i965/fs: Invert if-condition for nir_op_inotexperiments

1 files changed, 27 insertions, 4 deletions

diff --git a/src/intel/compiler/brw_fs_nir.cpp b/src/intel/compiler/brw_fs_nir.cpp
index a41dc2a47b8..113678ba0ff 100644
--- a/src/intel/compiler/brw_fs_nir.cpp
+++ b/src/intel/compiler/brw_fs_nir.cpp
@@ -390,13 +390,36 @@ fs_visitor::nir_emit_cf_list(exec_list *list)
 void
 fs_visitor::nir_emit_if(nir_if *if_stmt)
 {
+   fs_inst *inst = NULL;
+   bool invert = false;
+
    /* first, put the condition into f0 */
-   fs_inst *inst = bld.MOV(bld.null_reg_d(),
-                            retype(get_nir_src(if_stmt->condition),
-                                   BRW_REGISTER_TYPE_D));
+   if (if_stmt->condition.is_ssa &&
+       if_stmt->condition.ssa->parent_instr->type == nir_instr_type_alu) {
+      nir_alu_instr *const cond =
+         nir_instr_as_alu(if_stmt->condition.ssa->parent_instr);
+
+      /* FINISHME: Care about swizzle here? */
+      if (cond->op == nir_op_inot &&
+          !cond->src[0].negate &&
+          !cond->src[0].abs) {
+         inst = bld.MOV(bld.null_reg_d(),
+                        retype(get_nir_src(cond->src[0].src),
+                               BRW_REGISTER_TYPE_D));
+
+         invert = true;
+      }
+   }
+
+   if (inst == NULL) {
+      inst = bld.MOV(bld.null_reg_d(),
+                     retype(get_nir_src(if_stmt->condition),
+                            BRW_REGISTER_TYPE_D));
+   }
+
    inst->conditional_mod = BRW_CONDITIONAL_NZ;
 
-   bld.IF(BRW_PREDICATE_NORMAL);
+   bld.IF(BRW_PREDICATE_NORMAL)->predicate_inverse = invert;
 
    nir_emit_cf_list(&if_stmt->then_list);