The check for `isOSWindows() || isUEFI()` is used in several places
across the codebase. Introducing `isOSWindowsOrUEFI()` in Triple.h
to simplify these checks.
gcc and clang won't complain about calls to deprecated functions, if
you're calling from a function that is deprecated too. However, MSVC
does care, and expands into maaany deprecation warnings for
getFirstNonPHI.
Suppress this by converting the inlineable copy of getFirstNonPHI into a
non-inline copy.
The RemoveDIs project [0] makes debug intrinsics obsolete and to support
this instruction iterators carry an extra bit of debug information. To
maintain debug information accuracy insertion needs to be performed with a
BasicBlock::iterator rather than with Instruction pointers, otherwise the
extra bit of debug information is lost.
To that end, we're deprecating getFirstNonPHI and moveBefore for
instruction pointers. They're replaced by getFirstNonPHIIt and an
iterator-taking moveBefore: switching to the replacement is
straightforwards, and 99% of call-sites need only to unwrap the iterator
with &* or call getIterator() on an Instruction pointer.
The exception is when inserting instructions at the start of a block: if
you call getFirstNonPHI() (or begin() or getFirstInsertionPt()) and then
insert something at that position, you must pass the BasicBlock::iterator
returned into the insertion method. Unwrapping with &* and then calling
getIterator strips the debug-info bit we wish to preserve. Please do
contact us about any use case that's confusing or unclear [1].
[0] https://llvm.org/docs/RemoveDIsDebugInfo.html
[1] https://discourse.llvm.org/t/psa-ir-output-changing-from-debug-intrinsics-to-debug-records/79578
Historically, the main example of *very* large string tables used the
`EmitCharArray` to work around MSVC limitations with string literals,
but that was switched (without removing the API) in order to consolidate
on a nicer emission primitive.
While this large string table in `IntrinsicsImpl.inc` seems to compile
correctly on MSVC without the work around in `EmitCharArray` (and that
this PR adds back to the nicer emission path), other users have
repeatedly hit this MSVC limitation as you can see in the discussion on
PR https://github.com/llvm/llvm-project/pull/120534. This PR teaches the
string offset table emission to look at
the size of the table and switch to the char array emission strategy
when the table becomes too large.
This work around does have the downside of making compile times worse
for large string tables, but that appears unavoidable until we can
identify known good MSVC versions and switch to requiring them for all
LLVM users. It also reduces searchability of the generated string table
-- I looked at emitting a comment with each string but it is tricky
because the escaping rules for an inline comment are different from
those of of a string literal, and there's no real way to turn the string
literal into a comment.
While improving the output in this way, also clean up the output to not
emit an extraneous empty string at the end of the string table, and
update the `StringTable` class to not look for that. It isn't actually
used by anything and is wasteful.
This PR also switches the `IntrinsicsImpl.inc` string tables over to the
new `StringTable` runtime abstraction. I didn't want to do this until
landing the MSVC workaround in case it caused even this example to start
hitting the MSVC bug, but I wanted to switch here so that I could
simplify the API for emitting the string table with the workaround
present. With the two different emission strategies, its important to
use a very exact syntax and that seems better encapsulated in the API.
Last but not least, the `SDNodeInfoEmitter` is updated, including its
tests to match the new output.
This PR should unblock landing
https://github.com/llvm/llvm-project/pull/120534 and letting us switch
all of
Clang's builtins to use string tables. That PR has all the details
motivating the overall effort.
Follow-up patches will try to consolidate the remaining users onto the
single interface, but those at least were easy to separate into
follow-ups and keep this PR somewhat smaller.
As part of the "RemoveDIs" work to eliminate debug intrinsics, we're
replacing methods that use Instruction*'s as positions with iterators. The
call-sites updated in this patch are those where the dyn_cast_or_null cast
utility doesn't compose well with iterator insertion. It can distinguish
between nullptr and a "present" (non-null) Instruction pointer, but not
between a legal and illegal instruction iterator. This can lead to
end-iterator dereferences and thus crashes.
We can improve this in the future (as parent-pointers can now be accessed
from ilist nodes), but for the moment, add explicit tests for end()
iterators at the five call sites affected by this.
To finalise the "RemoveDIs" work removing debug intrinsics, we're
updating call sites that insert instructions to use iterators instead.
This set of changes are those where it's not immediately obvious that
just calling getIterator to fetch an iterator is correct, and one or two
places where more than one line needs to change.
Overall the same rule holds though: iterators generated for the start of
a block such as getFirstNonPHIIt need to be passed into insert/move
methods without being unwrapped/rewrapped, everything else can use
getIterator.
As part of the "RemoveDIs" work to eliminate debug intrinsics, we're
replacing methods that use Instruction*'s as positions with iterators. A
number of these (such as getFirstNonPHIOrDbg) are sufficiently
infrequently used that we can just replace the pointer-returning version
with an iterator-returning version, hopefully without much/any
disruption.
Thus this patch has getFirstNonPHIOrDbg and
getFirstNonPHIOrDbgOrLifetime return an iterator, and updates all
call-sites. There are no concerns about the iterators returned being
converted to Instruction*'s and losing the debug-info bit: because the
methods skip debug intrinsics, the iterator head bit is always false
anyway.
As part of the "RemoveDIs" project, BasicBlock::iterator now carries a
debug-info bit that's needed when getFirstNonPHI and similar feed into
instruction insertion positions. Call-sites where that's necessary were
updated a year ago; but to ensure some type safety however, we'd like to
have all calls to getFirstNonPHI use the iterator-returning version.
This patch changes a bunch of call-sites calling getFirstNonPHI to use
getFirstNonPHIIt, which returns an iterator. All these call sites are
where it's obviously safe to fetch the iterator then dereference it. A
follow-up patch will contain less-obviously-safe changes.
We'll eventually deprecate and remove the instruction-pointer
getFirstNonPHI, but not before adding concise documentation of what
considerations are needed (very few).
---------
Co-authored-by: Stephen Tozer <Melamoto@gmail.com>
As part of the "RemoveDIs" project, BasicBlock::iterator now carries a
debug-info bit that's needed when getFirstNonPHI and similar feed into
instruction insertion positions. Call-sites where that's necessary were
updated a year ago; but to ensure some type safety however, we'd like to
have all calls to moveBefore use iterators.
This patch adds a (guaranteed dereferenceable) iterator-taking
moveBefore, and changes a bunch of call-sites where it's obviously safe
to change to use it by just calling getIterator() on an instruction
pointer. A follow-up patch will contain less-obviously-safe changes.
We'll eventually deprecate and remove the instruction-pointer
insertBefore, but not before adding concise documentation of what
considerations are needed (very few).
This remove some erroneous debug info from tests that should address the
test failures that showed up when the this was previously committed.
This reverts commit 6716ce8b641f0e42e2343e1694ee578b027be0c4.
This started out as trying to combine bf16 fpround to BFCVT2
instructions, but ended up removing the aarch64.neon.nfcvt intrinsics in
favour of generating fpround instructions directly. This simplifies the
patterns and can lead to other optimizations. The BFCVT2 instruction is
adjusted to makes sure the types are valid, and a bfcvt2 is now
generated in more place. The old intrinsics are auto-upgraded to fptrunc
instructions too.
Summary:
This is spelled `ompx_aligned_barrier` when used directly, but wasn't
included in the list of known assumptions. Fix that so now th test
works.
This reverts commit c3a935e3f967f8f22f5db240d145459ee621c1e0.
The only change to the reverted commit is that this also updates
the OCaml bindings according to the C debug-info API changes.
The build failure originally introduced was:
```
FAILED: bindings/ocaml/debuginfo/debuginfo_ocaml.o /b/1/llvm-clang-x86_64-expensive-checks-debian/build/bindings/ocaml/debuginfo/debuginfo_ocaml.o
cd /b/1/llvm-clang-x86_64-expensive-checks-debian/build/bindings/ocaml/debuginfo && /usr/bin/ocamlfind ocamlc -c /b/1/llvm-clang-x86_64-expensive-checks-debian/build/bindings/ocaml/debuginfo/debuginfo_ocaml.c -ccopt "-I/b/1/llvm-clang-x86_64-expensive-checks-debian/llvm-project/llvm/bindings/ocaml/debuginfo/../llvm -D_GNU_SOURCE -D_DEBUG -D_GLIBCXX_ASSERTIONS -DEXPENSIVE_CHECKS -D_GLIBCXX_DEBUG -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/b/1/llvm-clang-x86_64-expensive-checks-debian/build/include -I/b/1/llvm-clang-x86_64-expensive-checks-debian/llvm-project/llvm/include -DNDEBUG "
/b/1/llvm-clang-x86_64-expensive-checks-debian/build/bindings/ocaml/debuginfo/debuginfo_ocaml.c: In function ‘llvm_dibuild_create_object_pointer_type’:
/b/1/llvm-clang-x86_64-expensive-checks-debian/build/bindings/ocaml/debuginfo/debuginfo_ocaml.c:620:30: error: too few arguments to function ‘LLVMDIBuilderCreateObjectPointerType’
620 | LLVMMetadataRef Metadata = LLVMDIBuilderCreateObjectPointerType(
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from /b/1/llvm-clang-x86_64-expensive-checks-debian/build/bindings/ocaml/debuginfo/debuginfo_ocaml.c:23:
/b/1/llvm-clang-x86_64-expensive-checks-debian/llvm-project/llvm/include/llvm-c/DebugInfo.h:880:17: note: declared here
880 | LLVMMetadataRef LLVMDIBuilderCreateObjectPointerType(LLVMDIBuilderRef Builder,
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
```
print-after-all is useful for diffing IR between two passes. When one of
the two is a function pass, and the other is a loop pass, the diff
becomes useless. Add an option which prints the entire function for loop
passes.
Came up recently with some nodebug case on codeview, that caused a null
entry in elements and crashed LLVM.
Original clang fix to avoid generating IR like this: 504dd577675e8c85cdc8525990a7c8b517a38a89
If a pointer gets freed, it may not be dereferenceable any longer, even
though there is a dominating dereferenceable assumption. As first step,
only consider assumptions if the pointer value cannot be freed if
UseDerefAtPointSemantics is used.
PR: https://github.com/llvm/llvm-project/pull/123196
This patch adds possibility to specify alignment for
llvm.masked.expandload/llvm.masked.compressstore intrinsics in IRBuilder
(this is mostly NFC for now since it's only used in MemorySanitizer, but
there is an intention to generate these intrinsics in the compiler
passes, e.g. in LoopVectorizer)
66badf2 (VT: teach a special-case optz about samesign) introduced a
compile-time regression due to the use of CmpPredicate::getMatching,
which is unnecessarily inefficient. Introduce
CmpPredicate::getPreferredSignedPredicate, which alleviates the
inefficiency problem and squashes the compile-time regression.
CmpPredicate::getMatching implicitly assumes that both predicates are
integer-predicates, and this has led to a crash being reported in
VectorCombine after e409204 (VectorCombine: teach foldExtractedCmps
about samesign). FP predicates are simple enough to handle as there is
never any samesign information associated with them: hence handle them
in CmpPredicate::getMatching, fixing the VectorCombine crash and
guarding against future incorrect usages.
Create an abstraction over isImplied{True,False}ByMatchingCmp to
faithfully communicate the result of both functions, cleaning up code in
callsites. While at it, fix a bug in the implied-false version of the
function, which was inadvertedenly dropping samesign information.
This introduces the `captures` attribute as described in:
https://discourse.llvm.org/t/rfc-improvements-to-capture-tracking/81420
This initial patch only introduces the IR/bitcode support for the
attribute and its in-memory representation as `CaptureInfo`. This will
be followed by a patch to upgrade and remove the `nocapture` attribute,
and then by actual inference/analysis support.
Based on the RFC feedback, I've used a syntax similar to the `memory`
attribute, though the only "location" that can be specified is `ret`.
I've added some pretty extensive documentation to LangRef on the
semantics. One non-obvious bit here is that using ptrtoint will not
result in a "return-only" capture, even if the ptrtoint result is only
used in the return value. Without this requirement we wouldn't be able
to continue ordinary capture analysis on the return value.
Move isImplied{True,False}ByMatchingCmp from CmpInst to ICmpInst, so
that it can operate on CmpPredicate instead of CmpInst::Predicate, and
teach it about samesign. There are two callers of this function, and we
choose to migrate the one in ValueTracking, namely
isImpliedCondMatchingOperands to CmpPredicate, hence teaching it about
samesign, with visible test impact.
This is a split-off from #109833 and only adds code relating to checking
if a struct-returning call can be vectorized.
This initial patch only allows the case where all users of the struct
return are `extractvalue` operations that can be widened.
```
%call = tail call { float, float } @foo(float %in_val)
%extract_a = extractvalue { float, float } %call, 0
%extract_b = extractvalue { float, float } %call, 1
```
Note: The tests require the VFABI changes from #119000 to pass.
This PR is motivated by a mismatch we discovered between compilation
results with vs. without `-g3`. We noticed this when compiling SPEC2017
testcases. The specific instance we saw is fixed in this PR by modifying
a guard (see below), but it is likely similar instances exist elsewhere
in the codebase.
The specific case fixed in this PR manifests itself in the `SimplifyCFG`
pass doing different things depending on whether DebugInfo is generated
or not. At the end of this comment, there is reduced example code that
shows the behavior in question.
The differing behavior has two root causes:
1. Commit https://github.com/llvm/llvm-project/commit/c07e19b adds loop
metadata including debug locations to loops that otherwise would not
have loop metadata
2. Commit https://github.com/llvm/llvm-project/commit/ac28efa6c100 adds
a guard to a simplification action in `SImplifyCFG` that prevents it
from simplifying away loop metadata
So, the change in 2. does not consider that when compiling with debug
symbols, loops that otherwise would not have metadata that needs
preserving, now have debug locations in their loop metadata. Thus, with
`-g3`, `SimplifyCFG` behaves differently than without it.
The larger issue is that while debug info is not supposed to influence
the final compilation result, commits like 1. blur the line between what
is and is not debug info, and not all optimization passes account for
this.
This PR does not address that and rather just modifies this particular
guard in order to restore equivalent behavior between debug and
non-debug builds in this one instance.
---
Here is a reduced version of a file from `f526.blender_r` that showcases
the behavior in question:
```C
struct LinkNode;
typedef struct LinkNode {
struct LinkNode *next;
void *link;
} LinkNode;
void do_projectpaint_thread_ph_v_state() {
int *ps = do_projectpaint_thread_ph_v_state;
LinkNode *node;
while (do_projectpaint_thread_ph_v_state)
for (node = ps; node; node = node->next)
;
}
```
Compiling this with and without DebugInfo, and then disassembling the
results, leads to different outcomes (tested on SystemZ and X86). The
reason for this is that the `SimplifyCFG` pass does different things in
either case.
This patch updates the `VFABIDemangler` to support vector functions that
return struct types. For example, a vector variant of `sincos` that
returns a vector of sine values and a vector of cosine values within a
struct.
This patch also adds some helpers for vectorizing types (including
struct types). Some of these are used in the `VFABIDemangler`, and
others will be used in subsequent patches, so this patch simply adds
tests for them.
This makes sure no optimizations are applied that assume the
bigger alignment or size, which could be incorrect if we link
together with non-instrumented code.
Improve the non-fatal cases to use DiagnosticInfo, which will now
provide a location. The allocators attempt to report different errors
if it happens to see inline assembly is involved (this detection is
quite unreliable) using srcloc instead of dbgloc. For now, leave this
behavior unchanged. I think reporting the full location and context
function would be more useful.
Strip hash_value() for CmpPredicate, as different callers have different
hashing use-cases. In this case, there is just one caller, namely
EarlyCSE, which calls hash_combine() on a CmpPredicate, which used to
call hash_combine() on a CmpInst::Predicate prior to 4a0d53a
(PatternMatch: migrate to CmpPredicate). This has uncovered a bug where
two icmp instructions differing in just the fact that one of them has
the samesign flag on it are hashed differently, leading to divergent
hashing, and a crash. Fix this crash by dropping samesign information on
icmp instructions before hashing them, preserving the former behavior.
Fixes#119893.
With the introduction of CmpPredicate in 51a895a (IR: introduce struct
with CmpInst::Predicate and samesign), PatternMatch is one of the first
key pieces of infrastructure that must be updated to match a CmpInst
respecting samesign information. Implement this change to Cmp-matchers.
This is a preparatory step in migrating the codebase over to
CmpPredicate. Since we no functional changes are desired at this stage,
we have chosen not to migrate CmpPredicate::operator==(CmpPredicate)
calls to use CmpPredicate::getMatching(), as that would have visible
impact on tests that are not yet written: instead, we call
CmpPredicate::operator==(Predicate), preserving the old behavior, while
also inserting a few FIXME comments for follow-ups.
