1 // Copyright (c) 2017 Google Inc.
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 // http://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14
15 #include "source/opt/compact_ids_pass.h"
16
17 #include <cassert>
18 #include <unordered_map>
19
20 #include "source/opt/ir_context.h"
21
22 namespace spvtools {
23 namespace opt {
24 namespace {
25
26 // Returns the remapped id of |id| from |result_id_mapping|. If the remapped
27 // id does not exist, adds a new one to |result_id_mapping| and returns it.
GetRemappedId(std::unordered_map<uint32_t,uint32_t> * result_id_mapping,uint32_t id)28 uint32_t GetRemappedId(
29 std::unordered_map<uint32_t, uint32_t>* result_id_mapping, uint32_t id) {
30 auto it = result_id_mapping->find(id);
31 if (it == result_id_mapping->end()) {
32 const uint32_t new_id =
33 static_cast<uint32_t>(result_id_mapping->size()) + 1;
34 const auto insertion_result = result_id_mapping->emplace(id, new_id);
35 it = insertion_result.first;
36 assert(insertion_result.second);
37 }
38 return it->second;
39 }
40
41 } // namespace
42
Process()43 Pass::Status CompactIdsPass::Process() {
44 bool modified = false;
45 std::unordered_map<uint32_t, uint32_t> result_id_mapping;
46
47 // Disable automatic DebugInfo analysis for the life of the CompactIds pass.
48 // The DebugInfo manager requires the SPIR-V to be valid to run, but this is
49 // not true at all times in CompactIds as it remaps all ids.
50 context()->InvalidateAnalyses(IRContext::kAnalysisDebugInfo);
51
52 context()->module()->ForEachInst(
53 [&result_id_mapping, &modified](Instruction* inst) {
54 auto operand = inst->begin();
55 while (operand != inst->end()) {
56 const auto type = operand->type;
57 if (spvIsIdType(type)) {
58 assert(operand->words.size() == 1);
59 uint32_t& id = operand->words[0];
60 uint32_t new_id = GetRemappedId(&result_id_mapping, id);
61 if (id != new_id) {
62 modified = true;
63 id = new_id;
64 // Update data cached in the instruction object.
65 if (type == SPV_OPERAND_TYPE_RESULT_ID) {
66 inst->SetResultId(id);
67 } else if (type == SPV_OPERAND_TYPE_TYPE_ID) {
68 inst->SetResultType(id);
69 }
70 }
71 }
72 ++operand;
73 }
74
75 uint32_t scope_id = inst->GetDebugScope().GetLexicalScope();
76 if (scope_id != kNoDebugScope) {
77 uint32_t new_id = GetRemappedId(&result_id_mapping, scope_id);
78 if (scope_id != new_id) {
79 inst->UpdateLexicalScope(new_id);
80 modified = true;
81 }
82 }
83 uint32_t inlinedat_id = inst->GetDebugInlinedAt();
84 if (inlinedat_id != kNoInlinedAt) {
85 uint32_t new_id = GetRemappedId(&result_id_mapping, inlinedat_id);
86 if (inlinedat_id != new_id) {
87 inst->UpdateDebugInlinedAt(new_id);
88 modified = true;
89 }
90 }
91 },
92 true);
93
94 if (context()->module()->id_bound() != result_id_mapping.size() + 1) {
95 modified = true;
96 context()->module()->SetIdBound(
97 static_cast<uint32_t>(result_id_mapping.size() + 1));
98 // There are ids in the feature manager that could now be invalid
99 context()->ResetFeatureManager();
100 }
101
102 return modified ? Status::SuccessWithChange : Status::SuccessWithoutChange;
103 }
104
105 } // namespace opt
106 } // namespace spvtools
107