[Mesa-dev] [PATCH 2/2] radeonsi: Use buffer_load intrinsics instead of llvm.SI.vs.load.input

[Tom Stellard]

---
 src/gallium/drivers/radeonsi/si_shader.c | 69 +++++++++++++++++++++++---------
 1 file changed, 50 insertions(+), 19 deletions(-)

diff --git a/src/gallium/drivers/radeonsi/si_shader.c b/src/gallium/drivers/radeonsi/si_shader.c
index 306e12f..ee4fe2f 100644
--- a/src/gallium/drivers/radeonsi/si_shader.c
+++ b/src/gallium/drivers/radeonsi/si_shader.c
@@ -82,6 +82,17 @@ static void si_build_ps_prolog_function(struct si_shader_context *ctx,
 static void si_build_ps_epilog_function(struct si_shader_context *ctx,
 					union si_shader_part_key *key);
 
+static LLVMValueRef build_buffer_load(struct si_shader_context *ctx,
+                                      LLVMValueRef rsrc,
+                                      int num_channels,
+                                      LLVMValueRef vindex,
+                                      LLVMValueRef voffset,
+                                      LLVMValueRef soffset,
+                                      unsigned inst_offset,
+                                      unsigned glc,
+                                      unsigned slc,
+				      bool is_format);
+
 /* Ideally pass the sample mask input to the PS epilog as v13, which
  * is its usual location, so that the shader doesn't have to add v_mov.
  */
@@ -368,6 +379,31 @@ static LLVMValueRef get_instance_index_for_fetch(
 			    LLVMGetParam(radeon_bld->main_fn, param_start_instance), "");
 }
 
+static LLVMValueRef build_vs_load_input(struct si_shader_context *ctx,
+					LLVMValueRef rsrc,
+					LLVMValueRef index,
+					LLVMValueRef offset) {
+
+	struct lp_build_context *base = &ctx->soa.bld_base.base;
+	struct lp_build_context *uint =	&ctx->soa.bld_base.uint_bld;
+	struct gallivm_state *gallivm = base->gallivm;
+
+	LLVMValueRef args[8];
+
+	if (HAVE_LLVM < 0x0400) {
+		args[0] = rsrc;
+		args[1] = offset;
+		args[2] = index;
+
+		return lp_build_intrinsic(gallivm->builder,
+			"llvm.SI.vs.load.input", ctx->v4f32, args, 3,
+			LP_FUNC_ATTR_READNONE);
+	}
+
+	return build_buffer_load(ctx, rsrc, 4, index, offset,
+				 uint->zero, 0, 0, 0, true);
+}
+
 static void declare_input_vs(
 	struct si_shader_context *ctx,
 	unsigned input_index,
@@ -385,7 +421,6 @@ static void declare_input_vs(
 	LLVMValueRef t_list;
 	LLVMValueRef attribute_offset;
 	LLVMValueRef buffer_index;
-	LLVMValueRef args[3];
 	LLVMValueRef input;
 
 	/* Load the T list */
@@ -402,12 +437,8 @@ static void declare_input_vs(
 				    ctx->param_vertex_index0 +
 				    input_index);
 
-	args[0] = t_list;
-	args[1] = attribute_offset;
-	args[2] = buffer_index;
-	input = lp_build_intrinsic(gallivm->builder,
-		"llvm.SI.vs.load.input", ctx->v4f32, args, 3,
-		LP_FUNC_ATTR_READNONE);
+	input = build_vs_load_input(ctx, t_list, buffer_index,
+				    attribute_offset);
 
 	/* Break up the vec4 into individual components */
 	for (chan = 0; chan < 4; chan++) {
@@ -808,7 +839,8 @@ static LLVMValueRef build_buffer_load(struct si_shader_context *ctx,
                                       LLVMValueRef soffset,
                                       unsigned inst_offset,
                                       unsigned glc,
-                                      unsigned slc)
+                                      unsigned slc,
+				      bool is_format)
 {
 	struct gallivm_state *gallivm = &ctx->gallivm;
 	unsigned func = CLAMP(num_channels, 1, 3) - 1;
@@ -837,8 +869,8 @@ static LLVMValueRef build_buffer_load(struct si_shader_context *ctx,
 			                       "");
 		}
 
-		snprintf(name, sizeof(name), "llvm.amdgcn.buffer.load.%s",
-		         type_names[func]);
+		snprintf(name, sizeof(name), "llvm.amdgcn.buffer.load.%s%s",
+		         is_format ? "format." : "", type_names[func]);
 
 		return lp_build_intrinsic(gallivm->builder, name, types[func], args,
 		                          ARRAY_SIZE(args), LP_FUNC_ATTR_READONLY);
@@ -889,14 +921,14 @@ static LLVMValueRef buffer_load(struct lp_build_tgsi_context *bld_base,
 
 	if (swizzle == ~0) {
 		value = build_buffer_load(ctx, buffer, 4, NULL, base, offset,
-		                          0, 1, 0);
+		                          0, 1, 0, false);
 
 		return LLVMBuildBitCast(gallivm->builder, value, vec_type, "");
 	}
 
 	if (!tgsi_type_is_64bit(type)) {
 		value = build_buffer_load(ctx, buffer, 4, NULL, base, offset,
-		                          0, 1, 0);
+		                          0, 1, 0, false);
 
 		value = LLVMBuildBitCast(gallivm->builder, value, vec_type, "");
 		return LLVMBuildExtractElement(gallivm->builder, value,
@@ -904,10 +936,10 @@ static LLVMValueRef buffer_load(struct lp_build_tgsi_context *bld_base,
 	}
 
 	value = build_buffer_load(ctx, buffer, 1, NULL, base, offset,
-	                          swizzle * 4, 1, 0);
+	                          swizzle * 4, 1, 0, false);
 
 	value2 = build_buffer_load(ctx, buffer, 1, NULL, base, offset,
-	                           swizzle * 4 + 4, 1, 0);
+	                           swizzle * 4 + 4, 1, 0, false);
 
 	return si_llvm_emit_fetch_64bit(bld_base, type, value, value2);
 }
@@ -4779,11 +4811,10 @@ static void build_tex_intrinsic(const struct lp_build_tgsi_action *action,
 	const char *infix = "";
 
 	if (target == TGSI_TEXTURE_BUFFER) {
-		emit_data->output[emit_data->chan] = lp_build_intrinsic(
-			base->gallivm->builder,
-			"llvm.SI.vs.load.input", emit_data->dst_type,
-			emit_data->args, emit_data->arg_count,
-			LP_FUNC_ATTR_READNONE);
+		emit_data->output[emit_data->chan] =
+			build_vs_load_input(ctx, emit_data->args[0],
+					    emit_data->args[2],
+					    emit_data->args[1]);
 		return;
 	}
 
-- 
2.7.4