SPIRV-Tools/source/validate_instruction.cpp
Ehsan Nasiri 23af06c3a3 Validator support for Variable Pointer extension.
If the variable_pointer extension is used:

* OpLoad's pointer argument may be the result of any of the following:
 * OpSelect
 * OpPhi
 * OpFunctionCall
 * OpPtrAccessChain
 * OpCopyObject
 * OpLoad
 * OpConstantNull

* Return value of a function may be a pointer.

* It is valid to use a pointer as the return value of a function.

* OpStore should allow a variable pointer argument.
2017-04-07 09:49:48 -04:00

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18 KiB
C++

// 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 "binary.h"
#include "diagnostic.h"
#include "enum_set.h"
#include "enum_string_mapping.h"
#include "extensions.h"
#include "opcode.h"
#include "operand.h"
#include "spirv_definition.h"
#include "spirv_validator_options.h"
#include "util/string_utils.h"
#include "val/function.h"
#include "val/validation_state.h"
using libspirv::AssemblyGrammar;
using libspirv::CapabilitySet;
using libspirv::DiagnosticStream;
using libspirv::ExtensionSet;
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 ValidationState_t& state,
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;
}
} else if (type == SPV_OPERAND_TYPE_FP_ROUNDING_MODE) {
// Allow all FP rounding modes if requested
if (state.features().free_fp_rounding_mode) {
return CapabilitySet();
}
}
spv_operand_desc operand_desc;
const auto ret = state.grammar().lookupOperand(type, operand, &operand_desc);
if (ret == SPV_SUCCESS) {
CapabilitySet result = operand_desc->capabilities;
// Allow FPRoundingMode decoration if requested
if (state.features().free_fp_rounding_mode &&
type == SPV_OPERAND_TYPE_DECORATION &&
operand_desc->value == SpvDecorationFPRoundingMode) {
return CapabilitySet();
}
return result;
}
return CapabilitySet();
}
// 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);
return operand_desc->extensions;
}
return ExtensionSet();
}
} // namespace
namespace libspirv {
spv_result_t CapabilityCheck(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) &&
!_.HasAnyOfCapabilities(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(_, operand.type, mask_bit);
if (!_.HasAnyOfCapabilities(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(_, operand.type, word);
if (!_.HasAnyOfCapabilities(caps)) {
return CapabilityError(_, i + 1, opcode, ToString(caps, _.grammar()));
}
}
}
return SPV_SUCCESS;
}
// Checks that all required extensions were declared in the module.
spv_result_t ExtensionCheck(ValidationState_t& _,
const spv_parsed_instruction_t* inst) {
const SpvOp opcode = static_cast<SpvOp>(inst->opcode);
for (size_t operand_index = 0; operand_index < inst->num_operands;
++operand_index) {
const auto& operand = inst->operands[operand_index];
const uint32_t word = inst->words[operand.offset];
const ExtensionSet required_extensions =
RequiredExtensions(_, operand.type, word);
if (!_.HasAnyOfExtensions(required_extensions)) {
return _.diag(SPV_ERROR_MISSING_EXTENSION)
<< spvutils::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 is not reserved for future use.
spv_result_t ReservedCheck(ValidationState_t& _,
const spv_parsed_instruction_t* inst) {
const SpvOp opcode = static_cast<SpvOp>(inst->opcode);
switch (opcode) {
case SpvOpImageSparseSampleProjImplicitLod:
case SpvOpImageSparseSampleProjExplicitLod:
case SpvOpImageSparseSampleProjDrefImplicitLod:
case SpvOpImageSparseSampleProjDrefExplicitLod:
return _.diag(SPV_ERROR_INVALID_VALUE) << spvOpcodeString(opcode)
<< " is reserved for future use.";
default:
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 =
static_cast<uint16_t>(_.options()->universal_limits_.max_struct_members);
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 = _.options()->universal_limits_.max_struct_depth;
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 =
_.options()->universal_limits_.max_switch_branches;
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 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)
<< "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)
<< "Number of Global Variables (Storage Class other than "
"'Function') exceeded the valid limit ("
<< num_global_vars_limit << ").";
}
}
return SPV_SUCCESS;
}
// Registers necessary decoration(s) for the appropriate IDs based on the
// instruction.
spv_result_t RegisterDecorations(ValidationState_t& _,
const spv_parsed_instruction_t* inst) {
switch (inst->opcode) {
case SpvOpDecorate: {
const uint32_t target_id = inst->words[1];
const SpvDecoration dec_type = static_cast<SpvDecoration>(inst->words[2]);
std::vector<uint32_t> dec_params;
if (inst->num_words > 3) {
dec_params.insert(dec_params.end(), inst->words + 3,
inst->words + inst->num_words);
}
_.RegisterDecorationForId(target_id, Decoration(dec_type, dec_params));
break;
}
case SpvOpMemberDecorate: {
const uint32_t struct_id = inst->words[1];
const uint32_t index = inst->words[2];
const SpvDecoration dec_type = static_cast<SpvDecoration>(inst->words[3]);
std::vector<uint32_t> dec_params;
if (inst->num_words > 4) {
dec_params.insert(dec_params.end(), inst->words + 4,
inst->words + inst->num_words);
}
_.RegisterDecorationForId(struct_id,
Decoration(dec_type, dec_params, index));
break;
}
case SpvOpDecorationGroup: {
// We don't need to do anything right now. Assigning decorations to groups
// will be taken care of via OpGroupDecorate.
break;
}
case SpvOpGroupDecorate: {
// Word 1 is the group <id>. All subsequent words are target <id>s that
// are going to be decorated with the decorations.
const uint32_t decoration_group_id = inst->words[1];
std::vector<Decoration>& group_decorations =
_.id_decorations(decoration_group_id);
for (int i = 2; i < inst->num_words; ++i) {
const uint32_t target_id = inst->words[i];
_.RegisterDecorationsForId(target_id, group_decorations.begin(),
group_decorations.end());
}
break;
}
case SpvOpGroupMemberDecorate: {
// Word 1 is the Decoration Group <id> followed by (struct<id>,literal)
// pairs. All decorations of the group should be applied to all the struct
// members that are specified in the instructions.
const uint32_t decoration_group_id = inst->words[1];
std::vector<Decoration>& group_decorations =
_.id_decorations(decoration_group_id);
// Grammar checks ensures that the number of arguments to this instruction
// is an odd number: 1 decoration group + (id,literal) pairs.
for (int i = 2; i + 1 < inst->num_words; i = i + 2) {
const uint32_t struct_id = inst->words[i];
const uint32_t index = inst->words[i + 1];
// ID validation phase ensures this is in fact a struct instruction and
// that the index is not out of bound.
_.RegisterDecorationsForStructMember(struct_id, index,
group_decorations.begin(),
group_decorations.end());
}
break;
}
default:
break;
}
return SPV_SUCCESS;
}
// Parses OpExtension instruction and logs warnings if unsuccessful.
void CheckIfKnownExtension(ValidationState_t& _,
const spv_parsed_instruction_t* inst) {
const std::string extension_str = GetExtensionString(inst);
Extension extension;
if (!GetExtensionFromString(extension_str, &extension)) {
_.diag(SPV_SUCCESS) << "Found unrecognized extension " << extension_str;
return;
}
}
spv_result_t InstructionPass(ValidationState_t& _,
const spv_parsed_instruction_t* inst) {
const SpvOp opcode = static_cast<SpvOp>(inst->opcode);
if (opcode == SpvOpExtension)
CheckIfKnownExtension(_, inst);
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(_, inst->result_id, 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";
}
}
}
// 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->words[inst->operands[2].offset] != 0u) {
return _.diag(SPV_ERROR_INVALID_BINARY) << "The Signedness in OpTypeInt "
"must always be 0 when Kernel "
"capability is used.";
}
// In order to validate decoration rules, we need to know all the decorations
// that are applied to any given <id>.
RegisterDecorations(_, inst);
if (auto error = ExtensionCheck(_, 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 = ReservedCheck(_, inst)) return error;
// All instruction checks have passed.
return SPV_SUCCESS;
}
} // namespace libspirv