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Merged
merged 2 commits into from
Jan 31, 2022
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b-s-a
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@b-s-a b-s-a commented Dec 2, 2019

24-bit eZ80 registers now defined like in RISCV source code.
Change eliminates register name duplication.

@b-s-a b-s-a force-pushed the z80-regs-ref branch 2 times, most recently from 7c9bc64 to 045ae6a Compare December 2, 2019 14:08
@mateoconlechuga
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This is wrong: https://github.com/jacobly0/llvm-project/pull/6/files#diff-12eb8967dc2dd2037ac725d8dd933a6cR89

Also I'm not sure what purpose this change serves.

@b-s-a
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b-s-a commented Dec 5, 2019

This change fixes register name conflict which is appears when you try to create asm matcher.

@jacobly0 jacobly0 force-pushed the z80 branch 4 times, most recently from 6696e2f to 7681d6e Compare January 2, 2020 16:13
@jacobly0 jacobly0 force-pushed the z80 branch 3 times, most recently from b30e6c8 to 69db7e4 Compare January 20, 2020 00:10
jacobly0 pushed a commit that referenced this pull request Jan 20, 2020
…t binding

This fixes a failing testcase on Fedora 30 x86_64 (regression Fedora 29->30):

PASS:
./bin/lldb ./lldb-test-build.noindex/functionalities/unwind/noreturn/TestNoreturnUnwind.test_dwarf/a.out -o 'settings set symbols.enable-external-lookup false' -o r -o bt -o quit
  * frame #0: 0x00007ffff7aa6e75 libc.so.6`__GI_raise + 325
    frame #1: 0x00007ffff7a91895 libc.so.6`__GI_abort + 295
    frame #2: 0x0000000000401140 a.out`func_c at main.c:12:2
    frame #3: 0x000000000040113a a.out`func_b at main.c:18:2
    frame #4: 0x0000000000401134 a.out`func_a at main.c:26:2
    frame #5: 0x000000000040112e a.out`main(argc=<unavailable>, argv=<unavailable>) at main.c:32:2
    frame #6: 0x00007ffff7a92f33 libc.so.6`__libc_start_main + 243
    frame #7: 0x000000000040106e a.out`_start + 46

vs.

FAIL - unrecognized abort() function:
./bin/lldb ./lldb-test-build.noindex/functionalities/unwind/noreturn/TestNoreturnUnwind.test_dwarf/a.out -o 'settings set symbols.enable-external-lookup false' -o r -o bt -o quit
  * frame #0: 0x00007ffff7aa6e75 libc.so.6`.annobin_raise.c + 325
    frame #1: 0x00007ffff7a91895 libc.so.6`.annobin_loadmsgcat.c_end.unlikely + 295
    frame #2: 0x0000000000401140 a.out`func_c at main.c:12:2
    frame #3: 0x000000000040113a a.out`func_b at main.c:18:2
    frame #4: 0x0000000000401134 a.out`func_a at main.c:26:2
    frame #5: 0x000000000040112e a.out`main(argc=<unavailable>, argv=<unavailable>) at main.c:32:2
    frame #6: 0x00007ffff7a92f33 libc.so.6`.annobin_libc_start.c + 243
    frame #7: 0x000000000040106e a.out`.annobin_init.c.hot + 46

The extra ELF symbols are there due to Annobin (I did not investigate why this
problem happened specifically since F-30 and not since F-28).

It is due to:

Symbol table '.dynsym' contains 2361 entries:
Valu e          Size Type   Bind   Vis     Name
0000000000022769   5 FUNC   LOCAL  DEFAULT _nl_load_domain.cold
000000000002276e   0 NOTYPE LOCAL  HIDDEN  .annobin_abort.c.unlikely
...
000000000002276e   0 NOTYPE LOCAL  HIDDEN  .annobin_loadmsgcat.c_end.unlikely
...
000000000002276e   0 NOTYPE LOCAL  HIDDEN  .annobin_textdomain.c_end.unlikely
000000000002276e 548 FUNC   GLOBAL DEFAULT abort
000000000002276e 548 FUNC   GLOBAL DEFAULT abort@@GLIBC_2.2.5
000000000002276e 548 FUNC   LOCAL  DEFAULT __GI_abort
0000000000022992   0 NOTYPE LOCAL  HIDDEN  .annobin_abort.c_end.unlikely

GDB has some more complicated preferences between overlapping and/or sharing
address symbols, I have made here so far the most simple fix for this case.

Differential revision: https://reviews.llvm.org/D63540
jacobly0 pushed a commit that referenced this pull request Jan 20, 2020
The test is currently failing on some systems with ASAN enabled due to:
```
==22898==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x603000003da4 at pc 0x00010951c33d bp 0x7ffee6709e00 sp 0x7ffee67095c0
READ of size 5 at 0x603000003da4 thread T0
    #0 0x10951c33c in wrap_memmove+0x16c (libclang_rt.asan_osx_dynamic.dylib:x86_64+0x1833c)
    #1 0x7fff4a327f57 in CFDataReplaceBytes+0x1ba (CoreFoundation:x86_64+0x13f57)
    #2 0x7fff4a415a44 in __CFDataInit+0x2db (CoreFoundation:x86_64+0x101a44)
    #3 0x1094f8490 in main main.m:424
    #4 0x7fff77482084 in start+0x0 (libdyld.dylib:x86_64+0x17084)
0x603000003da4 is located 0 bytes to the right of 20-byte region [0x603000003d90,0x603000003da4)
allocated by thread T0 here:
    #0 0x109547c02 in wrap_calloc+0xa2 (libclang_rt.asan_osx_dynamic.dylib:x86_64+0x43c02)
    #1 0x7fff763ad3ef in class_createInstance+0x52 (libobjc.A.dylib:x86_64+0x73ef)
    #2 0x7fff4c6b2d73 in NSAllocateObject+0x12 (Foundation:x86_64+0x1d73)
    #3 0x7fff4c6b5e5f in -[_NSPlaceholderData initWithBytes:length:copy:deallocator:]+0x40 (Foundation:x86_64+0x4e5f)
    #4 0x7fff4c6d4cf1 in -[NSData(NSData) initWithBytes:length:]+0x24 (Foundation:x86_64+0x23cf1)
    #5 0x1094f8245 in main main.m:404
    #6 0x7fff77482084 in start+0x0 (libdyld.dylib:x86_64+0x17084)
```

The reason is that we create a string "HELLO" but get the size wrong (it's 5 bytes instead
of 4). Later on we read the buffer and pretend it is 5 bytes long, causing an OOB read
which ASAN detects.

In general this test probably needs some cleanup as it produces on macOS 10.15 around
100 compiler warnings which isn't great, but let's first get the bot green.
jacobly0 pushed a commit that referenced this pull request Jan 26, 2020
This reverts commit e57a9ab.

Parser/cxx2a-placeholder-type-constraint.cpp has MSan failures.

Present at 7b81c3f:
http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-bootstrap-msan/builds/17133/steps/check-clang%20msan/logs/stdio
not present at eaa594f:
http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-bootstrap-msan/builds/17132/steps/check-clang%20msan/logs/stdio

Stack trace:
```
==57032==WARNING: MemorySanitizer: use-of-uninitialized-value
    #0 0xccfe016 in clang::AutoTypeLoc::getLocalSourceRange() const /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/include/clang/AST/TypeLoc.h:2036:19
    #1 0xcc56758 in CheckDeducedPlaceholderConstraints(clang::Sema&, clang::AutoType const&, clang::AutoTypeLoc, clang::QualType) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Sema/SemaTemplateDeduction.cpp:4505:56
    #2 0xcc550ce in clang::Sema::DeduceAutoType(clang::TypeLoc, clang::Expr*&, clang::QualType&, llvm::Optional<unsigned int>, bool) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Sema/SemaTemplateDeduction.cpp:4707:11
    #3 0xcc52407 in clang::Sema::DeduceAutoType(clang::TypeSourceInfo*, clang::Expr*&, clang::QualType&, llvm::Optional<unsigned int>, bool) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Sema/SemaTemplateDeduction.cpp:4457:10
    #4 0xba38332 in clang::Sema::deduceVarTypeFromInitializer(clang::VarDecl*, clang::DeclarationName, clang::QualType, clang::TypeSourceInfo*, clang::SourceRange, bool, clang::Expr*) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Sema/SemaDecl.cpp:11351:7
    #5 0xba3a8a9 in clang::Sema::DeduceVariableDeclarationType(clang::VarDecl*, bool, clang::Expr*) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Sema/SemaDecl.cpp:11385:26
    #6 0xba3c520 in clang::Sema::AddInitializerToDecl(clang::Decl*, clang::Expr*, bool) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Sema/SemaDecl.cpp:11725:9
    #7 0xb39c498 in clang::Parser::ParseDeclarationAfterDeclaratorAndAttributes(clang::Declarator&, clang::Parser::ParsedTemplateInfo const&, clang::Parser::ForRangeInit*) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Parse/ParseDecl.cpp:2399:17
    #8 0xb394d80 in clang::Parser::ParseDeclGroup(clang::ParsingDeclSpec&, clang::DeclaratorContext, clang::SourceLocation*, clang::Parser::ForRangeInit*) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Parse/ParseDecl.cpp:2128:21
    #9 0xb383bbf in clang::Parser::ParseSimpleDeclaration(clang::DeclaratorContext, clang::SourceLocation&, clang::Parser::ParsedAttributesWithRange&, bool, clang::Parser::ForRangeInit*, clang::SourceLocation*) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Parse/ParseDecl.cpp:1848:10
    #10 0xb383129 in clang::Parser::ParseDeclaration(clang::DeclaratorContext, clang::SourceLocation&, clang::Parser::ParsedAttributesWithRange&, clang::SourceLocation*) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/llvm/include/llvm/ADT/PointerUnion.h
    #11 0xb53a388 in clang::Parser::ParseStatementOrDeclarationAfterAttributes(llvm::SmallVector<clang::Stmt*, 32u>&, clang::Parser::ParsedStmtContext, clang::SourceLocation*, clang::Parser::ParsedAttributesWithRange&) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Parse/ParseStmt.cpp:221:13
    #12 0xb539309 in clang::Parser::ParseStatementOrDeclaration(llvm::SmallVector<clang::Stmt*, 32u>&, clang::Parser::ParsedStmtContext, clang::SourceLocation*) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Parse/ParseStmt.cpp:106:20
    #13 0xb55610e in clang::Parser::ParseCompoundStatementBody(bool) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Parse/ParseStmt.cpp:1079:11
    #14 0xb559529 in clang::Parser::ParseFunctionStatementBody(clang::Decl*, clang::Parser::ParseScope&) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Parse/ParseStmt.cpp:2204:21
    #15 0xb33c13e in clang::Parser::ParseFunctionDefinition(clang::ParsingDeclarator&, clang::Parser::ParsedTemplateInfo const&, clang::Parser::LateParsedAttrList*) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Parse/Parser.cpp:1339:10
    #16 0xb394703 in clang::Parser::ParseDeclGroup(clang::ParsingDeclSpec&, clang::DeclaratorContext, clang::SourceLocation*, clang::Parser::ForRangeInit*) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Parse/ParseDecl.cpp:2068:11
    #17 0xb338e52 in clang::Parser::ParseDeclOrFunctionDefInternal(clang::Parser::ParsedAttributesWithRange&, clang::ParsingDeclSpec&, clang::AccessSpecifier) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Parse/Parser.cpp:1099:10
    #18 0xb337674 in clang::Parser::ParseDeclarationOrFunctionDefinition(clang::Parser::ParsedAttributesWithRange&, clang::ParsingDeclSpec*, clang::AccessSpecifier) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Parse/Parser.cpp:1115:12
    #19 0xb334a96 in clang::Parser::ParseExternalDeclaration(clang::Parser::ParsedAttributesWithRange&, clang::ParsingDeclSpec*) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Parse/Parser.cpp:935:12
    #20 0xb32f12a in clang::Parser::ParseTopLevelDecl(clang::OpaquePtr<clang::DeclGroupRef>&, bool) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Parse/Parser.cpp:686:12
    #21 0xb31e193 in clang::ParseAST(clang::Sema&, bool, bool) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Parse/ParseAST.cpp:158:20
    #22 0x80263f0 in clang::FrontendAction::Execute() /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Frontend/FrontendAction.cpp:936:8
    #23 0x7f2a257 in clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Frontend/CompilerInstance.cpp:965:33
    #24 0x8288bef in clang::ExecuteCompilerInvocation(clang::CompilerInstance*) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/FrontendTool/ExecuteCompilerInvocation.cpp:290:25
    #25 0xad44c2 in cc1_main(llvm::ArrayRef<char const*>, char const*, void*) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/tools/driver/cc1_main.cpp:239:15
    #26 0xacd76a in ExecuteCC1Tool(llvm::ArrayRef<char const*>) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/tools/driver/driver.cpp:325:12
    #27 0xacc9fd in main /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/tools/driver/driver.cpp:398:12
    #28 0x7f7d82cdb2e0 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x202e0)
    #29 0xa4dde9 in _start (/b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm_build_msan/bin/clang-11+0xa4dde9)
```
@jacobly0 jacobly0 force-pushed the z80 branch 3 times, most recently from 14276c6 to 132d81e Compare January 27, 2020 00:44
jacobly0 pushed a commit that referenced this pull request Feb 9, 2020
Summary:
Applying this cleanup:

    -      MIRBuilder.buildInstr(TargetOpcode::G_ASHR)
    -        .addDef(Shifted)
    -        .addUse(Res)
    -        .addUse(ShiftAmt);
    +      MIRBuilder.buildAShr(Shifted, Res, ShiftAmt);

caused an assertion failure here:

    llc: /home/jayfoad2/git/llvm-project/llvm/lib/CodeGen/MachineRegisterInfo.cpp:404: llvm::MachineInstr *llvm::MachineRegisterInfo::getVRegDef(unsigned int) const: Assertion `(I.atEnd() || std::next(I) == def_instr_end()) && "getVRegDef assumes a single definition or no definition"' failed.

    #4  0x00000000050a6d96 in llvm::MachineRegisterInfo::getVRegDef (this=0x74606a0, Reg=2147483650) at /home/jayfoad2/git/llvm-project/llvm/lib/CodeGen/MachineRegisterInfo.cpp:403
    #5  0x00000000066148f6 in llvm::getConstantVRegValWithLookThrough (VReg=2147483650, MRI=..., LookThroughInstrs=false, HandleFConstant=true) at /home/jayfoad2/git/llvm-project/llvm/lib/CodeGen/GlobalISel/Utils.cpp:244
    #6  0x00000000066147da in llvm::getConstantVRegVal (VReg=2147483650, MRI=...) at /home/jayfoad2/git/llvm-project/llvm/lib/CodeGen/GlobalISel/Utils.cpp:210
    #7  0x0000000006615367 in llvm::ConstantFoldBinOp (Opcode=101, Op1=2147483650, Op2=2147483656, MRI=...) at /home/jayfoad2/git/llvm-project/llvm/lib/CodeGen/GlobalISel/Utils.cpp:341
    #8  0x000000000657eee0 in llvm::CSEMIRBuilder::buildInstr (this=0x7465010, Opc=101, DstOps=..., SrcOps=..., Flag=...) at /home/jayfoad2/git/llvm-project/llvm/lib/CodeGen/GlobalISel/CSEMIRBuilder.cpp:160
    #9  0x0000000003645958 in llvm::MachineIRBuilder::buildAShr (this=0x7465010, Dst=..., Src0=..., Src1=..., Flags=...) at /home/jayfoad2/git/llvm-project/llvm/include/llvm/CodeGen/GlobalISel/MachineIRBuilder.h:1298
    #10 0x00000000065c35b1 in llvm::LegalizerHelper::lower (this=0x7fffffffb5f8, MI=..., TypeIdx=0, Ty=...) at /home/jayfoad2/git/llvm-project/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp:2020

because at this point there are two instructions defining Res: the
original G_SMULO/G_UMULO and the new G_MUL that we built. The fix is
to modify the original mul in place, so that there is only ever one
definition of Res.

Reviewers: arsenm, aditya_nandakumar

Subscribers: wdng, rovka, hiraditya, volkan, Petar.Avramovic, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D72842
@jacobly0 jacobly0 force-pushed the z80 branch 6 times, most recently from e5934f7 to 5b472dc Compare March 7, 2020 23:41
@jacobly0 jacobly0 force-pushed the z80 branch 2 times, most recently from 64d4b69 to fe2ea70 Compare March 10, 2020 06:45
b-s-a and others added 2 commits January 31, 2022 04:08
24-bit eZ80 registers now defined like in RISCV source code.
Change eliminates register name duplication.
@jacobly0
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Thanks!

@jacobly0 jacobly0 closed this Jan 31, 2022
@jacobly0 jacobly0 reopened this Jan 31, 2022
@jacobly0 jacobly0 merged this pull request into jacobly0:z80 Jan 31, 2022
jacobly0 added a commit that referenced this pull request Jan 31, 2022
jacobly0 pushed a commit that referenced this pull request Feb 8, 2022
We experienced some deadlocks when we used multiple threads for logging
using `scan-builds` intercept-build tool when we used multiple threads by
e.g. logging `make -j16`

```
(gdb) bt
#0  0x00007f2bb3aff110 in __lll_lock_wait () from /lib/x86_64-linux-gnu/libpthread.so.0
#1  0x00007f2bb3af70a3 in pthread_mutex_lock () from /lib/x86_64-linux-gnu/libpthread.so.0
#2  0x00007f2bb3d152e4 in ?? ()
#3  0x00007ffcc5f0cc80 in ?? ()
#4  0x00007f2bb3d2bf5b in ?? () from /lib64/ld-linux-x86-64.so.2
#5  0x00007f2bb3b5da27 in ?? () from /lib/x86_64-linux-gnu/libc.so.6
#6  0x00007f2bb3b5dbe0 in exit () from /lib/x86_64-linux-gnu/libc.so.6
#7  0x00007f2bb3d144ee in ?? ()
#8  0x746e692f706d742f in ?? ()
#9  0x692d747065637265 in ?? ()
#10 0x2f653631326b3034 in ?? ()
#11 0x646d632e35353532 in ?? ()
#12 0x0000000000000000 in ?? ()
```

I think the gcc's exit call caused the injected `libear.so` to be unloaded
by the `ld`, which in turn called the `void on_unload() __attribute__((destructor))`.
That tried to acquire an already locked mutex which was left locked in the
`bear_report_call()` call, that probably encountered some error and
returned early when it forgot to unlock the mutex.

All of these are speculation since from the backtrace I could not verify
if frames 2 and 3 are in fact corresponding to the `libear.so` module.
But I think it's a fairly safe bet.

So, hereby I'm releasing the held mutex on *all paths*, even if some failure
happens.

PS: I would use lock_guards, but it's C.

Reviewed-by: NoQ

Differential Revision: https://reviews.llvm.org/D118439
nebulatgs pushed a commit to nebulatgs/llvm-project that referenced this pull request Mar 23, 2022
We experienced some deadlocks when we used multiple threads for logging
using `scan-builds` intercept-build tool when we used multiple threads by
e.g. logging `make -j16`

```
(gdb) bt
#0  0x00007f2bb3aff110 in __lll_lock_wait () from /lib/x86_64-linux-gnu/libpthread.so.0
jacobly0#1  0x00007f2bb3af70a3 in pthread_mutex_lock () from /lib/x86_64-linux-gnu/libpthread.so.0
jacobly0#2  0x00007f2bb3d152e4 in ?? ()
jacobly0#3  0x00007ffcc5f0cc80 in ?? ()
jacobly0#4  0x00007f2bb3d2bf5b in ?? () from /lib64/ld-linux-x86-64.so.2
jacobly0#5  0x00007f2bb3b5da27 in ?? () from /lib/x86_64-linux-gnu/libc.so.6
jacobly0#6  0x00007f2bb3b5dbe0 in exit () from /lib/x86_64-linux-gnu/libc.so.6
jacobly0#7  0x00007f2bb3d144ee in ?? ()
jacobly0#8  0x746e692f706d742f in ?? ()
jacobly0#9  0x692d747065637265 in ?? ()
jacobly0#10 0x2f653631326b3034 in ?? ()
jacobly0#11 0x646d632e35353532 in ?? ()
jacobly0#12 0x0000000000000000 in ?? ()
```

I think the gcc's exit call caused the injected `libear.so` to be unloaded
by the `ld`, which in turn called the `void on_unload() __attribute__((destructor))`.
That tried to acquire an already locked mutex which was left locked in the
`bear_report_call()` call, that probably encountered some error and
returned early when it forgot to unlock the mutex.

All of these are speculation since from the backtrace I could not verify
if frames 2 and 3 are in fact corresponding to the `libear.so` module.
But I think it's a fairly safe bet.

So, hereby I'm releasing the held mutex on *all paths*, even if some failure
happens.

PS: I would use lock_guards, but it's C.

Reviewed-by: NoQ

Differential Revision: https://reviews.llvm.org/D118439

(cherry picked from commit d919d02)
jacobly0 pushed a commit that referenced this pull request Jun 4, 2022
This reverts commit c274b6e.

The x86_64 debian bot got a failure with this patch,
https://lab.llvm.org/buildbot#builders/68/builds/33078
where
SymbolFile/DWARF/x86/DW_TAG_variable-DW_AT_decl_file-DW_AT_abstract_origin-crosscu1.s
is crashing here -

 #2 0x0000000000425a9f SignalHandler(int) Signals.cpp:0:0
 #3 0x00007f57160e9140 __restore_rt (/lib/x86_64-linux-gnu/libpthread.so.0+0x14140)
 #4 0x00007f570d911e43 lldb_private::SourceManager::GetFile(lldb_private::FileSpec const&) crtstuff.c:0:0
 #5 0x00007f570d914270 lldb_private::SourceManager::DisplaySourceLinesWithLineNumbers(lldb_private::FileSpec const&, unsigned int, unsigned int, unsigned int, unsigned int, char const*, lldb_private::Stream*, lldb_private::SymbolContextList const*) crtstuff.c:0:0
 #6 0x00007f570da662c8 lldb_private::StackFrame::GetStatus(lldb_private::Stream&, bool, bool, bool, char const*) crtstuff.c:0:0

I don't get a failure here my mac, I'll review this method more
closely tomorrow.
jacobly0 pushed a commit that referenced this pull request Aug 22, 2024

Verified

This commit was created on GitHub.com and signed with GitHub’s verified signature.
…104523)

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
```
jacobly0 pushed a commit that referenced this pull request Sep 6, 2024

Verified

This commit was created on GitHub.com and signed with GitHub’s verified signature.
Static destructor can race with calls to notify and trigger tsan
warning.

```
WARNING: ThreadSanitizer: data race (pid=5787)
  Write of size 1 at 0x55bec9df8de8 by thread T23:
    #0 pthread_mutex_destroy [third_party/llvm/llvm-project/compiler-rt/lib/tsan/rtl/tsan_interceptors_posix.cpp:1344](third_party/llvm/llvm-project/compiler-rt/lib/tsan/rtl/tsan_interceptors_posix.cpp?l=1344&cl=669089572):3 (be1eb158bb70fc9cf7be2db70407e512890e5c6e20720cd88c69d7d9c26ea531_0200d5f71908+0x1b12affb) (BuildId: ff25ace8b17d9863348bb1759c47246c)
    #1 __libcpp_recursive_mutex_destroy [third_party/crosstool/v18/stable/src/libcxx/include/__thread/support/pthread.h:91](third_party/crosstool/v18/stable/src/libcxx/include/__thread/support/pthread.h?l=91&cl=669089572):10 (be1eb158bb70fc9cf7be2db70407e512890e5c6e20720cd88c69d7d9c26ea531_0200d5f71908+0x4523d4e9) (BuildId: ff25ace8b17d9863348bb1759c47246c)
    #2 std::__tsan::recursive_mutex::~recursive_mutex() [third_party/crosstool/v18/stable/src/libcxx/src/mutex.cpp:52](third_party/crosstool/v18/stable/src/libcxx/src/mutex.cpp?l=52&cl=669089572):11 (be1eb158bb70fc9cf7be2db70407e512890e5c6e20720cd88c69d7d9c26ea531_0200d5f71908+0x4523d4e9)
    #3 ~SmartMutex [third_party/llvm/llvm-project/llvm/include/llvm/Support/Mutex.h:28](third_party/llvm/llvm-project/llvm/include/llvm/Support/Mutex.h?l=28&cl=669089572):11 (be1eb158bb70fc9cf7be2db70407e512890e5c6e20720cd88c69d7d9c26ea531_0200d5f71908+0x2bcaedfe) (BuildId: ff25ace8b17d9863348bb1759c47246c)
    #4 (anonymous namespace)::PerfJITEventListener::~PerfJITEventListener() [third_party/llvm/llvm-project/llvm/lib/ExecutionEngine/PerfJITEvents/PerfJITEventListener.cpp:65](third_party/llvm/llvm-project/llvm/lib/ExecutionEngine/PerfJITEvents/PerfJITEventListener.cpp?l=65&cl=669089572):3 (be1eb158bb70fc9cf7be2db70407e512890e5c6e20720cd88c69d7d9c26ea531_0200d5f71908+0x2bcaedfe)
    #5 cxa_at_exit_callback_installed_at(void*) [third_party/llvm/llvm-project/compiler-rt/lib/tsan/rtl/tsan_interceptors_posix.cpp:437](third_party/llvm/llvm-project/compiler-rt/lib/tsan/rtl/tsan_interceptors_posix.cpp?l=437&cl=669089572):3 (be1eb158bb70fc9cf7be2db70407e512890e5c6e20720cd88c69d7d9c26ea531_0200d5f71908+0x1b172cb9) (BuildId: ff25ace8b17d9863348bb1759c47246c)
    #6 llvm::JITEventListener::createPerfJITEventListener() [third_party/llvm/llvm-project/llvm/lib/ExecutionEngine/PerfJITEvents/PerfJITEventListener.cpp:496](third_party/llvm/llvm-project/llvm/lib/ExecutionEngine/PerfJITEvents/PerfJITEventListener.cpp?l=496&cl=669089572):3 (be1eb158bb70fc9cf7be2db70407e512890e5c6e20720cd88c69d7d9c26ea531_0200d5f71908+0x2bcad8f5) (BuildId: ff25ace8b17d9863348bb1759c47246c)
```
```
Previous atomic read of size 1 at 0x55bec9df8de8 by thread T192 (mutexes: write M0, write M1):
    #0 pthread_mutex_unlock [third_party/llvm/llvm-project/compiler-rt/lib/tsan/rtl/tsan_interceptors_posix.cpp:1387](third_party/llvm/llvm-project/compiler-rt/lib/tsan/rtl/tsan_interceptors_posix.cpp?l=1387&cl=669089572):3 (be1eb158bb70fc9cf7be2db70407e512890e5c6e20720cd88c69d7d9c26ea531_0200d5f71908+0x1b12b6bb) (BuildId: ff25ace8b17d9863348bb1759c47246c)
    #1 __libcpp_recursive_mutex_unlock [third_party/crosstool/v18/stable/src/libcxx/include/__thread/support/pthread.h:87](third_party/crosstool/v18/stable/src/libcxx/include/__thread/support/pthread.h?l=87&cl=669089572):10 (be1eb158bb70fc9cf7be2db70407e512890e5c6e20720cd88c69d7d9c26ea531_0200d5f71908+0x4523d589) (BuildId: ff25ace8b17d9863348bb1759c47246c)
    #2 std::__tsan::recursive_mutex::unlock() [third_party/crosstool/v18/stable/src/libcxx/src/mutex.cpp:64](third_party/crosstool/v18/stable/src/libcxx/src/mutex.cpp?l=64&cl=669089572):11 (be1eb158bb70fc9cf7be2db70407e512890e5c6e20720cd88c69d7d9c26ea531_0200d5f71908+0x4523d589)
    #3 unlock [third_party/llvm/llvm-project/llvm/include/llvm/Support/Mutex.h:47](third_party/llvm/llvm-project/llvm/include/llvm/Support/Mutex.h?l=47&cl=669089572):16 (be1eb158bb70fc9cf7be2db70407e512890e5c6e20720cd88c69d7d9c26ea531_0200d5f71908+0x2bcaf968) (BuildId: ff25ace8b17d9863348bb1759c47246c)
    #4 ~lock_guard [third_party/crosstool/v18/stable/src/libcxx/include/__mutex/lock_guard.h:39](third_party/crosstool/v18/stable/src/libcxx/include/__mutex/lock_guard.h?l=39&cl=669089572):101 (be1eb158bb70fc9cf7be2db70407e512890e5c6e20720cd88c69d7d9c26ea531_0200d5f71908+0x2bcaf968)
    #5 (anonymous namespace)::PerfJITEventListener::notifyObjectLoaded(unsigned long, llvm::object::ObjectFile const&, llvm::RuntimeDyld::LoadedObjectInfo const&) [third_party/llvm/llvm-project/llvm/lib/ExecutionEngine/PerfJITEvents/PerfJITEventListener.cpp:290](https://cs.corp.google.com/piper///depot/google3/third_party/llvm/llvm-project/llvm/lib/ExecutionEngine/PerfJITEvents/PerfJITEventListener.cpp?l=290&cl=669089572):1 (be1eb158bb70fc9cf7be2db70407e512890e5c6e20720cd88c69d7d9c26ea531_0200d5f71908+0x2bcaf968)
    #6 llvm::orc::RTDyldObjectLinkingLayer::onObjEmit(llvm::orc::MaterializationResponsibility&, llvm::object::OwningBinary<llvm::object::ObjectFile>, std::__tsan::unique_ptr<llvm::RuntimeDyld::MemoryManager, std::__tsan::default_delete<llvm::RuntimeDyld::MemoryManager>>, std::__tsan::unique_ptr<llvm::RuntimeDyld::LoadedObjectInfo, std::__tsan::default_delete<llvm::RuntimeDyld::LoadedObjectInfo>>, std::__tsan::unique_ptr<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>>>>, std::__tsan::default_delete<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>>>>>>, llvm::Error) [third_party/llvm/llvm-project/llvm/lib/ExecutionEngine/Orc/RTDyldObjectLinkingLayer.cpp:386](https://cs.corp.google.com/piper///depot/google3/third_party/llvm/llvm-project/llvm/lib/ExecutionEngine/Orc/RTDyldObjectLinkingLayer.cpp?l=386&cl=669089572):10 (be1eb158bb70fc9cf7be2db70407e512890e5c6e20720cd88c69d7d9c26ea531_0200d5f71908+0x2bc404a8) (BuildId: ff25ace8b17d9863348bb1759c47246c)
```
jacobly0 pushed a commit that referenced this pull request Sep 20, 2024

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When SPARC Asan testing is enabled by PR llvm#107405, many Linux/sparc64
tests just hang like
```
#0  0xf7ae8e90 in syscall () from /usr/lib32/libc.so.6
#1  0x701065e8 in __sanitizer::FutexWait(__sanitizer::atomic_uint32_t*, unsigned int) ()
    at compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp:766
#2  0x70107c90 in Wait ()
    at compiler-rt/lib/sanitizer_common/sanitizer_mutex.cpp:35
#3  0x700f7cac in Lock ()
    at compiler-rt/lib/asan/../sanitizer_common/sanitizer_mutex.h:196
#4  Lock ()
    at compiler-rt/lib/asan/../sanitizer_common/sanitizer_thread_registry.h:98
#5  LockThreads ()
    at compiler-rt/lib/asan/asan_thread.cpp:489
#6  0x700e9c8c in __asan::BeforeFork() ()
    at compiler-rt/lib/asan/asan_posix.cpp:157
#7  0xf7ac83f4 in ?? () from /usr/lib32/libc.so.6
Backtrace stopped: previous frame identical to this frame (corrupt stack?)
```
It turns out that this happens in tests using `internal_fork` (e.g.
invoking `llvm-symbolizer`): unlike most other Linux targets, which use
`clone`, Linux/sparc64 has to use `__fork` instead. While `clone`
doesn't trigger `pthread_atfork` handlers, `__fork` obviously does,
causing the hang.

To avoid this, this patch disables `InstallAtForkHandler` and lets the
ASan tests run to completion.

Tested on `sparc64-unknown-linux-gnu`.
jacobly0 pushed a commit that referenced this pull request Oct 9, 2024

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…ext is not fully initialized (llvm#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
jacobly0 pushed a commit that referenced this pull request Nov 20, 2024

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This commit was created on GitHub.com and signed with GitHub’s verified signature.
…onger cause a crash (llvm#116569)

This PR fixes a bug introduced by llvm#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 llvm#110199.

This PR implements the first solution to not introduce any more ABI
changes as llvm#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.
jacobly0 pushed a commit that referenced this pull request Nov 29, 2024

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This commit was created on GitHub.com and signed with GitHub’s verified signature.
…abort (llvm#117603)

Hey guys, I found that Flang's built-in ABORT function is incomplete
when I was using it. Compared with gfortran's ABORT (which can both
abort and print out a backtrace), flang's ABORT implementation lacks the
function of printing out a backtrace. This feature is essential for
debugging and understanding the call stack at the failure point.

To solve this problem, I completed the "// TODO:" of the abort function,
and then implemented an additional built-in function BACKTRACE for
flang. After a brief reading of the relevant source code, I used
backtrace and backtrace_symbols in "execinfo.h" to quickly implement
this. But since I used the above two functions directly, my
implementation is slightly different from gfortran's implementation (in
the output, the function call stack before main is additionally output,
and the function line number is missing). In addition, since I used the
above two functions, I did not need to add -g to embed debug information
into the ELF file, but needed -rdynamic to ensure that the symbols are
added to the dynamic symbol table (so that the function name will be
printed out).

Here is a comparison of the output between gfortran 's backtrace and my
implementation:
gfortran's implemention output:
```
#0  0x557eb71f4184 in testfun2_
        at /home/hunter/plct/fortran/test.f90:5
#1  0x557eb71f4165 in testfun1_
        at /home/hunter/plct/fortran/test.f90:13
#2  0x557eb71f4192 in test_backtrace
        at /home/hunter/plct/fortran/test.f90:17
#3  0x557eb71f41ce in main
        at /home/hunter/plct/fortran/test.f90:18
```
my impelmention output:
```
Backtrace:
#0 ./test(_FortranABacktrace+0x32) [0x574f07efcf92]
#1 ./test(testfun2_+0x14) [0x574f07efc7b4]
#2 ./test(testfun1_+0xd) [0x574f07efc7cd]
#3 ./test(_QQmain+0x9) [0x574f07efc7e9]
#4 ./test(main+0x12) [0x574f07efc802]
#5 /usr/lib/libc.so.6(+0x25e08) [0x76954694fe08]
#6 /usr/lib/libc.so.6(__libc_start_main+0x8c) [0x76954694fecc]
#7 ./test(_start+0x25) [0x574f07efc6c5]
```
test program is:
```
function testfun2() result(err)
  implicit none
  integer :: err
  err = 1
  call backtrace
end function testfun2

subroutine testfun1()
  implicit none
  integer :: err
  integer :: testfun2

  err = testfun2()
end subroutine testfun1

program test_backtrace
  call testfun1()
end program test_backtrace
```
I am well aware of the importance of line numbers, so I am now working
on implementing line numbers (by parsing DWARF information) and
supporting cross-platform (Windows) support.
jacobly0 pushed a commit that referenced this pull request Dec 7, 2024

Verified

This commit was created on GitHub.com and signed with GitHub’s verified signature.
## Description

This PR fixes a segmentation fault that occurs when passing options
requiring arguments via `-Xopenmp-target=<triple>`. The issue was that
the function `Driver::getOffloadArchs` did not properly parse the
extracted option, but instead assumed it was valid, leading to a crash
when incomplete arguments were provided.

## Backtrace

```sh
llvm-project/build/bin/clang++ main.cpp -fopenmp=libomp -fopenmp-targets=powerpc64le-ibm-linux-gnu -Xopenmp-target=powerpc64le-ibm-linux-gnu -o 
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace, preprocessed source, and associated run script.
Stack dump:
0.      Program arguments: llvm-project/build/bin/clang++ main.cpp -fopenmp=libomp -fopenmp-targets=powerpc64le-ibm-linux-gnu -Xopenmp-target=powerpc64le-ibm-linux-gnu -o
1.      Compilation construction
2.      Building compilation actions
 #0 0x0000562fb21c363b llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (llvm-project/build/bin/clang+++0x392f63b)
 #1 0x0000562fb21c0e3c SignalHandler(int) Signals.cpp:0:0
 #2 0x00007fcbf6c81420 __restore_rt (/lib/x86_64-linux-gnu/libpthread.so.0+0x14420)
 #3 0x0000562fb1fa5d70 llvm::opt::Option::matches(llvm::opt::OptSpecifier) const (llvm-project/build/bin/clang+++0x3711d70)
 #4 0x0000562fb2a78e7d clang::driver::Driver::getOffloadArchs(clang::driver::Compilation&, llvm::opt::DerivedArgList const&, clang::driver::Action::OffloadKind, clang::driver::ToolChain const*, bool) const (llvm-project/build/bin/clang+++0x41e4e7d)
 #5 0x0000562fb2a7a9aa clang::driver::Driver::BuildOffloadingActions(clang::driver::Compilation&, llvm::opt::DerivedArgList&, std::pair<clang::driver::types::ID, llvm::opt::Arg const*> const&, clang::driver::Action*) const (.part.1164) Driver.cpp:0:0
 #6 0x0000562fb2a7c093 clang::driver::Driver::BuildActions(clang::driver::Compilation&, llvm::opt::DerivedArgList&, llvm::SmallVector<std::pair<clang::driver::types::ID, llvm::opt::Arg const*>, 16u> const&, llvm::SmallVector<clang::driver::Action*, 3u>&) const (llvm-project/build/bin/clang+++0x41e8093)
 #7 0x0000562fb2a8395d clang::driver::Driver::BuildCompilation(llvm::ArrayRef<char const*>) (llvm-project/build/bin/clang+++0x41ef95d)
 #8 0x0000562faf92684c clang_main(int, char**, llvm::ToolContext const&) (llvm-project/build/bin/clang+++0x109284c)
 #9 0x0000562faf826cc6 main (llvm-project/build/bin/clang+++0xf92cc6)
#10 0x00007fcbf6699083 __libc_start_main /build/glibc-LcI20x/glibc-2.31/csu/../csu/libc-start.c:342:3
#11 0x0000562faf923a5e _start (llvm-project/build/bin/clang+++0x108fa5e)
[1]    2628042 segmentation fault (core dumped)   main.cpp -fopenmp=libomp -fopenmp-targets=powerpc64le-ibm-linux-gnu  -o
```
adriweb pushed a commit to CE-Programming/llvm-project that referenced this pull request Feb 26, 2025
adriweb pushed a commit to CE-Programming/llvm-project that referenced this pull request Feb 26, 2025
adriweb pushed a commit to CE-Programming/llvm-project that referenced this pull request Feb 27, 2025
adriweb pushed a commit to CE-Programming/llvm-project that referenced this pull request Feb 27, 2025
adriweb pushed a commit to CE-Programming/llvm-project that referenced this pull request Mar 3, 2025
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3 participants