[PGO] Include the mem ops into the function hash.

[hjyamauchi]

Summary

To avoid hash collisions when the only difference is in mem ops.

[MaskRay]

llvm/lib/Transforms/Instrumentation/PGOInstrumentation.cpp

648

2 bits for ValueSites[IPVK_MemOPSize].size(). Is that sufficient?
This deserves a comment.

[davidxl]

Rong has pointed out that having 2 bits may not be enough -- also instead of using | operator, add is better.

Example: for a comdat function with two copies: one has 4 memop sites, while the other has zero. Assuming both has one icall site and cfg and selects are the same, then their resulting hash will still clash if Or operator is used.

Another example, similar to the above, but one has 5 sites, the other has 1 sites -- the resulting hash is also the same. Even though both copies will have vp data statically allocated, we may end up with out of bound access if the inline instance that assumes 5 sites is using the profv with only 1 site statically allocated.

I think we should at least change the '|' to +.

Better yet, just use JamRC to compute the higher 32bit hash using the four values.

llvm/lib/Transforms/Instrumentation/PGOInstrumentation.cpp

646–647

The comment looks stale.

[hjyamauchi]

Use JamCRC.

[hjyamauchi]

llvm/lib/Transforms/Instrumentation/PGOInstrumentation.cpp

646–647

I think the 4 bits are still reserved for CSPGO. See https://reviews.llvm.org/rG6cdf3d8086fe.

[MaskRay]

llvm/lib/Transforms/Instrumentation/PGOInstrumentation.cpp

627–628

To make sure I understand: we use two CRCs instead of one CRC because we want to extract low/high 32 bits for debugging purposes?

Otherwise, we can just use one CRC.

[hjyamauchi]

llvm/lib/Transforms/Instrumentation/PGOInstrumentation.cpp

627–628

JamCRC's result is 32-bit, but we have 64-bit (actually 60-bits) of spare room. Using more bits should decrease the chance of hash collisions.

[hjyamauchi]

llvm/lib/Transforms/Instrumentation/PGOInstrumentation.cpp

647–671

Actually I think it'd be better to shift by 28 here rather than throwing out the top 4 bits for reservation. Also, adding would be better than or'ing. Will update.

[davidxl]

We may also need to bump both the raw and index format version with this change. For the profile use side, we also need to keep the hashing scheme of the older version (in profile-use side). More details to come.

Many tests can also be enhanced to filter out the hash details if they are not part the main test.

llvm/lib/Transforms/Instrumentation/PGOInstrumentation.cpp

627–628

JamCRC produces a 32bit value.

[davidxl]

On version bump --- looks like FrontPGO has been bumping version for hashing changes while IR PGO had not, so it is ok to leave the version unchanged (current situation is also confusing as the version of IR and FE PGO are mixed).

On the other hand, just in case, we need to introduce a temporary internal option for people to be able to keep on using old profile (with older scheme of hashing) for a while. Basically, under the option, the hashing scheme falls back to the old way.

other than that, looks fine.

[hjyamauchi]

Shift the higher 32 bits by 28 bits and add.

[hjyamauchi]

Many tests can also be enhanced to filter out the hash details if they are not part the main test.

Done.

[hjyamauchi]

Add a flag to back out to the old hashing.

[hjyamauchi]

In D84782#2180432, @davidxl wrote:

On version bump --- looks like FrontPGO has been bumping version for hashing changes while IR PGO had not, so it is ok to leave the version unchanged (current situation is also confusing as the version of IR and FE PGO are mixed).

On the other hand, just in case, we need to introduce a temporary internal option for people to be able to keep on using old profile (with older scheme of hashing) for a while. Basically, under the option, the hashing scheme falls back to the old way.

other than that, looks fine.

Thanks. Done.

[davidxl]

Can you split out the test changes and commit it separately?

[hjyamauchi]

Rebase (converting one more test) and fixing a typo and whitespace.

[hjyamauchi]

In D84782#2180578, @davidxl wrote:

Can you split out the test changes and commit it separately?

How exactly? Do you mean commit the non-test part without flipping the flag and then flip it with the test changes?

[davidxl]

changes like in llvm/test/Transforms/PGOProfile/PR41279.ll etc can be independently committed.

[MaskRay]

llvm/lib/Transforms/Instrumentation/PGOInstrumentation.cpp

266

Nit: descriptions usually don't end with a period

(I know that some descriptions in this file are not consistent)

[hjyamauchi]

Address comment.

llvm/lib/Transforms/Instrumentation/PGOInstrumentation.cpp

266

Done.

[hjyamauchi]

In D84782#2180626, @davidxl wrote:

changes like in llvm/test/Transforms/PGOProfile/PR41279.ll etc can be independently committed.

Uploaded D84865 for this.

[hjyamauchi]

Rebase past D84865.

[davidxl]

llvm/test/Transforms/PGOProfile/Inputs/multiple_hash_profile.proftext

1

We can convert this test case to cover the new option introduced:

basically create another profile entry for _Z3fooi with the old hash. Change the counter value a little and expect the profile-use match the old entry when the option is used.

[hjyamauchi]

Address comment.

llvm/test/Transforms/PGOProfile/Inputs/multiple_hash_profile.proftext

1

Done.

[davidxl]

lgtm (with the small test enhancement)

llvm/test/Transforms/PGOProfile/Inputs/multiple_hash_profile.proftext

10

nit: change 12 to a different value say 6.(otherwise if the option is an nop, the test will still succeed).

llvm/test/Transforms/PGOProfile/multiple_hash_profile.ll

3

Use a different prefix like CHECKOLD

33–36

CHECKOLD expects a different weight.

[MaskRay]

LGTM as well with @davidxl's comments addressed.

[hjyamauchi]

Address comments. PTAL.

llvm/test/Transforms/PGOProfile/Inputs/multiple_hash_profile.proftext

10

Done.

llvm/test/Transforms/PGOProfile/multiple_hash_profile.ll

3

Done.

33–36

Done.

[davidxl]

lgtm

Just realized that we need a test case to show it fixes the original issue (existence with memop --> different hash). Ok as a follow up .

[hjyamauchi]

Builtbot failure: http://lab.llvm.org:8011/builders/clang-ppc64be-linux/builds/51984

I think it's an endian issue in the hash computation.

Will revert.

[davidxl]

right. It occurred to me during review, but did not think of the hard coded
values in proftext depends on LE.

[MaskRay]

llvm/lib/Transforms/Instrumentation/PGOInstrumentation.cpp

661

#include "llvm/Support/Endian.h"

and use support::endian::write64le(&Data.N, (uint64_t)SIVisitor.getNumOfSelectInsts())

[MaskRay]

llvm/lib/Transforms/Instrumentation/PGOInstrumentation.cpp

661

Sorry, just use a plain uint8_t C[8]; and support::endian::write64le(C, (uint64_t)SIVisitor.getNumOfSelectInsts())

[hjyamauchi]

Fix the endianness issue.

[hjyamauchi]

llvm/lib/Transforms/Instrumentation/PGOInstrumentation.cpp

661

I went for the same style (using a vector) as the above code (line 642).

[hjyamauchi]

Here's the diff in the latest update:

< +    union {
< +      uint64_t N;
< +      uint8_t C[8];
< +    } Data;
< +    Data.N = (uint64_t)SIVisitor.getNumOfSelectInsts();
< +    JCH.update(Data.C);
< +    Data.N = (uint64_t)ValueSites[IPVK_IndirectCallTarget].size();
< +    JCH.update(Data.C);
< +    Data.N = (uint64_t)ValueSites[IPVK_MemOPSize].size();
< +    JCH.update(Data.C);
< +    Data.N = (uint64_t)MST.AllEdges.size();
< +    JCH.update(Data.C);
---
> +    auto updateJCH = [&JCH](uint64_t Num) {
> +      std::vector<uint8_t> Data;
> +      for (unsigned I = 0; I < 8; ++I)
> +        Data.push_back((uint8_t)(Num >> (I * 8)));
> +      JCH.update(Data);
> +    };
> +    updateJCH((uint64_t)SIVisitor.getNumOfSelectInsts());
> +    updateJCH((uint64_t)ValueSites[IPVK_IndirectCallTarget].size());
> +    updateJCH((uint64_t)ValueSites[IPVK_MemOPSize].size());
> +    updateJCH((uint64_t)MST.AllEdges.size());

[hjyamauchi]

Use endian::write64le.

[hjyamauchi]

Latest update diff:

< +      std::vector<uint8_t> Data;
< +      for (unsigned I = 0; I < 8; ++I)
< +        Data.push_back((uint8_t)(Num >> (I * 8)));
---
> +      uint8_t Data[8];
> +      support::endian::write64le(Data, Num);

llvm/lib/Transforms/Instrumentation/PGOInstrumentation.cpp

661

Now uses write64le.

[davidxl]

lgtm

[MaskRay]

Relanded as 3d6f53018f845e893ad34f64ff2851a2e5c3ba1d

@yamauchi For a reland, you still need to include Differential Revision: so that the differential can be closed automatically when you push the commit.

[MaskRay]

It is also a convention to explain what has changed compared with the initial land.

As a hindsight, the option -pgo-instr-old-cfg-hashing should probably have been mentioned in the description.

[hjyamauchi]

Yup, -pgo-instr-old-cfg-hashing=true to revert back to the old hashing.

[MaskRay]

@yamauchi Do we need cd890944ad344b1b8cac58332ab11c9eec6b61e9 and 3d6f53018f845e893ad34f64ff2851a2e5c3ba1d in https://github.com/llvm/llvm-project/tree/release/11.x ?

+@hans

[hjyamauchi]

In D84782#2191243, @MaskRay wrote:

@yamauchi Do we need cd890944ad344b1b8cac58332ab11c9eec6b61e9 and 3d6f53018f845e893ad34f64ff2851a2e5c3ba1d in https://github.com/llvm/llvm-project/tree/release/11.x ?

I think it'd be good to have them, if possible, though it's a latent, non-recent bug.

[hans]

In D84782#2191429, @yamauchi wrote:

In D84782#2191243, @MaskRay wrote:

@yamauchi Do we need cd890944ad344b1b8cac58332ab11c9eec6b61e9 and 3d6f53018f845e893ad34f64ff2851a2e5c3ba1d in https://github.com/llvm/llvm-project/tree/release/11.x ?

I think it'd be good to have them, if possible, though it's a latent, non-recent bug.

They're hard to apply without 50da55a58534e9207d8d5e31c8b4b5cf0c624175. Do you think we should take that also? Or maybe this can wait since it's not a new bug.

[llvm-commits]

• msg-20731-208.txt163 BDownload

clang/test/CodeGen/Inputs/thinlto_expect1.proftext

 # IR level Instrumentation Flag
 :ir
 foo
 # Func Hash:
-25571299074
+784007059655560962
 # Num Counters:
 2
 # Counter Values:
 12
 24
 

clang/test/CodeGen/Inputs/thinlto_expect2.proftext

 # CSIR level Instrumentation Flag
 :csir
 foo
 # Func Hash:
-25571299074
+784007059655560962
 # Num Counters:
 2
 # Counter Values:
 12
 24
 
 foo
 # Func Hash:
-1152921530178146050
+1936928564262407938
 # Num Counters:
 2
 # Counter Values:
 24
 12
 

clang/test/CodeGenCXX/Inputs/profile-remap.proftext

 :ir
 _ZN3Foo8functionENS_1XE
-29667547796
+146835647075900052
 2
 10
 90
 

clang/test/CodeGenCXX/Inputs/profile-remap_entry.proftext

 :ir
 :entry_first
 _ZN3Foo8functionENS_1XE
-29667547796
+146835647075900052
 2
 100
 90
 

clang/test/Profile/Inputs/gcc-flag-compatibility_IR.proftext

 # IR level Instrumentation Flag
 :ir
 main
 # Func Hash:
-34137660316
+1063705162469825436
 # Num Counters:
 2
 # Counter Values:
 100
 1
 

clang/test/Profile/Inputs/gcc-flag-compatibility_IR_entry.proftext

 # IR level Instrumentation Flag
 :ir
 :entry_first
 main
 # Func Hash:
-34137660316
+1063705162469825436
 # Num Counters:
 2
 # Counter Values:
 1
 100
 

compiler-rt/test/profile/Linux/instrprof-value-merge.c

for (i = 0; i < 6; i++)
       memcpy((void *)(dst + 2), (void *)src, n + 1);
     for (i = 0; i < 66; i++)
       memcpy((void *)(dst + 9), (void *)src, n + 2);
   }
 }
 
 // CHECK: Counters:
 // CHECK:   main:
-// CHECK:     Hash: 0x00030012a7ab6e87
+// CHECK:     Hash: 0x0a9bd81e87ab6e87
 // CHECK:     Counters: 6
 // CHECK:     Indirect Call Site Count: 3
 // CHECK:     Number of Memory Intrinsics Calls: 3
 // CHECK:     Block counts: [27, 297, 12, 132, 3, 2]
 // CHECK:     Indirect Target Results:
 // CHECK:         [ 0, foo, 3 ]
 // CHECK:         [ 1, foo, 27 ]
 // CHECK:         [ 2, foo, 297 ]

llvm/lib/Transforms/Instrumentation/PGOInstrumentation.cpp

 // Command line option to turn on CFG dot dump after profile annotation.
 // Defined in Analysis/BlockFrequencyInfo.cpp:  -pgo-view-counts
 extern cl::opt<PGOViewCountsType> PGOViewCounts;
 
 // Command line option to specify the name of the function for CFG dump
 // Defined in Analysis/BlockFrequencyInfo.cpp:  -view-bfi-func-name=
 extern cl::opt<std::string> ViewBlockFreqFuncName;
 
+static cl::opt<bool>
+    PGOOldCFGHashing("pgo-instr-old-cfg-hashing", cl::init(false), cl::Hidden,
+                     cl::desc("Use the old CFG function hashing"));
+
 // Return a string describing the branch condition that can be
 // used in static branch probability heuristics:
 static std::string getBranchCondString(Instruction *TI) {
   BranchInst *BI = dyn_cast<BranchInst>(TI);
   if (!BI || !BI->isConditional())
     return std::string();
 
   Value *Cond = BI->getCondition();
FuncPGOInstrumentation(
     if (CreateGlobalVar)
       FuncNameVar = createPGOFuncNameVar(F, FuncName);
   }
 };
 
 } // end anonymous namespace
 
 // Compute Hash value for the CFG: the lower 32 bits are CRC32 of the index
-// value of each BB in the CFG. The higher 32 bits record the number of edges.
+// value of each BB in the CFG. The higher 32 bits are the CRC32 of the numbers
+// of selects, indirect calls, mem ops and edges.
 template <class Edge, class BBInfo>
 void FuncPGOInstrumentation<Edge, BBInfo>::computeCFGHash() {
   std::vector<uint8_t> Indexes;
   JamCRC JC;
   for (auto &BB : F) {
     const Instruction *TI = BB.getTerminator();
     for (unsigned I = 0, E = TI->getNumSuccessors(); I != E; ++I) {
       BasicBlock *Succ = TI->getSuccessor(I);
       auto BI = findBBInfo(Succ);
       if (BI == nullptr)
         continue;
       uint32_t Index = BI->Index;
       for (int J = 0; J < 4; J++)
         Indexes.push_back((uint8_t)(Index >> (J * 8)));
     }
   }
   JC.update(Indexes);
 
+  JamCRC JCH;
+  if (PGOOldCFGHashing) {
     // Hash format for context sensitive profile. Reserve 4 bits for other
     // information.
     FunctionHash = (uint64_t)SIVisitor.getNumOfSelectInsts() << 56 |
                    (uint64_t)ValueSites[IPVK_IndirectCallTarget].size() << 48 |
                    //(uint64_t)ValueSites[IPVK_MemOPSize].size() << 40 |
                    (uint64_t)MST.AllEdges.size() << 32 | JC.getCRC();
+  } else {
+    // The higher 32 bits.
+    auto updateJCH = [&JCH](uint64_t Num) {
+      uint8_t Data[8];
+      support::endian::write64le(Data, Num);
+      JCH.update(Data);
+    };
+    updateJCH((uint64_t)SIVisitor.getNumOfSelectInsts());
+    updateJCH((uint64_t)ValueSites[IPVK_IndirectCallTarget].size());
+    updateJCH((uint64_t)ValueSites[IPVK_MemOPSize].size());
+    updateJCH((uint64_t)MST.AllEdges.size());
+
+    // Hash format for context sensitive profile. Reserve 4 bits for other
+    // information.
+    FunctionHash = (((uint64_t)JCH.getCRC()) << 28) + JC.getCRC();
+  }
+
   // Reserve bit 60-63 for other information purpose.
   FunctionHash &= 0x0FFFFFFFFFFFFFFF;
   if (IsCS)
     NamedInstrProfRecord::setCSFlagInHash(FunctionHash);
   LLVM_DEBUG(dbgs() << "Function Hash Computation for " << F.getName() << ":\n"
                     << " CRC = " << JC.getCRC()
                     << ", Selects = " << SIVisitor.getNumOfSelectInsts()
                     << ", Edges = " << MST.AllEdges.size() << ", ICSites = "
-                    << ValueSites[IPVK_IndirectCallTarget].size()
-                    << ", Hash = " << FunctionHash << "\n";);
+                    << ValueSites[IPVK_IndirectCallTarget].size());
+  if (!PGOOldCFGHashing) {
+    LLVM_DEBUG(dbgs() << ", Memops = " << ValueSites[IPVK_MemOPSize].size()
+                      << ", High32 CRC = " << JCH.getCRC());
+  }
+  LLVM_DEBUG(dbgs() << ", Hash = " << FunctionHash << "\n";);
 }
 
 // Check if we can safely rename this Comdat function.
 static bool canRenameComdat(
     Function &F,
     std::unordered_multimap<Comdat *, GlobalValue *> &ComdatMembers) {
   if (!DoComdatRenaming || !canRenameComdatFunc(F, true))
     return false;

llvm/test/Transforms/PGOProfile/Inputs/PR41279.proftext

 :ir
 foo
-60927483247
+1096621588030135663
 4
 3
 2
 3
 2
 

llvm/test/Transforms/PGOProfile/Inputs/PR41279_2.proftext

 :ir
 f
-62077759478
+1096621589180411894
 2
 3
 2
 

llvm/test/Transforms/PGOProfile/Inputs/branch1.proftext

 # :ir is the flag to indicate this is IR level profile.
 :ir
 test_br_1
-25571299074
+784007059655560962
 2
 3
 2
 

llvm/test/Transforms/PGOProfile/Inputs/branch1_large_count.proftext

 # :ir is the flag to indicate this is IR level profile.
 :ir
 test_br_1
-25571299074
+784007059655560962
 2
 12884901888
 8589934592
 

llvm/test/Transforms/PGOProfile/Inputs/branch2.proftext

 # :ir is the flag to indicate this is IR level profile.
 :ir
 test_br_2
-29667547796
+146835647075900052
 2
 1
 1
 

llvm/test/Transforms/PGOProfile/Inputs/branch2_entry.proftext

 # :ir is the flag to indicate this is IR level profile.
 :ir
 :entry_first
 test_br_2
-29667547796
+146835647075900052
 2
 2
 1
 

llvm/test/Transforms/PGOProfile/Inputs/criticaledge.proftext

 # :ir is the flag to indicate this is IR level profile.
 :ir
 test_criticalEdge
-82323253069
+93478046750287693
 8
 2
 1
 2
 2
 0
 1
 2
 1
 
 <stdin>:bar
-12884901887
+742261418966908927
 1
 7
 

llvm/test/Transforms/PGOProfile/Inputs/criticaledge_entry.proftext

 # :ir is the flag to indicate this is IR level profile.
 :ir
 :entry_first
 test_criticalEdge
-82323253069
+93478046750287693
 8
 7
 2
 1
 2
 0
 1
 2
 1
 
 <stdin>:bar
-12884901887
+742261418966908927
 1
 7
 

llvm/test/Transforms/PGOProfile/Inputs/cspgo.proftext

 # Num Counters:
 2
 # Counter Values:
 99938
 62
 
 foo
 # Func Hash:
-1152921640672869708
+1456607294772657484
 # Num Counters:
 10
 # Counter Values:
 100000
 100000
 0
 66666
 66666
 0
 100000
 66667
 100000
 1
 
 foo
 # Func Hash:
-29212902728
+146835646621254984
 # Num Counters:
 2
 # Counter Values:
 100000
 1
 
 bar
 # Func Hash:
-1152921569533132113
+1440408129826749777
 # Num Counters:
 5
 # Counter Values:
 0
 0
 0
 0
 0
 
 bar
 # Func Hash:
-56228292833
+567185239050791137
 # Num Counters:
 4
 # Counter Values:
 800000
 399999
 100000
 100000
 
 main
 # Func Hash:
-1152921517491748863
+1895182923573755903
 # Num Counters:
 1
 # Counter Values:
 1
 
 main
 # Func Hash:
-12884901887
+742261418966908927
 # Num Counters:
 1
 # Counter Values:
 1
 
 csfdo_plain.c:barbar
 # Func Hash:
 1152921517491748863
 # Num Counters:
 1
 # Counter Values:
 100000
 
 csfdo_plain.c:barbar
 # Func Hash:
 12884901887
 # Num Counters:
 1
 # Counter Values:
 100000
 
 goo
 # Func Hash:
-1152921517491748863
+1895182923573755903
 # Num Counters:
 1
 # Counter Values:
 100000
 
 goo
 # Func Hash:
-12884901887
+742261418966908927
 # Num Counters:
 1
 # Counter Values:
 100000
 

llvm/test/Transforms/PGOProfile/Inputs/diag_no_value_sites.proftext

 # :ir is the flag to indicate this is IR level profile.
 :ir
 foo
-12884901887
+48277136972185599
 1
 1

llvm/test/Transforms/PGOProfile/Inputs/fix_entry_count.proftext

 :ir
 :entry_first
 test_simple_for
-34137660316
+1063705162469825436
 2
 0
 96
 

llvm/test/Transforms/PGOProfile/Inputs/func_entry.proftext

 # IR level Instrumentation Flag
 :ir
 :entry_first
 hot
 # Func Hash:
-12884901887
+742261418966908927
 # Num Counters:
 1
 # Counter Values:
 9000
 
 cold
 # Func Hash:
-12884901887
+742261418966908927
 # Num Counters:
 1
 # Counter Values:
 10
 
 med
 # Func Hash:
-12884901887
+742261418966908927
 # Num Counters:
 1
 # Counter Values:
 50

llvm/test/Transforms/PGOProfile/Inputs/indirect_call.proftext

 :ir
 bar
 # Func Hash:
-281487861612543
+170957022131388415
 # Num Counters:
 1
 # Counter Values:
 140
 # Num Value Kinds:
 1
 # ValueKind = IPVK_IndirectCallTarget:
 0
 # NumValueSites:
 1
 3
 func2:80
 func1:40
 func3:20
 
 func1
 # Func Hash:
-12884901887
+742261418966908927
 # Num Counters:
 1
 # Counter Values:
 40
 
 func2
 # Func Hash:
-12884901887
+742261418966908927
 # Num Counters:
 1
 # Counter Values:
 80
 
 func3
 # Func Hash:
-12884901887
+742261418966908927
 # Num Counters:
 1
 # Counter Values:
 20
 

llvm/test/Transforms/PGOProfile/Inputs/indirectbr.proftext

 # IR level Instrumentation Flag
 :ir
 foo
 # Func Hash:
-47485104005
+844982796158316421
 # Num Counters:
 4
 # Counter Values:
 139
 20
 5
 63

llvm/test/Transforms/PGOProfile/Inputs/indirectbr_entry.proftext

 # IR level Instrumentation Flag
 :ir
 :entry_first
 foo
 # Func Hash:
-47485104005
+844982796158316421
 # Num Counters:
 4
 # Counter Values:
 202
 20
 5
 63

llvm/test/Transforms/PGOProfile/Inputs/irreducible.proftext

 :ir
 _Z11irreducibleii
 # Func Hash:
-64451410787
+287486624745028451
 # Num Counters:
 6
 # Counter Values:
 1000
 950
 100
 373
 1
 0
 
 _Z11irreduciblePh
 # Func Hash:
-104649601521
+331779889035882993
 # Num Counters:
 9
 # Counter Values:
 100
 300
 99
 300
 201
 1
 1
 0
 0

llvm/test/Transforms/PGOProfile/Inputs/irreducible_entry.proftext

 :ir
 :entry_first
 _Z11irreducibleii
 # Func Hash:
-64451410787
+287486624745028451
 # Num Counters:
 6
 # Counter Values:
 1
 1000
 950
 100
 373
 0
 
 _Z11irreduciblePh
 # Func Hash:
-104649601521
+331779889035882993
 # Num Counters:
 9
 # Counter Values:
 1
 100
 300
 99
 300
 201
 1
 0
 0

llvm/test/Transforms/PGOProfile/Inputs/landingpad.proftext

 # :ir is the flag to indicate this is IR level profile.
 :ir
 foo
-59130013419
+567185241952511723
 4
 3
 1
 2
 0
 
 bar
-24868915205
+784007058953177093
 2
 3
 2
 

llvm/test/Transforms/PGOProfile/Inputs/landingpad_entry.proftext

 # :ir is the flag to indicate this is IR level profile.
 :ir
 :entry_first
 foo
-59130013419
+567185241952511723
 4
 5
 1
 2
 0
 
 bar
-24868915205
+784007058953177093
 2
 3
 2
 

llvm/test/Transforms/PGOProfile/Inputs/large_count_remarks.proftext

 # :ir is the flag to indicate this is IR level profile.
 :ir
 test
-25571299074
+784007059655560962
 2
 40000000000
 20000000000
 

llvm/test/Transforms/PGOProfile/Inputs/loop1.proftext

 # :ir is the flag to indicate this is IR level profile.
 :ir
 test_simple_for
-34137660316
+1063705162469825436
 2
 96
 4
 

llvm/test/Transforms/PGOProfile/Inputs/loop1_entry.proftext

 # :ir is the flag to indicate this is IR level profile.
 :ir
 :entry_first
 test_simple_for
-34137660316
+1063705162469825436
 2
 4
 96
 

llvm/test/Transforms/PGOProfile/Inputs/loop2.proftext

 # :ir is the flag to indicate this is IR level profile.
 :ir
 test_nested_for
-53929068288
+798733566382720768
 3
 33
 10
 6
 

llvm/test/Transforms/PGOProfile/Inputs/loop2_entry.proftext

 # :ir is the flag to indicate this is IR level profile.
 :ir
 :entry_first
 test_nested_for
-53929068288
+798733566382720768
 3
 6
 33
 10
 

llvm/test/Transforms/PGOProfile/Inputs/memop_size_annotation.proftext

 # IR level Instrumentation Flag
 :ir
 foo
 # Func Hash:
-53929068288
+687116424982578944
 # Num Counters:
 3
 # Counter Values:
 556
 20
 1
 # Num Value Kinds:
 1

llvm/test/Transforms/PGOProfile/Inputs/misexpect-branch-correct.proftext

 # IR level Instrumentation Flag
 :ir
 bar
 # Func Hash:
-29667547796
+146835647075900052
 # Num Counters:
 2
 # Counter Values:
 200000
 0
 
 baz
 # Func Hash:

llvm/test/Transforms/PGOProfile/Inputs/misexpect-branch.proftext

 # IR level Instrumentation Flag
 :ir
 bar
 # Func Hash:
-29667547796
+146835647075900052
 # Num Counters:
 2
 # Counter Values:
 399668
 1600332
 
 baz
 # Func Hash:

llvm/test/Transforms/PGOProfile/Inputs/misexpect-branch_entry.proftext

 # IR level Instrumentation Flag
 :ir
 :entry_first
 bar
 # Func Hash:
-29667547796
+146835647075900052
 # Num Counters:
 2
 # Counter Values:
 2000000
 1600332
 
 baz
 # Func Hash:

llvm/test/Transforms/PGOProfile/Inputs/misexpect-switch-correct.proftext

 # IR level Instrumentation Flag
 :ir
 main
 # Func Hash:
-74054140268
+391331300939170156
 # Num Counters:
 7
 # Counter Values:
 0
 0
 20000
 0
 0
 1
 0
 

llvm/test/Transforms/PGOProfile/Inputs/misexpect-switch-correct_entry.proftext

 # IR level Instrumentation Flag
 :ir
 :entry_first
 main
 # Func Hash:
-74054140268
+391331300939170156
 # Num Counters:
 7
 # Counter Values:
 1
 0
 0
 20000
 0
 0
 0
 

llvm/test/Transforms/PGOProfile/Inputs/misexpect-switch.proftext

 # IR level Instrumentation Flag
 :ir
 main
 # Func Hash:
-74054140268
+391331300939170156
 # Num Counters:
 7
 # Counter Values:
 3973
 3970
 0
 11889
 8111
 1
 0
 

llvm/test/Transforms/PGOProfile/Inputs/misexpect-switch_entry.proftext

 # IR level Instrumentation Flag
 :ir
 :entry_first
 main
 # Func Hash:
-74054140268
+391331300939170156
 # Num Counters:
 7
 # Counter Values:
 11889
 3973
 3970
 0
 8111
 1
 0
 

llvm/test/Transforms/PGOProfile/Inputs/multiple_hash_profile.proftext

 # IR level Instrumentation Flag
 :ir
 _Z3fooi
 # Func Hash:
-72057606922829823
+382993475055910911
 # Num Counters:
 2
 # Counter Values:
 18
 12
 
+# For -pgo-instr-old-cfg-hashing=true
+_Z3fooi
+# Func Hash:
+72057606922829823
+# Num Counters:
+2
+# Counter Values:
+18
+6
+
 _Z3fooi
 # Func Hash:
 12884901887
 # Num Counters:
 1
 # Counter Values:
 0
 
 _Z3bari
 # Func Hash:
+382993475055910911
+# Num Counters:
+2
+# Counter Values:
+0
+0
+
+# For -pgo-instr-old-cfg-hashing=true
+_Z3bari
+# Func Hash:
 72057606922829823
 # Num Counters:
 2
 # Counter Values:
 0
 0
 
 _Z4m2f1v
 # Func Hash:
-12884901887
+742261418966908927
 # Num Counters:
 1
 # Counter Values:
 1
 
+# For -pgo-instr-old-cfg-hashing=true
+_Z4m2f1v
+# Func Hash:
[phone]
+# Num Counters:
+1
+# Counter Values:
+1

llvm/test/Transforms/PGOProfile/Inputs/noreturncall.proftext

 # IR level Instrumentation Flag
 :ir
 foo
 # Func Hash:
-36496524737
+238984482720105921
 # Num Counters:
 3
 # Counter Values:
 21
 21
 0

llvm/test/Transforms/PGOProfile/Inputs/remap.proftext

 # :ir is the flag to indicate this is IR level profile.
 :ir
 _ZN3foo3barERKN1N1XINS_4quuxEEE
-25571299074
+784007059655560962
 2
 3
 2
 

llvm/test/Transforms/PGOProfile/Inputs/select1.proftext

 :ir
 :entry_first
 test_br_2
-72057623705475732
+942389667449461396
 3
 5
 1
 1
 

llvm/test/Transforms/PGOProfile/Inputs/select2.proftext

 # IR level Instrumentation Flag
 :ir
 :entry_first
 foo
 # Func Hash:
-72057628175588252
+134732432632142748
 # Num Counters:
 3
 # Counter Values:
 3
 800
 300

llvm/test/Transforms/PGOProfile/Inputs/suppl-profile.proftext

 # :ir is the flag to indicate this is IR level profile.
 :ir
 test_simple_for
-34137660316
+1063705162469825436
 2
 0
 0
 
 foo
 2582734
 4
 1000
 270
 180
 760

llvm/test/Transforms/PGOProfile/Inputs/switch.proftext

 # :ir is the flag to indicate this is IR level profile.
 :ir
 test_switch
-46200943743
+536873293052540031
 4
 0
 5
 2
 3
 

llvm/test/Transforms/PGOProfile/Inputs/switch_entry.proftext

 # :ir is the flag to indicate this is IR level profile.
 :ir
 :entry_first
 test_switch
-46200943743
+536873293052540031
 4
 10
 5
 2
 3
 

llvm/test/Transforms/PGOProfile/Inputs/thinlto_cs.proftext

 # CSIR level Instrumentation Flag
 :csir
 cond.llvm.11253644763537639171
 # Func Hash:
 1152921517491748863
 # Num Counters:
 1
 # Counter Values:
 200000
 
 foo
 # Func Hash:
-29212902728
+1720106746050921044
 # Num Counters:
 2
 # Counter Values:
 100000
 1
 
 bar
 # Func Hash:
-1152921534274394772
+1299757151682747028
 # Num Counters:
 2
 # Counter Values:
 0
 0
 
 bar
 # Func Hash:

 1152921517491748863
 # Num Counters:
 1
 # Counter Values:
 1
 
 main
 # Func Hash:
-12884901887
+1895182923573755903
 # Num Counters:
 1
 # Counter Values:
 1
 
 cspgo.c:foo
 # Func Hash:
-1152921563228422740
+1720106746050921044
 # Num Counters:
 4
 # Counter Values:
 100000
 100000
 0
 1
 
 cspgo_bar.c:cond
 # Func Hash:
 12884901887
 # Num Counters:
 1
 # Counter Values:
 200000
 

llvm/test/Transforms/PGOProfile/multiple_hash_profile.ll

 ; RUN: llvm-profdata merge %S/Inputs/multiple_hash_profile.proftext -o %t.profdata
 ; RUN: opt < %s -pgo-instr-use -pgo-test-profile-file=%t.profdata  -S | FileCheck %s
+; RUN: opt < %s -pgo-instr-use -pgo-test-profile-file=%t.profdata -pgo-instr-old-cfg-hashing=true -S | FileCheck -check-prefix=CHECKOLDHASH %s
 ; RUN: opt < %s -passes=pgo-instr-use -pgo-test-profile-file=%t.profdata -S | FileCheck %s
+; RUN: opt < %s -passes=pgo-instr-use -pgo-test-profile-file=%t.profdata -pgo-instr-old-cfg-hashing=true -S | FileCheck -check-prefix=CHECKOLDHASH %s
 target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
 target triple = "x86_64-unknown-linux-gnu"
 
 $_Z3fooi = comdat any
 
 @g2 = local_unnamed_addr global i32 (i32)* null, align 8
 
 define i32 @_Z3bari(i32 %i) {

 }
 
 define linkonce_odr i32 @_Z3fooi(i32 %i) comdat {
 entry:
   %cmp.i = icmp sgt i32 %i, 2
   %mul.i = select i1 %cmp.i, i32 1, i32 %i
 ; CHECK: %mul.i = select i1 %cmp.i, i32 1, i32 %i
 ; CHECK-SAME: !prof ![[BW:[0-9]+]]
 ; CHECK: ![[BW]] = !{!"branch_weights", i32 12, i32 6}
+; CHECKOLDHASH: %mul.i = select i1 %cmp.i, i32 1, i32 %i
+; CHECKOLDHASH-SAME: !prof ![[BW:[0-9]+]]
+; CHECKOLDHASH: ![[BW]] = !{!"branch_weights", i32 6, i32 12}
   %retval.0.i = mul nsw i32 %mul.i, %i
   ret i32 %retval.0.i
 }