aco/spill: Fix spilling of Phi operands

By adding the renamed variable, phi operands got spilled twice at the precessors.

Fixes: dEQP-VK.ray_query.misc.dynamic_indexing
Closes: #7493
Cc: mesa-stable
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/19109>
(cherry picked from commit ebf7f7a182)

.pick_status.json

@@ -13,7 +13,7 @@
         "description": "aco/spill: Fix spilling of Phi operands",
         "nominated": true,
         "nomination_type": 0,
-        "resolution": 0,
+        "resolution": 1,
         "main_sha": null,
         "because_sha": null
     },

src/amd/compiler/aco_spill.cpp

@@ -920,8 +920,10 @@ add_coupling_code(spill_ctx& ctx, Block* block, unsigned block_idx)
                   pred.instructions[idx]->opcode != aco_opcode::p_logical_end);
          std::vector<aco_ptr<Instruction>>::iterator it = std::next(pred.instructions.begin(), idx);
          pred.instructions.insert(it, std::move(spill));
+
+         /* Add the original name to predecessor's spilled variables */
          if (spill_op.isTemp())
-            ctx.spills_exit[pred_idx][spill_op.getTemp()] = spill_id;
+            ctx.spills_exit[pred_idx][phi->operands[i].getTemp()] = spill_id;
       }
 
       /* remove phi from instructions */