diff --git a/src/intel/isl/isl.c b/src/intel/isl/isl.c
index e1745976f7e..60aa91ab0ed 100644
--- a/src/intel/isl/isl.c
+++ b/src/intel/isl/isl.c
@@ -3884,7 +3884,7 @@ isl_surf_get_ccs_surf(const struct isl_device *dev,
       isl_gfx30_##func(__VA_ARGS__);               \
       break;                                       \
    default:                                        \
-      assert(!"Unknown hardware generation");      \
+      unreachable("Unknown hardware generation");  \
    }
 
 /**
diff --git a/src/intel/isl/isl_format.c b/src/intel/isl/isl_format.c
index 1bb595be22d..e842ac63aa5 100644
--- a/src/intel/isl/isl_format.c
+++ b/src/intel/isl/isl_format.c
@@ -1087,8 +1087,7 @@ isl_format_has_color_component(enum isl_format fmt, int component)
    case 3:
       return (fmtl->channels.a.bits + intensity) > 0;
    default:
-      assert(!"Invalid color component: must be 0..3");
-      return false;
+      unreachable("Invalid color component: must be 0..3");
    }
 }
 
@@ -1212,8 +1211,7 @@ isl_format_rgbx_to_rgba(enum isl_format rgbx)
    case ISL_FORMAT_B5G5R5X1_UNORM_SRGB:
       return ISL_FORMAT_B5G5R5A1_UNORM_SRGB;
    default:
-      assert(!"Invalid RGBX format");
-      return rgbx;
+      unreachable("Invalid RGBX format");
    }
 }
 
diff --git a/src/intel/isl/isl_priv.h b/src/intel/isl/isl_priv.h
index 16e977bbf55..332900b17f8 100644
--- a/src/intel/isl/isl_priv.h
+++ b/src/intel/isl/isl_priv.h
@@ -82,8 +82,7 @@ typedef void (*isl_emit_cpb_control_s_func)(const struct isl_device *dev, void *
       case 300:                                                         \
          return isl_gfx30_##func;                                       \
       default:                                                          \
-         assert(!"Unknown hardware generation");                        \
-         return NULL;                                                   \
+         unreachable("Unknown hardware generation");                    \
       }                                                                 \
    }
 
diff --git a/src/intel/isl/isl_storage_image.c b/src/intel/isl/isl_storage_image.c
index 50b39d959b3..492e901cf7b 100644
--- a/src/intel/isl/isl_storage_image.c
+++ b/src/intel/isl/isl_storage_image.c
@@ -228,8 +228,7 @@ isl_lower_storage_image_format(const struct intel_device_info *devinfo,
       return ISL_FORMAT_R32G32_UINT;
 
    default:
-      assert(!"Unknown image format");
-      return ISL_FORMAT_UNSUPPORTED;
+      unreachable("Unknown image format");
    }
 }
 
@@ -338,7 +337,7 @@ isl_surf_fill_image_param(const struct isl_device *dev,
       break;
 
    default:
-      assert(!"Unhandled storage image tiling");
+      unreachable("Unhandled storage image tiling");
    }
 
    /* 3D textures are arranged in 2D in memory with 2^lod slices per row.  The
diff --git a/src/intel/isl/isl_surface_state.c b/src/intel/isl/isl_surface_state.c
index 68fbaa8479b..de9318758f7 100644
--- a/src/intel/isl/isl_surface_state.c
+++ b/src/intel/isl/isl_surface_state.c
@@ -747,8 +747,7 @@ isl_genX(surf_fill_state_s)(const struct isl_device *dev, void *state,
          case ISL_FORMAT_R16_UNORM:
             break;
          default:
-            assert(!"Incompatible HiZ Sampling format");
-            break;
+            unreachable("Incompatible HiZ Sampling format");
          }
       }