[FuncSpec] Replace LoopInfo with BlockFrequencyInfo.

[labrinea]

Summary

Using AvgLoopIters on any loop is too imprecise making the cost model favor users inside loop nests regardless of the actual tripcount.

Compile times -O3

benchmark	nspecs before	nspecs after	instrCnt delta %
ClamAV	5	5	+0.006
7zip			-0.031
tramp3d-v4			-0.043
kimwitu++			-0.156
sqlite3	2		-0.571
mafft			-0.029
lencod			+0.029
SPASS	2	2	-0.038
consumer-typeset			-0.045
Bullet		1	+0.055
geomean			-0.083

Compile times LTO

benchmark	nspecs before	nspecs after	instrCnt delta %
ClamAV	1		-0.159
7zip			-0.023
tramp3d-v4			-0.018
kimwitu++			+0.016
sqlite3	2	1	+0.357
mafft			+0.029
lencod			0
SPASS	1		-0.283
consumer-typeset		1	+0.539
Bullet			+0.013
geomean			+0.047

[mingmingl]

llvm/lib/Transforms/IPO/FunctionSpecialization.cpp

599–606

(Hi! I notice this and was trying to get some generated function specialized so would like to share some thoughts :) )

Function spec cost is calculated as Metrics.NumInsts * InlineConstants::getInstrCost() (i.e., without TTI per instruction cost).
I wonder if it would make more sense to make per-instruction cost calculation consistent.

Also it seems Weight could give a big bonus for functions in a hot inner-loop with PGO, wonder how it affects code size in PGO case.

[labrinea]

llvm/lib/Transforms/IPO/FunctionSpecialization.cpp

599–606

The Specialization cost estimation is wrong and I am planning to fix that in later patches. Metrics.NumInsts already contains TargetTransformInfo::TCK_CodeSize. Regarding the weight, right now it only favors basic blocks with higher frequency than the entry (in other words, loops). In future patches I want to tweak the weight calculation as <SomeConstant> x <BlockFreq> / <EntrFreq> in order to allow conditional code to be accounted for the Bonus calculation. I haven't measured PGO configurations thoroughly, but I am planning radical changes to the cost model in the near future as enabling specializations of literal constants is becoming necessity and right now is too heavy weight.

[ChuanqiXu]

Interesting. Have you measured with spec2017?

[labrinea]

In D150375#4337042, @ChuanqiXu wrote:

Interesting. Have you measured with spec2017?

Hi. I measured (without PGO) but didn't see any changes. The main drive for this change is to enable specialization of literal constants (D150649), which would otherwse trigger too often with LoopInfo.

[ChuanqiXu]

In D150375#4345226, @labrinea wrote:

In D150375#4337042, @ChuanqiXu wrote:

Interesting. Have you measured with spec2017?

Hi. I measured (without PGO) but didn't see any changes. The main drive for this change is to enable specialization of literal constants (D150649), which would otherwse trigger too often with LoopInfo.

Do you measured it with fulllto? If yes, I feel the change looks good.

[labrinea]

In D150375#4345303, @ChuanqiXu wrote:

In D150375#4345226, @labrinea wrote:

In D150375#4337042, @ChuanqiXu wrote:

Interesting. Have you measured with spec2017?

Hi. I measured (without PGO) but didn't see any changes. The main drive for this change is to enable specialization of literal constants (D150649), which would otherwse trigger too often with LoopInfo.

Do you measured it with fulllto? If yes, I feel the change looks good.

Yes, both default -O3 and full LTO pipelines as shown on the description.

[ChuanqiXu]

LGTM then. Thanks! Let's give some time for other reviewers.

[uabelho]

Hello,

The following starts crashing with this patch:

opt -passes="ipsccp,function(adce)" -mtriple=hexagon bbi-82827.ll -o /dev/null

Result:

PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace.
Stack dump:
0.	Program arguments: ../../main-github/llvm/build-all/bin/opt -passes=ipsccp,function(adce) -mtriple=hexagon bbi-82827.ll -o /dev/null
 #0 0x00005590a334c8b7 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (../../main-github/llvm/build-all/bin/opt+0x2d978b7)
 #1 0x00005590a334a5de llvm::sys::RunSignalHandlers() (../../main-github/llvm/build-all/bin/opt+0x2d955de)
 #2 0x00005590a334cf4f SignalHandler(int) Signals.cpp:0:0
 #3 0x00007f396568d630 __restore_rt sigaction.c:0:0
 #4 0x00005590a2c565a1 llvm::DebugLoc::get() const (../../main-github/llvm/build-all/bin/opt+0x26a15a1)
 #5 0x00005590a3db2f31 (anonymous namespace)::AggressiveDeadCodeElimination::markLive(llvm::Instruction*) ADCE.cpp:0:0
 #6 0x00005590a3dafca1 (anonymous namespace)::AggressiveDeadCodeElimination::performDeadCodeElimination() ADCE.cpp:0:0
 #7 0x00005590a3dae4a9 llvm::ADCEPass::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (../../main-github/llvm/build-all/bin/opt+0x37f94a9)
 #8 0x00005590a35590dd llvm::detail::PassModel<llvm::Function, llvm::ADCEPass, llvm::PreservedAnalyses, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (../../main-github/llvm/build-all/bin/opt+0x2fa40dd)
 #9 0x00005590a2d2c314 llvm::PassManager<llvm::Function, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (../../main-github/llvm/build-all/bin/opt+0x2777314)
#10 0x00005590a11e95ed llvm::detail::PassModel<llvm::Function, llvm::PassManager<llvm::Function, llvm::AnalysisManager<llvm::Function>>, llvm::PreservedAnalyses, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (../../main-github/llvm/build-all/bin/opt+0xc345ed)
#11 0x00005590a2d306fe llvm::ModuleToFunctionPassAdaptor::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (../../main-github/llvm/build-all/bin/opt+0x277b6fe)
#12 0x00005590a11e938d llvm::detail::PassModel<llvm::Module, llvm::ModuleToFunctionPassAdaptor, llvm::PreservedAnalyses, llvm::AnalysisManager<llvm::Module>>::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (../../main-github/llvm/build-all/bin/opt+0xc3438d)
#13 0x00005590a2d2b4a4 llvm::PassManager<llvm::Module, llvm::AnalysisManager<llvm::Module>>::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (../../main-github/llvm/build-all/bin/opt+0x27764a4)
#14 0x00005590a0e2314e llvm::runPassPipeline(llvm::StringRef, llvm::Module&, llvm::TargetMachine*, llvm::TargetLibraryInfoImpl*, llvm::ToolOutputFile*, llvm::ToolOutputFile*, llvm::ToolOutputFile*, llvm::StringRef, llvm::ArrayRef<llvm::PassPlugin>, llvm::opt_tool::OutputKind, llvm::opt_tool::VerifierKind, bool, bool, bool, bool, bool, bool) (../../main-github/llvm/build-all/bin/opt+0x86e14e)
#15 0x00005590a0e3181e main (../../main-github/llvm/build-all/bin/opt+0x87c81e)
#16 0x00007f3962dc0555 __libc_start_main (/lib64/libc.so.6+0x22555)
#17 0x00005590a0e1d8a0 _start (../../main-github/llvm/build-all/bin/opt+0x8688a0)
Segmentation fault (core dumped)

bbi-82827.ll4 KBDownload

[uabelho]

In D150375#4367861, @uabelho wrote:

Hello,

The following starts crashing with this patch:

opt -passes="ipsccp,function(adce)" -mtriple=hexagon bbi-82827.ll -o /dev/null

Result:

PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace.
Stack dump:
0.	Program arguments: ../../main-github/llvm/build-all/bin/opt -passes=ipsccp,function(adce) -mtriple=hexagon bbi-82827.ll -o /dev/null
 #0 0x00005590a334c8b7 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (../../main-github/llvm/build-all/bin/opt+0x2d978b7)
 #1 0x00005590a334a5de llvm::sys::RunSignalHandlers() (../../main-github/llvm/build-all/bin/opt+0x2d955de)
 #2 0x00005590a334cf4f SignalHandler(int) Signals.cpp:0:0
 #3 0x00007f396568d630 __restore_rt sigaction.c:0:0
 #4 0x00005590a2c565a1 llvm::DebugLoc::get() const (../../main-github/llvm/build-all/bin/opt+0x26a15a1)
 #5 0x00005590a3db2f31 (anonymous namespace)::AggressiveDeadCodeElimination::markLive(llvm::Instruction*) ADCE.cpp:0:0
 #6 0x00005590a3dafca1 (anonymous namespace)::AggressiveDeadCodeElimination::performDeadCodeElimination() ADCE.cpp:0:0
 #7 0x00005590a3dae4a9 llvm::ADCEPass::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (../../main-github/llvm/build-all/bin/opt+0x37f94a9)
 #8 0x00005590a35590dd llvm::detail::PassModel<llvm::Function, llvm::ADCEPass, llvm::PreservedAnalyses, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (../../main-github/llvm/build-all/bin/opt+0x2fa40dd)
 #9 0x00005590a2d2c314 llvm::PassManager<llvm::Function, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (../../main-github/llvm/build-all/bin/opt+0x2777314)
#10 0x00005590a11e95ed llvm::detail::PassModel<llvm::Function, llvm::PassManager<llvm::Function, llvm::AnalysisManager<llvm::Function>>, llvm::PreservedAnalyses, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (../../main-github/llvm/build-all/bin/opt+0xc345ed)
#11 0x00005590a2d306fe llvm::ModuleToFunctionPassAdaptor::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (../../main-github/llvm/build-all/bin/opt+0x277b6fe)
#12 0x00005590a11e938d llvm::detail::PassModel<llvm::Module, llvm::ModuleToFunctionPassAdaptor, llvm::PreservedAnalyses, llvm::AnalysisManager<llvm::Module>>::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (../../main-github/llvm/build-all/bin/opt+0xc3438d)
#13 0x00005590a2d2b4a4 llvm::PassManager<llvm::Module, llvm::AnalysisManager<llvm::Module>>::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (../../main-github/llvm/build-all/bin/opt+0x27764a4)
#14 0x00005590a0e2314e llvm::runPassPipeline(llvm::StringRef, llvm::Module&, llvm::TargetMachine*, llvm::TargetLibraryInfoImpl*, llvm::ToolOutputFile*, llvm::ToolOutputFile*, llvm::ToolOutputFile*, llvm::StringRef, llvm::ArrayRef<llvm::PassPlugin>, llvm::opt_tool::OutputKind, llvm::opt_tool::VerifierKind, bool, bool, bool, bool, bool, bool) (../../main-github/llvm/build-all/bin/opt+0x86e14e)
#15 0x00005590a0e3181e main (../../main-github/llvm/build-all/bin/opt+0x87c81e)
#16 0x00007f3962dc0555 __libc_start_main (/lib64/libc.so.6+0x22555)
#17 0x00005590a0e1d8a0 _start (../../main-github/llvm/build-all/bin/opt+0x8688a0)
Segmentation fault (core dumped)

bbi-82827.ll4 KBDownload

Ping @labrinea

Can you take a look at this regression?

[bjope]

In D150375#4371980, @uabelho wrote:

In D150375#4367861, @uabelho wrote:

Hello,

The following starts crashing with this patch:

opt -passes="ipsccp,function(adce)" -mtriple=hexagon bbi-82827.ll -o /dev/null

Result:

PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace.
Stack dump:
0.	Program arguments: ../../main-github/llvm/build-all/bin/opt -passes=ipsccp,function(adce) -mtriple=hexagon bbi-82827.ll -o /dev/null
 #0 0x00005590a334c8b7 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (../../main-github/llvm/build-all/bin/opt+0x2d978b7)
 #1 0x00005590a334a5de llvm::sys::RunSignalHandlers() (../../main-github/llvm/build-all/bin/opt+0x2d955de)
 #2 0x00005590a334cf4f SignalHandler(int) Signals.cpp:0:0
 #3 0x00007f396568d630 __restore_rt sigaction.c:0:0
 #4 0x00005590a2c565a1 llvm::DebugLoc::get() const (../../main-github/llvm/build-all/bin/opt+0x26a15a1)
 #5 0x00005590a3db2f31 (anonymous namespace)::AggressiveDeadCodeElimination::markLive(llvm::Instruction*) ADCE.cpp:0:0
 #6 0x00005590a3dafca1 (anonymous namespace)::AggressiveDeadCodeElimination::performDeadCodeElimination() ADCE.cpp:0:0
 #7 0x00005590a3dae4a9 llvm::ADCEPass::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (../../main-github/llvm/build-all/bin/opt+0x37f94a9)
 #8 0x00005590a35590dd llvm::detail::PassModel<llvm::Function, llvm::ADCEPass, llvm::PreservedAnalyses, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (../../main-github/llvm/build-all/bin/opt+0x2fa40dd)
 #9 0x00005590a2d2c314 llvm::PassManager<llvm::Function, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (../../main-github/llvm/build-all/bin/opt+0x2777314)
#10 0x00005590a11e95ed llvm::detail::PassModel<llvm::Function, llvm::PassManager<llvm::Function, llvm::AnalysisManager<llvm::Function>>, llvm::PreservedAnalyses, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (../../main-github/llvm/build-all/bin/opt+0xc345ed)
#11 0x00005590a2d306fe llvm::ModuleToFunctionPassAdaptor::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (../../main-github/llvm/build-all/bin/opt+0x277b6fe)
#12 0x00005590a11e938d llvm::detail::PassModel<llvm::Module, llvm::ModuleToFunctionPassAdaptor, llvm::PreservedAnalyses, llvm::AnalysisManager<llvm::Module>>::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (../../main-github/llvm/build-all/bin/opt+0xc3438d)
#13 0x00005590a2d2b4a4 llvm::PassManager<llvm::Module, llvm::AnalysisManager<llvm::Module>>::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (../../main-github/llvm/build-all/bin/opt+0x27764a4)
#14 0x00005590a0e2314e llvm::runPassPipeline(llvm::StringRef, llvm::Module&, llvm::TargetMachine*, llvm::TargetLibraryInfoImpl*, llvm::ToolOutputFile*, llvm::ToolOutputFile*, llvm::ToolOutputFile*, llvm::StringRef, llvm::ArrayRef<llvm::PassPlugin>, llvm::opt_tool::OutputKind, llvm::opt_tool::VerifierKind, bool, bool, bool, bool, bool, bool) (../../main-github/llvm/build-all/bin/opt+0x86e14e)
#15 0x00005590a0e3181e main (../../main-github/llvm/build-all/bin/opt+0x87c81e)
#16 0x00007f3962dc0555 __libc_start_main (/lib64/libc.so.6+0x22555)
#17 0x00005590a0e1d8a0 _start (../../main-github/llvm/build-all/bin/opt+0x8688a0)
Segmentation fault (core dumped)

bbi-82827.ll4 KBDownload

Ping @labrinea

Can you take a look at this regression?

It also crashes when using opt -passes="ipsccp,print<postdomtree>" -mtriple=hexagon bbi-82827.ll -o /dev/null.
So it is something with the PostDominatorTree analysis getting messed up?

[uabelho]

Both valgrind and ASan complains about memory problems. ASan says there is heap-use-after-free for stuff freed here

#1 0x47b6bd9 in llvm::DomTreeUpdater::forceFlushDeletedBB()
#2 0x47b649c in tryFlushDeletedBB
#3 0x47b649c in llvm::DomTreeUpdater::dropOutOfDateUpdates()
#4 0x174687e in llvm::DomTreeUpdater::~DomTreeUpdater()
#5 0x8111719 in runIPSCCP(llvm::Module&, llvm::DataLayout const&, llvm::AnalysisManager<llvm::Function>*, std::__1::function<llvm::BlockFrequencyInfo& (llvm::Function&)>, std::__1::function<llvm::TargetLibraryInfo const& (llvm::Function&)>, std::__1::function<llvm::TargetTransformInfo& (llvm::Function&)>, std::__1::function<llvm::AssumptionCache& (llvm::Function&)>, llvm::function_ref<llvm::AnalysisResultsForFn (llvm::Function&)>, bool)

I've also seen crashes for other passes than adce, e.g. gvnhoist.

[bjope]

In D150375#4375324, @bjope wrote:

In D150375#4371980, @uabelho wrote:

In D150375#4367861, @uabelho wrote:

Hello,

The following starts crashing with this patch:

opt -passes="ipsccp,function(adce)" -mtriple=hexagon bbi-82827.ll -o /dev/null

Result:

PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace.
Stack dump:
0.	Program arguments: ../../main-github/llvm/build-all/bin/opt -passes=ipsccp,function(adce) -mtriple=hexagon bbi-82827.ll -o /dev/null
 #0 0x00005590a334c8b7 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (../../main-github/llvm/build-all/bin/opt+0x2d978b7)
 #1 0x00005590a334a5de llvm::sys::RunSignalHandlers() (../../main-github/llvm/build-all/bin/opt+0x2d955de)
 #2 0x00005590a334cf4f SignalHandler(int) Signals.cpp:0:0
 #3 0x00007f396568d630 __restore_rt sigaction.c:0:0
 #4 0x00005590a2c565a1 llvm::DebugLoc::get() const (../../main-github/llvm/build-all/bin/opt+0x26a15a1)
 #5 0x00005590a3db2f31 (anonymous namespace)::AggressiveDeadCodeElimination::markLive(llvm::Instruction*) ADCE.cpp:0:0
 #6 0x00005590a3dafca1 (anonymous namespace)::AggressiveDeadCodeElimination::performDeadCodeElimination() ADCE.cpp:0:0
 #7 0x00005590a3dae4a9 llvm::ADCEPass::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (../../main-github/llvm/build-all/bin/opt+0x37f94a9)
 #8 0x00005590a35590dd llvm::detail::PassModel<llvm::Function, llvm::ADCEPass, llvm::PreservedAnalyses, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (../../main-github/llvm/build-all/bin/opt+0x2fa40dd)
 #9 0x00005590a2d2c314 llvm::PassManager<llvm::Function, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (../../main-github/llvm/build-all/bin/opt+0x2777314)
#10 0x00005590a11e95ed llvm::detail::PassModel<llvm::Function, llvm::PassManager<llvm::Function, llvm::AnalysisManager<llvm::Function>>, llvm::PreservedAnalyses, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (../../main-github/llvm/build-all/bin/opt+0xc345ed)
#11 0x00005590a2d306fe llvm::ModuleToFunctionPassAdaptor::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (../../main-github/llvm/build-all/bin/opt+0x277b6fe)
#12 0x00005590a11e938d llvm::detail::PassModel<llvm::Module, llvm::ModuleToFunctionPassAdaptor, llvm::PreservedAnalyses, llvm::AnalysisManager<llvm::Module>>::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (../../main-github/llvm/build-all/bin/opt+0xc3438d)
#13 0x00005590a2d2b4a4 llvm::PassManager<llvm::Module, llvm::AnalysisManager<llvm::Module>>::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (../../main-github/llvm/build-all/bin/opt+0x27764a4)
#14 0x00005590a0e2314e llvm::runPassPipeline(llvm::StringRef, llvm::Module&, llvm::TargetMachine*, llvm::TargetLibraryInfoImpl*, llvm::ToolOutputFile*, llvm::ToolOutputFile*, llvm::ToolOutputFile*, llvm::StringRef, llvm::ArrayRef<llvm::PassPlugin>, llvm::opt_tool::OutputKind, llvm::opt_tool::VerifierKind, bool, bool, bool, bool, bool, bool) (../../main-github/llvm/build-all/bin/opt+0x86e14e)
#15 0x00005590a0e3181e main (../../main-github/llvm/build-all/bin/opt+0x87c81e)
#16 0x00007f3962dc0555 __libc_start_main (/lib64/libc.so.6+0x22555)
#17 0x00005590a0e1d8a0 _start (../../main-github/llvm/build-all/bin/opt+0x8688a0)
Segmentation fault (core dumped)

bbi-82827.ll4 KBDownload

Ping @labrinea

Can you take a look at this regression?

It also crashes when using opt -passes="ipsccp,print<postdomtree>" -mtriple=hexagon bbi-82827.ll -o /dev/null.
So it is something with the PostDominatorTree analysis getting messed up?

@aeubanks / @asbirlea : Can you see any obvious mistake here, when it comes to new-PM and analysis passes?

PostDominatorTreeAnalysis is preserved (regardless of changes). There is a FAM.getCachedResult<PostDominatorTreeAnalysis>(F) that might happen if getAnalysis is called(?). But I think the new thing here is that when using BlockFrequencyAnalysis that will run the PostDominatorTreeAnalysis (via BranchProbabilityAnalysis) even if it isn't cached already.

A workaround(?) might be to comment out PA.preserve<PostDominatorTreeAnalysis>(). But I'm not sure it solve the problem completely (the given repoducer no longer crashes at least).

[bjope]

Maybe this is what is needed:

diff --git a/llvm/lib/Transforms/IPO/SCCP.cpp b/llvm/lib/Transforms/IPO/SCCP.cpp
index 21b89ce4de40..e5a940f83311 100644
--- a/llvm/lib/Transforms/IPO/SCCP.cpp
+++ b/llvm/lib/Transforms/IPO/SCCP.cpp
@@ -394,9 +394,10 @@ PreservedAnalyses IPSCCPPass::run(Module &M, ModuleAnalysisManager &AM) {
   };
   auto getAnalysis = [&FAM](Function &F) -> AnalysisResultsForFn {
     DominatorTree &DT = FAM.getResult<DominatorTreeAnalysis>(F);
+    PostDominatorTree &PDT = FAM.getResult<PostDominatorTreeAnalysis>(F);
     return {
         std::make_unique<PredicateInfo>(F, DT, FAM.getResult<AssumptionAnalysis>(F)),
-        &DT, FAM.getCachedResult<PostDominatorTreeAnalysis>(F) };
+        &DT, &PDT };
   };
 
   if (!runIPSCCP(M, DL, &FAM, GetBFI, GetTLI, GetTTI, GetAC, getAnalysis,

By providing a mutable PDT, IPSCCP+solver would end up updating the PDT when doing changes?

[labrinea]

Sorry, I didn't get any notification for this regression. I'll investigate.

[bjope]

So to summarize what I think is going on (more or less by just looking at the code, I haven't been running it in a debugger):

1. When setting up the DomTreeUpdater the use of FAM.getCachedResult<PostDominatorTreeAnalysis>(F) might result in not finding any cached PDT. So the DomTreeUpdater will not update PDT.
2. Later as a side-effect of using BlockFrequencyAnalysis, a PDT is created and calculated.
3. Optimizations are done, without updating the now existing PDT.
4. The pass says that PDT is preserved. But it has not been updated.

[bjope]

Beware: The reproducer provided by uabelho is reduced, but it is a bit ugly. I spent some time trying to clean it up, but even when using valgrind/asan it is hard to get a nice and small reproducer (e.g. that would show an incorrect PDT when using print<postdomtree>). I even ended up in a situation when renaming the labels used in the IR suddenly made the reproducer no longer crashing. So the reproducer seem to be a bit sensitive to how things end up in memory(?).

[aeubanks]

In D150375#4376283, @bjope wrote:

So to summarize what I think is going on (more or less by just looking at the code, I haven't been running it in a debugger):

1. When setting up the DomTreeUpdater the use of FAM.getCachedResult<PostDominatorTreeAnalysis>(F) might result in not finding any cached PDT. So the DomTreeUpdater will not update PDT.
2. Later as a side-effect of using BlockFrequencyAnalysis, a PDT is created and calculated.
3. Optimizations are done, without updating the now existing PDT.
4. The pass says that PDT is preserved. But it has not been updated.

sounds likely to me

writing a StandardInstrumentations instrumentation that checks if cached analyses like (Post)DomTree, MSAA, etc are still valid after a function pass would be cool and would probably catch this more easily (assuming PDT.verify() would complain here)

[bjope]

No idea why phabricator thinks that D151648 is a reverting change. It is a proposed fix, not a revert.

llvm/include/llvm/Transforms/IPO/FunctionSpecialization.h

 // - 2021 LLVM Dev Mtg “Introducing function specialisation, and can we enable
 //   it by default?”, https://www.youtube.com/watch?v=zJiCjeXgV5Q
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef LLVM_TRANSFORMS_IPO_FUNCTIONSPECIALIZATION_H
 #define LLVM_TRANSFORMS_IPO_FUNCTIONSPECIALIZATION_H
 
+#include "llvm/Analysis/BlockFrequencyInfo.h"
 #include "llvm/Analysis/CodeMetrics.h"
 #include "llvm/Analysis/InlineCost.h"
-#include "llvm/Analysis/LoopInfo.h"
 #include "llvm/Analysis/TargetTransformInfo.h"
 #include "llvm/Transforms/Scalar/SCCP.h"
 #include "llvm/Transforms/Utils/Cloning.h"
 #include "llvm/Transforms/Utils/SCCPSolver.h"
 #include "llvm/Transforms/Utils/SizeOpts.h"
 
 using namespace llvm;
 
class FunctionSpecializer {
   SCCPSolver &Solver;
 
   Module &M;
 
   /// Analysis manager, needed to invalidate analyses.
   FunctionAnalysisManager *FAM;
 
   /// Analyses used to help determine if a function should be specialized.
+  std::function<BlockFrequencyInfo &(Function &)> GetBFI;
   std::function<const TargetLibraryInfo &(Function &)> GetTLI;
   std::function<TargetTransformInfo &(Function &)> GetTTI;
   std::function<AssumptionCache &(Function &)> GetAC;
 
   SmallPtrSet<Function *, 32> Specializations;
   SmallPtrSet<Function *, 32> FullySpecialized;
   DenseMap<Function *, CodeMetrics> FunctionMetrics;
 
 public:
   FunctionSpecializer(
       SCCPSolver &Solver, Module &M, FunctionAnalysisManager *FAM,
+      std::function<BlockFrequencyInfo &(Function &)> GetBFI,
       std::function<const TargetLibraryInfo &(Function &)> GetTLI,
       std::function<TargetTransformInfo &(Function &)> GetTTI,
       std::function<AssumptionCache &(Function &)> GetAC)
-      : Solver(Solver), M(M), FAM(FAM), GetTLI(GetTLI), GetTTI(GetTTI),
-        GetAC(GetAC) {}
+      : Solver(Solver), M(M), FAM(FAM), GetBFI(GetBFI), GetTLI(GetTLI),
+        GetTTI(GetTTI), GetAC(GetAC) {}
 
   ~FunctionSpecializer();
 
   bool isClonedFunction(Function *F) { return Specializations.count(F); }
 
   bool run();
 
 private:
private:
   /// @param S Which specialization to create
   /// @return The new, cloned function
   Function *createSpecialization(Function *F, const SpecSig &S);
 
   /// Compute and return the cost of specializing function \p F.
   Cost getSpecializationCost(Function *F);
 
   /// Compute a bonus for replacing argument \p A with constant \p C.
-  Cost getSpecializationBonus(Argument *A, Constant *C, const LoopInfo &LI);
+  Cost getSpecializationBonus(Argument *A, Constant *C);
 
   /// Determine if it is possible to specialise the function for constant values
   /// of the formal parameter \p A.
   bool isArgumentInteresting(Argument *A);
 
   /// Check if the value \p V  (an actual argument) is a constant or can only
   /// have a constant value. Return that constant.
   Constant *getCandidateConstant(Value *V);

llvm/include/llvm/Transforms/Utils/SCCPSolver.h

 class Value;
 class ValueLatticeElement;
 
 /// Helper struct for bundling up the analysis results per function for IPSCCP.
 struct AnalysisResultsForFn {
   std::unique_ptr<PredicateInfo> PredInfo;
   DominatorTree *DT;
   PostDominatorTree *PDT;
-  LoopInfo *LI;
 };
 
 /// Helper struct shared between Function Specialization and SCCP Solver.
 struct ArgInfo {
   Argument *Formal; // The Formal argument being analysed.
   Constant *Actual; // A corresponding actual constant argument.
 
   ArgInfo(Argument *F, Constant *A) : Formal(F), Actual(A) {}
public:
 
   /// markBlockExecutable - This method can be used by clients to mark all of
   /// the blocks that are known to be intrinsically live in the processed unit.
   /// This returns true if the block was not considered live before.
   bool markBlockExecutable(BasicBlock *BB);
 
   const PredicateBase *getPredicateInfoFor(Instruction *I);
 
-  const LoopInfo &getLoopInfo(Function &F);
-
   DomTreeUpdater getDTU(Function &F);
 
   /// trackValueOfGlobalVariable - Clients can use this method to
   /// inform the SCCPSolver that it should track loads and stores to the
   /// specified global variable if it can.  This is only legal to call if
   /// performing Interprocedural SCCP.
   void trackValueOfGlobalVariable(GlobalVariable *GV);
 

llvm/lib/Transforms/IPO/FunctionSpecialization.cpp

 //   it by default?”, https://www.youtube.com/watch?v=zJiCjeXgV5Q
 //
 //===----------------------------------------------------------------------===//
 
 #include "llvm/Transforms/IPO/FunctionSpecialization.h"
 #include "llvm/ADT/Statistic.h"
 #include "llvm/Analysis/CodeMetrics.h"
 #include "llvm/Analysis/InlineCost.h"
-#include "llvm/Analysis/LoopInfo.h"
 #include "llvm/Analysis/TargetTransformInfo.h"
 #include "llvm/Analysis/ValueLattice.h"
 #include "llvm/Analysis/ValueLatticeUtils.h"
 #include "llvm/Analysis/ValueTracking.h"
 #include "llvm/IR/IntrinsicInst.h"
 #include "llvm/Transforms/Scalar/SCCP.h"
 #include "llvm/Transforms/Utils/Cloning.h"
 #include "llvm/Transforms/Utils/SCCPSolver.h"
static cl::opt<unsigned> MaxClones(
     "The maximum number of clones allowed for a single function "
     "specialization"));
 
 static cl::opt<unsigned> MinFunctionSize(
     "funcspec-min-function-size", cl::init(100), cl::Hidden, cl::desc(
     "Don't specialize functions that have less than this number of "
     "instructions"));
 
-static cl::opt<unsigned> AvgLoopIters(
-    "funcspec-avg-loop-iters", cl::init(10), cl::Hidden, cl::desc(
-    "Average loop iteration count"));
-
 static cl::opt<bool> SpecializeOnAddress(
     "funcspec-on-address", cl::init(false), cl::Hidden, cl::desc(
     "Enable function specialization on the address of global values"));
 
 // Disabled by default as it can significantly increase compilation times.
 //
 // https://llvm-compile-time-tracker.com
 // https://github.com/nikic/llvm-compile-time-tracker
if (auto It = UniqueSpecs.find(S); It != UniqueSpecs.end()) {
       if (CS.getFunction() == F)
         continue;
       const unsigned Index = It->second;
       AllSpecs[Index].CallSites.push_back(&CS);
     } else {
       // Calculate the specialisation gain.
       Cost Score = 0 - SpecCost;
       for (ArgInfo &A : S.Args)
-        Score +=
-            getSpecializationBonus(A.Formal, A.Actual, Solver.getLoopInfo(*F));
+        Score += getSpecializationBonus(A.Formal, A.Actual);
 
       // Discard unprofitable specialisations.
       if (!ForceSpecialization && Score <= 0)
         continue;
 
       // Create a new specialisation entry.
       auto &Spec = AllSpecs.emplace_back(F, S, Score);
       if (CS.getFunction() != F)
if (Metrics.notDuplicatable || !Metrics.NumInsts.isValid() ||
     return InstructionCost::getInvalid();
 
   // Otherwise, set the specialization cost to be the cost of all the
   // instructions in the function.
   return Metrics.NumInsts * InlineConstants::getInstrCost();
 }
 
 static Cost getUserBonus(User *U, TargetTransformInfo &TTI,
-                         const LoopInfo &LI) {
+                         BlockFrequencyInfo &BFI) {
   auto *I = dyn_cast_or_null<Instruction>(U);
   // If not an instruction we do not know how to evaluate.
   // Keep minimum possible cost for now so that it doesnt affect
   // specialization.
   if (!I)
-    return std::numeric_limits<unsigned>::min();
+    return 0;
 
-  Cost Bonus =
-      TTI.getInstructionCost(U, TargetTransformInfo::TCK_SizeAndLatency);
+  uint64_t Weight = BFI.getBlockFreq(I->getParent()).getFrequency() /
+                    BFI.getEntryFreq();
+  if (!Weight)
+    return 0;
 
-  // Increase the cost if it is inside the loop.
-  unsigned LoopDepth = LI.getLoopDepth(I->getParent());
-  Bonus *= std::pow((double)AvgLoopIters, LoopDepth);
+  Cost Bonus = Weight *
+      TTI.getInstructionCost(U, TargetTransformInfo::TCK_SizeAndLatency);
 
   // Traverse recursively if there are more uses.
   // TODO: Any other instructions to be added here?
   if (I->mayReadFromMemory() || I->isCast())
     for (auto *User : I->users())
-      Bonus += getUserBonus(User, TTI, LI);
+      Bonus += getUserBonus(User, TTI, BFI);
 
   return Bonus;
 }
 
 /// Compute a bonus for replacing argument \p A with constant \p C.
-Cost FunctionSpecializer::getSpecializationBonus(Argument *A, Constant *C,
-                                                 const LoopInfo &LI) {
+Cost FunctionSpecializer::getSpecializationBonus(Argument *A, Constant *C) {
   Function *F = A->getParent();
   auto &TTI = (GetTTI)(*F);
+  auto &BFI = (GetBFI)(*F);
   LLVM_DEBUG(dbgs() << "FnSpecialization: Analysing bonus for constant: "
                     << C->getNameOrAsOperand() << "\n");
 
   Cost TotalCost = 0;
   for (auto *U : A->users()) {
-    TotalCost += getUserBonus(U, TTI, LI);
+    TotalCost += getUserBonus(U, TTI, BFI);
     LLVM_DEBUG(dbgs() << "FnSpecialization:   User cost ";
                TotalCost.print(dbgs()); dbgs() << " for: " << *U << "\n");
   }
 
   // The below heuristic is only concerned with exposing inlining
   // opportunities via indirect call promotion. If the argument is not a
   // (potentially casted) function pointer, give up.
   Function *CalledFunction = dyn_cast<Function>(C->stripPointerCasts());

llvm/lib/Transforms/IPO/SCCP.cpp

 //===-- SCCP.cpp ----------------------------------------------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 //
 // This file implements Interprocedural Sparse Conditional Constant Propagation.
 //
 //===----------------------------------------------------------------------===//
 
 #include "llvm/Transforms/IPO/SCCP.h"
 #include "llvm/ADT/SetVector.h"
 #include "llvm/Analysis/AssumptionCache.h"
-#include "llvm/Analysis/LoopInfo.h"
+#include "llvm/Analysis/BlockFrequencyInfo.h"
 #include "llvm/Analysis/PostDominators.h"
 #include "llvm/Analysis/TargetLibraryInfo.h"
 #include "llvm/Analysis/TargetTransformInfo.h"
 #include "llvm/Analysis/ValueLattice.h"
 #include "llvm/Analysis/ValueLatticeUtils.h"
 #include "llvm/Analysis/ValueTracking.h"
 #include "llvm/IR/Constants.h"
 #include "llvm/IR/IntrinsicInst.h"
for (BasicBlock &BB : F) {
     if (auto *RI = dyn_cast<ReturnInst>(BB.getTerminator()))
       if (!isa<UndefValue>(RI->getOperand(0)))
         ReturnsToZap.push_back(RI);
   }
 }
 
 static bool runIPSCCP(
     Module &M, const DataLayout &DL, FunctionAnalysisManager *FAM,
+    std::function<BlockFrequencyInfo &(Function &)> GetBFI,
     std::function<const TargetLibraryInfo &(Function &)> GetTLI,
     std::function<TargetTransformInfo &(Function &)> GetTTI,
     std::function<AssumptionCache &(Function &)> GetAC,
     function_ref<AnalysisResultsForFn(Function &)> getAnalysis,
     bool IsFuncSpecEnabled) {
   SCCPSolver Solver(DL, GetTLI, M.getContext());
-  FunctionSpecializer Specializer(Solver, M, FAM, GetTLI, GetTTI, GetAC);
+  FunctionSpecializer Specializer(Solver, M, FAM, GetBFI, GetTLI, GetTTI,
+                                  GetAC);
 
   // Loop over all functions, marking arguments to those with their addresses
   // taken or that are external as overdefined.
   for (Function &F : M) {
     if (F.isDeclaration())
       continue;
 
     Solver.addAnalysis(F, getAnalysis(F));

 }
 
 PreservedAnalyses IPSCCPPass::run(Module &M, ModuleAnalysisManager &AM) {
   const DataLayout &DL = M.getDataLayout();
   auto &FAM = AM.getResult<FunctionAnalysisManagerModuleProxy>(M).getManager();
   auto GetTLI = [&FAM](Function &F) -> const TargetLibraryInfo & {
     return FAM.getResult<TargetLibraryAnalysis>(F);
   };
+  auto GetBFI = [&](Function &F) -> BlockFrequencyInfo & {
+    return FAM.getResult<BlockFrequencyAnalysis>(F);
+  };
   auto GetTTI = [&FAM](Function &F) -> TargetTransformInfo & {
     return FAM.getResult<TargetIRAnalysis>(F);
   };
   auto GetAC = [&FAM](Function &F) -> AssumptionCache & {
     return FAM.getResult<AssumptionAnalysis>(F);
   };
   auto getAnalysis = [&FAM, this](Function &F) -> AnalysisResultsForFn {
     DominatorTree &DT = FAM.getResult<DominatorTreeAnalysis>(F);
     return {
         std::make_unique<PredicateInfo>(F, DT, FAM.getResult<AssumptionAnalysis>(F)),
-        &DT, FAM.getCachedResult<PostDominatorTreeAnalysis>(F),
-        isFuncSpecEnabled() ? &FAM.getResult<LoopAnalysis>(F) : nullptr };
+        &DT, FAM.getCachedResult<PostDominatorTreeAnalysis>(F) };
   };
 
-  if (!runIPSCCP(M, DL, &FAM, GetTLI, GetTTI, GetAC, getAnalysis,
+  if (!runIPSCCP(M, DL, &FAM, GetBFI, GetTLI, GetTTI, GetAC, getAnalysis,
                  isFuncSpecEnabled()))
     return PreservedAnalyses::all();
 
   PreservedAnalyses PA;
   PA.preserve<DominatorTreeAnalysis>();
   PA.preserve<PostDominatorTreeAnalysis>();
   PA.preserve<FunctionAnalysisManagerModuleProxy>();
   return PA;
 }

llvm/lib/Transforms/Utils/SCCPSolver.cpp

public:
 
   const PredicateBase *getPredicateInfoFor(Instruction *I) {
     auto A = AnalysisResults.find(I->getParent()->getParent());
     if (A == AnalysisResults.end())
       return nullptr;
     return A->second.PredInfo->getPredicateInfoFor(I);
   }
 
-  const LoopInfo &getLoopInfo(Function &F) {
-    auto A = AnalysisResults.find(&F);
-    assert(A != AnalysisResults.end() && A->second.LI &&
-           "Need LoopInfo analysis results for function.");
-    return *A->second.LI;
-  }
-
   DomTreeUpdater getDTU(Function &F) {
     auto A = AnalysisResults.find(&F);
     assert(A != AnalysisResults.end() && "Need analysis results for function.");
     return {A->second.DT, A->second.PDT, DomTreeUpdater::UpdateStrategy::Lazy};
   }
 
   SCCPInstVisitor(const DataLayout &DL,
                   std::function<const TargetLibraryInfo &(Function &)> GetTLI,

 bool SCCPSolver::markBlockExecutable(BasicBlock *BB) {
   return Visitor->markBlockExecutable(BB);
 }
 
 const PredicateBase *SCCPSolver::getPredicateInfoFor(Instruction *I) {
   return Visitor->getPredicateInfoFor(I);
 }
 
-const LoopInfo &SCCPSolver::getLoopInfo(Function &F) {
-  return Visitor->getLoopInfo(F);
-}
-
 DomTreeUpdater SCCPSolver::getDTU(Function &F) { return Visitor->getDTU(F); }
 
 void SCCPSolver::trackValueOfGlobalVariable(GlobalVariable *GV) {
   Visitor->trackValueOfGlobalVariable(GV);
 }
 
 void SCCPSolver::addTrackedFunction(Function *F) {
   Visitor->addTrackedFunction(F);

llvm/test/Other/new-pm-defaults.ll

 ; The IR below was crafted so as:
 ; 1) To have a loop, so we create a loop pass manager
 ; 2) To be "immutable" in the sense that no pass in the standard
 ;    pipeline will modify it.
 ; Since no transformations take place, we don't expect any analyses
 ; to be invalidated.
 ; Any invalidation that shows up here is a bug, unless we started modifying
 ; the IR, in which case we need to make it immutable harder.
 
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes='default<O1>' -S %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-FUNC-SPEC,CHECK-O1,%llvmcheckext
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-O1,%llvmcheckext
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes='default<O2>' -S  %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-FUNC-SPEC,CHECK-O2,CHECK-O23SZ,%llvmcheckext
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-O2,CHECK-O23SZ,%llvmcheckext
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes='default<O3>' -S  %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-FUNC-SPEC,CHECK-O3,CHECK-O23SZ,%llvmcheckext
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-O3,CHECK-O23SZ,%llvmcheckext
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes='default<Os>' -S %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-NO-FUNC-SPEC,CHECK-Os,CHECK-O23SZ,%llvmcheckext
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-Os,CHECK-O23SZ,%llvmcheckext
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes='default<Oz>' -S %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-NO-FUNC-SPEC,CHECK-Oz,CHECK-O23SZ,%llvmcheckext
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-Oz,CHECK-O23SZ,%llvmcheckext
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes='lto-pre-link<O2>' -S %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-LTO,CHECK-NO-FUNC-SPEC,CHECK-O2,CHECK-O23SZ,%llvmcheckext
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-LTO,CHECK-O2,CHECK-O23SZ,%llvmcheckext
 
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes-ep-peephole='no-op-function' \
 ; RUN:     -passes='default<O3>' -S  %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-FUNC-SPEC,CHECK-O3,%llvmcheckext,CHECK-EP-PEEPHOLE,CHECK-O23SZ
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-O3,%llvmcheckext,CHECK-EP-PEEPHOLE,CHECK-O23SZ
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes-ep-late-loop-optimizations='no-op-loop' \
 ; RUN:     -passes='default<O3>' -S  %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-FUNC-SPEC,CHECK-O3,%llvmcheckext,CHECK-EP-LOOP-LATE,CHECK-O23SZ
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-O3,%llvmcheckext,CHECK-EP-LOOP-LATE,CHECK-O23SZ
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes-ep-loop-optimizer-end='no-op-loop' \
 ; RUN:     -passes='default<O3>' -S  %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-FUNC-SPEC,CHECK-O3,%llvmcheckext,CHECK-EP-LOOP-END,CHECK-O23SZ
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-O3,%llvmcheckext,CHECK-EP-LOOP-END,CHECK-O23SZ
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes-ep-scalar-optimizer-late='no-op-function' \
 ; RUN:     -passes='default<O3>' -S  %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-FUNC-SPEC,CHECK-O3,%llvmcheckext,CHECK-EP-SCALAR-LATE,CHECK-O23SZ
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-O3,%llvmcheckext,CHECK-EP-SCALAR-LATE,CHECK-O23SZ
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes-ep-cgscc-optimizer-late='no-op-cgscc' \
 ; RUN:     -passes='default<O3>' -S  %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-FUNC-SPEC,CHECK-O3,%llvmcheckext,CHECK-EP-CGSCC-LATE,CHECK-O23SZ
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-O3,%llvmcheckext,CHECK-EP-CGSCC-LATE,CHECK-O23SZ
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes-ep-vectorizer-start='no-op-function' \
 ; RUN:     -passes='default<O3>' -S  %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-FUNC-SPEC,CHECK-O3,%llvmcheckext,CHECK-EP-VECTORIZER-START,CHECK-O23SZ
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-O3,%llvmcheckext,CHECK-EP-VECTORIZER-START,CHECK-O23SZ
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes-ep-pipeline-start='no-op-module' \
 ; RUN:     -passes='default<O3>' -S  %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-FUNC-SPEC,CHECK-O3,%llvmcheckext,CHECK-EP-PIPELINE-START,CHECK-O23SZ
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-O3,%llvmcheckext,CHECK-EP-PIPELINE-START,CHECK-O23SZ
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes-ep-pipeline-early-simplification='no-op-module' \
 ; RUN:     -passes='default<O3>' -S  %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-FUNC-SPEC,CHECK-O3,%llvmcheckext,CHECK-EP-PIPELINE-EARLY-SIMPLIFICATION,CHECK-O23SZ
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-O3,%llvmcheckext,CHECK-EP-PIPELINE-EARLY-SIMPLIFICATION,CHECK-O23SZ
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes-ep-pipeline-start='no-op-module' \
 ; RUN:     -passes='lto-pre-link<O3>' -S  %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-LTO,CHECK-NO-FUNC-SPEC,CHECK-O3,%llvmcheckext,CHECK-EP-PIPELINE-START,CHECK-O23SZ
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-LTO,CHECK-O3,%llvmcheckext,CHECK-EP-PIPELINE-START,CHECK-O23SZ
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes-ep-optimizer-early='no-op-module' \
 ; RUN:     -passes='default<O3>' -S  %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-FUNC-SPEC,CHECK-O3,%llvmcheckext,CHECK-EP-OPTIMIZER-EARLY,CHECK-O23SZ
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-O3,%llvmcheckext,CHECK-EP-OPTIMIZER-EARLY,CHECK-O23SZ
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes-ep-optimizer-last='no-op-module' \
 ; RUN:     -passes='default<O3>' -S  %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-FUNC-SPEC,CHECK-O3,%llvmcheckext,CHECK-EP-OPTIMIZER-LAST,CHECK-O23SZ
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-O3,%llvmcheckext,CHECK-EP-OPTIMIZER-LAST,CHECK-O23SZ
 
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes='default<O3>' -enable-matrix -S  %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-FUNC-SPEC,CHECK-O3,CHECK-O23SZ,%llvmcheckext,CHECK-MATRIX
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-O3,CHECK-O23SZ,%llvmcheckext,CHECK-MATRIX
 
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes='default<O3>' -enable-merge-functions -S  %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-FUNC-SPEC,CHECK-O3,CHECK-O23SZ,%llvmcheckext,CHECK-MERGE-FUNCS
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-O3,CHECK-O23SZ,%llvmcheckext,CHECK-MERGE-FUNCS
 
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes='default<O3>' -ir-outliner -S  %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-FUNC-SPEC,CHECK-O3,CHECK-O23SZ,%llvmcheckext,CHECK-IR-OUTLINER
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-O3,CHECK-O23SZ,%llvmcheckext,CHECK-IR-OUTLINER
 
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes='default<O3>' -hot-cold-split -S  %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-FUNC-SPEC,CHECK-O3,CHECK-O23SZ,%llvmcheckext,CHECK-HOT-COLD-SPLIT
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-DEFAULT,CHECK-O3,CHECK-O23SZ,%llvmcheckext,CHECK-HOT-COLD-SPLIT
 
 ; Suppress FileCheck --allow-unused-prefixes=false diagnostics.
 ; CHECK-Oz: {{^}}
 
 ; CHECK-O: Running pass: Annotation2Metadata
 ; CHECK-O-NEXT: Running pass: ForceFunctionAttrsPass
 ; CHECK-EP-PIPELINE-START-NEXT: Running pass: NoOpModulePass
 ; CHECK-O-NEXT: Running pass: InferFunctionAttrsPass
 ; CHECK-O-NEXT: Running analysis: InnerAnalysisManagerProxy
 ; CHECK-O-NEXT: Running analysis: TargetLibraryAnalysis
 ; CHECK-O-NEXT: Running pass: CoroEarlyPass
 ; CHECK-O-NEXT: Running pass: LowerExpectIntrinsicPass
 ; CHECK-O-NEXT: Running pass: SimplifyCFGPass
 ; CHECK-O-NEXT: Running analysis: TargetIRAnalysis
 ; CHECK-O-NEXT: Running analysis: AssumptionAnalysis
 ; CHECK-O-NEXT: Running pass: SROAPass
 ; CHECK-O-NEXT: Running analysis: DominatorTreeAnalysis
 ; CHECK-O-NEXT: Running pass: EarlyCSEPass
 ; CHECK-O-NEXT: Running analysis: TargetLibraryAnalysis
 ; CHECK-O3-NEXT: Running pass: CallSiteSplittingPass
 ; CHECK-O-NEXT: Running pass: OpenMPOptPass
 ; CHECK-EP-PIPELINE-EARLY-SIMPLIFICATION-NEXT: Running pass: NoOpModulePass
 ; CHECK-O-NEXT: Running pass: IPSCCPPass
-; CHECK-FUNC-SPEC-NEXT: Running analysis: LoopAnalysis
 ; CHECK-O-NEXT: Running pass: CalledValuePropagationPass
 ; CHECK-O-NEXT: Running pass: GlobalOptPass
 ; CHECK-O-NEXT: Running pass: PromotePass
 ; CHECK-O-NEXT: Running pass: InstCombinePass
 ; CHECK-O-NEXT: Running analysis: OptimizationRemarkEmitterAnalysis
 ; CHECK-O-NEXT: Running analysis: AAManager
 ; CHECK-O-NEXT: Running analysis: BasicAA
 ; CHECK-O-NEXT: Running analysis: ScopedNoAliasAA

 ; CHECK-O1-NEXT: Running pass: LibCallsShrinkWrapPass
 ; CHECK-O2-NEXT: Running pass: LibCallsShrinkWrapPass
 ; CHECK-O3-NEXT: Running pass: LibCallsShrinkWrapPass
 ; CHECK-EP-PEEPHOLE-NEXT: Running pass: NoOpFunctionPass
 ; CHECK-O23SZ-NEXT: Running pass: TailCallElimPass
 ; CHECK-O-NEXT: Running pass: SimplifyCFGPass
 ; CHECK-O-NEXT: Running pass: ReassociatePass
 ; CHECK-O-NEXT: Running pass: LoopSimplifyPass
-; CHECK-NO-FUNC-SPEC-NEXT: Running analysis: LoopAnalysis
+; CHECK-O-NEXT: Running analysis: LoopAnalysis
 ; CHECK-O-NEXT: Running pass: LCSSAPass
 ; CHECK-O-NEXT: Running analysis: ScalarEvolutionAnalysis
 ; CHECK-O-NEXT: Running analysis: InnerAnalysisManagerProxy
 ; CHECK-O-NEXT: Running pass: LoopInstSimplifyPass
 ; CHECK-O-NEXT: Running pass: LoopSimplifyCFGPass
 ; CHECK-O-NEXT: Running pass: LICM
 ; CHECK-O-NEXT: Running pass: LoopRotatePass
 ; CHECK-O-NEXT: Running pass: LICM

llvm/test/Other/new-pm-lto-defaults.ll

 ; Basic test for the new LTO pipeline.
 
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes='lto<O1>' -S %s 2>&1 \
 ; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O1
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes='lto<O1>' -S %s -passes-ep-full-link-time-optimization-early=no-op-module \
 ; RUN:     -passes-ep-full-link-time-optimization-last=no-op-module 2>&1 \
 ; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O1,CHECK-EP
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes='lto<O2>' -S  %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O2,CHECK-O23,CHECK-O23SZ
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O2,CHECK-O23SZ
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes='lto<O2>' -S %s -passes-ep-full-link-time-optimization-early=no-op-module \
 ; RUN:     -passes-ep-full-link-time-optimization-last=no-op-module 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O2,CHECK-O23,CHECK-O23SZ,CHECK-EP
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O2,CHECK-O23SZ,CHECK-EP
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes='lto<O3>' -S  %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O3,CHECK-O23,CHECK-O23SZ
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O3,CHECK-O23SZ
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes='lto<Os>' -S %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-OS,CHECK-OSZ,CHECK-O23SZ
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-OS,CHECK-O23SZ
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes='lto<Oz>' -S %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-OSZ,CHECK-O23SZ
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O23SZ
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes='lto<O3>' -S  %s -passes-ep-peephole='no-op-function' 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O3,CHECK-O23,CHECK-O23SZ,CHECK-EP-Peephole
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O3,CHECK-O23SZ,CHECK-EP-Peephole
 
 ; CHECK-EP: Running pass: NoOpModulePass
 ; CHECK-O: Running pass: CrossDSOCFIPass
 ; CHECK-O-NEXT: Running pass: OpenMPOptPass
 ; CHECK-O-NEXT: Running pass: GlobalDCEPass
 ; CHECK-O-NEXT: Running pass: InferFunctionAttrsPass
 ; CHECK-O-NEXT: Running analysis: InnerAnalysisManagerProxy<{{.*}}Module
 ; CHECK-O-NEXT: Running analysis: TargetLibraryAnalysis
 ; CHECK-O23SZ-NEXT: Running pass: CallSiteSplittingPass on foo
 ; CHECK-O23SZ-NEXT: Running analysis: TargetLibraryAnalysis on foo
 ; CHECK-O23SZ-NEXT: Running analysis: TargetIRAnalysis on foo
 ; CHECK-O23SZ-NEXT: Running analysis: DominatorTreeAnalysis on foo
 ; CHECK-O23SZ-NEXT: PGOIndirectCallPromotion
 ; CHECK-O23SZ-NEXT: Running analysis: ProfileSummaryAnalysis
 ; CHECK-O23SZ-NEXT: Running analysis: OptimizationRemarkEmitterAnalysis
 ; CHECK-O23SZ-NEXT: Running pass: IPSCCPPass
 ; CHECK-O23SZ-NEXT: Running analysis: AssumptionAnalysis on foo
-; CHECK-O23-NEXT: Running analysis: LoopAnalysis on foo
 ; CHECK-O23SZ-NEXT: Running pass: CalledValuePropagationPass
 ; CHECK-O-NEXT: Running analysis: InnerAnalysisManagerProxy<{{.*}}SCC
 ; CHECK-O-NEXT: Running analysis: LazyCallGraphAnalysis
 ; CHECK-O1-NEXT: Running analysis: TargetLibraryAnalysis
 ; CHECK-O-NEXT: Running analysis: FunctionAnalysisManagerCGSCCProxy
 ; CHECK-O-NEXT: Running analysis: OuterAnalysisManagerProxy<{{.*}}LazyCallGraph{{.*}}>
 ; CHECK-O-NEXT: Running pass: PostOrderFunctionAttrsPass
 ; CHECK-O-NEXT: Running analysis: AAManager

 ; CHECK-O23SZ-NEXT: Running pass: PostOrderFunctionAttrsPass on (foo)
 ; CHECK-O23SZ-NEXT: Running pass: RequireAnalysisPass<{{.*}}GlobalsAA
 ; CHECK-O23SZ-NEXT: Running analysis: GlobalsAA on [module]
 ; CHECK-O23SZ-NEXT: Running analysis: CallGraphAnalysis on [module]
 ; CHECK-O23SZ-NEXT: Running pass: InvalidateAnalysisPass<{{.*}}AAManager
 ; CHECK-O23SZ-NEXT: Invalidating analysis: AAManager on foo
 ; CHECK-O23SZ-NEXT: Running pass: OpenMPOptCGSCCPass on (foo)
 ; CHECK-O23SZ-NEXT: Running pass: LoopSimplifyPass on foo
-; CHECK-OSZ-NEXT: Running analysis: LoopAnalysis on foo
+; CHECK-O23SZ-NEXT: Running analysis: LoopAnalysis on foo
 ; CHECK-O23SZ-NEXT: Running pass: LCSSAPass on foo
 ; CHECK-O23SZ-NEXT: Running analysis: MemorySSAAnalysis on foo
 ; CHECK-O23SZ-NEXT: Running analysis: AAManager on foo
 ; CHECK-O23SZ-NEXT: Running analysis: ScalarEvolutionAnalysis on foo
 ; CHECK-O23SZ-NEXT: Running analysis: InnerAnalysisManagerProxy
 ; CHECK-O23SZ-NEXT: Running pass: LICMPass on loop
 ; CHECK-O23SZ-NEXT: Running pass: GVNPass on foo
 ; CHECK-O23SZ-NEXT: Running analysis: MemoryDependenceAnalysis on foo

llvm/test/Other/new-pm-thinlto-postlink-defaults.ll

 ; The IR below was crafted so as:
 ; 1) To have a loop, so we create a loop pass manager
 ; 2) To be "immutable" in the sense that no pass in the standard
 ;    pipeline will modify it.
 ; Since no transformations take place, we don't expect any analyses
 ; to be invalidated.
 ; Any invalidation that shows up here is a bug, unless we started modifying
 ; the IR, in which case we need to make it immutable harder.
 ;
 ; Postlink pipelines:
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes='thinlto<O1>' -S %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-FUNC-SPEC,CHECK-O1,CHECK-POSTLINK-O,%llvmcheckext
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O1,CHECK-POSTLINK-O,%llvmcheckext
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes='thinlto<O2>' -S  %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-FUNC-SPEC,CHECK-O2,CHECK-O23SZ,CHECK-POSTLINK-O,%llvmcheckext,CHECK-POSTLINK-O2
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O2,CHECK-O23SZ,CHECK-POSTLINK-O,%llvmcheckext,CHECK-POSTLINK-O2
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager -passes-ep-pipeline-start='no-op-module' \
 ; RUN:     -passes='thinlto<O3>' -S  %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-FUNC-SPEC,CHECK-O3,CHECK-O23SZ,CHECK-POSTLINK-O,%llvmcheckext,CHECK-POSTLINK-O3
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O3,CHECK-O23SZ,CHECK-POSTLINK-O,%llvmcheckext,CHECK-POSTLINK-O3
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager -passes-ep-optimizer-early='no-op-module' \
 ; RUN:     -passes='thinlto<O3>' -S  %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-FUNC-SPEC,CHECK-O3,CHECK-O23SZ,CHECK-POSTLINK-O,%llvmcheckext,CHECK-POSTLINK-O3,CHECK-POST-EP-OPT-EARLY
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O3,CHECK-O23SZ,CHECK-POSTLINK-O,%llvmcheckext,CHECK-POSTLINK-O3,CHECK-POST-EP-OPT-EARLY
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager -passes-ep-optimizer-last='no-op-module' \
 ; RUN:     -passes='thinlto<O3>' -S  %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-FUNC-SPEC,CHECK-O3,CHECK-O23SZ,CHECK-POSTLINK-O,%llvmcheckext,CHECK-POSTLINK-O3,CHECK-POST-EP-OPT-LAST
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O3,CHECK-O23SZ,CHECK-POSTLINK-O,%llvmcheckext,CHECK-POSTLINK-O3,CHECK-POST-EP-OPT-LAST
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes='thinlto<Os>' -S %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-NO-FUNC-SPEC,CHECK-O23SZ,CHECK-POSTLINK-O,%llvmcheckext,CHECK-POSTLINK-Os
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O23SZ,CHECK-POSTLINK-O,%llvmcheckext,CHECK-POSTLINK-Os
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes='thinlto<Oz>' -S %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-NO-FUNC-SPEC,CHECK-O23SZ,CHECK-POSTLINK-O,%llvmcheckext
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O23SZ,CHECK-POSTLINK-O,%llvmcheckext
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager -debug-info-for-profiling \
 ; RUN:     -passes='thinlto<O2>' -S  %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-FUNC-SPEC,CHECK-O2,CHECK-O23SZ,CHECK-POSTLINK-O,%llvmcheckext,CHECK-POSTLINK-O2
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O2,CHECK-O23SZ,CHECK-POSTLINK-O,%llvmcheckext,CHECK-POSTLINK-O2
 
 ; Suppress FileCheck --allow-unused-prefixes=false diagnostics.
 ; CHECK-NOEXT: {{^}}
 
 ; CHECK-EP-PIPELINE-START: Running pass: NoOpModulePass
 ; CHECK-DIS: Running analysis: InnerAnalysisManagerProxy
 ; CHECK-DIS-NEXT: Running pass: AddDiscriminatorsPass
 ; CHECK-POSTLINK-O: Running pass: PGOIndirectCallPromotion

 ; CHECK-O-NEXT: Running pass: SROAPass
 ; CHECK-O-NEXT: Running analysis: DominatorTreeAnalysis
 ; CHECK-O-NEXT: Running pass: EarlyCSEPass
 ; CHECK-O-NEXT: Running analysis: TargetLibraryAnalysis
 ; CHECK-O3-NEXT: Running pass: CallSiteSplittingPass
 ; CHECK-O-NEXT: Running pass: OpenMPOptPass
 ; CHECK-POSTLINK-O-NEXT: Running pass: LowerTypeTestsPass
 ; CHECK-O-NEXT: Running pass: IPSCCPPass
-; CHECK-FUNC-SPEC-NEXT: Running analysis: LoopAnalysis
 ; CHECK-O-NEXT: Running pass: CalledValuePropagationPass
 ; CHECK-O-NEXT: Running pass: GlobalOptPass
 ; CHECK-O-NEXT: Running pass: PromotePass
 ; CHECK-O-NEXT: Running pass: InstCombinePass
 ; CHECK-O-NEXT: Running analysis: AAManager
 ; CHECK-O-NEXT: Running analysis: BasicAA
 ; CHECK-O-NEXT: Running analysis: ScopedNoAliasAA
 ; CHECK-O-NEXT: Running analysis: TypeBasedAA

 ; CHECK-O23SZ-NEXT: Running pass: ConstraintEliminationPass
 ; CHECK-O1-NEXT: Running pass: LibCallsShrinkWrapPass
 ; CHECK-O2-NEXT: Running pass: LibCallsShrinkWrapPass
 ; CHECK-O3-NEXT: Running pass: LibCallsShrinkWrapPass
 ; CHECK-O23SZ-NEXT: Running pass: TailCallElimPass
 ; CHECK-O-NEXT: Running pass: SimplifyCFGPass
 ; CHECK-O-NEXT: Running pass: ReassociatePass
 ; CHECK-O-NEXT: Running pass: LoopSimplifyPass
-; CHECK-NO-FUNC-SPEC-NEXT: Running analysis: LoopAnalysis
+; CHECK-O-NEXT: Running analysis: LoopAnalysis
 ; CHECK-O-NEXT: Running pass: LCSSAPass
 ; CHECK-O-NEXT: Running analysis: ScalarEvolutionAnalysis
 ; CHECK-O-NEXT: Running analysis: InnerAnalysisManagerProxy
 ; CHECK-O-NEXT: Running pass: LoopInstSimplifyPass
 ; CHECK-O-NEXT: Running pass: LoopSimplifyCFGPass
 ; CHECK-O-NEXT: Running pass: LICM
 ; CHECK-O-NEXT: Running pass: LoopRotatePass
 ; CHECK-O-NEXT: Running pass: LICM

llvm/test/Other/new-pm-thinlto-postlink-pgo-defaults.ll

 ; Validate ThinLTO post link pipeline when we have instrumentation PGO
 ;
 ; Postlink pipelines:
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes='thinlto<O1>' -S %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O123,CHECK-O1,%llvmcheckext
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O1,%llvmcheckext
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes='thinlto<O2>' -S  %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O123,CHECK-O2,CHECK-O23SZ,%llvmcheckext
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O2,CHECK-O23SZ,%llvmcheckext
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager -passes-ep-pipeline-start='no-op-module' \
 ; RUN:     -passes='thinlto<O3>' -S  %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O123,CHECK-O3,CHECK-O23SZ,%llvmcheckext
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O3,CHECK-O23SZ,%llvmcheckext
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes='thinlto<Os>' -S %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-OSZ,CHECK-Os,CHECK-O23SZ,%llvmcheckext
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-Os,CHECK-O23SZ,%llvmcheckext
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -passes='thinlto<Oz>' -S %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-OSZ,CHECK-O23SZ,%llvmcheckext
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O23SZ,%llvmcheckext
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager -debug-info-for-profiling \
 ; RUN:     -passes='thinlto<O2>' -S  %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O123,CHECK-O2,CHECK-O23SZ,%llvmcheckext
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O2,CHECK-O23SZ,%llvmcheckext
 
 ; Suppress FileCheck --allow-unused-prefixes=false diagnostics.
 ; CHECK-NOEXT: {{^}}
 
 ; CHECK-EP-PIPELINE-START: Running pass: NoOpModulePass
 ; CHECK-O: Running pass: PGOIndirectCallPromotion
 ; CHECK-O-NEXT: Running analysis: ProfileSummaryAnalysis
 ; CHECK-O-NEXT: Running analysis: InnerAnalysisManagerProxy
 ; CHECK-O-NEXT: Running analysis: OptimizationRemarkEmitterAnalysis
 ; CHECK-O-NEXT: Running pass: InferFunctionAttrsPass
 ; CHECK-O-NEXT: Running analysis: TargetLibraryAnalysis
 ; CHECK-O-NEXT: Running pass: CoroEarlyPass
 ; CHECK-O-NEXT: Running pass: LowerExpectIntrinsicPass
 ; CHECK-O-NEXT: Running pass: SimplifyCFGPass
 ; CHECK-O-NEXT: Running analysis: TargetIRAnalysis
 ; CHECK-O-NEXT: Running analysis: AssumptionAnalysis
 ; CHECK-O-NEXT: Running pass: SROAPass
 ; CHECK-O-NEXT: Running analysis: DominatorTreeAnalysis
 ; CHECK-O-NEXT: Running pass: EarlyCSEPass
 ; CHECK-O-NEXT: Running analysis: TargetLibraryAnalysis
 ; CHECK-O3-NEXT: Running pass: CallSiteSplittingPass
 ; CHECK-O-NEXT: Running pass: OpenMPOptPass
 ; CHECK-O-NEXT: Running pass: LowerTypeTestsPass
 ; CHECK-O-NEXT: Running pass: IPSCCPPass
-; CHECK-O123-NEXT: Running analysis: LoopAnalysis on foo
 ; CHECK-O-NEXT: Running pass: CalledValuePropagationPass
 ; CHECK-O-NEXT: Running pass: GlobalOptPass
 ; CHECK-O-NEXT: Running pass: PromotePass
 ; CHECK-O-NEXT: Running pass: InstCombinePass
 ; CHECK-O-NEXT: Running analysis: AAManager
 ; CHECK-O-NEXT: Running analysis: BasicAA
 ; CHECK-O-NEXT: Running analysis: ScopedNoAliasAA
 ; CHECK-O-NEXT: Running analysis: TypeBasedAA
 ; CHECK-O-NEXT: Running analysis: OuterAnalysisManagerProxy
 ; CHECK-O-NEXT: Running analysis: BlockFrequencyAnalysis on foo
 ; CHECK-O-NEXT: Running analysis: BranchProbabilityAnalysis on foo
-; CHECK-OSZ-NEXT: Running analysis: LoopAnalysis on foo
+; CHECK-O-NEXT: Running analysis: LoopAnalysis on foo
 ; CHECK-O-NEXT: Running analysis: PostDominatorTreeAnalysis on foo
 ; CHECK-O-NEXT: Running pass: SimplifyCFGPass
 ; CHECK-O-NEXT: Running pass: ModuleInlinerWrapperPass
 ; CHECK-O-NEXT: Running analysis: InlineAdvisorAnalysis
 ; CHECK-O-NEXT: Running pass: RequireAnalysisPass<{{.*}}GlobalsAA
 ; CHECK-O-NEXT: Running analysis: GlobalsAA
 ; CHECK-O-NEXT: Running analysis: CallGraphAnalysis
 ; CHECK-O-NEXT: Running pass: InvalidateAnalysisPass<{{.*}}AAManager

llvm/test/Other/new-pm-thinlto-postlink-samplepgo-defaults.ll

 ; Validate ThinLTO postlink pipeline when we have Sample PGO
 ;
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -pgo-kind=pgo-sample-use-pipeline -profile-file='%S/Inputs/new-pm-thinlto-samplepgo-defaults.prof' \
 ; RUN:     -passes='thinlto<O1>' -S %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O123,CHECK-O1,%llvmcheckext
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O1,%llvmcheckext
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -pgo-kind=pgo-sample-use-pipeline -profile-file='%S/Inputs/new-pm-thinlto-samplepgo-defaults.prof' \
 ; RUN:     -passes='thinlto<O2>' -S  %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O123,CHECK-O2,CHECK-O23SZ,%llvmcheckext
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O2,CHECK-O23SZ,%llvmcheckext
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager -passes-ep-pipeline-start='no-op-module' \
 ; RUN:     -pgo-kind=pgo-sample-use-pipeline -profile-file='%S/Inputs/new-pm-thinlto-samplepgo-defaults.prof' \
 ; RUN:     -passes='thinlto<O3>' -S  %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O123,CHECK-O3,CHECK-O23SZ,%llvmcheckext
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O3,CHECK-O23SZ,%llvmcheckext
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -pgo-kind=pgo-sample-use-pipeline -profile-file='%S/Inputs/new-pm-thinlto-samplepgo-defaults.prof' \
 ; RUN:     -passes='thinlto<Os>' -S %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-OSZ,CHECK-Os,CHECK-O23SZ,%llvmcheckext
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-Os,CHECK-O23SZ,%llvmcheckext
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager \
 ; RUN:     -pgo-kind=pgo-sample-use-pipeline -profile-file='%S/Inputs/new-pm-thinlto-samplepgo-defaults.prof' \
 ; RUN:     -passes='thinlto<Oz>' -S %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-OSZ,CHECK-O23SZ,%llvmcheckext
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O23SZ,%llvmcheckext
 ; RUN: opt -disable-verify -verify-analysis-invalidation=0 -eagerly-invalidate-analyses=0 -debug-pass-manager -debug-info-for-profiling \
 ; RUN:     -pgo-kind=pgo-sample-use-pipeline -profile-file='%S/Inputs/new-pm-thinlto-samplepgo-defaults.prof' \
 ; RUN:     -passes='thinlto<O2>' -S  %s 2>&1 \
-; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O123,CHECK-O2,CHECK-O23SZ,%llvmcheckext
+; RUN:     | FileCheck %s --check-prefixes=CHECK-O,CHECK-O2,CHECK-O23SZ,%llvmcheckext
 
 ; Suppress FileCheck --allow-unused-prefixes=false diagnostics.
 ; CHECK-NOEXT: {{^}}
 
 ; CHECK-EP-PIPELINE-START: Running pass: NoOpModulePass
 ; CHECK-O: Running pass: InferFunctionAttrsPass
 ; CHECK-O-NEXT: Running analysis: InnerAnalysisManagerProxy
 ; CHECK-O-NEXT: Running analysis: TargetLibraryAnalysis

 ; CHECK-O-NEXT: Running analysis: ProfileSummaryAnalysis
 ; CHECK-O-NEXT: Running analysis: LazyCallGraphAnalysis
 ; CHECK-O-NEXT: Running pass: RequireAnalysisPass<{{.*}}ProfileSummaryAnalysis
 ; CHECK-O-NEXT: Running pass: PGOIndirectCallPromotion
 ; CHECK-O-NEXT: Running analysis: OptimizationRemarkEmitterAnalysis
 ; CHECK-O-NEXT: Running pass: OpenMPOptPass
 ; CHECK-O-NEXT: Running pass: LowerTypeTestsPass
 ; CHECK-O-NEXT: Running pass: IPSCCPPass
-; CHECK-O123-NEXT: Running analysis: LoopAnalysis on foo
 ; CHECK-O-NEXT: Running pass: CalledValuePropagationPass
 ; CHECK-O-NEXT: Running pass: GlobalOptPass
 ; CHECK-O-NEXT: Running pass: PromotePass
 ; CHECK-O-NEXT: Running pass: InstCombinePass
 ; CHECK-O-NEXT: Running analysis: AAManager on foo
 ; CHECK-O-NEXT: Running analysis: BasicAA
 ; CHECK-O-NEXT: Running analysis: ScopedNoAliasAA
 ; CHECK-O-NEXT: Running analysis: TypeBasedAA
 ; CHECK-O-NEXT: Running analysis: OuterAnalysisManagerProxy
 ; CHECK-O-NEXT: Running analysis: BlockFrequencyAnalysis on foo
 ; CHECK-O-NEXT: Running analysis: BranchProbabilityAnalysis on foo
-; CHECK-OSZ-NEXT: Running analysis: LoopAnalysis on foo
+; CHECK-O-NEXT: Running analysis: LoopAnalysis on foo
 ; CHECK-O-NEXT: Running analysis: PostDominatorTreeAnalysis on foo
 ; CHECK-O-NEXT: Running pass: SimplifyCFGPass on foo
 ; CHECK-O-NEXT: Running pass: ModuleInlinerWrapperPass
 ; CHECK-O-NEXT: Running analysis: InlineAdvisorAnalysis
 ; CHECK-O-NEXT: Running pass: RequireAnalysisPass<{{.*}}GlobalsAA
 ; CHECK-O-NEXT: Running analysis: GlobalsAA
 ; CHECK-O-NEXT: Running analysis: CallGraphAnalysis
 ; CHECK-O-NEXT: Running pass: InvalidateAnalysisPass<{{.*}}AAManager

llvm/test/Transforms/FunctionSpecialization/function-specialization-always-inline.ll

-; RUN: opt -passes="ipsccp<func-spec>" -funcspec-avg-loop-iters=3 -funcspec-min-function-size=10 -S < %s | FileCheck %s
+; RUN: opt -passes="ipsccp<func-spec>" -force-specialization -S < %s | FileCheck %s
 
 ; CHECK-NOT: foo.{{[0-9]+}}
 
 target datalayout = "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128"
 
 @A = external dso_local constant i32, align 4
 @B = external dso_local constant i32, align 4
 @C = external dso_local constant i32, align 4

llvm/test/Transforms/FunctionSpecialization/function-specialization-constant-integers.ll

-; RUN: opt -passes="ipsccp<func-spec>" -funcspec-for-literal-constant=true -funcspec-min-function-size=10 -S < %s | FileCheck %s
+; RUN: opt -passes="ipsccp<func-spec>" -funcspec-for-literal-constant=true -force-specialization -S < %s | FileCheck %s
 
 ; Check that the literal constant parameter could be specialized.
 ; CHECK: @foo.1(
 ; CHECK: @foo.2(
 
 target datalayout = "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128"
 
 declare i32 @getValue()

llvm/test/Transforms/FunctionSpecialization/function-specialization-loop.ll

-; RUN: opt -passes="ipsccp<func-spec>" -funcspec-avg-loop-iters=5 -funcspec-min-function-size=10 -S < %s | FileCheck %s
-
-; Check that the loop depth results in a larger specialization bonus.
-; CHECK: @foo.1(
-; CHECK: @foo.2(
-
-target datalayout = "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128"
-
-@A = external dso_local constant i32, align 4
-@B = external dso_local constant i32, align 4
-@C = external dso_local constant i32, align 4
-@D = external dso_local constant i32, align 4
-
-declare i1 @cond_begin()
-declare i1 @cond_end()
-declare i1 @getCond()
-
-define internal i32 @foo(i32 %x, ptr %b, ptr %c) {
-entry:
-  br label %loop.entry
-
-loop.entry:
-  br label %loop2.entry
-
-loop2.entry:
-  br label %loop2.body
-
-loop2.body:
-  %0 = load i32, ptr %b, align 4
-  %1 = load i32, ptr %c, align 4
-  %add.0 = add nsw i32 %0, %1
-  %add = add nsw i32 %add.0, %x
-  br label %loop2.end
-
-loop2.end:
-  %cond.end = call i1 @cond_end()
-  br i1 %cond.end, label %loop2.entry, label %loop.end
-
-loop.end:
-  %cond2.end = call i1 @getCond()
-  br i1 %cond2.end, label %loop.entry, label %return
-
-return:
-  ret i32 %add
-}
-
-define dso_local i32 @bar(i32 %x, i32 %y) {
-entry:
-  %tobool = icmp ne i32 %x, 0
-  br i1 %tobool, label %if.then, label %if.else
-
-if.then:
-  %call = call i32 @foo(i32 %x, ptr @A, ptr @C)
-  br label %return
-
-if.else:
-  %call1 = call i32 @foo(i32 %y, ptr @B, ptr @D)
-  br label %return
-
-return:
-  %retval.0 = phi i32 [ %call, %if.then ], [ %call1, %if.else ]
-  ret i32 %retval.0
-}

llvm/test/Transforms/FunctionSpecialization/function-specialization2.ll

 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
 ; RUN: opt -passes="ipsccp<func-spec>,deadargelim" -force-specialization -S < %s | FileCheck %s
 ; RUN: opt -passes="ipsccp<func-spec>,deadargelim" -funcspec-max-iters=1 -force-specialization -S < %s | FileCheck %s
 ; RUN: opt -passes="ipsccp<func-spec>,deadargelim" -funcspec-max-iters=0 -force-specialization -S < %s | FileCheck %s --check-prefix=DISABLED
-; RUN: opt -passes="ipsccp<func-spec>,deadargelim" -funcspec-avg-loop-iters=1 -force-specialization -S < %s | FileCheck %s
 
 ; DISABLED-NOT: @func.1(
 ; DISABLED-NOT: @func.2(
 
 define internal i32 @func(ptr %0, i32 %1, ptr nocapture %2) {
   %4 = alloca i32, align 4
   store i32 %1, ptr %4, align 4
   %5 = load i32, ptr %4, align 4

llvm/test/Transforms/FunctionSpecialization/function-specialization3.ll

-; RUN: opt -passes="ipsccp<func-spec>" -funcspec-avg-loop-iters=3 -S < %s | \
+; RUN: opt -passes="ipsccp<func-spec>" -S < %s | \
 ; RUN:   FileCheck %s --check-prefixes=COMMON,DISABLED
 ; RUN: opt -passes="ipsccp<func-spec>" -force-specialization -S < %s | \
 ; RUN:   FileCheck %s --check-prefixes=COMMON,FORCE
-; RUN: opt -passes="ipsccp<func-spec>" -funcspec-avg-loop-iters=3 -force-specialization -S < %s | \
-; RUN:   FileCheck %s --check-prefixes=COMMON,FORCE
 
 ; Test for specializing a constant global.
 
 target datalayout = "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128"
 
 @A = external dso_local constant i32, align 4
 @B = external dso_local constant i32, align 4