Commit Graph

23 Commits

Author SHA1 Message Date
Nikita Popov 532dc62b90 [OpaquePtrs][Clang] Add -no-opaque-pointers to tests (NFC)
This adds -no-opaque-pointers to clang tests whose output will
change when opaque pointers are enabled by default. This is
intended to be part of the migration approach described in
https://discourse.llvm.org/t/enabling-opaque-pointers-by-default/61322/9.

The patch has been produced by replacing %clang_cc1 with
%clang_cc1 -no-opaque-pointers for tests that fail with opaque
pointers enabled. Worth noting that this doesn't cover all tests,
there's a remaining ~40 tests not using %clang_cc1 that will need
a followup change.

Differential Revision: https://reviews.llvm.org/D123115
2022-04-07 12:09:47 +02:00
Ellis Hoag de11de308b [InstrProf] Use i32 for GEP index from lowering llvm.instrprof.increment
The `llvm.instrprof.increment` intrinsic uses `i32` for the index. We should use this same type for the index into the GEP instructions.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D114268
2021-11-19 15:45:14 -08:00
Arthur Eubanks 5c31b8b94f Revert "Use uint64_t for branch weights instead of uint32_t"
This reverts commit 10f2a0d662.

More uint64_t overflows.
2020-10-31 00:25:32 -07:00
Arthur Eubanks 10f2a0d662 Use uint64_t for branch weights instead of uint32_t
CallInst::updateProfWeight() creates branch_weights with i64 instead of i32.
To be more consistent everywhere and remove lots of casts from uint64_t
to uint32_t, use i64 for branch_weights.

Reviewed By: davidxl

Differential Revision: https://reviews.llvm.org/D88609
2020-10-30 10:03:46 -07:00
Nico Weber 2a4e704c92 Revert "Use uint64_t for branch weights instead of uint32_t"
This reverts commit e5766f25c6.
Makes clang assert when building Chromium, see https://crbug.com/1142813
for a repro.
2020-10-27 09:26:21 -04:00
Arthur Eubanks e5766f25c6 Use uint64_t for branch weights instead of uint32_t
CallInst::updateProfWeight() creates branch_weights with i64 instead of i32.
To be more consistent everywhere and remove lots of casts from uint64_t
to uint32_t, use i64 for branch_weights.

Reviewed By: davidxl

Differential Revision: https://reviews.llvm.org/D88609
2020-10-26 20:24:04 -07:00
Vedant Kumar 6186971a4a [PGO] Detect more structural changes with the stable hash
Lifting from Bob Wilson's notes: The hash value that we compute and
store in PGO profile data to detect out-of-date profiles does not
include enough information. This means that many significant changes to
the source will not cause compiler warnings about the profile being out
of date, and worse, we may continue to use the outdated profile data to
make bad optimization decisions.  There is some tension here because
some source changes won't affect PGO and we don't want to invalidate the
profile unnecessarily.

This patch adds a new hashing scheme which is more sensitive to loop
nesting, conditions, and out-of-order control flow. Here are examples
which show snippets which get the same hash under the current scheme,
and different hashes under the new scheme:

Loop Nesting Example
--------------------

  // Snippet 1
  while (foo()) {
    while (bar()) {}
  }

  // Snippet 2
  while (foo()) {}
  while (bar()) {}

Condition Example
-----------------

  // Snippet 1
  if (foo())
    bar();
  baz();

  // Snippet 2
  if (foo())
    bar();
  else
    baz();

Out-of-order Control Flow Example
---------------------------------

  // Snippet 1
  while (foo()) {
    if (bar()) {}
    baz();
  }

  // Snippet 2
  while (foo()) {
    if (bar())
      continue;
    baz();
  }

In each of these cases, it's useful to differentiate between the
snippets because swapping their profiles gives bad optimization hints.

The new hashing scheme considers some logical operators in an effort to
detect more changes in conditions. This isn't a perfect scheme. E.g, it
does not produce the same hash for these equivalent snippets:

  // Snippet 1
  bool c = !a || b;
  if (d && e) {}

  // Snippet 2
  bool f = d && e;
  bool c = !a || b;
  if (f) {}

This would require an expensive data flow analysis. Short of that, the
new hashing scheme looks reasonably complete, based on a scan over the
statements we place counters on.

Profiles which use the old version of the PGO hash remain valid and can
be used without issue (there are tests in tree which check this).

rdar://17068282

Differential Revision: https://reviews.llvm.org/D39446

llvm-svn: 318229
2017-11-14 23:56:53 +00:00
Rong Xu 9c6f1538cc [PGO] Change profile use cc1 option to handle IR level profiles
This patch changes cc1 option for PGO profile use from
-fprofile-instr-use=<path> to -fprofile-instrument-use-path=<path>.
-fprofile-instr-use=<path> is now a driver only option.

In addition to decouple the cc1 option from the driver level option, this patch
also enables IR level profile use. cc1 option handling now reads the profile
header and sets CodeGenOpt ProfileUse (valid values are {None, Clang, LLVM}
-- this is a common enum for -fprofile-instrument={}, for the profile
instrumentation), and invoke the pipeline to enable the respective PGO use pass.

Reviewers: silvas, davidxl

Differential Revision: http://reviews.llvm.org/D17737

llvm-svn: 262515
2016-03-02 20:59:36 +00:00
Rong Xu 9837ef56b4 [PGO] cc1 option name change for profile instrumentation
This patch changes cc1 option -fprofile-instr-generate to an enum option
-fprofile-instrument={clang|none}. It also changes cc1 options
-fprofile-instr-generate= to -fprofile-instrument-path=.
The driver level option -fprofile-instr-generate and -fprofile-instr-generate=
remain intact. This change will pave the way to integrate new PGO
instrumentation in IR level.

Review: http://reviews.llvm.org/D16730
llvm-svn: 259811
2016-02-04 18:39:09 +00:00
Xinliang David Li ddbdb1e0be [PGO] make profile prefix even shorter and more readable
llvm-svn: 255587
2015-12-15 00:33:12 +00:00
Xinliang David Li 8608513b69 [PGO] Shorten profile symbol prefixes
(test case update)
Profile symbols have long prefixes which waste space and creating pressure for linker.
This patch shortens the prefixes to minimal length without losing verbosity.

Differential Revision: http://reviews.llvm.org/D15503

llvm-svn: 255576
2015-12-14 23:26:46 +00:00
Xinliang David Li aab1fd16bc [PGO] Stop using invalid char in instr variable names.
(This is part-2 of the patch of r255434 -- 
fixing test cases, second try)

llvm-svn: 255435
2015-12-12 17:28:37 +00:00
Xinliang David Li e1769ef559 [PGO] Revert r255366: solution incomplete, not handling lambda yet
llvm-svn: 255368
2015-12-11 20:23:12 +00:00
Xinliang David Li 871daea550 [PGO] Stop using invalid char in instr variable names.
(This is part-2 of the patch -- fixing test cases)

Before the patch, -fprofile-instr-generate compile will fail
if no integrated-as is specified when the file contains
any static functions (the -S output is also invalid).

This patch fixed the issue. With the change, the index format
version will be bumped up by 1. Backward compatibility is 
preserved with this change.

Differential Revision: http://reviews.llvm.org/D15243

llvm-svn: 255366
2015-12-11 19:53:35 +00:00
Justin Bogner e9fe0a298c InstrProf: Make profile variables private to reduce binary size overhead
When we instrument a program for profiling, we copy the linkage of an
instrumented function so that our datastructures merge in the same way
as the function. This avoids redundant copies for things like
linkonce, but ends up emitting names we never need to reference for
normal and internal symbols. Promoting internal and external linkage
to private for these variables reduces the size overhead of profiling
drastically.

llvm-svn: 232799
2015-03-20 06:34:38 +00:00
Duncan P. N. Exon Smith b3a66691f8 IR: Make metadata typeless in assembly, clang side
Match LLVM changes from r224257.

llvm-svn: 224259
2014-12-15 19:10:08 +00:00
Justin Bogner 111c6533c2 InstrProf: Use the same names for variables as we use in the profile
There's no need to use different names for the local variables than we
use in the profile itself, and it's a bit simpler and easier to debug
if we're consistent.

llvm-svn: 223173
2014-12-02 23:15:30 +00:00
Duncan P. N. Exon Smith 9121220804 InstrProf: Set profile data to visibility hidden
Shared objects are fairly broken for InstrProf right now -- a follow-up
commit in compiler-rt will fix the rest of this.

The main problem here is that at link time, profile data symbols in the
shared object might get used instead of symbols from the main
executable, creating invalid profile data sections.

<rdar://problem/16918688>

llvm-svn: 208939
2014-05-16 01:24:00 +00:00
Justin Bogner 534f14abe7 test: Use llvm-profdata merge in Profile tests
In preparation for using a binary format for instrumentation based
profiling, explicitly treat the test inputs as text and transform them
before running. This will allow us to leave the checked in files in
human readable format once the instrumentation format is binary.

No functional change.

llvm-svn: 206509
2014-04-17 22:49:06 +00:00
Bob Wilson 0ed74d9634 [PGO] Add simplified branch weights for Objective-C for-collection loops.
Conceptually one of these loops is just a while-loop, but the actual code-gen
is more complicated. We don't instrument all the different control flow edges
to get accurate counts for each conditional branch, nor do I think it makes
sense to do so. Instead, make the simplifying assumption that the loop behaves
like a while-loop. Use the same branch weights for the first check for an
empty collection as would be used for the back-edge of a while loop, and use
that same weighting for the innermost loop, ignoring the possibility that there
may be some extra code to go fetch more elements.

llvm-svn: 204767
2014-03-25 23:26:31 +00:00
Duncan P. N. Exon Smith a7807637bf PGO: Change runtime prefix from pgo to profile
These functions are in the profile runtime.  PGO comes later.

Unfortunately, there's only room for 16 characters in a Darwin section,
so use __llvm_prf_ instead of __llvm_profile_ for section names.

<rdar://problem/15943240>

llvm-svn: 204390
2014-03-20 20:00:41 +00:00
Duncan P. N. Exon Smith 2fe531cb07 PGO: Statically generate data structures
In instrumentation-based profiling, we need a set of data structures to
represent the counters.  Previously, these were built up during static
initialization.  Now, they're shoved into a specially-named section so
that they show up as an array.

As a consequence of the reorganizing symbols, instrumentation data
structures for linkonce functions are now correctly coalesced.

This is the first step in a larger project to minimize runtime overhead
and dependencies in instrumentation-based profilng.  The larger picture
includes removing all initialization overhead and making the dependency
on libc optional.

<rdar://problem/15943240>

llvm-svn: 204080
2014-03-17 21:18:30 +00:00
Justin Bogner 52a6a97d70 test: Give instrumentation based profiling tests their own directory
These tests are logically related, but they're spread about several
different CodeGen directories. Consolidate them in one place to make
them easier to manage.

llvm-svn: 203541
2014-03-11 04:37:49 +00:00