Bug Summary

File:lib/Transforms/Instrumentation/ControlHeightReduction.cpp
Warning:line 1064, column 3
Forming reference to null pointer

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clang -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name ControlHeightReduction.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -analyzer-config-compatibility-mode=true -mrelocation-model pic -pic-level 2 -mthread-model posix -mframe-pointer=none -fmath-errno -masm-verbose -mconstructor-aliases -munwind-tables -fuse-init-array -target-cpu x86-64 -dwarf-column-info -debugger-tuning=gdb -ffunction-sections -fdata-sections -resource-dir /usr/lib/llvm-10/lib/clang/10.0.0 -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-10~svn374877/build-llvm/lib/Transforms/Instrumentation -I /build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation -I /build/llvm-toolchain-snapshot-10~svn374877/build-llvm/include -I /build/llvm-toolchain-snapshot-10~svn374877/include -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0/backward -internal-isystem /usr/local/include -internal-isystem /usr/lib/llvm-10/lib/clang/10.0.0/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O2 -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-comment -std=c++14 -fdeprecated-macro -fdebug-compilation-dir /build/llvm-toolchain-snapshot-10~svn374877/build-llvm/lib/Transforms/Instrumentation -fdebug-prefix-map=/build/llvm-toolchain-snapshot-10~svn374877=. -ferror-limit 19 -fmessage-length 0 -fvisibility-inlines-hidden -stack-protector 2 -fgnuc-version=4.2.1 -fobjc-runtime=gcc -fdiagnostics-show-option -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -faddrsig -o /tmp/scan-build-2019-10-15-233810-7101-1 -x c++ /build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp
1//===-- ControlHeightReduction.cpp - Control Height Reduction -------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This pass merges conditional blocks of code and reduces the number of
10// conditional branches in the hot paths based on profiles.
11//
12//===----------------------------------------------------------------------===//
13
14#include "llvm/Transforms/Instrumentation/ControlHeightReduction.h"
15#include "llvm/ADT/DenseMap.h"
16#include "llvm/ADT/DenseSet.h"
17#include "llvm/ADT/SmallVector.h"
18#include "llvm/ADT/StringSet.h"
19#include "llvm/Analysis/BlockFrequencyInfo.h"
20#include "llvm/Analysis/GlobalsModRef.h"
21#include "llvm/Analysis/OptimizationRemarkEmitter.h"
22#include "llvm/Analysis/ProfileSummaryInfo.h"
23#include "llvm/Analysis/RegionInfo.h"
24#include "llvm/Analysis/RegionIterator.h"
25#include "llvm/Analysis/ValueTracking.h"
26#include "llvm/IR/CFG.h"
27#include "llvm/IR/Dominators.h"
28#include "llvm/IR/IRBuilder.h"
29#include "llvm/IR/MDBuilder.h"
30#include "llvm/Support/BranchProbability.h"
31#include "llvm/Support/MemoryBuffer.h"
32#include "llvm/Transforms/Utils.h"
33#include "llvm/Transforms/Utils/BasicBlockUtils.h"
34#include "llvm/Transforms/Utils/Cloning.h"
35#include "llvm/Transforms/Utils/ValueMapper.h"
36
37#include <set>
38#include <sstream>
39
40using namespace llvm;
41
42#define DEBUG_TYPE"chr" "chr"
43
44#define CHR_DEBUG(X)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { X; } } while (false)
LLVM_DEBUG(X)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { X; } } while (false)
45
46static cl::opt<bool> ForceCHR("force-chr", cl::init(false), cl::Hidden,
47 cl::desc("Apply CHR for all functions"));
48
49static cl::opt<double> CHRBiasThreshold(
50 "chr-bias-threshold", cl::init(0.99), cl::Hidden,
51 cl::desc("CHR considers a branch bias greater than this ratio as biased"));
52
53static cl::opt<unsigned> CHRMergeThreshold(
54 "chr-merge-threshold", cl::init(2), cl::Hidden,
55 cl::desc("CHR merges a group of N branches/selects where N >= this value"));
56
57static cl::opt<std::string> CHRModuleList(
58 "chr-module-list", cl::init(""), cl::Hidden,
59 cl::desc("Specify file to retrieve the list of modules to apply CHR to"));
60
61static cl::opt<std::string> CHRFunctionList(
62 "chr-function-list", cl::init(""), cl::Hidden,
63 cl::desc("Specify file to retrieve the list of functions to apply CHR to"));
64
65static StringSet<> CHRModules;
66static StringSet<> CHRFunctions;
67
68static void parseCHRFilterFiles() {
69 if (!CHRModuleList.empty()) {
70 auto FileOrErr = MemoryBuffer::getFile(CHRModuleList);
71 if (!FileOrErr) {
72 errs() << "Error: Couldn't read the chr-module-list file " << CHRModuleList << "\n";
73 std::exit(1);
74 }
75 StringRef Buf = FileOrErr->get()->getBuffer();
76 SmallVector<StringRef, 0> Lines;
77 Buf.split(Lines, '\n');
78 for (StringRef Line : Lines) {
79 Line = Line.trim();
80 if (!Line.empty())
81 CHRModules.insert(Line);
82 }
83 }
84 if (!CHRFunctionList.empty()) {
85 auto FileOrErr = MemoryBuffer::getFile(CHRFunctionList);
86 if (!FileOrErr) {
87 errs() << "Error: Couldn't read the chr-function-list file " << CHRFunctionList << "\n";
88 std::exit(1);
89 }
90 StringRef Buf = FileOrErr->get()->getBuffer();
91 SmallVector<StringRef, 0> Lines;
92 Buf.split(Lines, '\n');
93 for (StringRef Line : Lines) {
94 Line = Line.trim();
95 if (!Line.empty())
96 CHRFunctions.insert(Line);
97 }
98 }
99}
100
101namespace {
102class ControlHeightReductionLegacyPass : public FunctionPass {
103public:
104 static char ID;
105
106 ControlHeightReductionLegacyPass() : FunctionPass(ID) {
107 initializeControlHeightReductionLegacyPassPass(
108 *PassRegistry::getPassRegistry());
109 parseCHRFilterFiles();
110 }
111
112 bool runOnFunction(Function &F) override;
113 void getAnalysisUsage(AnalysisUsage &AU) const override {
114 AU.addRequired<BlockFrequencyInfoWrapperPass>();
115 AU.addRequired<DominatorTreeWrapperPass>();
116 AU.addRequired<ProfileSummaryInfoWrapperPass>();
117 AU.addRequired<RegionInfoPass>();
118 AU.addPreserved<GlobalsAAWrapperPass>();
119 }
120};
121} // end anonymous namespace
122
123char ControlHeightReductionLegacyPass::ID = 0;
124
125INITIALIZE_PASS_BEGIN(ControlHeightReductionLegacyPass,static void *initializeControlHeightReductionLegacyPassPassOnce
(PassRegistry &Registry) {
126 "chr",static void *initializeControlHeightReductionLegacyPassPassOnce
(PassRegistry &Registry) {
127 "Reduce control height in the hot paths",static void *initializeControlHeightReductionLegacyPassPassOnce
(PassRegistry &Registry) {
128 false, false)static void *initializeControlHeightReductionLegacyPassPassOnce
(PassRegistry &Registry) {
129INITIALIZE_PASS_DEPENDENCY(BlockFrequencyInfoWrapperPass)initializeBlockFrequencyInfoWrapperPassPass(Registry);
130INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)initializeDominatorTreeWrapperPassPass(Registry);
131INITIALIZE_PASS_DEPENDENCY(ProfileSummaryInfoWrapperPass)initializeProfileSummaryInfoWrapperPassPass(Registry);
132INITIALIZE_PASS_DEPENDENCY(RegionInfoPass)initializeRegionInfoPassPass(Registry);
133INITIALIZE_PASS_END(ControlHeightReductionLegacyPass,PassInfo *PI = new PassInfo( "Reduce control height in the hot paths"
, "chr", &ControlHeightReductionLegacyPass::ID, PassInfo::
NormalCtor_t(callDefaultCtor<ControlHeightReductionLegacyPass
>), false, false); Registry.registerPass(*PI, true); return
PI; } static llvm::once_flag InitializeControlHeightReductionLegacyPassPassFlag
; void llvm::initializeControlHeightReductionLegacyPassPass(PassRegistry
&Registry) { llvm::call_once(InitializeControlHeightReductionLegacyPassPassFlag
, initializeControlHeightReductionLegacyPassPassOnce, std::ref
(Registry)); }
134 "chr",PassInfo *PI = new PassInfo( "Reduce control height in the hot paths"
, "chr", &ControlHeightReductionLegacyPass::ID, PassInfo::
NormalCtor_t(callDefaultCtor<ControlHeightReductionLegacyPass
>), false, false); Registry.registerPass(*PI, true); return
PI; } static llvm::once_flag InitializeControlHeightReductionLegacyPassPassFlag
; void llvm::initializeControlHeightReductionLegacyPassPass(PassRegistry
&Registry) { llvm::call_once(InitializeControlHeightReductionLegacyPassPassFlag
, initializeControlHeightReductionLegacyPassPassOnce, std::ref
(Registry)); }
135 "Reduce control height in the hot paths",PassInfo *PI = new PassInfo( "Reduce control height in the hot paths"
, "chr", &ControlHeightReductionLegacyPass::ID, PassInfo::
NormalCtor_t(callDefaultCtor<ControlHeightReductionLegacyPass
>), false, false); Registry.registerPass(*PI, true); return
PI; } static llvm::once_flag InitializeControlHeightReductionLegacyPassPassFlag
; void llvm::initializeControlHeightReductionLegacyPassPass(PassRegistry
&Registry) { llvm::call_once(InitializeControlHeightReductionLegacyPassPassFlag
, initializeControlHeightReductionLegacyPassPassOnce, std::ref
(Registry)); }
136 false, false)PassInfo *PI = new PassInfo( "Reduce control height in the hot paths"
, "chr", &ControlHeightReductionLegacyPass::ID, PassInfo::
NormalCtor_t(callDefaultCtor<ControlHeightReductionLegacyPass
>), false, false); Registry.registerPass(*PI, true); return
PI; } static llvm::once_flag InitializeControlHeightReductionLegacyPassPassFlag
; void llvm::initializeControlHeightReductionLegacyPassPass(PassRegistry
&Registry) { llvm::call_once(InitializeControlHeightReductionLegacyPassPassFlag
, initializeControlHeightReductionLegacyPassPassOnce, std::ref
(Registry)); }
137
138FunctionPass *llvm::createControlHeightReductionLegacyPass() {
139 return new ControlHeightReductionLegacyPass();
140}
141
142namespace {
143
144struct CHRStats {
145 CHRStats() : NumBranches(0), NumBranchesDelta(0),
146 WeightedNumBranchesDelta(0) {}
147 void print(raw_ostream &OS) const {
148 OS << "CHRStats: NumBranches " << NumBranches
149 << " NumBranchesDelta " << NumBranchesDelta
150 << " WeightedNumBranchesDelta " << WeightedNumBranchesDelta;
151 }
152 uint64_t NumBranches; // The original number of conditional branches /
153 // selects
154 uint64_t NumBranchesDelta; // The decrease of the number of conditional
155 // branches / selects in the hot paths due to CHR.
156 uint64_t WeightedNumBranchesDelta; // NumBranchesDelta weighted by the profile
157 // count at the scope entry.
158};
159
160// RegInfo - some properties of a Region.
161struct RegInfo {
162 RegInfo() : R(nullptr), HasBranch(false) {}
163 RegInfo(Region *RegionIn) : R(RegionIn), HasBranch(false) {}
164 Region *R;
165 bool HasBranch;
166 SmallVector<SelectInst *, 8> Selects;
167};
168
169typedef DenseMap<Region *, DenseSet<Instruction *>> HoistStopMapTy;
170
171// CHRScope - a sequence of regions to CHR together. It corresponds to a
172// sequence of conditional blocks. It can have subscopes which correspond to
173// nested conditional blocks. Nested CHRScopes form a tree.
174class CHRScope {
175 public:
176 CHRScope(RegInfo RI) : BranchInsertPoint(nullptr) {
177 assert(RI.R && "Null RegionIn")((RI.R && "Null RegionIn") ? static_cast<void> (
0) : __assert_fail ("RI.R && \"Null RegionIn\"", "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 177, __PRETTY_FUNCTION__))
;
178 RegInfos.push_back(RI);
179 }
180
181 Region *getParentRegion() {
182 assert(RegInfos.size() > 0 && "Empty CHRScope")((RegInfos.size() > 0 && "Empty CHRScope") ? static_cast
<void> (0) : __assert_fail ("RegInfos.size() > 0 && \"Empty CHRScope\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 182, __PRETTY_FUNCTION__))
;
183 Region *Parent = RegInfos[0].R->getParent();
184 assert(Parent && "Unexpected to call this on the top-level region")((Parent && "Unexpected to call this on the top-level region"
) ? static_cast<void> (0) : __assert_fail ("Parent && \"Unexpected to call this on the top-level region\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 184, __PRETTY_FUNCTION__))
;
185 return Parent;
186 }
187
188 BasicBlock *getEntryBlock() {
189 assert(RegInfos.size() > 0 && "Empty CHRScope")((RegInfos.size() > 0 && "Empty CHRScope") ? static_cast
<void> (0) : __assert_fail ("RegInfos.size() > 0 && \"Empty CHRScope\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 189, __PRETTY_FUNCTION__))
;
190 return RegInfos.front().R->getEntry();
191 }
192
193 BasicBlock *getExitBlock() {
194 assert(RegInfos.size() > 0 && "Empty CHRScope")((RegInfos.size() > 0 && "Empty CHRScope") ? static_cast
<void> (0) : __assert_fail ("RegInfos.size() > 0 && \"Empty CHRScope\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 194, __PRETTY_FUNCTION__))
;
195 return RegInfos.back().R->getExit();
196 }
197
198 bool appendable(CHRScope *Next) {
199 // The next scope is appendable only if this scope is directly connected to
200 // it (which implies it post-dominates this scope) and this scope dominates
201 // it (no edge to the next scope outside this scope).
202 BasicBlock *NextEntry = Next->getEntryBlock();
203 if (getExitBlock() != NextEntry)
204 // Not directly connected.
205 return false;
206 Region *LastRegion = RegInfos.back().R;
207 for (BasicBlock *Pred : predecessors(NextEntry))
208 if (!LastRegion->contains(Pred))
209 // There's an edge going into the entry of the next scope from outside
210 // of this scope.
211 return false;
212 return true;
213 }
214
215 void append(CHRScope *Next) {
216 assert(RegInfos.size() > 0 && "Empty CHRScope")((RegInfos.size() > 0 && "Empty CHRScope") ? static_cast
<void> (0) : __assert_fail ("RegInfos.size() > 0 && \"Empty CHRScope\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 216, __PRETTY_FUNCTION__))
;
217 assert(Next->RegInfos.size() > 0 && "Empty CHRScope")((Next->RegInfos.size() > 0 && "Empty CHRScope"
) ? static_cast<void> (0) : __assert_fail ("Next->RegInfos.size() > 0 && \"Empty CHRScope\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 217, __PRETTY_FUNCTION__))
;
218 assert(getParentRegion() == Next->getParentRegion() &&((getParentRegion() == Next->getParentRegion() && "Must be siblings"
) ? static_cast<void> (0) : __assert_fail ("getParentRegion() == Next->getParentRegion() && \"Must be siblings\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 219, __PRETTY_FUNCTION__))
219 "Must be siblings")((getParentRegion() == Next->getParentRegion() && "Must be siblings"
) ? static_cast<void> (0) : __assert_fail ("getParentRegion() == Next->getParentRegion() && \"Must be siblings\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 219, __PRETTY_FUNCTION__))
;
220 assert(getExitBlock() == Next->getEntryBlock() &&((getExitBlock() == Next->getEntryBlock() && "Must be adjacent"
) ? static_cast<void> (0) : __assert_fail ("getExitBlock() == Next->getEntryBlock() && \"Must be adjacent\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 221, __PRETTY_FUNCTION__))
221 "Must be adjacent")((getExitBlock() == Next->getEntryBlock() && "Must be adjacent"
) ? static_cast<void> (0) : __assert_fail ("getExitBlock() == Next->getEntryBlock() && \"Must be adjacent\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 221, __PRETTY_FUNCTION__))
;
222 for (RegInfo &RI : Next->RegInfos)
223 RegInfos.push_back(RI);
224 for (CHRScope *Sub : Next->Subs)
225 Subs.push_back(Sub);
226 }
227
228 void addSub(CHRScope *SubIn) {
229#ifndef NDEBUG
230 bool IsChild = false;
231 for (RegInfo &RI : RegInfos)
232 if (RI.R == SubIn->getParentRegion()) {
233 IsChild = true;
234 break;
235 }
236 assert(IsChild && "Must be a child")((IsChild && "Must be a child") ? static_cast<void
> (0) : __assert_fail ("IsChild && \"Must be a child\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 236, __PRETTY_FUNCTION__))
;
237#endif
238 Subs.push_back(SubIn);
239 }
240
241 // Split this scope at the boundary region into two, which will belong to the
242 // tail and returns the tail.
243 CHRScope *split(Region *Boundary) {
244 assert(Boundary && "Boundary null")((Boundary && "Boundary null") ? static_cast<void>
(0) : __assert_fail ("Boundary && \"Boundary null\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 244, __PRETTY_FUNCTION__))
;
245 assert(RegInfos.begin()->R != Boundary &&((RegInfos.begin()->R != Boundary && "Can't be split at beginning"
) ? static_cast<void> (0) : __assert_fail ("RegInfos.begin()->R != Boundary && \"Can't be split at beginning\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 246, __PRETTY_FUNCTION__))
246 "Can't be split at beginning")((RegInfos.begin()->R != Boundary && "Can't be split at beginning"
) ? static_cast<void> (0) : __assert_fail ("RegInfos.begin()->R != Boundary && \"Can't be split at beginning\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 246, __PRETTY_FUNCTION__))
;
247 auto BoundaryIt = std::find_if(RegInfos.begin(), RegInfos.end(),
248 [&Boundary](const RegInfo& RI) {
249 return Boundary == RI.R;
250 });
251 if (BoundaryIt == RegInfos.end())
252 return nullptr;
253 SmallVector<RegInfo, 8> TailRegInfos;
254 SmallVector<CHRScope *, 8> TailSubs;
255 TailRegInfos.insert(TailRegInfos.begin(), BoundaryIt, RegInfos.end());
256 RegInfos.resize(BoundaryIt - RegInfos.begin());
257 DenseSet<Region *> TailRegionSet;
258 for (RegInfo &RI : TailRegInfos)
259 TailRegionSet.insert(RI.R);
260 for (auto It = Subs.begin(); It != Subs.end(); ) {
261 CHRScope *Sub = *It;
262 assert(Sub && "null Sub")((Sub && "null Sub") ? static_cast<void> (0) : __assert_fail
("Sub && \"null Sub\"", "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 262, __PRETTY_FUNCTION__))
;
263 Region *Parent = Sub->getParentRegion();
264 if (TailRegionSet.count(Parent)) {
265 TailSubs.push_back(Sub);
266 It = Subs.erase(It);
267 } else {
268 assert(std::find_if(RegInfos.begin(), RegInfos.end(),((std::find_if(RegInfos.begin(), RegInfos.end(), [&Parent
](const RegInfo& RI) { return Parent == RI.R; }) != RegInfos
.end() && "Must be in head") ? static_cast<void>
(0) : __assert_fail ("std::find_if(RegInfos.begin(), RegInfos.end(), [&Parent](const RegInfo& RI) { return Parent == RI.R; }) != RegInfos.end() && \"Must be in head\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 272, __PRETTY_FUNCTION__))
269 [&Parent](const RegInfo& RI) {((std::find_if(RegInfos.begin(), RegInfos.end(), [&Parent
](const RegInfo& RI) { return Parent == RI.R; }) != RegInfos
.end() && "Must be in head") ? static_cast<void>
(0) : __assert_fail ("std::find_if(RegInfos.begin(), RegInfos.end(), [&Parent](const RegInfo& RI) { return Parent == RI.R; }) != RegInfos.end() && \"Must be in head\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 272, __PRETTY_FUNCTION__))
270 return Parent == RI.R;((std::find_if(RegInfos.begin(), RegInfos.end(), [&Parent
](const RegInfo& RI) { return Parent == RI.R; }) != RegInfos
.end() && "Must be in head") ? static_cast<void>
(0) : __assert_fail ("std::find_if(RegInfos.begin(), RegInfos.end(), [&Parent](const RegInfo& RI) { return Parent == RI.R; }) != RegInfos.end() && \"Must be in head\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 272, __PRETTY_FUNCTION__))
271 }) != RegInfos.end() &&((std::find_if(RegInfos.begin(), RegInfos.end(), [&Parent
](const RegInfo& RI) { return Parent == RI.R; }) != RegInfos
.end() && "Must be in head") ? static_cast<void>
(0) : __assert_fail ("std::find_if(RegInfos.begin(), RegInfos.end(), [&Parent](const RegInfo& RI) { return Parent == RI.R; }) != RegInfos.end() && \"Must be in head\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 272, __PRETTY_FUNCTION__))
272 "Must be in head")((std::find_if(RegInfos.begin(), RegInfos.end(), [&Parent
](const RegInfo& RI) { return Parent == RI.R; }) != RegInfos
.end() && "Must be in head") ? static_cast<void>
(0) : __assert_fail ("std::find_if(RegInfos.begin(), RegInfos.end(), [&Parent](const RegInfo& RI) { return Parent == RI.R; }) != RegInfos.end() && \"Must be in head\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 272, __PRETTY_FUNCTION__))
;
273 ++It;
274 }
275 }
276 assert(HoistStopMap.empty() && "MapHoistStops must be empty")((HoistStopMap.empty() && "MapHoistStops must be empty"
) ? static_cast<void> (0) : __assert_fail ("HoistStopMap.empty() && \"MapHoistStops must be empty\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 276, __PRETTY_FUNCTION__))
;
277 return new CHRScope(TailRegInfos, TailSubs);
278 }
279
280 bool contains(Instruction *I) const {
281 BasicBlock *Parent = I->getParent();
282 for (const RegInfo &RI : RegInfos)
283 if (RI.R->contains(Parent))
284 return true;
285 return false;
286 }
287
288 void print(raw_ostream &OS) const;
289
290 SmallVector<RegInfo, 8> RegInfos; // Regions that belong to this scope
291 SmallVector<CHRScope *, 8> Subs; // Subscopes.
292
293 // The instruction at which to insert the CHR conditional branch (and hoist
294 // the dependent condition values).
295 Instruction *BranchInsertPoint;
296
297 // True-biased and false-biased regions (conditional blocks),
298 // respectively. Used only for the outermost scope and includes regions in
299 // subscopes. The rest are unbiased.
300 DenseSet<Region *> TrueBiasedRegions;
301 DenseSet<Region *> FalseBiasedRegions;
302 // Among the biased regions, the regions that get CHRed.
303 SmallVector<RegInfo, 8> CHRRegions;
304
305 // True-biased and false-biased selects, respectively. Used only for the
306 // outermost scope and includes ones in subscopes.
307 DenseSet<SelectInst *> TrueBiasedSelects;
308 DenseSet<SelectInst *> FalseBiasedSelects;
309
310 // Map from one of the above regions to the instructions to stop
311 // hoisting instructions at through use-def chains.
312 HoistStopMapTy HoistStopMap;
313
314 private:
315 CHRScope(SmallVector<RegInfo, 8> &RegInfosIn,
316 SmallVector<CHRScope *, 8> &SubsIn)
317 : RegInfos(RegInfosIn), Subs(SubsIn), BranchInsertPoint(nullptr) {}
318};
319
320class CHR {
321 public:
322 CHR(Function &Fin, BlockFrequencyInfo &BFIin, DominatorTree &DTin,
323 ProfileSummaryInfo &PSIin, RegionInfo &RIin,
324 OptimizationRemarkEmitter &OREin)
325 : F(Fin), BFI(BFIin), DT(DTin), PSI(PSIin), RI(RIin), ORE(OREin) {}
326
327 ~CHR() {
328 for (CHRScope *Scope : Scopes) {
329 delete Scope;
330 }
331 }
332
333 bool run();
334
335 private:
336 // See the comments in CHR::run() for the high level flow of the algorithm and
337 // what the following functions do.
338
339 void findScopes(SmallVectorImpl<CHRScope *> &Output) {
340 Region *R = RI.getTopLevelRegion();
341 CHRScope *Scope = findScopes(R, nullptr, nullptr, Output);
342 if (Scope) {
343 Output.push_back(Scope);
344 }
345 }
346 CHRScope *findScopes(Region *R, Region *NextRegion, Region *ParentRegion,
347 SmallVectorImpl<CHRScope *> &Scopes);
348 CHRScope *findScope(Region *R);
349 void checkScopeHoistable(CHRScope *Scope);
350
351 void splitScopes(SmallVectorImpl<CHRScope *> &Input,
352 SmallVectorImpl<CHRScope *> &Output);
353 SmallVector<CHRScope *, 8> splitScope(CHRScope *Scope,
354 CHRScope *Outer,
355 DenseSet<Value *> *OuterConditionValues,
356 Instruction *OuterInsertPoint,
357 SmallVectorImpl<CHRScope *> &Output,
358 DenseSet<Instruction *> &Unhoistables);
359
360 void classifyBiasedScopes(SmallVectorImpl<CHRScope *> &Scopes);
361 void classifyBiasedScopes(CHRScope *Scope, CHRScope *OutermostScope);
362
363 void filterScopes(SmallVectorImpl<CHRScope *> &Input,
364 SmallVectorImpl<CHRScope *> &Output);
365
366 void setCHRRegions(SmallVectorImpl<CHRScope *> &Input,
367 SmallVectorImpl<CHRScope *> &Output);
368 void setCHRRegions(CHRScope *Scope, CHRScope *OutermostScope);
369
370 void sortScopes(SmallVectorImpl<CHRScope *> &Input,
371 SmallVectorImpl<CHRScope *> &Output);
372
373 void transformScopes(SmallVectorImpl<CHRScope *> &CHRScopes);
374 void transformScopes(CHRScope *Scope, DenseSet<PHINode *> &TrivialPHIs);
375 void cloneScopeBlocks(CHRScope *Scope,
376 BasicBlock *PreEntryBlock,
377 BasicBlock *ExitBlock,
378 Region *LastRegion,
379 ValueToValueMapTy &VMap);
380 BranchInst *createMergedBranch(BasicBlock *PreEntryBlock,
381 BasicBlock *EntryBlock,
382 BasicBlock *NewEntryBlock,
383 ValueToValueMapTy &VMap);
384 void fixupBranchesAndSelects(CHRScope *Scope,
385 BasicBlock *PreEntryBlock,
386 BranchInst *MergedBR,
387 uint64_t ProfileCount);
388 void fixupBranch(Region *R,
389 CHRScope *Scope,
390 IRBuilder<> &IRB,
391 Value *&MergedCondition, BranchProbability &CHRBranchBias);
392 void fixupSelect(SelectInst* SI,
393 CHRScope *Scope,
394 IRBuilder<> &IRB,
395 Value *&MergedCondition, BranchProbability &CHRBranchBias);
396 void addToMergedCondition(bool IsTrueBiased, Value *Cond,
397 Instruction *BranchOrSelect,
398 CHRScope *Scope,
399 IRBuilder<> &IRB,
400 Value *&MergedCondition);
401
402 Function &F;
403 BlockFrequencyInfo &BFI;
404 DominatorTree &DT;
405 ProfileSummaryInfo &PSI;
406 RegionInfo &RI;
407 OptimizationRemarkEmitter &ORE;
408 CHRStats Stats;
409
410 // All the true-biased regions in the function
411 DenseSet<Region *> TrueBiasedRegionsGlobal;
412 // All the false-biased regions in the function
413 DenseSet<Region *> FalseBiasedRegionsGlobal;
414 // All the true-biased selects in the function
415 DenseSet<SelectInst *> TrueBiasedSelectsGlobal;
416 // All the false-biased selects in the function
417 DenseSet<SelectInst *> FalseBiasedSelectsGlobal;
418 // A map from biased regions to their branch bias
419 DenseMap<Region *, BranchProbability> BranchBiasMap;
420 // A map from biased selects to their branch bias
421 DenseMap<SelectInst *, BranchProbability> SelectBiasMap;
422 // All the scopes.
423 DenseSet<CHRScope *> Scopes;
424};
425
426} // end anonymous namespace
427
428static inline
429raw_ostream LLVM_ATTRIBUTE_UNUSED__attribute__((__unused__)) &operator<<(raw_ostream &OS,
430 const CHRStats &Stats) {
431 Stats.print(OS);
432 return OS;
433}
434
435static inline
436raw_ostream &operator<<(raw_ostream &OS, const CHRScope &Scope) {
437 Scope.print(OS);
438 return OS;
439}
440
441static bool shouldApply(Function &F, ProfileSummaryInfo& PSI) {
442 if (ForceCHR)
443 return true;
444
445 if (!CHRModuleList.empty() || !CHRFunctionList.empty()) {
446 if (CHRModules.count(F.getParent()->getName()))
447 return true;
448 return CHRFunctions.count(F.getName());
449 }
450
451 assert(PSI.hasProfileSummary() && "Empty PSI?")((PSI.hasProfileSummary() && "Empty PSI?") ? static_cast
<void> (0) : __assert_fail ("PSI.hasProfileSummary() && \"Empty PSI?\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 451, __PRETTY_FUNCTION__))
;
452 return PSI.isFunctionEntryHot(&F);
453}
454
455static void LLVM_ATTRIBUTE_UNUSED__attribute__((__unused__)) dumpIR(Function &F, const char *Label,
456 CHRStats *Stats) {
457 StringRef FuncName = F.getName();
458 StringRef ModuleName = F.getParent()->getName();
459 (void)(FuncName); // Unused in release build.
460 (void)(ModuleName); // Unused in release build.
461 CHR_DEBUG(dbgs() << "CHR IR dump " << Label << " " << ModuleName << " "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "CHR IR dump " << Label <<
" " << ModuleName << " " << FuncName; } } while
(false)
462 << FuncName)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "CHR IR dump " << Label <<
" " << ModuleName << " " << FuncName; } } while
(false)
;
463 if (Stats)
464 CHR_DEBUG(dbgs() << " " << *Stats)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << " " << *Stats; } } while (false
)
;
465 CHR_DEBUG(dbgs() << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "\n"; } } while (false)
;
466 CHR_DEBUG(F.dump())do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { F.dump(); } } while (false)
;
467}
468
469void CHRScope::print(raw_ostream &OS) const {
470 assert(RegInfos.size() > 0 && "Empty CHRScope")((RegInfos.size() > 0 && "Empty CHRScope") ? static_cast
<void> (0) : __assert_fail ("RegInfos.size() > 0 && \"Empty CHRScope\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 470, __PRETTY_FUNCTION__))
;
471 OS << "CHRScope[";
472 OS << RegInfos.size() << ", Regions[";
473 for (const RegInfo &RI : RegInfos) {
474 OS << RI.R->getNameStr();
475 if (RI.HasBranch)
476 OS << " B";
477 if (RI.Selects.size() > 0)
478 OS << " S" << RI.Selects.size();
479 OS << ", ";
480 }
481 if (RegInfos[0].R->getParent()) {
482 OS << "], Parent " << RegInfos[0].R->getParent()->getNameStr();
483 } else {
484 // top level region
485 OS << "]";
486 }
487 OS << ", Subs[";
488 for (CHRScope *Sub : Subs) {
489 OS << *Sub << ", ";
490 }
491 OS << "]]";
492}
493
494// Return true if the given instruction type can be hoisted by CHR.
495static bool isHoistableInstructionType(Instruction *I) {
496 return isa<BinaryOperator>(I) || isa<CastInst>(I) || isa<SelectInst>(I) ||
497 isa<GetElementPtrInst>(I) || isa<CmpInst>(I) ||
498 isa<InsertElementInst>(I) || isa<ExtractElementInst>(I) ||
499 isa<ShuffleVectorInst>(I) || isa<ExtractValueInst>(I) ||
500 isa<InsertValueInst>(I);
501}
502
503// Return true if the given instruction can be hoisted by CHR.
504static bool isHoistable(Instruction *I, DominatorTree &DT) {
505 if (!isHoistableInstructionType(I))
506 return false;
507 return isSafeToSpeculativelyExecute(I, nullptr, &DT);
508}
509
510// Recursively traverse the use-def chains of the given value and return a set
511// of the unhoistable base values defined within the scope (excluding the
512// first-region entry block) or the (hoistable or unhoistable) base values that
513// are defined outside (including the first-region entry block) of the
514// scope. The returned set doesn't include constants.
515static std::set<Value *> getBaseValues(
516 Value *V, DominatorTree &DT,
517 DenseMap<Value *, std::set<Value *>> &Visited) {
518 if (Visited.count(V)) {
519 return Visited[V];
520 }
521 std::set<Value *> Result;
522 if (auto *I = dyn_cast<Instruction>(V)) {
523 // We don't stop at a block that's not in the Scope because we would miss some
524 // instructions that are based on the same base values if we stop there.
525 if (!isHoistable(I, DT)) {
526 Result.insert(I);
527 Visited.insert(std::make_pair(V, Result));
528 return Result;
529 }
530 // I is hoistable above the Scope.
531 for (Value *Op : I->operands()) {
532 std::set<Value *> OpResult = getBaseValues(Op, DT, Visited);
533 Result.insert(OpResult.begin(), OpResult.end());
534 }
535 Visited.insert(std::make_pair(V, Result));
536 return Result;
537 }
538 if (isa<Argument>(V)) {
539 Result.insert(V);
540 Visited.insert(std::make_pair(V, Result));
541 return Result;
542 }
543 // We don't include others like constants because those won't lead to any
544 // chance of folding of conditions (eg two bit checks merged into one check)
545 // after CHR.
546 Visited.insert(std::make_pair(V, Result));
547 return Result; // empty
548}
549
550// Return true if V is already hoisted or can be hoisted (along with its
551// operands) above the insert point. When it returns true and HoistStops is
552// non-null, the instructions to stop hoisting at through the use-def chains are
553// inserted into HoistStops.
554static bool
555checkHoistValue(Value *V, Instruction *InsertPoint, DominatorTree &DT,
556 DenseSet<Instruction *> &Unhoistables,
557 DenseSet<Instruction *> *HoistStops,
558 DenseMap<Instruction *, bool> &Visited) {
559 assert(InsertPoint && "Null InsertPoint")((InsertPoint && "Null InsertPoint") ? static_cast<
void> (0) : __assert_fail ("InsertPoint && \"Null InsertPoint\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 559, __PRETTY_FUNCTION__))
;
560 if (auto *I = dyn_cast<Instruction>(V)) {
561 if (Visited.count(I)) {
562 return Visited[I];
563 }
564 assert(DT.getNode(I->getParent()) && "DT must contain I's parent block")((DT.getNode(I->getParent()) && "DT must contain I's parent block"
) ? static_cast<void> (0) : __assert_fail ("DT.getNode(I->getParent()) && \"DT must contain I's parent block\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 564, __PRETTY_FUNCTION__))
;
565 assert(DT.getNode(InsertPoint->getParent()) && "DT must contain Destination")((DT.getNode(InsertPoint->getParent()) && "DT must contain Destination"
) ? static_cast<void> (0) : __assert_fail ("DT.getNode(InsertPoint->getParent()) && \"DT must contain Destination\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 565, __PRETTY_FUNCTION__))
;
566 if (Unhoistables.count(I)) {
567 // Don't hoist if they are not to be hoisted.
568 Visited[I] = false;
569 return false;
570 }
571 if (DT.dominates(I, InsertPoint)) {
572 // We are already above the insert point. Stop here.
573 if (HoistStops)
574 HoistStops->insert(I);
575 Visited[I] = true;
576 return true;
577 }
578 // We aren't not above the insert point, check if we can hoist it above the
579 // insert point.
580 if (isHoistable(I, DT)) {
581 // Check operands first.
582 DenseSet<Instruction *> OpsHoistStops;
583 bool AllOpsHoisted = true;
584 for (Value *Op : I->operands()) {
585 if (!checkHoistValue(Op, InsertPoint, DT, Unhoistables, &OpsHoistStops,
586 Visited)) {
587 AllOpsHoisted = false;
588 break;
589 }
590 }
591 if (AllOpsHoisted) {
592 CHR_DEBUG(dbgs() << "checkHoistValue " << *I << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "checkHoistValue " << *I <<
"\n"; } } while (false)
;
593 if (HoistStops)
594 HoistStops->insert(OpsHoistStops.begin(), OpsHoistStops.end());
595 Visited[I] = true;
596 return true;
597 }
598 }
599 Visited[I] = false;
600 return false;
601 }
602 // Non-instructions are considered hoistable.
603 return true;
604}
605
606// Returns true and sets the true probability and false probability of an
607// MD_prof metadata if it's well-formed.
608static bool checkMDProf(MDNode *MD, BranchProbability &TrueProb,
609 BranchProbability &FalseProb) {
610 if (!MD) return false;
611 MDString *MDName = cast<MDString>(MD->getOperand(0));
612 if (MDName->getString() != "branch_weights" ||
613 MD->getNumOperands() != 3)
614 return false;
615 ConstantInt *TrueWeight = mdconst::extract<ConstantInt>(MD->getOperand(1));
616 ConstantInt *FalseWeight = mdconst::extract<ConstantInt>(MD->getOperand(2));
617 if (!TrueWeight || !FalseWeight)
618 return false;
619 uint64_t TrueWt = TrueWeight->getValue().getZExtValue();
620 uint64_t FalseWt = FalseWeight->getValue().getZExtValue();
621 uint64_t SumWt = TrueWt + FalseWt;
622
623 assert(SumWt >= TrueWt && SumWt >= FalseWt &&((SumWt >= TrueWt && SumWt >= FalseWt &&
"Overflow calculating branch probabilities.") ? static_cast<
void> (0) : __assert_fail ("SumWt >= TrueWt && SumWt >= FalseWt && \"Overflow calculating branch probabilities.\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 624, __PRETTY_FUNCTION__))
624 "Overflow calculating branch probabilities.")((SumWt >= TrueWt && SumWt >= FalseWt &&
"Overflow calculating branch probabilities.") ? static_cast<
void> (0) : __assert_fail ("SumWt >= TrueWt && SumWt >= FalseWt && \"Overflow calculating branch probabilities.\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 624, __PRETTY_FUNCTION__))
;
625
626 TrueProb = BranchProbability::getBranchProbability(TrueWt, SumWt);
627 FalseProb = BranchProbability::getBranchProbability(FalseWt, SumWt);
628 return true;
629}
630
631static BranchProbability getCHRBiasThreshold() {
632 return BranchProbability::getBranchProbability(
633 static_cast<uint64_t>(CHRBiasThreshold * 1000000), 1000000);
634}
635
636// A helper for CheckBiasedBranch and CheckBiasedSelect. If TrueProb >=
637// CHRBiasThreshold, put Key into TrueSet and return true. If FalseProb >=
638// CHRBiasThreshold, put Key into FalseSet and return true. Otherwise, return
639// false.
640template <typename K, typename S, typename M>
641static bool checkBias(K *Key, BranchProbability TrueProb,
642 BranchProbability FalseProb, S &TrueSet, S &FalseSet,
643 M &BiasMap) {
644 BranchProbability Threshold = getCHRBiasThreshold();
645 if (TrueProb >= Threshold) {
646 TrueSet.insert(Key);
647 BiasMap[Key] = TrueProb;
648 return true;
649 } else if (FalseProb >= Threshold) {
650 FalseSet.insert(Key);
651 BiasMap[Key] = FalseProb;
652 return true;
653 }
654 return false;
655}
656
657// Returns true and insert a region into the right biased set and the map if the
658// branch of the region is biased.
659static bool checkBiasedBranch(BranchInst *BI, Region *R,
660 DenseSet<Region *> &TrueBiasedRegionsGlobal,
661 DenseSet<Region *> &FalseBiasedRegionsGlobal,
662 DenseMap<Region *, BranchProbability> &BranchBiasMap) {
663 if (!BI->isConditional())
664 return false;
665 BranchProbability ThenProb, ElseProb;
666 if (!checkMDProf(BI->getMetadata(LLVMContext::MD_prof),
667 ThenProb, ElseProb))
668 return false;
669 BasicBlock *IfThen = BI->getSuccessor(0);
670 BasicBlock *IfElse = BI->getSuccessor(1);
671 assert((IfThen == R->getExit() || IfElse == R->getExit()) &&(((IfThen == R->getExit() || IfElse == R->getExit()) &&
IfThen != IfElse && "Invariant from findScopes") ? static_cast
<void> (0) : __assert_fail ("(IfThen == R->getExit() || IfElse == R->getExit()) && IfThen != IfElse && \"Invariant from findScopes\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 673, __PRETTY_FUNCTION__))
672 IfThen != IfElse &&(((IfThen == R->getExit() || IfElse == R->getExit()) &&
IfThen != IfElse && "Invariant from findScopes") ? static_cast
<void> (0) : __assert_fail ("(IfThen == R->getExit() || IfElse == R->getExit()) && IfThen != IfElse && \"Invariant from findScopes\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 673, __PRETTY_FUNCTION__))
673 "Invariant from findScopes")(((IfThen == R->getExit() || IfElse == R->getExit()) &&
IfThen != IfElse && "Invariant from findScopes") ? static_cast
<void> (0) : __assert_fail ("(IfThen == R->getExit() || IfElse == R->getExit()) && IfThen != IfElse && \"Invariant from findScopes\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 673, __PRETTY_FUNCTION__))
;
674 if (IfThen == R->getExit()) {
675 // Swap them so that IfThen/ThenProb means going into the conditional code
676 // and IfElse/ElseProb means skipping it.
677 std::swap(IfThen, IfElse);
678 std::swap(ThenProb, ElseProb);
679 }
680 CHR_DEBUG(dbgs() << "BI " << *BI << " ")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "BI " << *BI << " "; }
} while (false)
;
681 CHR_DEBUG(dbgs() << "ThenProb " << ThenProb << " ")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "ThenProb " << ThenProb <<
" "; } } while (false)
;
682 CHR_DEBUG(dbgs() << "ElseProb " << ElseProb << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "ElseProb " << ElseProb <<
"\n"; } } while (false)
;
683 return checkBias(R, ThenProb, ElseProb,
684 TrueBiasedRegionsGlobal, FalseBiasedRegionsGlobal,
685 BranchBiasMap);
686}
687
688// Returns true and insert a select into the right biased set and the map if the
689// select is biased.
690static bool checkBiasedSelect(
691 SelectInst *SI, Region *R,
692 DenseSet<SelectInst *> &TrueBiasedSelectsGlobal,
693 DenseSet<SelectInst *> &FalseBiasedSelectsGlobal,
694 DenseMap<SelectInst *, BranchProbability> &SelectBiasMap) {
695 BranchProbability TrueProb, FalseProb;
696 if (!checkMDProf(SI->getMetadata(LLVMContext::MD_prof),
697 TrueProb, FalseProb))
698 return false;
699 CHR_DEBUG(dbgs() << "SI " << *SI << " ")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "SI " << *SI << " "; }
} while (false)
;
700 CHR_DEBUG(dbgs() << "TrueProb " << TrueProb << " ")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "TrueProb " << TrueProb <<
" "; } } while (false)
;
701 CHR_DEBUG(dbgs() << "FalseProb " << FalseProb << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "FalseProb " << FalseProb <<
"\n"; } } while (false)
;
702 return checkBias(SI, TrueProb, FalseProb,
703 TrueBiasedSelectsGlobal, FalseBiasedSelectsGlobal,
704 SelectBiasMap);
705}
706
707// Returns the instruction at which to hoist the dependent condition values and
708// insert the CHR branch for a region. This is the terminator branch in the
709// entry block or the first select in the entry block, if any.
710static Instruction* getBranchInsertPoint(RegInfo &RI) {
711 Region *R = RI.R;
712 BasicBlock *EntryBB = R->getEntry();
713 // The hoist point is by default the terminator of the entry block, which is
714 // the same as the branch instruction if RI.HasBranch is true.
715 Instruction *HoistPoint = EntryBB->getTerminator();
716 for (SelectInst *SI : RI.Selects) {
717 if (SI->getParent() == EntryBB) {
718 // Pick the first select in Selects in the entry block. Note Selects is
719 // sorted in the instruction order within a block (asserted below).
720 HoistPoint = SI;
721 break;
722 }
723 }
724 assert(HoistPoint && "Null HoistPoint")((HoistPoint && "Null HoistPoint") ? static_cast<void
> (0) : __assert_fail ("HoistPoint && \"Null HoistPoint\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 724, __PRETTY_FUNCTION__))
;
725#ifndef NDEBUG
726 // Check that HoistPoint is the first one in Selects in the entry block,
727 // if any.
728 DenseSet<Instruction *> EntryBlockSelectSet;
729 for (SelectInst *SI : RI.Selects) {
730 if (SI->getParent() == EntryBB) {
731 EntryBlockSelectSet.insert(SI);
732 }
733 }
734 for (Instruction &I : *EntryBB) {
735 if (EntryBlockSelectSet.count(&I) > 0) {
736 assert(&I == HoistPoint &&((&I == HoistPoint && "HoistPoint must be the first one in Selects"
) ? static_cast<void> (0) : __assert_fail ("&I == HoistPoint && \"HoistPoint must be the first one in Selects\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 737, __PRETTY_FUNCTION__))
737 "HoistPoint must be the first one in Selects")((&I == HoistPoint && "HoistPoint must be the first one in Selects"
) ? static_cast<void> (0) : __assert_fail ("&I == HoistPoint && \"HoistPoint must be the first one in Selects\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 737, __PRETTY_FUNCTION__))
;
738 break;
739 }
740 }
741#endif
742 return HoistPoint;
743}
744
745// Find a CHR scope in the given region.
746CHRScope * CHR::findScope(Region *R) {
747 CHRScope *Result = nullptr;
748 BasicBlock *Entry = R->getEntry();
749 BasicBlock *Exit = R->getExit(); // null if top level.
750 assert(Entry && "Entry must not be null")((Entry && "Entry must not be null") ? static_cast<
void> (0) : __assert_fail ("Entry && \"Entry must not be null\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 750, __PRETTY_FUNCTION__))
;
751 assert((Exit == nullptr) == (R->isTopLevelRegion()) &&(((Exit == nullptr) == (R->isTopLevelRegion()) && "Only top level region has a null exit"
) ? static_cast<void> (0) : __assert_fail ("(Exit == nullptr) == (R->isTopLevelRegion()) && \"Only top level region has a null exit\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 752, __PRETTY_FUNCTION__))
752 "Only top level region has a null exit")(((Exit == nullptr) == (R->isTopLevelRegion()) && "Only top level region has a null exit"
) ? static_cast<void> (0) : __assert_fail ("(Exit == nullptr) == (R->isTopLevelRegion()) && \"Only top level region has a null exit\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 752, __PRETTY_FUNCTION__))
;
753 if (Entry)
754 CHR_DEBUG(dbgs() << "Entry " << Entry->getName() << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Entry " << Entry->getName
() << "\n"; } } while (false)
;
755 else
756 CHR_DEBUG(dbgs() << "Entry null\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Entry null\n"; } } while (false)
;
757 if (Exit)
758 CHR_DEBUG(dbgs() << "Exit " << Exit->getName() << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Exit " << Exit->getName(
) << "\n"; } } while (false)
;
759 else
760 CHR_DEBUG(dbgs() << "Exit null\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Exit null\n"; } } while (false)
;
761 // Exclude cases where Entry is part of a subregion (hence it doesn't belong
762 // to this region).
763 bool EntryInSubregion = RI.getRegionFor(Entry) != R;
764 if (EntryInSubregion)
765 return nullptr;
766 // Exclude loops
767 for (BasicBlock *Pred : predecessors(Entry))
768 if (R->contains(Pred))
769 return nullptr;
770 if (Exit) {
771 // Try to find an if-then block (check if R is an if-then).
772 // if (cond) {
773 // ...
774 // }
775 auto *BI = dyn_cast<BranchInst>(Entry->getTerminator());
776 if (BI)
777 CHR_DEBUG(dbgs() << "BI.isConditional " << BI->isConditional() << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "BI.isConditional " << BI->
isConditional() << "\n"; } } while (false)
;
778 else
779 CHR_DEBUG(dbgs() << "BI null\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "BI null\n"; } } while (false)
;
780 if (BI && BI->isConditional()) {
781 BasicBlock *S0 = BI->getSuccessor(0);
782 BasicBlock *S1 = BI->getSuccessor(1);
783 CHR_DEBUG(dbgs() << "S0 " << S0->getName() << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "S0 " << S0->getName() <<
"\n"; } } while (false)
;
784 CHR_DEBUG(dbgs() << "S1 " << S1->getName() << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "S1 " << S1->getName() <<
"\n"; } } while (false)
;
785 if (S0 != S1 && (S0 == Exit || S1 == Exit)) {
786 RegInfo RI(R);
787 RI.HasBranch = checkBiasedBranch(
788 BI, R, TrueBiasedRegionsGlobal, FalseBiasedRegionsGlobal,
789 BranchBiasMap);
790 Result = new CHRScope(RI);
791 Scopes.insert(Result);
792 CHR_DEBUG(dbgs() << "Found a region with a branch\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Found a region with a branch\n"; }
} while (false)
;
793 ++Stats.NumBranches;
794 if (!RI.HasBranch) {
795 ORE.emit([&]() {
796 return OptimizationRemarkMissed(DEBUG_TYPE"chr", "BranchNotBiased", BI)
797 << "Branch not biased";
798 });
799 }
800 }
801 }
802 }
803 {
804 // Try to look for selects in the direct child blocks (as opposed to in
805 // subregions) of R.
806 // ...
807 // if (..) { // Some subregion
808 // ...
809 // }
810 // if (..) { // Some subregion
811 // ...
812 // }
813 // ...
814 // a = cond ? b : c;
815 // ...
816 SmallVector<SelectInst *, 8> Selects;
817 for (RegionNode *E : R->elements()) {
818 if (E->isSubRegion())
819 continue;
820 // This returns the basic block of E if E is a direct child of R (not a
821 // subregion.)
822 BasicBlock *BB = E->getEntry();
823 // Need to push in the order to make it easier to find the first Select
824 // later.
825 for (Instruction &I : *BB) {
826 if (auto *SI = dyn_cast<SelectInst>(&I)) {
827 Selects.push_back(SI);
828 ++Stats.NumBranches;
829 }
830 }
831 }
832 if (Selects.size() > 0) {
833 auto AddSelects = [&](RegInfo &RI) {
834 for (auto *SI : Selects)
835 if (checkBiasedSelect(SI, RI.R,
836 TrueBiasedSelectsGlobal,
837 FalseBiasedSelectsGlobal,
838 SelectBiasMap))
839 RI.Selects.push_back(SI);
840 else
841 ORE.emit([&]() {
842 return OptimizationRemarkMissed(DEBUG_TYPE"chr", "SelectNotBiased", SI)
843 << "Select not biased";
844 });
845 };
846 if (!Result) {
847 CHR_DEBUG(dbgs() << "Found a select-only region\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Found a select-only region\n"; } }
while (false)
;
848 RegInfo RI(R);
849 AddSelects(RI);
850 Result = new CHRScope(RI);
851 Scopes.insert(Result);
852 } else {
853 CHR_DEBUG(dbgs() << "Found select(s) in a region with a branch\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Found select(s) in a region with a branch\n"
; } } while (false)
;
854 AddSelects(Result->RegInfos[0]);
855 }
856 }
857 }
858
859 if (Result) {
860 checkScopeHoistable(Result);
861 }
862 return Result;
863}
864
865// Check that any of the branch and the selects in the region could be
866// hoisted above the the CHR branch insert point (the most dominating of
867// them, either the branch (at the end of the first block) or the first
868// select in the first block). If the branch can't be hoisted, drop the
869// selects in the first blocks.
870//
871// For example, for the following scope/region with selects, we want to insert
872// the merged branch right before the first select in the first/entry block by
873// hoisting c1, c2, c3, and c4.
874//
875// // Branch insert point here.
876// a = c1 ? b : c; // Select 1
877// d = c2 ? e : f; // Select 2
878// if (c3) { // Branch
879// ...
880// c4 = foo() // A call.
881// g = c4 ? h : i; // Select 3
882// }
883//
884// But suppose we can't hoist c4 because it's dependent on the preceding
885// call. Then, we drop Select 3. Furthermore, if we can't hoist c2, we also drop
886// Select 2. If we can't hoist c3, we drop Selects 1 & 2.
887void CHR::checkScopeHoistable(CHRScope *Scope) {
888 RegInfo &RI = Scope->RegInfos[0];
889 Region *R = RI.R;
890 BasicBlock *EntryBB = R->getEntry();
891 auto *Branch = RI.HasBranch ?
892 cast<BranchInst>(EntryBB->getTerminator()) : nullptr;
893 SmallVector<SelectInst *, 8> &Selects = RI.Selects;
894 if (RI.HasBranch || !Selects.empty()) {
895 Instruction *InsertPoint = getBranchInsertPoint(RI);
896 CHR_DEBUG(dbgs() << "InsertPoint " << *InsertPoint << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "InsertPoint " << *InsertPoint
<< "\n"; } } while (false)
;
897 // Avoid a data dependence from a select or a branch to a(nother)
898 // select. Note no instruction can't data-depend on a branch (a branch
899 // instruction doesn't produce a value).
900 DenseSet<Instruction *> Unhoistables;
901 // Initialize Unhoistables with the selects.
902 for (SelectInst *SI : Selects) {
903 Unhoistables.insert(SI);
904 }
905 // Remove Selects that can't be hoisted.
906 for (auto it = Selects.begin(); it != Selects.end(); ) {
907 SelectInst *SI = *it;
908 if (SI == InsertPoint) {
909 ++it;
910 continue;
911 }
912 DenseMap<Instruction *, bool> Visited;
913 bool IsHoistable = checkHoistValue(SI->getCondition(), InsertPoint,
914 DT, Unhoistables, nullptr, Visited);
915 if (!IsHoistable) {
916 CHR_DEBUG(dbgs() << "Dropping select " << *SI << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Dropping select " << *SI <<
"\n"; } } while (false)
;
917 ORE.emit([&]() {
918 return OptimizationRemarkMissed(DEBUG_TYPE"chr",
919 "DropUnhoistableSelect", SI)
920 << "Dropped unhoistable select";
921 });
922 it = Selects.erase(it);
923 // Since we are dropping the select here, we also drop it from
924 // Unhoistables.
925 Unhoistables.erase(SI);
926 } else
927 ++it;
928 }
929 // Update InsertPoint after potentially removing selects.
930 InsertPoint = getBranchInsertPoint(RI);
931 CHR_DEBUG(dbgs() << "InsertPoint " << *InsertPoint << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "InsertPoint " << *InsertPoint
<< "\n"; } } while (false)
;
932 if (RI.HasBranch && InsertPoint != Branch) {
933 DenseMap<Instruction *, bool> Visited;
934 bool IsHoistable = checkHoistValue(Branch->getCondition(), InsertPoint,
935 DT, Unhoistables, nullptr, Visited);
936 if (!IsHoistable) {
937 // If the branch isn't hoistable, drop the selects in the entry
938 // block, preferring the branch, which makes the branch the hoist
939 // point.
940 assert(InsertPoint != Branch && "Branch must not be the hoist point")((InsertPoint != Branch && "Branch must not be the hoist point"
) ? static_cast<void> (0) : __assert_fail ("InsertPoint != Branch && \"Branch must not be the hoist point\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 940, __PRETTY_FUNCTION__))
;
941 CHR_DEBUG(dbgs() << "Dropping selects in entry block \n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Dropping selects in entry block \n"
; } } while (false)
;
942 CHR_DEBUG(do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { for (SelectInst *SI : Selects) { dbgs() << "SI "
<< *SI << "\n"; }; } } while (false)
943 for (SelectInst *SI : Selects) {do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { for (SelectInst *SI : Selects) { dbgs() << "SI "
<< *SI << "\n"; }; } } while (false)
944 dbgs() << "SI " << *SI << "\n";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { for (SelectInst *SI : Selects) { dbgs() << "SI "
<< *SI << "\n"; }; } } while (false)
945 })do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { for (SelectInst *SI : Selects) { dbgs() << "SI "
<< *SI << "\n"; }; } } while (false)
;
946 for (SelectInst *SI : Selects) {
947 ORE.emit([&]() {
948 return OptimizationRemarkMissed(DEBUG_TYPE"chr",
949 "DropSelectUnhoistableBranch", SI)
950 << "Dropped select due to unhoistable branch";
951 });
952 }
953 Selects.erase(std::remove_if(Selects.begin(), Selects.end(),
954 [EntryBB](SelectInst *SI) {
955 return SI->getParent() == EntryBB;
956 }), Selects.end());
957 Unhoistables.clear();
958 InsertPoint = Branch;
959 }
960 }
961 CHR_DEBUG(dbgs() << "InsertPoint " << *InsertPoint << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "InsertPoint " << *InsertPoint
<< "\n"; } } while (false)
;
962#ifndef NDEBUG
963 if (RI.HasBranch) {
964 assert(!DT.dominates(Branch, InsertPoint) &&((!DT.dominates(Branch, InsertPoint) && "Branch can't be already above the hoist point"
) ? static_cast<void> (0) : __assert_fail ("!DT.dominates(Branch, InsertPoint) && \"Branch can't be already above the hoist point\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 965, __PRETTY_FUNCTION__))
965 "Branch can't be already above the hoist point")((!DT.dominates(Branch, InsertPoint) && "Branch can't be already above the hoist point"
) ? static_cast<void> (0) : __assert_fail ("!DT.dominates(Branch, InsertPoint) && \"Branch can't be already above the hoist point\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 965, __PRETTY_FUNCTION__))
;
966 DenseMap<Instruction *, bool> Visited;
967 assert(checkHoistValue(Branch->getCondition(), InsertPoint,((checkHoistValue(Branch->getCondition(), InsertPoint, DT,
Unhoistables, nullptr, Visited) && "checkHoistValue for branch"
) ? static_cast<void> (0) : __assert_fail ("checkHoistValue(Branch->getCondition(), InsertPoint, DT, Unhoistables, nullptr, Visited) && \"checkHoistValue for branch\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 969, __PRETTY_FUNCTION__))
968 DT, Unhoistables, nullptr, Visited) &&((checkHoistValue(Branch->getCondition(), InsertPoint, DT,
Unhoistables, nullptr, Visited) && "checkHoistValue for branch"
) ? static_cast<void> (0) : __assert_fail ("checkHoistValue(Branch->getCondition(), InsertPoint, DT, Unhoistables, nullptr, Visited) && \"checkHoistValue for branch\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 969, __PRETTY_FUNCTION__))
969 "checkHoistValue for branch")((checkHoistValue(Branch->getCondition(), InsertPoint, DT,
Unhoistables, nullptr, Visited) && "checkHoistValue for branch"
) ? static_cast<void> (0) : __assert_fail ("checkHoistValue(Branch->getCondition(), InsertPoint, DT, Unhoistables, nullptr, Visited) && \"checkHoistValue for branch\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 969, __PRETTY_FUNCTION__))
;
970 }
971 for (auto *SI : Selects) {
972 assert(!DT.dominates(SI, InsertPoint) &&((!DT.dominates(SI, InsertPoint) && "SI can't be already above the hoist point"
) ? static_cast<void> (0) : __assert_fail ("!DT.dominates(SI, InsertPoint) && \"SI can't be already above the hoist point\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 973, __PRETTY_FUNCTION__))
973 "SI can't be already above the hoist point")((!DT.dominates(SI, InsertPoint) && "SI can't be already above the hoist point"
) ? static_cast<void> (0) : __assert_fail ("!DT.dominates(SI, InsertPoint) && \"SI can't be already above the hoist point\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 973, __PRETTY_FUNCTION__))
;
974 DenseMap<Instruction *, bool> Visited;
975 assert(checkHoistValue(SI->getCondition(), InsertPoint, DT,((checkHoistValue(SI->getCondition(), InsertPoint, DT, Unhoistables
, nullptr, Visited) && "checkHoistValue for selects")
? static_cast<void> (0) : __assert_fail ("checkHoistValue(SI->getCondition(), InsertPoint, DT, Unhoistables, nullptr, Visited) && \"checkHoistValue for selects\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 977, __PRETTY_FUNCTION__))
976 Unhoistables, nullptr, Visited) &&((checkHoistValue(SI->getCondition(), InsertPoint, DT, Unhoistables
, nullptr, Visited) && "checkHoistValue for selects")
? static_cast<void> (0) : __assert_fail ("checkHoistValue(SI->getCondition(), InsertPoint, DT, Unhoistables, nullptr, Visited) && \"checkHoistValue for selects\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 977, __PRETTY_FUNCTION__))
977 "checkHoistValue for selects")((checkHoistValue(SI->getCondition(), InsertPoint, DT, Unhoistables
, nullptr, Visited) && "checkHoistValue for selects")
? static_cast<void> (0) : __assert_fail ("checkHoistValue(SI->getCondition(), InsertPoint, DT, Unhoistables, nullptr, Visited) && \"checkHoistValue for selects\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 977, __PRETTY_FUNCTION__))
;
978 }
979 CHR_DEBUG(dbgs() << "Result\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Result\n"; } } while (false)
;
980 if (RI.HasBranch) {
981 CHR_DEBUG(dbgs() << "BI " << *Branch << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "BI " << *Branch << "\n"
; } } while (false)
;
982 }
983 for (auto *SI : Selects) {
984 CHR_DEBUG(dbgs() << "SI " << *SI << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "SI " << *SI << "\n"; }
} while (false)
;
985 }
986#endif
987 }
988}
989
990// Traverse the region tree, find all nested scopes and merge them if possible.
991CHRScope * CHR::findScopes(Region *R, Region *NextRegion, Region *ParentRegion,
992 SmallVectorImpl<CHRScope *> &Scopes) {
993 CHR_DEBUG(dbgs() << "findScopes " << R->getNameStr() << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "findScopes " << R->getNameStr
() << "\n"; } } while (false)
;
994 CHRScope *Result = findScope(R);
995 // Visit subscopes.
996 CHRScope *ConsecutiveSubscope = nullptr;
997 SmallVector<CHRScope *, 8> Subscopes;
998 for (auto It = R->begin(); It != R->end(); ++It) {
999 const std::unique_ptr<Region> &SubR = *It;
1000 auto NextIt = std::next(It);
1001 Region *NextSubR = NextIt != R->end() ? NextIt->get() : nullptr;
1002 CHR_DEBUG(dbgs() << "Looking at subregion " << SubR.get()->getNameStr()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Looking at subregion " << SubR
.get()->getNameStr() << "\n"; } } while (false)
1003 << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Looking at subregion " << SubR
.get()->getNameStr() << "\n"; } } while (false)
;
1004 CHRScope *SubCHRScope = findScopes(SubR.get(), NextSubR, R, Scopes);
1005 if (SubCHRScope) {
1006 CHR_DEBUG(dbgs() << "Subregion Scope " << *SubCHRScope << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Subregion Scope " << *SubCHRScope
<< "\n"; } } while (false)
;
1007 } else {
1008 CHR_DEBUG(dbgs() << "Subregion Scope null\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Subregion Scope null\n"; } } while
(false)
;
1009 }
1010 if (SubCHRScope) {
1011 if (!ConsecutiveSubscope)
1012 ConsecutiveSubscope = SubCHRScope;
1013 else if (!ConsecutiveSubscope->appendable(SubCHRScope)) {
1014 Subscopes.push_back(ConsecutiveSubscope);
1015 ConsecutiveSubscope = SubCHRScope;
1016 } else
1017 ConsecutiveSubscope->append(SubCHRScope);
1018 } else {
1019 if (ConsecutiveSubscope) {
1020 Subscopes.push_back(ConsecutiveSubscope);
1021 }
1022 ConsecutiveSubscope = nullptr;
1023 }
1024 }
1025 if (ConsecutiveSubscope) {
1026 Subscopes.push_back(ConsecutiveSubscope);
1027 }
1028 for (CHRScope *Sub : Subscopes) {
1029 if (Result) {
1030 // Combine it with the parent.
1031 Result->addSub(Sub);
1032 } else {
1033 // Push Subscopes as they won't be combined with the parent.
1034 Scopes.push_back(Sub);
1035 }
1036 }
1037 return Result;
1038}
1039
1040static DenseSet<Value *> getCHRConditionValuesForRegion(RegInfo &RI) {
1041 DenseSet<Value *> ConditionValues;
1042 if (RI.HasBranch) {
1043 auto *BI = cast<BranchInst>(RI.R->getEntry()->getTerminator());
1044 ConditionValues.insert(BI->getCondition());
1045 }
1046 for (SelectInst *SI : RI.Selects) {
1047 ConditionValues.insert(SI->getCondition());
1048 }
1049 return ConditionValues;
1050}
1051
1052
1053// Determine whether to split a scope depending on the sets of the branch
1054// condition values of the previous region and the current region. We split
1055// (return true) it if 1) the condition values of the inner/lower scope can't be
1056// hoisted up to the outer/upper scope, or 2) the two sets of the condition
1057// values have an empty intersection (because the combined branch conditions
1058// won't probably lead to a simpler combined condition).
1059static bool shouldSplit(Instruction *InsertPoint,
1060 DenseSet<Value *> &PrevConditionValues,
1061 DenseSet<Value *> &ConditionValues,
1062 DominatorTree &DT,
1063 DenseSet<Instruction *> &Unhoistables) {
1064 CHR_DEBUG(do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "shouldSplit " << *InsertPoint
<< " PrevConditionValues "; for (Value *V : PrevConditionValues
) { dbgs() << *V << ", "; } dbgs() << " ConditionValues "
; for (Value *V : ConditionValues) { dbgs() << *V <<
", "; } dbgs() << "\n"; } } while (false)
27
Assuming 'DebugFlag' is true
28
Assuming the condition is true
29
Taking true branch
30
Forming reference to null pointer
1065 dbgs() << "shouldSplit " << *InsertPoint << " PrevConditionValues ";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "shouldSplit " << *InsertPoint
<< " PrevConditionValues "; for (Value *V : PrevConditionValues
) { dbgs() << *V << ", "; } dbgs() << " ConditionValues "
; for (Value *V : ConditionValues) { dbgs() << *V <<
", "; } dbgs() << "\n"; } } while (false)
1066 for (Value *V : PrevConditionValues) {do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "shouldSplit " << *InsertPoint
<< " PrevConditionValues "; for (Value *V : PrevConditionValues
) { dbgs() << *V << ", "; } dbgs() << " ConditionValues "
; for (Value *V : ConditionValues) { dbgs() << *V <<
", "; } dbgs() << "\n"; } } while (false)
1067 dbgs() << *V << ", ";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "shouldSplit " << *InsertPoint
<< " PrevConditionValues "; for (Value *V : PrevConditionValues
) { dbgs() << *V << ", "; } dbgs() << " ConditionValues "
; for (Value *V : ConditionValues) { dbgs() << *V <<
", "; } dbgs() << "\n"; } } while (false)
1068 }do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "shouldSplit " << *InsertPoint
<< " PrevConditionValues "; for (Value *V : PrevConditionValues
) { dbgs() << *V << ", "; } dbgs() << " ConditionValues "
; for (Value *V : ConditionValues) { dbgs() << *V <<
", "; } dbgs() << "\n"; } } while (false)
1069 dbgs() << " ConditionValues ";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "shouldSplit " << *InsertPoint
<< " PrevConditionValues "; for (Value *V : PrevConditionValues
) { dbgs() << *V << ", "; } dbgs() << " ConditionValues "
; for (Value *V : ConditionValues) { dbgs() << *V <<
", "; } dbgs() << "\n"; } } while (false)
1070 for (Value *V : ConditionValues) {do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "shouldSplit " << *InsertPoint
<< " PrevConditionValues "; for (Value *V : PrevConditionValues
) { dbgs() << *V << ", "; } dbgs() << " ConditionValues "
; for (Value *V : ConditionValues) { dbgs() << *V <<
", "; } dbgs() << "\n"; } } while (false)
1071 dbgs() << *V << ", ";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "shouldSplit " << *InsertPoint
<< " PrevConditionValues "; for (Value *V : PrevConditionValues
) { dbgs() << *V << ", "; } dbgs() << " ConditionValues "
; for (Value *V : ConditionValues) { dbgs() << *V <<
", "; } dbgs() << "\n"; } } while (false)
1072 }do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "shouldSplit " << *InsertPoint
<< " PrevConditionValues "; for (Value *V : PrevConditionValues
) { dbgs() << *V << ", "; } dbgs() << " ConditionValues "
; for (Value *V : ConditionValues) { dbgs() << *V <<
", "; } dbgs() << "\n"; } } while (false)
1073 dbgs() << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "shouldSplit " << *InsertPoint
<< " PrevConditionValues "; for (Value *V : PrevConditionValues
) { dbgs() << *V << ", "; } dbgs() << " ConditionValues "
; for (Value *V : ConditionValues) { dbgs() << *V <<
", "; } dbgs() << "\n"; } } while (false)
;
1074 assert(InsertPoint && "Null InsertPoint")((InsertPoint && "Null InsertPoint") ? static_cast<
void> (0) : __assert_fail ("InsertPoint && \"Null InsertPoint\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1074, __PRETTY_FUNCTION__))
;
1075 // If any of Bases isn't hoistable to the hoist point, split.
1076 for (Value *V : ConditionValues) {
1077 DenseMap<Instruction *, bool> Visited;
1078 if (!checkHoistValue(V, InsertPoint, DT, Unhoistables, nullptr, Visited)) {
1079 CHR_DEBUG(dbgs() << "Split. checkHoistValue false " << *V << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Split. checkHoistValue false " <<
*V << "\n"; } } while (false)
;
1080 return true; // Not hoistable, split.
1081 }
1082 }
1083 // If PrevConditionValues or ConditionValues is empty, don't split to avoid
1084 // unnecessary splits at scopes with no branch/selects. If
1085 // PrevConditionValues and ConditionValues don't intersect at all, split.
1086 if (!PrevConditionValues.empty() && !ConditionValues.empty()) {
1087 // Use std::set as DenseSet doesn't work with set_intersection.
1088 std::set<Value *> PrevBases, Bases;
1089 DenseMap<Value *, std::set<Value *>> Visited;
1090 for (Value *V : PrevConditionValues) {
1091 std::set<Value *> BaseValues = getBaseValues(V, DT, Visited);
1092 PrevBases.insert(BaseValues.begin(), BaseValues.end());
1093 }
1094 for (Value *V : ConditionValues) {
1095 std::set<Value *> BaseValues = getBaseValues(V, DT, Visited);
1096 Bases.insert(BaseValues.begin(), BaseValues.end());
1097 }
1098 CHR_DEBUG(do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "PrevBases "; for (Value *V : PrevBases
) { dbgs() << *V << ", "; } dbgs() << " Bases "
; for (Value *V : Bases) { dbgs() << *V << ", "; }
dbgs() << "\n"; } } while (false)
1099 dbgs() << "PrevBases ";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "PrevBases "; for (Value *V : PrevBases
) { dbgs() << *V << ", "; } dbgs() << " Bases "
; for (Value *V : Bases) { dbgs() << *V << ", "; }
dbgs() << "\n"; } } while (false)
1100 for (Value *V : PrevBases) {do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "PrevBases "; for (Value *V : PrevBases
) { dbgs() << *V << ", "; } dbgs() << " Bases "
; for (Value *V : Bases) { dbgs() << *V << ", "; }
dbgs() << "\n"; } } while (false)
1101 dbgs() << *V << ", ";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "PrevBases "; for (Value *V : PrevBases
) { dbgs() << *V << ", "; } dbgs() << " Bases "
; for (Value *V : Bases) { dbgs() << *V << ", "; }
dbgs() << "\n"; } } while (false)
1102 }do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "PrevBases "; for (Value *V : PrevBases
) { dbgs() << *V << ", "; } dbgs() << " Bases "
; for (Value *V : Bases) { dbgs() << *V << ", "; }
dbgs() << "\n"; } } while (false)
1103 dbgs() << " Bases ";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "PrevBases "; for (Value *V : PrevBases
) { dbgs() << *V << ", "; } dbgs() << " Bases "
; for (Value *V : Bases) { dbgs() << *V << ", "; }
dbgs() << "\n"; } } while (false)
1104 for (Value *V : Bases) {do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "PrevBases "; for (Value *V : PrevBases
) { dbgs() << *V << ", "; } dbgs() << " Bases "
; for (Value *V : Bases) { dbgs() << *V << ", "; }
dbgs() << "\n"; } } while (false)
1105 dbgs() << *V << ", ";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "PrevBases "; for (Value *V : PrevBases
) { dbgs() << *V << ", "; } dbgs() << " Bases "
; for (Value *V : Bases) { dbgs() << *V << ", "; }
dbgs() << "\n"; } } while (false)
1106 }do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "PrevBases "; for (Value *V : PrevBases
) { dbgs() << *V << ", "; } dbgs() << " Bases "
; for (Value *V : Bases) { dbgs() << *V << ", "; }
dbgs() << "\n"; } } while (false)
1107 dbgs() << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "PrevBases "; for (Value *V : PrevBases
) { dbgs() << *V << ", "; } dbgs() << " Bases "
; for (Value *V : Bases) { dbgs() << *V << ", "; }
dbgs() << "\n"; } } while (false)
;
1108 std::set<Value *> Intersection;
1109 std::set_intersection(PrevBases.begin(), PrevBases.end(),
1110 Bases.begin(), Bases.end(),
1111 std::inserter(Intersection, Intersection.begin()));
1112 if (Intersection.empty()) {
1113 // Empty intersection, split.
1114 CHR_DEBUG(dbgs() << "Split. Intersection empty\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Split. Intersection empty\n"; } }
while (false)
;
1115 return true;
1116 }
1117 }
1118 CHR_DEBUG(dbgs() << "No split\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "No split\n"; } } while (false)
;
1119 return false; // Don't split.
1120}
1121
1122static void getSelectsInScope(CHRScope *Scope,
1123 DenseSet<Instruction *> &Output) {
1124 for (RegInfo &RI : Scope->RegInfos)
1125 for (SelectInst *SI : RI.Selects)
1126 Output.insert(SI);
1127 for (CHRScope *Sub : Scope->Subs)
1128 getSelectsInScope(Sub, Output);
1129}
1130
1131void CHR::splitScopes(SmallVectorImpl<CHRScope *> &Input,
1132 SmallVectorImpl<CHRScope *> &Output) {
1133 for (CHRScope *Scope : Input) {
10
Assuming '__begin1' is not equal to '__end1'
1134 assert(!Scope->BranchInsertPoint &&((!Scope->BranchInsertPoint && "BranchInsertPoint must not be set"
) ? static_cast<void> (0) : __assert_fail ("!Scope->BranchInsertPoint && \"BranchInsertPoint must not be set\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1135, __PRETTY_FUNCTION__))
11
Assuming field 'BranchInsertPoint' is null
12
'?' condition is true
1135 "BranchInsertPoint must not be set")((!Scope->BranchInsertPoint && "BranchInsertPoint must not be set"
) ? static_cast<void> (0) : __assert_fail ("!Scope->BranchInsertPoint && \"BranchInsertPoint must not be set\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1135, __PRETTY_FUNCTION__))
;
1136 DenseSet<Instruction *> Unhoistables;
1137 getSelectsInScope(Scope, Unhoistables);
1138 splitScope(Scope, nullptr, nullptr, nullptr, Output, Unhoistables);
13
Calling 'CHR::splitScope'
1139 }
1140#ifndef NDEBUG
1141 for (CHRScope *Scope : Output) {
1142 assert(Scope->BranchInsertPoint && "BranchInsertPoint must be set")((Scope->BranchInsertPoint && "BranchInsertPoint must be set"
) ? static_cast<void> (0) : __assert_fail ("Scope->BranchInsertPoint && \"BranchInsertPoint must be set\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1142, __PRETTY_FUNCTION__))
;
1143 }
1144#endif
1145}
1146
1147SmallVector<CHRScope *, 8> CHR::splitScope(
1148 CHRScope *Scope,
1149 CHRScope *Outer,
1150 DenseSet<Value *> *OuterConditionValues,
1151 Instruction *OuterInsertPoint,
1152 SmallVectorImpl<CHRScope *> &Output,
1153 DenseSet<Instruction *> &Unhoistables) {
1154 if (Outer
13.1
'Outer' is null
) {
14
Taking false branch
1155 assert(OuterConditionValues && "Null OuterConditionValues")((OuterConditionValues && "Null OuterConditionValues"
) ? static_cast<void> (0) : __assert_fail ("OuterConditionValues && \"Null OuterConditionValues\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1155, __PRETTY_FUNCTION__))
;
1156 assert(OuterInsertPoint && "Null OuterInsertPoint")((OuterInsertPoint && "Null OuterInsertPoint") ? static_cast
<void> (0) : __assert_fail ("OuterInsertPoint && \"Null OuterInsertPoint\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1156, __PRETTY_FUNCTION__))
;
1157 }
1158 bool PrevSplitFromOuter = true;
1159 DenseSet<Value *> PrevConditionValues;
1160 Instruction *PrevInsertPoint = nullptr;
15
'PrevInsertPoint' initialized to a null pointer value
1161 SmallVector<CHRScope *, 8> Splits;
1162 SmallVector<bool, 8> SplitsSplitFromOuter;
1163 SmallVector<DenseSet<Value *>, 8> SplitsConditionValues;
1164 SmallVector<Instruction *, 8> SplitsInsertPoints;
1165 SmallVector<RegInfo, 8> RegInfos(Scope->RegInfos); // Copy
1166 for (RegInfo &RI : RegInfos) {
16
Assuming '__begin1' is not equal to '__end1'
1167 Instruction *InsertPoint = getBranchInsertPoint(RI);
1168 DenseSet<Value *> ConditionValues = getCHRConditionValuesForRegion(RI);
1169 CHR_DEBUG(do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "ConditionValues "; for (Value *V :
ConditionValues) { dbgs() << *V << ", "; } dbgs(
) << "\n"; } } while (false)
17
Assuming 'DebugFlag' is false
18
Loop condition is false. Exiting loop
1170 dbgs() << "ConditionValues ";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "ConditionValues "; for (Value *V :
ConditionValues) { dbgs() << *V << ", "; } dbgs(
) << "\n"; } } while (false)
1171 for (Value *V : ConditionValues) {do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "ConditionValues "; for (Value *V :
ConditionValues) { dbgs() << *V << ", "; } dbgs(
) << "\n"; } } while (false)
1172 dbgs() << *V << ", ";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "ConditionValues "; for (Value *V :
ConditionValues) { dbgs() << *V << ", "; } dbgs(
) << "\n"; } } while (false)
1173 }do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "ConditionValues "; for (Value *V :
ConditionValues) { dbgs() << *V << ", "; } dbgs(
) << "\n"; } } while (false)
1174 dbgs() << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "ConditionValues "; for (Value *V :
ConditionValues) { dbgs() << *V << ", "; } dbgs(
) << "\n"; } } while (false)
;
1175 if (RI.R == RegInfos[0].R) {
19
Assuming 'RI.R' is not equal to 'RegInfos[0].R'
20
Taking false branch
1176 // First iteration. Check to see if we should split from the outer.
1177 if (Outer) {
1178 CHR_DEBUG(dbgs() << "Outer " << *Outer << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Outer " << *Outer << "\n"
; } } while (false)
;
1179 CHR_DEBUG(dbgs() << "Should split from outer at "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Should split from outer at " <<
RI.R->getNameStr() << "\n"; } } while (false)
1180 << RI.R->getNameStr() << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Should split from outer at " <<
RI.R->getNameStr() << "\n"; } } while (false)
;
1181 if (shouldSplit(OuterInsertPoint, *OuterConditionValues,
1182 ConditionValues, DT, Unhoistables)) {
1183 PrevConditionValues = ConditionValues;
1184 PrevInsertPoint = InsertPoint;
1185 ORE.emit([&]() {
1186 return OptimizationRemarkMissed(DEBUG_TYPE"chr",
1187 "SplitScopeFromOuter",
1188 RI.R->getEntry()->getTerminator())
1189 << "Split scope from outer due to unhoistable branch/select "
1190 << "and/or lack of common condition values";
1191 });
1192 } else {
1193 // Not splitting from the outer. Use the outer bases and insert
1194 // point. Union the bases.
1195 PrevSplitFromOuter = false;
1196 PrevConditionValues = *OuterConditionValues;
1197 PrevConditionValues.insert(ConditionValues.begin(),
1198 ConditionValues.end());
1199 PrevInsertPoint = OuterInsertPoint;
1200 }
1201 } else {
1202 CHR_DEBUG(dbgs() << "Outer null\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Outer null\n"; } } while (false)
;
1203 PrevConditionValues = ConditionValues;
1204 PrevInsertPoint = InsertPoint;
1205 }
1206 } else {
1207 CHR_DEBUG(dbgs() << "Should split from prev at "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Should split from prev at " <<
RI.R->getNameStr() << "\n"; } } while (false)
21
Assuming 'DebugFlag' is true
22
Assuming the condition is false
23
Taking false branch
24
Loop condition is false. Exiting loop
1208 << RI.R->getNameStr() << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Should split from prev at " <<
RI.R->getNameStr() << "\n"; } } while (false)
;
1209 if (shouldSplit(PrevInsertPoint, PrevConditionValues, ConditionValues,
25
Passing null pointer value via 1st parameter 'InsertPoint'
26
Calling 'shouldSplit'
1210 DT, Unhoistables)) {
1211 CHRScope *Tail = Scope->split(RI.R);
1212 Scopes.insert(Tail);
1213 Splits.push_back(Scope);
1214 SplitsSplitFromOuter.push_back(PrevSplitFromOuter);
1215 SplitsConditionValues.push_back(PrevConditionValues);
1216 SplitsInsertPoints.push_back(PrevInsertPoint);
1217 Scope = Tail;
1218 PrevConditionValues = ConditionValues;
1219 PrevInsertPoint = InsertPoint;
1220 PrevSplitFromOuter = true;
1221 ORE.emit([&]() {
1222 return OptimizationRemarkMissed(DEBUG_TYPE"chr",
1223 "SplitScopeFromPrev",
1224 RI.R->getEntry()->getTerminator())
1225 << "Split scope from previous due to unhoistable branch/select "
1226 << "and/or lack of common condition values";
1227 });
1228 } else {
1229 // Not splitting. Union the bases. Keep the hoist point.
1230 PrevConditionValues.insert(ConditionValues.begin(), ConditionValues.end());
1231 }
1232 }
1233 }
1234 Splits.push_back(Scope);
1235 SplitsSplitFromOuter.push_back(PrevSplitFromOuter);
1236 SplitsConditionValues.push_back(PrevConditionValues);
1237 assert(PrevInsertPoint && "Null PrevInsertPoint")((PrevInsertPoint && "Null PrevInsertPoint") ? static_cast
<void> (0) : __assert_fail ("PrevInsertPoint && \"Null PrevInsertPoint\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1237, __PRETTY_FUNCTION__))
;
1238 SplitsInsertPoints.push_back(PrevInsertPoint);
1239 assert(Splits.size() == SplitsConditionValues.size() &&((Splits.size() == SplitsConditionValues.size() && Splits
.size() == SplitsSplitFromOuter.size() && Splits.size
() == SplitsInsertPoints.size() && "Mismatching sizes"
) ? static_cast<void> (0) : __assert_fail ("Splits.size() == SplitsConditionValues.size() && Splits.size() == SplitsSplitFromOuter.size() && Splits.size() == SplitsInsertPoints.size() && \"Mismatching sizes\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1241, __PRETTY_FUNCTION__))
1240 Splits.size() == SplitsSplitFromOuter.size() &&((Splits.size() == SplitsConditionValues.size() && Splits
.size() == SplitsSplitFromOuter.size() && Splits.size
() == SplitsInsertPoints.size() && "Mismatching sizes"
) ? static_cast<void> (0) : __assert_fail ("Splits.size() == SplitsConditionValues.size() && Splits.size() == SplitsSplitFromOuter.size() && Splits.size() == SplitsInsertPoints.size() && \"Mismatching sizes\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1241, __PRETTY_FUNCTION__))
1241 Splits.size() == SplitsInsertPoints.size() && "Mismatching sizes")((Splits.size() == SplitsConditionValues.size() && Splits
.size() == SplitsSplitFromOuter.size() && Splits.size
() == SplitsInsertPoints.size() && "Mismatching sizes"
) ? static_cast<void> (0) : __assert_fail ("Splits.size() == SplitsConditionValues.size() && Splits.size() == SplitsSplitFromOuter.size() && Splits.size() == SplitsInsertPoints.size() && \"Mismatching sizes\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1241, __PRETTY_FUNCTION__))
;
1242 for (size_t I = 0; I < Splits.size(); ++I) {
1243 CHRScope *Split = Splits[I];
1244 DenseSet<Value *> &SplitConditionValues = SplitsConditionValues[I];
1245 Instruction *SplitInsertPoint = SplitsInsertPoints[I];
1246 SmallVector<CHRScope *, 8> NewSubs;
1247 DenseSet<Instruction *> SplitUnhoistables;
1248 getSelectsInScope(Split, SplitUnhoistables);
1249 for (CHRScope *Sub : Split->Subs) {
1250 SmallVector<CHRScope *, 8> SubSplits = splitScope(
1251 Sub, Split, &SplitConditionValues, SplitInsertPoint, Output,
1252 SplitUnhoistables);
1253 NewSubs.insert(NewSubs.end(), SubSplits.begin(), SubSplits.end());
1254 }
1255 Split->Subs = NewSubs;
1256 }
1257 SmallVector<CHRScope *, 8> Result;
1258 for (size_t I = 0; I < Splits.size(); ++I) {
1259 CHRScope *Split = Splits[I];
1260 if (SplitsSplitFromOuter[I]) {
1261 // Split from the outer.
1262 Output.push_back(Split);
1263 Split->BranchInsertPoint = SplitsInsertPoints[I];
1264 CHR_DEBUG(dbgs() << "BranchInsertPoint " << *SplitsInsertPoints[I]do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "BranchInsertPoint " << *SplitsInsertPoints
[I] << "\n"; } } while (false)
1265 << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "BranchInsertPoint " << *SplitsInsertPoints
[I] << "\n"; } } while (false)
;
1266 } else {
1267 // Connected to the outer.
1268 Result.push_back(Split);
1269 }
1270 }
1271 if (!Outer)
1272 assert(Result.empty() &&((Result.empty() && "If no outer (top-level), must return no nested ones"
) ? static_cast<void> (0) : __assert_fail ("Result.empty() && \"If no outer (top-level), must return no nested ones\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1273, __PRETTY_FUNCTION__))
1273 "If no outer (top-level), must return no nested ones")((Result.empty() && "If no outer (top-level), must return no nested ones"
) ? static_cast<void> (0) : __assert_fail ("Result.empty() && \"If no outer (top-level), must return no nested ones\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1273, __PRETTY_FUNCTION__))
;
1274 return Result;
1275}
1276
1277void CHR::classifyBiasedScopes(SmallVectorImpl<CHRScope *> &Scopes) {
1278 for (CHRScope *Scope : Scopes) {
1279 assert(Scope->TrueBiasedRegions.empty() && Scope->FalseBiasedRegions.empty() && "Empty")((Scope->TrueBiasedRegions.empty() && Scope->FalseBiasedRegions
.empty() && "Empty") ? static_cast<void> (0) : __assert_fail
("Scope->TrueBiasedRegions.empty() && Scope->FalseBiasedRegions.empty() && \"Empty\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1279, __PRETTY_FUNCTION__))
;
1280 classifyBiasedScopes(Scope, Scope);
1281 CHR_DEBUG(do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "classifyBiasedScopes " << *
Scope << "\n"; dbgs() << "TrueBiasedRegions "; for
(Region *R : Scope->TrueBiasedRegions) { dbgs() << R
->getNameStr() << ", "; } dbgs() << "\n"; dbgs
() << "FalseBiasedRegions "; for (Region *R : Scope->
FalseBiasedRegions) { dbgs() << R->getNameStr() <<
", "; } dbgs() << "\n"; dbgs() << "TrueBiasedSelects "
; for (SelectInst *SI : Scope->TrueBiasedSelects) { dbgs()
<< *SI << ", "; } dbgs() << "\n"; dbgs() <<
"FalseBiasedSelects "; for (SelectInst *SI : Scope->FalseBiasedSelects
) { dbgs() << *SI << ", "; } dbgs() << "\n"
;; } } while (false)
1282 dbgs() << "classifyBiasedScopes " << *Scope << "\n";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "classifyBiasedScopes " << *
Scope << "\n"; dbgs() << "TrueBiasedRegions "; for
(Region *R : Scope->TrueBiasedRegions) { dbgs() << R
->getNameStr() << ", "; } dbgs() << "\n"; dbgs
() << "FalseBiasedRegions "; for (Region *R : Scope->
FalseBiasedRegions) { dbgs() << R->getNameStr() <<
", "; } dbgs() << "\n"; dbgs() << "TrueBiasedSelects "
; for (SelectInst *SI : Scope->TrueBiasedSelects) { dbgs()
<< *SI << ", "; } dbgs() << "\n"; dbgs() <<
"FalseBiasedSelects "; for (SelectInst *SI : Scope->FalseBiasedSelects
) { dbgs() << *SI << ", "; } dbgs() << "\n"
;; } } while (false)
1283 dbgs() << "TrueBiasedRegions ";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "classifyBiasedScopes " << *
Scope << "\n"; dbgs() << "TrueBiasedRegions "; for
(Region *R : Scope->TrueBiasedRegions) { dbgs() << R
->getNameStr() << ", "; } dbgs() << "\n"; dbgs
() << "FalseBiasedRegions "; for (Region *R : Scope->
FalseBiasedRegions) { dbgs() << R->getNameStr() <<
", "; } dbgs() << "\n"; dbgs() << "TrueBiasedSelects "
; for (SelectInst *SI : Scope->TrueBiasedSelects) { dbgs()
<< *SI << ", "; } dbgs() << "\n"; dbgs() <<
"FalseBiasedSelects "; for (SelectInst *SI : Scope->FalseBiasedSelects
) { dbgs() << *SI << ", "; } dbgs() << "\n"
;; } } while (false)
1284 for (Region *R : Scope->TrueBiasedRegions) {do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "classifyBiasedScopes " << *
Scope << "\n"; dbgs() << "TrueBiasedRegions "; for
(Region *R : Scope->TrueBiasedRegions) { dbgs() << R
->getNameStr() << ", "; } dbgs() << "\n"; dbgs
() << "FalseBiasedRegions "; for (Region *R : Scope->
FalseBiasedRegions) { dbgs() << R->getNameStr() <<
", "; } dbgs() << "\n"; dbgs() << "TrueBiasedSelects "
; for (SelectInst *SI : Scope->TrueBiasedSelects) { dbgs()
<< *SI << ", "; } dbgs() << "\n"; dbgs() <<
"FalseBiasedSelects "; for (SelectInst *SI : Scope->FalseBiasedSelects
) { dbgs() << *SI << ", "; } dbgs() << "\n"
;; } } while (false)
1285 dbgs() << R->getNameStr() << ", ";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "classifyBiasedScopes " << *
Scope << "\n"; dbgs() << "TrueBiasedRegions "; for
(Region *R : Scope->TrueBiasedRegions) { dbgs() << R
->getNameStr() << ", "; } dbgs() << "\n"; dbgs
() << "FalseBiasedRegions "; for (Region *R : Scope->
FalseBiasedRegions) { dbgs() << R->getNameStr() <<
", "; } dbgs() << "\n"; dbgs() << "TrueBiasedSelects "
; for (SelectInst *SI : Scope->TrueBiasedSelects) { dbgs()
<< *SI << ", "; } dbgs() << "\n"; dbgs() <<
"FalseBiasedSelects "; for (SelectInst *SI : Scope->FalseBiasedSelects
) { dbgs() << *SI << ", "; } dbgs() << "\n"
;; } } while (false)
1286 }do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "classifyBiasedScopes " << *
Scope << "\n"; dbgs() << "TrueBiasedRegions "; for
(Region *R : Scope->TrueBiasedRegions) { dbgs() << R
->getNameStr() << ", "; } dbgs() << "\n"; dbgs
() << "FalseBiasedRegions "; for (Region *R : Scope->
FalseBiasedRegions) { dbgs() << R->getNameStr() <<
", "; } dbgs() << "\n"; dbgs() << "TrueBiasedSelects "
; for (SelectInst *SI : Scope->TrueBiasedSelects) { dbgs()
<< *SI << ", "; } dbgs() << "\n"; dbgs() <<
"FalseBiasedSelects "; for (SelectInst *SI : Scope->FalseBiasedSelects
) { dbgs() << *SI << ", "; } dbgs() << "\n"
;; } } while (false)
1287 dbgs() << "\n";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "classifyBiasedScopes " << *
Scope << "\n"; dbgs() << "TrueBiasedRegions "; for
(Region *R : Scope->TrueBiasedRegions) { dbgs() << R
->getNameStr() << ", "; } dbgs() << "\n"; dbgs
() << "FalseBiasedRegions "; for (Region *R : Scope->
FalseBiasedRegions) { dbgs() << R->getNameStr() <<
", "; } dbgs() << "\n"; dbgs() << "TrueBiasedSelects "
; for (SelectInst *SI : Scope->TrueBiasedSelects) { dbgs()
<< *SI << ", "; } dbgs() << "\n"; dbgs() <<
"FalseBiasedSelects "; for (SelectInst *SI : Scope->FalseBiasedSelects
) { dbgs() << *SI << ", "; } dbgs() << "\n"
;; } } while (false)
1288 dbgs() << "FalseBiasedRegions ";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "classifyBiasedScopes " << *
Scope << "\n"; dbgs() << "TrueBiasedRegions "; for
(Region *R : Scope->TrueBiasedRegions) { dbgs() << R
->getNameStr() << ", "; } dbgs() << "\n"; dbgs
() << "FalseBiasedRegions "; for (Region *R : Scope->
FalseBiasedRegions) { dbgs() << R->getNameStr() <<
", "; } dbgs() << "\n"; dbgs() << "TrueBiasedSelects "
; for (SelectInst *SI : Scope->TrueBiasedSelects) { dbgs()
<< *SI << ", "; } dbgs() << "\n"; dbgs() <<
"FalseBiasedSelects "; for (SelectInst *SI : Scope->FalseBiasedSelects
) { dbgs() << *SI << ", "; } dbgs() << "\n"
;; } } while (false)
1289 for (Region *R : Scope->FalseBiasedRegions) {do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "classifyBiasedScopes " << *
Scope << "\n"; dbgs() << "TrueBiasedRegions "; for
(Region *R : Scope->TrueBiasedRegions) { dbgs() << R
->getNameStr() << ", "; } dbgs() << "\n"; dbgs
() << "FalseBiasedRegions "; for (Region *R : Scope->
FalseBiasedRegions) { dbgs() << R->getNameStr() <<
", "; } dbgs() << "\n"; dbgs() << "TrueBiasedSelects "
; for (SelectInst *SI : Scope->TrueBiasedSelects) { dbgs()
<< *SI << ", "; } dbgs() << "\n"; dbgs() <<
"FalseBiasedSelects "; for (SelectInst *SI : Scope->FalseBiasedSelects
) { dbgs() << *SI << ", "; } dbgs() << "\n"
;; } } while (false)
1290 dbgs() << R->getNameStr() << ", ";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "classifyBiasedScopes " << *
Scope << "\n"; dbgs() << "TrueBiasedRegions "; for
(Region *R : Scope->TrueBiasedRegions) { dbgs() << R
->getNameStr() << ", "; } dbgs() << "\n"; dbgs
() << "FalseBiasedRegions "; for (Region *R : Scope->
FalseBiasedRegions) { dbgs() << R->getNameStr() <<
", "; } dbgs() << "\n"; dbgs() << "TrueBiasedSelects "
; for (SelectInst *SI : Scope->TrueBiasedSelects) { dbgs()
<< *SI << ", "; } dbgs() << "\n"; dbgs() <<
"FalseBiasedSelects "; for (SelectInst *SI : Scope->FalseBiasedSelects
) { dbgs() << *SI << ", "; } dbgs() << "\n"
;; } } while (false)
1291 }do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "classifyBiasedScopes " << *
Scope << "\n"; dbgs() << "TrueBiasedRegions "; for
(Region *R : Scope->TrueBiasedRegions) { dbgs() << R
->getNameStr() << ", "; } dbgs() << "\n"; dbgs
() << "FalseBiasedRegions "; for (Region *R : Scope->
FalseBiasedRegions) { dbgs() << R->getNameStr() <<
", "; } dbgs() << "\n"; dbgs() << "TrueBiasedSelects "
; for (SelectInst *SI : Scope->TrueBiasedSelects) { dbgs()
<< *SI << ", "; } dbgs() << "\n"; dbgs() <<
"FalseBiasedSelects "; for (SelectInst *SI : Scope->FalseBiasedSelects
) { dbgs() << *SI << ", "; } dbgs() << "\n"
;; } } while (false)
1292 dbgs() << "\n";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "classifyBiasedScopes " << *
Scope << "\n"; dbgs() << "TrueBiasedRegions "; for
(Region *R : Scope->TrueBiasedRegions) { dbgs() << R
->getNameStr() << ", "; } dbgs() << "\n"; dbgs
() << "FalseBiasedRegions "; for (Region *R : Scope->
FalseBiasedRegions) { dbgs() << R->getNameStr() <<
", "; } dbgs() << "\n"; dbgs() << "TrueBiasedSelects "
; for (SelectInst *SI : Scope->TrueBiasedSelects) { dbgs()
<< *SI << ", "; } dbgs() << "\n"; dbgs() <<
"FalseBiasedSelects "; for (SelectInst *SI : Scope->FalseBiasedSelects
) { dbgs() << *SI << ", "; } dbgs() << "\n"
;; } } while (false)
1293 dbgs() << "TrueBiasedSelects ";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "classifyBiasedScopes " << *
Scope << "\n"; dbgs() << "TrueBiasedRegions "; for
(Region *R : Scope->TrueBiasedRegions) { dbgs() << R
->getNameStr() << ", "; } dbgs() << "\n"; dbgs
() << "FalseBiasedRegions "; for (Region *R : Scope->
FalseBiasedRegions) { dbgs() << R->getNameStr() <<
", "; } dbgs() << "\n"; dbgs() << "TrueBiasedSelects "
; for (SelectInst *SI : Scope->TrueBiasedSelects) { dbgs()
<< *SI << ", "; } dbgs() << "\n"; dbgs() <<
"FalseBiasedSelects "; for (SelectInst *SI : Scope->FalseBiasedSelects
) { dbgs() << *SI << ", "; } dbgs() << "\n"
;; } } while (false)
1294 for (SelectInst *SI : Scope->TrueBiasedSelects) {do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "classifyBiasedScopes " << *
Scope << "\n"; dbgs() << "TrueBiasedRegions "; for
(Region *R : Scope->TrueBiasedRegions) { dbgs() << R
->getNameStr() << ", "; } dbgs() << "\n"; dbgs
() << "FalseBiasedRegions "; for (Region *R : Scope->
FalseBiasedRegions) { dbgs() << R->getNameStr() <<
", "; } dbgs() << "\n"; dbgs() << "TrueBiasedSelects "
; for (SelectInst *SI : Scope->TrueBiasedSelects) { dbgs()
<< *SI << ", "; } dbgs() << "\n"; dbgs() <<
"FalseBiasedSelects "; for (SelectInst *SI : Scope->FalseBiasedSelects
) { dbgs() << *SI << ", "; } dbgs() << "\n"
;; } } while (false)
1295 dbgs() << *SI << ", ";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "classifyBiasedScopes " << *
Scope << "\n"; dbgs() << "TrueBiasedRegions "; for
(Region *R : Scope->TrueBiasedRegions) { dbgs() << R
->getNameStr() << ", "; } dbgs() << "\n"; dbgs
() << "FalseBiasedRegions "; for (Region *R : Scope->
FalseBiasedRegions) { dbgs() << R->getNameStr() <<
", "; } dbgs() << "\n"; dbgs() << "TrueBiasedSelects "
; for (SelectInst *SI : Scope->TrueBiasedSelects) { dbgs()
<< *SI << ", "; } dbgs() << "\n"; dbgs() <<
"FalseBiasedSelects "; for (SelectInst *SI : Scope->FalseBiasedSelects
) { dbgs() << *SI << ", "; } dbgs() << "\n"
;; } } while (false)
1296 }do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "classifyBiasedScopes " << *
Scope << "\n"; dbgs() << "TrueBiasedRegions "; for
(Region *R : Scope->TrueBiasedRegions) { dbgs() << R
->getNameStr() << ", "; } dbgs() << "\n"; dbgs
() << "FalseBiasedRegions "; for (Region *R : Scope->
FalseBiasedRegions) { dbgs() << R->getNameStr() <<
", "; } dbgs() << "\n"; dbgs() << "TrueBiasedSelects "
; for (SelectInst *SI : Scope->TrueBiasedSelects) { dbgs()
<< *SI << ", "; } dbgs() << "\n"; dbgs() <<
"FalseBiasedSelects "; for (SelectInst *SI : Scope->FalseBiasedSelects
) { dbgs() << *SI << ", "; } dbgs() << "\n"
;; } } while (false)
1297 dbgs() << "\n";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "classifyBiasedScopes " << *
Scope << "\n"; dbgs() << "TrueBiasedRegions "; for
(Region *R : Scope->TrueBiasedRegions) { dbgs() << R
->getNameStr() << ", "; } dbgs() << "\n"; dbgs
() << "FalseBiasedRegions "; for (Region *R : Scope->
FalseBiasedRegions) { dbgs() << R->getNameStr() <<
", "; } dbgs() << "\n"; dbgs() << "TrueBiasedSelects "
; for (SelectInst *SI : Scope->TrueBiasedSelects) { dbgs()
<< *SI << ", "; } dbgs() << "\n"; dbgs() <<
"FalseBiasedSelects "; for (SelectInst *SI : Scope->FalseBiasedSelects
) { dbgs() << *SI << ", "; } dbgs() << "\n"
;; } } while (false)
1298 dbgs() << "FalseBiasedSelects ";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "classifyBiasedScopes " << *
Scope << "\n"; dbgs() << "TrueBiasedRegions "; for
(Region *R : Scope->TrueBiasedRegions) { dbgs() << R
->getNameStr() << ", "; } dbgs() << "\n"; dbgs
() << "FalseBiasedRegions "; for (Region *R : Scope->
FalseBiasedRegions) { dbgs() << R->getNameStr() <<
", "; } dbgs() << "\n"; dbgs() << "TrueBiasedSelects "
; for (SelectInst *SI : Scope->TrueBiasedSelects) { dbgs()
<< *SI << ", "; } dbgs() << "\n"; dbgs() <<
"FalseBiasedSelects "; for (SelectInst *SI : Scope->FalseBiasedSelects
) { dbgs() << *SI << ", "; } dbgs() << "\n"
;; } } while (false)
1299 for (SelectInst *SI : Scope->FalseBiasedSelects) {do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "classifyBiasedScopes " << *
Scope << "\n"; dbgs() << "TrueBiasedRegions "; for
(Region *R : Scope->TrueBiasedRegions) { dbgs() << R
->getNameStr() << ", "; } dbgs() << "\n"; dbgs
() << "FalseBiasedRegions "; for (Region *R : Scope->
FalseBiasedRegions) { dbgs() << R->getNameStr() <<
", "; } dbgs() << "\n"; dbgs() << "TrueBiasedSelects "
; for (SelectInst *SI : Scope->TrueBiasedSelects) { dbgs()
<< *SI << ", "; } dbgs() << "\n"; dbgs() <<
"FalseBiasedSelects "; for (SelectInst *SI : Scope->FalseBiasedSelects
) { dbgs() << *SI << ", "; } dbgs() << "\n"
;; } } while (false)
1300 dbgs() << *SI << ", ";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "classifyBiasedScopes " << *
Scope << "\n"; dbgs() << "TrueBiasedRegions "; for
(Region *R : Scope->TrueBiasedRegions) { dbgs() << R
->getNameStr() << ", "; } dbgs() << "\n"; dbgs
() << "FalseBiasedRegions "; for (Region *R : Scope->
FalseBiasedRegions) { dbgs() << R->getNameStr() <<
", "; } dbgs() << "\n"; dbgs() << "TrueBiasedSelects "
; for (SelectInst *SI : Scope->TrueBiasedSelects) { dbgs()
<< *SI << ", "; } dbgs() << "\n"; dbgs() <<
"FalseBiasedSelects "; for (SelectInst *SI : Scope->FalseBiasedSelects
) { dbgs() << *SI << ", "; } dbgs() << "\n"
;; } } while (false)
1301 }do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "classifyBiasedScopes " << *
Scope << "\n"; dbgs() << "TrueBiasedRegions "; for
(Region *R : Scope->TrueBiasedRegions) { dbgs() << R
->getNameStr() << ", "; } dbgs() << "\n"; dbgs
() << "FalseBiasedRegions "; for (Region *R : Scope->
FalseBiasedRegions) { dbgs() << R->getNameStr() <<
", "; } dbgs() << "\n"; dbgs() << "TrueBiasedSelects "
; for (SelectInst *SI : Scope->TrueBiasedSelects) { dbgs()
<< *SI << ", "; } dbgs() << "\n"; dbgs() <<
"FalseBiasedSelects "; for (SelectInst *SI : Scope->FalseBiasedSelects
) { dbgs() << *SI << ", "; } dbgs() << "\n"
;; } } while (false)
1302 dbgs() << "\n";)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "classifyBiasedScopes " << *
Scope << "\n"; dbgs() << "TrueBiasedRegions "; for
(Region *R : Scope->TrueBiasedRegions) { dbgs() << R
->getNameStr() << ", "; } dbgs() << "\n"; dbgs
() << "FalseBiasedRegions "; for (Region *R : Scope->
FalseBiasedRegions) { dbgs() << R->getNameStr() <<
", "; } dbgs() << "\n"; dbgs() << "TrueBiasedSelects "
; for (SelectInst *SI : Scope->TrueBiasedSelects) { dbgs()
<< *SI << ", "; } dbgs() << "\n"; dbgs() <<
"FalseBiasedSelects "; for (SelectInst *SI : Scope->FalseBiasedSelects
) { dbgs() << *SI << ", "; } dbgs() << "\n"
;; } } while (false)
;
1303 }
1304}
1305
1306void CHR::classifyBiasedScopes(CHRScope *Scope, CHRScope *OutermostScope) {
1307 for (RegInfo &RI : Scope->RegInfos) {
1308 if (RI.HasBranch) {
1309 Region *R = RI.R;
1310 if (TrueBiasedRegionsGlobal.count(R) > 0)
1311 OutermostScope->TrueBiasedRegions.insert(R);
1312 else if (FalseBiasedRegionsGlobal.count(R) > 0)
1313 OutermostScope->FalseBiasedRegions.insert(R);
1314 else
1315 llvm_unreachable("Must be biased")::llvm::llvm_unreachable_internal("Must be biased", "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1315)
;
1316 }
1317 for (SelectInst *SI : RI.Selects) {
1318 if (TrueBiasedSelectsGlobal.count(SI) > 0)
1319 OutermostScope->TrueBiasedSelects.insert(SI);
1320 else if (FalseBiasedSelectsGlobal.count(SI) > 0)
1321 OutermostScope->FalseBiasedSelects.insert(SI);
1322 else
1323 llvm_unreachable("Must be biased")::llvm::llvm_unreachable_internal("Must be biased", "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1323)
;
1324 }
1325 }
1326 for (CHRScope *Sub : Scope->Subs) {
1327 classifyBiasedScopes(Sub, OutermostScope);
1328 }
1329}
1330
1331static bool hasAtLeastTwoBiasedBranches(CHRScope *Scope) {
1332 unsigned NumBiased = Scope->TrueBiasedRegions.size() +
1333 Scope->FalseBiasedRegions.size() +
1334 Scope->TrueBiasedSelects.size() +
1335 Scope->FalseBiasedSelects.size();
1336 return NumBiased >= CHRMergeThreshold;
1337}
1338
1339void CHR::filterScopes(SmallVectorImpl<CHRScope *> &Input,
1340 SmallVectorImpl<CHRScope *> &Output) {
1341 for (CHRScope *Scope : Input) {
1342 // Filter out the ones with only one region and no subs.
1343 if (!hasAtLeastTwoBiasedBranches(Scope)) {
1344 CHR_DEBUG(dbgs() << "Filtered out by biased branches truthy-regions "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Filtered out by biased branches truthy-regions "
<< Scope->TrueBiasedRegions.size() << " falsy-regions "
<< Scope->FalseBiasedRegions.size() << " true-selects "
<< Scope->TrueBiasedSelects.size() << " false-selects "
<< Scope->FalseBiasedSelects.size() << "\n"; }
} while (false)
1345 << Scope->TrueBiasedRegions.size()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Filtered out by biased branches truthy-regions "
<< Scope->TrueBiasedRegions.size() << " falsy-regions "
<< Scope->FalseBiasedRegions.size() << " true-selects "
<< Scope->TrueBiasedSelects.size() << " false-selects "
<< Scope->FalseBiasedSelects.size() << "\n"; }
} while (false)
1346 << " falsy-regions " << Scope->FalseBiasedRegions.size()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Filtered out by biased branches truthy-regions "
<< Scope->TrueBiasedRegions.size() << " falsy-regions "
<< Scope->FalseBiasedRegions.size() << " true-selects "
<< Scope->TrueBiasedSelects.size() << " false-selects "
<< Scope->FalseBiasedSelects.size() << "\n"; }
} while (false)
1347 << " true-selects " << Scope->TrueBiasedSelects.size()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Filtered out by biased branches truthy-regions "
<< Scope->TrueBiasedRegions.size() << " falsy-regions "
<< Scope->FalseBiasedRegions.size() << " true-selects "
<< Scope->TrueBiasedSelects.size() << " false-selects "
<< Scope->FalseBiasedSelects.size() << "\n"; }
} while (false)
1348 << " false-selects " << Scope->FalseBiasedSelects.size() << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Filtered out by biased branches truthy-regions "
<< Scope->TrueBiasedRegions.size() << " falsy-regions "
<< Scope->FalseBiasedRegions.size() << " true-selects "
<< Scope->TrueBiasedSelects.size() << " false-selects "
<< Scope->FalseBiasedSelects.size() << "\n"; }
} while (false)
;
1349 ORE.emit([&]() {
1350 return OptimizationRemarkMissed(
1351 DEBUG_TYPE"chr",
1352 "DropScopeWithOneBranchOrSelect",
1353 Scope->RegInfos[0].R->getEntry()->getTerminator())
1354 << "Drop scope with < "
1355 << ore::NV("CHRMergeThreshold", CHRMergeThreshold)
1356 << " biased branch(es) or select(s)";
1357 });
1358 continue;
1359 }
1360 Output.push_back(Scope);
1361 }
1362}
1363
1364void CHR::setCHRRegions(SmallVectorImpl<CHRScope *> &Input,
1365 SmallVectorImpl<CHRScope *> &Output) {
1366 for (CHRScope *Scope : Input) {
1367 assert(Scope->HoistStopMap.empty() && Scope->CHRRegions.empty() &&((Scope->HoistStopMap.empty() && Scope->CHRRegions
.empty() && "Empty") ? static_cast<void> (0) : __assert_fail
("Scope->HoistStopMap.empty() && Scope->CHRRegions.empty() && \"Empty\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1368, __PRETTY_FUNCTION__))
1368 "Empty")((Scope->HoistStopMap.empty() && Scope->CHRRegions
.empty() && "Empty") ? static_cast<void> (0) : __assert_fail
("Scope->HoistStopMap.empty() && Scope->CHRRegions.empty() && \"Empty\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1368, __PRETTY_FUNCTION__))
;
1369 setCHRRegions(Scope, Scope);
1370 Output.push_back(Scope);
1371 CHR_DEBUG(do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "setCHRRegions HoistStopMap " <<
*Scope << "\n"; for (auto pair : Scope->HoistStopMap
) { Region *R = pair.first; dbgs() << "Region " <<
R->getNameStr() << "\n"; for (Instruction *I : pair
.second) { dbgs() << "HoistStop " << *I << "\n"
; } } dbgs() << "CHRRegions" << "\n"; for (RegInfo
&RI : Scope->CHRRegions) { dbgs() << RI.R->getNameStr
() << "\n"; }; } } while (false)
1372 dbgs() << "setCHRRegions HoistStopMap " << *Scope << "\n";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "setCHRRegions HoistStopMap " <<
*Scope << "\n"; for (auto pair : Scope->HoistStopMap
) { Region *R = pair.first; dbgs() << "Region " <<
R->getNameStr() << "\n"; for (Instruction *I : pair
.second) { dbgs() << "HoistStop " << *I << "\n"
; } } dbgs() << "CHRRegions" << "\n"; for (RegInfo
&RI : Scope->CHRRegions) { dbgs() << RI.R->getNameStr
() << "\n"; }; } } while (false)
1373 for (auto pair : Scope->HoistStopMap) {do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "setCHRRegions HoistStopMap " <<
*Scope << "\n"; for (auto pair : Scope->HoistStopMap
) { Region *R = pair.first; dbgs() << "Region " <<
R->getNameStr() << "\n"; for (Instruction *I : pair
.second) { dbgs() << "HoistStop " << *I << "\n"
; } } dbgs() << "CHRRegions" << "\n"; for (RegInfo
&RI : Scope->CHRRegions) { dbgs() << RI.R->getNameStr
() << "\n"; }; } } while (false)
1374 Region *R = pair.first;do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "setCHRRegions HoistStopMap " <<
*Scope << "\n"; for (auto pair : Scope->HoistStopMap
) { Region *R = pair.first; dbgs() << "Region " <<
R->getNameStr() << "\n"; for (Instruction *I : pair
.second) { dbgs() << "HoistStop " << *I << "\n"
; } } dbgs() << "CHRRegions" << "\n"; for (RegInfo
&RI : Scope->CHRRegions) { dbgs() << RI.R->getNameStr
() << "\n"; }; } } while (false)
1375 dbgs() << "Region " << R->getNameStr() << "\n";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "setCHRRegions HoistStopMap " <<
*Scope << "\n"; for (auto pair : Scope->HoistStopMap
) { Region *R = pair.first; dbgs() << "Region " <<
R->getNameStr() << "\n"; for (Instruction *I : pair
.second) { dbgs() << "HoistStop " << *I << "\n"
; } } dbgs() << "CHRRegions" << "\n"; for (RegInfo
&RI : Scope->CHRRegions) { dbgs() << RI.R->getNameStr
() << "\n"; }; } } while (false)
1376 for (Instruction *I : pair.second) {do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "setCHRRegions HoistStopMap " <<
*Scope << "\n"; for (auto pair : Scope->HoistStopMap
) { Region *R = pair.first; dbgs() << "Region " <<
R->getNameStr() << "\n"; for (Instruction *I : pair
.second) { dbgs() << "HoistStop " << *I << "\n"
; } } dbgs() << "CHRRegions" << "\n"; for (RegInfo
&RI : Scope->CHRRegions) { dbgs() << RI.R->getNameStr
() << "\n"; }; } } while (false)
1377 dbgs() << "HoistStop " << *I << "\n";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "setCHRRegions HoistStopMap " <<
*Scope << "\n"; for (auto pair : Scope->HoistStopMap
) { Region *R = pair.first; dbgs() << "Region " <<
R->getNameStr() << "\n"; for (Instruction *I : pair
.second) { dbgs() << "HoistStop " << *I << "\n"
; } } dbgs() << "CHRRegions" << "\n"; for (RegInfo
&RI : Scope->CHRRegions) { dbgs() << RI.R->getNameStr
() << "\n"; }; } } while (false)
1378 }do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "setCHRRegions HoistStopMap " <<
*Scope << "\n"; for (auto pair : Scope->HoistStopMap
) { Region *R = pair.first; dbgs() << "Region " <<
R->getNameStr() << "\n"; for (Instruction *I : pair
.second) { dbgs() << "HoistStop " << *I << "\n"
; } } dbgs() << "CHRRegions" << "\n"; for (RegInfo
&RI : Scope->CHRRegions) { dbgs() << RI.R->getNameStr
() << "\n"; }; } } while (false)
1379 }do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "setCHRRegions HoistStopMap " <<
*Scope << "\n"; for (auto pair : Scope->HoistStopMap
) { Region *R = pair.first; dbgs() << "Region " <<
R->getNameStr() << "\n"; for (Instruction *I : pair
.second) { dbgs() << "HoistStop " << *I << "\n"
; } } dbgs() << "CHRRegions" << "\n"; for (RegInfo
&RI : Scope->CHRRegions) { dbgs() << RI.R->getNameStr
() << "\n"; }; } } while (false)
1380 dbgs() << "CHRRegions" << "\n";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "setCHRRegions HoistStopMap " <<
*Scope << "\n"; for (auto pair : Scope->HoistStopMap
) { Region *R = pair.first; dbgs() << "Region " <<
R->getNameStr() << "\n"; for (Instruction *I : pair
.second) { dbgs() << "HoistStop " << *I << "\n"
; } } dbgs() << "CHRRegions" << "\n"; for (RegInfo
&RI : Scope->CHRRegions) { dbgs() << RI.R->getNameStr
() << "\n"; }; } } while (false)
1381 for (RegInfo &RI : Scope->CHRRegions) {do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "setCHRRegions HoistStopMap " <<
*Scope << "\n"; for (auto pair : Scope->HoistStopMap
) { Region *R = pair.first; dbgs() << "Region " <<
R->getNameStr() << "\n"; for (Instruction *I : pair
.second) { dbgs() << "HoistStop " << *I << "\n"
; } } dbgs() << "CHRRegions" << "\n"; for (RegInfo
&RI : Scope->CHRRegions) { dbgs() << RI.R->getNameStr
() << "\n"; }; } } while (false)
1382 dbgs() << RI.R->getNameStr() << "\n";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "setCHRRegions HoistStopMap " <<
*Scope << "\n"; for (auto pair : Scope->HoistStopMap
) { Region *R = pair.first; dbgs() << "Region " <<
R->getNameStr() << "\n"; for (Instruction *I : pair
.second) { dbgs() << "HoistStop " << *I << "\n"
; } } dbgs() << "CHRRegions" << "\n"; for (RegInfo
&RI : Scope->CHRRegions) { dbgs() << RI.R->getNameStr
() << "\n"; }; } } while (false)
1383 })do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "setCHRRegions HoistStopMap " <<
*Scope << "\n"; for (auto pair : Scope->HoistStopMap
) { Region *R = pair.first; dbgs() << "Region " <<
R->getNameStr() << "\n"; for (Instruction *I : pair
.second) { dbgs() << "HoistStop " << *I << "\n"
; } } dbgs() << "CHRRegions" << "\n"; for (RegInfo
&RI : Scope->CHRRegions) { dbgs() << RI.R->getNameStr
() << "\n"; }; } } while (false)
;
1384 }
1385}
1386
1387void CHR::setCHRRegions(CHRScope *Scope, CHRScope *OutermostScope) {
1388 DenseSet<Instruction *> Unhoistables;
1389 // Put the biased selects in Unhoistables because they should stay where they
1390 // are and constant-folded after CHR (in case one biased select or a branch
1391 // can depend on another biased select.)
1392 for (RegInfo &RI : Scope->RegInfos) {
1393 for (SelectInst *SI : RI.Selects) {
1394 Unhoistables.insert(SI);
1395 }
1396 }
1397 Instruction *InsertPoint = OutermostScope->BranchInsertPoint;
1398 for (RegInfo &RI : Scope->RegInfos) {
1399 Region *R = RI.R;
1400 DenseSet<Instruction *> HoistStops;
1401 bool IsHoisted = false;
1402 if (RI.HasBranch) {
1403 assert((OutermostScope->TrueBiasedRegions.count(R) > 0 ||(((OutermostScope->TrueBiasedRegions.count(R) > 0 || OutermostScope
->FalseBiasedRegions.count(R) > 0) && "Must be truthy or falsy"
) ? static_cast<void> (0) : __assert_fail ("(OutermostScope->TrueBiasedRegions.count(R) > 0 || OutermostScope->FalseBiasedRegions.count(R) > 0) && \"Must be truthy or falsy\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1405, __PRETTY_FUNCTION__))
1404 OutermostScope->FalseBiasedRegions.count(R) > 0) &&(((OutermostScope->TrueBiasedRegions.count(R) > 0 || OutermostScope
->FalseBiasedRegions.count(R) > 0) && "Must be truthy or falsy"
) ? static_cast<void> (0) : __assert_fail ("(OutermostScope->TrueBiasedRegions.count(R) > 0 || OutermostScope->FalseBiasedRegions.count(R) > 0) && \"Must be truthy or falsy\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1405, __PRETTY_FUNCTION__))
1405 "Must be truthy or falsy")(((OutermostScope->TrueBiasedRegions.count(R) > 0 || OutermostScope
->FalseBiasedRegions.count(R) > 0) && "Must be truthy or falsy"
) ? static_cast<void> (0) : __assert_fail ("(OutermostScope->TrueBiasedRegions.count(R) > 0 || OutermostScope->FalseBiasedRegions.count(R) > 0) && \"Must be truthy or falsy\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1405, __PRETTY_FUNCTION__))
;
1406 auto *BI = cast<BranchInst>(R->getEntry()->getTerminator());
1407 // Note checkHoistValue fills in HoistStops.
1408 DenseMap<Instruction *, bool> Visited;
1409 bool IsHoistable = checkHoistValue(BI->getCondition(), InsertPoint, DT,
1410 Unhoistables, &HoistStops, Visited);
1411 assert(IsHoistable && "Must be hoistable")((IsHoistable && "Must be hoistable") ? static_cast<
void> (0) : __assert_fail ("IsHoistable && \"Must be hoistable\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1411, __PRETTY_FUNCTION__))
;
1412 (void)(IsHoistable); // Unused in release build
1413 IsHoisted = true;
1414 }
1415 for (SelectInst *SI : RI.Selects) {
1416 assert((OutermostScope->TrueBiasedSelects.count(SI) > 0 ||(((OutermostScope->TrueBiasedSelects.count(SI) > 0 || OutermostScope
->FalseBiasedSelects.count(SI) > 0) && "Must be true or false biased"
) ? static_cast<void> (0) : __assert_fail ("(OutermostScope->TrueBiasedSelects.count(SI) > 0 || OutermostScope->FalseBiasedSelects.count(SI) > 0) && \"Must be true or false biased\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1418, __PRETTY_FUNCTION__))
1417 OutermostScope->FalseBiasedSelects.count(SI) > 0) &&(((OutermostScope->TrueBiasedSelects.count(SI) > 0 || OutermostScope
->FalseBiasedSelects.count(SI) > 0) && "Must be true or false biased"
) ? static_cast<void> (0) : __assert_fail ("(OutermostScope->TrueBiasedSelects.count(SI) > 0 || OutermostScope->FalseBiasedSelects.count(SI) > 0) && \"Must be true or false biased\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1418, __PRETTY_FUNCTION__))
1418 "Must be true or false biased")(((OutermostScope->TrueBiasedSelects.count(SI) > 0 || OutermostScope
->FalseBiasedSelects.count(SI) > 0) && "Must be true or false biased"
) ? static_cast<void> (0) : __assert_fail ("(OutermostScope->TrueBiasedSelects.count(SI) > 0 || OutermostScope->FalseBiasedSelects.count(SI) > 0) && \"Must be true or false biased\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1418, __PRETTY_FUNCTION__))
;
1419 // Note checkHoistValue fills in HoistStops.
1420 DenseMap<Instruction *, bool> Visited;
1421 bool IsHoistable = checkHoistValue(SI->getCondition(), InsertPoint, DT,
1422 Unhoistables, &HoistStops, Visited);
1423 assert(IsHoistable && "Must be hoistable")((IsHoistable && "Must be hoistable") ? static_cast<
void> (0) : __assert_fail ("IsHoistable && \"Must be hoistable\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1423, __PRETTY_FUNCTION__))
;
1424 (void)(IsHoistable); // Unused in release build
1425 IsHoisted = true;
1426 }
1427 if (IsHoisted) {
1428 OutermostScope->CHRRegions.push_back(RI);
1429 OutermostScope->HoistStopMap[R] = HoistStops;
1430 }
1431 }
1432 for (CHRScope *Sub : Scope->Subs)
1433 setCHRRegions(Sub, OutermostScope);
1434}
1435
1436bool CHRScopeSorter(CHRScope *Scope1, CHRScope *Scope2) {
1437 return Scope1->RegInfos[0].R->getDepth() < Scope2->RegInfos[0].R->getDepth();
1438}
1439
1440void CHR::sortScopes(SmallVectorImpl<CHRScope *> &Input,
1441 SmallVectorImpl<CHRScope *> &Output) {
1442 Output.resize(Input.size());
1443 llvm::copy(Input, Output.begin());
1444 llvm::stable_sort(Output, CHRScopeSorter);
1445}
1446
1447// Return true if V is already hoisted or was hoisted (along with its operands)
1448// to the insert point.
1449static void hoistValue(Value *V, Instruction *HoistPoint, Region *R,
1450 HoistStopMapTy &HoistStopMap,
1451 DenseSet<Instruction *> &HoistedSet,
1452 DenseSet<PHINode *> &TrivialPHIs,
1453 DominatorTree &DT) {
1454 auto IT = HoistStopMap.find(R);
1455 assert(IT != HoistStopMap.end() && "Region must be in hoist stop map")((IT != HoistStopMap.end() && "Region must be in hoist stop map"
) ? static_cast<void> (0) : __assert_fail ("IT != HoistStopMap.end() && \"Region must be in hoist stop map\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1455, __PRETTY_FUNCTION__))
;
1456 DenseSet<Instruction *> &HoistStops = IT->second;
1457 if (auto *I = dyn_cast<Instruction>(V)) {
1458 if (I == HoistPoint)
1459 return;
1460 if (HoistStops.count(I))
1461 return;
1462 if (auto *PN = dyn_cast<PHINode>(I))
1463 if (TrivialPHIs.count(PN))
1464 // The trivial phi inserted by the previous CHR scope could replace a
1465 // non-phi in HoistStops. Note that since this phi is at the exit of a
1466 // previous CHR scope, which dominates this scope, it's safe to stop
1467 // hoisting there.
1468 return;
1469 if (HoistedSet.count(I))
1470 // Already hoisted, return.
1471 return;
1472 assert(isHoistableInstructionType(I) && "Unhoistable instruction type")((isHoistableInstructionType(I) && "Unhoistable instruction type"
) ? static_cast<void> (0) : __assert_fail ("isHoistableInstructionType(I) && \"Unhoistable instruction type\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1472, __PRETTY_FUNCTION__))
;
1473 assert(DT.getNode(I->getParent()) && "DT must contain I's block")((DT.getNode(I->getParent()) && "DT must contain I's block"
) ? static_cast<void> (0) : __assert_fail ("DT.getNode(I->getParent()) && \"DT must contain I's block\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1473, __PRETTY_FUNCTION__))
;
1474 assert(DT.getNode(HoistPoint->getParent()) &&((DT.getNode(HoistPoint->getParent()) && "DT must contain HoistPoint block"
) ? static_cast<void> (0) : __assert_fail ("DT.getNode(HoistPoint->getParent()) && \"DT must contain HoistPoint block\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1475, __PRETTY_FUNCTION__))
1475 "DT must contain HoistPoint block")((DT.getNode(HoistPoint->getParent()) && "DT must contain HoistPoint block"
) ? static_cast<void> (0) : __assert_fail ("DT.getNode(HoistPoint->getParent()) && \"DT must contain HoistPoint block\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1475, __PRETTY_FUNCTION__))
;
1476 if (DT.dominates(I, HoistPoint))
1477 // We are already above the hoist point. Stop here. This may be necessary
1478 // when multiple scopes would independently hoist the same
1479 // instruction. Since an outer (dominating) scope would hoist it to its
1480 // entry before an inner (dominated) scope would to its entry, the inner
1481 // scope may see the instruction already hoisted, in which case it
1482 // potentially wrong for the inner scope to hoist it and could cause bad
1483 // IR (non-dominating def), but safe to skip hoisting it instead because
1484 // it's already in a block that dominates the inner scope.
1485 return;
1486 for (Value *Op : I->operands()) {
1487 hoistValue(Op, HoistPoint, R, HoistStopMap, HoistedSet, TrivialPHIs, DT);
1488 }
1489 I->moveBefore(HoistPoint);
1490 HoistedSet.insert(I);
1491 CHR_DEBUG(dbgs() << "hoistValue " << *I << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "hoistValue " << *I <<
"\n"; } } while (false)
;
1492 }
1493}
1494
1495// Hoist the dependent condition values of the branches and the selects in the
1496// scope to the insert point.
1497static void hoistScopeConditions(CHRScope *Scope, Instruction *HoistPoint,
1498 DenseSet<PHINode *> &TrivialPHIs,
1499 DominatorTree &DT) {
1500 DenseSet<Instruction *> HoistedSet;
1501 for (const RegInfo &RI : Scope->CHRRegions) {
1502 Region *R = RI.R;
1503 bool IsTrueBiased = Scope->TrueBiasedRegions.count(R);
1504 bool IsFalseBiased = Scope->FalseBiasedRegions.count(R);
1505 if (RI.HasBranch && (IsTrueBiased || IsFalseBiased)) {
1506 auto *BI = cast<BranchInst>(R->getEntry()->getTerminator());
1507 hoistValue(BI->getCondition(), HoistPoint, R, Scope->HoistStopMap,
1508 HoistedSet, TrivialPHIs, DT);
1509 }
1510 for (SelectInst *SI : RI.Selects) {
1511 bool IsTrueBiased = Scope->TrueBiasedSelects.count(SI);
1512 bool IsFalseBiased = Scope->FalseBiasedSelects.count(SI);
1513 if (!(IsTrueBiased || IsFalseBiased))
1514 continue;
1515 hoistValue(SI->getCondition(), HoistPoint, R, Scope->HoistStopMap,
1516 HoistedSet, TrivialPHIs, DT);
1517 }
1518 }
1519}
1520
1521// Negate the predicate if an ICmp if it's used only by branches or selects by
1522// swapping the operands of the branches or the selects. Returns true if success.
1523static bool negateICmpIfUsedByBranchOrSelectOnly(ICmpInst *ICmp,
1524 Instruction *ExcludedUser,
1525 CHRScope *Scope) {
1526 for (User *U : ICmp->users()) {
1527 if (U == ExcludedUser)
1528 continue;
1529 if (isa<BranchInst>(U) && cast<BranchInst>(U)->isConditional())
1530 continue;
1531 if (isa<SelectInst>(U) && cast<SelectInst>(U)->getCondition() == ICmp)
1532 continue;
1533 return false;
1534 }
1535 for (User *U : ICmp->users()) {
1536 if (U == ExcludedUser)
1537 continue;
1538 if (auto *BI = dyn_cast<BranchInst>(U)) {
1539 assert(BI->isConditional() && "Must be conditional")((BI->isConditional() && "Must be conditional") ? static_cast
<void> (0) : __assert_fail ("BI->isConditional() && \"Must be conditional\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1539, __PRETTY_FUNCTION__))
;
1540 BI->swapSuccessors();
1541 // Don't need to swap this in terms of
1542 // TrueBiasedRegions/FalseBiasedRegions because true-based/false-based
1543 // mean whehter the branch is likely go into the if-then rather than
1544 // successor0/successor1 and because we can tell which edge is the then or
1545 // the else one by comparing the destination to the region exit block.
1546 continue;
1547 }
1548 if (auto *SI = dyn_cast<SelectInst>(U)) {
1549 // Swap operands
1550 SI->swapValues();
1551 SI->swapProfMetadata();
1552 if (Scope->TrueBiasedSelects.count(SI)) {
1553 assert(Scope->FalseBiasedSelects.count(SI) == 0 &&((Scope->FalseBiasedSelects.count(SI) == 0 && "Must not be already in"
) ? static_cast<void> (0) : __assert_fail ("Scope->FalseBiasedSelects.count(SI) == 0 && \"Must not be already in\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1554, __PRETTY_FUNCTION__))
1554 "Must not be already in")((Scope->FalseBiasedSelects.count(SI) == 0 && "Must not be already in"
) ? static_cast<void> (0) : __assert_fail ("Scope->FalseBiasedSelects.count(SI) == 0 && \"Must not be already in\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1554, __PRETTY_FUNCTION__))
;
1555 Scope->FalseBiasedSelects.insert(SI);
1556 } else if (Scope->FalseBiasedSelects.count(SI)) {
1557 assert(Scope->TrueBiasedSelects.count(SI) == 0 &&((Scope->TrueBiasedSelects.count(SI) == 0 && "Must not be already in"
) ? static_cast<void> (0) : __assert_fail ("Scope->TrueBiasedSelects.count(SI) == 0 && \"Must not be already in\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1558, __PRETTY_FUNCTION__))
1558 "Must not be already in")((Scope->TrueBiasedSelects.count(SI) == 0 && "Must not be already in"
) ? static_cast<void> (0) : __assert_fail ("Scope->TrueBiasedSelects.count(SI) == 0 && \"Must not be already in\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1558, __PRETTY_FUNCTION__))
;
1559 Scope->TrueBiasedSelects.insert(SI);
1560 }
1561 continue;
1562 }
1563 llvm_unreachable("Must be a branch or a select")::llvm::llvm_unreachable_internal("Must be a branch or a select"
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1563)
;
1564 }
1565 ICmp->setPredicate(CmpInst::getInversePredicate(ICmp->getPredicate()));
1566 return true;
1567}
1568
1569// A helper for transformScopes. Insert a trivial phi at the scope exit block
1570// for a value that's defined in the scope but used outside it (meaning it's
1571// alive at the exit block).
1572static void insertTrivialPHIs(CHRScope *Scope,
1573 BasicBlock *EntryBlock, BasicBlock *ExitBlock,
1574 DenseSet<PHINode *> &TrivialPHIs) {
1575 DenseSet<BasicBlock *> BlocksInScopeSet;
1576 SmallVector<BasicBlock *, 8> BlocksInScopeVec;
1577 for (RegInfo &RI : Scope->RegInfos) {
1578 for (BasicBlock *BB : RI.R->blocks()) { // This includes the blocks in the
1579 // sub-Scopes.
1580 BlocksInScopeSet.insert(BB);
1581 BlocksInScopeVec.push_back(BB);
1582 }
1583 }
1584 CHR_DEBUG(do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Inserting redudant phis\n"; for (
BasicBlock *BB : BlocksInScopeVec) { dbgs() << "BlockInScope "
<< BB->getName() << "\n"; }; } } while (false
)
1585 dbgs() << "Inserting redudant phis\n";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Inserting redudant phis\n"; for (
BasicBlock *BB : BlocksInScopeVec) { dbgs() << "BlockInScope "
<< BB->getName() << "\n"; }; } } while (false
)
1586 for (BasicBlock *BB : BlocksInScopeVec) {do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Inserting redudant phis\n"; for (
BasicBlock *BB : BlocksInScopeVec) { dbgs() << "BlockInScope "
<< BB->getName() << "\n"; }; } } while (false
)
1587 dbgs() << "BlockInScope " << BB->getName() << "\n";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Inserting redudant phis\n"; for (
BasicBlock *BB : BlocksInScopeVec) { dbgs() << "BlockInScope "
<< BB->getName() << "\n"; }; } } while (false
)
1588 })do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Inserting redudant phis\n"; for (
BasicBlock *BB : BlocksInScopeVec) { dbgs() << "BlockInScope "
<< BB->getName() << "\n"; }; } } while (false
)
;
1589 for (BasicBlock *BB : BlocksInScopeVec) {
1590 for (Instruction &I : *BB) {
1591 SmallVector<Instruction *, 8> Users;
1592 for (User *U : I.users()) {
1593 if (auto *UI = dyn_cast<Instruction>(U)) {
1594 if (BlocksInScopeSet.count(UI->getParent()) == 0 &&
1595 // Unless there's already a phi for I at the exit block.
1596 !(isa<PHINode>(UI) && UI->getParent() == ExitBlock)) {
1597 CHR_DEBUG(dbgs() << "V " << I << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "V " << I << "\n"; } }
while (false)
;
1598 CHR_DEBUG(dbgs() << "Used outside scope by user " << *UI << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Used outside scope by user " <<
*UI << "\n"; } } while (false)
;
1599 Users.push_back(UI);
1600 } else if (UI->getParent() == EntryBlock && isa<PHINode>(UI)) {
1601 // There's a loop backedge from a block that's dominated by this
1602 // scope to the entry block.
1603 CHR_DEBUG(dbgs() << "V " << I << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "V " << I << "\n"; } }
while (false)
;
1604 CHR_DEBUG(dbgs()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Used at entry block (for a back edge) by a phi user "
<< *UI << "\n"; } } while (false)
1605 << "Used at entry block (for a back edge) by a phi user "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Used at entry block (for a back edge) by a phi user "
<< *UI << "\n"; } } while (false)
1606 << *UI << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Used at entry block (for a back edge) by a phi user "
<< *UI << "\n"; } } while (false)
;
1607 Users.push_back(UI);
1608 }
1609 }
1610 }
1611 if (Users.size() > 0) {
1612 // Insert a trivial phi for I (phi [&I, P0], [&I, P1], ...) at
1613 // ExitBlock. Replace I with the new phi in UI unless UI is another
1614 // phi at ExitBlock.
1615 unsigned PredCount = std::distance(pred_begin(ExitBlock),
1616 pred_end(ExitBlock));
1617 PHINode *PN = PHINode::Create(I.getType(), PredCount, "",
1618 &ExitBlock->front());
1619 for (BasicBlock *Pred : predecessors(ExitBlock)) {
1620 PN->addIncoming(&I, Pred);
1621 }
1622 TrivialPHIs.insert(PN);
1623 CHR_DEBUG(dbgs() << "Insert phi " << *PN << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Insert phi " << *PN <<
"\n"; } } while (false)
;
1624 for (Instruction *UI : Users) {
1625 for (unsigned J = 0, NumOps = UI->getNumOperands(); J < NumOps; ++J) {
1626 if (UI->getOperand(J) == &I) {
1627 UI->setOperand(J, PN);
1628 }
1629 }
1630 CHR_DEBUG(dbgs() << "Updated user " << *UI << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Updated user " << *UI <<
"\n"; } } while (false)
;
1631 }
1632 }
1633 }
1634 }
1635}
1636
1637// Assert that all the CHR regions of the scope have a biased branch or select.
1638static void LLVM_ATTRIBUTE_UNUSED__attribute__((__unused__))
1639assertCHRRegionsHaveBiasedBranchOrSelect(CHRScope *Scope) {
1640#ifndef NDEBUG
1641 auto HasBiasedBranchOrSelect = [](RegInfo &RI, CHRScope *Scope) {
1642 if (Scope->TrueBiasedRegions.count(RI.R) ||
1643 Scope->FalseBiasedRegions.count(RI.R))
1644 return true;
1645 for (SelectInst *SI : RI.Selects)
1646 if (Scope->TrueBiasedSelects.count(SI) ||
1647 Scope->FalseBiasedSelects.count(SI))
1648 return true;
1649 return false;
1650 };
1651 for (RegInfo &RI : Scope->CHRRegions) {
1652 assert(HasBiasedBranchOrSelect(RI, Scope) &&((HasBiasedBranchOrSelect(RI, Scope) && "Must have biased branch or select"
) ? static_cast<void> (0) : __assert_fail ("HasBiasedBranchOrSelect(RI, Scope) && \"Must have biased branch or select\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1653, __PRETTY_FUNCTION__))
1653 "Must have biased branch or select")((HasBiasedBranchOrSelect(RI, Scope) && "Must have biased branch or select"
) ? static_cast<void> (0) : __assert_fail ("HasBiasedBranchOrSelect(RI, Scope) && \"Must have biased branch or select\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1653, __PRETTY_FUNCTION__))
;
1654 }
1655#endif
1656}
1657
1658// Assert that all the condition values of the biased branches and selects have
1659// been hoisted to the pre-entry block or outside of the scope.
1660static void LLVM_ATTRIBUTE_UNUSED__attribute__((__unused__)) assertBranchOrSelectConditionHoisted(
1661 CHRScope *Scope, BasicBlock *PreEntryBlock) {
1662 CHR_DEBUG(dbgs() << "Biased regions condition values \n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Biased regions condition values \n"
; } } while (false)
;
1663 for (RegInfo &RI : Scope->CHRRegions) {
1664 Region *R = RI.R;
1665 bool IsTrueBiased = Scope->TrueBiasedRegions.count(R);
1666 bool IsFalseBiased = Scope->FalseBiasedRegions.count(R);
1667 if (RI.HasBranch && (IsTrueBiased || IsFalseBiased)) {
1668 auto *BI = cast<BranchInst>(R->getEntry()->getTerminator());
1669 Value *V = BI->getCondition();
1670 CHR_DEBUG(dbgs() << *V << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << *V << "\n"; } } while (false
)
;
1671 if (auto *I = dyn_cast<Instruction>(V)) {
1672 (void)(I); // Unused in release build.
1673 assert((I->getParent() == PreEntryBlock ||(((I->getParent() == PreEntryBlock || !Scope->contains(
I)) && "Must have been hoisted to PreEntryBlock or outside the scope"
) ? static_cast<void> (0) : __assert_fail ("(I->getParent() == PreEntryBlock || !Scope->contains(I)) && \"Must have been hoisted to PreEntryBlock or outside the scope\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1675, __PRETTY_FUNCTION__))
1674 !Scope->contains(I)) &&(((I->getParent() == PreEntryBlock || !Scope->contains(
I)) && "Must have been hoisted to PreEntryBlock or outside the scope"
) ? static_cast<void> (0) : __assert_fail ("(I->getParent() == PreEntryBlock || !Scope->contains(I)) && \"Must have been hoisted to PreEntryBlock or outside the scope\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1675, __PRETTY_FUNCTION__))
1675 "Must have been hoisted to PreEntryBlock or outside the scope")(((I->getParent() == PreEntryBlock || !Scope->contains(
I)) && "Must have been hoisted to PreEntryBlock or outside the scope"
) ? static_cast<void> (0) : __assert_fail ("(I->getParent() == PreEntryBlock || !Scope->contains(I)) && \"Must have been hoisted to PreEntryBlock or outside the scope\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1675, __PRETTY_FUNCTION__))
;
1676 }
1677 }
1678 for (SelectInst *SI : RI.Selects) {
1679 bool IsTrueBiased = Scope->TrueBiasedSelects.count(SI);
1680 bool IsFalseBiased = Scope->FalseBiasedSelects.count(SI);
1681 if (!(IsTrueBiased || IsFalseBiased))
1682 continue;
1683 Value *V = SI->getCondition();
1684 CHR_DEBUG(dbgs() << *V << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << *V << "\n"; } } while (false
)
;
1685 if (auto *I = dyn_cast<Instruction>(V)) {
1686 (void)(I); // Unused in release build.
1687 assert((I->getParent() == PreEntryBlock ||(((I->getParent() == PreEntryBlock || !Scope->contains(
I)) && "Must have been hoisted to PreEntryBlock or outside the scope"
) ? static_cast<void> (0) : __assert_fail ("(I->getParent() == PreEntryBlock || !Scope->contains(I)) && \"Must have been hoisted to PreEntryBlock or outside the scope\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1689, __PRETTY_FUNCTION__))
1688 !Scope->contains(I)) &&(((I->getParent() == PreEntryBlock || !Scope->contains(
I)) && "Must have been hoisted to PreEntryBlock or outside the scope"
) ? static_cast<void> (0) : __assert_fail ("(I->getParent() == PreEntryBlock || !Scope->contains(I)) && \"Must have been hoisted to PreEntryBlock or outside the scope\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1689, __PRETTY_FUNCTION__))
1689 "Must have been hoisted to PreEntryBlock or outside the scope")(((I->getParent() == PreEntryBlock || !Scope->contains(
I)) && "Must have been hoisted to PreEntryBlock or outside the scope"
) ? static_cast<void> (0) : __assert_fail ("(I->getParent() == PreEntryBlock || !Scope->contains(I)) && \"Must have been hoisted to PreEntryBlock or outside the scope\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1689, __PRETTY_FUNCTION__))
;
1690 }
1691 }
1692 }
1693}
1694
1695void CHR::transformScopes(CHRScope *Scope, DenseSet<PHINode *> &TrivialPHIs) {
1696 CHR_DEBUG(dbgs() << "transformScopes " << *Scope << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "transformScopes " << *Scope
<< "\n"; } } while (false)
;
1697
1698 assert(Scope->RegInfos.size() >= 1 && "Should have at least one Region")((Scope->RegInfos.size() >= 1 && "Should have at least one Region"
) ? static_cast<void> (0) : __assert_fail ("Scope->RegInfos.size() >= 1 && \"Should have at least one Region\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1698, __PRETTY_FUNCTION__))
;
1699 Region *FirstRegion = Scope->RegInfos[0].R;
1700 BasicBlock *EntryBlock = FirstRegion->getEntry();
1701 Region *LastRegion = Scope->RegInfos[Scope->RegInfos.size() - 1].R;
1702 BasicBlock *ExitBlock = LastRegion->getExit();
1703 Optional<uint64_t> ProfileCount = BFI.getBlockProfileCount(EntryBlock);
1704
1705 if (ExitBlock) {
1706 // Insert a trivial phi at the exit block (where the CHR hot path and the
1707 // cold path merges) for a value that's defined in the scope but used
1708 // outside it (meaning it's alive at the exit block). We will add the
1709 // incoming values for the CHR cold paths to it below. Without this, we'd
1710 // miss updating phi's for such values unless there happens to already be a
1711 // phi for that value there.
1712 insertTrivialPHIs(Scope, EntryBlock, ExitBlock, TrivialPHIs);
1713 }
1714
1715 // Split the entry block of the first region. The new block becomes the new
1716 // entry block of the first region. The old entry block becomes the block to
1717 // insert the CHR branch into. Note DT gets updated. Since DT gets updated
1718 // through the split, we update the entry of the first region after the split,
1719 // and Region only points to the entry and the exit blocks, rather than
1720 // keeping everything in a list or set, the blocks membership and the
1721 // entry/exit blocks of the region are still valid after the split.
1722 CHR_DEBUG(dbgs() << "Splitting entry block " << EntryBlock->getName()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Splitting entry block " << EntryBlock
->getName() << " at " << *Scope->BranchInsertPoint
<< "\n"; } } while (false)
1723 << " at " << *Scope->BranchInsertPoint << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Splitting entry block " << EntryBlock
->getName() << " at " << *Scope->BranchInsertPoint
<< "\n"; } } while (false)
;
1724 BasicBlock *NewEntryBlock =
1725 SplitBlock(EntryBlock, Scope->BranchInsertPoint, &DT);
1726 assert(NewEntryBlock->getSinglePredecessor() == EntryBlock &&((NewEntryBlock->getSinglePredecessor() == EntryBlock &&
"NewEntryBlock's only pred must be EntryBlock") ? static_cast
<void> (0) : __assert_fail ("NewEntryBlock->getSinglePredecessor() == EntryBlock && \"NewEntryBlock's only pred must be EntryBlock\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1727, __PRETTY_FUNCTION__))
1727 "NewEntryBlock's only pred must be EntryBlock")((NewEntryBlock->getSinglePredecessor() == EntryBlock &&
"NewEntryBlock's only pred must be EntryBlock") ? static_cast
<void> (0) : __assert_fail ("NewEntryBlock->getSinglePredecessor() == EntryBlock && \"NewEntryBlock's only pred must be EntryBlock\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1727, __PRETTY_FUNCTION__))
;
1728 FirstRegion->replaceEntryRecursive(NewEntryBlock);
1729 BasicBlock *PreEntryBlock = EntryBlock;
1730
1731 ValueToValueMapTy VMap;
1732 // Clone the blocks in the scope (excluding the PreEntryBlock) to split into a
1733 // hot path (originals) and a cold path (clones) and update the PHIs at the
1734 // exit block.
1735 cloneScopeBlocks(Scope, PreEntryBlock, ExitBlock, LastRegion, VMap);
1736
1737 // Replace the old (placeholder) branch with the new (merged) conditional
1738 // branch.
1739 BranchInst *MergedBr = createMergedBranch(PreEntryBlock, EntryBlock,
1740 NewEntryBlock, VMap);
1741
1742#ifndef NDEBUG
1743 assertCHRRegionsHaveBiasedBranchOrSelect(Scope);
1744#endif
1745
1746 // Hoist the conditional values of the branches/selects.
1747 hoistScopeConditions(Scope, PreEntryBlock->getTerminator(), TrivialPHIs, DT);
1748
1749#ifndef NDEBUG
1750 assertBranchOrSelectConditionHoisted(Scope, PreEntryBlock);
1751#endif
1752
1753 // Create the combined branch condition and constant-fold the branches/selects
1754 // in the hot path.
1755 fixupBranchesAndSelects(Scope, PreEntryBlock, MergedBr,
1756 ProfileCount ? ProfileCount.getValue() : 0);
1757}
1758
1759// A helper for transformScopes. Clone the blocks in the scope (excluding the
1760// PreEntryBlock) to split into a hot path and a cold path and update the PHIs
1761// at the exit block.
1762void CHR::cloneScopeBlocks(CHRScope *Scope,
1763 BasicBlock *PreEntryBlock,
1764 BasicBlock *ExitBlock,
1765 Region *LastRegion,
1766 ValueToValueMapTy &VMap) {
1767 // Clone all the blocks. The original blocks will be the hot-path
1768 // CHR-optimized code and the cloned blocks will be the original unoptimized
1769 // code. This is so that the block pointers from the
1770 // CHRScope/Region/RegionInfo can stay valid in pointing to the hot-path code
1771 // which CHR should apply to.
1772 SmallVector<BasicBlock*, 8> NewBlocks;
1773 for (RegInfo &RI : Scope->RegInfos)
1774 for (BasicBlock *BB : RI.R->blocks()) { // This includes the blocks in the
1775 // sub-Scopes.
1776 assert(BB != PreEntryBlock && "Don't copy the preetntry block")((BB != PreEntryBlock && "Don't copy the preetntry block"
) ? static_cast<void> (0) : __assert_fail ("BB != PreEntryBlock && \"Don't copy the preetntry block\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1776, __PRETTY_FUNCTION__))
;
1777 BasicBlock *NewBB = CloneBasicBlock(BB, VMap, ".nonchr", &F);
1778 NewBlocks.push_back(NewBB);
1779 VMap[BB] = NewBB;
1780 }
1781
1782 // Place the cloned blocks right after the original blocks (right before the
1783 // exit block of.)
1784 if (ExitBlock)
1785 F.getBasicBlockList().splice(ExitBlock->getIterator(),
1786 F.getBasicBlockList(),
1787 NewBlocks[0]->getIterator(), F.end());
1788
1789 // Update the cloned blocks/instructions to refer to themselves.
1790 for (unsigned i = 0, e = NewBlocks.size(); i != e; ++i)
1791 for (Instruction &I : *NewBlocks[i])
1792 RemapInstruction(&I, VMap,
1793 RF_NoModuleLevelChanges | RF_IgnoreMissingLocals);
1794
1795 // Add the cloned blocks to the PHIs of the exit blocks. ExitBlock is null for
1796 // the top-level region but we don't need to add PHIs. The trivial PHIs
1797 // inserted above will be updated here.
1798 if (ExitBlock)
1799 for (PHINode &PN : ExitBlock->phis())
1800 for (unsigned I = 0, NumOps = PN.getNumIncomingValues(); I < NumOps;
1801 ++I) {
1802 BasicBlock *Pred = PN.getIncomingBlock(I);
1803 if (LastRegion->contains(Pred)) {
1804 Value *V = PN.getIncomingValue(I);
1805 auto It = VMap.find(V);
1806 if (It != VMap.end()) V = It->second;
1807 assert(VMap.find(Pred) != VMap.end() && "Pred must have been cloned")((VMap.find(Pred) != VMap.end() && "Pred must have been cloned"
) ? static_cast<void> (0) : __assert_fail ("VMap.find(Pred) != VMap.end() && \"Pred must have been cloned\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1807, __PRETTY_FUNCTION__))
;
1808 PN.addIncoming(V, cast<BasicBlock>(VMap[Pred]));
1809 }
1810 }
1811}
1812
1813// A helper for transformScope. Replace the old (placeholder) branch with the
1814// new (merged) conditional branch.
1815BranchInst *CHR::createMergedBranch(BasicBlock *PreEntryBlock,
1816 BasicBlock *EntryBlock,
1817 BasicBlock *NewEntryBlock,
1818 ValueToValueMapTy &VMap) {
1819 BranchInst *OldBR = cast<BranchInst>(PreEntryBlock->getTerminator());
1820 assert(OldBR->isUnconditional() && OldBR->getSuccessor(0) == NewEntryBlock &&((OldBR->isUnconditional() && OldBR->getSuccessor
(0) == NewEntryBlock && "SplitBlock did not work correctly!"
) ? static_cast<void> (0) : __assert_fail ("OldBR->isUnconditional() && OldBR->getSuccessor(0) == NewEntryBlock && \"SplitBlock did not work correctly!\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1821, __PRETTY_FUNCTION__))
1821 "SplitBlock did not work correctly!")((OldBR->isUnconditional() && OldBR->getSuccessor
(0) == NewEntryBlock && "SplitBlock did not work correctly!"
) ? static_cast<void> (0) : __assert_fail ("OldBR->isUnconditional() && OldBR->getSuccessor(0) == NewEntryBlock && \"SplitBlock did not work correctly!\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1821, __PRETTY_FUNCTION__))
;
1822 assert(NewEntryBlock->getSinglePredecessor() == EntryBlock &&((NewEntryBlock->getSinglePredecessor() == EntryBlock &&
"NewEntryBlock's only pred must be EntryBlock") ? static_cast
<void> (0) : __assert_fail ("NewEntryBlock->getSinglePredecessor() == EntryBlock && \"NewEntryBlock's only pred must be EntryBlock\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1823, __PRETTY_FUNCTION__))
1823 "NewEntryBlock's only pred must be EntryBlock")((NewEntryBlock->getSinglePredecessor() == EntryBlock &&
"NewEntryBlock's only pred must be EntryBlock") ? static_cast
<void> (0) : __assert_fail ("NewEntryBlock->getSinglePredecessor() == EntryBlock && \"NewEntryBlock's only pred must be EntryBlock\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1823, __PRETTY_FUNCTION__))
;
1824 assert(VMap.find(NewEntryBlock) != VMap.end() &&((VMap.find(NewEntryBlock) != VMap.end() && "NewEntryBlock must have been copied"
) ? static_cast<void> (0) : __assert_fail ("VMap.find(NewEntryBlock) != VMap.end() && \"NewEntryBlock must have been copied\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1825, __PRETTY_FUNCTION__))
1825 "NewEntryBlock must have been copied")((VMap.find(NewEntryBlock) != VMap.end() && "NewEntryBlock must have been copied"
) ? static_cast<void> (0) : __assert_fail ("VMap.find(NewEntryBlock) != VMap.end() && \"NewEntryBlock must have been copied\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1825, __PRETTY_FUNCTION__))
;
1826 OldBR->dropAllReferences();
1827 OldBR->eraseFromParent();
1828 // The true predicate is a placeholder. It will be replaced later in
1829 // fixupBranchesAndSelects().
1830 BranchInst *NewBR = BranchInst::Create(NewEntryBlock,
1831 cast<BasicBlock>(VMap[NewEntryBlock]),
1832 ConstantInt::getTrue(F.getContext()));
1833 PreEntryBlock->getInstList().push_back(NewBR);
1834 assert(NewEntryBlock->getSinglePredecessor() == EntryBlock &&((NewEntryBlock->getSinglePredecessor() == EntryBlock &&
"NewEntryBlock's only pred must be EntryBlock") ? static_cast
<void> (0) : __assert_fail ("NewEntryBlock->getSinglePredecessor() == EntryBlock && \"NewEntryBlock's only pred must be EntryBlock\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1835, __PRETTY_FUNCTION__))
1835 "NewEntryBlock's only pred must be EntryBlock")((NewEntryBlock->getSinglePredecessor() == EntryBlock &&
"NewEntryBlock's only pred must be EntryBlock") ? static_cast
<void> (0) : __assert_fail ("NewEntryBlock->getSinglePredecessor() == EntryBlock && \"NewEntryBlock's only pred must be EntryBlock\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1835, __PRETTY_FUNCTION__))
;
1836 return NewBR;
1837}
1838
1839// A helper for transformScopes. Create the combined branch condition and
1840// constant-fold the branches/selects in the hot path.
1841void CHR::fixupBranchesAndSelects(CHRScope *Scope,
1842 BasicBlock *PreEntryBlock,
1843 BranchInst *MergedBR,
1844 uint64_t ProfileCount) {
1845 Value *MergedCondition = ConstantInt::getTrue(F.getContext());
1846 BranchProbability CHRBranchBias(1, 1);
1847 uint64_t NumCHRedBranches = 0;
1848 IRBuilder<> IRB(PreEntryBlock->getTerminator());
1849 for (RegInfo &RI : Scope->CHRRegions) {
1850 Region *R = RI.R;
1851 if (RI.HasBranch) {
1852 fixupBranch(R, Scope, IRB, MergedCondition, CHRBranchBias);
1853 ++NumCHRedBranches;
1854 }
1855 for (SelectInst *SI : RI.Selects) {
1856 fixupSelect(SI, Scope, IRB, MergedCondition, CHRBranchBias);
1857 ++NumCHRedBranches;
1858 }
1859 }
1860 Stats.NumBranchesDelta += NumCHRedBranches - 1;
1861 Stats.WeightedNumBranchesDelta += (NumCHRedBranches - 1) * ProfileCount;
1862 ORE.emit([&]() {
1863 return OptimizationRemark(DEBUG_TYPE"chr",
1864 "CHR",
1865 // Refer to the hot (original) path
1866 MergedBR->getSuccessor(0)->getTerminator())
1867 << "Merged " << ore::NV("NumCHRedBranches", NumCHRedBranches)
1868 << " branches or selects";
1869 });
1870 MergedBR->setCondition(MergedCondition);
1871 SmallVector<uint32_t, 2> Weights;
1872 Weights.push_back(static_cast<uint32_t>(CHRBranchBias.scale(1000)));
1873 Weights.push_back(static_cast<uint32_t>(CHRBranchBias.getCompl().scale(1000)));
1874 MDBuilder MDB(F.getContext());
1875 MergedBR->setMetadata(LLVMContext::MD_prof, MDB.createBranchWeights(Weights));
1876 CHR_DEBUG(dbgs() << "CHR branch bias " << Weights[0] << ":" << Weights[1]do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "CHR branch bias " << Weights
[0] << ":" << Weights[1] << "\n"; } } while
(false)
1877 << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "CHR branch bias " << Weights
[0] << ":" << Weights[1] << "\n"; } } while
(false)
;
1878}
1879
1880// A helper for fixupBranchesAndSelects. Add to the combined branch condition
1881// and constant-fold a branch in the hot path.
1882void CHR::fixupBranch(Region *R, CHRScope *Scope,
1883 IRBuilder<> &IRB,
1884 Value *&MergedCondition,
1885 BranchProbability &CHRBranchBias) {
1886 bool IsTrueBiased = Scope->TrueBiasedRegions.count(R);
1887 assert((IsTrueBiased || Scope->FalseBiasedRegions.count(R)) &&(((IsTrueBiased || Scope->FalseBiasedRegions.count(R)) &&
"Must be truthy or falsy") ? static_cast<void> (0) : __assert_fail
("(IsTrueBiased || Scope->FalseBiasedRegions.count(R)) && \"Must be truthy or falsy\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1888, __PRETTY_FUNCTION__))
1888 "Must be truthy or falsy")(((IsTrueBiased || Scope->FalseBiasedRegions.count(R)) &&
"Must be truthy or falsy") ? static_cast<void> (0) : __assert_fail
("(IsTrueBiased || Scope->FalseBiasedRegions.count(R)) && \"Must be truthy or falsy\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1888, __PRETTY_FUNCTION__))
;
1889 auto *BI = cast<BranchInst>(R->getEntry()->getTerminator());
1890 assert(BranchBiasMap.find(R) != BranchBiasMap.end() &&((BranchBiasMap.find(R) != BranchBiasMap.end() && "Must be in the bias map"
) ? static_cast<void> (0) : __assert_fail ("BranchBiasMap.find(R) != BranchBiasMap.end() && \"Must be in the bias map\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1891, __PRETTY_FUNCTION__))
1891 "Must be in the bias map")((BranchBiasMap.find(R) != BranchBiasMap.end() && "Must be in the bias map"
) ? static_cast<void> (0) : __assert_fail ("BranchBiasMap.find(R) != BranchBiasMap.end() && \"Must be in the bias map\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1891, __PRETTY_FUNCTION__))
;
1892 BranchProbability Bias = BranchBiasMap[R];
1893 assert(Bias >= getCHRBiasThreshold() && "Must be highly biased")((Bias >= getCHRBiasThreshold() && "Must be highly biased"
) ? static_cast<void> (0) : __assert_fail ("Bias >= getCHRBiasThreshold() && \"Must be highly biased\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1893, __PRETTY_FUNCTION__))
;
1894 // Take the min.
1895 if (CHRBranchBias > Bias)
1896 CHRBranchBias = Bias;
1897 BasicBlock *IfThen = BI->getSuccessor(1);
1898 BasicBlock *IfElse = BI->getSuccessor(0);
1899 BasicBlock *RegionExitBlock = R->getExit();
1900 assert(RegionExitBlock && "Null ExitBlock")((RegionExitBlock && "Null ExitBlock") ? static_cast<
void> (0) : __assert_fail ("RegionExitBlock && \"Null ExitBlock\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1900, __PRETTY_FUNCTION__))
;
1901 assert((IfThen == RegionExitBlock || IfElse == RegionExitBlock) &&(((IfThen == RegionExitBlock || IfElse == RegionExitBlock) &&
IfThen != IfElse && "Invariant from findScopes") ? static_cast
<void> (0) : __assert_fail ("(IfThen == RegionExitBlock || IfElse == RegionExitBlock) && IfThen != IfElse && \"Invariant from findScopes\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1902, __PRETTY_FUNCTION__))
1902 IfThen != IfElse && "Invariant from findScopes")(((IfThen == RegionExitBlock || IfElse == RegionExitBlock) &&
IfThen != IfElse && "Invariant from findScopes") ? static_cast
<void> (0) : __assert_fail ("(IfThen == RegionExitBlock || IfElse == RegionExitBlock) && IfThen != IfElse && \"Invariant from findScopes\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1902, __PRETTY_FUNCTION__))
;
1903 if (IfThen == RegionExitBlock) {
1904 // Swap them so that IfThen means going into it and IfElse means skipping
1905 // it.
1906 std::swap(IfThen, IfElse);
1907 }
1908 CHR_DEBUG(dbgs() << "IfThen " << IfThen->getName()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "IfThen " << IfThen->getName
() << " IfElse " << IfElse->getName() <<
"\n"; } } while (false)
1909 << " IfElse " << IfElse->getName() << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "IfThen " << IfThen->getName
() << " IfElse " << IfElse->getName() <<
"\n"; } } while (false)
;
1910 Value *Cond = BI->getCondition();
1911 BasicBlock *HotTarget = IsTrueBiased ? IfThen : IfElse;
1912 bool ConditionTrue = HotTarget == BI->getSuccessor(0);
1913 addToMergedCondition(ConditionTrue, Cond, BI, Scope, IRB,
1914 MergedCondition);
1915 // Constant-fold the branch at ClonedEntryBlock.
1916 assert(ConditionTrue == (HotTarget == BI->getSuccessor(0)) &&((ConditionTrue == (HotTarget == BI->getSuccessor(0)) &&
"The successor shouldn't change") ? static_cast<void> (
0) : __assert_fail ("ConditionTrue == (HotTarget == BI->getSuccessor(0)) && \"The successor shouldn't change\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1917, __PRETTY_FUNCTION__))
1917 "The successor shouldn't change")((ConditionTrue == (HotTarget == BI->getSuccessor(0)) &&
"The successor shouldn't change") ? static_cast<void> (
0) : __assert_fail ("ConditionTrue == (HotTarget == BI->getSuccessor(0)) && \"The successor shouldn't change\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1917, __PRETTY_FUNCTION__))
;
1918 Value *NewCondition = ConditionTrue ?
1919 ConstantInt::getTrue(F.getContext()) :
1920 ConstantInt::getFalse(F.getContext());
1921 BI->setCondition(NewCondition);
1922}
1923
1924// A helper for fixupBranchesAndSelects. Add to the combined branch condition
1925// and constant-fold a select in the hot path.
1926void CHR::fixupSelect(SelectInst *SI, CHRScope *Scope,
1927 IRBuilder<> &IRB,
1928 Value *&MergedCondition,
1929 BranchProbability &CHRBranchBias) {
1930 bool IsTrueBiased = Scope->TrueBiasedSelects.count(SI);
1931 assert((IsTrueBiased ||(((IsTrueBiased || Scope->FalseBiasedSelects.count(SI)) &&
"Must be biased") ? static_cast<void> (0) : __assert_fail
("(IsTrueBiased || Scope->FalseBiasedSelects.count(SI)) && \"Must be biased\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1932, __PRETTY_FUNCTION__))
1932 Scope->FalseBiasedSelects.count(SI)) && "Must be biased")(((IsTrueBiased || Scope->FalseBiasedSelects.count(SI)) &&
"Must be biased") ? static_cast<void> (0) : __assert_fail
("(IsTrueBiased || Scope->FalseBiasedSelects.count(SI)) && \"Must be biased\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1932, __PRETTY_FUNCTION__))
;
1933 assert(SelectBiasMap.find(SI) != SelectBiasMap.end() &&((SelectBiasMap.find(SI) != SelectBiasMap.end() && "Must be in the bias map"
) ? static_cast<void> (0) : __assert_fail ("SelectBiasMap.find(SI) != SelectBiasMap.end() && \"Must be in the bias map\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1934, __PRETTY_FUNCTION__))
1934 "Must be in the bias map")((SelectBiasMap.find(SI) != SelectBiasMap.end() && "Must be in the bias map"
) ? static_cast<void> (0) : __assert_fail ("SelectBiasMap.find(SI) != SelectBiasMap.end() && \"Must be in the bias map\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1934, __PRETTY_FUNCTION__))
;
1935 BranchProbability Bias = SelectBiasMap[SI];
1936 assert(Bias >= getCHRBiasThreshold() && "Must be highly biased")((Bias >= getCHRBiasThreshold() && "Must be highly biased"
) ? static_cast<void> (0) : __assert_fail ("Bias >= getCHRBiasThreshold() && \"Must be highly biased\""
, "/build/llvm-toolchain-snapshot-10~svn374877/lib/Transforms/Instrumentation/ControlHeightReduction.cpp"
, 1936, __PRETTY_FUNCTION__))
;
1937 // Take the min.
1938 if (CHRBranchBias > Bias)
1939 CHRBranchBias = Bias;
1940 Value *Cond = SI->getCondition();
1941 addToMergedCondition(IsTrueBiased, Cond, SI, Scope, IRB,
1942 MergedCondition);
1943 Value *NewCondition = IsTrueBiased ?
1944 ConstantInt::getTrue(F.getContext()) :
1945 ConstantInt::getFalse(F.getContext());
1946 SI->setCondition(NewCondition);
1947}
1948
1949// A helper for fixupBranch/fixupSelect. Add a branch condition to the merged
1950// condition.
1951void CHR::addToMergedCondition(bool IsTrueBiased, Value *Cond,
1952 Instruction *BranchOrSelect,
1953 CHRScope *Scope,
1954 IRBuilder<> &IRB,
1955 Value *&MergedCondition) {
1956 if (IsTrueBiased) {
1957 MergedCondition = IRB.CreateAnd(MergedCondition, Cond);
1958 } else {
1959 // If Cond is an icmp and all users of V except for BranchOrSelect is a
1960 // branch, negate the icmp predicate and swap the branch targets and avoid
1961 // inserting an Xor to negate Cond.
1962 bool Done = false;
1963 if (auto *ICmp = dyn_cast<ICmpInst>(Cond))
1964 if (negateICmpIfUsedByBranchOrSelectOnly(ICmp, BranchOrSelect, Scope)) {
1965 MergedCondition = IRB.CreateAnd(MergedCondition, Cond);
1966 Done = true;
1967 }
1968 if (!Done) {
1969 Value *Negate = IRB.CreateXor(
1970 ConstantInt::getTrue(F.getContext()), Cond);
1971 MergedCondition = IRB.CreateAnd(MergedCondition, Negate);
1972 }
1973 }
1974}
1975
1976void CHR::transformScopes(SmallVectorImpl<CHRScope *> &CHRScopes) {
1977 unsigned I = 0;
1978 DenseSet<PHINode *> TrivialPHIs;
1979 for (CHRScope *Scope : CHRScopes) {
1980 transformScopes(Scope, TrivialPHIs);
1981 CHR_DEBUG(do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { std::ostringstream oss; oss << " after transformScopes "
<< I++; dumpIR(F, oss.str().c_str(), nullptr); } } while
(false)
1982 std::ostringstream oss;do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { std::ostringstream oss; oss << " after transformScopes "
<< I++; dumpIR(F, oss.str().c_str(), nullptr); } } while
(false)
1983 oss << " after transformScopes " << I++;do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { std::ostringstream oss; oss << " after transformScopes "
<< I++; dumpIR(F, oss.str().c_str(), nullptr); } } while
(false)
1984 dumpIR(F, oss.str().c_str(), nullptr))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { std::ostringstream oss; oss << " after transformScopes "
<< I++; dumpIR(F, oss.str().c_str(), nullptr); } } while
(false)
;
1985 (void)I;
1986 }
1987}
1988
1989static void LLVM_ATTRIBUTE_UNUSED__attribute__((__unused__))
1990dumpScopes(SmallVectorImpl<CHRScope *> &Scopes, const char *Label) {
1991 dbgs() << Label << " " << Scopes.size() << "\n";
1992 for (CHRScope *Scope : Scopes) {
1993 dbgs() << *Scope << "\n";
1994 }
1995}
1996
1997bool CHR::run() {
1998 if (!shouldApply(F, PSI))
2
Assuming the condition is false
3
Taking false branch
1999 return false;
2000
2001 CHR_DEBUG(dumpIR(F, "before", nullptr))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dumpIR(F, "before", nullptr); } } while (false)
;
4
Assuming 'DebugFlag' is false
5
Loop condition is false. Exiting loop
2002
2003 bool Changed = false;
2004 {
2005 CHR_DEBUG
5.1
'DebugFlag' is false
(do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "RegionInfo:\n"; RI.print(dbgs());
} } while (false)
6
Loop condition is false. Exiting loop
2006 dbgs() << "RegionInfo:\n";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "RegionInfo:\n"; RI.print(dbgs());
} } while (false)
2007 RI.print(dbgs()))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "RegionInfo:\n"; RI.print(dbgs());
} } while (false)
;
2008
2009 // Recursively traverse the region tree and find regions that have biased
2010 // branches and/or selects and create scopes.
2011 SmallVector<CHRScope *, 8> AllScopes;
2012 findScopes(AllScopes);
2013 CHR_DEBUG(dumpScopes(AllScopes, "All scopes"))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dumpScopes(AllScopes, "All scopes"); } } while (false
)
;
7
Assuming 'DebugFlag' is false
8
Loop condition is false. Exiting loop
2014
2015 // Split the scopes if 1) the conditiona values of the biased
2016 // branches/selects of the inner/lower scope can't be hoisted up to the
2017 // outermost/uppermost scope entry, or 2) the condition values of the biased
2018 // branches/selects in a scope (including subscopes) don't share at least
2019 // one common value.
2020 SmallVector<CHRScope *, 8> SplitScopes;
2021 splitScopes(AllScopes, SplitScopes);
9
Calling 'CHR::splitScopes'
2022 CHR_DEBUG(dumpScopes(SplitScopes, "Split scopes"))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dumpScopes(SplitScopes, "Split scopes"); } } while
(false)
;
2023
2024 // After splitting, set the biased regions and selects of a scope (a tree
2025 // root) that include those of the subscopes.
2026 classifyBiasedScopes(SplitScopes);
2027 CHR_DEBUG(dbgs() << "Set per-scope bias " << SplitScopes.size() << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "Set per-scope bias " << SplitScopes
.size() << "\n"; } } while (false)
;
2028
2029 // Filter out the scopes that has only one biased region or select (CHR
2030 // isn't useful in such a case).
2031 SmallVector<CHRScope *, 8> FilteredScopes;
2032 filterScopes(SplitScopes, FilteredScopes);
2033 CHR_DEBUG(dumpScopes(FilteredScopes, "Filtered scopes"))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dumpScopes(FilteredScopes, "Filtered scopes"); } }
while (false)
;
2034
2035 // Set the regions to be CHR'ed and their hoist stops for each scope.
2036 SmallVector<CHRScope *, 8> SetScopes;
2037 setCHRRegions(FilteredScopes, SetScopes);
2038 CHR_DEBUG(dumpScopes(SetScopes, "Set CHR regions"))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dumpScopes(SetScopes, "Set CHR regions"); } } while
(false)
;
2039
2040 // Sort CHRScopes by the depth so that outer CHRScopes comes before inner
2041 // ones. We need to apply CHR from outer to inner so that we apply CHR only
2042 // to the hot path, rather than both hot and cold paths.
2043 SmallVector<CHRScope *, 8> SortedScopes;
2044 sortScopes(SetScopes, SortedScopes);
2045 CHR_DEBUG(dumpScopes(SortedScopes, "Sorted scopes"))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dumpScopes(SortedScopes, "Sorted scopes"); } } while
(false)
;
2046
2047 CHR_DEBUG(do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "RegionInfo:\n"; RI.print(dbgs());
} } while (false)
2048 dbgs() << "RegionInfo:\n";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "RegionInfo:\n"; RI.print(dbgs());
} } while (false)
2049 RI.print(dbgs()))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dbgs() << "RegionInfo:\n"; RI.print(dbgs());
} } while (false)
;
2050
2051 // Apply the CHR transformation.
2052 if (!SortedScopes.empty()) {
2053 transformScopes(SortedScopes);
2054 Changed = true;
2055 }
2056 }
2057
2058 if (Changed) {
2059 CHR_DEBUG(dumpIR(F, "after", &Stats))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("chr")) { dumpIR(F, "after", &Stats); } } while (false)
;
2060 ORE.emit([&]() {
2061 return OptimizationRemark(DEBUG_TYPE"chr", "Stats", &F)
2062 << ore::NV("Function", &F) << " "
2063 << "Reduced the number of branches in hot paths by "
2064 << ore::NV("NumBranchesDelta", Stats.NumBranchesDelta)
2065 << " (static) and "
2066 << ore::NV("WeightedNumBranchesDelta", Stats.WeightedNumBranchesDelta)
2067 << " (weighted by PGO count)";
2068 });
2069 }
2070
2071 return Changed;
2072}
2073
2074bool ControlHeightReductionLegacyPass::runOnFunction(Function &F) {
2075 BlockFrequencyInfo &BFI =
2076 getAnalysis<BlockFrequencyInfoWrapperPass>().getBFI();
2077 DominatorTree &DT = getAnalysis<DominatorTreeWrapperPass>().getDomTree();
2078 ProfileSummaryInfo &PSI =
2079 getAnalysis<ProfileSummaryInfoWrapperPass>().getPSI();
2080 RegionInfo &RI = getAnalysis<RegionInfoPass>().getRegionInfo();
2081 std::unique_ptr<OptimizationRemarkEmitter> OwnedORE =
2082 std::make_unique<OptimizationRemarkEmitter>(&F);
2083 return CHR(F, BFI, DT, PSI, RI, *OwnedORE.get()).run();
2084}
2085
2086namespace llvm {
2087
2088ControlHeightReductionPass::ControlHeightReductionPass() {
2089 parseCHRFilterFiles();
2090}
2091
2092PreservedAnalyses ControlHeightReductionPass::run(
2093 Function &F,
2094 FunctionAnalysisManager &FAM) {
2095 auto &BFI = FAM.getResult<BlockFrequencyAnalysis>(F);
2096 auto &DT = FAM.getResult<DominatorTreeAnalysis>(F);
2097 auto &MAMProxy = FAM.getResult<ModuleAnalysisManagerFunctionProxy>(F);
2098 auto &MAM = MAMProxy.getManager();
2099 auto &PSI = *MAM.getCachedResult<ProfileSummaryAnalysis>(*F.getParent());
2100 auto &RI = FAM.getResult<RegionInfoAnalysis>(F);
2101 auto &ORE = FAM.getResult<OptimizationRemarkEmitterAnalysis>(F);
2102 bool Changed = CHR(F, BFI, DT, PSI, RI, ORE).run();
1
Calling 'CHR::run'
2103 if (!Changed)
2104 return PreservedAnalyses::all();
2105 auto PA = PreservedAnalyses();
2106 PA.preserve<GlobalsAA>();
2107 return PA;
2108}
2109
2110} // namespace llvm