From: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
Date: Thu, 17 Jan 2019 18:54:20 +0000 (+0100)
Subject: nir: Account for atomics in copy propagation.
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=8424cd8fbd1671c4c13f57cfa34bf8145d0fffcf;p=mesa.git

nir: Account for atomics in copy propagation.

Otherwise writes get propagated across atomics if no barrier is
used. Without barrier writes should still be visible in the same
invocation, so an atomic has to be considered a write.

CC: <mesa-stable@lists.freedesktop.org>
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Fixes: b3c61469255 "nir: Copy propagation between blocks"
Fixes: 62332d139c8 "nir: Add a local variable-based copy propagation pass"
---

diff --git a/src/compiler/nir/nir_opt_copy_prop_vars.c b/src/compiler/nir/nir_opt_copy_prop_vars.c
index 3dc0ad80573..8a5e1155082 100644
--- a/src/compiler/nir/nir_opt_copy_prop_vars.c
+++ b/src/compiler/nir/nir_opt_copy_prop_vars.c
@@ -157,9 +157,19 @@ gather_vars_written(struct copy_prop_var_state *state,
             written->modes = nir_var_shader_out;
             break;
 
+         case nir_intrinsic_deref_atomic_add:
+         case nir_intrinsic_deref_atomic_imin:
+         case nir_intrinsic_deref_atomic_umin:
+         case nir_intrinsic_deref_atomic_imax:
+         case nir_intrinsic_deref_atomic_umax:
+         case nir_intrinsic_deref_atomic_and:
+         case nir_intrinsic_deref_atomic_or:
+         case nir_intrinsic_deref_atomic_xor:
+         case nir_intrinsic_deref_atomic_exchange:
+         case nir_intrinsic_deref_atomic_comp_swap:
          case nir_intrinsic_store_deref:
          case nir_intrinsic_copy_deref: {
-            /* Destination in _both_ store_deref and copy_deref is src[0]. */
+            /* Destination in all of store_deref, copy_deref and the atomics is src[0]. */
             nir_deref_instr *dst = nir_src_as_deref(intrin->src[0]);
 
             uintptr_t mask = intrin->intrinsic == nir_intrinsic_store_deref ?
@@ -770,6 +780,19 @@ copy_prop_vars_block(struct copy_prop_var_state *state,
          break;
       }
 
+      case nir_intrinsic_deref_atomic_add:
+      case nir_intrinsic_deref_atomic_imin:
+      case nir_intrinsic_deref_atomic_umin:
+      case nir_intrinsic_deref_atomic_imax:
+      case nir_intrinsic_deref_atomic_umax:
+      case nir_intrinsic_deref_atomic_and:
+      case nir_intrinsic_deref_atomic_or:
+      case nir_intrinsic_deref_atomic_xor:
+      case nir_intrinsic_deref_atomic_exchange:
+      case nir_intrinsic_deref_atomic_comp_swap:
+         kill_aliases(copies, nir_src_as_deref(intrin->src[0]), 0xf);
+         break;
+
       default:
          break;
       }