Summary:
Expand the print-memoryssa and print<memoryssa> passes with a new hidden
option -cfg-dot-mssa that names a file. When set, a dot-cfg style file
will be generated into the named file with the memoryssa comments retained
and those blocks containing them shown in light pink. The option does
nothing in isolation.
Author: Jamie Schmeiser <schmeise@ca.ibm.com>
Reviewed By: asbirlea (Alina Sbirlea), dblaikie (David Blaikie)
Differential Revision: https://reviews.llvm.org/D90638
The fshl and fshr intrinsics are defined to modulo their shift amount by the bitwidth of one of their inputs. The FSR/FSL instructions read one extra bit from the shift amount. If that bit is set the inputs are swapped. In order to preserve the semantics of the llvm intrinsics we need to make sure that the extra bit isn't set. DAG combine or instcombine may have removed any mask that was originally present.
We could be smarter here and try to use computeKnownBits to check if the bit is known zero, but wanted to start with correctness.
Differential Revision: https://reviews.llvm.org/D90905
Summary:
Add an option -print-before-changed that modifies the print-changed
behaviour so that it prints the IR before a pass that changed it in
addition to printing the IR after the pass. Note that the option
does nothing in isolation. The filtering options work as expected.
Lit tests are included.
Author: Jamie Schmeiser <schmeise@ca.ibm.com>
Reviewed By: aeubanks (Arthur Eubanks)
Differential Revision: https://reviews.llvm.org/D88757
Summary:
Refactor SinkAdHoistLICMFlags from a struct to a class with accessors and constructors to allow other
classes to construct flags with meaningful defaults while not exposing LICM internal details.
Author: Jamie Schmeiser <schmeise@ca.ibm.com>
Reviewed By: asbirlea (Alina Sbirlea)
Differential Revision: https://reviews.llvm.org/D90482
Of course there was something missing, in this case a check that the def
of the count register we are adding to a t2DoLoopStartTP would dominate
the insertion point.
In the future, when we remove some of these COPY's in between, the
t2DoLoopStartTP will always become the last instruction in the block,
preventing this from happening. In the meantime we need to check they
are created in a sensible order.
Differential Revision: https://reviews.llvm.org/D91287
This is a follow-up for D70378 (Cover usage of LLD as a library).
While debugging an intermittent failure on a bot, I recalled this scenario which
causes the issue:
1.When executing lld/test/ELF/invalid/symtab-sh-info.s L45, we reach
lld:🧝:Obj-File::ObjFile() which goes straight into its base ELFFileBase(),
then ELFFileBase::init().
2.At that point fatal() is thrown in lld/ELF/InputFiles.cpp L381, leaving a
half-initialized ObjFile instance.
3.We then end up in lld::exitLld() and since we are running with LLD_IN_TEST, we
hapily restore the control flow to CrashRecoveryContext::RunSafely() then back
in lld::safeLldMain().
4.Before this patch, we called errorHandler().reset() just after, and this
attempted to reset the associated SpecificAlloc<ObjFile<ELF64LE>>. That tried
to free the half-initialized ObjFile instance, and more precisely its
ObjFile::dwarf member.
Sometimes that worked, sometimes it failed and was catched by the
CrashRecoveryContext. This scenario was the reason we called
errorHandler().reset() through a CrashRecoveryContext.
But in some rare cases, the above repro somehow corrupted the heap, creating a
stack overflow. When the CrashRecoveryContext's filter (that is,
__except (ExceptionFilter(GetExceptionInformation()))) tried to handle the
exception, it crashed again since the stack was exhausted -- and that took the
whole application down. That is the issue seen on the bot. Locally it happens
about 1 times out of 15.
Now this situation can happen anywhere in LLD. Since catching stack overflows is
not a reliable scenario ATM when using CrashRecoveryContext, we're now
preventing further re-entrance when such failures occur, by signaling
lld::SafeReturn::canRunAgain=false. When running with LLD_IN_TEST=2 (or above),
only one iteration will be executed, instead of two.
Differential Revision: https://reviews.llvm.org/D88348
Change the default type of v64 register class from v512i32 to v256f64.
Add a regression test also.
Reviewed By: simoll
Differential Revision: https://reviews.llvm.org/D91301
When passing SVE types as arguments to function calls we can run
out of hardware SVE registers. This is normally fine, since we
switch to an indirect mode where we pass a pointer to a SVE stack
object in a GPR. However, if we switch over part-way through
processing a SVE tuple then part of it will be in registers and
the other part will be on the stack.
I've fixed this by ensuring that:
1. When we don't have enough registers to allocate the whole block
we mark any remaining SVE registers temporarily as allocated.
2. We temporarily remove the InConsecutiveRegs flags from the last
tuple part argument and reinvoke the autogenerated calling
convention handler. Doing this prevents the code from entering
an infinite recursion and, in combination with 1), ensures we
switch over to the Indirect mode.
3. After allocating a GPR register for the pointer to the tuple we
then deallocate any SVE registers we marked as allocated in 1).
We also set the InConsecutiveRegs flags back how they were before.
4. I've changed the AArch64ISelLowering LowerCALL and
LowerFormalArguments functions to detect the start of a tuple,
which involves allocating a single stack object and doing the
correct numbers of legal loads and stores.
Differential Revision: https://reviews.llvm.org/D90219
A piece of logic of `isLoopInvariantExitCondDuringFirstIterations` is actually
a generalized predicate monotonicity check. This patch moves it into the
corresponding method and generalizes it a bit.
Differential Revision: https://reviews.llvm.org/D90395
Reviewed By: apilipenko
Sometimes the an instruction we are trying to widen is used by the IV
(which means the instruction is the IV increment). Currently this may
prevent its widening. We should ignore such user because it will be
dead once the transform is done anyways.
Differential Revision: https://reviews.llvm.org/D90920
Reviewed By: fhahn
In the existing logic, for a given alloca, as long as its pointer value is stored into another location, it's considered as escaped.
This is a bit too conservative. Specifically, in non-optimized build mode, it's often to have patterns of code that first store an alloca somewhere and then load it right away.
These used should be handled without conservatively marking them escaped.
This patch tracks how the memory location where an alloca pointer is stored into is being used. As long as we only try to load from that location and nothing else, we can still
consider the original alloca not escaping and keep it on the stack instead of putting it on the frame.
Differential Revision: https://reviews.llvm.org/D91305
InstCombine canonicalizes 'sub nuw' instructions to 'add' without the
`nuw` flag. The typical case where we see it is decrementing induction
variables. For them, IndVars fails to prove that it's legal to widen them,
and inserts unprofitable `zext`'s.
This patch adds recognition of such pattern using SCEV.
Differential Revision: https://reviews.llvm.org/D89550
Reviewed By: fhahn, skatkov
We need to be able to call function pointers. Inline the dispatch
function.
Also inline the context projection function.
Transfer debug locations from the suspend point to the inlined functions.
Use the function argument index instead of the function argument in
coro.id.async. This solves any spurious use issues.
Coerce the arguments of the tail call function at a suspend point. The LLVM
optimizer seems to drop casts leading to a vararg intrinsic.
rdar://70097093
Differential Revision: https://reviews.llvm.org/D91098
Some targets may add required passes via
TargetMachine::registerPassBuilderCallbacks(). We need to run those even
under -O0. As an example, BPFTargetMachine adds
BPFAbstractMemberAccessPass, a required pass.
This also allows us to clean up BackendUtil.cpp (and out-of-tree Rust
usage of the NPM) by allowing us to share added passes like coroutines
and sanitizers between -O0 and other optimization levels.
Since callbacks may end up not adding passes, we need to check if the
pass managers are empty before adding them, so PassManager now has an
isEmpty() function. For example, polly adds callbacks but doesn't always
add passes in those callbacks, so this is necessary to keep
-debug-pass-manager tests' output from changing depending on if polly is
enabled or not.
Tests are a continuation of those added in
https://reviews.llvm.org/D89083.
Reviewed By: asbirlea, Meinersbur
Differential Revision: https://reviews.llvm.org/D89158
Previously the inliner did a bit of a hack by adding ref edges for all
new edges introduced by performing an inline before calling
updateCGAndAnalysisManagerForPass(). This was because
updateCGAndAnalysisManagerForPass() didn't handle new non-trivial call
edges.
This adds handling of non-trivial call edges to
updateCGAndAnalysisManagerForPass(). The inliner called
updateCGAndAnalysisManagerForFunctionPass() since it was handling adding
newly introduced edges (so updateCGAndAnalysisManagerForPass() would
only have to handle promotion), but now it needs to call
updateCGAndAnalysisManagerForCGSCCPass() since
updateCGAndAnalysisManagerForPass() is now handling the new call edges
and function passes cannot add new edges.
We follow the previous path of adding trivial ref edges then letting promotion
handle changing the ref edges to call edges and the CGSCC updates. So
this still does not allow adding call edges that result in an addition
of a non-trivial ref edge.
This is in preparation for better detecting devirtualization. Previously
since the inliner itself would add ref edges,
updateCGAndAnalysisManagerForPass() would think that promotion and thus
devirtualization had happened after any sort of inlining.
Reviewed By: asbirlea
Differential Revision: https://reviews.llvm.org/D91046
When there is full fp16 support, there is no reason to widen 16-bit
G_FCONSTANTs to 32 bits. Mark them as legal in this case.
Also, we currently import a pattern for materializing a 16-bit 0.0.
Add a testcase showing we select it.
(All other 16-bit G_FCONSTANTS are not yet selected.)
Differential Revision: https://reviews.llvm.org/D89164
Before the change, DFSan always does the propagation. W/o
origin tracking, it is harder to understand such flows. After
the change, the flag is off by default.
Reviewed-by: morehouse
Differential Revision: https://reviews.llvm.org/D91234
This reverts commit 09248a5d25bb1c9f357247fa3da8fbe4470e9c67.
Some builds are broken. I suspect a `static constexpr` in a class missing a
definition out of class (required pre-c++17).
xnu coredumps include an LC_IDENT load command. It's helpful to be able
to just ignore these. IIUC an interested client can grab the identifier
using the MachOObjectFile::load_commands() API.
The status quo is that llvm bails out when it finds an LC_IDENT because
the command is obsolete (see isLoadCommandObsolete).
Differential Revision: https://reviews.llvm.org/D91221
We were creating RISCVISD::SELECT_CC nodes with Glue output that was never being used, and the tablegen SDNode had the SDNPInGlue flag instead of the SDNPOutGlue flag.
Since we don't seem to need the Glue just get rid of it from both places.
Differential Revision: https://reviews.llvm.org/D91199
The manual selection code for add/sub was not checking if it was possible to
fold in shifts + extends (the *rx opcode variants).
As a result, we could never select things like
```
cmp x1, w0, uxtw #2
```
Because we don't import any patterns for compares.
This adds support for the arithmetic shifted register forms and updates tests
for instructions selected using `emitADD`, `emitADDS`, and `emitSUBS`.
This is a 0.1% geomean code size improvement on SPECINT2000 at -Os.
Differential Revision: https://reviews.llvm.org/D91207
Alternative to D74755. sectionWithinSegment() treats an empty section as having
a size of 1. Due to the rule, an empty .tdata will not be attributed to an
empty PT_TLS. (The empty p_align=64 PT_TLS is for Android Bionic's TCB
compatibility (ELF-TLS). See https://reviews.llvm.org/D62055#1507426)
Currently --only-keep-debug will not layout a segment with no section
(layoutSegmentsForOnlyKeepDebug()), thus p_offset of PT_TLS can go past the end
of the file. The strange p_offset can trigger validation errors for subsequent
tools, e.g. llvm-objcopy errors when reading back the separate debug file
(readProgramHeaders()).
This patch places such an empty segment according to its parent segment. This
special cases works for the empty PT_TLS used in Android. For a non-empty
segment, it should have at least one non-empty section and will be handled by
the normal code. Note, p_memsz PT_LOAD is rejected by both Linux and FreeBSD.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D90897
Previously, we only handled negative arithmetic immediates in the imported
selector code.
Since we don't import code for, say, compares, we were missing opportunities
for things like
```
%cst:gpr(s64) = G_CONSTANT i64 -10
%cmp:gpr(s32) = G_ICMP intpred(eq), %reg0(s64), %cst
->
%adds = ADDSXri %reg0, 10, 0, implicit-def $nzcv
%cmp = CSINCWr $wzr, $wzr, 1, implicit $nzcv
```
Instead, we would have to materialize the constant and emit a SUBS.
This adds support for selection like above for SUB, SUBS, ADD, and ADDS.
This is a 0.1% geomean code size improvement on SPECINT2000 at -Os.
Differential Revision: https://reviews.llvm.org/D91108
I was trying to add .cfi_ annotations to assembly code in the FreeBSD
kernel and changed a macro that then resulted in incorrectly nested
directives. However, clang's diagnostics said the error was happening at
<unknown>:0. This addresses one of the TODOs added in D51695.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D89787
This broke both Firefox and Chromium (PR47905) due to what seems like dllimport
function not being handled correctly.
> This patch adds support for creating Guard Address-Taken IAT Entry Tables (.giats$y sections) in object files, matching the behavior of MSVC. These contain lists of address-taken imported functions, which are used by the linker to create the final GIATS table.
> Additionally, if any DLLs are delay-loaded, the linker must look through the .giats tables and add the respective load thunks of address-taken imports to the GFIDS table, as these are also valid call targets.
>
> Reviewed By: rnk
>
> Differential Revision: https://reviews.llvm.org/D87544
This reverts commit cfd8481da1adba1952e0f6ecd00440986e49a946.
