| // Copyright (c) 2015-2016 The Khronos Group Inc. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| // Performs validation on instructions that appear inside of a SPIR-V block. |
| |
| #include "validate.h" |
| |
| #include <algorithm> |
| #include <cassert> |
| |
| #include <sstream> |
| #include <string> |
| |
| #include "diagnostic.h" |
| #include "enum_set.h" |
| #include "opcode.h" |
| #include "operand.h" |
| #include "spirv_definition.h" |
| #include "val/function.h" |
| #include "val/validation_state.h" |
| |
| using libspirv::AssemblyGrammar; |
| using libspirv::CapabilitySet; |
| using libspirv::DiagnosticStream; |
| using libspirv::ValidationState_t; |
| |
| namespace { |
| |
| std::string ToString(const CapabilitySet& capabilities, |
| const AssemblyGrammar& grammar) { |
| std::stringstream ss; |
| capabilities.ForEach([&grammar, &ss](SpvCapability cap) { |
| spv_operand_desc desc; |
| if (SPV_SUCCESS == |
| grammar.lookupOperand(SPV_OPERAND_TYPE_CAPABILITY, cap, &desc)) |
| ss << desc->name << " "; |
| else |
| ss << cap << " "; |
| }); |
| return ss.str(); |
| } |
| |
| // Reports a missing-capability error to _'s diagnostic stream and returns |
| // SPV_ERROR_INVALID_CAPABILITY. |
| spv_result_t CapabilityError(ValidationState_t& _, int which_operand, |
| SpvOp opcode, |
| const std::string& required_capabilities) { |
| return _.diag(SPV_ERROR_INVALID_CAPABILITY) |
| << "Operand " << which_operand << " of " << spvOpcodeString(opcode) |
| << " requires one of these capabilities: " << required_capabilities; |
| } |
| |
| // Returns an operand's required capabilities. |
| CapabilitySet RequiredCapabilities(const AssemblyGrammar& grammar, |
| spv_operand_type_t type, uint32_t operand) { |
| // Mere mention of PointSize, ClipDistance, or CullDistance in a Builtin |
| // decoration does not require the associated capability. The use of such |
| // a variable value should trigger the capability requirement, but that's |
| // not implemented yet. This rule is independent of target environment. |
| // See https://github.com/KhronosGroup/SPIRV-Tools/issues/365 |
| if (type == SPV_OPERAND_TYPE_BUILT_IN) { |
| switch (operand) { |
| case SpvBuiltInPointSize: |
| case SpvBuiltInClipDistance: |
| case SpvBuiltInCullDistance: |
| return CapabilitySet(); |
| default: |
| break; |
| } |
| } |
| |
| spv_operand_desc operand_desc; |
| if (SPV_SUCCESS == grammar.lookupOperand(type, operand, &operand_desc)) { |
| return operand_desc->capabilities; |
| } |
| |
| return CapabilitySet(); |
| } |
| |
| } // namespace |
| |
| namespace libspirv { |
| |
| spv_result_t CapCheck(ValidationState_t& _, |
| const spv_parsed_instruction_t* inst) { |
| spv_opcode_desc opcode_desc; |
| const SpvOp opcode = static_cast<SpvOp>(inst->opcode); |
| if (SPV_SUCCESS == _.grammar().lookupOpcode(opcode, &opcode_desc) && |
| !_.HasAnyOf(opcode_desc->capabilities)) |
| return _.diag(SPV_ERROR_INVALID_CAPABILITY) |
| << "Opcode " << spvOpcodeString(opcode) |
| << " requires one of these capabilities: " |
| << ToString(opcode_desc->capabilities, _.grammar()); |
| for (int i = 0; i < inst->num_operands; ++i) { |
| const auto& operand = inst->operands[i]; |
| const auto word = inst->words[operand.offset]; |
| if (spvOperandIsConcreteMask(operand.type)) { |
| // Check for required capabilities for each bit position of the mask. |
| for (uint32_t mask_bit = 0x80000000; mask_bit; mask_bit >>= 1) { |
| if (word & mask_bit) { |
| const auto caps = |
| RequiredCapabilities(_.grammar(), operand.type, mask_bit); |
| if (!_.HasAnyOf(caps)) { |
| return CapabilityError(_, i + 1, opcode, |
| ToString(caps, _.grammar())); |
| } |
| } |
| } |
| } else if (spvIsIdType(operand.type)) { |
| // TODO(dneto): Check the value referenced by this Id, if we can compute |
| // it. For now, just punt, to fix issue 248: |
| // https://github.com/KhronosGroup/SPIRV-Tools/issues/248 |
| } else { |
| // Check the operand word as a whole. |
| const auto caps = RequiredCapabilities(_.grammar(), operand.type, word); |
| if (!_.HasAnyOf(caps)) { |
| return CapabilityError(_, i + 1, opcode, ToString(caps, _.grammar())); |
| } |
| } |
| } |
| return SPV_SUCCESS; |
| } |
| |
| // Checks that the Resuld <id> is within the valid bound. |
| spv_result_t LimitCheckIdBound(ValidationState_t& _, |
| const spv_parsed_instruction_t* inst) { |
| if (inst->result_id >= _.getIdBound()) { |
| return _.diag(SPV_ERROR_INVALID_BINARY) |
| << "Result <id> '" << inst->result_id |
| << "' must be less than the ID bound '" << _.getIdBound() << "'."; |
| } |
| return SPV_SUCCESS; |
| } |
| |
| // Checks that the number of OpTypeStruct members is within the limit. |
| spv_result_t LimitCheckStruct(ValidationState_t& _, |
| const spv_parsed_instruction_t* inst) { |
| if (SpvOpTypeStruct != inst->opcode) { |
| return SPV_SUCCESS; |
| } |
| |
| // Number of members is the number of operands of the instruction minus 1. |
| // One operand is the result ID. |
| const uint16_t limit = 0x3fff; |
| if (inst->num_operands - 1 > limit) { |
| return _.diag(SPV_ERROR_INVALID_BINARY) |
| << "Number of OpTypeStruct members (" << inst->num_operands - 1 |
| << ") has exceeded the limit (" << limit << ")."; |
| } |
| |
| // Section 2.17 of SPIRV Spec specifies that the "Structure Nesting Depth" |
| // must be less than or equal to 255. |
| // This is interpreted as structures including other structures as members. |
| // The code does not follow pointers or look into arrays to see if we reach a |
| // structure downstream. |
| // The nesting depth of a struct is 1+(largest depth of any member). |
| // Scalars are at depth 0. |
| uint32_t max_member_depth = 0; |
| // Struct members start at word 2 of OpTypeStruct instruction. |
| for (size_t word_i = 2; word_i < inst->num_words; ++word_i) { |
| auto member = inst->words[word_i]; |
| auto memberTypeInstr = _.FindDef(member); |
| if (memberTypeInstr && SpvOpTypeStruct == memberTypeInstr->opcode()) { |
| max_member_depth = std::max( |
| max_member_depth, _.struct_nesting_depth(memberTypeInstr->id())); |
| } |
| } |
| |
| const uint32_t depth_limit = 255; |
| const uint32_t cur_depth = 1 + max_member_depth; |
| _.set_struct_nesting_depth(inst->result_id, cur_depth); |
| if (cur_depth > depth_limit) { |
| return _.diag(SPV_ERROR_INVALID_BINARY) |
| << "Structure Nesting Depth may not be larger than " << depth_limit |
| << ". Found " << cur_depth << "."; |
| } |
| return SPV_SUCCESS; |
| } |
| |
| // Checks that the number of (literal, label) pairs in OpSwitch is within the |
| // limit. |
| spv_result_t LimitCheckSwitch(ValidationState_t& _, |
| const spv_parsed_instruction_t* inst) { |
| if (SpvOpSwitch == inst->opcode) { |
| // The instruction syntax is as follows: |
| // OpSwitch <selector ID> <Default ID> literal label literal label ... |
| // literal,label pairs come after the first 2 operands. |
| // It is guaranteed at this point that num_operands is an even numner. |
| unsigned int num_pairs = (inst->num_operands - 2) / 2; |
| const unsigned int num_pairs_limit = 16383; |
| if (num_pairs > num_pairs_limit) { |
| return _.diag(SPV_ERROR_INVALID_BINARY) |
| << "Number of (literal, label) pairs in OpSwitch (" << num_pairs |
| << ") exceeds the limit (" << num_pairs_limit << ")."; |
| } |
| } |
| return SPV_SUCCESS; |
| } |
| |
| // Ensure the number of variables of the given class does not exceed the limit. |
| spv_result_t LimitCheckNumVars(ValidationState_t& _, |
| const SpvStorageClass storage_class) { |
| if (SpvStorageClassFunction == storage_class) { |
| _.incrementNumLocalVars(); |
| const uint32_t num_local_vars_limit = 0x7FFFF; |
| if (_.num_local_vars() > num_local_vars_limit) { |
| return _.diag(SPV_ERROR_INVALID_BINARY) |
| << "Number of local variables ('Function' Storage Class) " |
| "exceeded the valid limit (" |
| << num_local_vars_limit << ")."; |
| } |
| } else { |
| _.incrementNumGlobalVars(); |
| const uint32_t num_global_vars_limit = 0xFFFF; |
| if (_.num_global_vars() > num_global_vars_limit) { |
| return _.diag(SPV_ERROR_INVALID_BINARY) |
| << "Number of Global Variables (Storage Class other than " |
| "'Function') exceeded the valid limit (" |
| << num_global_vars_limit << ")."; |
| } |
| } |
| return SPV_SUCCESS; |
| } |
| |
| spv_result_t InstructionPass(ValidationState_t& _, |
| const spv_parsed_instruction_t* inst) { |
| const SpvOp opcode = static_cast<SpvOp>(inst->opcode); |
| if (opcode == SpvOpCapability) |
| _.RegisterCapability( |
| static_cast<SpvCapability>(inst->words[inst->operands[0].offset])); |
| if (opcode == SpvOpMemoryModel) { |
| _.set_addressing_model( |
| static_cast<SpvAddressingModel>(inst->words[inst->operands[0].offset])); |
| _.set_memory_model( |
| static_cast<SpvMemoryModel>(inst->words[inst->operands[1].offset])); |
| } |
| if (opcode == SpvOpVariable) { |
| const auto storage_class = |
| static_cast<SpvStorageClass>(inst->words[inst->operands[2].offset]); |
| if (auto error = LimitCheckNumVars(_, storage_class)) { |
| return error; |
| } |
| if (storage_class == SpvStorageClassGeneric) |
| return _.diag(SPV_ERROR_INVALID_BINARY) |
| << "OpVariable storage class cannot be Generic"; |
| if (_.current_layout_section() == kLayoutFunctionDefinitions) { |
| if (storage_class != SpvStorageClassFunction) { |
| return _.diag(SPV_ERROR_INVALID_LAYOUT) |
| << "Variables must have a function[7] storage class inside" |
| " of a function"; |
| } |
| if (_.current_function().IsFirstBlock( |
| _.current_function().current_block()->id()) == false) { |
| return _.diag(SPV_ERROR_INVALID_CFG) << "Variables can only be defined " |
| "in the first block of a " |
| "function"; |
| } |
| } else { |
| if (storage_class == SpvStorageClassFunction) { |
| return _.diag(SPV_ERROR_INVALID_LAYOUT) |
| << "Variables can not have a function[7] storage class " |
| "outside of a function"; |
| } |
| } |
| } |
| |
| if (auto error = CapCheck(_, inst)) return error; |
| if (auto error = LimitCheckIdBound(_, inst)) return error; |
| if (auto error = LimitCheckStruct(_, inst)) return error; |
| if (auto error = LimitCheckSwitch(_, inst)) return error; |
| |
| // All instruction checks have passed. |
| return SPV_SUCCESS; |
| } |
| } // namespace libspirv |
