Mesa (master): nir: move getting deref from var after we check deref type.

[GitLab Mirror]

Module: Mesa
Branch: master
Commit: 760859cac219d9ea4d29f58351161ea8de0bcc44
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=760859cac219d9ea4d29f58351161ea8de0bcc44

Author: Dave Airlie <airlied at redhat.com>
Date:   Mon Nov 19 13:51:48 2018 +1000

nir: move getting deref from var after we check deref type.

I posted a load of hacks before to do this, Jason suggested this,
just check the deref mode, not the variable mode and delay getting
the variable until we know the type.

avoids crashes when derefing shared memory pointers.

Reviewed-by: Jason Ekstrand <jason at jlekstrand.net>

---

 src/compiler/nir/nir_gather_info.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/src/compiler/nir/nir_gather_info.c b/src/compiler/nir/nir_gather_info.c
index 15d38f036b..7eaa4c27c1 100644
--- a/src/compiler/nir/nir_gather_info.c
+++ b/src/compiler/nir/nir_gather_info.c
@@ -210,10 +210,9 @@ gather_intrinsic_info(nir_intrinsic_instr *instr, nir_shader *shader,
    case nir_intrinsic_load_deref:
    case nir_intrinsic_store_deref:{
       nir_deref_instr *deref = nir_src_as_deref(instr->src[0]);
-      nir_variable *var = nir_deref_instr_get_variable(deref);
-
-      if (var->data.mode == nir_var_shader_in ||
-          var->data.mode == nir_var_shader_out) {
+      if (deref->mode == nir_var_shader_in ||
+          deref->mode == nir_var_shader_out) {
+         nir_variable *var = nir_deref_instr_get_variable(deref);
          bool is_output_read = false;
          if (var->data.mode == nir_var_shader_out &&
              instr->intrinsic == nir_intrinsic_load_deref)