ac/nir: Determine if input attachments are used in the info pass.

Reviewed-by: Dave Airlie <airlied@redhat.com>
diff --git a/src/amd/common/ac_shader_info.c b/src/amd/common/ac_shader_info.c
index 8668c4c..ca59965 100644
--- a/src/amd/common/ac_shader_info.c
+++ b/src/amd/common/ac_shader_info.c
@@ -64,9 +64,18 @@
 	case nir_intrinsic_image_atomic_xor:
 	case nir_intrinsic_image_atomic_exchange:
 	case nir_intrinsic_image_atomic_comp_swap:
-	case nir_intrinsic_image_size:
+	case nir_intrinsic_image_size: {
+		const struct glsl_type *type = instr->variables[0]->var->type;
+		if(instr->variables[0]->deref.child)
+			type = instr->variables[0]->deref.child->type;
+
+		enum glsl_sampler_dim dim = glsl_get_sampler_dim(type);
+		if (dim == GLSL_SAMPLER_DIM_SUBPASS ||
+		    dim == GLSL_SAMPLER_DIM_SUBPASS_MS)
+			info->ps.uses_input_attachments = true;
 		mark_sampler_desc(instr->variables[0]->var, info);
 		break;
+	}
 	default:
 		break;
 	}
diff --git a/src/amd/common/ac_shader_info.h b/src/amd/common/ac_shader_info.h
index 965ad54..886b5e8 100644
--- a/src/amd/common/ac_shader_info.h
+++ b/src/amd/common/ac_shader_info.h
@@ -38,6 +38,7 @@
 	struct {
 		bool force_persample;
 		bool needs_sample_positions;
+		bool uses_input_attachments;
 	} ps;
 	struct {
 		uint8_t grid_components_used;