// 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 "source/val/validate.h"
#include <algorithm>
#include <cassert>
#include <sstream>
#include <string>
#include <vector>
#include "source/binary.h"
#include "source/diagnostic.h"
#include "source/enum_set.h"
#include "source/enum_string_mapping.h"
#include "source/extensions.h"
#include "source/opcode.h"
#include "source/operand.h"
#include "source/spirv_constant.h"
#include "source/spirv_definition.h"
#include "source/spirv_target_env.h"
#include "source/spirv_validator_options.h"
#include "source/util/string_utils.h"
#include "source/val/function.h"
#include "source/val/validation_state.h"
namespace spvtools {
namespace val {
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();
}
// Returns capabilities that enable an opcode. An empty result is interpreted
// as no prohibition of use of the opcode. If the result is non-empty, then
// the opcode may only be used if at least one of the capabilities is specified
// by the module.
CapabilitySet EnablingCapabilitiesForOp(const ValidationState_t& state,
SpvOp opcode) {
// Exceptions for SPV_AMD_shader_ballot
switch (opcode) {
// Normally these would require Group capability
case SpvOpGroupIAddNonUniformAMD:
case SpvOpGroupFAddNonUniformAMD:
case SpvOpGroupFMinNonUniformAMD:
case SpvOpGroupUMinNonUniformAMD:
case SpvOpGroupSMinNonUniformAMD:
case SpvOpGroupFMaxNonUniformAMD:
case SpvOpGroupUMaxNonUniformAMD:
case SpvOpGroupSMaxNonUniformAMD:
if (state.HasExtension(kSPV_AMD_shader_ballot)) return CapabilitySet();
break;
default:
break;
}
// Look it up in the grammar
spv_opcode_desc opcode_desc = {};
if (SPV_SUCCESS == state.grammar().lookupOpcode(opcode, &opcode_desc)) {
return state.grammar().filterCapsAgainstTargetEnv(
opcode_desc->capabilities, opcode_desc->numCapabilities);
}
return CapabilitySet();
}
// Returns SPV_SUCCESS if the given operand is enabled by capabilities declared
// in the module. Otherwise issues an error message and returns
// SPV_ERROR_INVALID_CAPABILITY.
spv_result_t CheckRequiredCapabilities(ValidationState_t& state,
const Instruction* inst,
size_t which_operand,
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 SPV_SUCCESS;
default:
break;
}
} else if (type == SPV_OPERAND_TYPE_FP_ROUNDING_MODE) {
// Allow all FP rounding modes if requested
if (state.features().free_fp_rounding_mode) {
return SPV_SUCCESS;
}
} else if (type == SPV_OPERAND_TYPE_GROUP_OPERATION &&
state.features().group_ops_reduce_and_scans &&
(operand <= uint32_t(SpvGroupOperationExclusiveScan))) {
// Allow certain group operations if requested.
return SPV_SUCCESS;
}
CapabilitySet enabling_capabilities;
spv_operand_desc operand_desc = nullptr;
const auto lookup_result =
state.grammar().lookupOperand(type, operand, &operand_desc);
if (lookup_result == SPV_SUCCESS) {
// Allow FPRoundingMode decoration if requested.
if (type == SPV_OPERAND_TYPE_DECORATION &&
operand_desc->value == SpvDecorationFPRoundingMode) {
if (state.features().free_fp_rounding_mode) return SPV_SUCCESS;
// Vulkan API requires more capabilities on rounding mode.
if (spvIsVulkanEnv(state.context()->target_env)) {
enabling_capabilities.Add(SpvCapabilityStorageUniformBufferBlock16);
enabling_capabilities.Add(SpvCapabilityStorageUniform16);
enabling_capabilities.Add(SpvCapabilityStoragePushConstant16);
enabling_capabilities.Add(SpvCapabilityStorageInputOutput16);
}
} else {
enabling_capabilities = state.grammar().filterCapsAgainstTargetEnv(
operand_desc->capabilities, operand_desc->numCapabilities);
}
if (!state.HasAnyOfCapabilities(enabling_capabilities)) {
return state.diag(SPV_ERROR_INVALID_CAPABILITY, inst)
<< "Operand " << which_operand << " of "
<< spvOpcodeString(inst->opcode())
<< " requires one of these capabilities: "
<< ToString(enabling_capabilities, state.grammar());
}
}
return SPV_SUCCESS;
}
// Returns operand's required extensions.
ExtensionSet RequiredExtensions(const ValidationState_t& state,
spv_operand_type_t type, uint32_t operand) {
spv_operand_desc operand_desc;
if (state.grammar().lookupOperand(type, operand, &operand_desc) ==
SPV_SUCCESS) {
assert(operand_desc);
// If this operand is incorporated into core SPIR-V before or in the current
// target environment, we don't require extensions anymore.
if (spvVersionForTargetEnv(state.grammar().target_env()) >=
operand_desc->minVersion)
return {};
return {operand_desc->numExtensions, operand_desc->extensions};
}
return {};
}
// Returns SPV_ERROR_INVALID_BINARY and emits a diagnostic if the instruction
// is explicitly reserved in the SPIR-V core spec. Otherwise return
// SPV_SUCCESS.
spv_result_t ReservedCheck(ValidationState_t& _, const Instruction* inst) {
const SpvOp opcode = inst->opcode();
switch (opcode) {
// These instructions are enabled by a capability, but should never
// be used anyway.
case SpvOpImageSparseSampleProjImplicitLod:
case SpvOpImageSparseSampleProjExplicitLod:
case SpvOpImageSparseSampleProjDrefImplicitLod:
case SpvOpImageSparseSampleProjDrefExplicitLod: {
spv_opcode_desc inst_desc;
_.grammar().lookupOpcode(opcode, &inst_desc);
return _.diag(SPV_ERROR_INVALID_BINARY, inst)
<< "Invalid Opcode name 'Op" << inst_desc->name << "'";
}
default:
break;
}
return SPV_SUCCESS;
}
// Returns SPV_ERROR_INVALID_BINARY and emits a diagnostic if the instruction
// is invalid because of an execution environment constraint.
spv_result_t EnvironmentCheck(ValidationState_t& _, const Instruction* inst) {
const SpvOp opcode = inst->opcode();
switch (opcode) {
case SpvOpUndef:
if (_.features().bans_op_undef) {
return _.diag(SPV_ERROR_INVALID_BINARY, inst)
<< "OpUndef is disallowed";
}
break;
default:
break;
}
return SPV_SUCCESS;
}
// Returns SPV_ERROR_INVALID_CAPABILITY and emits a diagnostic if the
// instruction is invalid because the required capability isn't declared
// in the module.
spv_result_t CapabilityCheck(ValidationState_t& _, const Instruction* inst) {
const SpvOp opcode = inst->opcode();
CapabilitySet opcode_caps = EnablingCapabilitiesForOp(_, opcode);
if (!_.HasAnyOfCapabilities(opcode_caps)) {
return _.diag(SPV_ERROR_INVALID_CAPABILITY, inst)
<< "Opcode " << spvOpcodeString(opcode)
<< " requires one of these capabilities: "
<< ToString(opcode_caps, _.grammar());
}
for (size_t i = 0; i < inst->operands().size(); ++i) {
const auto& operand = inst->operand(i);
const auto word = inst->word(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) {
spv_result_t status =
CheckRequiredCapabilities(_, inst, i + 1, operand.type, mask_bit);
if (status != SPV_SUCCESS) return status;
}
}
} 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.
spv_result_t status =
CheckRequiredCapabilities(_, inst, i + 1, operand.type, word);
if (status != SPV_SUCCESS) return status;
}
}
return SPV_SUCCESS;
}
// Checks that all extensions required by the given instruction's operands were
// declared in the module.
spv_result_t ExtensionCheck(ValidationState_t& _, const Instruction* inst) {
const SpvOp opcode = inst->opcode();
for (size_t operand_index = 0; operand_index < inst->operands().size();
++operand_index) {
const auto& operand = inst->operand(operand_index);
const uint32_t word = inst->word(operand.offset);
const ExtensionSet required_extensions =
RequiredExtensions(_, operand.type, word);
if (!_.HasAnyOfExtensions(required_extensions)) {
return _.diag(SPV_ERROR_MISSING_EXTENSION, inst)
<< spvtools::utils::CardinalToOrdinal(operand_index + 1)
<< " operand of " << spvOpcodeString(opcode) << ": operand "
<< word << " requires one of these extensions: "
<< ExtensionSetToString(required_extensions);
}
}
return SPV_SUCCESS;
}
// Checks that the instruction can be used in this target environment's base
// version. Assumes that CapabilityCheck has checked direct capability
// dependencies for the opcode.
spv_result_t VersionCheck(ValidationState_t& _, const Instruction* inst) {
const auto opcode = inst->opcode();
spv_opcode_desc inst_desc;
const spv_result_t r = _.grammar().lookupOpcode(opcode, &inst_desc);
assert(r == SPV_SUCCESS);
(void)r;
const auto min_version = inst_desc->minVersion;
if (inst_desc->numCapabilities > 0u) {
// We already checked that the direct capability dependency has been
// satisfied. We don't need to check any further.
return SPV_SUCCESS;
}
ExtensionSet exts(inst_desc->numExtensions, inst_desc->extensions);
if (exts.IsEmpty()) {
// If no extensions can enable this instruction, then emit error messages
// only concerning core SPIR-V versions if errors happen.
if (min_version == ~0u) {
return _.diag(SPV_ERROR_WRONG_VERSION, inst)
<< spvOpcodeString(opcode) << " is reserved for future use.";
}
if (spvVersionForTargetEnv(_.grammar().target_env()) < min_version) {
return _.diag(SPV_ERROR_WRONG_VERSION, inst)
<< spvOpcodeString(opcode) << " requires "
<< spvTargetEnvDescription(
static_cast<spv_target_env>(min_version))
<< " at minimum.";
}
// Otherwise, we only error out when no enabling extensions are registered.
} else if (!_.HasAnyOfExtensions(exts)) {
if (min_version == ~0u) {
return _.diag(SPV_ERROR_MISSING_EXTENSION, inst)
<< spvOpcodeString(opcode)
<< " requires one of the following extensions: "
<< ExtensionSetToString(exts);
}
if (static_cast<uint32_t>(_.grammar().target_env()) < min_version) {
return _.diag(SPV_ERROR_WRONG_VERSION, inst)
<< spvOpcodeString(opcode) << " requires "
<< spvTargetEnvDescription(
static_cast<spv_target_env>(min_version))
<< " at minimum or one of the following extensions: "
<< ExtensionSetToString(exts);
}
}
return SPV_SUCCESS;
}
// Checks that the Resuld <id> is within the valid bound.
spv_result_t LimitCheckIdBound(ValidationState_t& _, const Instruction* inst) {
if (inst->id() >= _.getIdBound()) {
return _.diag(SPV_ERROR_INVALID_BINARY, inst)
<< "Result <id> '" << inst->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 Instruction* 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 =
static_cast<uint16_t>(_.options()->universal_limits_.max_struct_members);
if (inst->operands().size() - 1 > limit) {
return _.diag(SPV_ERROR_INVALID_BINARY, inst)
<< "Number of OpTypeStruct members (" << inst->operands().size() - 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->words().size(); ++word_i) {
auto member = inst->word(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 = _.options()->universal_limits_.max_struct_depth;
const uint32_t cur_depth = 1 + max_member_depth;
_.set_struct_nesting_depth(inst->id(), cur_depth);
if (cur_depth > depth_limit) {
return _.diag(SPV_ERROR_INVALID_BINARY, inst)
<< "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 Instruction* 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.
size_t num_pairs = (inst->operands().size() - 2) / 2;
const unsigned int num_pairs_limit =
_.options()->universal_limits_.max_switch_branches;
if (num_pairs > num_pairs_limit) {
return _.diag(SPV_ERROR_INVALID_BINARY, inst)
<< "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 uint32_t var_id,
const SpvStorageClass storage_class) {
if (SpvStorageClassFunction == storage_class) {
_.registerLocalVariable(var_id);
const uint32_t num_local_vars_limit =
_.options()->universal_limits_.max_local_variables;
if (_.num_local_vars() > num_local_vars_limit) {
return _.diag(SPV_ERROR_INVALID_BINARY, nullptr)
<< "Number of local variables ('Function' Storage Class) "
"exceeded the valid limit ("
<< num_local_vars_limit << ").";
}
} else {
_.registerGlobalVariable(var_id);
const uint32_t num_global_vars_limit =
_.options()->universal_limits_.max_global_variables;
if (_.num_global_vars() > num_global_vars_limit) {
return _.diag(SPV_ERROR_INVALID_BINARY, nullptr)
<< "Number of Global Variables (Storage Class other than "
"'Function') exceeded the valid limit ("
<< num_global_vars_limit << ").";
}
}
return SPV_SUCCESS;
}
// Parses OpExtension instruction and logs warnings if unsuccessful.
spv_result_t CheckIfKnownExtension(ValidationState_t& _,
const Instruction* inst) {
const std::string extension_str = GetExtensionString(&(inst->c_inst()));
Extension extension;
if (!GetExtensionFromString(extension_str.c_str(), &extension)) {
return _.diag(SPV_WARNING, inst)
<< "Found unrecognized extension " << extension_str;
}
return SPV_SUCCESS;
}
} // namespace
spv_result_t InstructionPass(ValidationState_t& _, const Instruction* inst) {
const SpvOp opcode = inst->opcode();
if (opcode == SpvOpExtension) {
CheckIfKnownExtension(_, inst);
} else if (opcode == SpvOpCapability) {
_.RegisterCapability(inst->GetOperandAs<SpvCapability>(0));
} else if (opcode == SpvOpMemoryModel) {
if (_.has_memory_model_specified()) {
return _.diag(SPV_ERROR_INVALID_LAYOUT, inst)
<< "OpMemoryModel should only be provided once.";
}
_.set_addressing_model(inst->GetOperandAs<SpvAddressingModel>(0));
_.set_memory_model(inst->GetOperandAs<SpvMemoryModel>(1));
if (_.memory_model() != SpvMemoryModelVulkanKHR &&
_.HasCapability(SpvCapabilityVulkanMemoryModelKHR)) {
return _.diag(SPV_ERROR_INVALID_DATA, inst)
<< "VulkanMemoryModelKHR capability must only be specified if the "
"VulkanKHR memory model is used.";
}
if (spvIsWebGPUEnv(_.context()->target_env)) {
if (_.addressing_model() != SpvAddressingModelLogical) {
return _.diag(SPV_ERROR_INVALID_DATA, inst)
<< "Addressing model must be Logical for WebGPU environment.";
}
if (_.memory_model() != SpvMemoryModelVulkanKHR) {
return _.diag(SPV_ERROR_INVALID_DATA, inst)
<< "Memory model must be VulkanKHR for WebGPU environment.";
}
}
} else if (opcode == SpvOpExecutionMode) {
const uint32_t entry_point = inst->word(1);
_.RegisterExecutionModeForEntryPoint(entry_point,
SpvExecutionMode(inst->word(2)));
} else if (opcode == SpvOpVariable) {
const auto storage_class = inst->GetOperandAs<SpvStorageClass>(2);
if (auto error = LimitCheckNumVars(_, inst->id(), storage_class)) {
return error;
}
if (storage_class == SpvStorageClassGeneric)
return _.diag(SPV_ERROR_INVALID_BINARY, inst)
<< "OpVariable storage class cannot be Generic";
if (_.current_layout_section() == kLayoutFunctionDefinitions) {
if (storage_class != SpvStorageClassFunction) {
return _.diag(SPV_ERROR_INVALID_LAYOUT, inst)
<< "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, inst)
<< "Variables can only be defined "
"in the first block of a "
"function";
}
} else {
if (storage_class == SpvStorageClassFunction) {
return _.diag(SPV_ERROR_INVALID_LAYOUT, inst)
<< "Variables can not have a function[7] storage class "
"outside of a function";
}
}
}
// SPIR-V Spec 2.16.3: Validation Rules for Kernel Capabilities: The
// Signedness in OpTypeInt must always be 0.
if (SpvOpTypeInt == inst->opcode() && _.HasCapability(SpvCapabilityKernel) &&
inst->GetOperandAs<uint32_t>(2) != 0u) {
return _.diag(SPV_ERROR_INVALID_BINARY, inst)
<< "The Signedness in OpTypeInt "
"must always be 0 when Kernel "
"capability is used.";
}
if (auto error = ExtensionCheck(_, inst)) return error;
if (auto error = ReservedCheck(_, inst)) return error;
if (auto error = EnvironmentCheck(_, inst)) return error;
if (auto error = CapabilityCheck(_, inst)) return error;
if (auto error = LimitCheckIdBound(_, inst)) return error;
if (auto error = LimitCheckStruct(_, inst)) return error;
if (auto error = LimitCheckSwitch(_, inst)) return error;
if (auto error = VersionCheck(_, inst)) return error;
// All instruction checks have passed.
return SPV_SUCCESS;
}
} // namespace val
} // namespace spvtools