SPIRV-Tools/source/opt/flatten_decoration_pass.cpp
Alan Baker a771713e42 Adding an unique id to Instruction generated by IRContext
Each instruction is given an unique id that can be used for ordering
purposes. The ids are generated via the IRContext.

Major changes:
* Instructions now contain a uint32_t for unique id and a cached context
pointer
 * Most constructors have been modified to take a context as input
 * unfortunately I cannot remove the default and copy constructors, but
 developers should avoid these
* Added accessors to parents of basic block and function
* Removed the copy constructors for BasicBlock and Function and replaced
them with Clone functions
* Reworked BuildModule to return an IRContext owning the built module
 * Since all instructions require a context, the context now becomes the
basic unit for IR
* Added a constructor to context to create an owned module internally
* Replaced uses of Instruction's copy constructor with Clone whereever I
found them
* Reworked the linker functionality to perform clones into a different
context instead of moves
* Updated many tests to be consistent with the above changes
 * Still need to add new tests to cover added functionality
* Added comparison operators to Instruction
* Added an internal option to LinkerOptions to verify merged ids are
unique
* Added a test for the linker to verify merged ids are unique

* Updated MergeReturnPass to supply a context
* Updated DecorationManager to supply a context for cloned decorations

* Reworked several portions of the def use tests in anticipation of next
set of changes
2017-11-20 17:49:10 -05:00

168 lines
6.1 KiB
C++

// Copyright (c) 2017 Google 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.
#include "flatten_decoration_pass.h"
#include "ir_context.h"
#include <cassert>
#include <unordered_map>
#include <unordered_set>
#include <vector>
namespace spvtools {
namespace opt {
using ir::Instruction;
using ir::Operand;
using Words = std::vector<uint32_t>;
using OrderedUsesMap = std::unordered_map<uint32_t, Words>;
Pass::Status FlattenDecorationPass::Process(ir::IRContext* c) {
InitializeProcessing(c);
bool modified = false;
// The target Id of OpDecorationGroup instructions.
// We have to track this separately from its uses, in case it
// has no uses.
std::unordered_set<uint32_t> group_ids;
// Maps a decoration group Id to its GroupDecorate targets, in order
// of appearance.
OrderedUsesMap normal_uses;
// Maps a decoration group Id to its GroupMemberDecorate targets and
// their indices, in of appearance.
OrderedUsesMap member_uses;
auto annotations = context()->annotations();
// On the first pass, record each OpDecorationGroup with its ordered uses.
// Rely on unordered_map::operator[] to create its entries on first access.
for (const auto& inst : annotations) {
switch (inst.opcode()) {
case SpvOp::SpvOpDecorationGroup:
group_ids.insert(inst.result_id());
break;
case SpvOp::SpvOpGroupDecorate: {
Words& words = normal_uses[inst.GetSingleWordInOperand(0)];
for (uint32_t i = 1; i < inst.NumInOperandWords(); i++) {
words.push_back(inst.GetSingleWordInOperand(i));
}
} break;
case SpvOp::SpvOpGroupMemberDecorate: {
Words& words = member_uses[inst.GetSingleWordInOperand(0)];
for (uint32_t i = 1; i < inst.NumInOperandWords(); i++) {
words.push_back(inst.GetSingleWordInOperand(i));
}
} break;
default:
break;
}
}
// On the second pass, replace OpDecorationGroup and its uses with
// equivalent normal and struct member uses.
auto inst_iter = annotations.begin();
// We have to re-evaluate the end pointer
while (inst_iter != context()->annotations().end()) {
// Should we replace this instruction?
bool replace = false;
switch (inst_iter->opcode()) {
case SpvOp::SpvOpDecorationGroup:
case SpvOp::SpvOpGroupDecorate:
case SpvOp::SpvOpGroupMemberDecorate:
replace = true;
break;
case SpvOp::SpvOpDecorate: {
// If this decoration targets a group, then replace it
// by sets of normal and member decorations.
const uint32_t group = inst_iter->GetSingleWordOperand(0);
const auto normal_uses_iter = normal_uses.find(group);
if (normal_uses_iter != normal_uses.end()) {
for (auto target : normal_uses[group]) {
std::unique_ptr<Instruction> new_inst(inst_iter->Clone(context()));
new_inst->SetInOperand(0, Words{target});
inst_iter = inst_iter.InsertBefore(std::move(new_inst));
++inst_iter;
replace = true;
}
}
const auto member_uses_iter = member_uses.find(group);
if (member_uses_iter != member_uses.end()) {
const Words& member_id_pairs = (*member_uses_iter).second;
// The collection is a sequence of pairs.
assert((member_id_pairs.size() % 2) == 0);
for (size_t i = 0; i < member_id_pairs.size(); i += 2) {
// Make an OpMemberDecorate instruction for each (target, member)
// pair.
const uint32_t target = member_id_pairs[i];
const uint32_t member = member_id_pairs[i + 1];
std::vector<Operand> operands;
operands.push_back(Operand(SPV_OPERAND_TYPE_ID, {target}));
operands.push_back(
Operand(SPV_OPERAND_TYPE_LITERAL_INTEGER, {member}));
auto decoration_operands_iter = inst_iter->begin();
decoration_operands_iter++; // Skip the group target.
operands.insert(operands.end(), decoration_operands_iter,
inst_iter->end());
std::unique_ptr<Instruction> new_inst(new Instruction(
context(), SpvOp::SpvOpMemberDecorate, 0, 0, operands));
inst_iter = inst_iter.InsertBefore(std::move(new_inst));
++inst_iter;
replace = true;
}
}
// If this is an OpDecorate targeting the OpDecorationGroup itself,
// remove it even if that decoration group itself is not the target of
// any OpGroupDecorate or OpGroupMemberDecorate.
if (!replace && group_ids.count(group)) {
replace = true;
}
} break;
default:
break;
}
if (replace) {
inst_iter = inst_iter.Erase();
modified = true;
} else {
// Handle the case of decorations unrelated to decoration groups.
++inst_iter;
}
}
// Remove OpName instructions which reference the removed group decorations.
// An OpDecorationGroup instruction might not have been used by an
// OpGroupDecorate or OpGroupMemberDecorate instruction.
if (!group_ids.empty()) {
for (auto debug_inst_iter = context()->debug2_begin();
debug_inst_iter != context()->debug2_end();) {
if (debug_inst_iter->opcode() == SpvOp::SpvOpName) {
const uint32_t target = debug_inst_iter->GetSingleWordOperand(0);
if (group_ids.count(target)) {
debug_inst_iter = debug_inst_iter.Erase();
modified = true;
} else {
++debug_inst_iter;
}
}
}
}
return modified ? Status::SuccessWithChange : Status::SuccessWithoutChange;
}
} // namespace opt
} // namespace spvtools