Summary:
This patch adds a LLVM_ENABLE_GISEL_COV which, like LLVM_ENABLE_DAGISEL_COV,
causes TableGen to instrument the generated table to collect rule coverage
information. However, LLVM_ENABLE_GISEL_COV goes a bit further than
LLVM_ENABLE_DAGISEL_COV. The information is written to files
(${CMAKE_BINARY_DIR}/gisel-coverage-* by default). These files can then be
concatenated into ${LLVM_GISEL_COV_PREFIX}-all after which TableGen will
read this information and use it to emit warnings about untested rules.

This technique could also be used by SelectionDAG and can be further
extended to detect hot rules and give them priority over colder rules.

Usage:
* Enable LLVM_ENABLE_GISEL_COV in CMake
* Build the compiler and run some tests
* cat gisel-coverage-[0-9]* > gisel-coverage-all
* Delete lib/Target/*/*GenGlobalISel.inc*
* Build the compiler

Known issues:
* ${LLVM_GISEL_COV_PREFIX}-all must be generated as a manual
  step due to a lack of a portable 'cat' command. It should be the
  concatenation of all ${LLVM_GISEL_COV_PREFIX}-[0-9]* files.
* There's no mechanism to discard coverage information when the ruleset
  changes

Depends on D39742

Reviewers: ab, qcolombet, t.p.northover, aditya_nandakumar, rovka

Reviewed By: rovka

Subscribers: vsk, arsenm, nhaehnle, mgorny, kristof.beyls, javed.absar, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D39747

llvm-svn: 318356

llvm-svn: 318355

std::distance returns ptrdiff_t which is signed. 64-bit builds don't notice because type promotion widens the unsigned first.

llvm-svn: 318354

Due to integer precision, we might have numerator greater than denominator in
the branch probability scaling. Add a check to prevent this from happening.

llvm-svn: 318353

Summary:
Make it possible to feed runtime information back to tablegen to enable
profile-guided tablegen-eration, detection of untested tablegen definitions, etc.

Being a cross-compiler by nature, LLVM will potentially collect data for multiple
architectures (e.g. when running 'ninja check'). We therefore need a way for
TableGen to figure out what data applies to the backend it is generating at the
time. This patch achieves that by including the name of the 'def X : Target ...'
for the backend in the TargetRegistry.

Reviewers: qcolombet

Reviewed By: qcolombet

Subscribers: jholewinski, arsenm, jyknight, aditya_nandakumar, sdardis, nemanjai, ab, nhaehnle, t.p.northover, javed.absar, qcolombet, llvm-commits, fedor.sergeev

Differential Revision: https://reviews.llvm.org/D39742

llvm-svn: 318352

Fix the modeling of FP stores.

llvm-svn: 318351

[GISel][NFC]: Move getOpcodeDef from the LegalizationArtifactCombiner into GlobalISel/Utils for use elsewhere

llvm-svn: 318350

Summary:
lsan_preinit.cc is meant to be linked into executable and calls
lsan_init from .preinit_array section. But if liblsan is a shared library,
then this doesn't work, because the symbol is not exported. This patch fixes
that. The counterparts like asan_init or __tsan_init already do have
SANITIZER_INTERFACE_ATTRIBUTE.

Committing on behalf of jakubjelinek.

Reviewers: alekseyshl, kcc

Subscribers: llvm-commits

Differential revision: https://reviews.llvm.org/D39889

llvm-svn: 318349

llvm-svn: 318348

llvm-svn: 318347

llvm-svn: 318345

A first step toward removing the repetition of
features/CPU info in the x86 target info, this
patch pulls all the processor information out into
its own .def file.

Differential Revision: https://reviews.llvm.org/D40093

llvm-svn: 318343

This might be the root cause of PR35295:
https://bugs.llvm.org/show_bug.cgi?id=35295

llvm-svn: 318342

[AST, Sema] Fix some Clang-tidy modernize and Include What You Use warnings; other minor fixes (NFC).

llvm-svn: 318341

Use VOP3 add/addc like usual.

This has some tradeoffs. Inline immediates fold
a little better, but other constants are worse off.
SIShrinkInstructions could be made smarter to handle
these cases.

This allows us to avoid selecting scalar adds where we
need to track the carry in scc and replace its users.
This makes it easier to use the carryless VALU adds.

llvm-svn: 318340

llvm-svn: 318339

Remove -switch-peel-threshold=100 and update the expected results in test10
in cfg-stackify.ll.

llvm-svn: 318338

(Clearly this is not a permanent solution)

llvm-svn: 318337

llvm-svn: 318336

Move remaining inline matching of instructions of some optimizations into
separate functions, like in the other optimizations.  Otherwise, NFC.

Differential revision: https://reviews.llvm.org/D40090

llvm-svn: 318335

This moves the file handling out of DwarfLinker.cpp.

This fixes what is at least an oddity if not a bug. DwarfLinker.cpp
was using ToolOutputFile, which uses RemoveFileOnSignal. The issue is
that dsymutil.cpp uses that too. It is now clear from the interface
that only dsymutil.cpp is responsible for creating and deleting files.

llvm-svn: 318334

llvm-svn: 318331

llvm-svn: 318330

llvm-svn: 318329

More of P0600 - '[[nodiscard]] in the Library' mark empty() as nodiscard in string, string_view, and the free function std::empty(). Removed tabs from <string_view>, which is why the diff is so big.

llvm-svn: 318328

llvm-svn: 318327

Differential Revision: D39221

llvm-svn: 318325

The original -O binary implementation just copied segment data from the
object and dumped it into a file. This doesn't take into account any
operations performed on objects such as section removal. GNU objcopy has
some specific behavior that we'd also like to respect. For instance
using -O binary and -j <some_section> will dump <some_section> to a
file. This change implements GNU objcopy style -O binary to as close of
an approximation as I can determine.

Differential Revision: https://reviews.llvm.org/D39713

llvm-svn: 318324

Note that one-use and shouldChangeType() are checked ahead of the switch.

Without the narrowing folds, we can produce inferior vector code as shown in PR35299:
https://bugs.llvm.org/show_bug.cgi?id=35299

llvm-svn: 318323

This requires a small change to TempFile: allowing a discard after a
failed keep.

With this the cache now handles signals and reuses a fd instead of
reopening the file.

llvm-svn: 318322

Implements TargetLowering callback 'mayBeEmittedAsTailCall' that enables
CodeGenPrepare to duplicate returns when they might enable a tail-call.

Differential Revision: https://reviews.llvm.org/D39777

llvm-svn: 318321

InstCombine salvages debug info for every instruction it erases from its
worklist, but it wasn't doing it during its initial DCE when populating
its worklist. This fixes that.

This should help improve availability of 'this' in optimized debug info
when casts are necessary.

llvm-svn: 318320

As noted in PR35299:
https://bugs.llvm.org/show_bug.cgi?id=35299
...this is likely the root cause for a mis-vectorization transform.

llvm-svn: 318319

Thanks to arsenm and davide for the suggestion!

llvm-svn: 318318

llvm-svn: 318317

llvm-svn: 318316

The number of 'built-in candidate' notes now varies since __float128 may
or may not be a candidate depending on the target.

llvm-svn: 318314

llvm-svn: 318313

Fix the modeling of loads and stores using the pre or post indexed
addressing modes.

llvm-svn: 318312

An output section can include elements from two input sections with
different sh_entsize. When that happens the output section itself
should not have a sh_entsize.

llvm-svn: 318311