When two interposable functions are merged, we cannot replace
uses and have to emit calls to a common internal function. However,
writeThunk() will not actually emit a thunk if the function is too
small. This leaves us in a broken state where mergeTwoFunctions
already rewired the functions, but writeThunk doesn't do anything.
This patch changes the implementation so that:
* writeThunk() does just that.
* The direct replacement of calls is moved into mergeTwoFunctions()
into the non-interposable case only.
* isThunkProfitable() is extracted and will be called for
the non-iterposable case always, and in the interposable case
only if uses are still left after replacement.
This issue has been introduced in https://reviews.llvm.org/D34806,
where the code for checking thunk profitability has been moved.
Differential Revision: https://reviews.llvm.org/D46804
Reviewed By: whitequark
llvm-svn: 332342
Summary:
Part of the InstCombine code for simplifying GEPs looks through
addrspacecasts. However, this was done by updating a variable
also used by the next transformation, for marking GEPs as
inbounds. This led to replacing a GEP with a similar instruction
in a different addrspace, which caused an assertion failure in RAUW.
This caused julia issue https://github.com/JuliaLang/julia/issues/27055
Patch by Jeff Bezanson <jeff@juliacomputing.com>
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D46722
llvm-svn: 332302
The DEBUG() macro is very generic so it might clash with other projects.
The renaming was done as follows:
- git grep -l 'DEBUG' | xargs sed -i 's/\bDEBUG\s\?(/LLVM_DEBUG(/g'
- git diff -U0 master | ../clang/tools/clang-format/clang-format-diff.py -i -p1 -style LLVM
- Manual change to APInt
- Manually chage DOCS as regex doesn't match it.
In the transition period the DEBUG() macro is still present and aliased
to the LLVM_DEBUG() one.
Differential Revision: https://reviews.llvm.org/D43624
llvm-svn: 332240
This is a CodeExtractor improvement which adds support for extracting blocks
which have exception handling constructs if that is legal to do. CodeExtractor
performs validation checks to ensure that extraction is legal when it finds
invoke instructions or EH pads (landingpad, catchswitch, or cleanuppad) in
blocks to be extracted.
I have also added an option to allow extraction of blocks with alloca
instructions, but no validation is done for allocas. CodeExtractor caller has
to validate it himself before allowing alloca instructions to be extracted.
By default allocas are still not allowed in extraction blocks.
Differential Revision: https://reviews.llvm.org/D45904
llvm-svn: 332151
Let separate-const-offset-from-gep pass handle trunc() when it calculates
constant offset relative to base. The pass itself may insert trunc()
instructions when it canonicalises array indices to pointer-size integers
and needs to handle trunc() in order to evaluate the offset.
Differential Revision: https://reviews.llvm.org/D46732
llvm-svn: 332142
Summary:
This change adds handling of the atomic memset intrinsic to the
code path that simplifies the regular memset. In practice this means
that we will now also expand a small constant-length atomic memset
into a single unordered atomic store.
Reviewers: apilipenko, skatkov, mkazantsev, anna, reames
Reviewed By: reames
Subscribers: reames, llvm-commits
Differential Revision: https://reviews.llvm.org/D46660
llvm-svn: 332132
Phi nodes can reside in live blocks but one of their incoming
arguments can come from a dead block. Dead blocks and reassociate
don't play nice together. In fact, reassociate performs an RPO
as a first step to avoid processing dead blocks.
The reason why Reassociate might not fixpoint when examining
dead blocks is that the following:
%xor0 = xor i16 %xor1, undef
%xor1 = xor i16 %xor0, undef
is perfectly valid LLVM IR (if it appears in a dead block),
so the worklist algorithm keeps pushing the two instructions for
reexamination. Note that this is not Reassociate fault, at least
not entirely. It's llvm that has a weird definition of dominance.
Fixes PR37390.
llvm-svn: 332100
Summary:
This change reworks the handling of atomic memcpy within the instcombine pass.
Previously, a constant length atomic memcpy would be lowered into loads & stores
as long as no more than 16 load/store pairs are created. This is quite different
from the lowering done for a non-atomic memcpy; which only ever lowers into a single
load/store pair of no more than 8 bytes. Larger constant-sized memcpy calls are
expanded to load/stores in later passes, such as SelectionDAG lowering.
In this change the behaviour for atomic memcpy is unified with non-atomic memcpy;
atomic memcpy is now treated in the same was as non-atomic memcpy has always been.
We leave it to later passes to lower longer-length atomic memcpy calls.
Due to the structure of the pass's handling of memtransfer intrinsics, this change
also gives us handling of atomic memmove that we did not previously have.
Reviewers: apilipenko, skatkov, mkazantsev, anna, reames
Reviewed By: reames
Subscribers: reames, llvm-commits
Differential Revision: https://reviews.llvm.org/D46658
llvm-svn: 332093
Summary:
https://bugs.llvm.org/show_bug.cgi?id=34897 demonstrates an incorrect
coroutine frame allocation elision in the coro-elide pass. The elision
is performed on the basis that the SSA variables from all llvm.coro.begin
are directly referenced in subsequent llvm.coro.destroy instructions.
However, this ignores the fact that the function may exit through paths
that do not run these destroy instructions. In the sample program from
PR34897, for example, the llvm.coro.destroy instruction is only
executed in exception handling code. When the coroutine function exits
normally, llvm.coro.destroy is not called. Eliding the allocation in
this case causes a subsequent reference to the coroutine handle from
outside of the function to access freed memory.
To fix the issue, when finding an llvm.coro.destroy for each llvm.coro.begin,
only consider llvm.coro.destroy that are executed along non-exceptional paths.
Test Plan:
1. Download the sample program from
https://bugs.llvm.org/show_bug.cgi?id=34897, compile it with
`clang++ -fcoroutines-ts -stdlib=libc++ -std=c++1z -O2`, and run it.
It should print `"run1\ncheck1\nrun2\ncheck2"` and then exit
successfully.
2. Compile https://godbolt.org/g/mCKfnr and confirm it is still
optimized to a single instruction, 'return 1190'.
3. `check-llvm`
Reviewers: rsmith, GorNishanov, eric_niebler
Reviewed By: GorNishanov
Subscribers: andrewrk, lewissbaker, EricWF, llvm-commits
Differential Revision: https://reviews.llvm.org/D43242
llvm-svn: 332077
Summary:
Ship kNetBSD_ShadowOffset32 set to 1ULL << 30.
This is prepared for the amd64 kernel runtime.
Sponsored by <The NetBSD Foundation>
Reviewers: vitalybuka, joerg, kcc
Reviewed By: vitalybuka
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D46724
llvm-svn: 332069
We found current sampleFDO had a performance issue when triaging a regression.
For a callsite with inline instance in the profile, even if hot callsite inliner
cannot inline it, it may still execute enough times and should not be treated as
cold in regular inliner later. However, currently if such callsite is not inlined
by hot callsite inliner, and the BB where the callsite locates doesn't get
samples from other instructions inside of it, the callsite will have no profile
metadata annotated. In regular inliner cost analysis, if the callsite has no
profile annotated and its caller has profile information, it will be treated as
cold.
The fix changes the isCallsiteHot check and chooses to compare
CallsiteTotalSamples with hot cutoff value computed by ProfileSummaryInfo.
Differential Revision: https://reviews.llvm.org/D45377
llvm-svn: 332058
This commit adds a wrapper for std::distance() which works with ranges.
As it would be a common case to write `distance(predecessors(BB))`, this
also introduces `pred_size()` and `succ_size()` helpers to make that
easier to write.
Differential Revision: https://reviews.llvm.org/D46668
llvm-svn: 332057
The bitwidth of the operation should always be wider than the result width of the truncate since we don't recurse through any width changing operations.
llvm-svn: 332055
This reverts commit SVN r331889, which could trigger failed
assertions for cases where the snprintf function is declared
with a vaguely differing signature (e.g. being defined as
static inline), see PR37408.
llvm-svn: 332043
Summary:
This change teaches DSE that the atomic memory intrinsics can be overwriten
partially in the same way as the non-atomic forms. Specifically, that the
atomic memcpy & memset can be shortened at the end and that the atomic memset
can be shortened at the beginning, if they partially overwritten
by later stores.
Reviewers: mkazantsev, skatkov, apilipenko, efriedma, rsmith, spatel, filcab, sanjoy
Reviewed By: efriedma
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D45584
llvm-svn: 331991
Fixes bug https://bugs.llvm.org/show_bug.cgi?id=37339.
InlineAsm is only uniqued if the FunctionTypes are exactly the
same, while cmpTypes() for example considers all pointer types
in the default address space to be the same. For this reason
the end of cmpInlineAsm() can be reached.
This patch replaces the unreachable assertion with a check that
the function types are not identical.
Differential Revision: https://reviews.llvm.org/D46495
Reviewers: jfb
llvm-svn: 331990
Put in a conservatively correct estimate for now. Avoids miscompiling
clang in FDO mode. This is really tricky to trigger in reality as
basically all interesting cases will be folded away by computeKnownBits
earlier, I was unable to find a reasonably small test case.
llvm-svn: 331975
This is a follow-up to D45986. As suggested there, we should match the "all-bits-set"
pattern in addition to "any-bits-set".
This was a little more complicated than I thought it would be initially because the
"and 1" instruction can be anywhere in the chain. Hopefully, the code comments make
that logic understandable, but if you see a way to simplify or improve that, it's
most appreciated.
This transforms patterns that emerge from bitfield tests as seen in PR37098:
https://bugs.llvm.org/show_bug.cgi?id=37098
I think it would also help reduce the large test from:
D46336
D46595
but we need something to reassociate that case to the forms we're expecting here first.
Differential Revision: https://reviews.llvm.org/D46649
llvm-svn: 331937
The previous handling for guard widening in InstCombine was extremely restrictive. In particular, it didn't handle the common case where we had two guards separated by a single icmp. Handle this by scanning through a small fixed window of instructions to find the next guard if needed.
Differential Revision: https://reviews.llvm.org/D46203
llvm-svn: 331935
This is safe as long as the udiv is not exact. The pattern is not common in
C++ code, but comes up all the time in code generated by XLA's GPU backend.
Differential Revision: https://reviews.llvm.org/D46647
llvm-svn: 331933
Summary:
MergedLoadStoreMotion::mergeStores is using some heuristics
to limit the amount of stores that it tries to sink (see
MagicCompileTimeControl in MergedLoadStoreMotion.cpp). The
heuristic involves counting the number of instructions in
one of the basic blocks that is part of the transformation.
We now ignore dbg intrinsics when counting instruction for
the MagicCompileTimeControl heuristic. This to make sure that
the amount of stores that are sunk doesn't depend on the amount
of debug information (if -g is used or not).
Reviewers: Gerolf, davide, majnemer
Reviewed By: davide
Subscribers: dberlin, bjope, aprantl, JDevlieghere, llvm-commits
Differential Revision: https://reviews.llvm.org/D46600
llvm-svn: 331852
In order to set breakpoints on labels and list source code around
labels, we need collect debug information for labels, i.e., label
name, the function label belong, line number in the file, and the
address label located. In order to keep these information in LLVM
IR and to allow backend to generate debug information correctly.
We create a new kind of metadata for labels, DILabel. The format
of DILabel is
!DILabel(scope: !1, name: "foo", file: !2, line: 3)
We hope to keep debug information as much as possible even the
code is optimized. So, we create a new kind of intrinsic for label
metadata to avoid the metadata is eliminated with basic block.
The intrinsic will keep existing if we keep it from optimized out.
The format of the intrinsic is
llvm.dbg.label(metadata !1)
It has only one argument, that is the DILabel metadata. The
intrinsic will follow the label immediately. Backend could get the
label metadata through the intrinsic's parameter.
We also create DIBuilder API for labels to be used by Frontend.
Frontend could use createLabel() to allocate DILabel objects, and use
insertLabel() to insert llvm.dbg.label intrinsic in LLVM IR.
Differential Revision: https://reviews.llvm.org/D45024
Patch by Hsiangkai Wang.
llvm-svn: 331841
Summary:
The current LowerInvoke pass cannot handle invoke instructions with a
funclet bundle operand. The order of operands for an invoke instruction
is {call arguments, callee, funclet operand (if any), normal dest,
unwind dest}. The current code assumes there is no funclet operand and
incorrectly includes a funclet operand into call arguments.
Reviewers: rnk
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D46242
llvm-svn: 331832
We enter MergeBlockIntoPredecessor with a block looking like this:
for.inc.us-lcssa: ; preds = %cond.end
%k.1.lcssa.ph = phi i32 [ %conv15, %cond.end ]
%t.3.lcssa.ph = phi i32 [ %k.1.lcssa.ph, %cond.end ]
br label %for.inc, !dbg !66
[note the first arg of the PHI being a PHI].
FoldSingleEntryPHINodes gets rid of both PHIs (calling, eraseFromParent).
But right before we call the function, we push into IncomingValues the
only argument of the PHIs, and shortly after we try to iterate over
something which has been invalidated before :(
The fix its not trying to remove PHIs which have an incoming value
coming from the same BB we're looking at.
Fixes PR37300 and rdar://problem/39910460
Differential Revision: https://reviews.llvm.org/D46568
llvm-svn: 331824
Summary:
Broadcast code generation emitted instructions in pre-header, while the instruction they are dependent on in the vector loop body.
This resulted in an IL verification error ---- value used before defined.
Reviewers: rengolin, fhahn, hfinkel
Reviewed By: rengolin, fhahn
Subscribers: dcaballe, Ka-Ka, llvm-commits
Differential Revision: https://reviews.llvm.org/D46302
llvm-svn: 331799
Summary:
In formLCSSAForInstructions we speculatively add new PHI
nodes, that sometimes ends up without having any uses. It
has been discovered that sometimes an added PHI node can
appear as being unused in one iteration of the Worklist,
although it can end up being used by a PHI node added in
a later iteration. We now check, a second time, that the
PHI node still is unused before we remove it. This avoids
an assert about "Trying to remove a phi with uses." for the
added test case.
Reviewers: davide, mzolotukhin, mattd, dberlin
Reviewed By: mzolotukhin, dberlin
Subscribers: dberlin, mzolotukhin, davide, bjope, uabelho, llvm-commits
Differential Revision: https://reviews.llvm.org/D46422
llvm-svn: 331741
Summary: Makes this consistent with the old PM.
Reviewers: eraman
Subscribers: mehdi_amini, llvm-commits
Differential Revision: https://reviews.llvm.org/D46526
llvm-svn: 331709
to be needed: jump table sections are created with .cfi.jumptable suffix. With
this change each jump table is placed in a separate section, which allows the
linker to re-order them.
Differential Revision: https://reviews.llvm.org/D46537
llvm-svn: 331680
whitequark