Summary:
This is a NFC patch moving the GNUELFDumper<ELFT>::printEnum()
function from ELFDumper into ScopedPrinter.h for reuse.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D114840
Deprecate LLVMAddAlias in favor of LLVMAddAlias2, which accepts a
value type and an address space. Previously these were extracted
from the pointer type.
Differential Revision: https://reviews.llvm.org/D114860
Ignore undefined symbols; other minor code cleanup.
Replace test objects and their asm source with a yaml equivalent.
Differential Revision: https://reviews.llvm.org/D114478
Due to the debug info merging, there may have some contexts with zero probe id, we should truncate the context to avoid misleading pre-inliner.
Reviewed By: hoy, wenlei
Differential Revision: https://reviews.llvm.org/D114284
Tools such as `llvm-objdump` or `llvm-readobj` support indirect symbol
tables. Here, support it for `obj2yaml` and `yaml2obj`.
Reviewed By: jhenderson, drodriguez
Differential Revision: https://reviews.llvm.org/D114410
In order to support generating profile with FS discriminator, three kind of changes are done in llvm-profgen:
1) Dissassemble .rodata section to check if FS discriminator var ('"__llvm_fs_discriminator__"') exists and set the corresponding flag in the binary.
2) Change the discriminator decoding in `getBaseDiscriminator` and `getDuplicationFactor`.
3) set true for `FunctionSamples::ProfileIsFS` to enable FS functionality in ProfileData.
Reviewed By: xur, hoy, wenlei
Differential Revision: https://reviews.llvm.org/D113296
This commit adds initial support to llvm-profdata to read and print
summaries of raw memprof profiles.
Summary of changes:
* Refactor shared defs to MemProfData.inc
* Extend show_main to display memprof profile summaries.
* Add a simple raw memprof profile reader.
* Add a couple of tests to tools/llvm-profdata.
Differential Revision: https://reviews.llvm.org/D114286
For nodes that are in a cycle of a profiled call graph, the current order the underlying scc_iter computes purely depends on how those nodes are reached from outside the SCC and inside the SCC, based on the Tarjan algorithm. This does not honor profile edge hotness, thus does not gurantee hot callsites to be inlined prior to cold callsites. To mitigate that, I'm adding an extra sorter on top of scc_iter to sort scc functions in the order of callsite hotness, instead of changing the internal of scc_iter.
Sorting on callsite hotness can be optimally based on detecting cycles on a directed call graph, i.e, to remove the coldest edge until a cycle is broken. However, detecting cycles isn't cheap. I'm using an MST-based approach which is faster and appear to deliver some performance wins.
Reviewed By: wenlei
Differential Revision: https://reviews.llvm.org/D114204
AutoFDO performance is sensitive to profile density, i.e., the amount of samples in the profile relative to the program size, because profiles with insufficient samples could be inaccurate due to statistical noise and thus hurt AutoFDO performance. A previous investigation showed that AutoFDO performed better on MySQL with increased amount of samples. Therefore, we implement a profile-density computation feature to give hints about profile density to users and the compiler.
We define the density of a profile Prof as follows:
- For each function A in the profile, density(A) = total_samples(A) / sizeof(A).
- density(Prof) = min(density(A)) for all functions A that are warm (defined below).
A function is considered warm if its total-samples is within top N percent of the profile. For implementation, we reuse the `ProfileSummaryBuilder::getHotCountThreshold(..)` as threshold which can be set by percent(`--profile-summary-cutoff-hot`) or by value(`--profile-summary-hot-count`).
We also introduce `--hot-function-density-threshold` to set hot function density threshold and will give suggestion if profile density is below it which implies we should increase samples.
This also applies for CS profile with all profiles merged into base.
Reviewed By: hoy, wenlei
Differential Revision: https://reviews.llvm.org/D113781
Renamed the option for llvm-cov and changed variable names to use more
inclusive terms. Also changed the binary for the test.
Reviewed By: alanphipps
Differential Revision: https://reviews.llvm.org/D112816
With link-time optimizations enabled, resulting DWARF mayend up containing
cross CU references (through the DW_AT_abstract_origin attribute).
Consider the following example:
// sum.c
__attribute__((always_inline)) int sum(int a, int b)
{
return a + b;
}
// main.c
extern int sum(int, int);
int main()
{
int a = 5, b = 10, c = sum(a, b);
return 0;
}
Compiled as follows:
$ clang -g -flto -fuse-ld=lld main.c sum.c -o main
Results in the following DWARF:
-- sum.c CU: abstract instance tree
...
0x000000b0: DW_TAG_subprogram
DW_AT_name ("sum")
DW_AT_decl_file ("sum.c")
DW_AT_decl_line (1)
DW_AT_prototyped (true)
DW_AT_type (0x000000d3 "int")
DW_AT_external (true)
DW_AT_inline (DW_INL_inlined)
0x000000bc: DW_TAG_formal_parameter
DW_AT_name ("a")
DW_AT_decl_file ("sum.c")
DW_AT_decl_line (1)
DW_AT_type (0x000000d3 "int")
0x000000c7: DW_TAG_formal_parameter
DW_AT_name ("b")
DW_AT_decl_file ("sum.c")
DW_AT_decl_line (1)
DW_AT_type (0x000000d3 "int")
...
-- main.c CU: concrete inlined instance tree
...
0x0000006d: DW_TAG_inlined_subroutine
DW_AT_abstract_origin (0x00000000000000b0 "sum")
DW_AT_low_pc (0x00000000002016ef)
DW_AT_high_pc (0x00000000002016f1)
DW_AT_call_file ("main.c")
DW_AT_call_line (5)
DW_AT_call_column (0x19)
0x00000081: DW_TAG_formal_parameter
DW_AT_location (DW_OP_reg0 RAX)
DW_AT_abstract_origin (0x00000000000000bc "a")
0x00000088: DW_TAG_formal_parameter
DW_AT_location (DW_OP_reg2 RCX)
DW_AT_abstract_origin (0x00000000000000c7 "b")
...
Note that each entry within the concrete inlined instance tree in
the main.c CU has a DW_AT_abstract_origin attribute which
refers to a corresponding entry within the abstract instance
tree in the sum.c CU.
llvm-dwarfdump --statistics did not properly report
DW_TAG_formal_parameters/DW_TAG_variables from concrete inlined
instance trees which had 0% location coverage and which
referred to a different CU, mainly because information about abstract
instance trees and their parameters/variables was stored
locally - just for the currently processed CU,
rather than globally - for all CUs.
In particular, if the concrete inlined instance tree from
the example above was to look like this
(i.e. parameter b has 0% location coverage, hence why it's missing):
0x0000006d: DW_TAG_inlined_subroutine
DW_AT_abstract_origin (0x00000000000000b0 "sum")
DW_AT_low_pc (0x00000000002016ef)
DW_AT_high_pc (0x00000000002016f1)
DW_AT_call_file ("main.c")
DW_AT_call_line (5)
DW_AT_call_column (0x19)
0x00000081: DW_TAG_formal_parameter
DW_AT_location (DW_OP_reg0 RAX)
DW_AT_abstract_origin (0x00000000000000bc "a")
llvm-dwarfdump --statistics would have not reported b as such.
Patch by Dimitrije Milosevic.
Differential revision: https://reviews.llvm.org/D113465
This patch adds parallel processing of chunks. When reducing very large
inputs, e.g. functions with 500k basic blocks, processing chunks in
parallel can significantly speed up the reduction.
To allow modifying clones of the original module in parallel, each clone
needs their own LLVMContext object. To achieve this, each job parses the
input module with their own LLVMContext. In case a job successfully
reduced the input, it serializes the result module as bitcode into a
result array.
To ensure parallel reduction produces the same results as serial
reduction, only the first successfully reduced result is used, and
results of other successful jobs are dropped. Processing resumes after
the chunk that was successfully reduced.
The number of threads to use can be configured using the -j option.
It defaults to 1, which means serial processing.
Reviewed By: Meinersbur
Differential Revision: https://reviews.llvm.org/D113857
This is another attempt at D59351 which attempted to add --update-section, but
with some heuristics for adjusting segment/section offsets/sizes in the event
the data copied into the section is larger than the original size of the section.
We are opting to not support this case. GNU's objcopy was able to do this because
the linker and objcopy are tightly coupled enough that segment reformatting was
simpler. This is not the case with llvm-objcopy and lld where they like to be separated.
This will attempt to copy data into the section without changing any other
properties of the parent segment (if the section is part of one).
Differential Revision: https://reviews.llvm.org/D112116
3d1d8c767b made
DWARFExpression::iterator's Operation member `mutable`. After a few prep
commits, the iterator can instead be made a `const` iterator since no
caller can change the Operation.
Differential Revision: https://reviews.llvm.org/D113958
This patch moves the logic to clone and check a new chunk into a new
function, to allow re-use in a follow-up patch that implements parallel
reductions.
Reviewed By: dblaikie
Differential Revision: https://reviews.llvm.org/D113856
Textual LLVM IR files are much bigger and take longer to write to disk.
To avoid the extra cost incurred by serializing to text, this patch adds
an option to save temporary files as bitcode instead.
Reviewed By: aeubanks
Differential Revision: https://reviews.llvm.org/D113858
Adding `-use-loadable-segment-as-base` to allow use of first loadable segment for calculating offset. By default first executable segment is used for calculating offset. The switch helps compatibility with unsymbolized profile generated from older tools.
Differential Revision: https://reviews.llvm.org/D113727
The existing logic adds `-rpath` to CGO_LDFLAGS, which is not a valid linker option on AIX. This patch substitutes it with `-blibpath` on AIX.
Reviewed By: daltenty
Differential Revision: https://reviews.llvm.org/D113704
Commit 69be352a19 restricted the MachO debugger support testcase to run on
Darwin only, but we still need to disable debugger support by default for
other noexec tests.
This patch introduces a -debugger-support option to llvm-jitlink that is
on-by-default when executing code, and off-by-default for noexec tests. This
should prevent regression tests from trying (and failing) to set up MachO
debugging support when running on non-Darwin platforms.
to explicitly enable/disable support.
This reapplies e1933a0488 (which was reverted in
f55ba3525e due to bot failures, e.g.
https://lab.llvm.org/buildbot/#/builders/117/builds/2768).
The bot failures were due to a missing symbol error: We use the input object's
mangling to decide how to mangle the debug-info registration function name. This
caused lookup of the registration function to fail when the input object
mangling didn't match the host mangling.
Disbaling the test on non-Darwin platforms is the easiest short-term solution.
I have filed https://llvm.org/PR52503 with a proposed longer term solution.
This commit adds a new plugin, GDBJITDebugInfoRegistrationPlugin, that checks
for objects containing debug info and registers any debug info found via the
GDB JIT registration API.
To enable this registration without redundantly representing non-debug sections
this plugin synthesizes a new embedded object within a section of the LinkGraph.
An allocation action is used to make the registration call.
Currently MachO only. ELF users can still use the DebugObjectManagerPlugin. The
two are likely to be merged in the near future.
VarStreamArrayIterator returns a reference to a just-computed internal
value. Change it to iterate over `const ValueType` to avoid allowing
clients to mutate the internal state, and to drop the
non-`const`-qualified operator*().
The removed operator*() was from 175d70ee5c to get
iterator_facade_base::operator->() working, and this fixes the root
cause instead: setting `T` to `const ValueType` causes
iterator_facade_base to infer `PointerT` as `const ValueType*`.
Ironically, this is the last blocker for removing the const-incorrect
overload of `iterator_facade_base::operator->()`, whose presence
triggered adding the workaround in the first place :).
Differential Revision: https://reviews.llvm.org/D113797
Previously we set `isFuncEntry` flag to true when the funcName from DWARF is equal to the name in symbol table and we use this flag to ignore reporting callsite sample that's from an intra func branch. However, in HHVM, it appears that the symbol table name is inconsistent with the dwarf info func name, it's likely due to `OptimizeGlobalAliases`.
This change is a workaround in llvm-profgen side to mark the only one range as the function entry and add warnings for the remaining inconsistence.
This also fixed a missing `getCanonicalFnName` for symbol name which caused the mismatching as well.
Reviewed By: hoy, wenlei
Differential Revision: https://reviews.llvm.org/D113492
The check was failing because it was matching against the end of the range, not
the start.
This bug wasn't causing the ORC-RT MachO TLV regression test to fail because
we were only logging deallocation errors (including TLV deregistration errors)
and not actually returning a failure code. This commit updates llvm-jitlink to
report the errors properly.
Add support for demangling Rust v0 symbols to llvm-nm by reusing
nonMicrosoftDemangle which supports both Itanium and Rust mangling.
Reviewed By: dblaikie, jhenderson
Differential Revision: https://reviews.llvm.org/D111937
Having a separate counting method runs the risk of a mismatch between
the actual reduction method and the counting method.
Instead, create an Oracle that always returns true for shouldKeep(), run
the reduction, and count how many times shouldKeep() was called. The
module should not be modified if shouldKeep() always returns true.
Reviewed By: Meinersbur
Differential Revision: https://reviews.llvm.org/D113537
Metadata operands tend to require special conditions, especially on dbg
intrinsics. We also don't have a zero value for metadata.
Replacing callee operands is a little weird, since calling undef/null
doesn't make sense. It also causes tons of invalid reductions when
reducing calls to intrinsics since only arguments to intrinsics can be
of the metadata type.
Reviewed By: Meinersbur
Differential Revision: https://reviews.llvm.org/D113532
Add a new "operands-skip" pass whose goal is to remove instructions in the middle of dependency chains. For instance:
```
%baseptr = alloca i32
%arrayidx = getelementptr i32, i32* %baseptr, i32 %idxprom
store i32 42, i32* %arrayidx
```
might be reducible to
```
%baseptr = alloca i32
%arrayidx = getelementptr ... ; now dead, together with the computation of %idxprom
store i32 42, i32* %baseptr
```
Other passes would either replace `%baseptr` with undef (operands, instructions) or move it to become a function argument (operands-to-args), both of which might fail the interestingness check.
In principle the implementation allows operand replacement with any value or instruction in the function that passes the filter constraints (same type, dominance, "more reduced"), but is limited in this patch to values that are directly or indirectly used to compute the current operand value, motivated by the example above. Additionally, function arguments are added to the candidate set which helps reducing the number of relevant arguments mitigating a concern of too many arguments mentioned in https://reviews.llvm.org/D110274#3025013.
Possible future extensions:
* Instead of requiring the same type, bitcast/trunc/zext could be automatically inserted for some more flexibility.
* If undef is added to the candidate set, "operands-skip"is able to produce any reduction that "operands" can do. Additional candidates might be zero and one, where the "reductive power" classification can prefer one over the other. If undefined behaviour should not be introduced, undef can be removed from the candidate set.
Recommit after resolving conflict with D112651 and reusing
shouldReduceOperand from D113532.
Reviewed By: aeubanks
Differential Revision: https://reviews.llvm.org/D111818
Add a new "operands-skip" pass whose goal is to remove instructions in the middle of dependency chains. For instance:
```
%baseptr = alloca i32
%arrayidx = getelementptr i32, i32* %baseptr, i32 %idxprom
store i32 42, i32* %arrayidx
```
might be reducible to
```
%baseptr = alloca i32
%arrayidx = getelementptr ... ; now dead, together with the computation of %idxprom
store i32 42, i32* %baseptr
```
Other passes would either replace `%baseptr` with undef (operands, instructions) or move it to become a function argument (operands-to-args), both of which might fail the interestingness check.
In principle the implementation allows operand replacement with any value or instruction in the function that passes the filter constraints (same type, dominance, "more reduced"), but is limited in this patch to values that are directly or indirectly used to compute the current operand value, motivated by the example above. Additionally, function arguments are added to the candidate set which helps reducing the number of relevant arguments mitigating a concern of too many arguments mentioned in https://reviews.llvm.org/D110274#3025013.
Possible future extensions:
* Instead of requiring the same type, bitcast/trunc/zext could be automatically inserted for some more flexibility.
* If undef is added to the candidate set, "operands-skip"is able to produce any reduction that "operands" can do. Additional candidates might be zero and one, where the "reductive power" classification can prefer one over the other. If undefined behaviour should not be introduced, undef can be removed from the candidate set.
Reviewed By: aeubanks
Differential Revision: https://reviews.llvm.org/D111818
When reducing functions with very large basic blocks (~ almost 1 million
BBs), the majority of time is spent maintaining the order in the std::set
for the basic blocks to keep.
In those cases, DenseSet<> is much more efficient. Use it instead.
This patch adds a fuzzing helper tool for D demangler by feeding the demangler API with
pseudo-random null terminated strings with the help of libfuzzer heuristics.
Reviewed By: dblaikie
Differential Revision: https://reviews.llvm.org/D111432
Previously, if the basic-blocks delta pass tried to remove a basic block
that was the last basic block in a function that did not have external
or weak linkage, the resulting IR would become invalid. Since removing
the last basic block in a function is effectively identical to removing
the function body itself, we check explicitly for this case and if we
detect it, we run the same logic as in ReduceFunctionBodies.cpp
Reviewed By: aeubanks
Differential Revision: https://reviews.llvm.org/D113486
Sometimes if llvm-reduce is interrupted in the middle of a delta pass on
a large file, it can take quite some time for the tool to start actually
doing new work if it is restarted again on the partially-reduced file. A
lot of time ends up being spent testing large chunks when these large
chunks are very unlikely to actually pass the interestingness test. In
cases like this, the tool will complete faster if the starting
granularity is reduced to a finer amount. Thus, we introduce a command
line flag that automatically divides the chunks into smaller subsets a
fixed, user-specified number of times prior to beginning the core loop.
Reviewed By: aeubanks
Differential Revision: https://reviews.llvm.org/D112651
Esme-Yi