Commit Graph

19 Commits

Author SHA1 Message Date
Sanjay Patel 1166f2ff9f fix memcpy/memset/memmove lowering when optimizing for size
Fixing MinSize attribute handling was discussed in D11363. 
This is a prerequisite patch to doing that.

The handling of OptSize when lowering mem* functions was broken
on Darwin because it wants to ignore -Os for these cases, but the
existing logic also made it ignore -Oz (MinSize).

The Linux change demonstrates a widespread problem. The backend
doesn't usually recognize the MinSize attribute by itself; it
assumes that if the MinSize attribute exists, then the OptSize 
attribute must also exist. 

Fixing this more generally will be a follow-on patch or two.

Differential Revision: http://reviews.llvm.org/D11568

llvm-svn: 243693
2015-07-30 21:41:50 +00:00
Sanjay Patel 94a7433cde add tests to show broken current behavior of minsize attribute
llvm-svn: 243451
2015-07-28 17:18:25 +00:00
David Blaikie f72d05bc7b [opaque pointer type] Add textual IR support for explicit type parameter to gep operator
Similar to gep (r230786) and load (r230794) changes.

Similar migration script can be used to update test cases, which
successfully migrated all of LLVM and Polly, but about 4 test cases
needed manually changes in Clang.

(this script will read the contents of stdin and massage it into stdout
- wrap it in the 'apply.sh' script shown in previous commits + xargs to
apply it over a large set of test cases)

import fileinput
import sys
import re

rep = re.compile(r"(getelementptr(?:\s+inbounds)?\s*\()((<\d*\s+x\s+)?([^@]*?)(|\s*addrspace\(\d+\))\s*\*(?(3)>)\s*)(?=$|%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|zeroinitializer|<|\[\[[a-zA-Z]|\{\{)", re.MULTILINE | re.DOTALL)

def conv(match):
  line = match.group(1)
  line += match.group(4)
  line += ", "
  line += match.group(2)
  return line

line = sys.stdin.read()
off = 0
for match in re.finditer(rep, line):
  sys.stdout.write(line[off:match.start()])
  sys.stdout.write(conv(match))
  off = match.end()
sys.stdout.write(line[off:])

llvm-svn: 232184
2015-03-13 18:20:45 +00:00
Stephen Lin f799e3f944 Convert CodeGen/*/*.ll tests to use the new CHECK-LABEL for easier debugging. No functionality change and all tests pass after conversion.
This was done with the following sed invocation to catch label lines demarking function boundaries:
    sed -i '' "s/^;\( *\)\([A-Z0-9_]*\):\( *\)test\([A-Za-z0-9_-]*\):\( *\)$/;\1\2-LABEL:\3test\4:\5/g" test/CodeGen/*/*.ll
which was written conservatively to avoid false positives rather than false negatives. I scanned through all the changes and everything looks correct.

llvm-svn: 186258
2013-07-13 20:38:47 +00:00
Chandler Carruth 05920b1847 Fix the root cause of PR15348 by correctly handling alignment 0 on
memory intrinsics in the SDAG builder.

When alignment is zero, the lang ref says that *no* alignment
assumptions can be made. This is the exact opposite of the internal API
contracts of the DAG where alignment 0 indicates that the alignment can
be made to be anything desired.

There is another, more explicit alignment that is better suited for the
role of "no alignment at all": an alignment of 1. Map the intrinsic
alignment to this early so that we don't end up generating aligned DAGs.

It is really terrifying that we've never seen this before, but we
suddenly started generating a large number of alignment 0 memcpys due to
the new code to do memcpy-based copying of POD class members. That patch
contains a bug that rounds bitfield alignments down when they are the
first field. This can in turn produce zero alignments.

This fixes weird crashes I've seen in library users of LLVM on 32-bit
hosts, etc.

llvm-svn: 176022
2013-02-25 14:20:21 +00:00
Evan Cheng c8444b159a PR14896: Handle memcpy from constant string where the memcpy size is larger than the string size.
llvm-svn: 172124
2013-01-10 22:13:27 +00:00
Benjamin Kramer 2f47a3fb07 Fix broken check lines.
I really need to find a way to automate this, but I can't come up with a regex
that has no false positives while handling tricky cases like custom check
prefixes.

llvm-svn: 162097
2012-08-17 12:28:26 +00:00
Chris Lattner 6987fdb620 Add a test for the miscompilation my recent ConstantDataArray patches introduced, to make sure
we don't regress on it in the future.

llvm-svn: 149803
2012-02-05 02:37:36 +00:00
Evan Cheng 13bcc6c1c7 Add Mode64Bit feature and sink it down to MC layer.
llvm-svn: 134641
2011-07-07 21:06:52 +00:00
Evan Cheng a048c83fe4 Revert r122955. It seems using movups to lower memcpy can cause massive regression (even on Nehalem) in edge cases. I also didn't see any real performance benefit.
llvm-svn: 123015
2011-01-07 19:35:30 +00:00
Evan Cheng 7998b1d6fe Use movups to lower memcpy and memset even if it's not fast (like corei7).
The theory is it's still faster than a pair of movq / a quad of movl. This
will probably hurt older chips like P4 but should run faster on current
and future Intel processors. rdar://8817010

llvm-svn: 122955
2011-01-06 07:58:36 +00:00
Evan Cheng 3ae2b79aa3 Re-implement r122936 with proper target hooks. Now getMaxStoresPerMemcpy
etc. takes an option OptSize. If OptSize is true, it would return
the inline limit for functions with attribute OptSize.

llvm-svn: 122952
2011-01-06 06:52:41 +00:00
Evan Cheng c052ba7ff3 Revert r122936. I'll re-implement the change.
llvm-svn: 122949
2011-01-06 06:17:53 +00:00
Evan Cheng 06536e7158 r105228 reduced the memcpy / memset inline limit to 4 with -Os to avoid blowing
up freebsd bootloader. However, this doesn't make much sense for Darwin, whose
-Os is meant to optimize for size only if it doesn't hurt performance.
rdar://8821501

llvm-svn: 122936
2011-01-06 01:04:47 +00:00
Chris Lattner 14c46517b5 fix PR6623: when optimizing for size, don't inline memcpy/memsets
that are too large.  This causes the freebsd bootloader to be too
large apparently.

It's unclear if this should be an -Os or -Oz thing.  Thoughts welcome.

llvm-svn: 105228
2010-05-31 17:30:14 +00:00
Chris Lattner 291a189cda upgrade and filecheckize this test.
llvm-svn: 105227
2010-05-31 17:27:17 +00:00
Evan Cheng b7a20ee5b5 Add nounwind.
llvm-svn: 100482
2010-04-05 22:30:05 +00:00
Dan Gohman 40503396da Eliminate more uses of llvm-as and llvm-dis.
llvm-svn: 81290
2009-09-08 23:54:48 +00:00
Rafael Espindola 6c04ac1db0 Refactor the memcpy lowering for the x86 target.
The only generated code difference is that now we call memcpy when
the size of the array is unknown. This matches GCC behavior and is
better since the run time value can be arbitrarily large.

llvm-svn: 42433
2007-09-28 12:53:01 +00:00