radeonsi: put image, fmask, and sampler descriptors into one array

The texture slot is expanded to 16 dwords containing 2 descriptors.
Those can be:
- Image and fmask, or
- Image and sampler state

By carefully choosing the locations, we can put all three into one slot,
with the fmask and sampler state being mutually exclusive.

This improves shaders in 2 ways:
- 2 user SGPRs are unused, shaders can use them as temporary registers now
- each pair of descriptors is always on the same cache line

v2: cosmetic changes: add back v8i32, don't load a sampler state & fmask
    at the same time

Reviewed-by: Nicolai Hähnle <nicolai.haehnle@amd.com>

6 files changed, 138 insertions, 116 deletions

diff --git a/src/gallium/drivers/radeonsi/si_blit.c b/src/gallium/drivers/radeonsi/si_blit.c
index a93887e..1158770 100644
--- a/src/gallium/drivers/radeonsi/si_blit.c
+++ b/src/gallium/drivers/radeonsi/si_blit.c
@@ -80,7 +80,7 @@ static void si_blitter_begin(struct pipe_context *ctx, enum si_blitter_op op)
 	if (op & SI_SAVE_TEXTURES) {
 		util_blitter_save_fragment_sampler_states(
 			sctx->blitter, 2,
-			sctx->samplers[PIPE_SHADER_FRAGMENT].states.saved_states);
+			sctx->samplers[PIPE_SHADER_FRAGMENT].views.sampler_states);
 
 		util_blitter_save_fragment_sampler_views(sctx->blitter, 2,
 			sctx->samplers[PIPE_SHADER_FRAGMENT].views.views);
diff --git a/src/gallium/drivers/radeonsi/si_descriptors.c b/src/gallium/drivers/radeonsi/si_descriptors.c
index 6c79673..34cc06f 100644
--- a/src/gallium/drivers/radeonsi/si_descriptors.c
+++ b/src/gallium/drivers/radeonsi/si_descriptors.c
@@ -41,6 +41,18 @@
  *
  * Also, uploading descriptors to newly allocated memory doesn't require
  * a KCACHE flush.
+ *
+ *
+ * Possible scenarios for one 16 dword image+sampler slot:
+ *
+ *       | Image        | w/ FMASK   | Buffer       | NULL
+ * [ 0: 3] Image[0:3]   | Image[0:3] | Null[0:3]    | Null[0:3]
+ * [ 4: 7] Image[4:7]   | Image[4:7] | Buffer[0:3]  | 0
+ * [ 8:11] Null[0:3]    | Fmask[0:3] | Null[0:3]    | Null[0:3]
+ * [12:15] Sampler[0:3] | Fmask[4:7] | Sampler[0:3] | Sampler[0:3]
+ *
+ * FMASK implies MSAA, therefore no sampler state.
+ * Sampler states are never unbound except when FMASK is bound.
  */
 
 #include "radeon/r600_cs.h"
@@ -88,9 +100,9 @@ static void si_init_descriptors(struct si_descriptors *desc,
 	desc->shader_userdata_offset = shader_userdata_index * 4;
 
 	/* Initialize the array to NULL descriptors if the element size is 8. */
-	if (element_dw_size == 8)
-		for (i = 0; i < num_elements; i++)
-			memcpy(desc->list + i*element_dw_size, null_descriptor,
+	if (element_dw_size % 8 == 0)
+		for (i = 0; i < num_elements * element_dw_size / 8; i++)
+			memcpy(desc->list + i*8, null_descriptor,
 			       sizeof(null_descriptor));
 }
 
@@ -174,27 +186,42 @@ static void si_sampler_views_begin_new_cs(struct si_context *sctx,
 			      RADEON_USAGE_READWRITE, RADEON_PRIO_DESCRIPTORS);
 }
 
-static void si_set_sampler_view(struct si_context *sctx, unsigned shader,
-				unsigned slot, struct pipe_sampler_view *view,
-				unsigned *view_desc)
+static void si_set_sampler_view(struct si_context *sctx,
+				struct si_sampler_views *views,
+				unsigned slot, struct pipe_sampler_view *view)
 {
-	struct si_sampler_views *views = &sctx->samplers[shader].views;
-
 	if (views->views[slot] == view)
 		return;
 
 	if (view) {
 		struct si_sampler_view *rview =
 			(struct si_sampler_view*)view;
+		struct r600_texture *rtex = (struct r600_texture*)view->texture;
 
 		si_sampler_view_add_buffers(sctx, rview);
 
 		pipe_sampler_view_reference(&views->views[slot], view);
-		memcpy(views->desc.list + slot*8, view_desc, 8*4);
+		memcpy(views->desc.list + slot * 16, rview->state, 8*4);
+
+		if (rtex && rtex->fmask.size) {
+			memcpy(views->desc.list + slot*16 + 8,
+			       rview->fmask_state, 8*4);
+		} else {
+			/* Disable FMASK and bind sampler state in [12:15]. */
+			memcpy(views->desc.list + slot*16 + 8,
+			       null_descriptor, 4*4);
+
+			if (views->sampler_states[slot])
+				memcpy(views->desc.list + slot*16 + 12,
+				       views->sampler_states[slot], 4*4);
+		}
+
 		views->desc.enabled_mask |= 1llu << slot;
 	} else {
 		pipe_sampler_view_reference(&views->views[slot], NULL);
-		memcpy(views->desc.list + slot*8, null_descriptor, 8*4);
+		memcpy(views->desc.list + slot*16, null_descriptor, 8*4);
+		/* Only clear the lower dwords of FMASK. */
+		memcpy(views->desc.list + slot*16 + 8, null_descriptor, 4*4);
 		views->desc.enabled_mask &= ~(1llu << slot);
 	}
 
@@ -208,7 +235,6 @@ static void si_set_sampler_views(struct pipe_context *ctx,
 {
 	struct si_context *sctx = (struct si_context *)ctx;
 	struct si_textures_info *samplers = &sctx->samplers[shader];
-	struct si_sampler_view **rviews = (struct si_sampler_view **)views;
 	int i;
 
 	if (!count || shader >= SI_NUM_SHADERS)
@@ -220,13 +246,11 @@ static void si_set_sampler_views(struct pipe_context *ctx,
 		if (!views || !views[i]) {
 			samplers->depth_texture_mask &= ~(1 << slot);
 			samplers->compressed_colortex_mask &= ~(1 << slot);
-			si_set_sampler_view(sctx, shader, slot, NULL, NULL);
-			si_set_sampler_view(sctx, shader, SI_FMASK_TEX_OFFSET + slot,
-					    NULL, NULL);
+			si_set_sampler_view(sctx, &samplers->views, slot, NULL);
 			continue;
 		}
 
-		si_set_sampler_view(sctx, shader, slot, views[i], rviews[i]->state);
+		si_set_sampler_view(sctx, &samplers->views, slot, views[i]);
 
 		if (views[i]->texture && views[i]->texture->target != PIPE_BUFFER) {
 			struct r600_texture *rtex =
@@ -243,60 +267,46 @@ static void si_set_sampler_views(struct pipe_context *ctx,
 			} else {
 				samplers->compressed_colortex_mask &= ~(1 << slot);
 			}
-
-			if (rtex->fmask.size) {
-				si_set_sampler_view(sctx, shader, SI_FMASK_TEX_OFFSET + slot,
-						    views[i], rviews[i]->fmask_state);
-			} else {
-				si_set_sampler_view(sctx, shader, SI_FMASK_TEX_OFFSET + slot,
-						    NULL, NULL);
-			}
 		} else {
 			samplers->depth_texture_mask &= ~(1 << slot);
 			samplers->compressed_colortex_mask &= ~(1 << slot);
-			si_set_sampler_view(sctx, shader, SI_FMASK_TEX_OFFSET + slot,
-					    NULL, NULL);
 		}
 	}
 }
 
 /* SAMPLER STATES */
 
-static void si_sampler_states_begin_new_cs(struct si_context *sctx,
-					   struct si_sampler_states *states)
-{
-	if (!states->desc.buffer)
-		return;
-	radeon_add_to_buffer_list(&sctx->b, &sctx->b.gfx, states->desc.buffer,
-			      RADEON_USAGE_READWRITE, RADEON_PRIO_DESCRIPTORS);
-}
-
 static void si_bind_sampler_states(struct pipe_context *ctx, unsigned shader,
                                    unsigned start, unsigned count, void **states)
 {
 	struct si_context *sctx = (struct si_context *)ctx;
-	struct si_sampler_states *samplers = &sctx->samplers[shader].states;
+	struct si_textures_info *samplers = &sctx->samplers[shader];
+	struct si_descriptors *desc = &samplers->views.desc;
 	struct si_sampler_state **sstates = (struct si_sampler_state**)states;
 	int i;
 
 	if (!count || shader >= SI_NUM_SHADERS)
 		return;
 
-	if (start == 0)
-		samplers->saved_states[0] = states[0];
-	if (start == 1)
-		samplers->saved_states[1] = states[0];
-	else if (start == 0 && count >= 2)
-		samplers->saved_states[1] = states[1];
-
 	for (i = 0; i < count; i++) {
 		unsigned slot = start + i;
 
-		if (!sstates[i])
+		if (!sstates[i] ||
+		    sstates[i] == samplers->views.sampler_states[slot])
+			continue;
+
+		samplers->views.sampler_states[slot] = sstates[i];
+
+		/* If FMASK is bound, don't overwrite it.
+		 * The sampler state will be set after FMASK is unbound.
+		 */
+		if (samplers->views.views[i] &&
+		    samplers->views.views[i]->texture &&
+		    ((struct r600_texture*)samplers->views.views[i]->texture)->fmask.size)
 			continue;
 
-		memcpy(samplers->desc.list + slot*4, sstates[i]->val, 4*4);
-		samplers->desc.list_dirty = true;
+		memcpy(desc->list + slot * 16 + 12, sstates[i]->val, 4*4);
+		desc->list_dirty = true;
 	}
 }
 
@@ -862,7 +872,9 @@ static void si_invalidate_buffer(struct pipe_context *ctx, struct pipe_resource
 		while (mask) {
 			unsigned i = u_bit_scan64(&mask);
 			if (views->views[i]->texture == buf) {
-				si_desc_reset_buffer_offset(ctx, views->desc.list + i*8+4,
+				si_desc_reset_buffer_offset(ctx,
+							    views->desc.list +
+							    i * 16 + 4,
 							    old_va, buf);
 				views->desc.list_dirty = true;
 
@@ -882,7 +894,6 @@ static void si_mark_shader_pointers_dirty(struct si_context *sctx,
 	sctx->const_buffers[shader].desc.pointer_dirty = true;
 	sctx->rw_buffers[shader].desc.pointer_dirty = true;
 	sctx->samplers[shader].views.desc.pointer_dirty = true;
-	sctx->samplers[shader].states.desc.pointer_dirty = true;
 
 	if (shader == PIPE_SHADER_VERTEX)
 		sctx->vertex_buffers.pointer_dirty = true;
@@ -1003,7 +1014,6 @@ void si_emit_shader_userdata(struct si_context *sctx, struct r600_atom *atom)
 
 		si_emit_shader_pointer(sctx, &sctx->const_buffers[i].desc, base, false);
 		si_emit_shader_pointer(sctx, &sctx->samplers[i].views.desc, base, false);
-		si_emit_shader_pointer(sctx, &sctx->samplers[i].states.desc, base, false);
 	}
 	si_emit_shader_pointer(sctx, &sctx->vertex_buffers, sh_base[PIPE_SHADER_VERTEX], false);
 }
@@ -1023,9 +1033,7 @@ void si_init_all_descriptors(struct si_context *sctx)
 					 RADEON_USAGE_READWRITE, RADEON_PRIO_RINGS_STREAMOUT);
 
 		si_init_descriptors(&sctx->samplers[i].views.desc,
-				    SI_SGPR_SAMPLER_VIEWS, 8, SI_NUM_SAMPLER_VIEWS);
-		si_init_descriptors(&sctx->samplers[i].states.desc,
-				    SI_SGPR_SAMPLER_STATES, 4, SI_NUM_SAMPLER_STATES);
+				    SI_SGPR_SAMPLERS, 16, SI_NUM_SAMPLERS);
 	}
 
 	si_init_descriptors(&sctx->vertex_buffers, SI_SGPR_VERTEX_BUFFERS,
@@ -1056,8 +1064,7 @@ bool si_upload_shader_descriptors(struct si_context *sctx)
 	for (i = 0; i < SI_NUM_SHADERS; i++) {
 		if (!si_upload_descriptors(sctx, &sctx->const_buffers[i].desc) ||
 		    !si_upload_descriptors(sctx, &sctx->rw_buffers[i].desc) ||
-		    !si_upload_descriptors(sctx, &sctx->samplers[i].views.desc) ||
-		    !si_upload_descriptors(sctx, &sctx->samplers[i].states.desc))
+		    !si_upload_descriptors(sctx, &sctx->samplers[i].views.desc))
 			return false;
 	}
 	return si_upload_vertex_buffer_descriptors(sctx);
@@ -1071,7 +1078,6 @@ void si_release_all_descriptors(struct si_context *sctx)
 		si_release_buffer_resources(&sctx->const_buffers[i]);
 		si_release_buffer_resources(&sctx->rw_buffers[i]);
 		si_release_sampler_views(&sctx->samplers[i].views);
-		si_release_descriptors(&sctx->samplers[i].states.desc);
 	}
 	si_release_descriptors(&sctx->vertex_buffers);
 }
@@ -1084,7 +1090,6 @@ void si_all_descriptors_begin_new_cs(struct si_context *sctx)
 		si_buffer_resources_begin_new_cs(sctx, &sctx->const_buffers[i]);
 		si_buffer_resources_begin_new_cs(sctx, &sctx->rw_buffers[i]);
 		si_sampler_views_begin_new_cs(sctx, &sctx->samplers[i].views);
-		si_sampler_states_begin_new_cs(sctx, &sctx->samplers[i].states);
 	}
 	si_vertex_buffers_begin_new_cs(sctx);
 	si_shader_userdata_begin_new_cs(sctx);
diff --git a/src/gallium/drivers/radeonsi/si_pipe.h b/src/gallium/drivers/radeonsi/si_pipe.h
index 3c963db..b5790d6 100644
--- a/src/gallium/drivers/radeonsi/si_pipe.h
+++ b/src/gallium/drivers/radeonsi/si_pipe.h
@@ -113,7 +113,6 @@ struct si_cs_shader_state {
 
 struct si_textures_info {
 	struct si_sampler_views		views;
-	struct si_sampler_states	states;
 	uint32_t			depth_texture_mask; /* which textures are depth */
 	uint32_t			compressed_colortex_mask;
 };
diff --git a/src/gallium/drivers/radeonsi/si_shader.c b/src/gallium/drivers/radeonsi/si_shader.c
index c1d3edc..db922f0 100644
--- a/src/gallium/drivers/radeonsi/si_shader.c
+++ b/src/gallium/drivers/radeonsi/si_shader.c
@@ -86,8 +86,9 @@ struct si_shader_context
 	LLVMValueRef const_buffers[SI_NUM_CONST_BUFFERS];
 	LLVMValueRef lds;
 	LLVMValueRef *constants[SI_NUM_CONST_BUFFERS];
-	LLVMValueRef sampler_views[SI_NUM_SAMPLER_VIEWS];
-	LLVMValueRef sampler_states[SI_NUM_SAMPLER_STATES];
+	LLVMValueRef sampler_views[SI_NUM_SAMPLERS];
+	LLVMValueRef sampler_states[SI_NUM_SAMPLERS];
+	LLVMValueRef fmasks[SI_NUM_USER_SAMPLERS];
 	LLVMValueRef so_buffers[4];
 	LLVMValueRef esgs_ring;
 	LLVMValueRef gsvs_ring[4];
@@ -2480,13 +2481,58 @@ static void set_tex_fetch_args(struct gallivm_state *gallivm,
 
 static const struct lp_build_tgsi_action tex_action;
 
+enum desc_type {
+	DESC_IMAGE,
+	DESC_FMASK,
+	DESC_SAMPLER
+};
+
+static LLVMTypeRef const_array(LLVMTypeRef elem_type, int num_elements)
+{
+	return LLVMPointerType(LLVMArrayType(elem_type, num_elements),
+			       CONST_ADDR_SPACE);
+}
+
+/**
+ * Load an image view, fmask view. or sampler state descriptor.
+ */
+static LLVMValueRef get_sampler_desc(struct si_shader_context *si_shader_ctx,
+				     LLVMValueRef index, enum desc_type type)
+{
+	struct gallivm_state *gallivm = &si_shader_ctx->radeon_bld.gallivm;
+	LLVMTypeRef i32 = LLVMInt32TypeInContext(gallivm->context);
+	LLVMBuilderRef builder = gallivm->builder;
+	LLVMValueRef ptr = LLVMGetParam(si_shader_ctx->radeon_bld.main_fn,
+					SI_PARAM_SAMPLERS);
+
+	switch (type) {
+	case DESC_IMAGE:
+		/* The image is at [0:7]. */
+		index = LLVMBuildMul(builder, index, LLVMConstInt(i32, 2, 0), "");
+		break;
+	case DESC_FMASK:
+		/* The FMASK is at [8:15]. */
+		index = LLVMBuildMul(builder, index, LLVMConstInt(i32, 2, 0), "");
+		index = LLVMBuildAdd(builder, index, LLVMConstInt(i32, 1, 0), "");
+		break;
+	case DESC_SAMPLER:
+		/* The sampler state is at [12:15]. */
+		index = LLVMBuildMul(builder, index, LLVMConstInt(i32, 4, 0), "");
+		index = LLVMBuildAdd(builder, index, LLVMConstInt(i32, 3, 0), "");
+		ptr = LLVMBuildPointerCast(builder, ptr,
+					   const_array(LLVMVectorType(i32, 4), 0), "");
+		break;
+	}
+
+	return build_indexed_load_const(si_shader_ctx, ptr, index);
+}
+
 static void tex_fetch_ptrs(
 	struct lp_build_tgsi_context * bld_base,
 	struct lp_build_emit_data * emit_data,
 	LLVMValueRef *res_ptr, LLVMValueRef *samp_ptr, LLVMValueRef *fmask_ptr)
 {
 	struct si_shader_context *si_shader_ctx = si_shader_context(bld_base);
-	struct gallivm_state *gallivm = bld_base->base.gallivm;
 	const struct tgsi_full_instruction * inst = emit_data->inst;
 	unsigned target = inst->Texture.Texture;
 	unsigned sampler_src;
@@ -2501,24 +2547,20 @@ static void tex_fetch_ptrs(
 
 		ind_index = get_indirect_index(si_shader_ctx, &reg->Indirect, reg->Register.Index);
 
-		*res_ptr = LLVMGetParam(si_shader_ctx->radeon_bld.main_fn, SI_PARAM_SAMPLER_VIEWS);
-		*res_ptr = build_indexed_load_const(si_shader_ctx, *res_ptr, ind_index);
-
-		*samp_ptr = LLVMGetParam(si_shader_ctx->radeon_bld.main_fn, SI_PARAM_SAMPLER_STATES);
-		*samp_ptr = build_indexed_load_const(si_shader_ctx, *samp_ptr, ind_index);
+		*res_ptr = get_sampler_desc(si_shader_ctx, ind_index, DESC_IMAGE);
 
 		if (target == TGSI_TEXTURE_2D_MSAA ||
 		    target == TGSI_TEXTURE_2D_ARRAY_MSAA) {
-			ind_index = LLVMBuildAdd(gallivm->builder, ind_index,
-						 lp_build_const_int32(gallivm,
-								      SI_FMASK_TEX_OFFSET), "");
-			*fmask_ptr = LLVMGetParam(si_shader_ctx->radeon_bld.main_fn, SI_PARAM_SAMPLER_VIEWS);
-			*fmask_ptr = build_indexed_load_const(si_shader_ctx, *fmask_ptr, ind_index);
+			*samp_ptr = NULL;
+			*fmask_ptr = get_sampler_desc(si_shader_ctx, ind_index, DESC_FMASK);
+		} else {
+			*samp_ptr = get_sampler_desc(si_shader_ctx, ind_index, DESC_SAMPLER);
+			*fmask_ptr = NULL;
 		}
 	} else {
 		*res_ptr = si_shader_ctx->sampler_views[sampler_index];
 		*samp_ptr = si_shader_ctx->sampler_states[sampler_index];
-		*fmask_ptr = si_shader_ctx->sampler_views[SI_FMASK_TEX_OFFSET + sampler_index];
+		*fmask_ptr = si_shader_ctx->fmasks[sampler_index];
 	}
 }
 
@@ -3498,12 +3540,6 @@ static void create_meta_data(struct si_shader_context *si_shader_ctx)
 	si_shader_ctx->const_md = LLVMMDNodeInContext(gallivm->context, args, 3);
 }
 
-static LLVMTypeRef const_array(LLVMTypeRef elem_type, int num_elements)
-{
-	return LLVMPointerType(LLVMArrayType(elem_type, num_elements),
-			       CONST_ADDR_SPACE);
-}
-
 static void declare_streamout_params(struct si_shader_context *si_shader_ctx,
 				     struct pipe_stream_output_info *so,
 				     LLVMTypeRef *params, LLVMTypeRef i32,
@@ -3530,7 +3566,7 @@ static void create_function(struct si_shader_context *si_shader_ctx)
 	struct lp_build_tgsi_context *bld_base = &si_shader_ctx->radeon_bld.soa.bld_base;
 	struct gallivm_state *gallivm = bld_base->base.gallivm;
 	struct si_shader *shader = si_shader_ctx->shader;
-	LLVMTypeRef params[SI_NUM_PARAMS], f32, i8, i32, v2i32, v3i32, v16i8, v4i32, v8i32;
+	LLVMTypeRef params[SI_NUM_PARAMS], f32, i8, i32, v2i32, v3i32, v16i8, v8i32;
 	unsigned i, last_array_pointer, last_sgpr, num_params;
 
 	i8 = LLVMInt8TypeInContext(gallivm->context);
@@ -3538,15 +3574,14 @@ static void create_function(struct si_shader_context *si_shader_ctx)
 	f32 = LLVMFloatTypeInContext(gallivm->context);
 	v2i32 = LLVMVectorType(i32, 2);
 	v3i32 = LLVMVectorType(i32, 3);
-	v4i32 = LLVMVectorType(i32, 4);
 	v8i32 = LLVMVectorType(i32, 8);
 	v16i8 = LLVMVectorType(i8, 16);
 
 	params[SI_PARAM_RW_BUFFERS] = const_array(v16i8, SI_NUM_RW_BUFFERS);
 	params[SI_PARAM_CONST_BUFFERS] = const_array(v16i8, SI_NUM_CONST_BUFFERS);
-	params[SI_PARAM_SAMPLER_STATES] = const_array(v4i32, SI_NUM_SAMPLER_STATES);
-	params[SI_PARAM_SAMPLER_VIEWS] = const_array(v8i32, SI_NUM_SAMPLER_VIEWS);
-	last_array_pointer = SI_PARAM_SAMPLER_VIEWS;
+	params[SI_PARAM_SAMPLERS] = const_array(v8i32, SI_NUM_SAMPLERS);
+	params[SI_PARAM_UNUSED] = LLVMPointerType(i32, CONST_ADDR_SPACE);
+	last_array_pointer = SI_PARAM_UNUSED;
 
 	switch (si_shader_ctx->type) {
 	case TGSI_PROCESSOR_VERTEX:
@@ -3747,34 +3782,26 @@ static void preload_samplers(struct si_shader_context *si_shader_ctx)
 	struct lp_build_tgsi_context * bld_base = &si_shader_ctx->radeon_bld.soa.bld_base;
 	struct gallivm_state * gallivm = bld_base->base.gallivm;
 	const struct tgsi_shader_info * info = bld_base->info;
-
 	unsigned i, num_samplers = info->file_max[TGSI_FILE_SAMPLER] + 1;
-
-	LLVMValueRef res_ptr, samp_ptr;
 	LLVMValueRef offset;
 
 	if (num_samplers == 0)
 		return;
 
-	res_ptr = LLVMGetParam(si_shader_ctx->radeon_bld.main_fn, SI_PARAM_SAMPLER_VIEWS);
-	samp_ptr = LLVMGetParam(si_shader_ctx->radeon_bld.main_fn, SI_PARAM_SAMPLER_STATES);
-
 	/* Load the resources and samplers, we rely on the code sinking to do the rest */
 	for (i = 0; i < num_samplers; ++i) {
 		/* Resource */
 		offset = lp_build_const_int32(gallivm, i);
-		si_shader_ctx->sampler_views[i] = build_indexed_load_const(si_shader_ctx, res_ptr, offset);
-
-		/* Sampler */
-		offset = lp_build_const_int32(gallivm, i);
-		si_shader_ctx->sampler_states[i] = build_indexed_load_const(si_shader_ctx, samp_ptr, offset);
+		si_shader_ctx->sampler_views[i] =
+			get_sampler_desc(si_shader_ctx, offset, DESC_IMAGE);
 
 		/* FMASK resource */
-		if (info->is_msaa_sampler[i]) {
-			offset = lp_build_const_int32(gallivm, SI_FMASK_TEX_OFFSET + i);
-			si_shader_ctx->sampler_views[SI_FMASK_TEX_OFFSET + i] =
-				build_indexed_load_const(si_shader_ctx, res_ptr, offset);
-		}
+		if (info->is_msaa_sampler[i])
+			si_shader_ctx->fmasks[i] =
+				get_sampler_desc(si_shader_ctx, offset, DESC_FMASK);
+		else
+			si_shader_ctx->sampler_states[i] =
+				get_sampler_desc(si_shader_ctx, offset, DESC_SAMPLER);
 	}
 }
 
diff --git a/src/gallium/drivers/radeonsi/si_shader.h b/src/gallium/drivers/radeonsi/si_shader.h
index c42c51e..dc75e03 100644
--- a/src/gallium/drivers/radeonsi/si_shader.h
+++ b/src/gallium/drivers/radeonsi/si_shader.h
@@ -77,8 +77,8 @@ struct radeon_shader_reloc;
 
 #define SI_SGPR_RW_BUFFERS	0  /* rings (& stream-out, VS only) */
 #define SI_SGPR_CONST_BUFFERS	2
-#define SI_SGPR_SAMPLER_STATES	4
-#define SI_SGPR_SAMPLER_VIEWS	6
+#define SI_SGPR_SAMPLERS	4  /* images & sampler states interleaved */
+/* TODO: gap */
 #define SI_SGPR_VERTEX_BUFFERS	8  /* VS only */
 #define SI_SGPR_BASE_VERTEX	10 /* VS only */
 #define SI_SGPR_START_INSTANCE	11 /* VS only */
@@ -101,8 +101,8 @@ struct radeon_shader_reloc;
 /* LLVM function parameter indices */
 #define SI_PARAM_RW_BUFFERS	0
 #define SI_PARAM_CONST_BUFFERS	1
-#define SI_PARAM_SAMPLER_STATES	2
-#define SI_PARAM_SAMPLER_VIEWS	3
+#define SI_PARAM_SAMPLERS	2
+#define SI_PARAM_UNUSED		3 /* TODO: use */
 
 /* VS only parameters */
 #define SI_PARAM_VERTEX_BUFFERS	4
diff --git a/src/gallium/drivers/radeonsi/si_state.h b/src/gallium/drivers/radeonsi/si_state.h
index e9a0175..f64c4d4 100644
--- a/src/gallium/drivers/radeonsi/si_state.h
+++ b/src/gallium/drivers/radeonsi/si_state.h
@@ -144,17 +144,12 @@ struct si_shader_data {
 	uint32_t		sh_base[SI_NUM_SHADERS];
 };
 
-#define SI_NUM_USER_SAMPLERS            16 /* AKA OpenGL textures units per shader */
-#define SI_POLY_STIPPLE_SAMPLER         SI_NUM_USER_SAMPLERS
-#define SI_NUM_SAMPLERS                 (SI_POLY_STIPPLE_SAMPLER + 1)
-
 /* User sampler views:   0..15
  * Polygon stipple tex:  16
- * FMASK sampler views:  17..33 (no sampler states)
  */
-#define SI_FMASK_TEX_OFFSET		SI_NUM_SAMPLERS
-#define SI_NUM_SAMPLER_VIEWS		(SI_FMASK_TEX_OFFSET + SI_NUM_SAMPLERS)
-#define SI_NUM_SAMPLER_STATES		SI_NUM_SAMPLERS
+#define SI_NUM_USER_SAMPLERS            16 /* AKA OpenGL textures units per shader */
+#define SI_POLY_STIPPLE_SAMPLER         SI_NUM_USER_SAMPLERS
+#define SI_NUM_SAMPLERS                 (SI_POLY_STIPPLE_SAMPLER + 1)
 
 /* User constant buffers:   0..15
  * Driver state constants:  16
@@ -210,12 +205,8 @@ struct si_descriptors {
 
 struct si_sampler_views {
 	struct si_descriptors		desc;
-	struct pipe_sampler_view	*views[SI_NUM_SAMPLER_VIEWS];
-};
-
-struct si_sampler_states {
-	struct si_descriptors		desc;
-	void				*saved_states[2]; /* saved for u_blitter */
+	struct pipe_sampler_view	*views[SI_NUM_SAMPLERS];
+	void				*sampler_states[SI_NUM_SAMPLERS];
 };
 
 struct si_buffer_resources {