From: Mikko Rasa <tdb@tdb.fi>
Date: Wed, 28 Apr 2021 11:38:55 +0000 (+0300)
Subject: Implement textureSize as a visitor function in the SPIR-V generator
X-Git-Url: http://git.tdb.fi/?a=commitdiff_plain;h=ece3438c6a1630ada39cc01ae3d54b27aacdd663;p=libs%2Fgl.git

Implement textureSize as a visitor function in the SPIR-V generator

It requires an image as an operand, not a sampled image.
---

diff --git a/source/glsl/spirv.cpp b/source/glsl/spirv.cpp
index 33da0d5c..186521c5 100644
--- a/source/glsl/spirv.cpp
+++ b/source/glsl/spirv.cpp
@@ -107,7 +107,7 @@ const SpirVGenerator::BuiltinFunctionInfo SpirVGenerator::builtin_functions[] =
 	{ "findLSB", "u", "GLSL.std.450", GLSL450_FIND_I_LSB, { 1 }, 0, 0 },
 	{ "findMSB", "i", "GLSL.std.450", GLSL450_FIND_S_MSB, { 1 }, 0, 0 },
 	{ "findMSB", "u", "GLSL.std.450", GLSL450_FIND_U_MSB, { 1 }, 0, 0 },
-	{ "textureSize", "", "", OP_IMAGE_QUERY_SIZE_LOD, { 1, 2 }, CAP_IMAGE_QUERY, 0 },
+	{ "textureSize", "", "", 0, { }, CAP_IMAGE_QUERY, &SpirVGenerator::visit_builtin_texture_query },
 	{ "texture", "", "", 0, { }, 0, &SpirVGenerator::visit_builtin_texture },
 	{ "textureLod", "", "", 0, { }, 0, &SpirVGenerator::visit_builtin_texture },
 	{ "texelFetch", "", "", 0, { }, 0, &SpirVGenerator::visit_builtin_texel_fetch },
@@ -1284,6 +1284,36 @@ void SpirVGenerator::visit_builtin_matrix_comp_mult(FunctionCall &call, const ve
 	r_expression_result_id = write_construct(get_id(*call.type), column_ids, n_columns);
 }
 
+void SpirVGenerator::visit_builtin_texture_query(FunctionCall &call, const vector<Id> &argument_ids)
+{
+	if(argument_ids.size()<1)
+		throw internal_error("invalid texture query call");
+
+	Opcode opcode;
+	if(call.name=="textureSize")
+		opcode = OP_IMAGE_QUERY_SIZE_LOD;
+	else
+		throw internal_error("invalid texture query call");
+
+	ImageTypeDeclaration &image_arg0 = dynamic_cast<ImageTypeDeclaration &>(*call.arguments[0]->type);
+
+	Id image_id;
+	if(image_arg0.sampled)
+	{
+		Id image_type_id = get_item(image_type_ids, get_id(image_arg0));
+		image_id = write_expression(OP_IMAGE, image_type_id, argument_ids[0]);
+	}
+	else
+		image_id = argument_ids[0];
+
+	Id result_type_id = get_id(*call.type);
+	r_expression_result_id = begin_expression(opcode, result_type_id, argument_ids.size());
+	writer.write(image_id);
+	for(unsigned i=1; i<argument_ids.size(); ++i)
+		writer.write(argument_ids[i]);
+	end_expression(opcode);
+}
+
 void SpirVGenerator::visit_builtin_texture(FunctionCall &call, const vector<Id> &argument_ids)
 {
 	if(argument_ids.size()<2)
@@ -1468,6 +1498,7 @@ void SpirVGenerator::visit(ImageTypeDeclaration &image)
 	{
 		writer.write_op_name(type_id, image.name);
 		writer.write_op(content.globals, OP_TYPE_SAMPLED_IMAGE, type_id, image_id);
+		insert_unique(image_type_ids, type_id, image_id);
 	}
 
 	if(image.dimensions==ImageTypeDeclaration::ONE)
diff --git a/source/glsl/spirv.h b/source/glsl/spirv.h
index c023adae..f18bf61c 100644
--- a/source/glsl/spirv.h
+++ b/source/glsl/spirv.h
@@ -80,6 +80,7 @@ private:
 	std::map<Node *, Declaration> declared_ids;
 	std::map<std::string, Id> declared_uniform_ids;
 	std::map<TypeKey, Id> standard_type_ids;
+	std::map<Id, Id> image_type_ids;
 	std::map<TypeKey, Id> array_type_ids;
 	std::map<TypeKey, Id> pointer_type_ids;
 	std::map<std::string, Id> function_type_ids;
@@ -149,6 +150,7 @@ private:
 	virtual void visit(FunctionCall &);
 	void visit_constructor(FunctionCall &, const std::vector<Id> &, bool);
 	void visit_builtin_matrix_comp_mult(FunctionCall &, const std::vector<Id> &);
+	void visit_builtin_texture_query(FunctionCall &, const std::vector<Id> &);
 	void visit_builtin_texture(FunctionCall &, const std::vector<Id> &);
 	void visit_builtin_texel_fetch(FunctionCall &, const std::vector<Id> &);
 	void visit_builtin_interpolate(FunctionCall &, const std::vector<Id> &);
diff --git a/source/glsl/spirvconstants.h b/source/glsl/spirvconstants.h
index 04d28349..3d424844 100644
--- a/source/glsl/spirvconstants.h
+++ b/source/glsl/spirvconstants.h
@@ -64,6 +64,7 @@ enum SpirVOpcode
 	OP_IMAGE_SAMPLE_DREF_IMPLICIT_LOD = 89,
 	OP_IMAGE_SAMPLE_DREF_EXPLICIT_LOD = 89,
 	OP_IMAGE_FETCH = 95,
+	OP_IMAGE = 100,
 	OP_IMAGE_QUERY_SIZE_LOD = 103,
 	OP_CONVERT_F_TO_U = 109,
 	OP_CONVERT_F_TO_S = 110,