSA.

Reviewed-by: Jason Ekstrand <jason.ekstrand at intel.com>

---

 src/glsl/nir/nir_to_ssa.c |    3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/glsl/nir/nir_to_ssa.c b/src/glsl/nir/nir_to_ssa.c
index 9c577fa..dbe1699 100644
--- a/src/glsl/nir/nir_to_ssa.c
+++ b/src/glsl/nir/nir_to_ssa.c
@@ -239,6 +239,9 @@ rewrite_alu_instr_forward(nir_alu_instr *instr, rewrite_state *state)
 
    nir_foreach_src(&instr->instr, rewrite_use, state);
 
+   if (instr->dest.dest.is_ssa)
+      return;
+
    nir_register *reg = instr->dest.dest.reg.reg;
    unsigned index = reg->index;