Depending on who you ask, PGO grants a 15%-25% improvement in build
times when using clang. Sadly, hooking everything up properly to
generate a profile and apply it to clang isn't always straightforward.
This script (and the accompanying docs) aim to make this process easier;
ideally, a single invocation of the given script.
In terms of testing, I've got a cronjob on my Debian box that's meant to
run this a few times per week, and I tried manually running it on a puny
Gentoo box I have (four whole Atom cores!). Nothing obviously broke.
¯\_(ツ)_/¯
I don't know if we have a Python style guide, so I just shoved this
through yapf with all the defaults on.
Finally, though the focus is clang at the moment, the hope is that this
is easily applicable to other LLVM-y tools with minimal effort (e.g.
lld, opt, ...). Hence, this lives in llvm/utils and tries to be somewhat
ambiguous about naming.
Differential Revision: https://reviews.llvm.org/D53598
llvm-svn: 345427
Summary:
The main challenge here is that X86InstrInfo::AnalyzeBranch doesn't
understand the way we're using a CALL instruction as a branch, so we
can't list the CallTarget MBB as a successor of the entry block. If we
don't list it as a successor, then the AsmPrinter doesn't print a label
for the MBB.
Fix the issue by inserting our own label at the beginning of the call
target block. We can rely on the AsmPrinter to always emit it, even
though the block appears to be unreachable, but address-taken.
Fixes PR38391.
Reviewers: thegameg, chandlerc, echristo
Subscribers: hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D53653
llvm-svn: 345426
The "dead" markings allow existing target-independent optimizations,
like MachineSink, to trigger more frequently. The CPSR defs would have
eventually been marked dead by LiveVariables, so this only affects
optimizations before regalloc.
The ARMBaseInstrInfo.cpp change is fixing a bug which is only visible
with this change: the transform adds a use to an otherwise dead def
of CPSR. This is covered by existing regression tests.
thumb2-tbh.ll breaks for Thumb1 due to MachineLICM changing the
generated code; I'll fix it in D53452.
Differential Revision: https://reviews.llvm.org/D53453
llvm-svn: 345420
Currently, for this node:
vector int test(int a, int b, int c, int d) {
return (vector int) { a, b, c, d };
}
we get this on Power9:
mtvsrdd 34, 5, 3
mtvsrdd 35, 6, 4
vmrgow 2, 3, 2
and this on Power8:
mtvsrwz 0, 3
mtvsrwz 1, 5
mtvsrwz 2, 4
mtvsrwz 3, 6
xxmrghd 34, 1, 0
xxmrghd 35, 3, 2
vmrgow 2, 3, 2
This can be improved to this on LE Power9:
rldimi 3, 4, 32, 0
rldimi 5, 6, 32, 0
mtvsrdd 34, 5, 3
and this on LE Power8
rldimi 3, 4, 32, 0
rldimi 5, 6, 32, 0
mtvsrd 34, 3
mtvsrd 35, 5
xxpermdi 34, 35, 34, 0
This patch updates the TD pattern to generate the optimized sequence for both
Power8 and Power9 on LE and BE.
Differential Revision: https://reviews.llvm.org/D53494
llvm-svn: 345414
Summary:
The visitICmp analysis function would record compares of pointer types, as size 0. This causes the resulting memcmp() call to have the wrong total size.
Found with "self-build" of clang/LLVM on Windows.
Reviewers: christylee, trentxintong, courbet
Reviewed By: courbet
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D53536
llvm-svn: 345413
Inheriting constructors from std::pair caused clang-3.8 to treat some DenseMap
initializer_list constructor calls as ambiguous, which broke several bots. This
commit explicitly defines DenseMapPair's constructos to work around the issue.
https://reviews.llvm.org/D53726
llvm-svn: 345411
These promotions add additional bitcasts to the SelectionDAG that can pessimize computeKnownBits/computeNumSignBits. It also seems to interfere with broadcast formation.
This patch removes the promotion and adds isel patterns instead.
The increased table size is more than I would like, but hopefully we can find some canonicalizations or other tricks to start pruning out patterns going forward.
Differential Revision: https://reviews.llvm.org/D53268
llvm-svn: 345408
This is a narrow fix for 1 of the problems mentioned in PR27780:
https://bugs.llvm.org/show_bug.cgi?id=27780
I looked at more general solutions, but it's a mess. We canonicalize shuffle masks
based on the number of elements accessed from each operand, and that's not optional.
If you remove that, we'll crash because we fail to match isel patterns. So I'm
waiting until we're sure that we have blendvb with constant condition and then
commuting based on the load potential. Other cases like blend-with-immediate are
already handled elsewhere, so this is probably not a common problem anyway.
I didn't use "MayFoldLoad" because that checks for one-use and in these cases, we've
screwed that up by creating a temporary PSHUFB using these operands that we're counting
on to be killed later. Undoing that didn't look like a simple task because it's
intertwined with determining if we actually use both operands of the shuffle or not.a
Differential Revision: https://reviews.llvm.org/D53737
llvm-svn: 345390
This patch adds support of `llvm.experimental.guard` intrinsics to non-trivial
simple loop unswitching. These intrinsics represent implicit control flow which
has pretty much the same semantics as usual conditional branches. The
algorithm of dealing with them is following:
- Consider guards as unswitching candidates;
- If a guard is considered the best candidate, turn it into a branch;
- Apply normal unswitching algorithm on this branch.
The patch has no compile time effect on code that does not contain any guards.
Differential Revision: https://reviews.llvm.org/D53744
Reviewed By: chandlerc
llvm-svn: 345387
While working on FileCheck producing better diagnostics in D53710, I noticed
that our test case is broken in a few different ways. The test was running, but
results were not checked as prefix CHECK-COMMON wasn't defined (which is what
FileCheck should warn about). Also, the output was different in 2 cases because
of recent changes in ARMCodeGenPrepare.
Differential Revision: https://reviews.llvm.org/D53746
llvm-svn: 345386
ADDLIB is called to add the contents of an archive to another archive.
Previously this was only accessible through the use of an MRI script.
With the use of a new "L" modifier, archive files can treated in the
manner above when using quick append.
llvm-svn: 345383
AMDGPU currently only supports direct calls, but at lower optimisation levels it
fails to lower statically direct calls which appear indirect due to a bitcast.
Add a pass to visit all CallSites and use CallPromotionUtils to "devirtualize"
calls.
Differential Revision: https://reviews.llvm.org/D52741
llvm-svn: 345382
.debug_loclists is the DWARF 5 version of the .debug_loc.
With that patch, it will be emitted when DWARF 5 is used.
Differential revision: https://reviews.llvm.org/D53365
llvm-svn: 345377
We should be able to make all relevant checks before we actually start the non-trivial
unswitching, so that we could guarantee that once we have started the transform,
it will always succeed.
Reviewed By: chandlerc
Differential Revision: https://reviews.llvm.org/D53747
llvm-svn: 345375
Change a \t to spaces
Change some zero-filling memcpy to aggregate initialization
Delete redundant ArchiveName.clear() after declaration
llvm-svn: 345367
For both operands are bool, short, int, long, long long, add the following optimization.
1. 0-x == y --> x+y ==0
2. 0-x != y --> x+y != 0
Review: nemanjai
Differential Revision: https://reviews.llvm.org/D53360
llvm-svn: 345366
For both operands are bool, short, int, long, long long, add the following optimization test case.
1. 0-x == y --> x+y ==0
2. 0-x != y --> x+y != 0
Review: nemanjai
Differential Revision: https://reviews.llvm.org/D53358
llvm-svn: 345365
Currently, the regular expression that matches the lines of assembly for PPC LE
(ELFv2) does not work for the assembly for BE (ELFv1). This patch fixes it.
Differential revision: https://reviews.llvm.org/D53059
llvm-svn: 345363
At present a v2i16 -> v2f64 convert is implemented by extracts to scalar,
scalar converts, and merge back into a vector. Use vector converts instead,
with the int data permuted into the proper position and extended if necessary.
Patch by RolandF.
Differential revision: https://reviews.llvm.org/D53346
llvm-svn: 345361
For both operands are bool, short, int, long, long long, add the following optimization test case.
1. 0-x == y --> x+y ==0
2. 0-x != y --> x+y != 0
Review: nemanjai
Differential Revision: https://reviews.llvm.org/D53358
llvm-svn: 345357
Summary:
This patch makes the dominatortree recalculate when applying updates with the size of the update vector larger than a threshold. Directly applying updates is usually slower than recalculating the whole domtree in this case. This patch fixes an issue which causes JT running slowly on some inputs.
In bug 37929, the dominator tree is trying to apply 19,000+ updates several times, which takes several minutes.
After this patch, the time used by DT.applyUpdates:
| Input | Before (s) | After (s) | Speedup |
| the 2nd Reproducer in 37929 | 297 | 0.15 | 1980x |
| clang-5.0.0.0.bc | 9.7 | 4.3 | 2.26x |
| clang-5.0.0.4.bc | 11.6 | 2.6 | 4.46x |
Reviewers: kuhar, brzycki, trentxintong, davide, dmgreen, grosser
Reviewed By: kuhar, brzycki
Subscribers: kristina, llvm-commits
Differential Revision: https://reviews.llvm.org/D53245
llvm-svn: 345353
SystemZAsmParser can now handle -debug by printing the operands neatly to the
output stream. Before this patch this lead to an llvm_unreachable().
It seems that now '-mllvm -debug' does not cause any crashes anywhere (at
least not on SPEC).
Review: Ulrich Weigand
https://reviews.llvm.org/D53328
llvm-svn: 345349
In order to print the IR slot number for the memory operand, the DAG pointer
must be passed to SDNode::dump().
The isel-debug.ll test updated to also check for the IR Value reference being
printed correctly.
Review: Ulrich Weigand
https://reviews.llvm.org/D53333
llvm-svn: 345347
Summary:
This adds support for LSDA (exception table) generation for wasm EH.
Wasm EH mostly follows the structure of Itanium-style exception tables,
with one exception: a call site table entry in wasm EH corresponds to
not a call site but a landing pad.
In wasm EH, the VM is responsible for stack unwinding. After an
exception occurs and the stack is unwound, the control flow is
transferred to wasm 'catch' instruction by the VM, after which the
personality function is called from the compiler-generated code. (Refer
to WasmEHPrepare pass for more information on this part.)
This patch:
- Changes wasm.landingpad.index intrinsic to take a token argument, to
make this 1:1 match with a catchpad instruction
- Stores landingpad index info and catch type info MachineFunction in
before instruction selection
- Lowers wasm.lsda intrinsic to an MCSymbol pointing to the start of an
exception table
- Adds WasmException class with overridden methods for table generation
- Adds support for LSDA section in Wasm object writer
Reviewers: dschuff, sbc100, rnk
Subscribers: mgorny, jgravelle-google, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D52748
llvm-svn: 345345
Handle the case where getCurrentFunction() returns nullptr by passing -1 to
printIRSlotNumber(). This will result in <badref> being printed instead of an
assertion failure.
Review: Francis Visoiu Mistrih
https://reviews.llvm.org/D53333
llvm-svn: 345342
Add LLVM intrinsics for the ARMv8.2-A FP16FML vector-form instructions. Add a
DAG pattern to define the indexed-form intrinsics in terms of the vector-form
ones, similarly to how the Dot Product intrinsics were implemented.
Based on a patch by Gao Yiling.
Differential Revision: https://reviews.llvm.org/D53632
llvm-svn: 345337
