[Mesa-dev] [PATCH 15/15] radeonsi/nir: port some bindless and sampler code from TGSI

[Marek Olšák]

From: Marek Olšák <marek.olsak at amd.com>

These might be all missing changes for bindless textures.
---
 src/gallium/drivers/radeonsi/si_shader_nir.c | 80 ++++++++++++--------
 1 file changed, 50 insertions(+), 30 deletions(-)

diff --git a/src/gallium/drivers/radeonsi/si_shader_nir.c b/src/gallium/drivers/radeonsi/si_shader_nir.c
index 5d6280b80f7..87ca0161b45 100644
--- a/src/gallium/drivers/radeonsi/si_shader_nir.c
+++ b/src/gallium/drivers/radeonsi/si_shader_nir.c
@@ -890,64 +890,84 @@ si_nir_lookup_interp_param(struct ac_shader_abi *abi,
 }
 
 static LLVMValueRef
 si_nir_load_sampler_desc(struct ac_shader_abi *abi,
 		         unsigned descriptor_set, unsigned base_index,
 		         unsigned constant_index, LLVMValueRef dynamic_index,
 		         enum ac_descriptor_type desc_type, bool image,
 			 bool write, bool bindless)
 {
 	struct si_shader_context *ctx = si_shader_context_from_abi(abi);
+	const struct tgsi_shader_info *info = &ctx->shader->selector->info;
 	LLVMBuilderRef builder = ctx->ac.builder;
-	LLVMValueRef list = LLVMGetParam(ctx->main_fn, ctx->param_samplers_and_images);
-	LLVMValueRef index;
+	unsigned const_index = base_index + constant_index;
+	bool dcc_off = write;
+
+	/* TODO: images_store and images_atomic are not set */
+	if (!dynamic_index && image &&
+	    (info->images_store | info->images_atomic) & (1 << const_index))
+		dcc_off = true;
 
 	assert(!descriptor_set);
+	assert(!image || desc_type == AC_DESC_IMAGE || desc_type == AC_DESC_BUFFER);
 
-	dynamic_index = dynamic_index ? dynamic_index : ctx->ac.i32_0;
-	index = LLVMBuildAdd(builder, dynamic_index,
-			     LLVMConstInt(ctx->ac.i32, base_index + constant_index, false),
-			     "");
+	if (bindless) {
+		LLVMValueRef list =
+			LLVMGetParam(ctx->main_fn, ctx->param_bindless_samplers_and_images);
 
-	if (image) {
-		assert(desc_type == AC_DESC_IMAGE || desc_type == AC_DESC_BUFFER);
-		assert(base_index + constant_index < ctx->num_images);
+		/* dynamic_index is the bindless handle */
+		if (image) {
+			return si_load_image_desc(ctx, list, dynamic_index, desc_type,
+						  dcc_off, true);
+		}
+
+		/* Since bindless handle arithmetic can contain an unsigned integer
+		 * wraparound and si_load_sampler_desc assumes there isn't any,
+		 * use GEP without "inbounds" (inside ac_build_pointer_add)
+		 * to prevent incorrect code generation and hangs.
+		 */
+		dynamic_index = LLVMBuildMul(ctx->ac.builder, dynamic_index,
+					     LLVMConstInt(ctx->i32, 2, 0), "");
+		list = ac_build_pointer_add(&ctx->ac, list, dynamic_index);
+		return si_load_sampler_desc(ctx, list, ctx->i32_0, desc_type);
+	}
+
+	unsigned num_slots = image ? ctx->num_images : ctx->num_samplers;
+	assert(const_index < num_slots);
 
-		if (dynamic_index)
-			index = si_llvm_bound_index(ctx, index, ctx->num_images);
+	LLVMValueRef list = LLVMGetParam(ctx->main_fn, ctx->param_samplers_and_images);
+	LLVMValueRef index = LLVMConstInt(ctx->ac.i32, const_index, false);
+
+	if (dynamic_index) {
+		index = LLVMBuildAdd(builder, index, dynamic_index, "");
+
+		/* From the GL_ARB_shader_image_load_store extension spec:
+		 *
+		 *    If a shader performs an image load, store, or atomic
+		 *    operation using an image variable declared as an array,
+		 *    and if the index used to select an individual element is
+		 *    negative or greater than or equal to the size of the
+		 *    array, the results of the operation are undefined but may
+		 *    not lead to termination.
+		 */
+		index = si_llvm_bound_index(ctx, index, num_slots);
+	}
 
+	if (image) {
 		index = LLVMBuildSub(ctx->ac.builder,
 				     LLVMConstInt(ctx->i32, SI_NUM_IMAGES - 1, 0),
 				     index, "");
-
-		/* TODO: be smarter about when we use dcc_off */
-		return si_load_image_desc(ctx, list, index, desc_type, write, bindless);
+		return si_load_image_desc(ctx, list, index, desc_type, dcc_off, false);
 	}
 
-	assert(base_index + constant_index < ctx->num_samplers);
-
-	if (dynamic_index)
-		index = si_llvm_bound_index(ctx, index, ctx->num_samplers);
-
 	index = LLVMBuildAdd(ctx->ac.builder, index,
 			     LLVMConstInt(ctx->i32, SI_NUM_IMAGES / 2, 0), "");
-
-	if (bindless) {
-		/* Since bindless handle arithmetic can contain an unsigned integer
-		 * wraparound and si_load_sampler_desc assumes there isn't any,
-		 * use GEP without "inbounds" (inside ac_build_pointer_add)
-		 * to prevent incorrect code generation and hangs.
-		 */
-		index = LLVMBuildMul(ctx->ac.builder, index, LLVMConstInt(ctx->i32, 2, 0), "");
-		list = ac_build_pointer_add(&ctx->ac, list, index);
-		index = ctx->i32_0;
-	}
 	return si_load_sampler_desc(ctx, list, index, desc_type);
 }
 
 static void bitcast_inputs(struct si_shader_context *ctx,
 			   LLVMValueRef data[4],
 			   unsigned input_idx)
 {
 	for (unsigned chan = 0; chan < 4; chan++) {
 		ctx->inputs[input_idx + chan] =
 			LLVMBuildBitCast(ctx->ac.builder, data[chan], ctx->ac.i32, "");
-- 
2.17.1