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Merged
merged 1 commit into from
Aug 4, 2022
Merged

Fix typo in README.md #1

merged 1 commit into from
Aug 4, 2022

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@smeenai smeenai commented Aug 4, 2022

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@lanza lanza merged commit 31a1c5d into llvm:main Aug 4, 2022
lanza pushed a commit that referenced this pull request Sep 22, 2022
I encountered an issue where `p &variable` was finding an incorrect address for
32-bit PIC ELF files loaded into a running process.  The problem was that the
R_386_32 ELF relocations were not being applied to the DWARF section, so all
variables in that file were reporting as being at the start of their respective
section.  There is an assert that catches this on debug builds, but silently
ignores the issue on non-debug builds.

In this changeset, I added handling for the R_386_32 relocation type to
ObjectFileELF, and a supporting function to ELFRelocation to differentiate
between DT_REL & DT_RELA in ObjectFileELF::ApplyRelocations().

Demonstration of issue:
```
[dmlary@host work]$ cat rel.c
volatile char padding[32] = "make sure var isnt at .data+0";
volatile char var[] = "test";
[dmlary@host work]$ gcc -c rel.c -FPIC -fpic -g -m32

[dmlary@host work]$ lldb ./exec
(lldb) target create "./exec"
Current executable set to '/home/dmlary/src/work/exec' (i386).
(lldb) process launch --stop-at-entry
Process 21278 stopped
* thread #1, name = 'exec', stop reason = signal SIGSTOP
    frame #0: 0xf7fdb150 ld-2.17.so`_start
ld-2.17.so`_start:
->  0xf7fdb150 <+0>: movl   %esp, %eax
    0xf7fdb152 <+2>: calll  0xf7fdb990                ; _dl_start

ld-2.17.so`_dl_start_user:
    0xf7fdb157 <+0>: movl   %eax, %edi
    0xf7fdb159 <+2>: calll  0xf7fdb140
Process 21278 launched: '/home/dmlary/src/work/exec' (i386)

(lldb) image add ./rel.o
(lldb) image load --file rel.o .text 0x40000000 .data 0x50000000
section '.text' loaded at 0x40000000
section '.data' loaded at 0x50000000

(lldb) image dump symtab rel.o
Symtab, file = rel.o, num_symbols = 13:
               Debug symbol
               |Synthetic symbol
               ||Externally Visible
               |||
Index   UserID DSX Type            File Address/Value Load Address       Size               Flags      Name
------- ------ --- --------------- ------------------ ------------------ ------------------ ---------- ----------------------------------
[    0]      1     SourceFile      0x0000000000000000                    0x0000000000000000 0x00000004 rel.c
[    1]      2     Invalid         0x0000000000000000                    0x0000000000000020 0x00000003
[    2]      3     Invalid         0x0000000000000000 0x50000000 0x0000000000000020 0x00000003
[    3]      4     Invalid         0x0000000000000025                    0x0000000000000000 0x00000003
[    4]      5     Invalid         0x0000000000000000                    0x0000000000000020 0x00000003
[    5]      6     Invalid         0x0000000000000000                    0x0000000000000020 0x00000003
[    6]      7     Invalid         0x0000000000000000                    0x0000000000000020 0x00000003
[    7]      8     Invalid         0x0000000000000000                    0x0000000000000020 0x00000003
[    8]      9     Invalid         0x0000000000000000                    0x0000000000000020 0x00000003
[    9]     10     Invalid         0x0000000000000000                    0x0000000000000020 0x00000003
[   10]     11     Invalid         0x0000000000000000                    0x0000000000000020 0x00000003
[   11]     12   X Data            0x0000000000000000 0x50000000 0x0000000000000020 0x00000011 padding
[   12]     13   X Data            0x0000000000000020 0x50000020 0x0000000000000005 0x00000011 var

(lldb) p &var
(volatile char (*)[5]) $1 = 0x50000000
```

Reviewed By: labath

Differential Revision: https://reviews.llvm.org/D132954
lanza pushed a commit that referenced this pull request Oct 10, 2022
…with auto return types

**Summary**

The primary motivation for this patch is to make sure we handle
the step-in behaviour for functions in the `std` namespace which
have an `auto` return type. Currently the default `step-avoid-regex`
setting is `^std::` but LLDB will still step into template functions
with `auto` return types in the `std` namespace.

**Details**
When we hit a breakpoint and check whether we should stop, we call
into `ThreadPlanStepInRange::FrameMatchesAvoidCriteria`. We then ask
for the frame function name via `SymbolContext::GetFunctionName(Mangled::ePreferDemangledWithoutArguments)`.
This ends up trying to parse the function name using `CPlusPlusLanguage::MethodName::GetBasename` which
parses the raw demangled name string.

`CPlusPlusNameParser::ParseFunctionImpl` calls `ConsumeTypename` to skip
the (in our case auto) return type of the demangled name (according to the
Itanium ABI this is a valid thing to encode into the mangled name). However,
`ConsumeTypename` doesn't strip out a plain `auto` identifier
(it will strip a `decltype(auto) return type though). So we are now left with
a basename that still has the return type in it, thus failing to match the `^std::`
regex.

Example frame where the return type is still part of the function name:
```
Process 1234 stopped
* thread #1, stop reason = step in
    frame #0: 0x12345678 repro`auto std::test_return_auto<int>() at main.cpp:12:5
   9
   10   template <class>
   11   auto test_return_auto() {
-> 12       return 42;
   13   }
```

This is another case where the `CPlusPlusNameParser` breaks us in subtle ways
due to evolving C++ syntax. There are longer-term plans of replacing the hand-rolled
C++ parser with an alternative that uses the mangle tree API to do the parsing for us.

**Testing**

* Added API and unit-tests
* Adding support for ABI tags into the parser is a larger undertaking
  which we would rather solve properly by using libcxxabi's mangle tree
  parser

Differential Revision: https://reviews.llvm.org/D135413
lanza pushed a commit that referenced this pull request Dec 17, 2022
…ction selection.

Before this patch:
- For `r = or op0, op1`, `tryBitfieldInsertOpFromOr` combines it to BFI when
  1) one of the two operands is bit-field-positioning or bit-field-extraction op; and
  2) bits from the two operands don't overlap

After this patch:
- Right before OR is combined to BFI, evaluates if ORR with left-shifted operand is better.

A motivating example (https://godbolt.org/z/rnMrzs5vn, which is added as a test case in `test_orr_not_bfi` in `CodeGen/AArch64/bitfield-insert.ll`)

For IR:
```
define i64 @test_orr_not_bfxil(i64 %0) {
  %2 = and i64 %0, 127
  %3 = lshr i64 %0, 1
  %4 = and i64 %3, 16256
  %5 = or i64 %4, %2
  ret i64 %5
}
```

Before:
```
   lsr     x8, x0, #1
   and     x8, x8, #0x3f80
   bfxil   x8, x0, #0, #7
```

After:
```
   ubfx x8, x0, #8, #7
   and x9, x0, #0x7f
   orr x0, x9, x8, lsl #7
```

Reviewed By: dmgreen

Differential Revision: https://reviews.llvm.org/D135102
lanza pushed a commit that referenced this pull request Dec 17, 2022
AArch64InstrInfo::optimizePTestInstr attempts to remove a PTEST of a
predicate generating operation that identically sets flags (implictly).

When the PTEST and the predicate-generating operation use the same mask
the PTEST is currently removed. This is incorrect since it doesn't
consider element size. PTEST operates on 8-bit predicates, but for
instructions like compare that also support 16/32/64-bit predicates, the
implicit PTEST performed by the instruction will consider fewer lanes
for these element sizes and could set different first or last active
flags.

For example, consider the following instruction sequence

  ptrue p0.b			; P0=1111-1111-1111-1111
  index z0.s, #0, #1		; Z0=<0,1,2,3>
  index z1.s, #1, #1		; Z1=<1,2,3,4>
  cmphi p1.s, p0/z, z1.s, z0.s  ; P1=0001-0001-0001-0001
				;       ^ last active
  ptest p0, p1.b		; P1=0001-0001-0001-0001
				;     ^ last active

where the compare generates a canonical all active 32-bit predicate (equivalent
to 'ptrue p1.s, all'). The implicit PTEST sets the last active flag, whereas
the PTEST instruction with the same mask doesn't.

This patch restricts the optimization to instructions operating on 8-bit
predicates. One caveat is the optimization is safe regardless of element
size for any active, this will be addressed in a later patch.

Reviewed By: bsmith

Differential Revision: https://reviews.llvm.org/D137716
lanza pushed a commit that referenced this pull request Dec 17, 2022
Verify three cases of G_UNMERGE_VALUES separately:

1. Splitting a vector into subvectors (the converse of
   G_CONCAT_VECTORS).
2. Splitting a vector into its elements (the converse of
   G_BUILD_VECTOR).
3. Splitting a scalar into smaller scalars (the converse of
   G_MERGE_VALUES).

Previously #1 allowed strange combinations like this:
  %1:_(<2 x s16>),%2:_(<2 x s16>) = G_UNMERGE_VALUES %0(<2 x s32>)
This has been tightened up to check that the source and destination
element types match, and some MIR test cases updated accordingly.

Differential Revision: https://reviews.llvm.org/D111132
lanza pushed a commit that referenced this pull request Dec 17, 2022
The Assignment Tracking debug-info feature is outlined in this RFC:

https://discourse.llvm.org/t/
rfc-assignment-tracking-a-better-way-of-specifying-variable-locations-in-ir

Add initial revision of assignment tracking analysis pass
---------------------------------------------------------
This patch squashes five individually reviewed patches into one:

    #1 https://reviews.llvm.org/D136320
    #2 https://reviews.llvm.org/D136321
    #3 https://reviews.llvm.org/D136325
    #4 https://reviews.llvm.org/D136331
    #5 https://reviews.llvm.org/D136335

Patch #1 introduces 2 new files: AssignmentTrackingAnalysis.h and .cpp. The
two subsequent patches modify those files only. Patch #4 plumbs the analysis
into SelectionDAG, and patch #5 is a collection of tests for the analysis as
a whole.

The analysis was broken up into smaller chunks for review purposes but for the
most part the tests were written using the whole analysis. It would be possible
to break up the tests for patches #1 through #3 for the purpose of landing the
patches seperately. However, most them would require an update for each
patch. In addition, patch #4 - which connects the analysis to SelectionDAG - is
required by all of the tests.

If there is build-bot trouble, we might try a different landing sequence.

Analysis problem and goal
-------------------------

Variables values can be stored in memory, or available as SSA values, or both.
Using the Assignment Tracking metadata, it's not possible to determine a
variable location just by looking at a debug intrinsic in
isolation. Instructions without any metadata can change the location of a
variable. The meaning of dbg.assign intrinsics changes depending on whether
there are linked instructions, and where they are relative to those
instructions. So we need to analyse the IR and convert the embedded information
into a form that SelectionDAG can consume to produce debug variable locations
in MIR.

The solution is a dataflow analysis which, aiming to maximise the memory
location coverage for variables, outputs a mapping of instruction positions to
variable location definitions.

API usage
---------

The analysis is named `AssignmentTrackingAnalysis`. It is added as a required
pass for SelectionDAGISel when assignment tracking is enabled.

The results of the analysis are exposed via `getResults` using the returned
`const FunctionVarLocs *`'s const methods:

    const VarLocInfo *single_locs_begin() const;
    const VarLocInfo *single_locs_end() const;
    const VarLocInfo *locs_begin(const Instruction *Before) const;
    const VarLocInfo *locs_end(const Instruction *Before) const;
    void print(raw_ostream &OS, const Function &Fn) const;

Debug intrinsics can be ignored after running the analysis. Instead, variable
location definitions that occur between an instruction `Inst` and its
predecessor (or block start) can be found by looping over the range:

    locs_begin(Inst), locs_end(Inst)

Similarly, variables with a memory location that is valid for their lifetime
can be iterated over using the range:

    single_locs_begin(), single_locs_end()

Further detail
--------------

For an explanation of the dataflow implementation and the integration with
SelectionDAG, please see the reviews linked at the top of this commit message.

Reviewed By: jmorse
lanza pushed a commit that referenced this pull request May 3, 2023
Change https://reviews.llvm.org/D140059 exposed the following crash in
Z3Solver, where bit widths were not checked consistently with that
change. This change makes the check consistent, and fixes the crash.

```
clang: <root>/llvm/include/llvm/ADT/APSInt.h:99:
  int64_t llvm::APSInt::getExtValue() const: Assertion
  `isRepresentableByInt64() && "Too many bits for int64_t"' failed.
...
Stack dump:
0. Program arguments: clang -cc1 -internal-isystem <root>/lib/clang/16/include
  -nostdsysteminc -analyze -analyzer-checker=core,unix.Malloc,debug.ExprInspection
  -analyzer-config crosscheck-with-z3=true -verify reproducer.c

 #0 0x00000000045b3476 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int)
  <root>/llvm/lib/Support/Unix/Signals.inc:567:22
 #1 0x00000000045b3862 PrintStackTraceSignalHandler(void*)
  <root>/llvm/lib/Support/Unix/Signals.inc:641:1
 #2 0x00000000045b14a5 llvm::sys::RunSignalHandlers()
  <root>/llvm/lib/Support/Signals.cpp:104:20
 #3 0x00000000045b2eb4 SignalHandler(int)
  <root>/llvm/lib/Support/Unix/Signals.inc:412:1
 ...
 #9 0x0000000004be2eb3 llvm::APSInt::getExtValue() const
  <root>/llvm/include/llvm/ADT/APSInt.h:99:5
  <root>/llvm/lib/Support/Z3Solver.cpp:740:53
  clang::ASTContext&, clang::ento::SymExpr const*, llvm::APSInt const&, llvm::APSInt const&, bool)
  <root>/clang/include/clang/StaticAnalyzer/Core/PathSensitive/SMTConv.h:552:61
```

Reviewed By: steakhal

Differential Revision: https://reviews.llvm.org/D142627
lanza pushed a commit that referenced this pull request May 3, 2023
…ak ordering

`std::sort` requires a comparison operator that obides by strict weak
ordering. `operator<=` on pointer does not and leads to undefined
behaviour. Specifically, when we grow the `scratch_type_systems` vector
slightly larger (and thus take `std::sort` down a slightly different
codepath), we segfault. This happened while working on a patch that
would in fact grow this vector. In such a case ASAN reports:

```
$ ./bin/lldb ./lldb-test-build.noindex/lang/cpp/complete-type-check/TestCppIsTypeComplete.test_builtin_types/a.out -o "script -- lldb.target.FindFirstType(\"void\")"
(lldb) script -- lldb.target.FindFirstType("void")
=================================================================
==59975==ERROR: AddressSanitizer: container-overflow on address 0x000108f6b510 at pc 0x000280177b4c bp 0x00016b7d7430 sp 0x00016b7d7428
READ of size 8 at 0x000108f6b510 thread T0
    #0 0x280177b48 in std::__1::shared_ptr<lldb_private::TypeSystem>::shared_ptr[abi:v15006](std::__1::shared_ptr<lldb_private::TypeSystem> const&)+0xb4 (/Users/michaelbuch/Git/lldb-build-main-no-modules/lib/liblldb.17.0.0git.dylib:arm64+0x177b48)
(BuildId: ea963d2c0d47354fb647f5c5f32b76d932000000200000000100000000000d00)
    #1 0x280dcc008 in void std::__1::__introsort<std::__1::_ClassicAlgPolicy, lldb_private::Target::GetScratchTypeSystems(bool)::$_3&, std::__1::shared_ptr<lldb_private::TypeSystem>*>(std::__1::shared_ptr<lldb_private::TypeSystem>*, std::__1::shared_
ptr<lldb_private::TypeSystem>*, lldb_private::Target::GetScratchTypeSystems(bool)::$_3&, std::__1::iterator_traits<std::__1::shared_ptr<lldb_private::TypeSystem>*>::difference_type)+0x1050 (/Users/michaelbuch/Git/lldb-build-main-no-modules/lib/liblld
b.17.0.0git.dylib:arm64+0xdcc008) (BuildId: ea963d2c0d47354fb647f5c5f32b76d932000000200000000100000000000d00)
    #2 0x280d88788 in lldb_private::Target::GetScratchTypeSystems(bool)+0x5a4 (/Users/michaelbuch/Git/lldb-build-main-no-modules/lib/liblldb.17.0.0git.dylib:arm64+0xd88788) (BuildId: ea963d2c0d47354fb647f5c5f32b76d932000000200000000100000000000d00)
    #3 0x28021f0b4 in lldb::SBTarget::FindFirstType(char const*)+0x624 (/Users/michaelbuch/Git/lldb-build-main-no-modules/lib/liblldb.17.0.0git.dylib:arm64+0x21f0b4) (BuildId: ea963d2c0d47354fb647f5c5f32b76d932000000200000000100000000000d00)
    #4 0x2804e9590 in _wrap_SBTarget_FindFirstType(_object*, _object*)+0x26c (/Users/michaelbuch/Git/lldb-build-main-no-modules/lib/liblldb.17.0.0git.dylib:arm64+0x4e9590) (BuildId: ea963d2c0d47354fb647f5c5f32b76d932000000200000000100000000000d00)
    #5 0x1062d3ad4 in cfunction_call+0x5c (/opt/homebrew/Cellar/[email protected]/3.11.1/Frameworks/Python.framework/Versions/3.11/Python:arm64+0xcfad4) (BuildId: c9efc4bbb1943f9a9b7cc4e91fce477732000000200000000100000000000d00)

<--- snipped --->

0x000108f6b510 is located 400 bytes inside of 512-byte region [0x000108f6b380,0x000108f6b580)
allocated by thread T0 here:
    #0 0x105209414 in wrap__Znwm+0x74 (/Applications/Xcode2.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/clang/14.0.3/lib/darwin/libclang_rt.asan_osx_dynamic.dylib:arm64e+0x51414) (BuildId: 0a44828ceb64337bbfff60b22cd838f0320000
00200000000100000000000b00)
    #1 0x280dca3b4 in std::__1::__split_buffer<std::__1::shared_ptr<lldb_private::TypeSystem>, std::__1::allocator<std::__1::shared_ptr<lldb_private::TypeSystem>>&>::__split_buffer(unsigned long, unsigned long, std::__1::allocator<std::__1::shared_pt
r<lldb_private::TypeSystem>>&)+0x11c (/Users/michaelbuch/Git/lldb-build-main-no-modules/lib/liblldb.17.0.0git.dylib:arm64+0xdca3b4) (BuildId: ea963d2c0d47354fb647f5c5f32b76d932000000200000000100000000000d00)
    #2 0x280dc978c in void std::__1::vector<std::__1::shared_ptr<lldb_private::TypeSystem>, std::__1::allocator<std::__1::shared_ptr<lldb_private::TypeSystem>>>::__push_back_slow_path<std::__1::shared_ptr<lldb_private::TypeSystem> const&>(std::__1::s
hared_ptr<lldb_private::TypeSystem> const&)+0x13c (/Users/michaelbuch/Git/lldb-build-main-no-modules/lib/liblldb.17.0.0git.dylib:arm64+0xdc978c) (BuildId: ea963d2c0d47354fb647f5c5f32b76d932000000200000000100000000000d00)
    #3 0x280d88dec in std::__1::vector<std::__1::shared_ptr<lldb_private::TypeSystem>, std::__1::allocator<std::__1::shared_ptr<lldb_private::TypeSystem>>>::push_back[abi:v15006](std::__1::shared_ptr<lldb_private::TypeSystem> const&)+0x80 (/Users/mic
haelbuch/Git/lldb-build-main-no-modules/lib/liblldb.17.0.0git.dylib:arm64+0xd88dec) (BuildId: ea963d2c0d47354fb647f5c5f32b76d932000000200000000100000000000d00)
    #4 0x280d8857c in lldb_private::Target::GetScratchTypeSystems(bool)+0x398 (/Users/michaelbuch/Git/lldb-build-main-no-modules/lib/liblldb.17.0.0git.dylib:arm64+0xd8857c) (BuildId: ea963d2c0d47354fb647f5c5f32b76d932000000200000000100000000000d00)
    #5 0x28021f0b4 in lldb::SBTarget::FindFirstType(char const*)+0x624 (/Users/michaelbuch/Git/lldb-build-main-no-modules/lib/liblldb.17.0.0git.dylib:arm64+0x21f0b4) (BuildId: ea963d2c0d47354fb647f5c5f32b76d932000000200000000100000000000d00)
    #6 0x2804e9590 in _wrap_SBTarget_FindFirstType(_object*, _object*)+0x26c (/Users/michaelbuch/Git/lldb-build-main-no-modules/lib/liblldb.17.0.0git.dylib:arm64+0x4e9590) (BuildId: ea963d2c0d47354fb647f5c5f32b76d932000000200000000100000000000d00)
    #7 0x1062d3ad4 in cfunction_call+0x5c (/opt/homebrew/Cellar/[email protected]/3.11.1/Frameworks/Python.framework/Versions/3.11/Python:arm64+0xcfad4) (BuildId: c9efc4bbb1943f9a9b7cc4e91fce477732000000200000000100000000000d00)
    #8 0x10627fff0 in _PyObject_MakeTpCall+0x7c (/opt/homebrew/Cellar/[email protected]/3.11.1/Frameworks/Python.framework/Versions/3.11/Python:arm64+0x7bff0) (BuildId: c9efc4bbb1943f9a9b7cc4e91fce477732000000200000000100000000000d00)
    #9 0x106378a98 in _PyEval_EvalFrameDefault+0xbcf8 (/opt/homebrew/Cellar/[email protected]/3.11.1/Frameworks/Python.framework/Versions/3.11/Python:arm64+0x174a98) (BuildId: c9efc4bbb1943f9a9b7cc4e91fce477732000000200000000100000000000d00)
```

Differential Revision: https://reviews.llvm.org/D142709
lanza pushed a commit that referenced this pull request May 3, 2023
… -analyzer-config

I am working on another patch that changes StringMap's hash function,
which changes the iteration order here, and breaks some tests,
specifically:

    clang/test/Analysis/NSString.m
    clang/test/Analysis/shallow-mode.m

with errors like:

    generated arguments do not match in round-trip
    generated arguments #1 in round-trip: <...> "-analyzer-config" "ipa=inlining" "-analyzer-config" "max-nodes=75000" <...>
    generated arguments #2 in round-trip: <...> "-analyzer-config" "max-nodes=75000" "-analyzer-config" "ipa=inlining" <...>

To avoid this, sort the options by key, instead of using the default map
iteration order.

Reviewed By: jansvoboda11, MaskRay

Differential Revision: https://reviews.llvm.org/D142861
lanza pushed a commit that referenced this pull request May 3, 2023
This reverts commit d768b97.

Causes sanitizer failure: https://lab.llvm.org/buildbot/#/builders/238/builds/1114

```
/b/sanitizer-aarch64-linux-bootstrap-ubsan/build/llvm-project/llvm/lib/Support/xxhash.cpp:107:12: runtime error: applying non-zero offset 8 to null pointer
    #0 0xaaaab28ec6c8 in llvm::xxHash64(llvm::StringRef) /b/sanitizer-aarch64-linux-bootstrap-ubsan/build/llvm-project/llvm/lib/Support/xxhash.cpp:107:12
    #1 0xaaaab28cbd38 in llvm::StringMapImpl::LookupBucketFor(llvm::StringRef) /b/sanitizer-aarch64-linux-bootstrap-ubsan/build/llvm-project/llvm/lib/Support/StringMap.cpp:87:28
```

Probably causes test failure in `warn-unsafe-buffer-usage-fixits-local-var-span.cpp`: https://lab.llvm.org/buildbot/#/builders/60/builds/10619

Probably causes reverse-iteration test failure in `test-output-format.ll`: https://lab.llvm.org/buildbot/#/builders/54/builds/3545
lanza pushed a commit that referenced this pull request May 3, 2023
For example, if you have a chain of inlined funtions like this:

   1 #include <stdlib.h>
   2 int g1 = 4, g2 = 6;
   3
   4 static inline void bar(int q) {
   5   if (q > 5)
   6     abort();
   7 }
   8
   9 static inline void foo(int q) {
  10   bar(q);
  11 }
  12
  13 int main() {
  14   foo(g1);
  15   foo(g2);
  16   return 0;
  17 }

with optimizations you could end up with a single abort call for the two
inlined instances of foo(). When merging the locations for those inlined
instances you would previously end up with a 0:0 location in main().
Leaving out that inlined chain from the location for the abort call
could make troubleshooting difficult in some cases.

This patch changes DILocation::getMergedLocation() to try to handle such
cases. The function is rewritten to first find a common starting point
for the two locations (same subprogram and inlined-at location), and
then in reverse traverses the inlined-at chain looking for matches in
each subprogram. For each subprogram, the merge function will find the
nearest common scope for the two locations, and matching line and
column (or set them to 0 if not matching).

In the example above, you will for the abort call get a location in
bar() at 6:5, inlined in foo() at 10:3, inlined in main() at 0:0 (since
the two inlined functions are on different lines, but in the same
scope).

I have not seen anything in the DWARF standard that would disallow
inlining a non-zero location at 0:0 in the inlined-at function, and both
LLDB and GDB seem to accept these locations (with D142552 needed for
LLDB to handle cases where the file, line and column number are all 0).
One incompatibility with GDB is that it seems to ignore 0-line locations
in some cases, but I am not aware of any specific issue that this patch
produces related to that.

With x86-64 LLDB (trunk) you previously got:

  frame #0: 0x00007ffff7a44930 libc.so.6`abort
  frame #1: 0x00005555555546ec a.out`main at merge.c:0

and will now get:

  frame #0: 0x[...] libc.so.6`abort
  frame #1: 0x[...] a.out`main [inlined] bar(q=<unavailable>) at merge.c:6:5
  frame #2: 0x[...] a.out`main [inlined] foo(q=<unavailable>) at merge.c:10:3
  frame #3: 0x[...] a.out`main at merge.c:0

and with x86-64 GDB (11.1) you will get:

  (gdb) bt
  #0  0x00007ffff7a44930 in abort () from /lib64/libc.so.6
  #1  0x00005555555546ec in bar (q=<optimized out>) at merge.c:6
  #2  foo (q=<optimized out>) at merge.c:10
  #3  0x00005555555546ec in main ()

Reviewed By: aprantl, dblaikie

Differential Revision: https://reviews.llvm.org/D142556
lanza pushed a commit that referenced this pull request May 3, 2023
Previously we only looked at the si_signo field, so you got:
```
(lldb) bt
* thread #1, name = 'a.out.mte', stop reason = signal SIGSEGV
  * frame #0: 0x00000000004007f4
```
This patch adds si_code so we can show:
```
(lldb) bt
* thread #1, name = 'a.out.mte', stop reason = signal SIGSEGV: sync tag check fault
  * frame #0: 0x00000000004007f4
```

The order of errno and code was incorrect in ElfLinuxSigInfo::Parse.
It was the order that a "swapped" siginfo arch would use, which for Linux,
is only MIPS. We removed MIPS Linux support some time ago.

See:
https://github.com/torvalds/linux/blob/fe15c26ee26efa11741a7b632e9f23b01aca4cc6/include/uapi/asm-generic/siginfo.h#L121

A test is added using memory tagging faults. Which were the original
motivation for the changes.

Reviewed By: JDevlieghere

Differential Revision: https://reviews.llvm.org/D146045
lanza pushed a commit that referenced this pull request May 3, 2023
This change prevents rare deadlocks observed for specific macOS/iOS GUI
applications which issue many `dlopen()` calls from multiple different
threads at startup and where TSan finds and reports a race during
startup.  Providing a reliable test for this has been deemed infeasible.

Although I've only observed this deadlock on Apple platforms,
conceptually the cause is not confined to Apple code so the fix lives in
platform-independent code.

Deadlock scenario:
```
Thread 2                    | Thread 4
ReportRace()                |
Lock internal TSan mutexes  |
  &ctx->slot_mtx            |
                            | dlopen() interceptor
                            | OnLibraryLoaded()
                            | MemoryMappingLayout::DumpListOfModules()
                            | calls dyld API, which takes internal lock
                            | lock() interceptor
                            | TSan tries to take internal mutexes again
                            |   &ctx->slot_mtx
call into symbolizer        |
MemoryMappingLayout::DumpListOfModules()
calls dyld API, which hangs on trying to take lock
```
Resulting in:
* Thread 2 has internal TSan mutex, blocked on dyld lock
* Thread 4 has dyld lock, blocked on internal TSan mutex

The fix prevents this situation by not intercepting any of the calls
originating from `MemoryMappingLayout::DumpListOfModules()`.

Stack traces for deadlock between ReportRace() and dlopen() interceptor:
```
thread #2, queue = 'com.apple.root.default-qos'
  frame #0: libsystem_kernel.dylib
  frame #1: libclang_rt.tsan_osx_dynamic.dylib`::wrap_os_unfair_lock_lock_with_options(lock=<unavailable>, options=<unavailable>) at tsan_interceptors_mac.cpp:306:3
  frame #2: dyld`dyld4::RuntimeLocks::withLoadersReadLock(this=0x000000016f21b1e0, work=0x00000001814523c0) block_pointer) at DyldRuntimeState.cpp:227:28
  frame #3: dyld`dyld4::APIs::_dyld_get_image_header(this=0x0000000101012a20, imageIndex=614) at DyldAPIs.cpp:240:11
  frame #4: libclang_rt.tsan_osx_dynamic.dylib`__sanitizer::MemoryMappingLayout::CurrentImageHeader(this=<unavailable>) at sanitizer_procmaps_mac.cpp:391:35
  frame #5: libclang_rt.tsan_osx_dynamic.dylib`__sanitizer::MemoryMappingLayout::Next(this=0x000000016f2a2800, segment=0x000000016f2a2738) at sanitizer_procmaps_mac.cpp:397:51
  frame #6: libclang_rt.tsan_osx_dynamic.dylib`__sanitizer::MemoryMappingLayout::DumpListOfModules(this=0x000000016f2a2800, modules=0x00000001011000a0) at sanitizer_procmaps_mac.cpp:460:10
  frame #7: libclang_rt.tsan_osx_dynamic.dylib`__sanitizer::ListOfModules::init(this=0x00000001011000a0) at sanitizer_mac.cpp:610:18
  frame #8: libclang_rt.tsan_osx_dynamic.dylib`__sanitizer::Symbolizer::FindModuleForAddress(unsigned long) [inlined] __sanitizer::Symbolizer::RefreshModules(this=0x0000000101100078) at sanitizer_symbolizer_libcdep.cpp:185:12
  frame #9: libclang_rt.tsan_osx_dynamic.dylib`__sanitizer::Symbolizer::FindModuleForAddress(this=0x0000000101100078, address=6465454512) at sanitizer_symbolizer_libcdep.cpp:204:5
  frame #10: libclang_rt.tsan_osx_dynamic.dylib`__sanitizer::Symbolizer::SymbolizePC(this=0x0000000101100078, addr=6465454512) at sanitizer_symbolizer_libcdep.cpp:88:15
  frame #11: libclang_rt.tsan_osx_dynamic.dylib`__tsan::SymbolizeCode(addr=6465454512) at tsan_symbolize.cpp:106:35
  frame #12: libclang_rt.tsan_osx_dynamic.dylib`__tsan::SymbolizeStack(trace=StackTrace @ 0x0000600002d66d00) at tsan_rtl_report.cpp:112:28
  frame #13: libclang_rt.tsan_osx_dynamic.dylib`__tsan::ScopedReportBase::AddMemoryAccess(this=0x000000016f2a2a90, addr=4381057136, external_tag=<unavailable>, s=<unavailable>, tid=<unavailable>, stack=<unavailable>, mset=0x00000001012fc310) at tsan_rtl_report.cpp:190:16
  frame #14: libclang_rt.tsan_osx_dynamic.dylib`__tsan::ReportRace(thr=0x00000001012fc000, shadow_mem=0x000008020a4340e0, cur=<unavailable>, old=<unavailable>, typ0=1) at tsan_rtl_report.cpp:795:9
  frame #15: libclang_rt.tsan_osx_dynamic.dylib`__tsan::DoReportRace(thr=0x00000001012fc000, shadow_mem=0x000008020a4340e0, cur=Shadow @ x22, old=Shadow @ 0x0000600002d6b4f0, typ=1) at tsan_rtl_access.cpp:166:3
  frame #16: libclang_rt.tsan_osx_dynamic.dylib`::__tsan_read8(void *) at tsan_rtl_access.cpp:220:5
  frame #17: libclang_rt.tsan_osx_dynamic.dylib`::__tsan_read8(void *) [inlined] __tsan::MemoryAccess(thr=0x00000001012fc000, pc=<unavailable>, addr=<unavailable>, size=8, typ=1) at tsan_rtl_access.cpp:442:3
  frame #18: libclang_rt.tsan_osx_dynamic.dylib`::__tsan_read8(addr=<unavailable>) at tsan_interface.inc:34:3
  <call into TSan from from instrumented code>

thread #4, queue = 'com.apple.dock.fullscreen'
  frame #0:  libsystem_kernel.dylib
  frame #1:  libclang_rt.tsan_osx_dynamic.dylib`__sanitizer::FutexWait(p=<unavailable>, cmp=<unavailable>) at sanitizer_mac.cpp:540:3
  frame #2:  libclang_rt.tsan_osx_dynamic.dylib`__sanitizer::Semaphore::Wait(this=<unavailable>) at sanitizer_mutex.cpp:35:7
  frame #3:  libclang_rt.tsan_osx_dynamic.dylib`__sanitizer::Mutex::Lock(this=0x0000000102992a80) at sanitizer_mutex.h:196:18
  frame #4:  libclang_rt.tsan_osx_dynamic.dylib`__tsan::ScopedInterceptor::~ScopedInterceptor() [inlined] __sanitizer::GenericScopedLock<__sanitizer::Mutex>::GenericScopedLock(this=<unavailable>, mu=0x0000000102992a80) at sanitizer_mutex.h:383:10
  frame #5:  libclang_rt.tsan_osx_dynamic.dylib`__tsan::ScopedInterceptor::~ScopedInterceptor() [inlined] __sanitizer::GenericScopedLock<__sanitizer::Mutex>::GenericScopedLock(this=<unavailable>, mu=0x0000000102992a80) at sanitizer_mutex.h:382:77
  frame #6:  libclang_rt.tsan_osx_dynamic.dylib`__tsan::ScopedInterceptor::~ScopedInterceptor() at tsan_rtl.h:708:10
  frame #7:  libclang_rt.tsan_osx_dynamic.dylib`__tsan::ScopedInterceptor::~ScopedInterceptor() [inlined] __tsan::TryTraceFunc(thr=0x000000010f084000, pc=0) at tsan_rtl.h:751:7
  frame #8:  libclang_rt.tsan_osx_dynamic.dylib`__tsan::ScopedInterceptor::~ScopedInterceptor() [inlined] __tsan::FuncExit(thr=0x000000010f084000) at tsan_rtl.h:798:7
  frame #9:  libclang_rt.tsan_osx_dynamic.dylib`__tsan::ScopedInterceptor::~ScopedInterceptor(this=0x000000016f3ba280) at tsan_interceptors_posix.cpp:300:5
  frame #10: libclang_rt.tsan_osx_dynamic.dylib`__tsan::ScopedInterceptor::~ScopedInterceptor(this=<unavailable>) at tsan_interceptors_posix.cpp:293:41
  frame #11: libclang_rt.tsan_osx_dynamic.dylib`::wrap_os_unfair_lock_lock_with_options(lock=0x000000016f21b1e8, options=OS_UNFAIR_LOCK_NONE) at tsan_interceptors_mac.cpp:310:1
  frame #12: dyld`dyld4::RuntimeLocks::withLoadersReadLock(this=0x000000016f21b1e0, work=0x00000001814525d4) block_pointer) at DyldRuntimeState.cpp:227:28
  frame #13: dyld`dyld4::APIs::_dyld_get_image_vmaddr_slide(this=0x0000000101012a20, imageIndex=412) at DyldAPIs.cpp:273:11
  frame #14: libclang_rt.tsan_osx_dynamic.dylib`__sanitizer::MemoryMappingLayout::Next(__sanitizer::MemoryMappedSegment*) at sanitizer_procmaps_mac.cpp:286:17
  frame #15: libclang_rt.tsan_osx_dynamic.dylib`__sanitizer::MemoryMappingLayout::Next(this=0x000000016f3ba560, segment=0x000000016f3ba498) at sanitizer_procmaps_mac.cpp:432:15
  frame #16: libclang_rt.tsan_osx_dynamic.dylib`__sanitizer::MemoryMappingLayout::DumpListOfModules(this=0x000000016f3ba560, modules=0x000000016f3ba618) at sanitizer_procmaps_mac.cpp:460:10
  frame #17: libclang_rt.tsan_osx_dynamic.dylib`__sanitizer::ListOfModules::init(this=0x000000016f3ba618) at sanitizer_mac.cpp:610:18
  frame #18: libclang_rt.tsan_osx_dynamic.dylib`__sanitizer::LibIgnore::OnLibraryLoaded(this=0x0000000101f3aa40, name="<some library>") at sanitizer_libignore.cpp:54:11
  frame #19: libclang_rt.tsan_osx_dynamic.dylib`::wrap_dlopen(filename="<some library>", flag=<unavailable>) at sanitizer_common_interceptors.inc:6466:3
  <library code>
```

rdar://106766395

Differential Revision: https://reviews.llvm.org/D146593
lanza pushed a commit that referenced this pull request Jul 6, 2023
Allow specifying 'nomerge' attribute for function pointers,
e.g. like in the following C code:

    extern void (*foo)(void) __attribute__((nomerge));
    void bar(long i) {
      if (i)
        foo();
      else
        foo();
    }

With the goal to attach 'nomerge' to both calls done through 'foo':

    @foo = external local_unnamed_addr global ptr, align 8
    define dso_local void @bar(i64 noundef %i) local_unnamed_addr #0 {
      ; ...
      %0 = load ptr, ptr @foo, align 8, !tbaa !5
      ; ...
    if.then:
      tail call void %0() #1
      br label %if.end
    if.else:
      tail call void %0() #1
      br label %if.end
    if.end:
      ret void
    }
    ; ...
    attributes #1 = { nomerge ... }

Report a warning in case if 'nomerge' is specified for a variable that
is not a function pointer, e.g.:

    t.c:2:22: warning: 'nomerge' attribute is ignored because 'j' is not a function pointer [-Wignored-attributes]
        2 | int j __attribute__((nomerge));
          |                      ^

The intended use-case is for BPF backend.

BPF provides a sort of "standard library" functions that are called
helpers. BPF also verifies usage of these helpers before program
execution. Because of limitations of verification / runtime model it
is important to keep calls to some of such helpers from merging.

An example could be found by the link [1], there input C code:

     if (data_end - data > 1024) {
         bpf_for_each_map_elem(&map1, cb, &cb_data, 0);
     } else {
         bpf_for_each_map_elem(&map2, cb, &cb_data, 0);
     }

Is converted to bytecode equivalent to:

     if (data_end - data > 1024)
       tmp = &map1;
     else
       tmp = &map2;
     bpf_for_each_map_elem(tmp, cb, &cb_data, 0);

However, BPF verification/runtime requires to use the same map address
for each particular `bpf_for_each_map_elem()` call.

The 'nomerge' attribute is a perfect match for this situation, but
unfortunately BPF helpers are declared as pointers to functions:

    static long (*bpf_for_each_map_elem)(void *map, ...) = (void *) 164;

Hence, this commit, allowing to use 'nomerge' for function pointers.

[1] https://lore.kernel.org/bpf/[email protected]/

Differential Revision: https://reviews.llvm.org/D152986
lanza pushed a commit that referenced this pull request Jul 6, 2023
Running this on Amazon Ubuntu the final backtrace is:
```
(lldb) thread backtrace
* thread #1, name = 'a.out', stop reason = breakpoint 1.1
  * frame #0: 0x0000aaaaaaaa07d0 a.out`func_c at main.c:10:3
    frame #1: 0x0000aaaaaaaa07c4 a.out`func_b at main.c:14:3
    frame #2: 0x0000aaaaaaaa07b4 a.out`func_a at main.c:18:3
    frame #3: 0x0000aaaaaaaa07a4 a.out`main(argc=<unavailable>, argv=<unavailable>) at main.c:22:3
    frame #4: 0x0000fffff7b373fc libc.so.6`___lldb_unnamed_symbol2962 + 108
    frame #5: 0x0000fffff7b374cc libc.so.6`__libc_start_main + 152
    frame #6: 0x0000aaaaaaaa06b0 a.out`_start + 48
```
This causes the test to fail because of the extra ___lldb_unnamed_symbol2962 frame
(an inlined function?).

To fix this, strictly check all the frames in main.c then for the rest
just check we find __libc_start_main and _start in that order regardless
of other frames in between.

Reviewed By: omjavaid

Differential Revision: https://reviews.llvm.org/D154204
lanza pushed a commit that referenced this pull request Dec 20, 2023
… on (#74207)

lld string tail merging interacts badly with ASAN on Windows, as is
reported in llvm/llvm-project#62078.
A similar error was found when building LLVM with
`-DLLVM_USE_SANITIZER=Address`:
```console
[2/2] Building GenVT.inc...
FAILED: include/llvm/CodeGen/GenVT.inc C:/Dev/llvm-project/Build_asan/include/llvm/CodeGen/GenVT.inc
cmd.exe /C "cd /D C:\Dev\llvm-project\Build_asan && C:\Dev\llvm-project\Build_asan\bin\llvm-min-tblgen.exe -gen-vt -I C:/Dev/llvm-project/llvm/include/llvm/CodeGen -IC:/Dev/llvm-project/Build_asan/include -IC:/Dev/llvm-project/llvm/include C:/Dev/llvm-project/llvm/include/llvm/CodeGen/ValueTypes.td --write-if-changed -o include/llvm/CodeGen/GenVT.inc -d include/llvm/CodeGen/GenVT.inc.d"       
=================================================================
==31944==ERROR: AddressSanitizer: global-buffer-overflow on address 0x7ff6cff80d20 at pc 0x7ff6cfcc7378 bp 0x00e8bcb8e990 sp 0x00e8bcb8e9d8
READ of size 1 at 0x7ff6cff80d20 thread T0
    #0 0x7ff6cfcc7377 in strlen (C:\Dev\llvm-project\Build_asan\bin\llvm-min-tblgen.exe+0x1400a7377)
    #1 0x7ff6cfde50c2 in operator delete(void *, unsigned __int64) (C:\Dev\llvm-project\Build_asan\bin\llvm-min-tblgen.exe+0x1401c50c2)
    #2 0x7ff6cfdd75ef in operator delete(void *, unsigned __int64) (C:\Dev\llvm-project\Build_asan\bin\llvm-min-tblgen.exe+0x1401b75ef)
    #3 0x7ff6cfde59f9 in operator delete(void *, unsigned __int64) (C:\Dev\llvm-project\Build_asan\bin\llvm-min-tblgen.exe+0x1401c59f9)
    #4 0x7ff6cff03f6c in operator delete(void *, unsigned __int64) (C:\Dev\llvm-project\Build_asan\bin\llvm-min-tblgen.exe+0x1402e3f6c)
    #5 0x7ff6cfefbcbc in operator delete(void *, unsigned __int64) (C:\Dev\llvm-project\Build_asan\bin\llvm-min-tblgen.exe+0x1402dbcbc)
    #6 0x7ffb7f247343  (C:\WINDOWS\System32\KERNEL32.DLL+0x180017343)
    #7 0x7ffb800826b0  (C:\WINDOWS\SYSTEM32\ntdll.dll+0x1800526b0)

0x7ff6cff80d20 is located 31 bytes after global variable '"#error \"ArgKind is not defined\"\n"...' defined in 'C:\Dev\llvm-project\llvm\utils\TableGen\IntrinsicEmitter.cpp' (0x7ff6cff80ce0) of size 33
  '"#error \"ArgKind is not defined\"\n"...' is ascii string '#error "ArgKind is not defined"
'
0x7ff6cff80d20 is located 0 bytes inside of global variable '""' defined in 'C:\Dev\llvm-project\llvm\utils\TableGen\IntrinsicEmitter.cpp' (0x7ff6cff80d20) of size 1
  '""' is ascii string ''
SUMMARY: AddressSanitizer: global-buffer-overflow (C:\Dev\llvm-project\Build_asan\bin\llvm-min-tblgen.exe+0x1400a7377) in strlen
Shadow bytes around the buggy address:
  0x7ff6cff80a80: 01 f9 f9 f9 f9 f9 f9 f9 00 00 00 00 01 f9 f9 f9
  0x7ff6cff80b00: f9 f9 f9 f9 00 00 00 00 00 00 00 00 01 f9 f9 f9
  0x7ff6cff80b80: f9 f9 f9 f9 00 00 00 00 01 f9 f9 f9 f9 f9 f9 f9
  0x7ff6cff80c00: 00 00 00 00 01 f9 f9 f9 f9 f9 f9 f9 00 00 00 00
  0x7ff6cff80c80: 00 00 00 00 01 f9 f9 f9 f9 f9 f9 f9 00 00 00 00
=>0x7ff6cff80d00: 01 f9 f9 f9[f9]f9 f9 f9 00 00 00 00 00 00 00 00
  0x7ff6cff80d80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x7ff6cff80e00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x7ff6cff80e80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x7ff6cff80f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x7ff6cff80f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
Shadow byte legend (one shadow byte represents 8 application bytes):
  Addressable:           00
  Partially addressable: 01 02 03 04 05 06 07
  Heap left redzone:       fa
  Freed heap region:       fd
  Stack left redzone:      f1
  Stack mid redzone:       f2
  Stack right redzone:     f3
  Stack after return:      f5
  Stack use after scope:   f8
  Global redzone:          f9
  Global init order:       f6
  Poisoned by user:        f7
  Container overflow:      fc
  Array cookie:            ac
  Intra object redzone:    bb
  ASan internal:           fe
  Left alloca redzone:     ca
  Right alloca redzone:    cb
==31944==ABORTING
```
This is reproducible with the 17.0.3 release:
```console
$ clang-cl --version
clang version 17.0.3
Target: x86_64-pc-windows-msvc
Thread model: posix
InstalledDir: C:\Program Files\LLVM\bin
$ cmake -S llvm -B Build -G Ninja -DLLVM_USE_SANITIZER=Address -DCMAKE_C_COMPILER=clang-cl -DCMAKE_CXX_COMPILER=clang-cl -DCMAKE_MSVC_RUNTIME_LIBRARY=MultiThreaded -DCMAKE_BUILD_TYPE=Release
$ cd Build
$ ninja all
```
lanza pushed a commit that referenced this pull request Dec 20, 2023
Internal builds of the unittests with msan flagged mempcpy_test.

    ==6862==WARNING: MemorySanitizer: use-of-uninitialized-value
#0 0x55e34d7d734a in length
llvm-project/libc/src/__support/CPP/string_view.h:41:11
#1 0x55e34d7d734a in string_view
llvm-project/libc/src/__support/CPP/string_view.h:71:24
#2 0x55e34d7d734a in
__llvm_libc_9999_0_0_git::testing::Test::testStrEq(char const*, char
const*, char const*, char const*,
__llvm_libc_9999_0_0_git::testing::internal::Location)
llvm-project/libc/test/UnitTest/LibcTest.cpp:284:13
#3 0x55e34d7d4e09 in LlvmLibcMempcpyTest_Simple::Run()
llvm-project/libc/test/src/string/mempcpy_test.cpp:20:3
#4 0x55e34d7d6dff in
__llvm_libc_9999_0_0_git::testing::Test::runTests(char const*)
llvm-project/libc/test/UnitTest/LibcTest.cpp:133:8
#5 0x55e34d7d86e0 in main
llvm-project/libc/test/UnitTest/LibcTestMain.cpp:21:10

SUMMARY: MemorySanitizer: use-of-uninitialized-value
llvm-project/libc/src/__support/CPP/string_view.h:41:11 in length

What's going on here is that mempcpy_test.cpp's Simple test is using
ASSERT_STREQ with a partially initialized char array. ASSERT_STREQ calls
Test::testStrEq which constructs a cpp:string_view. That constructor
calls the
private method cpp::string_view::length. When built with msan, the loop
is
transformed into multi-byte access, which then fails upon access.

I took a look at libc++'s __constexpr_strlen which just calls
__builtin_strlen(). Replacing the implementation of
cpp::string_view::length
with a call to __builtin_strlen() may still result in out of bounds
access when
the test is built with msan.

It's not safe to use ASSERT_STREQ with a partially initialized array.
Initialize the whole array so that the test passes.
lanza pushed a commit that referenced this pull request Dec 20, 2023
We'd like a way to select the current thread by its thread ID (rather
than its internal LLDB thread index).

This PR adds a `-t` option (`--thread_id` long option) that tells the
`thread select` command to interpret the `<thread-index>` argument as a
thread ID.

Here's an example of it working:
```
michristensen@devbig356 llvm/llvm-project (thread-select-tid) » ../Debug/bin/lldb ~/scratch/cpp/threading/a.out
(lldb) target create "/home/michristensen/scratch/cpp/threading/a.out"
Current executable set to '/home/michristensen/scratch/cpp/threading/a.out' (x86_64).
(lldb) b 18
Breakpoint 1: where = a.out`main + 80 at main.cpp:18:12, address = 0x0000000000000850
(lldb) run
Process 215715 launched: '/home/michristensen/scratch/cpp/threading/a.out' (x86_64)
This is a thread, i=1
This is a thread, i=2
This is a thread, i=3
This is a thread, i=4
This is a thread, i=5
Process 215715 stopped
* thread #1, name = 'a.out', stop reason = breakpoint 1.1
    frame #0: 0x0000555555400850 a.out`main at main.cpp:18:12
   15     for (int i = 0; i < 5; i++) {
   16       pthread_create(&thread_ids[i], NULL, foo, NULL);
   17     }
-> 18     for (int i = 0; i < 5; i++) {
   19       pthread_join(thread_ids[i], NULL);
   20     }
   21     return 0;
(lldb) thread select 2
* thread #2, name = 'a.out'
    frame #0: 0x00007ffff68f9918 libc.so.6`__nanosleep + 72
libc.so.6`__nanosleep:
->  0x7ffff68f9918 <+72>: cmpq   $-0x1000, %rax ; imm = 0xF000
    0x7ffff68f991e <+78>: ja     0x7ffff68f9952 ; <+130>
    0x7ffff68f9920 <+80>: movl   %edx, %edi
    0x7ffff68f9922 <+82>: movl   %eax, 0xc(%rsp)
(lldb) thread info
thread #2: tid = 216047, 0x00007ffff68f9918 libc.so.6`__nanosleep + 72, name = 'a.out'

(lldb) thread list
Process 215715 stopped
  thread #1: tid = 215715, 0x0000555555400850 a.out`main at main.cpp:18:12, name = 'a.out', stop reason = breakpoint 1.1
* thread #2: tid = 216047, 0x00007ffff68f9918 libc.so.6`__nanosleep + 72, name = 'a.out'
  thread #3: tid = 216048, 0x00007ffff68f9918 libc.so.6`__nanosleep + 72, name = 'a.out'
  thread #4: tid = 216049, 0x00007ffff68f9918 libc.so.6`__nanosleep + 72, name = 'a.out'
  thread #5: tid = 216050, 0x00007ffff68f9918 libc.so.6`__nanosleep + 72, name = 'a.out'
  thread #6: tid = 216051, 0x00007ffff68f9918 libc.so.6`__nanosleep + 72, name = 'a.out'
(lldb) thread select 215715
error: invalid thread #215715.
(lldb) thread select -t 215715
* thread #1, name = 'a.out', stop reason = breakpoint 1.1
    frame #0: 0x0000555555400850 a.out`main at main.cpp:18:12
   15     for (int i = 0; i < 5; i++) {
   16       pthread_create(&thread_ids[i], NULL, foo, NULL);
   17     }
-> 18     for (int i = 0; i < 5; i++) {
   19       pthread_join(thread_ids[i], NULL);
   20     }
   21     return 0;
(lldb) thread select -t 216051
* thread #6, name = 'a.out'
    frame #0: 0x00007ffff68f9918 libc.so.6`__nanosleep + 72
libc.so.6`__nanosleep:
->  0x7ffff68f9918 <+72>: cmpq   $-0x1000, %rax ; imm = 0xF000
    0x7ffff68f991e <+78>: ja     0x7ffff68f9952 ; <+130>
    0x7ffff68f9920 <+80>: movl   %edx, %edi
    0x7ffff68f9922 <+82>: movl   %eax, 0xc(%rsp)
(lldb) thread select 3
* thread #3, name = 'a.out'
    frame #0: 0x00007ffff68f9918 libc.so.6`__nanosleep + 72
libc.so.6`__nanosleep:
->  0x7ffff68f9918 <+72>: cmpq   $-0x1000, %rax ; imm = 0xF000
    0x7ffff68f991e <+78>: ja     0x7ffff68f9952 ; <+130>
    0x7ffff68f9920 <+80>: movl   %edx, %edi
    0x7ffff68f9922 <+82>: movl   %eax, 0xc(%rsp)
(lldb) thread select -t 216048
* thread #3, name = 'a.out'
    frame #0: 0x00007ffff68f9918 libc.so.6`__nanosleep + 72
libc.so.6`__nanosleep:
->  0x7ffff68f9918 <+72>: cmpq   $-0x1000, %rax ; imm = 0xF000
    0x7ffff68f991e <+78>: ja     0x7ffff68f9952 ; <+130>
    0x7ffff68f9920 <+80>: movl   %edx, %edi
    0x7ffff68f9922 <+82>: movl   %eax, 0xc(%rsp)
(lldb) thread select --thread_id 216048
* thread #3, name = 'a.out'
    frame #0: 0x00007ffff68f9918 libc.so.6`__nanosleep + 72
libc.so.6`__nanosleep:
->  0x7ffff68f9918 <+72>: cmpq   $-0x1000, %rax ; imm = 0xF000
    0x7ffff68f991e <+78>: ja     0x7ffff68f9952 ; <+130>
    0x7ffff68f9920 <+80>: movl   %edx, %edi
    0x7ffff68f9922 <+82>: movl   %eax, 0xc(%rsp)
(lldb) help thread select
Change the currently selected thread.

Syntax: thread select <cmd-options> <thread-index>

Command Options Usage:
  thread select [-t] <thread-index>

       -t ( --thread_id )
            Provide a thread ID instead of a thread index.

     This command takes options and free-form arguments.  If your arguments
     resemble option specifiers (i.e., they start with a - or --), you must use
     ' -- ' between the end of the command options and the beginning of the
     arguments.
(lldb) c
Process 215715 resuming
Process 215715 exited with status = 0 (0x00000000)
```
lanza pushed a commit that referenced this pull request Mar 21, 2024
This reverts commit daebe5c.

This commit causes the following asan issue:

```
<snip>/llvm-project/build/bin/mlir-opt <snip>/llvm-project/mlir/test/Dialect/XeGPU/XeGPUOps.mlir | <snip>/llvm-project/build/bin/FileCheck <snip>/llvm-project/mlir/test/Dialect/XeGPU/XeGPUOps.mlir
# executed command: <snip>/llvm-project/build/bin/mlir-opt <snip>/llvm-project/mlir/test/Dialect/XeGPU/XeGPUOps.mlir
# .---command stderr------------
# | =================================================================
# | ==2772558==ERROR: AddressSanitizer: stack-use-after-return on address 0x7fd2c2c42b90 at pc 0x55e406d54614 bp 0x7ffc810e4070 sp 0x7ffc810e4068
# | READ of size 8 at 0x7fd2c2c42b90 thread T0
# |     #0 0x55e406d54613 in operator()<long int const*> /usr/include/c++/13/bits/predefined_ops.h:318
# |     #1 0x55e406d54613 in __count_if<long int const*, __gnu_cxx::__ops::_Iter_pred<mlir::verifyListOfOperandsOrIntegers(Operation*, llvm::StringRef, unsigned int, llvm::ArrayRef<long int>, ValueRange)::<lambda(int64_t)> > > /usr/include/c++/13/bits/stl_algobase.h:2125
# |     #2 0x55e406d54613 in count_if<long int const*, mlir::verifyListOfOperandsOrIntegers(Operation*, 
...
```
lanza pushed a commit that referenced this pull request Mar 21, 2024
…oint. (#83821)"

This reverts commit c2c1e6e. It creates
a use after free.

==8342==ERROR: AddressSanitizer: heap-use-after-free on address 0x50f000001760 at pc 0x55b9fb84a8fb bp 0x7ffc18468a10 sp 0x7ffc18468a08
READ of size 1 at 0x50f000001760 thread T0
 #0 0x55b9fb84a8fa in dropPoisonGeneratingFlags llvm/lib/Transforms/Vectorize/VPlan.h:1040:13
 #1 0x55b9fb84a8fa in llvm::VPlanTransforms::dropPoisonGeneratingRecipes(llvm::VPlan&, llvm::function_ref<bool (llvm::BasicBlock*)>)::$_0::operator()(llvm::VPRecipeBase*) const llvm/lib/Transforms/Vectorize/VPlanTransforms.cpp:1236:23
 #2 0x55b9fb84a196 in llvm::VPlanTransforms::dropPoisonGeneratingRecipes(llvm::VPlan&, llvm::function_ref<bool (llvm::BasicBlock*)>) llvm/lib/Transforms/Vectorize/VPlanTransforms.cpp

Can be reproduced with asan on
Transforms/LoopVectorize/AArch64/sve-interleaved-masked-accesses.ll
Transforms/LoopVectorize/X86/pr81872.ll
Transforms/LoopVectorize/X86/x86-interleaved-accesses-masked-group.ll
sitio-couto added a commit to sitio-couto/clangir that referenced this pull request Apr 4, 2024
sitio-couto added a commit to sitio-couto/clangir that referenced this pull request Apr 4, 2024
sitio-couto added a commit to sitio-couto/clangir that referenced this pull request May 3, 2024
sitio-couto added a commit to sitio-couto/clangir that referenced this pull request May 6, 2024
lanza pushed a commit that referenced this pull request Jun 21, 2024
…on (#94752)

Fixes #62925.

The following code:
```cpp
#include <map>

int main() {
   std::map m1 = {std::pair{"foo", 2}, {"bar", 3}}; // guide #2
   std::map m2(m1.begin(), m1.end()); // guide #1
}
```
Is rejected by clang, but accepted by both gcc and msvc:
https://godbolt.org/z/6v4fvabb5 .

So basically CTAD with copy-list-initialization is rejected.

Note that this exact code is also used in a cppreference article:
https://en.cppreference.com/w/cpp/container/map/deduction_guides

I checked the C++11 and C++20 standard drafts to see whether suppressing
user conversion is the correct thing to do for user conversions. Based
on the standard I don't think that it is correct.

```
13.3.1.4 Copy-initialization of class by user-defined conversion [over.match.copy]
Under the conditions specified in 8.5, as part of a copy-initialization of an object of class type, a user-defined
conversion can be invoked to convert an initializer expression to the type of the object being initialized.
Overload resolution is used to select the user-defined conversion to be invoked
```
So we could use user defined conversions according to the standard.

```
If a narrowing conversion is required to initialize any of the elements, the
program is ill-formed.
```
We should not do narrowing.

```
In copy-list-initialization, if an explicit constructor is chosen, the initialization is ill-formed.
```
We should not use explicit constructors.
lanza pushed a commit that referenced this pull request Jun 21, 2024
`rethrow` instruction is a terminator, but when when its DAG is built in
`SelectionDAGBuilder` in a custom routine, it was NOT treated as such.

```ll
rethrow:                                          ; preds = %catch.start
  invoke void @llvm.wasm.rethrow() #1 [ "funclet"(token %1) ]
          to label %unreachable unwind label %ehcleanup

ehcleanup:                                        ; preds = %rethrow, %catch.dispatch
  %tmp = phi i32 [ 10, %catch.dispatch ], [ 20, %rethrow ]
  ...
```

In this bitcode, because of the `phi`, a `CONST_I32` will be created in
the `rethrow` BB. Without this patch, the DAG for the `rethrow` BB looks
like this:
```
  t0: ch,glue = EntryToken
      t3: ch = CopyToReg t0, Register:i32 %9, Constant:i32<20>
      t5: ch = llvm.wasm.rethrow t0, TargetConstant:i32<12161>
    t6: ch = TokenFactor t3, t5
  t8: ch = br t6, BasicBlock:ch<unreachable 0x562532e43c50>
```
Note that `CopyToReg` and `llvm.wasm.rethrow` don't have dependence so
either can come first in the selected code, which can result in the code
like
```mir
bb.3.rethrow:
  RETHROW 0, implicit-def dead $arguments
  %9:i32 = CONST_I32 20, implicit-def dead $arguments
  BR %bb.6, implicit-def dead $arguments
```

After this patch, `llvm.wasm.rethrow` is treated as a terminator, and
the DAG will look like
```
        t0: ch,glue = EntryToken
      t3: ch = CopyToReg t0, Register:i32 %9, Constant:i32<20>
    t5: ch = llvm.wasm.rethrow t3, TargetConstant:i32<12161>
  t7: ch = br t5, BasicBlock:ch<unreachable 0x5555e3d32c70>
```
Note that now `rethrow` takes a token from `CopyToReg`, so `rethrow` has
to come after `CopyToReg`. And the resulting code will be
```mir
bb.3.rethrow:
  %9:i32 = CONST_I32 20, implicit-def dead $arguments
  RETHROW 0, implicit-def dead $arguments
  BR %bb.6, implicit-def dead $arguments
```

I'm not very familiar with the internals of `getRoot` vs.
`getControlRoot`, but other terminator instructions seem to use the
latter, and using it for `rethrow` too worked.
bcardosolopes pushed a commit that referenced this pull request Sep 27, 2024
…no override (#893)

As title. 
The test case used is abort(), but it is from the real code. 
Notice: Since CIR implementation for NoReturn Call is pending to
implement, the generated llvm code is like:
`define dso_local void @test() #1  {
  call void @abort(), !dbg !8
  ret void
}`
which is not right, right code should be like, 
`
`define dso_local void @test() #1  {
  call void @abort(), !dbg !8
  unreachable
}`
`
Still send this PR as Noreturn implementation is a separate issue.
lanza pushed a commit that referenced this pull request Oct 2, 2024
…104148)

`hasOperands` does not always execute matchers in the order they are
written. This can cause issue in code using bindings when one operand
matcher is relying on a binding set by the other. With this change, the
first matcher present in the code is always executed first and any
binding it sets are available to the second matcher.

Simple example with current version (1 match) and new version (2
matches):
```bash
> cat tmp.cpp
int a = 13;
int b = ((int) a) - a;
int c = a - ((int) a);

> clang-query tmp.cpp
clang-query> set traversal IgnoreUnlessSpelledInSource
clang-query> m binaryOperator(hasOperands(cStyleCastExpr(has(declRefExpr(hasDeclaration(valueDecl().bind("d"))))), declRefExpr(hasDeclaration(valueDecl(equalsBoundNode("d"))))))

Match #1:

tmp.cpp:1:1: note: "d" binds here
int a = 13;
^~~~~~~~~~
tmp.cpp:2:9: note: "root" binds here
int b = ((int)a) - a;
        ^~~~~~~~~~~~
1 match.

> ./build/bin/clang-query tmp.cpp
clang-query> set traversal IgnoreUnlessSpelledInSource
clang-query> m binaryOperator(hasOperands(cStyleCastExpr(has(declRefExpr(hasDeclaration(valueDecl().bind("d"))))), declRefExpr(hasDeclaration(valueDecl(equalsBoundNode("d"))))))

Match #1:

tmp.cpp:1:1: note: "d" binds here
    1 | int a = 13;
      | ^~~~~~~~~~
tmp.cpp:2:9: note: "root" binds here
    2 | int b = ((int)a) - a;
      |         ^~~~~~~~~~~~

Match #2:

tmp.cpp:1:1: note: "d" binds here
    1 | int a = 13;
      | ^~~~~~~~~~
tmp.cpp:3:9: note: "root" binds here
    3 | int c = a - ((int)a);
      |         ^~~~~~~~~~~~
2 matches.
```

If this should be documented or regression tested anywhere please let me
know where.
lanza pushed a commit that referenced this pull request Oct 2, 2024
Compilers and language runtimes often use helper functions that are
fundamentally uninteresting when debugging anything but the
compiler/runtime itself. This patch introduces a user-extensible
mechanism that allows for these frames to be hidden from backtraces and
automatically skipped over when navigating the stack with `up` and
`down`.

This does not affect the numbering of frames, so `f <N>` will still
provide access to the hidden frames. The `bt` output will also print a
hint that frames have been hidden.

My primary motivation for this feature is to hide thunks in the Swift
programming language, but I'm including an example recognizer for
`std::function::operator()` that I wished for myself many times while
debugging LLDB.

rdar://126629381


Example output. (Yes, my proof-of-concept recognizer could hide even
more frames if we had a method that returned the function name without
the return type or I used something that isn't based off regex, but it's
really only meant as an example).

before:
```
(lldb) thread backtrace --filtered=false
* thread #1, queue = 'com.apple.main-thread', stop reason = breakpoint 1.1
  * frame #0: 0x0000000100001f04 a.out`foo(x=1, y=1) at main.cpp:4:10
    frame #1: 0x0000000100003a00 a.out`decltype(std::declval<int (*&)(int, int)>()(std::declval<int>(), std::declval<int>())) std::__1::__invoke[abi:se200000]<int (*&)(int, int), int, int>(__f=0x000000016fdff280, __args=0x000000016fdff224, __args=0x000000016fdff220) at invoke.h:149:25
    frame #2: 0x000000010000399c a.out`int std::__1::__invoke_void_return_wrapper<int, false>::__call[abi:se200000]<int (*&)(int, int), int, int>(__args=0x000000016fdff280, __args=0x000000016fdff224, __args=0x000000016fdff220) at invoke.h:216:12
    frame #3: 0x0000000100003968 a.out`std::__1::__function::__alloc_func<int (*)(int, int), std::__1::allocator<int (*)(int, int)>, int (int, int)>::operator()[abi:se200000](this=0x000000016fdff280, __arg=0x000000016fdff224, __arg=0x000000016fdff220) at function.h:171:12
    frame #4: 0x00000001000026bc a.out`std::__1::__function::__func<int (*)(int, int), std::__1::allocator<int (*)(int, int)>, int (int, int)>::operator()(this=0x000000016fdff278, __arg=0x000000016fdff224, __arg=0x000000016fdff220) at function.h:313:10
    frame #5: 0x0000000100003c38 a.out`std::__1::__function::__value_func<int (int, int)>::operator()[abi:se200000](this=0x000000016fdff278, __args=0x000000016fdff224, __args=0x000000016fdff220) const at function.h:430:12
    frame #6: 0x0000000100002038 a.out`std::__1::function<int (int, int)>::operator()(this= Function = foo(int, int) , __arg=1, __arg=1) const at function.h:989:10
    frame #7: 0x0000000100001f64 a.out`main(argc=1, argv=0x000000016fdff4f8) at main.cpp:9:10
    frame #8: 0x0000000183cdf154 dyld`start + 2476
(lldb) 
```

after

```
(lldb) bt
* thread #1, queue = 'com.apple.main-thread', stop reason = breakpoint 1.1
  * frame #0: 0x0000000100001f04 a.out`foo(x=1, y=1) at main.cpp:4:10
    frame #1: 0x0000000100003a00 a.out`decltype(std::declval<int (*&)(int, int)>()(std::declval<int>(), std::declval<int>())) std::__1::__invoke[abi:se200000]<int (*&)(int, int), int, int>(__f=0x000000016fdff280, __args=0x000000016fdff224, __args=0x000000016fdff220) at invoke.h:149:25
    frame #2: 0x000000010000399c a.out`int std::__1::__invoke_void_return_wrapper<int, false>::__call[abi:se200000]<int (*&)(int, int), int, int>(__args=0x000000016fdff280, __args=0x000000016fdff224, __args=0x000000016fdff220) at invoke.h:216:12
    frame #6: 0x0000000100002038 a.out`std::__1::function<int (int, int)>::operator()(this= Function = foo(int, int) , __arg=1, __arg=1) const at function.h:989:10
    frame #7: 0x0000000100001f64 a.out`main(argc=1, argv=0x000000016fdff4f8) at main.cpp:9:10
    frame #8: 0x0000000183cdf154 dyld`start + 2476
Note: Some frames were hidden by frame recognizers
```
lanza pushed a commit that referenced this pull request Oct 2, 2024
`JITDylibSearchOrderResolver` local variable can be destroyed before
completion of all callbacks. Capture it together with `Deps` in
`OnEmitted` callback.

Original error:

```
==2035==ERROR: AddressSanitizer: stack-use-after-return on address 0x7bebfa155b70 at pc 0x7ff2a9a88b4a bp 0x7bec08d51980 sp 0x7bec08d51978
READ of size 8 at 0x7bebfa155b70 thread T87 (tf_xla-cpu-llvm)
    #0 0x7ff2a9a88b49 in operator() llvm/lib/ExecutionEngine/Orc/RTDyldObjectLinkingLayer.cpp:55:58
    #1 0x7ff2a9a88b49 in __invoke<(lambda at llvm/lib/ExecutionEngine/Orc/RTDyldObjectLinkingLayer.cpp:55:9) &, const llvm::DenseMap<llvm::orc::JITDylib *, llvm::DenseSet<llvm::orc::SymbolStringPtr, llvm::DenseMapInfo<llvm::orc::SymbolStringPtr, void> >, llvm::DenseMapInfo<llvm::orc::JITDylib *, void>, llvm::detail::DenseMapPair<llvm::orc::JITDylib *, llvm::DenseSet<llvm::orc::SymbolStringPtr, llvm::DenseMapInfo<llvm::orc::SymbolStringPtr, void> > > > &> libcxx/include/__type_traits/invoke.h:149:25
    #2 0x7ff2a9a88b49 in __call<(lambda at llvm/lib/ExecutionEngine/Orc/RTDyldObjectLinkingLayer.cpp:55:9) &, const llvm::DenseMap<llvm::orc::JITDylib *, llvm::DenseSet<llvm::orc::SymbolStringPtr, llvm::DenseMapInfo<llvm::orc::SymbolStringPtr, void> >, llvm::DenseMapInfo<llvm::orc::JITDylib *, void>, llvm::detail::DenseMapPair<llvm::orc::JITDylib *, llvm::DenseSet<llvm::orc::SymbolStringPtr, llvm::DenseMapInfo<llvm::orc::SymbolStringPtr, void> > > > &> libcxx/include/__type_traits/invoke.h:224:5
    #3 0x7ff2a9a88b49 in operator() libcxx/include/__functional/function.h:210:12
    #4 0x7ff2a9a88b49 in void std::__u::__function::__policy_invoker<void (llvm::DenseMap<llvm::orc::JITDylib*, llvm::DenseSet<llvm::orc::SymbolStringPtr,
```
Hugobros3 pushed a commit to shady-gang/clangir that referenced this pull request Oct 2, 2024
…no override (llvm#893)

As title. 
The test case used is abort(), but it is from the real code. 
Notice: Since CIR implementation for NoReturn Call is pending to
implement, the generated llvm code is like:
`define dso_local void @test() llvm#1  {
  call void @abort(), !dbg !8
  ret void
}`
which is not right, right code should be like, 
`
`define dso_local void @test() llvm#1  {
  call void @abort(), !dbg !8
  unreachable
}`
`
Still send this PR as Noreturn implementation is a separate issue.
smeenai pushed a commit to smeenai/clangir that referenced this pull request Oct 9, 2024
…no override (llvm#893)

As title. 
The test case used is abort(), but it is from the real code. 
Notice: Since CIR implementation for NoReturn Call is pending to
implement, the generated llvm code is like:
`define dso_local void @test() llvm#1  {
  call void @abort(), !dbg !8
  ret void
}`
which is not right, right code should be like, 
`
`define dso_local void @test() llvm#1  {
  call void @abort(), !dbg !8
  unreachable
}`
`
Still send this PR as Noreturn implementation is a separate issue.
smeenai pushed a commit to smeenai/clangir that referenced this pull request Oct 9, 2024
…no override (llvm#893)

As title. 
The test case used is abort(), but it is from the real code. 
Notice: Since CIR implementation for NoReturn Call is pending to
implement, the generated llvm code is like:
`define dso_local void @test() llvm#1  {
  call void @abort(), !dbg !8
  ret void
}`
which is not right, right code should be like, 
`
`define dso_local void @test() llvm#1  {
  call void @abort(), !dbg !8
  unreachable
}`
`
Still send this PR as Noreturn implementation is a separate issue.
smeenai pushed a commit to smeenai/clangir that referenced this pull request Oct 9, 2024
…no override (llvm#893)

As title. 
The test case used is abort(), but it is from the real code. 
Notice: Since CIR implementation for NoReturn Call is pending to
implement, the generated llvm code is like:
`define dso_local void @test() llvm#1  {
  call void @abort(), !dbg !8
  ret void
}`
which is not right, right code should be like, 
`
`define dso_local void @test() llvm#1  {
  call void @abort(), !dbg !8
  unreachable
}`
`
Still send this PR as Noreturn implementation is a separate issue.
smeenai pushed a commit that referenced this pull request Oct 10, 2024
…ext is not fully initialized (#110481)

As this comment around target initialization implies:
```
  // This can be NULL if we don't know anything about the architecture or if
  // the target for an architecture isn't enabled in the llvm/clang that we
  // built
```

There are cases where we might fail to call `InitBuiltinTypes` when
creating the backing `ASTContext` for a `TypeSystemClang`. If that
happens, the builtins `QualType`s, e.g., `VoidPtrTy`/`IntTy`/etc., are
not initialized and dereferencing them as we do in
`GetBuiltinTypeForEncodingAndBitSize` (and other places) will lead to
nullptr-dereferences. Example backtrace:
```
(lldb) run
Assertion failed: (!isNull() && "Cannot retrieve a NULL type pointer"), function getCommonPtr, file Type.h, line 958.
Process 2680 stopped
* thread #15, name = '<lldb.process.internal-state(pid=2712)>', stop reason = hit program assert
    frame #4: 0x000000010cdf3cdc liblldb.20.0.0git.dylib`DWARFASTParserClang::ExtractIntFromFormValue(lldb_private::CompilerType const&, lldb_private::plugin::dwarf::DWARFFormValue const&) const (.cold.1) + 
liblldb.20.0.0git.dylib`DWARFASTParserClang::ParseObjCMethod(lldb_private::ObjCLanguage::MethodName const&, lldb_private::plugin::dwarf::DWARFDIE const&, lldb_private::CompilerType, ParsedDWARFTypeAttributes
, bool) (.cold.1):
->  0x10cdf3cdc <+0>:  stp    x29, x30, [sp, #-0x10]!
    0x10cdf3ce0 <+4>:  mov    x29, sp
    0x10cdf3ce4 <+8>:  adrp   x0, 545
    0x10cdf3ce8 <+12>: add    x0, x0, #0xa25 ; "ParseObjCMethod"
Target 0: (lldb) stopped.
(lldb) bt
* thread #15, name = '<lldb.process.internal-state(pid=2712)>', stop reason = hit program assert
    frame #0: 0x0000000180d08600 libsystem_kernel.dylib`__pthread_kill + 8
    frame #1: 0x0000000180d40f50 libsystem_pthread.dylib`pthread_kill + 288
    frame #2: 0x0000000180c4d908 libsystem_c.dylib`abort + 128
    frame #3: 0x0000000180c4cc1c libsystem_c.dylib`__assert_rtn + 284
  * frame #4: 0x000000010cdf3cdc liblldb.20.0.0git.dylib`DWARFASTParserClang::ExtractIntFromFormValue(lldb_private::CompilerType const&, lldb_private::plugin::dwarf::DWARFFormValue const&) const (.cold.1) + 
    frame #5: 0x0000000109d30acc liblldb.20.0.0git.dylib`lldb_private::TypeSystemClang::GetBuiltinTypeForEncodingAndBitSize(lldb::Encoding, unsigned long) + 1188
    frame #6: 0x0000000109aaaed4 liblldb.20.0.0git.dylib`DynamicLoaderMacOS::NotifyBreakpointHit(void*, lldb_private::StoppointCallbackContext*, unsigned long long, unsigned long long) + 384
```

This patch adds a one-time user-visible warning for when we fail to
initialize the AST to indicate that initialization went wrong for the
given target. Additionally, we add checks for whether one of the
`ASTContext` `QualType`s is invalid before dereferencing any builtin
types.

The warning would look as follows:
```
(lldb) target create "a.out"
Current executable set to 'a.out' (arm64).
(lldb) b main
warning: Failed to initialize builtin ASTContext types for target 'some-unknown-triple'. Printing variables may behave unexpectedly.
Breakpoint 1: where = a.out`main + 8 at stepping.cpp:5:14, address = 0x0000000100003f90
```

rdar://134869779
keryell pushed a commit to keryell/clangir that referenced this pull request Oct 19, 2024
…no override (llvm#893)

As title. 
The test case used is abort(), but it is from the real code. 
Notice: Since CIR implementation for NoReturn Call is pending to
implement, the generated llvm code is like:
`define dso_local void @test() llvm#1  {
  call void @abort(), !dbg !8
  ret void
}`
which is not right, right code should be like, 
`
`define dso_local void @test() llvm#1  {
  call void @abort(), !dbg !8
  unreachable
}`
`
Still send this PR as Noreturn implementation is a separate issue.
lanza pushed a commit that referenced this pull request Nov 4, 2024
When compiling for an SVE target we can use INDEX to generate constant
fixed-length step vectors, e.g.:
```
uint32x4_t foo() {
  return (uint32x4_t){0, 1, 2, 3};
}
```
Currently:
```
foo():
        adrp    x8, .LCPI1_0
        ldr     q0, [x8, :lo12:.LCPI1_0]
        ret
```
With INDEX:
```
foo():
        index   z0.s, #0, #1
        ret
```

The logic for this was already in `LowerBUILD_VECTOR`, though it was
hidden under a check for `!Subtarget->isNeonAvailable()`. This patch
refactors this to enable the corresponding code path unconditionally for
constant step vectors (as long as we can use SVE for them).
lanza pushed a commit that referenced this pull request Nov 4, 2024
…ates explicitly specialized for an implicitly instantiated class template specialization (#113464)

Consider the following:
```
template<typename T>
struct A {
  template<typename U>
  struct B {
    static constexpr int x = 0; // #1
  };

  template<typename U>
  struct B<U*> {
    static constexpr int x = 1; // #2
  };
};

template<>
template<typename U>
struct A<long>::B {
  static constexpr int x = 2; // #3
};

static_assert(A<short>::B<int>::y == 0); // uses #1
static_assert(A<short>::B<int*>::y == 1); // uses #2

static_assert(A<long>::B<int>::y == 2); // uses #3
static_assert(A<long>::B<int*>::y == 2); // uses #3
```

According to [temp.spec.partial.member] p2:
> If the primary member template is explicitly specialized for a given
(implicit) specialization of the enclosing class template, the partial
specializations of the member template are ignored for this
specialization of the enclosing class template.
If a partial specialization of the member template is explicitly
specialized for a given (implicit) specialization of the enclosing class
template, the primary member template and its other partial
specializations are still considered for this specialization of the
enclosing class template.

The example above fails to compile because we currently don't implement
[temp.spec.partial.member] p2. This patch implements the wording, fixing #51051.
lanza pushed a commit that referenced this pull request Nov 5, 2024
…no override (#893)

As title. 
The test case used is abort(), but it is from the real code. 
Notice: Since CIR implementation for NoReturn Call is pending to
implement, the generated llvm code is like:
`define dso_local void @test() #1  {
  call void @abort(), !dbg !8
  ret void
}`
which is not right, right code should be like, 
`
`define dso_local void @test() #1  {
  call void @abort(), !dbg !8
  unreachable
}`
`
Still send this PR as Noreturn implementation is a separate issue.
seven-mile pushed a commit to seven-mile/clangir that referenced this pull request Nov 13, 2024
We've found that basic profiling could help improving/optimizing when
developing clang-tidy checks.

This PR adds an extra command
```
set enable-profile (true|false)   Set whether to enable matcher profiling.
```
which enables profiling queries on each file.

Sample output:

```
$ cat test.cql
set enable-profile true
m binaryOperator(isExpansionInMainFile())

$ cat test.c
int test(int i, int j) {
  return i + j;
}

$ clang-query --track-memory -f test.cql test.c --

Match llvm#1:

{{.*}}/test.c:2:10: note: "root" binds here
    2 |   return i + j;
      |          ^~~~~
1 match.
===-------------------------------------------------------------------------===
                         clang-query matcher profiling
===-------------------------------------------------------------------------===
  Total Execution Time: 0.0000 seconds (0.0000 wall clock)

   ---User Time---   --System Time--   --User+System--   ---Wall Time---  ---Mem---  --- Name ---
   0.0000 (100.0%)   0.0000 (100.0%)   0.0000 (100.0%)   0.0000 (100.0%)        224  {{.*}}/test.c
   0.0000 (100.0%)   0.0000 (100.0%)   0.0000 (100.0%)   0.0000 (100.0%)        224  Total
```
seven-mile pushed a commit to seven-mile/clangir that referenced this pull request Nov 13, 2024
…vm#1… (#115376)

…15019)"

This reverts commit 9f79615.

This is breaking compiler-rt/lib/sanitizer_common/...

Author knows about the breakage.
seven-mile pushed a commit to seven-mile/clangir that referenced this pull request Nov 13, 2024
… depobj construct (#114221)

A codegen crash is occurring when a depend object was initialized with
omp_all_memory in the depobj directive.
llvm/llvm-project#114214
The root cause of issue looks to be the improper handling of the
dependency list when omp_all_memory was specified.

The change introduces the use of OMPTaskDataTy to manage dependencies.
The buildDependences function is called to construct the dependency
list, and the list is iterated over to emit and store the dependencies.

Reduced Test Case : 
```
#include <omp.h>

int main()

{ omp_depend_t obj; #pragma omp depobj(obj) depend(inout: omp_all_memory) }
```

```
 llvm#1 0x0000000003de6623 SignalHandler(int) Signals.cpp:0:0
 llvm#2 0x00007f8e4a6b990f (/lib64/libpthread.so.0+0x1690f)
 llvm#3 0x00007f8e4a117d2a raise (/lib64/libc.so.6+0x4ad2a)
 llvm#4 0x00007f8e4a1193e4 abort (/lib64/libc.so.6+0x4c3e4)
 llvm#5 0x00007f8e4a10fc69 __assert_fail_base (/lib64/libc.so.6+0x42c69)
 llvm#6 0x00007f8e4a10fcf1 __assert_fail (/lib64/libc.so.6+0x42cf1)
 llvm#7 0x0000000004114367 clang::CodeGen::CodeGenFunction::EmitOMPDepobjDirective(clang::OMPDepobjDirective const&) (/opt/cray/pe/cce/18.0.1/cce-clang/x86_64/bin/clang-18+0x4114367)
 llvm#8 0x00000000040f8fac clang::CodeGen::CodeGenFunction::EmitStmt(clang::Stmt const*, llvm::ArrayRef<clang::Attr const*>) (/opt/cray/pe/cce/18.0.1/cce-clang/x86_64/bin/clang-18+0x40f8fac)
 llvm#9 0x00000000040ff4fb clang::CodeGen::CodeGenFunction::EmitCompoundStmtWithoutScope(clang::CompoundStmt const&, bool, clang::CodeGen::AggValueSlot) (/opt/cray/pe/cce/18.0.1/cce-clang/x86_64/bin/clang-18+0x40ff4fb)
llvm#10 0x00000000041847b2 clang::CodeGen::CodeGenFunction::EmitFunctionBody(clang::Stmt const*) (/opt/cray/pe/cce/18.0.1/cce-clang/x86_64/bin/clang-18+0x41847b2)
llvm#11 0x0000000004199e4a clang::CodeGen::CodeGenFunction::GenerateCode(clang::GlobalDecl, llvm::Function*, clang::CodeGen::CGFunctionInfo const&) (/opt/cray/pe/cce/18.0.1/cce-clang/x86_64/bin/clang-18+0x4199e4a)
llvm#12 0x00000000041f7b9d clang::CodeGen::CodeGenModule::EmitGlobalFunctionDefinition(clang::GlobalDecl, llvm::GlobalValue*) (/opt/cray/pe/cce/18.0.1/cce-clang/x86_64/bin/clang-18+0x41f7b9d)
llvm#13 0x00000000041f16a3 clang::CodeGen::CodeGenModule::EmitGlobalDefinition(clang::GlobalDecl, llvm::GlobalValue*) (/opt/cray/pe/cce/18.0.1/cce-clang/x86_64/bin/clang-18+0x41f16a3)
llvm#14 0x00000000041fd954 clang::CodeGen::CodeGenModule::EmitDeferred() (/opt/cray/pe/cce/18.0.1/cce-clang/x86_64/bin/clang-18+0x41fd954)
llvm#15 0x0000000004200277 clang::CodeGen::CodeGenModule::Release() (/opt/cray/pe/cce/18.0.1/cce-clang/x86_64/bin/clang-18+0x4200277)
llvm#16 0x00000000046b6a49 (anonymous namespace)::CodeGeneratorImpl::HandleTranslationUnit(clang::ASTContext&) ModuleBuilder.cpp:0:0
llvm#17 0x00000000046b4cb6 clang::BackendConsumer::HandleTranslationUnit(clang::ASTContext&) (/opt/cray/pe/cce/18.0.1/cce-clang/x86_64/bin/clang-18+0x46b4cb6)
llvm#18 0x0000000006204d5c clang::ParseAST(clang::Sema&, bool, bool) (/opt/cray/pe/cce/18.0.1/cce-clang/x86_64/bin/clang-18+0x6204d5c)
llvm#19 0x000000000496b278 clang::FrontendAction::Execute() (/opt/cray/pe/cce/18.0.1/cce-clang/x86_64/bin/clang-18+0x496b278)
llvm#20 0x00000000048dd074 clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) (/opt/cray/pe/cce/18.0.1/cce-clang/x86_64/bin/clang-18+0x48dd074)
llvm#21 0x0000000004a38092 clang::ExecuteCompilerInvocation(clang::CompilerInstance*) (/opt/cray/pe/cce/18.0.1/cce-clang/x86_64/bin/clang-18+0x4a38092)
llvm#22 0x0000000000fd4e9c cc1_main(llvm::ArrayRef<char const*>, char const*, void*) (/opt/cray/pe/cce/18.0.1/cce-clang/x86_64/bin/clang-18+0xfd4e9c)
llvm#23 0x0000000000fcca73 ExecuteCC1Tool(llvm::SmallVectorImpl<char const*>&, llvm::ToolContext const&) driver.cpp:0:0
llvm#24 0x0000000000fd140c clang_main(int, char**, llvm::ToolContext const&) (/opt/cray/pe/cce/18.0.1/cce-clang/x86_64/bin/clang-18+0xfd140c)
llvm#25 0x0000000000ee2ef3 main (/opt/cray/pe/cce/18.0.1/cce-clang/x86_64/bin/clang-18+0xee2ef3)
llvm#26 0x00007f8e4a10224c __libc_start_main (/lib64/libc.so.6+0x3524c)
llvm#27 0x0000000000fcaae9 _start /home/abuild/rpmbuild/BUILD/glibc-2.31/csu/../sysdeps/x86_64/start.S:120:0
clang: error: unable to execute command: Aborted
```

---------

Co-authored-by: Chandra Ghale <[email protected]>
seven-mile pushed a commit to seven-mile/clangir that referenced this pull request Nov 13, 2024
…tely from Linux (#115722)

This test fails on
https://lab.llvm.org/staging/#/builders/197/builds/76/steps/18/logs/FAIL__lldb-shell__inline_sites_live_cpp
because of a little difference in the lldb output.

```
# .---command stderr------------
# | C:\buildbot\as-builder-10\lldb-x-aarch64\llvm-project\lldb\test\Shell\SymbolFile\NativePDB\inline_sites_live.cpp:25:11: error: CHECK: expected string not found in input
# | // CHECK: * thread llvm#1, stop reason = breakpoint 1
# |           ^
# | <stdin>:1:1: note: scanning from here
# | (lldb) platform select remote-linux
# | ^
# | <stdin>:28:27: note: possible intended match here
# | * thread llvm#1, name = 'inline_sites_li', stop reason = breakpoint 1.3
# |                           ^
# | 

```
smeenai pushed a commit that referenced this pull request Nov 22, 2024
Add patterns to fold MOV (scalar, predicated) to MOV (imm, pred,
merging) or MOV (imm, pred, zeroing) as appropriate.

This affects the `@llvm.aarch64.sve.dup` intrinsics, which currently
generate MOV (scalar, predicated) instructions even when the
immediate forms are possible. For example:
```
svuint8_t mov_z_b(svbool_t p) {
  return svdup_u8_z(p, 1);
}
```
Currently generates:
```
mov_z_b(__SVBool_t):
        mov     z0.b, #0
        mov     w8, #1
        mov     z0.b, p0/m, w8
        ret
```
Instead of:
```
mov_z_b(__SVBool_t):
        mov     z0.b, p0/z, #1
        ret
```
smeenai pushed a commit that referenced this pull request Nov 22, 2024
…onger cause a crash (#116569)

This PR fixes a bug introduced by #110199, which causes any half float
argument to crash the compiler on MIPS64.

Currently compiling this bit of code with `llc -mtriple=mips64`: 
```
define void @half_args(half %a) nounwind {
entry:
        ret void
}
```

Crashes with the following log:
```
LLVM ERROR: unable to allocate function argument #0
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace.
Stack dump:
0.	Program arguments: llc -mtriple=mips64
1.	Running pass 'Function Pass Manager' on module '<stdin>'.
2.	Running pass 'MIPS DAG->DAG Pattern Instruction Selection' on function '@half_args'
 #0 0x000055a3a4013df8 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/home/davide/Ps2/rps2-tools/prefix/bin/llc+0x32d0df8)
 #1 0x000055a3a401199e llvm::sys::RunSignalHandlers() (/home/davide/Ps2/rps2-tools/prefix/bin/llc+0x32ce99e)
 #2 0x000055a3a40144a8 SignalHandler(int) Signals.cpp:0:0
 #3 0x00007f00bde558c0 __restore_rt libc_sigaction.c:0:0
 #4 0x00007f00bdea462c __pthread_kill_implementation ./nptl/pthread_kill.c:44:76
 #5 0x00007f00bde55822 gsignal ./signal/../sysdeps/posix/raise.c:27:6
 #6 0x00007f00bde3e4af abort ./stdlib/abort.c:81:7
 #7 0x000055a3a3f80e3c llvm::report_fatal_error(llvm::Twine const&, bool) (/home/davide/Ps2/rps2-tools/prefix/bin/llc+0x323de3c)
 #8 0x000055a3a2e20dfa (/home/davide/Ps2/rps2-tools/prefix/bin/llc+0x20dddfa)
 #9 0x000055a3a2a34e20 llvm::MipsTargetLowering::LowerFormalArguments(llvm::SDValue, unsigned int, bool, llvm::SmallVectorImpl<llvm::ISD::InputArg> const&, llvm::SDLoc const&, llvm::SelectionDAG&, llvm::SmallVectorImpl<llvm::SDValue>&) const MipsISelLowering.cpp:0:0
#10 0x000055a3a3d896a9 llvm::SelectionDAGISel::LowerArguments(llvm::Function const&) (/home/davide/Ps2/rps2-tools/prefix/bin/llc+0x30466a9)
#11 0x000055a3a3e0b3ec llvm::SelectionDAGISel::SelectAllBasicBlocks(llvm::Function const&) (/home/davide/Ps2/rps2-tools/prefix/bin/llc+0x30c83ec)
#12 0x000055a3a3e09e21 llvm::SelectionDAGISel::runOnMachineFunction(llvm::MachineFunction&) (/home/davide/Ps2/rps2-tools/prefix/bin/llc+0x30c6e21)
#13 0x000055a3a2aae1ca llvm::MipsDAGToDAGISel::runOnMachineFunction(llvm::MachineFunction&) MipsISelDAGToDAG.cpp:0:0
#14 0x000055a3a3e07706 llvm::SelectionDAGISelLegacy::runOnMachineFunction(llvm::MachineFunction&) (/home/davide/Ps2/rps2-tools/prefix/bin/llc+0x30c4706)
#15 0x000055a3a3051ed6 llvm::MachineFunctionPass::runOnFunction(llvm::Function&) (/home/davide/Ps2/rps2-tools/prefix/bin/llc+0x230eed6)
#16 0x000055a3a35a3ec9 llvm::FPPassManager::runOnFunction(llvm::Function&) (/home/davide/Ps2/rps2-tools/prefix/bin/llc+0x2860ec9)
#17 0x000055a3a35ac3b2 llvm::FPPassManager::runOnModule(llvm::Module&) (/home/davide/Ps2/rps2-tools/prefix/bin/llc+0x28693b2)
#18 0x000055a3a35a499c llvm::legacy::PassManagerImpl::run(llvm::Module&) (/home/davide/Ps2/rps2-tools/prefix/bin/llc+0x286199c)
#19 0x000055a3a262abbb main (/home/davide/Ps2/rps2-tools/prefix/bin/llc+0x18e7bbb)
#20 0x00007f00bde3fc4c __libc_start_call_main ./csu/../sysdeps/nptl/libc_start_call_main.h:74:3
#21 0x00007f00bde3fd05 call_init ./csu/../csu/libc-start.c:128:20
#22 0x00007f00bde3fd05 __libc_start_main@GLIBC_2.2.5 ./csu/../csu/libc-start.c:347:5
#23 0x000055a3a2624921 _start /builddir/glibc-2.39/csu/../sysdeps/x86_64/start.S:117:0
```

This is caused by the fact that after the change, `f16`s are no longer
lowered as `f32`s in calls.

Two possible fixes are available:
- Update calling conventions to properly support passing `f16` as
integers.
- Update `useFPRegsForHalfType()` to return `true` so that `f16` are
still kept in `f32` registers, as before #110199.

This PR implements the first solution to not introduce any more ABI
changes as #110199 already did.

As of what is the correct ABI for halfs, I don't think there is a
correct answer. GCC doesn't support halfs on MIPS, and I couldn't find
any information on old MIPS ABI manuals either.
smeenai pushed a commit that referenced this pull request Nov 23, 2024
…116655)

This is the first part of the effort to make parsing of clause modifiers
more uniform and robust. Currently, when multiple modifiers are allowed,
the parser will expect them to appear in a hard-coded order.
Additionally, modifier properties (such as "ultimate") are checked
separately for each case.

The overall plan is
1. Extract all modifiers into their own top-level classes, and then
equip them with sets of common properties that will allow performing the
property checks generically, without refering to the specific kind of
the modifier.
2. Define a parser (as a separate class) for each modifier.
3. For each clause define a union (std::variant) of all allowable
modifiers, and parse the modifiers as a list of these unions.

The intent is also to isolate parts of the code that could eventually be
auto-generated.

OpenMP modifier overhaul: #1/3
lanza pushed a commit that referenced this pull request Jan 27, 2025
This will be sent by Arm's Guarded Control Stack extension when an
invalid return is executed.

The signal does have an address we could show, but it's the PC at which
the fault occured. The debugger has plenty of ways to show you that
already, so I've left it out.

```
(lldb) c
Process 460 resuming
Process 460 stopped
* thread #1, name = 'test', stop reason = signal SIGSEGV: control protection fault
    frame #0: 0x0000000000400784 test`main at main.c:57:1
   54  	  afunc();
   55  	  printf("return from main\n");
   56  	  return 0;
-> 57  	}
(lldb) dis
<...>
->  0x400784 <+100>: ret
```

The new test case generates the signal by corrupting the link register
then attempting to return. This will work whether we manually enable GCS
or the C library does it for us.

(in the former case you could just return from main and it would fault)
lanza pushed a commit that referenced this pull request Jan 27, 2025
…" (#123877)

Reverts llvm/llvm-project#122811 due to buildbot breakage e.g.,
https://lab.llvm.org/buildbot/#/builders/52/builds/5421/steps/11/logs/stdio

ASan output from local re-run:
```
==2780289==ERROR: AddressSanitizer: use-after-poison on address 0x7e0b87e28d28 at pc 0x55a979a99e7e bp 0x7ffe4b18f0b0 sp 0x7ffe4b18f0a8
READ of size 1 at 0x7e0b87e28d28 thread T0
    #0 0x55a979a99e7d in getStorageClass /usr/local/google/home/thurston/buildbot_repro/llvm-project/llvm/include/llvm/Object/COFF.h:344
    #1 0x55a979a99e7d in isSectionDefinition /usr/local/google/home/thurston/buildbot_repro/llvm-project/llvm/include/llvm/Object/COFF.h:429:9
    #2 0x55a979a99e7d in getSymbols /usr/local/google/home/thurston/buildbot_repro/llvm-project/lld/COFF/LLDMapFile.cpp:54:42
    #3 0x55a979a99e7d in lld::coff::writeLLDMapFile(lld::coff::COFFLinkerContext const&) /usr/local/google/home/thurston/buildbot_repro/llvm-project/lld/COFF/LLDMapFile.cpp:103:40
    #4 0x55a979a16879 in (anonymous namespace)::Writer::run() /usr/local/google/home/thurston/buildbot_repro/llvm-project/lld/COFF/Writer.cpp:810:3
    #5 0x55a979a00aac in lld::coff::writeResult(lld::coff::COFFLinkerContext&) /usr/local/google/home/thurston/buildbot_repro/llvm-project/lld/COFF/Writer.cpp:354:15
    #6 0x55a97985f7ed in lld::coff::LinkerDriver::linkerMain(llvm::ArrayRef<char const*>) /usr/local/google/home/thurston/buildbot_repro/llvm-project/lld/COFF/Driver.cpp:2826:3
    #7 0x55a97984cdd3 in lld::coff::link(llvm::ArrayRef<char const*>, llvm::raw_ostream&, llvm::raw_ostream&, bool, bool) /usr/local/google/home/thurston/buildbot_repro/llvm-project/lld/COFF/Driver.cpp:97:15
    #8 0x55a9797f9793 in lld::unsafeLldMain(llvm::ArrayRef<char const*>, llvm::raw_ostream&, llvm::raw_ostream&, llvm::ArrayRef<lld::DriverDef>, bool) /usr/local/google/home/thurston/buildbot_repro/llvm-project/lld/Common/DriverDispatcher.cpp:163:12
    #9 0x55a9797fa3b6 in operator() /usr/local/google/home/thurston/buildbot_repro/llvm-project/lld/Common/DriverDispatcher.cpp:188:15
    #10 0x55a9797fa3b6 in void llvm::function_ref<void ()>::callback_fn<lld::lldMain(llvm::ArrayRef<char const*>, llvm::raw_ostream&, llvm::raw_ostream&, llvm::ArrayRef<lld::DriverDef>)::$_0>(long) /usr/local/google/home/thurston/buildbot_repro/llvm-project/llvm/include/llvm/ADT/STLFunctionalExtras.h:46:12
    #11 0x55a97966cb93 in operator() /usr/local/google/home/thurston/buildbot_repro/llvm-project/llvm/include/llvm/ADT/STLFunctionalExtras.h:69:12
    #12 0x55a97966cb93 in llvm::CrashRecoveryContext::RunSafely(llvm::function_ref<void ()>) /usr/local/google/home/thurston/buildbot_repro/llvm-project/llvm/lib/Support/CrashRecoveryContext.cpp:426:3
    #13 0x55a9797f9dc3 in lld::lldMain(llvm::ArrayRef<char const*>, llvm::raw_ostream&, llvm::raw_ostream&, llvm::ArrayRef<lld::DriverDef>) /usr/local/google/home/thurston/buildbot_repro/llvm-project/lld/Common/DriverDispatcher.cpp:187:14
    #14 0x55a979627512 in lld_main(int, char**, llvm::ToolContext const&) /usr/local/google/home/thurston/buildbot_repro/llvm-project/lld/tools/lld/lld.cpp:103:14
    #15 0x55a979628731 in main /usr/local/google/home/thurston/buildbot_repro/llvm_build_asan/tools/lld/tools/lld/lld-driver.cpp:17:10
    #16 0x7ffb8b202c89 in __libc_start_call_main csu/../sysdeps/nptl/libc_start_call_main.h:58:16
    #17 0x7ffb8b202d44 in __libc_start_main csu/../csu/libc-start.c:360:3
    #18 0x55a97953ef60 in _start (/usr/local/google/home/thurston/buildbot_repro/llvm_build_asan/bin/lld+0x8fd1f60)
```
lanza pushed a commit that referenced this pull request Jan 27, 2025
Prevents avoidable memory leaks.

Looks like exchange added in aa1333a
didn't take "continue" into account.

```
==llc==2150782==ERROR: LeakSanitizer: detected memory leaks
Direct leak of 10 byte(s) in 1 object(s) allocated from:
    #0 0x5f1b0f9ac14a in strdup llvm-project/compiler-rt/lib/asan/asan_interceptors.cpp:593:3
    #1 0x5f1b1768428d in FileToRemoveList llvm-project/llvm/lib/Support/Unix/Signals.inc:105:55
```
bcardosolopes pushed a commit that referenced this pull request Feb 5, 2025
This PR fixes two run time bugs in the calling convention pass. These
bugs were found with `csmith`.

Case #1.  Return value from a function. 
Before this PR the returned value were stored in a bit casted memory
location.
But for the next example it's not safe: the size of a memory slot is
less than the size of return value. And the store operation cause a
segfault!
```
#pragma pack(push)
#pragma pack(1)
 typedef struct {
    int f0 : 18;
    int f1 : 31;
    int f2 : 5;
    int f3 : 29;
    int f4 : 24;
 } PackedS;
#pragma pack(pop)
```
CIR type for this struct is `!ty_PackedS1_ = !cir.struct<struct
"PackedS1" {!cir.array<!u8i x 14>}>`, i.e. it occupies 14 bytes.
Before this PR the next code 
```
PackedS foo(void) {
     PackedS s;
     return s;
}

 void check(void) {     
     PackedS y = foo();    
}
```
produced the next CIR:
```
  %0 = cir.alloca !ty_PackedS1_, !cir.ptr<!ty_PackedS1_>, ["y", init] {alignment = 1 : i64}
  %1 = cir.call @foo() : () -> !cir.array<!u64i x 2> 
  %2 = cir.cast(bitcast, %0 : !cir.ptr<!ty_PackedS1_>), !cir.ptr<!cir.array<!u64i x 2>>
  cir.store %1, %2 : !cir.array<!u64i x 2>, !cir.ptr<!cir.array<!u64i x 2>>
```
As one cat see, `%1` is an array of two 64-bit integers and the memory
was allocated for 14 bytes only (size of struct). Hence the segfault!
This PR fixes such cases and now we have a coercion through memory,
which is even with the OG.


Case #2.  Passing an argument from a pointer deref.
Previously for the struct types passed by value we tried to find alloca
instruction in order to use it as a source for memcpy operation. But if
we have pointer dereference, (in other words if we have a `<!cir.ptr <
!cir.ptr ... > >` as alloca result) we don't need to search for the
address of the location where this pointer stored - instead we're
interested in the pointer itself. And it's a general approach - instead
of trying to find an alloca instruction we need to find a first pointer
on the way - that will be an address we meed to use for the memcpy
source.

I combined these two cases into a single PR since there are only few
changes actually. But I can split in two if you'd prefer
lanza pushed a commit that referenced this pull request Mar 18, 2025
…no override (#893)

As title. 
The test case used is abort(), but it is from the real code. 
Notice: Since CIR implementation for NoReturn Call is pending to
implement, the generated llvm code is like:
`define dso_local void @test() #1  {
  call void @abort(), !dbg !8
  ret void
}`
which is not right, right code should be like, 
`
`define dso_local void @test() #1  {
  call void @abort(), !dbg !8
  unreachable
}`
`
Still send this PR as Noreturn implementation is a separate issue.
lanza pushed a commit that referenced this pull request Mar 18, 2025
This PR fixes two run time bugs in the calling convention pass. These
bugs were found with `csmith`.

Case #1.  Return value from a function.
Before this PR the returned value were stored in a bit casted memory
location.
But for the next example it's not safe: the size of a memory slot is
less than the size of return value. And the store operation cause a
segfault!
```
#pragma pack(push)
#pragma pack(1)
 typedef struct {
    int f0 : 18;
    int f1 : 31;
    int f2 : 5;
    int f3 : 29;
    int f4 : 24;
 } PackedS;
#pragma pack(pop)
```
CIR type for this struct is `!ty_PackedS1_ = !cir.struct<struct
"PackedS1" {!cir.array<!u8i x 14>}>`, i.e. it occupies 14 bytes.
Before this PR the next code
```
PackedS foo(void) {
     PackedS s;
     return s;
}

 void check(void) {
     PackedS y = foo();
}
```
produced the next CIR:
```
  %0 = cir.alloca !ty_PackedS1_, !cir.ptr<!ty_PackedS1_>, ["y", init] {alignment = 1 : i64}
  %1 = cir.call @foo() : () -> !cir.array<!u64i x 2>
  %2 = cir.cast(bitcast, %0 : !cir.ptr<!ty_PackedS1_>), !cir.ptr<!cir.array<!u64i x 2>>
  cir.store %1, %2 : !cir.array<!u64i x 2>, !cir.ptr<!cir.array<!u64i x 2>>
```
As one cat see, `%1` is an array of two 64-bit integers and the memory
was allocated for 14 bytes only (size of struct). Hence the segfault!
This PR fixes such cases and now we have a coercion through memory,
which is even with the OG.

Case #2.  Passing an argument from a pointer deref.
Previously for the struct types passed by value we tried to find alloca
instruction in order to use it as a source for memcpy operation. But if
we have pointer dereference, (in other words if we have a `<!cir.ptr <
!cir.ptr ... > >` as alloca result) we don't need to search for the
address of the location where this pointer stored - instead we're
interested in the pointer itself. And it's a general approach - instead
of trying to find an alloca instruction we need to find a first pointer
on the way - that will be an address we meed to use for the memcpy
source.

I combined these two cases into a single PR since there are only few
changes actually. But I can split in two if you'd prefer
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2 participants