[Mesa-dev] [PATCH 4/7] nir/lower_io_to_scalar: Look at derefs for modes

[Jason Ekstrand]

This is instead of looking all the way back to the variable which may
not exist for all derefs.  This makes this code properly ignore casts
with modes other than the mode[s] we care about (where casts aren't
allowed).
---
 src/compiler/nir/nir_lower_io_to_scalar.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/src/compiler/nir/nir_lower_io_to_scalar.c b/src/compiler/nir/nir_lower_io_to_scalar.c
index 929761fa888..d58805294b5 100644
--- a/src/compiler/nir/nir_lower_io_to_scalar.c
+++ b/src/compiler/nir/nir_lower_io_to_scalar.c
@@ -308,9 +308,12 @@ nir_lower_io_to_scalar_early(nir_shader *shader, nir_variable_mode mask)
                    intr->intrinsic != nir_intrinsic_interp_deref_at_offset)
                   continue;
 
-               nir_variable *var =
-                  nir_deref_instr_get_variable(nir_src_as_deref(intr->src[0]));
-               nir_variable_mode mode = var->data.mode;
+               nir_deref_instr *deref = nir_src_as_deref(intr->src[0]);
+               nir_variable_mode mode = deref->mode;
+               if (!(mode & mask))
+                  continue;
+
+               nir_variable *var = nir_deref_instr_get_variable(deref);
 
                /* TODO: add patch support */
                if (var->data.patch)
-- 
2.19.2