diff --git a/intern/cycles/kernel/integrator/integrator_volume_stack.h b/intern/cycles/kernel/integrator/integrator_volume_stack.h
index 5d11d6be04f..f7d86cf6040 100644
--- a/intern/cycles/kernel/integrator/integrator_volume_stack.h
+++ b/intern/cycles/kernel/integrator/integrator_volume_stack.h
@@ -167,7 +167,16 @@ ccl_device void volume_stack_init(INTEGRATOR_STATE_ARGS,
 }
 #endif
 
-ccl_device void volume_stack_enter_exit(INTEGRATOR_STATE_ARGS, const ShaderData *sd)
+template<typename ReadShaderProc,
+         typename ReadObjectProc,
+         typename WriteShaderProc,
+         typename WriteObjectProc>
+ccl_device void volume_stack_enter_exit_common(INTEGRATOR_STATE_ARGS,
+                                               const ShaderData *sd,
+                                               const ReadShaderProc &read_shader_proc,
+                                               const ReadObjectProc &read_object_proc,
+                                               const WriteShaderProc &write_shader_proc,
+                                               const WriteObjectProc &write_object_proc)
 {
   /* todo: we should have some way for objects to indicate if they want the
    * world shader to work inside them. excluding it by default is problematic
@@ -178,16 +187,14 @@ ccl_device void volume_stack_enter_exit(INTEGRATOR_STATE_ARGS, const ShaderData
 
   if (sd->flag & SD_BACKFACING) {
     /* Exit volume object: remove from stack. */
-    for (int i = 0; INTEGRATOR_STATE_ARRAY(volume_stack, i, shader) != SHADER_NONE; i++) {
-      if (INTEGRATOR_STATE_ARRAY(volume_stack, i, object) == sd->object) {
+    for (int i = 0; read_shader_proc(i) != SHADER_NONE; i++) {
+      if (read_object_proc(i) == sd->object) {
         /* Shift back next stack entries. */
         do {
-          INTEGRATOR_STATE_ARRAY_WRITE(volume_stack, i, shader) = INTEGRATOR_STATE_ARRAY(
-              volume_stack, i + 1, shader);
-          INTEGRATOR_STATE_ARRAY_WRITE(volume_stack, i, object) = INTEGRATOR_STATE_ARRAY(
-              volume_stack, i + 1, object);
+          write_shader_proc(i, read_shader_proc(i + 1));
+          write_object_proc(i, read_object_proc(i + 1));
           i++;
-        } while (INTEGRATOR_STATE_ARRAY(volume_stack, i, shader) != SHADER_NONE);
+        } while (read_shader_proc(i) != SHADER_NONE);
 
         return;
       }
@@ -197,9 +204,9 @@ ccl_device void volume_stack_enter_exit(INTEGRATOR_STATE_ARGS, const ShaderData
     /* Enter volume object: add to stack. */
     int i;
 
-    for (i = 0; INTEGRATOR_STATE_ARRAY(volume_stack, i, shader) != SHADER_NONE; i++) {
+    for (i = 0; read_shader_proc(i) != SHADER_NONE; i++) {
       /* Already in the stack? then we have nothing to do. */
-      if (INTEGRATOR_STATE_ARRAY(volume_stack, i, object) == sd->object) {
+      if (read_object_proc(i) == sd->object) {
         return;
       }
     }
@@ -210,58 +217,36 @@ ccl_device void volume_stack_enter_exit(INTEGRATOR_STATE_ARGS, const ShaderData
     }
 
     /* Add to the end of the stack. */
-    INTEGRATOR_STATE_ARRAY_WRITE(volume_stack, i, shader) = sd->shader;
-    INTEGRATOR_STATE_ARRAY_WRITE(volume_stack, i, object) = sd->object;
-    INTEGRATOR_STATE_ARRAY_WRITE(volume_stack, i + 1, shader) = SHADER_NONE;
+    write_shader_proc(i, sd->shader);
+    write_object_proc(i, sd->object);
+    write_shader_proc(i + 1, SHADER_NONE);
   }
 }
 
-ccl_device void shadow_volume_stack_enter_exit(INTEGRATOR_STATE_ARGS, const ShaderData *sd)
+ccl_device void volume_stack_enter_exit(INTEGRATOR_STATE_ARGS, const ShaderData *sd)
 {
-  /* Duplicate of volume_stack_enter_exit, unclear how to deduplicate
-   * in an elegant way. */
-  if (!(sd->flag & SD_HAS_VOLUME)) {
-    return;
-  }
-
-  if (sd->flag & SD_BACKFACING) {
-    /* Exit volume object: remove from stack. */
-    for (int i = 0; INTEGRATOR_STATE_ARRAY(shadow_volume_stack, i, shader) != SHADER_NONE; i++) {
-      if (INTEGRATOR_STATE_ARRAY(shadow_volume_stack, i, object) == sd->object) {
-        /* Shift back next stack entries. */
-        do {
-          INTEGRATOR_STATE_ARRAY_WRITE(shadow_volume_stack, i, shader) = INTEGRATOR_STATE_ARRAY(
-              shadow_volume_stack, i + 1, shader);
-          INTEGRATOR_STATE_ARRAY_WRITE(shadow_volume_stack, i, object) = INTEGRATOR_STATE_ARRAY(
-              shadow_volume_stack, i + 1, object);
-          i++;
-        } while (INTEGRATOR_STATE_ARRAY(shadow_volume_stack, i, shader) != SHADER_NONE);
-
-        return;
-      }
-    }
-  }
-  else {
-    /* Enter volume object: add to stack. */
-    int i;
-
-    for (i = 0; INTEGRATOR_STATE_ARRAY(shadow_volume_stack, i, shader) != SHADER_NONE; i++) {
-      /* Already in the stack? then we have nothing to do */
-      if (INTEGRATOR_STATE_ARRAY(shadow_volume_stack, i, object) == sd->object) {
-        return;
-      }
-    }
-
-    /* If we exceed the stack limit, ignore. */
-    if (i >= VOLUME_STACK_SIZE - 1) {
-      return;
-    }
+  volume_stack_enter_exit_common(
+      INTEGRATOR_STATE_PASS,
+      sd,
+      [=](int i) -> int { return INTEGRATOR_STATE_ARRAY(volume_stack, i, shader); },
+      [=](int i) -> int { return INTEGRATOR_STATE_ARRAY(volume_stack, i, object); },
+      [=](int i, int shader) { INTEGRATOR_STATE_ARRAY_WRITE(volume_stack, i, shader) = shader; },
+      [=](int i, int object) { INTEGRATOR_STATE_ARRAY_WRITE(volume_stack, i, object) = object; });
+}
 
-    /* Add to the end of the stack. */
-    INTEGRATOR_STATE_ARRAY_WRITE(shadow_volume_stack, i, shader) = sd->shader;
-    INTEGRATOR_STATE_ARRAY_WRITE(shadow_volume_stack, i, object) = sd->object;
-    INTEGRATOR_STATE_ARRAY_WRITE(shadow_volume_stack, i + 1, shader) = SHADER_NONE;
-  }
+ccl_device void shadow_volume_stack_enter_exit(INTEGRATOR_STATE_ARGS, const ShaderData *sd)
+{
+  volume_stack_enter_exit_common(
+      INTEGRATOR_STATE_PASS,
+      sd,
+      [=](int i) -> int { return INTEGRATOR_STATE_ARRAY(shadow_volume_stack, i, shader); },
+      [=](int i) -> int { return INTEGRATOR_STATE_ARRAY(shadow_volume_stack, i, object); },
+      [=](int i, int shader) {
+        INTEGRATOR_STATE_ARRAY_WRITE(shadow_volume_stack, i, shader) = shader;
+      },
+      [=](int i, int object) {
+        INTEGRATOR_STATE_ARRAY_WRITE(shadow_volume_stack, i, object) = object;
+      });
 }
 
 /* Clean stack after the last bounce.