[llvm-gsymutil][NFC] refactor AddressRange&AddresRanges structures.

llvm-gsymutil has an implementation of AddressRange and AddressRanges
classes. That implementation might be reused in other parts

[llvm-gsymutil][NFC] refactor AddressRange&AddresRanges structures.

llvm-gsymutil has an implementation of AddressRange and AddressRanges
classes. That implementation might be reused in other parts of llvm.
This patch moves AddressRange and AddressRanges classes into llvm/ADT.

Differential Revision: https://reviews.llvm.org/D124350

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Apply clang-tidy fixes for readability-redundant-smartptr-get in DwarfTransformer.cpp (NFC)

Cleanup LLVMDWARFDebugInfo

As usual with that header cleanup series, some implicit dependencies now need to
be explicit:

llvm/DebugInfo/DWARF/DWARFContext.h no longer includes:
- "llvm/DebugInfo/DW

Cleanup LLVMDWARFDebugInfo

As usual with that header cleanup series, some implicit dependencies now need to
be explicit:

llvm/DebugInfo/DWARF/DWARFContext.h no longer includes:
- "llvm/DebugInfo/DWARF/DWARFAcceleratorTable.h"
- "llvm/DebugInfo/DWARF/DWARFCompileUnit.h"
- "llvm/DebugInfo/DWARF/DWARFDebugAbbrev.h"
- "llvm/DebugInfo/DWARF/DWARFDebugAranges.h"
- "llvm/DebugInfo/DWARF/DWARFDebugFrame.h"
- "llvm/DebugInfo/DWARF/DWARFDebugLoc.h"
- "llvm/DebugInfo/DWARF/DWARFDebugMacro.h"
- "llvm/DebugInfo/DWARF/DWARFGdbIndex.h"
- "llvm/DebugInfo/DWARF/DWARFSection.h"
- "llvm/DebugInfo/DWARF/DWARFTypeUnit.h"
- "llvm/DebugInfo/DWARF/DWARFUnitIndex.h"

Plus llvm/Support/Errc.h not included by a bunch of llvm/DebugInfo/DWARF/DWARF*.h files

Preprocessed lines to build llvm on my setup:
after: 1065629059
before: 1066621848

Which is a great diff!

Discourse thread: https://discourse.llvm.org/t/include-what-you-use-include-cleanup
Differential Revision: https://reviews.llvm.org/D119723

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[GSYM] Add Split Dwarf Support to DwarfTransformer

The convert only worked on CUs in main binary.
If it's a skeleton CU it will now use the DWO CU
when invoking handleDie.

Test Plan:
llvm-lit

Revi

[GSYM] Add Split Dwarf Support to DwarfTransformer

The convert only worked on CUs in main binary.
If it's a skeleton CU it will now use the DWO CU
when invoking handleDie.

Test Plan:
llvm-lit

Reviewed By: clayborg

Differential Revision: https://reviews.llvm.org/D118521

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Avoid by-value copies of referenced objects

These were detected by the new -Wauto-by-value-copy (D114989) warning, these by-value
constant copies need only be references.

Reviewed By: aaron.ballman

Avoid by-value copies of referenced objects

These were detected by the new -Wauto-by-value-copy (D114989) warning, these by-value
constant copies need only be references.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D114990

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Log to the right stream in DwarfTransformer::handleDie().

Since we might end up using multiple threads when logging information in the DWARFTransformer, the handleDie() method must use the supplied

Log to the right stream in DwarfTransformer::handleDie().

Since we might end up using multiple threads when logging information in the DWARFTransformer, the handleDie() method must use the supplied stream named "OS" when logging warnings and errors. When we use multiple threads, we log to a thread specific stream buffer and then use a mutex to ensure our output doesn't overlap when we emit warnings and errors after a thread is done.

Differential Revision: https://reviews.llvm.org/D109401

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Fix fallback code that gets decl file + line.

When a function has no line table, but does have debug info (DW_TAG_subprogram), we fall back to creating a line table with a single line entry that has

Fix fallback code that gets decl file + line.

When a function has no line table, but does have debug info (DW_TAG_subprogram), we fall back to creating a line table with a single line entry that has the start address of the function and the source file and line of the function declaration. The bug in this code was that we might have a DW_TAG_subprogram that uses a DW_AT_specification or DW_AT_abstract_origin that points to another DIE, and that DIE might be in another compile unit. The bug was we were grabbing the file index value from the DIE, and that index could be from the other DIE in another compile unit that has its own and compleltely different file table, so we might be using a file index from one compile unit with the file table from another. This was causing a crash in llvm-gsymuil when run against dSYM files. dsymutil, the Apple DWARF linker, will often unique types and can end up with more absolute references across different compile units.

The fix is to use the DWARFDie::getDeclFile(...) accessor as it does fetch this information correctly.

Differential Revision: https://reviews.llvm.org/D108497

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Add --quiet option to llvm-gsymutil to suppress output of warnings.

Differential Revision: https://reviews.llvm.org/D102829

[NFC] Move ValidTextRanges out of DwarfTransformer and into GsymCreator and unify address is not in GSYM errors so all strings match.

[Support] On Windows, ensure hardware_concurrency() extends to all CPU sockets and all NUMA groups

The goal of this patch is to maximize CPU utilization on multi-socket or high core count systems, s

[Support] On Windows, ensure hardware_concurrency() extends to all CPU sockets and all NUMA groups

The goal of this patch is to maximize CPU utilization on multi-socket or high core count systems, so that parallel computations such as LLD/ThinLTO can use all hardware threads in the system. Before this patch, on Windows, a maximum of 64 hardware threads could be used at most, in some cases dispatched only on one CPU socket.

== Background ==
Windows doesn't have a flat cpu_set_t like Linux. Instead, it projects hardware CPUs (or NUMA nodes) to applications through a concept of "processor groups". A "processor" is the smallest unit of execution on a CPU, that is, an hyper-thread if SMT is active; a core otherwise. There's a limit of 32-bit processors on older 32-bit versions of Windows, which later was raised to 64-processors with 64-bit versions of Windows. This limit comes from the affinity mask, which historically is represented by the sizeof(void*). Consequently, the concept of "processor groups" was introduced for dealing with systems with more than 64 hyper-threads.

By default, the Windows OS assigns only one "processor group" to each starting application, in a round-robin manner. If the application wants to use more processors, it needs to programmatically enable it, by assigning threads to other "processor groups". This also means that affinity cannot cross "processor group" boundaries; one can only specify a "preferred" group on start-up, but the application is free to allocate more groups if it wants to.

This creates a peculiar situation, where newer CPUs like the AMD EPYC 7702P (64-cores, 128-hyperthreads) are projected by the OS as two (2) "processor groups". This means that by default, an application can only use half of the cores. This situation could only get worse in the years to come, as dies with more cores will appear on the market.

== The problem ==
The heavyweight_hardware_concurrency() API was introduced so that only *one hardware thread per core* was used. Once that API returns, that original intention is lost, only the number of threads is retained. Consider a situation, on Windows, where the system has 2 CPU sockets, 18 cores each, each core having 2 hyper-threads, for a total of 72 hyper-threads. Both heavyweight_hardware_concurrency() and hardware_concurrency() currently return 36, because on Windows they are simply wrappers over std::thread::hardware_concurrency() -- which can only return processors from the current "processor group".

== The changes in this patch ==
To solve this situation, we capture (and retain) the initial intention until the point of usage, through a new ThreadPoolStrategy class. The number of threads to use is deferred as late as possible, until the moment where the std::threads are created (ThreadPool in the case of ThinLTO).

When using hardware_concurrency(), setting ThreadCount to 0 now means to use all the possible hardware CPU (SMT) threads. Providing a ThreadCount above to the maximum number of threads will have no effect, the maximum will be used instead.
The heavyweight_hardware_concurrency() is similar to hardware_concurrency(), except that only one thread per hardware *core* will be used.

When LLVM_ENABLE_THREADS is OFF, the threading APIs will always return 1, to ensure any caller loops will be exercised at least once.

Differential Revision: https://reviews.llvm.org/D71775

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Add a DWARF transformer class that converts DWARF to GSYM.

Summary:
The DWARF transformer is added as a class so it can be unit tested fully.

The DWARF is converted to GSYM format and handles many

Add a DWARF transformer class that converts DWARF to GSYM.

Summary:
The DWARF transformer is added as a class so it can be unit tested fully.

The DWARF is converted to GSYM format and handles many special cases for functions:
- omit functions in compile units with 4 byte addresses whose address is UINT32_MAX (dead stripped)
- omit functions in compile units with 8 byte addresses whose address is UINT64_MAX (dead stripped)
- omit any functions whose high PC is <= low PC (dead stripped)
- StringTable builder doesn't copy strings, so we need to make backing copies of strings but only when needed. Many strings come from sections in object files and won't need to have backing copies, but some do.
- When a function doesn't have a mangled name, store the fully qualified name by creating a string by traversing the parent decl context DIEs and then. If we don't do this, we end up having cases where some function might appear in the GSYM as "erase" instead of "std::vector<int>::erase".
- omit any functions whose address isn't in the optional TextRanges member variable of DwarfTransformer. This allows object file to register address ranges that are known valid code ranges and can help omit functions that should have been dead stripped, but just had their low PC values set to zero. In this case we have many functions that all appear at address zero and can omit these functions by making sure they fall into good address ranges on the object file. Many compilers do this when the DWARF has a DW_AT_low_pc with a DW_FORM_addr, and a DW_AT_high_pc with a DW_FORM_data4 as the offset from the low PC. In this case the linker can't write the same address to both the high and low PC since there is only a relocation for the DW_AT_low_pc, so many linkers tend to just zero it out.

Reviewers: aprantl, dblaikie, probinson

Subscribers: mgorny, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D74450

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