Currently managed variables are emitted as undefined symbols, which
causes difficulty for diagnosing undefined symbols for non-managed
variables.

This patch transforms managed variables in device compilation so that
they can be emitted as normal variables.

Reviewed by: Artem Belevich

Differential Revision: https://reviews.llvm.org/D96195

The non-flag setting variants of instructions may have different regclass
requirements. If so, we need to constrain them.

Differential Revision: https://reviews.llvm.org/D97343

This is for XCOFF DWARF support.

Seems when DWARF debug is enable, symbol 0 has special usage
for AIX binder. At least, symbol 0 can not be the .text
section. Otherwise, we get some binding time error.

Add correct C_FILE symbol at index 0 here to make AIX binder
work.

Reviewed By: hubert.reinterpretcast

Differential Revision: https://reviews.llvm.org/D97117

This reverts commit c4a91444.
Breaks check-llvm everywhere, see https://reviews.llvm.org/D97242#2583716

{D95809} introduced a mechanism for synthetic symbol creation of personality
pointers. When multiple section relocations referred to the same personality
pointer, it would deduplicate them. However, it neglected to consider that we
could have symbol relocations that also refer to the same personality pointer.
This diff fixes it.

In practice, this mix of relocations arises when there is a statically-linked
personality routine that is referenced from multiple object files. Within the
same object file, it will be referred to via section relocations, but
(obviously) other object files will refer to it via symbol relocations. Failing
to deduplicate these references resulted in us going over the
3-personality-pointer limit when linking some larger applications.

Fixes llvm.org/PR48389.

Reviewed By: #lld-macho, thakis, alexshap

Differential Revision: https://reviews.llvm.org/D97245

The silent failures had confused me a few times.

I haven't added a similar check for platform yet as we don't yet have logic to
infer the platform automatically, and so adding that check would require
updating dozens of test files.

Reviewed By: #lld-macho, thakis, alexshap

Differential Revision: https://reviews.llvm.org/D97209

I've adjusted the RelocAttrBits to better fit the semantics of
the relocations. In particular:

1. *_UNSIGNED relocations are no longer marked with the `TLV` bit, even
   though they can occur within TLV sections. Instead the `TLV` bit is
   reserved for relocations that can reference thread-local symbols, and
   *_UNSIGNED relocations have their own `UNSIGNED` bit. The previous
   implementation caused TLV and regular UNSIGNED semantics to be
   conflated, resulting in rebase opcodes being incorrectly emitted for TLV
   relocations.

2. I've added a new `POINTER` bit to denote non-relaxable GOT
   relocations. This distinction isn't important on x86 -- the GOT
   relocations there are either relaxable or non-relaxable loads -- but
   arm64 has `GOT_LOAD_PAGE21` which loads the page that the referent
   symbol is in (regardless of whether the symbol ends up in the GOT). This
   relocation must reference a GOT symbol (so must have the `GOT` bit set)
   but isn't itself relaxable (so must not have the `LOAD` bit). The
   `POINTER` bit is used for relocations that *must* reference a GOT
   slot.

3. A similar situation occurs for TLV relocations.

4. ld64 supports both a pcrel and an absolute version of
   ARM64_RELOC_POINTER_TO_GOT. But the semantics of the absolute version
   are pretty weird -- it results in the value of the GOT slot being
   written, rather than the address. (That means a reference to a
   dynamically-bound slot will result in zeroes being written.) The
   programs I've tried linking don't use this form of the relocation, so
   I've dropped our partial support for it by removing the relevant
   RelocAttrBits.

Reviewed By: alexshap

Differential Revision: https://reviews.llvm.org/D97031

Just something I noticed while debugging arm relocations...

Reviewed By: #lld-macho, thakis

Differential Revision: https://reviews.llvm.org/D97078

This avoids unnecessary async overhead in situations that won't benefit from it.

We may need to do some customization for DWARF unit length in DWARF
section headers for some targets for some code generation path.

For example, for XCOFF in assembly path, AIX assembler does not require
the debug section containing its debug unit length in the header.

Move emitDwarfUnitLength to MCStreamer class so that we can do
customization in different Streamers

Reviewed By: ikudrin

Differential Revision: https://reviews.llvm.org/D95932

The maintainer of libdwarf kindly provided this patch with a bunch of
historic DWARF extensions that are missing from Dwarf.def. This list
is helpful to avoid potential conflicts in the user-defined vendor
extension space in the future.

Patch by David Anderson!

Differential Revision: https://reviews.llvm.org/D97242

Blocks that contain only a single branch instruction to the next block can be skipped in analyzing the loop-nest structure.
This is currently done by `getSingleSuccessor()`.
However, the branch instruction might have multiple targets which happen to all be the same.
In this case, the block should still be considered as empty and skipped.

An example is `test/Transforms/LoopInterchange/update-condbranch-duplicate-successors.ll` (the LIT test for this patch is modified from it as well).

Reviewed By: Whitney

Differential Revision: https://reviews.llvm.org/D97286

This is a simple patch to update SimplifyCFG's passingValueIsAlwaysUndefined to inspect more attributes.

A new function `CallBase::isPassingUndefUB` checks attributes that imply noundef.

Reviewed By: spatel

Differential Revision: https://reviews.llvm.org/D97244

This reverts commit 7f9d5d6e.
Breaks check-clang everywhere, see https://reviews.llvm.org/D96638#2583608

Reviewed By: mehdi_amini

Differential Revision: https://reviews.llvm.org/D97141

This prevents a bug in the pass instrumentation implementation where the main thread would end up with a different pass manager in different runs of the pass.

This got me pretty recently... TrailingObjects cannot be copied or
moved, since they need to be pre-allocated. This patch deletes the copy
and move operations (plus re-adds the default ctor).

Differential Revision: https://reviews.llvm.org/D97324

The order in which the nested calls to Builder.buildWhatever are
evaluated in differs between GCC and Clang.

This caused a bot failure because the MIR in the testcase was
coming out in a different order than expected.

Rather than using nested calls, pull them out in order to fix the
order of evaluation.

And delete the SmallPtrSetImpl overload.

While here, decrease inline element counts from 8 to 4. See D97128 for the choice.

Reviewed By: tejohnson

Differential Revision: https://reviews.llvm.org/D97257

While here, decrease inline element counts from 8 to 4. See D97128 for the choice.

Depends on D97128 (which added a new SmallVecImpl overload for collectUsedGlobalVariables).

Reviewed By: tejohnson

Differential Revision: https://reviews.llvm.org/D97139

Iterating on `SmallPtrSet<GlobalValue *, 8>` with more than 8 elements
is not deterministic. Use a SmallVector instead because `Used` is guaranteed to contain unique elements.

While here, decrease inline element counts from 8 to 4. The number of
`llvm.used`/`llvm.compiler.used` elements is usually 0 or 1. For full
LTO/hybrid LTO, the number may be large, so we need to be careful.

According to tejohnson's analysis https://reviews.llvm.org/D97128#2582399 , 4 is
good for a large project with WholeProgramDevirt, when available_externally
vtables are placed in the llvm.compiler.used set.

Differential Revision: https://reviews.llvm.org/D97128

The fix in 3c4c2050 caused an assert in
the case of a pure virtual base class. In that case, the vTableFuncs
list on the summary will be empty, so we were hitting the new assert
that the linkage type was not available_externally.

In the case of pure virtual, we do not want to assert, and additionally
need to set VS so that we don't treat it conservatively and quit the
analysis of the type id early.

This exposed a pre-existing issue where we were not updating the vcall
visibility on pure virtual functions when whole program visibility was
specified. We were skipping updating the visibility on any global vars
that didn't have any vTableFuncs, which meant all pure virtual were not
updated, and the later analysis would block any devirtualization of
calls that had a type id used on those pure virtual vtables (see the
handling in the other code modified in this patch). Simply remove that
check. It will mean that we may update the vcall visibility on global
vars that aren't vtables, but that setting is ignored for any global
vars that didn't have type metadata anyway.

Added a new test case that asserted without removing the assert, and
that requires the other fixes in this patch (updateVCallVisibilityInIndex
and not skipping all vtables without virtual funcs) to get a successful
devirtualization with index-only WPD. I added cases to test hybrid and
regular LTO for completeness, although those already worked without the
fixes here.

With this final fix, a clang multistage bootstrap with WPD builds and
runs all tests successfully.

Differential Revision: https://reviews.llvm.org/D97126

Demonstrate how to add RISC-V V builtins and lower them to IR intrinsics for V extension.

Authored-by: Roger Ferrer Ibanez <rofirrim@gmail.com>
Co-Authored-by: Hsiangkai Wang <kai.wang@sifive.com>

Differential Revision: https://reviews.llvm.org/D93446

This class is to serve as a replacement for llvm::StringRef as part of
the plans to limit dependency on other parts of LLVM. One use of
llvm::StringRef in MPFRWrapper has been replaced with the new class.

Reviewed By: lntue

Differential Revision: https://reviews.llvm.org/D97330

Differential Revision: https://reviews.llvm.org/D96985

This is a part of https://reviews.llvm.org/D95835.

Reviewed-by: morehouse

Differential Revision: https://reviews.llvm.org/D97302

Adds "REQUIRES: asserts", since the test uses debug messages

This CL is not big but contains changes that span multiple analyses and
passes. This description is very long because it tries to explain basics
on what each pass/analysis does and why we need this change on top of
that. Please feel free to skip parts that are not necessary for your
understanding.

---

`WasmEHFuncInfo` contains the mapping of <EH pad, the EH pad's next
unwind destination>. The value (unwind dest) here is where an exception
should end up when it is not caught by the key (EH pad). We record this
info in WasmEHPrepare to fix catch mismatches, because the CFG itself
does not have this info. A CFG only contains BBs and
predecessor-successor relationship between them, but in `WasmEHFuncInfo`
the unwind destination BB is not necessarily a successor or the key EH
pad BB. Their relationship can be intuitively explained by this C++ code
snippet:
```
try {
  try {
    foo();
  } catch (int) { // EH pad
    ...
  }
} catch (...) {   // unwind destination
}
```
So when `foo()` throws, it goes to `catch (int)` first. But if it is not
caught by it, it ends up in the next unwind destination `catch (...)`.
This unwind destination is what you see in `catchswitch`'s
`unwind label %bb` part.

---

`WebAssemblyExceptionInfo` groups exceptions so that they can be sorted
continuously together in CFGSort, as we do for loops. What this analysis
does is very simple: it creates a single `WebAssemblyException` per EH
pad, and all BBs that are dominated by that EH pad are included in this
exception. We also identify subexception relationship in this way: if
EHPad A domiantes EHPad B, EHPad B's exception is a subexception of
EHPad A's exception.

This simple rule turns out to be incorrect in some cases. In
`WasmEHFuncInfo`, if EHPad A's unwind destination is EHPad B, it means
semantically EHPad B should not be included in EHPad A's exception,
because it does not make sense to rethrow/delegate to an inner scope.
This is what happened in CFGStackify as a result of this:
```
try
  try
  catch
    ...   <- %dest_bb is among here!
  end
delegate %dest_bb
```

So this patch adds a phase in `WebAssemblyExceptionInfo::recalculate` to
make sure excptions' unwind destinations are not subexceptions of
their unwind sources in `WasmEHFuncInfo`.

But this alone does not prevent `dest_bb` in the example above from
being sorted within the inner `catch`'s exception, even if its exception
is not a subexception of that `catch`'s exception anymore, because of
how CFGSort works, which will be explained below.

---

CFGSort places BBs within the same `SortRegion` (loop or exception)
continuously together so they can be demarcated with `loop`-`end_loop`
or `catch`-`end_try` in CFGStackify.

`SortRegion` is a wrapper for one of `MachineLoop` or
`WebAssemblyException`. `SortRegionInfo` already does some complicated
things because there discrepancies between those two data structures.
`WebAssemblyException` is what we control, and it is defined as an EH
pad as its header and BBs dominated by the header as its BBs (with a
newly added exception of unwind destinations explained in the previous
paragraph). But `MachineLoop` is an LLVM data structure and uses the
standard loop detection algorithm. So by the algorithm, BBs that are 1.
dominated by the loop header and 2. have a path back to its header.
Because of the second condition, many BBs that are dominated by the loop
header are not included in the loop. So BBs that contain `return` or
branches to outside of the loop are not technically included in
`MachineLoop`, but they can be sorted together with the loop with no
problem.

Maybe to relax the condition, in CFGSort, when we are in a `SortRegion`
we allow sorting of not only BBs that belong to the current innermost
region but also BBs that are by the current region header.
(This was written this way from the first version written by Dan, when
only loops existed.) But now, we have cases in exceptions when EHPad B
is the unwind destination for EHPad A, even if EHPad B is dominated by
EHPad A it should not be included in EHPad A's exception, and should not
be sorted within EHPad A.

One way to make things work, at least correctly, is change `dominates`
condition to `contains` condition for `SortRegion` when sorting BBs, but
this will change compilation results for existing non-EH code and I
can't be sure it will not degrade performance or code size. I think it
will degrade performance because it will force many BBs dominated by a
loop, which don't have the path back to the header, to be placed after
the loop and it will likely to create more branches and blocks.

So this does a little hacky check when adding BBs to `Preferred` list:
(`Preferred` list is a ready list. CFGSort maintains ready list in two
priority queues: `Preferred` and `Ready`. I'm not very sure why, but it
was written that way from the beginning. BBs are first added to
`Preferred` list and then some of them are pushed to `Ready` list, so
here we only need to guard condition for `Preferred` list.)

When adding a BB to `Preferred` list, we check if that BB is an unwind
destination of another BB. To do this, this adds the reverse mapping,
`UnwindDestToSrc`, and getter methods to `WasmEHFuncInfo`. And if the BB
is an unwind destination, it checks if the current stack of regions
(`Entries`) contains its source BB by traversing the stack backwards. If
we find its unwind source in there, we add the BB to its `Deferred`
list, to make sure that unwind destination BB is added to `Preferred`
list only after that region with the unwind source BB is sorted and
popped from the stack.

---

This does not contain a new test that crashes because of this bug, but
this fix changes the result for one of existing test case. This test
case didn't crash because it fortunately didn't contain `delegate` to
the incorrectly placed unwind destination BB.

Fixes https://github.com/emscripten-core/emscripten/issues/13514.

Reviewed By: dschuff, tlively

Differential Revision: https://reviews.llvm.org/D97247

Update scan-build-py to be able to trigger sarif-html output format in clang static analyzer.

NOTE: testcase `test_sarif_and_html_creates_sarif_and_html_reports` will fail if the default clang does not have change https://reviews.llvm.org/D96389 . This can be remediated by pointing the default clang in arguments.py to a locally built clang. I was unable to figure out where these particular tests for scan-build-py are being invoked (aside from manually), so any help there would be greatly appreciated.

Reviewed By: aabbaabb, xazax.hun

Differential Revision: https://reviews.llvm.org/D96570

In every catchpad except `catch (...)`, we add a call to
`_Unwind_CallPersonality`, which is a wapper to call the personality
function. (In most of other Itanium-based architectures the call is done
from libunwind, but in wasm we don't have the control over the VM.)
Because the personatlity function is called to figure out whether the
current exception is a type we should catch, such as `int` or
`SomeClass&`, `catch (...)` does not need the personality function call.
For the same reason, all cleanuppads don't need it.

When we call `_Unwind_CallPersonality`, we store some necessary info in
a data structure called `__wasm_lpad_context` of type
`_Unwind_LandingPadContext`, which is defined  in the wasm's port of
libunwind in Emscripten. Also the personality wrapper function returns
some info (selector and the caught pointer) in that data structure, so
it is used as a medium for communication.

One of the info we need to store is the address for LSDA info for the
current function. `wasm.lsda()` intrinsic returns that address. (This
intrinsic will be lowered to a symbol that points to the LSDA address.)
The simpliest thing is call `wasm.lsda()` every time we need to call
`_Unwind_CallPersonality` and store that info in `__wasm_lpad_context`
data structure. But we tried to be better than that (D77423 and some
more previous CLs), so if catchpad A dominates catchpad B and catchpad A
is not `catch (...)`, we didn't insert `wasm.lsda()` call in catchpad B,
thinking that the LSDA address is the same for a single function and we
already visited catchpad A and `__wasm_lpad_context.lsda` field would
already have that value.

But this can be incorrect if there is a call to another function, which
also can have the personality function and LSDA, between catchpad A and
catchpad B, because `__wasm_lpad_context` is a globally defined
structure and the callee function will overwrite its `lsda` field.

So in this CL we don't try to do any optimizaions on adding
`wasm.lsda()` call; we store the result of `wasm.lsda()` every time we
call `_Unwind_CallPersonality`. We can do some complicated analysis,
like checking if there is a function call between the dominating
catchpad and the current catchpad, but at this time it seems overkill.

This deletes three tests because they all tested `wasm.ldsa()` call
optimization.

Fixes https://github.com/emscripten-core/emscripten/issues/13548.

Reviewed By: tlively

Differential Revision: https://reviews.llvm.org/D97309

llvm::parallelTransformReduce does not schedule work on the caller thread, which becomes very costly for
the inliner where a majority of SCCs are small, often ~1 element. The switch to llvm::parallelForEach solves this,
and also aligns the implementation with the PassManager (which realistically should share the same implementation).

This change dropped compile time on an internal benchmark by ~1(25%) second.

Differential Revision: https://reviews.llvm.org/D96086

A majority of operations have a very small number of interfaces, which means that the cost of using a hash map is generally larger for interface lookups than just a binary search. In the future when there are a number of operations with large amounts of interfaces, we can switch to a hybrid approach that optimizes lookups based on the number of interfaces. For now, however, a binary search is the best approach.

This dropped compile time on a largish TF MLIR module by 20%(half a second).

Differential Revision: https://reviews.llvm.org/D96085

These would fail a verifier check in a future change.

https://bugs.llvm.org/show_bug.cgi?id=40858

CheckShadow is now called for each binding in the structured binding to make sure it does not shadow any other variable in scope. This does use a custom implementation of getShadowedDeclaration though because a BindingDecl is not a VarDecl

Added a few unit tests for this. In theory though all the other shadow unit tests should be duplicated for the structured binding variables too but whether it is probably not worth it as they use common code. The MyTuple and std interface code has been copied from live-bindings-test.cpp

Reviewed By: rsmith

Differential Revision: https://reviews.llvm.org/D96147

When targeting a MSVC triple, --dependant-libs with the name of the clang runtime library for profiling is added to the command line args. In it's current implementations clang_rt.profile-<ARCH> is chosen as the name. When building a distribution using LLVM_ENABLE_PER_TARGET_RUNTIME_DIR this fails, due to the runtime file names not having an architecture suffix in the filename.

This patch refactors getCompilerRT and getCompilerRTBasename to always consider per-target runtime directories. getCompilerRTBasename now simply returns the filename component of the path found by getCompilerRT

Differential Revision: https://reviews.llvm.org/D96638

In DWARF v4 compile units go in .debug_info and type units go in
.debug_types. However, in v5 both kinds of units are in .debug_info.
Therefore we can't decide whether to use the CU or TU index just by
looking at which section we're reading from. We have to wait until we
have read the unit type from the header.

Differential Revision: https://reviews.llvm.org/D96194

When computing dense address, a vectorized index must be accounted
for properly. This bug was formerly undetected because we get 0 * prev + i
in most cases, which folds away the scalar part. Now it works for all cases.

Reviewed By: bixia

Differential Revision: https://reviews.llvm.org/D97317

Removes unused function from FatalError.h.

Differential revision: https://reviews.llvm.org/D97328