[llvm-profgen] Support LBR only perf script

[wlei]

Summary

This change aims at supporting LBR only sample perf script which is used for regular(Non-CS) profile generation. A LBR perf script includes a batch of LBR sample which starts with a frame pointer and a group of 32 LBR entries is followed. The FROM/TO LBR pair and the range between two consecutive entries (the former entry's TO and the latter entry's FROM) will be used to infer function profile info.

An example of LBR perf script(created by perf script -F ip,brstack -i perf.data)

40062f 0x40062f/0x4005b0/P/-/-/9  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1 ...
4005d7 0x4005d7/0x4005e5/P/-/-/8  0x40062f/0x4005b0/P/-/-/6  0x400645/0x4005ff/P/-/-/1 ...
...

For implementation:

• Extended a new child class LBRPerfReader for the sample parsing, reused all the functionalities in extractLBRStack except for an extension to parsing leading instruction pointer.
• HybridSample is reused(just leave the call stack empty) and the parsed samples is still aggregated in AggregatedSamples. After that, range samples, branch sample, address samples are computed and recorded.
• Reused ContextSampleCounterMap to store the raw profile, since it's no need to aggregation by context, here it just registered one sample counter with a fake context key.
• Unified to use show-raw-profile instead of show-unwinder-output to dump the intermediate raw profile, see the comments of the format of the raw profile. For CS profile, it remains to output the unwinder output.

Profile generation part will come soon.

[wlei]

add test for mmap event perf script

[hoy]

llvm/tools/llvm-profgen/PerfReader.cpp

657

I'm thinking of separating LBR samples from HybridSample and making HybridSample inherit that. This way they are technically separate and could reduce confusion. What do you think?

llvm/tools/llvm-profgen/PerfReader.h

373

Do we really need this? RangeCounter should cover addresses?

521

Nit: splitting once is enough, instead of unlimited times (-1)?

544

Why need this? Can the count be just skipped since it does not reflect a call stack sample and LBR sample?

[wlei]

llvm/tools/llvm-profgen/PerfReader.cpp

657

Sounds good, changed!

llvm/tools/llvm-profgen/PerfReader.h

373

Good catch. I did check our internal tool, the addressCounter is actually used only without LBR sample, so here we indeed don't need this, thanks!

521

-1(maximum number of times split) is the default value, here is for the 4th parameter which means to not keep the empty string, otherwise there are many empty record, it's not direct to get the first leading pointer. Seems C++ can't skip the middle default value.

544

Here it's in fact to skip it. To distinguish LBR and Hybrid sample, it used Count to indicate call stack exists, >0 means hybrid sample. When adding the aggregated count, it will also increase Count and treat LBR sample as hybrid sample incorrectly.

[wlei]

addressing Hongtao's feedback

[wlei]

fix typo

[wenlei]

Unified to use show-raw-profile instead of show-unwinder-output to dump the intermediate raw profile, see the comments of the format of the raw profile. For CS profile, it remains to output the unwinder output

If these are considered actual profile (as the name show-raw-profile suggests), it's probably better to write to output file instead of dumping to stdout. How about just have a switch skip-symbolization, which writes the raw, unsymbolized profile to output file directly, and then skip all later processing.

The range representation between cs and non-cs profile is slightly different, perhaps they can also be unified.

llvm/tools/llvm-profgen/PerfReader.cpp

657

I actually find the inheritance isn't really necessary now. The hashing specialization in LBRSample does not add value because the general version for HybridSample can handle that too, and a separate hash for LBRSample just adds duplication. On the contrary, how about we rename HybridSample to PerfSample and remove the inheritance structure all together?

Also I don't think HybridSample being subclass of LBRSample is good because this is more about composition. What about if we have a perf sample that only has call stack but not LBR? inheritance wouldn't work well for that (and we don't want virtual inheritance). This is similar to why we don't make subclass for aggregation count.

llvm/tools/llvm-profgen/PerfReader.h

521

Line.split(Records, " ", 1, false); instead?

688

Would an empty string (zero length) work?

llvm/tools/llvm-profgen/llvm-profgen.cpp

95

As an intermediate state, print a warning?

[wlei]

llvm/tools/llvm-profgen/PerfReader.h

521

Sorry, I misunderstood. I tired Line.split(Records, " ", 1, false); but it showed it doesn't work, there are several leading empty space, splitting once will only separate one empty space and the remaining still start with empty space.

[hoy]

llvm/tools/llvm-profgen/PerfReader.cpp

657

Removing the inheritance has a cost of stacking fields that are not necessarily used at the same time together. For example, the SmallVector<uint64_t, 16> CallStack field will be there for LBRSamples and in member functions the unused fields have to be checked. But we don't have virtual method overhead as a result of removing inheritance, which is a cons of OOP.

Multi-inheritance can be use to a separate callstack samples.

I still prefer OOP here from memory and code maintenance and extension point of view. Let me know your thoughts.

llvm/tools/llvm-profgen/PerfReader.h

544

I see. Do we always have an aggregated count for both hybrid and LBR samples? If not, a decimal number can also be a valid call frame addr in which case we may not be able to tell LBR samples apart from hybrid samples.

[wlei]

addressing Wenlei's feedback

[wlei]

If these are considered actual profile (as the name show-raw-profile suggests), it's probably better to write to output file instead of dumping to stdout. How about just have a switch skip-symbolization, which writes the raw, unsymbolized profile to output file directly, and then skip all later processing.

Sounds good to write to the output file, I indeed found the raw profile outputs are mixed with other warning logs which is inconvenient for other tools to use the raw profile. Changed!

The range representation between cs and non-cs profile is slightly different, perhaps they can also be unified.

Can we use a separate patch(will come soon) for the unified format? just for easy review(there should be several tests to be fixed).

llvm/tools/llvm-profgen/PerfReader.h

688

Good, catch! Removed!

llvm/tools/llvm-profgen/llvm-profgen.cpp

95

Sounds good

[wlei]

Remove HybridSample and LBRSample, use one PerfSample instead

[hoy]

lgtm.

[wenlei]

lgtm with minor comments, thanks.

llvm/tools/llvm-profgen/PerfReader.h

521

not a big deal, but this could be faster as it avoids scanning and splitting the entire string:

Line = Line.trim(" ");
Line.split(Records, " ", 1, false);

613–614

nit: now that this is output to a file instead of stdout, rename it as writeRawProfile?

[wlei]

addressing feedbacks.

[wlei]

llvm/tools/llvm-profgen/PerfReader.h

521

Sounds good, I actually found there are two space strings between each LBR entry, so I need to change to split 2 times :)

[wenlei]

llvm/tools/llvm-profgen/PerfReader.h

521

Or Line.split(Records, " ", 1, false);? two space instead of one as the separator. Works either way.

llvm/test/tools/llvm-profgen/Inputs/noprobe.aggperfscript

+1
+           40062f 0x40062f/0x4005b0/P/-/-/9  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/6  0x40062f/0x4005b0/P/-/-/16  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/6  0x40062f/0x4005b0/P/-/-/6  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005c8/0x4005dc/P/-/-/8  0x40062f/0x4005b0/P/-/-/9  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/10  0x40062f/0x4005b0/P/-/-/14  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/7  0x40062f/0x4005b0/P/-/-/8  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005c8/0x4005dc/P/-/-/7  0x40062f/0x4005b0/P/-/-/15  0x400645/0x4005ff/P/-/-/1
+1
+           4005d7 0x4005d7/0x4005e5/P/-/-/8  0x40062f/0x4005b0/P/-/-/6  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/2  0x4005c8/0x4005dc/P/-/-/7  0x40062f/0x4005b0/P/-/-/11  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/8  0x40062f/0x4005b0/P/-/-/9  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/5  0x40062f/0x4005b0/P/-/-/11  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/2  0x4005c8/0x4005dc/P/-/-/7  0x40062f/0x4005b0/P/-/-/10  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/8  0x40062f/0x4005b0/P/-/-/9  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/13  0x40062f/0x4005b0/P/-/-/9
+3
+           4005c8 0x4005c8/0x4005dc/P/-/-/11  0x40062f/0x4005b0/P/-/-/8  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/5  0x40062f/0x4005b0/P/-/-/6  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/12  0x40062f/0x4005b0/P/-/-/6  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/2  0x4005c8/0x4005dc/P/-/-/7  0x40062f/0x4005b0/P/-/-/10  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/8  0x40062f/0x4005b0/P/-/-/9  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/12  0x40062f/0x4005b0/P/-/-/6  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/2  0x4005c8/0x4005dc/P/-/-/8  0x40062f/0x4005b0/P/-/-/8

llvm/test/tools/llvm-profgen/Inputs/noprobe.mmap.perfscript

+PERF_RECORD_MMAP2 121161/121161: [0x400000(0x1000) @ 0 00:23 10094534 144120]: r-xp /home/noprobe.perfbin
+           40062f 0x40062f/0x4005b0/P/-/-/9  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/6  0x40062f/0x4005b0/P/-/-/16  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/6  0x40062f/0x4005b0/P/-/-/6  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005c8/0x4005dc/P/-/-/8  0x40062f/0x4005b0/P/-/-/9  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/10  0x40062f/0x4005b0/P/-/-/14  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/7  0x40062f/0x4005b0/P/-/-/8  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005c8/0x4005dc/P/-/-/7  0x40062f/0x4005b0/P/-/-/15  0x400645/0x4005ff/P/-/-/1
+           4005d7 0x4005d7/0x4005e5/P/-/-/8  0x40062f/0x4005b0/P/-/-/6  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/2  0x4005c8/0x4005dc/P/-/-/7  0x40062f/0x4005b0/P/-/-/11  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/8  0x40062f/0x4005b0/P/-/-/9  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/5  0x40062f/0x4005b0/P/-/-/11  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/2  0x4005c8/0x4005dc/P/-/-/7  0x40062f/0x4005b0/P/-/-/10  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/8  0x40062f/0x4005b0/P/-/-/9  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/13  0x40062f/0x4005b0/P/-/-/9
+           4005c8 0x4005c8/0x4005dc/P/-/-/11  0x40062f/0x4005b0/P/-/-/8  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/5  0x40062f/0x4005b0/P/-/-/6  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/12  0x40062f/0x4005b0/P/-/-/6  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/2  0x4005c8/0x4005dc/P/-/-/7  0x40062f/0x4005b0/P/-/-/10  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/8  0x40062f/0x4005b0/P/-/-/9  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/12  0x40062f/0x4005b0/P/-/-/6  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/2  0x4005c8/0x4005dc/P/-/-/8  0x40062f/0x4005b0/P/-/-/8

llvm/test/tools/llvm-profgen/Inputs/noprobe.perfscript

+           40062f 0x40062f/0x4005b0/P/-/-/9  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/6  0x40062f/0x4005b0/P/-/-/16  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/6  0x40062f/0x4005b0/P/-/-/6  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005c8/0x4005dc/P/-/-/8  0x40062f/0x4005b0/P/-/-/9  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/10  0x40062f/0x4005b0/P/-/-/14  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/7  0x40062f/0x4005b0/P/-/-/8  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005c8/0x4005dc/P/-/-/7  0x40062f/0x4005b0/P/-/-/15  0x400645/0x4005ff/P/-/-/1
+           4005d7 0x4005d7/0x4005e5/P/-/-/8  0x40062f/0x4005b0/P/-/-/6  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/2  0x4005c8/0x4005dc/P/-/-/7  0x40062f/0x4005b0/P/-/-/11  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/8  0x40062f/0x4005b0/P/-/-/9  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/5  0x40062f/0x4005b0/P/-/-/11  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/2  0x4005c8/0x4005dc/P/-/-/7  0x40062f/0x4005b0/P/-/-/10  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/8  0x40062f/0x4005b0/P/-/-/9  0x400645/0x4005ff/P/-/-/1  0x400637/0x400645/P/-/-/1  0x4005e9/0x400634/P/-/-/1  0x4005d7/0x4005e5/P/-/-/13  0x40062f/0x4005b0/P/-/-/9
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llvm/test/tools/llvm-profgen/cs-interrupt.test

 ;; The test fails on Windows. Fix it before removing the following requirement.
 ; REQUIRES: x86_64-linux
-; RUN: llvm-profgen --format=text --perfscript=%S/Inputs/cs-interrupt.perfscript --binary=%S/Inputs/noinline-cs-noprobe.perfbin --output=%t --show-unwinder-output --profile-summary-cold-count=0 | FileCheck %s --check-prefix=CHECK-UNWINDER
+; RUN: llvm-profgen --format=text --perfscript=%S/Inputs/cs-interrupt.perfscript --binary=%S/Inputs/noinline-cs-noprobe.perfbin --output=%t --skip-symbolization --profile-summary-cold-count=0
+; RUN: FileCheck %s --input-file %t --check-prefix=CHECK-UNWINDER
+; RUN: llvm-profgen --format=text --perfscript=%S/Inputs/cs-interrupt.perfscript --binary=%S/Inputs/noinline-cs-noprobe.perfbin --output=%t --profile-summary-cold-count=0
+>>>>>>> 02ea7084c370 ([llvm-profgen] Support LBR only perf script)
 ; RUN: FileCheck %s --input-file %t
 
 ; CHECK:[main:1 @ foo]:88:0
 ; CHECK: 2: 5
 ; CHECK: 3: 5 bar:5
 ; CHECK:[main:1 @ foo:3 @ bar]:74:5
 ; CHECK: 0: 5
 ; CHECK: 1: 5

llvm/test/tools/llvm-profgen/inline-cs-noprobe.test

-; RUN: llvm-profgen --format=text --perfscript=%S/Inputs/inline-cs-noprobe.perfscript --binary=%S/Inputs/inline-cs-noprobe.perfbin --output=%t --show-unwinder-output --profile-summary-cold-count=0 | FileCheck %s --check-prefix=CHECK-UNWINDER
+; RUN: llvm-profgen --format=text --perfscript=%S/Inputs/inline-cs-noprobe.perfscript --binary=%S/Inputs/inline-cs-noprobe.perfbin --output=%t --skip-symbolization --profile-summary-cold-count=0
+| FileCheck %s --input-file %t --check-prefix=CHECK-UNWINDER
+; RUN: llvm-profgen --format=text --perfscript=%S/Inputs/inline-cs-noprobe.perfscript --binary=%S/Inputs/inline-cs-noprobe.perfbin --output=%t --profile-summary-cold-count=0
 ; RUN: FileCheck %s --input-file %t
 
 ; CHECK:[main:1 @ foo]:309:0
 ; CHECK: 2.1: 14
 ; CHECK: 3: 15
 ; CHECK: 3.1: 14 bar:14
 ; CHECK: 3.2: 1
 ; CHECK:[main:1 @ foo:3.1 @ bar]:84:0

llvm/test/tools/llvm-profgen/inline-cs-pseudoprobe.test

-; RUN: llvm-profgen --format=text --perfscript=%S/Inputs/inline-cs-pseudoprobe.perfscript --binary=%S/Inputs/inline-cs-pseudoprobe.perfbin --output=%t --show-unwinder-output --profile-summary-cold-count=0 | FileCheck %s --check-prefix=CHECK-UNWINDER
+; RUN: llvm-profgen --format=text --perfscript=%S/Inputs/inline-cs-pseudoprobe.perfscript --binary=%S/Inputs/inline-cs-pseudoprobe.perfbin --output=%t --skip-symbolization --profile-summary-cold-count=0
+; RUN: FileCheck %s --input-file %t --check-prefix=CHECK-UNWINDER
+; RUN: llvm-profgen --format=text --perfscript=%S/Inputs/inline-cs-pseudoprobe.perfscript --binary=%S/Inputs/inline-cs-pseudoprobe.perfbin --output=%t --profile-summary-cold-count=0
 ; RUN: FileCheck %s --input-file %t
 
 ; CHECK:     [main:2 @ foo]:74:0
 ; CHECK-NEXT: 1: 0
 ; CHECK-NEXT: 2: 15
 ; CHECK-NEXT: 3: 15
 ; CHECK-NEXT: 4: 14
 ; CHECK-NEXT: 5: 1

llvm/test/tools/llvm-profgen/noinline-cs-noprobe.test

 ;; The test fails on Windows. Fix it before removing the following requirement.
 ; REQUIRES: x86_64-linux
-; RUN: llvm-profgen --format=text --perfscript=%S/Inputs/noinline-cs-noprobe.perfscript --binary=%S/Inputs/noinline-cs-noprobe.perfbin --output=%t --show-unwinder-output --profile-summary-cold-count=0 | FileCheck %s --check-prefix=CHECK-UNWINDER
+; RUN: llvm-profgen --format=text --perfscript=%S/Inputs/noinline-cs-noprobe.perfscript --binary=%S/Inputs/noinline-cs-noprobe.perfbin --output=%t --skip-symbolization --profile-summary-cold-count=0
+; RUN: FileCheck %s --input-file %t --check-prefix=CHECK-UNWINDER
+; RUN: llvm-profgen --format=text --perfscript=%S/Inputs/noinline-cs-noprobe.perfscript --binary=%S/Inputs/noinline-cs-noprobe.perfbin --output=%t --profile-summary-cold-count=0
 ; RUN: FileCheck %s --input-file %t
-; RUN: llvm-profgen --format=text --perfscript=%S/Inputs/noinline-cs-noprobe.aggperfscript --binary=%S/Inputs/noinline-cs-noprobe.perfbin --output=%t --show-unwinder-output --profile-summary-cold-count=0 | FileCheck %s --check-prefix=CHECK-AGG-UNWINDER
+; RUN: llvm-profgen --format=text --perfscript=%S/Inputs/noinline-cs-noprobe.aggperfscript --binary=%S/Inputs/noinline-cs-noprobe.perfbin --output=%t --skip-symbolization --profile-summary-cold-count=0
+; RUN: FileCheck %s --input-file %t --check-prefix=CHECK-AGG-UNWINDER
+; RUN: llvm-profgen --format=text --perfscript=%S/Inputs/noinline-cs-noprobe.aggperfscript --binary=%S/Inputs/noinline-cs-noprobe.perfbin --output=%t --profile-summary-cold-count=0
 ; RUN: FileCheck %s --input-file %t --check-prefix=CHECK-AGG
 
+
 ; CHECK-AGG:[main:1 @ foo]:108:0
 ; CHECK-AGG: 2: 6
 ; CHECK-AGG: 3: 6 bar:6
 ; CHECK-AGG:[main:1 @ foo:3 @ bar]:100:6
 ; CHECK-AGG: 0: 6
 ; CHECK-AGG: 1: 6
 ; CHECK-AGG: 2: 4
 ; CHECK-AGG: 4: 2

llvm/test/tools/llvm-profgen/noinline-cs-pseudoprobe.test

-; RUN: llvm-profgen --format=text --perfscript=%S/Inputs/noinline-cs-pseudoprobe.perfscript --binary=%S/Inputs/noinline-cs-pseudoprobe.perfbin --output=%t --show-unwinder-output --profile-summary-cold-count=0 | FileCheck %s --check-prefix=CHECK-UNWINDER
+; RUN: llvm-profgen --format=text --perfscript=%S/Inputs/noinline-cs-pseudoprobe.perfscript --binary=%S/Inputs/noinline-cs-pseudoprobe.perfbin --output=%t --skip-symbolization --profile-summary-cold-count=0
+; RUN: FileCheck %s --input-file %t --check-prefix=CHECK-UNWINDER
+; RUN: llvm-profgen --format=text --perfscript=%S/Inputs/noinline-cs-pseudoprobe.perfscript --binary=%S/Inputs/noinline-cs-pseudoprobe.perfbin --output=%t --profile-summary-cold-count=0
 ; RUN: FileCheck %s --input-file %t
-; RUN: llvm-profgen --format=text --perfscript=%S/Inputs/noinline-cs-pseudoprobe.aggperfscript --binary=%S/Inputs/noinline-cs-pseudoprobe.perfbin --output=%t --show-unwinder-output --profile-summary-cold-count=0 | FileCheck %s --check-prefix=CHECK-UNWINDER
+; RUN: llvm-profgen --format=text --perfscript=%S/Inputs/noinline-cs-pseudoprobe.aggperfscript --binary=%S/Inputs/noinline-cs-pseudoprobe.perfbin --output=%t --skip-symbolization --profile-summary-cold-count=0
+; RUN: FileCheck %s --input-file %t --check-prefix=CHECK-UNWINDER
+; RUN: llvm-profgen --format=text --perfscript=%S/Inputs/noinline-cs-pseudoprobe.aggperfscript --binary=%S/Inputs/noinline-cs-pseudoprobe.perfbin --output=%t --profile-summary-cold-count=0
 ; RUN: FileCheck %s --input-file %t
 
 
 ; CHECK:     [main:2 @ foo]:75:0
 ; CHECK-NEXT: 1: 0
 ; CHECK-NEXT: 2: 15
 ; CHECK-NEXT: 3: 15
 ; CHECK-NEXT: 4: 15

llvm/test/tools/llvm-profgen/noprobe.test

+; RUN: llvm-profgen --format=text --perfscript=%S/Inputs/noprobe.perfscript --binary=%S/Inputs/noprobe.perfbin --output=%t --skip-symbolization
+; RUN: FileCheck %s --input-file %t --check-prefix=CHECK-RAW-PROFILE
+; RUN: llvm-profgen --format=text --perfscript=%S/Inputs/noprobe.mmap.perfscript --binary=%S/Inputs/noprobe.perfbin --output=%t --skip-symbolization
+; RUN: FileCheck %s --input-file %t --check-prefix=CHECK-RAW-PROFILE
+; RUN: llvm-profgen --format=text --perfscript=%S/Inputs/noprobe.aggperfscript --binary=%S/Inputs/noprobe.perfbin --output=%t --skip-symbolization
+; RUN: FileCheck %s --input-file %t --check-prefix=CHECK-RAW-PROFILE-AGG
+
+CHECK-RAW-PROFILE:      7
+CHECK-RAW-PROFILE-NEXT: 5b0-5c8:7
+CHECK-RAW-PROFILE-NEXT: 5b0-5d7:13
+CHECK-RAW-PROFILE-NEXT: 5dc-5e9:6
+CHECK-RAW-PROFILE-NEXT: 5e5-5e9:12
+CHECK-RAW-PROFILE-NEXT: 5ff-62f:19
+CHECK-RAW-PROFILE-NEXT: 634-637:18
+CHECK-RAW-PROFILE-NEXT: 645-645:18
+CHECK-RAW-PROFILE-NEXT: 6
+CHECK-RAW-PROFILE-NEXT: 5c8->5dc:7
+CHECK-RAW-PROFILE-NEXT: 5d7->5e5:13
+CHECK-RAW-PROFILE-NEXT: 5e9->634:18
+CHECK-RAW-PROFILE-NEXT: 62f->5b0:21
+CHECK-RAW-PROFILE-NEXT: 637->645:18
+CHECK-RAW-PROFILE-NEXT: 645->5ff:19
+
+
+CHECK-RAW-PROFILE-AGG:      7
+CHECK-RAW-PROFILE-AGG-NEXT: 5b0-5c8:13
+CHECK-RAW-PROFILE-AGG-NEXT: 5b0-5d7:21
+CHECK-RAW-PROFILE-AGG-NEXT: 5dc-5e9:10
+CHECK-RAW-PROFILE-AGG-NEXT: 5e5-5e9:20
+CHECK-RAW-PROFILE-AGG-NEXT: 5ff-62f:31
+CHECK-RAW-PROFILE-AGG-NEXT: 634-637:30
+CHECK-RAW-PROFILE-AGG-NEXT: 645-645:30
+CHECK-RAW-PROFILE-AGG-NEXT: 6
+CHECK-RAW-PROFILE-AGG-NEXT: 5c8->5dc:13
+CHECK-RAW-PROFILE-AGG-NEXT: 5d7->5e5:21
+CHECK-RAW-PROFILE-AGG-NEXT: 5e9->634:30
+CHECK-RAW-PROFILE-AGG-NEXT: 62f->5b0:35
+CHECK-RAW-PROFILE-AGG-NEXT: 637->645:30
+CHECK-RAW-PROFILE-AGG-NEXT: 645->5ff:31
+
+
+; original code:
+; clang -O3 -g -debug-info-for-profiling test.c -o a.out
+#include <stdio.h>
+
+int bar(int x, int y) {
+  if (x % 3) {
+    return x - y;
+  }
+  return x + y;
+}
+
+void foo() {
+  int s, i = 0;
+  while (i++ < 4000 * 4000)
+    if (i % 91) s = bar(i, s); else s += 30;
+  printf("sum is %d\n", s);
+}
+
+int main() {
+  foo();
+  return 0;
+}

llvm/test/tools/llvm-profgen/recursion-compression-pseudoprobe.test

 ; Firstly test uncompression(--compress-recursion=0)
 ; RUN: llvm-profgen --format=text --perfscript=%S/Inputs/recursion-compression-pseudoprobe.perfscript --binary=%S/Inputs/recursion-compression-pseudoprobe.perfbin --output=%t --compress-recursion=0 --profile-summary-cold-count=0
 ; RUN: FileCheck %s --input-file %t -check-prefix=CHECK-UNCOMPRESS
-; RUN: llvm-profgen --format=text --perfscript=%S/Inputs/recursion-compression-pseudoprobe.perfscript --binary=%S/Inputs/recursion-compression-pseudoprobe.perfbin --output=%t --show-unwinder-output --profile-summary-cold-count=0 | FileCheck %s --check-prefix=CHECK-UNWINDER
+; RUN: llvm-profgen --format=text --perfscript=%S/Inputs/recursion-compression-pseudoprobe.perfscript --binary=%S/Inputs/recursion-compression-pseudoprobe.perfbin --output=%t --skip-symbolization --profile-summary-cold-count=0
+; RUN: FileCheck %s --input-file %t --check-prefix=CHECK-UNWINDER
+; RUN: llvm-profgen --format=text --perfscript=%S/Inputs/recursion-compression-pseudoprobe.perfscript --binary=%S/Inputs/recursion-compression-pseudoprobe.perfbin --output=%t --profile-summary-cold-count=0
 ; RUN: FileCheck %s --input-file %t
-; RUN: llvm-profgen --format=text --perfscript=%S/Inputs/recursion-compression-pseudoprobe-nommap.perfscript --binary=%S/Inputs/recursion-compression-pseudoprobe.perfbin --output=%t --show-unwinder-output --profile-summary-cold-count=0 | FileCheck %s --check-prefix=CHECK-UNWINDER
+; RUN: llvm-profgen --format=text --perfscript=%S/Inputs/recursion-compression-pseudoprobe-nommap.perfscript --binary=%S/Inputs/recursion-compression-pseudoprobe.perfbin --output=%t --skip-symbolization --profile-summary-cold-count=0
+; RUN: FileCheck %s --input-file %t --check-prefix=CHECK-UNWINDER
+; RUN: llvm-profgen --format=text --perfscript=%S/Inputs/recursion-compression-pseudoprobe-nommap.perfscript --binary=%S/Inputs/recursion-compression-pseudoprobe.perfbin --output=%t --profile-summary-cold-count=0
 ; RUN: FileCheck %s --input-file %t
 ; RUN: llvm-profgen --format=text --perfscript=%S/Inputs/recursion-compression-pseudoprobe.perfscript --binary=%S/Inputs/recursion-compression-pseudoprobe.perfbin --output=%t --compress-recursion=0 --profile-summary-cold-count=0 --csprof-max-context-depth=0
 ; RUN: FileCheck %s --input-file %t -check-prefix=CHECK-MAX-CTX-DEPTH
 
 
 ; CHECK-UNCOMPRESS: [main:2 @ foo:5 @ fa:8 @ fa:7 @ fb:5 @ fb:5 @ fb:5 @ fb:5 @ fb:5 @ fb:5 @ fb:5 @ fb:5 @ fb:6 @ fa]:4:1
 ; CHECK-UNCOMPRESS:  1: 1
 ; CHECK-UNCOMPRESS:  3: 1

llvm/tools/llvm-profgen/PerfReader.h

 public:
   std::shared_ptr<T> Data;
   Hashable(const std::shared_ptr<T> &D) : Data(D) {}
 
   // Hash code generation
   struct Hash {
     uint64_t operator()(const Hashable<T> &Key) const {
       // Don't make it virtual for getHashCode
-      assert(Key.Data->getHashCode() && "Should generate HashCode for it!");
-      return Key.Data->getHashCode();
+      uint64_t Hash = Key.Data->getHashCode();
+      assert(Hash && "Should generate HashCode for it!");
+      return Hash;
     }
   };
 
   // Hash equal
   struct Equal {
     bool operator()(const Hashable<T> &LHS, const Hashable<T> &RHS) const {
       // Precisely compare the data, vtable will have overhead.
       return LHS.Data->isEqual(RHS.Data.get());
     }
   };
 
   T *getPtr() const { return Data.get(); }
 };
 
-// Base class to extend for all types of perf sample
 struct PerfSample {
-  uint64_t HashCode = 0;
+  // LBR stack recorded in FIFO order.
+  SmallVector<LBREntry, 16> LBRStack;
+  // Call stack recorded in FILO(leaf to root) order, it's used for CS-profile
+  // generation
+  SmallVector<uint64_t, 16> CallStack;
 
   virtual ~PerfSample() = default;
-  uint64_t getHashCode() const { return HashCode; }
-  virtual bool isEqual(const PerfSample *K) const {
-    return HashCode == K->HashCode;
-  };
-
-  // Utilities for LLVM-style RTTI
-  enum PerfKind { PK_HybridSample };
-  const PerfKind Kind;
-  PerfKind getKind() const { return Kind; }
-  PerfSample(PerfKind K) : Kind(K){};
+  uint64_t getHashCode() const {
+    // Use simple DJB2 hash
+    auto HashCombine = [](uint64_t H, uint64_t V) {
+      return ((H << 5) + H) + V;
     };
-
-// The parsed hybrid sample including call stack and LBR stack.
-struct HybridSample : public PerfSample {
-  // Profiled binary that current frame address belongs to
-  ProfiledBinary *Binary;
-  // Call stack recorded in FILO(leaf to root) order
-  SmallVector<uint64_t, 16> CallStack;
-  // LBR stack recorded in FIFO order
-  SmallVector<LBREntry, 16> LBRStack;
-
-  HybridSample(ProfiledBinary *B) : PerfSample(PK_HybridSample), Binary(B){};
-  static bool classof(const PerfSample *K) {
-    return K->getKind() == PK_HybridSample;
+    uint64_t Hash = 5381;
+    for (const auto &Value : CallStack) {
+      Hash = HashCombine(Hash, Value);
+    }
+    for (const auto &Entry : LBRStack) {
+      Hash = HashCombine(Hash, Entry.Source);
+      Hash = HashCombine(Hash, Entry.Target);
+    }
+    return Hash;
   }
 
-  // Used for sample aggregation
-  bool isEqual(const PerfSample *K) const override {
-    const HybridSample *Other = dyn_cast<HybridSample>(K);
-    if (Other->Binary != Binary)
-      return false;
+  bool isEqual(const PerfSample *Other) const {
     const SmallVector<uint64_t, 16> &OtherCallStack = Other->CallStack;
     const SmallVector<LBREntry, 16> &OtherLBRStack = Other->LBRStack;
 
     if (CallStack.size() != OtherCallStack.size() ||
         LBRStack.size() != OtherLBRStack.size())
       return false;
 
-    auto Iter = CallStack.begin();
-    for (auto Address : OtherCallStack) {
-      if (Address != *Iter++)
-        return false;
-    }
+    if (!std::equal(CallStack.begin(), CallStack.end(), OtherCallStack.begin()))
 
     for (size_t I = 0; I < OtherLBRStack.size(); I++) {
       if (LBRStack[I].Source != OtherLBRStack[I].Source ||
           LBRStack[I].Target != OtherLBRStack[I].Target)
         return false;
     }
     return true;
   }
 
-  void genHashCode() {
-    // Use simple DJB2 hash
-    auto HashCombine = [](uint64_t H, uint64_t V) {
-      return ((H << 5) + H) + V;
-    };
-    uint64_t Hash = 5381;
-    Hash = HashCombine(Hash, reinterpret_cast<uint64_t>(Binary));
-    for (const auto &Value : CallStack) {
-      Hash = HashCombine(Hash, Value);
-    }
-    for (const auto &Entry : LBRStack) {
-      Hash = HashCombine(Hash, Entry.Source);
-      Hash = HashCombine(Hash, Entry.Target);
-    }
-    HashCode = Hash;
-  }
-
 #ifndef NDEBUG
   void print() const {
     dbgs() << "LBR stack\n";
     printLBRStack(LBRStack);
     dbgs() << "Call stack\n";
     printCallStack(CallStack);
   }
 #endif
 };
-
 // After parsing the sample, we record the samples by aggregating them
 // into this counter. The key stores the sample data and the value is
 // the sample repeat times.
 using AggregatedCounter =
     std::unordered_map<Hashable<PerfSample>, uint64_t,
                        Hashable<PerfSample>::Hash, Hashable<PerfSample>::Equal>;
 
 using SampleVector = SmallVector<std::tuple<uint64_t, uint64_t, uint64_t>, 16>;
struct ProfiledFrame {
     bool isDummyRoot() { return Address == 0; }
     bool isLeafFrame() { return Children.empty(); }
   };
 
   ProfiledFrame DummyTrieRoot;
   ProfiledFrame *CurrentLeafFrame;
   // Used to fall through the LBR stack
   uint32_t LBRIndex = 0;
-  // Reference to HybridSample.LBRStack
+  // Reference to PerfSample.LBRStack
   const SmallVector<LBREntry, 16> &LBRStack;
   // Used to iterate the address range
   InstructionPointer InstPtr;
-  UnwindState(const HybridSample *Sample)
-      : Binary(Sample->Binary), LBRStack(Sample->LBRStack),
-        InstPtr(Sample->Binary, Sample->CallStack.front()) {
+  UnwindState(const PerfSample *Sample, const ProfiledBinary *Binary)
+      : Binary(Binary), LBRStack(Sample->LBRStack),
+        InstPtr(Binary, Sample->CallStack.front()) {
     initFrameTrie(Sample->CallStack);
   }
 
   bool validateInitialState() {
     uint64_t LBRLeaf = LBRStack[LBRIndex].Target;
     uint64_t LeafAddr = CurrentLeafFrame->Address;
     // When we take a stack sample, ideally the sampling distance between the
     // leaf IP of stack and the last LBR target shouldn't be very large.

 using BranchSample = std::map<std::pair<uint64_t, uint64_t>, uint64_t>;
 // The counter of range samples for one function indexed by the range,
 // which is represented as the start and end offset pair.
 using RangeSample = std::map<std::pair<uint64_t, uint64_t>, uint64_t>;
 // Wrapper for sample counters including range counter and branch counter
 struct SampleCounter {
   RangeSample RangeCounter;
   BranchSample BranchCounter;
 
   void recordRangeCount(uint64_t Start, uint64_t End, uint64_t Repeat) {
     RangeCounter[{Start, End}] += Repeat;
   }
   void recordBranchCount(uint64_t Source, uint64_t Target, uint64_t Repeat) {
     BranchCounter[{Source, Target}] += Repeat;
   }
 };
 

 splitting and record counters by the range with same inline context. Over those
 unwinding process we will record each call stack as context id and LBR/linear
 range as sample counter for further CS profile generation.
 */
 class VirtualUnwinder {
 public:
   VirtualUnwinder(ContextSampleCounterMap *Counter, const ProfiledBinary *B)
       : CtxCounterMap(Counter), Binary(B) {}
-  bool unwind(const HybridSample *Sample, uint64_t Repeat);
+  bool unwind(const PerfSample *Sample, uint64_t Repeat);
 
 private:
   bool isCallState(UnwindState &State) const {
     // The tail call frame is always missing here in stack sample, we will
     // use a specific tail call tracker to infer it.
     return Binary->addressIsCall(State.getCurrentLBRSource());
   }
 
PerfReaderBase(ProfiledBinary *B) : Binary(B) {
     // Initialize the base address to preferred address.
     Binary->setBaseAddress(Binary->getPreferredBaseAddress());
   };
   virtual ~PerfReaderBase() = default;
   static std::unique_ptr<PerfReaderBase>
   create(ProfiledBinary *Binary, cl::list<std::string> &PerfTraceFilenames);
 
   // A LBR sample is like:
-  // 0x5c6313f/0x5c63170/P/-/-/0  0x5c630e7/0x5c63130/P/-/-/0 ...
+  // 40062f 0x5c6313f/0x5c63170/P/-/-/0  0x5c630e7/0x5c63130/P/-/-/0 ...
   // A heuristic for fast detection by checking whether a
   // leading "  0x" and the '/' exist.
   static bool isLBRSample(StringRef Line) {
-    if (!Line.startswith(" 0x"))
+    // Skip the leading instruction pointer
+    SmallVector<StringRef, 32> Records;
+    Line.trim().split(Records, " ", 2, false);
+    if (Records.size() < 2)
       return false;
-    if (Line.find('/') != StringRef::npos)
+    if (Records[1].startswith("0x") && Records[1].find('/') != StringRef::npos)
       return true;
     return false;
   }
 
   // The raw hybird sample is like
   // e.g.
   //            4005dc    # call stack leaf
   //            400634
   //            400684    # call stack root
   // 0x4005c8/0x4005dc/P/-/-/0   0x40062f/0x4005b0/P/-/-/0 ...
   //          ... 0x4005c8/0x4005dc/P/-/-/0    # LBR Entries
   // Determine the perfscript contains hybrid samples(call stack + LBRs) by
   // checking whether there is a non-empty call stack immediately followed by
   // a LBR sample
   static PerfScriptType checkPerfScriptType(StringRef FileName) {
     TraceStream TraceIt(FileName);
     uint64_t FrameAddr = 0;
     while (!TraceIt.isAtEoF()) {
+      // Skip the aggregated count
+      if (!TraceIt.getCurrentLine().getAsInteger(10, FrameAddr))
+        TraceIt.advance();
+
+      // Detect sample with call stack
       int32_t Count = 0;
       while (!TraceIt.isAtEoF() &&
              !TraceIt.getCurrentLine().ltrim().getAsInteger(16, FrameAddr)) {
         Count++;
         TraceIt.advance();
       }
       if (!TraceIt.isAtEoF()) {
         if (isLBRSample(TraceIt.getCurrentLine())) {
protected:
   /// Parse a single line of a PERF_RECORD_MMAP2 event looking for a
   /// mapping between the binary name and its memory layout.
   ///
   void parseMMap2Event(TraceStream &TraceIt);
   // Parse perf events/samples and do aggregation
   void parseAndAggregateTrace(StringRef Filename);
   // Parse either an MMAP event or a perf sample
   void parseEventOrSample(TraceStream &TraceIt);
+  // Warn if the relevant mmap event is missing.
+  void warnIfMissingMMap();
   // Extract call stack from the perf trace lines
   bool extractCallstack(TraceStream &TraceIt,
                         SmallVectorImpl<uint64_t> &CallStack);
   // Extract LBR stack from one perf trace line
   bool extractLBRStack(TraceStream &TraceIt,
                        SmallVectorImpl<LBREntry> &LBRStack);
   uint64_t parseAggregatedCount(TraceStream &TraceIt);
   // Parse one sample from multiple perf lines, override this for different
   // sample type
   void parseSample(TraceStream &TraceIt);
   // An aggregated count is given to indicate how many times the sample is
   // repeated.
   virtual void parseSample(TraceStream &TraceIt, uint64_t Count) = 0;
   // Post process the profile after trace aggregation, we will do simple range
   // overlap computation for AutoFDO, or unwind for CSSPGO(hybrid sample).
   virtual void generateRawProfile() = 0;
+  virtual void writeRawProfile(StringRef Filename);
+  virtual void writeRawProfile(raw_fd_ostream &OS) = 0;
 
   ProfiledBinary *Binary = nullptr;
 
   ContextSampleCounterMap SampleCounters;
   // Samples with the repeating time generated by the perf reader
   AggregatedCounter AggregatedSamples;
   PerfScriptType PerfType = PERF_UNKNOWN;
 };
public:
   };
   // Parse the hybrid sample including the call and LBR line
   void parseSample(TraceStream &TraceIt, uint64_t Count) override;
   void generateRawProfile() override;
 
 private:
   // Unwind the hybrid samples after aggregration
   void unwindSamples();
-  void printUnwinderOutput();
+  void writeRawProfile(raw_fd_ostream &OS) override;
+};
+
+/*
+  The reader of LBR only perf script.
+  A typical LBR sample is like:
+    40062f 0x4005c8/0x4005dc/P/-/-/0   0x40062f/0x4005b0/P/-/-/0 ...
+          ... 0x4005c8/0x4005dc/P/-/-/0
+*/
+class LBRPerfReader : public PerfReaderBase {
+public:
+  LBRPerfReader(ProfiledBinary *Binary) : PerfReaderBase(Binary) {
+    // There is no context for LBR only sample, so initialize one entry with
+    // fake "empty" context key.
+    std::shared_ptr<StringBasedCtxKey> Key =
+        std::make_shared<StringBasedCtxKey>();
+    Key->genHashCode();
+    SampleCounters.emplace(Hashable<ContextKey>(Key), SampleCounter());
+    PerfType = PERF_LBR;
+  };
+
+  // Parse the LBR only sample.
+  void parseSample(TraceStream &TraceIt, uint64_t Count) override;
+  void generateRawProfile() override;
+
+private:
+  void computeCounterFromLBR(const PerfSample *Sample, uint64_t Repeat);
+  void writeRawProfile(raw_fd_ostream &OS) override;
 };
 
 } // end namespace sampleprof
 } // end namespace llvm
 
 #endif

llvm/tools/llvm-profgen/PerfReader.cpp

 //===-- PerfReader.cpp - perfscript reader  ---------------------*- C++ -*-===//
 //
 // 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
 //
 //===----------------------------------------------------------------------===//
 #include "PerfReader.h"
 #include "ProfileGenerator.h"
+#include "llvm/Support/FileSystem.h"
 
 static cl::opt<bool> ShowMmapEvents("show-mmap-events", cl::ReallyHidden,
                                     cl::init(false), cl::ZeroOrMore,
                                     cl::desc("Print binary load events."));
 
-static cl::opt<bool> ShowUnwinderOutput("show-unwinder-output",
-                                        cl::ReallyHidden, cl::init(false),
-                                        cl::ZeroOrMore,
-                                        cl::desc("Print unwinder output"));
+cl::opt<bool> SkipSymbolization("skip-symbolization", cl::ReallyHidden,
+                                cl::init(false), cl::ZeroOrMore,
+                                cl::desc("Dump the unsumbolized profile to the "
+                                         "output file. It will show unwinder "
+                                         "output for CS profile generation."));
 
 extern cl::opt<bool> ShowDisassemblyOnly;
 extern cl::opt<bool> ShowSourceLocations;
+extern cl::opt<std::string> OutputFilename;
 
 namespace llvm {
 namespace sampleprof {
 
 void VirtualUnwinder::unwindCall(UnwindState &State) {
   // The 2nd frame after leaf could be missing if stack sample is
   // taken when IP is within prolog/epilog, as frame chain isn't
   // setup yet. Fill in the missing frame in that case.
if (Binary->usePseudoProbes()) {
     State.getParentFrame()->recordBranchCount(Branch.Source, Branch.Target,
                                               Repeat);
   } else {
     State.CurrentLeafFrame->recordBranchCount(Branch.Source, Branch.Target,
                                               Repeat);
   }
 }
 
-bool VirtualUnwinder::unwind(const HybridSample *Sample, uint64_t Repeat) {
+bool VirtualUnwinder::unwind(const PerfSample *Sample, uint64_t Repeat) {
   // Capture initial state as starting point for unwinding.
-  UnwindState State(Sample);
+  UnwindState State(Sample, Binary);
 
   // Sanity check - making sure leaf of LBR aligns with leaf of stack sample
   // Stack sample sometimes can be unreliable, so filter out bogus ones.
   if (!State.validateInitialState())
     return false;
 
   // Also do not attempt linear unwind for the leaf range as it's incomplete.
   bool IsLeaf = true;

 std::unique_ptr<PerfReaderBase>
 PerfReaderBase::create(ProfiledBinary *Binary,
                        cl::list<std::string> &PerfTraceFilenames) {
   PerfScriptType PerfType = extractPerfType(PerfTraceFilenames);
   std::unique_ptr<PerfReaderBase> PerfReader;
   if (PerfType == PERF_LBR_STACK) {
     PerfReader.reset(new HybridPerfReader(Binary));
   } else if (PerfType == PERF_LBR) {
-    // TODO:
-    exitWithError("Unsupported perfscript!");
+    PerfReader.reset(new LBRPerfReader(Binary));
   } else {
     exitWithError("Unsupported perfscript!");
   }
 
   return PerfReader;
 }
 
 void PerfReaderBase::updateBinaryAddress(const MMapEvent &Event) {
if (It != Offsets.end() && *It == Event.Offset) {
       }
     }
   }
 }
 
 // Use ordered map to make the output deterministic
 using OrderedCounterForPrint = std::map<std::string, RangeSample>;
 
-static void printSampleCounter(OrderedCounterForPrint &OrderedCounter) {
+static void printSampleCounter(OrderedCounterForPrint &OrderedCounter,
+                               raw_fd_ostream &OS) {
   for (auto Range : OrderedCounter) {
-    outs() << Range.first << "\n";
+    OS << Range.first << "\n";
     for (auto I : Range.second) {
-      outs() << "  (" << format("%" PRIx64, I.first.first) << ", "
-             << format("%" PRIx64, I.first.second) << "): " << I.second << "\n";
+      OS << "  (" << format("%" PRIx64, I.first.first) << ", "
     }
   }
 }
 
 static std::string getContextKeyStr(ContextKey *K,
                                     const ProfiledBinary *Binary) {
   if (const auto *CtxKey = dyn_cast<StringBasedCtxKey>(K)) {
     return SampleContext::getContextString(CtxKey->Context);
   } else if (const auto *CtxKey = dyn_cast<ProbeBasedCtxKey>(K)) {
     SampleContextFrameVector ContextStack;
     for (const auto *Probe : CtxKey->Probes) {
       Binary->getInlineContextForProbe(Probe, ContextStack, true);
     }
     // Probe context key at this point does not have leaf probe, so do not
     // include the leaf inline location.
     return SampleContext::getContextString(ContextStack, true);
   } else {
     llvm_unreachable("unexpected key type");
   }
 }
 
 static void printRangeCounter(ContextSampleCounterMap &Counter,
-                              const ProfiledBinary *Binary) {
+                              const ProfiledBinary *Binary,
+                              raw_fd_ostream &OS) {
   OrderedCounterForPrint OrderedCounter;
   for (auto &CI : Counter) {
     OrderedCounter[getContextKeyStr(CI.first.getPtr(), Binary)] =
         CI.second.RangeCounter;
   }
-  printSampleCounter(OrderedCounter);
+  printSampleCounter(OrderedCounter, OS);
 }
 
 static void printBranchCounter(ContextSampleCounterMap &Counter,
-                               const ProfiledBinary *Binary) {
+                               const ProfiledBinary *Binary,
+                               raw_fd_ostream &OS) {
   OrderedCounterForPrint OrderedCounter;
   for (auto &CI : Counter) {
     OrderedCounter[getContextKeyStr(CI.first.getPtr(), Binary)] =
         CI.second.BranchCounter;
   }
-  printSampleCounter(OrderedCounter);
+  printSampleCounter(OrderedCounter, OS);
 }
 
-void HybridPerfReader::printUnwinderOutput() {
-    outs() << "Binary(" << Binary->getName().str() << ")'s Range Counter:\n";
-    printRangeCounter(SampleCounters, Binary);
-    outs() << "\nBinary(" << Binary->getName().str() << ")'s Branch Counter:\n";
-    printBranchCounter(SampleCounters, Binary);
+void HybridPerfReader::writeRawProfile(raw_fd_ostream &OS) {
+  OS << "Binary(" << Binary->getName().str() << ")'s Range Counter:\n";
+  printRangeCounter(SampleCounters, Binary, OS);
+  OS << "\nBinary(" << Binary->getName().str() << ")'s Branch Counter:\n";
+  printBranchCounter(SampleCounters, Binary, OS);
 }
 
 void HybridPerfReader::unwindSamples() {
   for (const auto &Item : AggregatedSamples) {
-    const HybridSample *Sample = dyn_cast<HybridSample>(Item.first.getPtr());
+    const PerfSample *Sample = Item.first.getPtr();
     VirtualUnwinder Unwinder(&SampleCounters, Binary);
     Unwinder.unwind(Sample, Item.second);
   }
 
-  if (ShowUnwinderOutput)
-    printUnwinderOutput();
+  if (SkipSymbolization)
+    PerfReaderBase::writeRawProfile(OutputFilename);
 }
 
 bool PerfReaderBase::extractLBRStack(TraceStream &TraceIt,
                                      SmallVectorImpl<LBREntry> &LBRStack) {
   // The raw format of LBR stack is like:
   // 0x4005c8/0x4005dc/P/-/-/0 0x40062f/0x4005b0/P/-/-/0 ...
   //                           ... 0x4005c8/0x4005dc/P/-/-/0
   // It's in FIFO order and seperated by whitespace.
   SmallVector<StringRef, 32> Records;
-  TraceIt.getCurrentLine().split(Records, " ");
+  TraceIt.getCurrentLine().split(Records, " ", -1, false);
 
-  // Extract leading instruction pointer if present, use single
-  // list to pass out as reference.
+  // Skip the leading instruction pointer.
   size_t Index = 0;
   if (!Records.empty() && Records[0].find('/') == StringRef::npos) {
     Index = 1;
   }
   // Now extract LBR samples - note that we do not reverse the
   // LBR entry order so we can unwind the sample stack as we walk
   // through LBR entries.
   uint64_t PrevTrDst = 0;
bool PerfReaderBase::extractCallstack(TraceStream &TraceIt,
   // out to reduce the number of different calling contexts. One instance
   // of such case - when sample landed in prolog/epilog, somehow stack
   // walking will be broken in an unexpected way that higher frames will be
   // missing.
   return !CallStack.empty() &&
          !Binary->addressInPrologEpilog(CallStack.front());
 }
 
+void PerfReaderBase::warnIfMissingMMap() {
+  if (!Binary->getMissingMMapWarned() && !Binary->getIsLoadedByMMap()) {
+    WithColor::warning() << "No relevant mmap event is matched, will use "
+                            "preferred address as the base loading address!\n";
+    // Avoid redundant warning, only warn at the first unmatched sample.
+    Binary->setMissingMMapWarned(true);
+  }
+}
+
 void HybridPerfReader::parseSample(TraceStream &TraceIt, uint64_t Count) {
   // The raw hybird sample started with call stack in FILO order and followed
   // intermediately by LBR sample
   // e.g.
   //            4005dc    # call stack leaf
   //            400634
   //            400684    # call stack root
   // 0x4005c8/0x4005dc/P/-/-/0   0x40062f/0x4005b0/P/-/-/0 ...
   //          ... 0x4005c8/0x4005dc/P/-/-/0    # LBR Entries
   //
-  std::shared_ptr<HybridSample> Sample = std::make_shared<HybridSample>(Binary);
+  std::shared_ptr<PerfSample> Sample = std::make_shared<PerfSample>();
 
-  // Parsing call stack and populate into HybridSample.CallStack
+  // Parsing call stack and populate into PerfSample.CallStack
   if (!extractCallstack(TraceIt, Sample->CallStack)) {
     // Skip the next LBR line matched current call stack
     if (!TraceIt.isAtEoF() && TraceIt.getCurrentLine().startswith(" 0x"))
       TraceIt.advance();
     return;
   }
 
-  if (!Binary->getMissingMMapWarned() && !Binary->getIsLoadedByMMap()) {
-    WithColor::warning() << "No relevant mmap event is matched, will use "
-                            "preferred address as the base loading address!\n";
-    // Avoid redundant warning, only warn at the first unmatched sample.
-    Binary->setMissingMMapWarned(true);
-  }
+  warnIfMissingMMap();
 
   if (!TraceIt.isAtEoF() && TraceIt.getCurrentLine().startswith(" 0x")) {
-    // Parsing LBR stack and populate into HybridSample.LBRStack
+    // Parsing LBR stack and populate into PerfSample.LBRStack
     if (extractLBRStack(TraceIt, Sample->LBRStack)) {
       // Canonicalize stack leaf to avoid 'random' IP from leaf frame skew LBR
       // ranges
       Sample->CallStack.front() = Sample->LBRStack[0].Target;
       // Record samples by aggregation
-      Sample->genHashCode();
       AggregatedSamples[Hashable<PerfSample>(Sample)] += Count;
     }
   } else {
     // LBR sample is encoded in single line after stack sample
     exitWithError("'Hybrid perf sample is corrupted, No LBR sample line");
   }
 }
 
+void PerfReaderBase::writeRawProfile(StringRef Filename) {
+  std::error_code EC;
+  raw_fd_ostream OS(Filename, EC, llvm::sys::fs::OF_TextWithCRLF);
+  if (EC)
+    exitWithError(EC, Filename);
+  writeRawProfile(OS);
+}
+
+void LBRPerfReader::writeRawProfile(raw_fd_ostream &OS) {
+  /*
+     Format:
+     number of entries in RangeCounter
+     from_1-to_1:count_1
+     from_2-to_2:count_2
+     ......
+     from_n-to_n:count_n
+     number of entries in BranchCounter
+     src_1->dst_1:count_1
+     src_2->dst_2:count_2
+     ......
+     src_n->dst_n:count_n
+  */
+
+  SampleCounter &Counter = SampleCounters.begin()->second;
+  OS << Counter.RangeCounter.size() << "\n";
+  for (auto I : Counter.RangeCounter) {
+    OS << Twine::utohexstr(I.first.first) << "-"
+       << Twine::utohexstr(I.first.second) << ":" << I.second << "\n";
+  }
+
+  OS << Counter.BranchCounter.size() << "\n";
+  for (auto I : Counter.BranchCounter) {
+    OS << Twine::utohexstr(I.first.first) << "->"
+       << Twine::utohexstr(I.first.second) << ":" << I.second << "\n";
+  }
+}
+
+void LBRPerfReader::computeCounterFromLBR(const PerfSample *Sample,
+                                          uint64_t Repeat) {
+  SampleCounter &Counter = SampleCounters.begin()->second;
+  uint64_t EndOffeset = 0;
+  for (const LBREntry &LBR : Sample->LBRStack) {
+    uint64_t SourceOffset = Binary->virtualAddrToOffset(LBR.Source);
+    uint64_t TargetOffset = Binary->virtualAddrToOffset(LBR.Target);
+
+    if (!LBR.IsArtificial) {
+      Counter.recordBranchCount(SourceOffset, TargetOffset, Repeat);
+    }
+
+    // If this not the first LBR, update the range count between TO of current
+    // LBR and FROM of next LBR.
+    uint64_t StartOffset = TargetOffset;
+    if (EndOffeset != 0) {
+      assert(StartOffset <= EndOffeset &&
+             "Bogus range should be filtered ealier!");
+      Counter.recordRangeCount(StartOffset, EndOffeset, Repeat);
+    }
+    EndOffeset = SourceOffset;
+  }
+}
+
+void LBRPerfReader::parseSample(TraceStream &TraceIt, uint64_t Count) {
+  std::shared_ptr<PerfSample> Sample = std::make_shared<PerfSample>();
+  // Parsing LBR stack and populate into PerfSample.LBRStack
+  if (extractLBRStack(TraceIt, Sample->LBRStack)) {
+    warnIfMissingMMap();
+    // Record LBR only samples by aggregation
+    AggregatedSamples[Hashable<PerfSample>(Sample)] += Count;
+  }
+}
+
+void LBRPerfReader::generateRawProfile() {
+  assert(SampleCounters.size() == 1 && "Must have one entry of sample counter");
+  for (const auto &Item : AggregatedSamples) {
+    const PerfSample *Sample = Item.first.getPtr();
+    computeCounterFromLBR(Sample, Item.second);
+  }
+
+  if (SkipSymbolization)
+    PerfReaderBase::writeRawProfile(OutputFilename);
+}
+
 uint64_t PerfReaderBase::parseAggregatedCount(TraceStream &TraceIt) {
   // The aggregated count is optional, so do not skip the line and return 1 if
   // it's unmatched
   uint64_t Count = 1;
   if (!TraceIt.getCurrentLine().getAsInteger(10, Count))
     TraceIt.advance();
   return Count;
 }
 
 void PerfReaderBase::parseSample(TraceStream &TraceIt) {
   uint64_t Count = parseAggregatedCount(TraceIt);
   assert(Count >= 1 && "Aggregated count should be >= 1!");
   parseSample(TraceIt, Count);
 }

llvm/tools/llvm-profgen/ProfileGenerator.cpp

 //===-- ProfileGenerator.cpp - Profile Generator  ---------------*- C++ -*-===//
 //
 // 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
 //
 //===----------------------------------------------------------------------===//
 
 #include "ProfileGenerator.h"
 #include "ProfiledBinary.h"
 #include "llvm/ProfileData/ProfileCommon.h"
 #include <unordered_set>
 
-static cl::opt<std::string> OutputFilename("output", cl::value_desc("output"),
-                                           cl::Required,
-                                           cl::desc("Output profile file"));
+cl::opt<std::string> OutputFilename("output", cl::value_desc("output"),
 static cl::alias OutputA("o", cl::desc("Alias for --output"),
                          cl::aliasopt(OutputFilename));
 
 static cl::opt<SampleProfileFormat> OutputFormat(
     "format", cl::desc("Format of output profile"), cl::init(SPF_Ext_Binary),
     cl::values(
         clEnumValN(SPF_Binary, "binary", "Binary encoding (default)"),
         clEnumValN(SPF_Compact_Binary, "compbinary", "Compact binary encoding"),

llvm/tools/llvm-profgen/ProfiledBinary.h

 using namespace llvm::object;
 
 namespace llvm {
 namespace sampleprof {
 
 class ProfiledBinary;
 
 struct InstructionPointer {
-  ProfiledBinary *Binary;
+  const ProfiledBinary *Binary;
   union {
     // Offset of the executable segment of the binary.
     uint64_t Offset = 0;
     // Also used as address in unwinder
     uint64_t Address;
   };
   // Index to the sorted code address array of the binary.
   uint64_t Index = 0;
-  InstructionPointer(ProfiledBinary *Binary, uint64_t Address,
+  InstructionPointer(const ProfiledBinary *Binary, uint64_t Address,
                      bool RoundToNext = false);
   void advance();
   void backward();
   void update(uint64_t Addr);
 };
 
 // PrologEpilog offset tracker, used to filter out broken stack samples
 // Currently we use a heuristic size (two) to infer prolog and epilog

llvm/tools/llvm-profgen/ProfiledBinary.cpp

for (int32_t I = InlineStack.getNumberOfFrames() - 1; I >= 0; I--) {
     LineLocation Line(LineOffset, Discriminator);
     auto It = NameStrings.insert(FunctionName.str());
     CallStack.emplace_back(*It.first, Line);
   }
 
   return CallStack;
 }
 
-InstructionPointer::InstructionPointer(ProfiledBinary *Binary, uint64_t Address,
-                                       bool RoundToNext)
+InstructionPointer::InstructionPointer(const ProfiledBinary *Binary,
+                                       uint64_t Address, bool RoundToNext)
     : Binary(Binary), Address(Address) {
   Index = Binary->getIndexForAddr(Address);
   if (RoundToNext) {
     // we might get address which is not the code
     // it should round to the next valid address
     this->Address = Binary->getAddressforIndex(Index);
   }
 }

llvm/tools/llvm-profgen/llvm-profgen.cpp

 
 static cl::opt<std::string> BinaryPath(
     "binary", cl::value_desc("binary"), cl::Required,
     cl::desc("Path of profiled binary, only one binary is supported."),
     cl::cat(ProfGenCategory));
 
 extern cl::opt<bool> ShowDisassemblyOnly;
 extern cl::opt<bool> ShowSourceLocations;
+extern cl::opt<bool> SkipSymbolization;
 
 using namespace llvm;
 using namespace sampleprof;
 
 // Validate the command line input.
 static void validateCommandLine(StringRef BinaryPath,
                                 cl::list<std::string> &PerfTraceFilenames) {
   // Allow the invalid perfscript if we only use to show binary disassembly.
int main(int argc, const char *argv[]) {
   if (ShowDisassemblyOnly)
     return EXIT_SUCCESS;
 
   // Parse perf events and samples
   std::unique_ptr<PerfReaderBase> Reader =
       PerfReaderBase::create(Binary.get(), PerfTraceFilenames);
   Reader->parsePerfTraces(PerfTraceFilenames);
 
+  if (SkipSymbolization)
+    return EXIT_SUCCESS;
+
+  // TBD
+  if (Reader->getPerfScriptType() == PERF_LBR) {
+    WithColor::warning() << "Currently LBR only perf script is not supported!";
+    return EXIT_SUCCESS;
+  }
+
   std::unique_ptr<ProfileGenerator> Generator = ProfileGenerator::create(
       Binary.get(), Reader->getSampleCounters(), Reader->getPerfScriptType());
   Generator->generateProfile();
   Generator->write();
 
   return EXIT_SUCCESS;
 }