Commit Graph

18 Commits

Author SHA1 Message Date
Kyle Butt 267164df0a Codegen: Fix broken assumption in Tail Merge.
Tail merge was making the assumption that a layout successor or
predecessor was always a cfg successor/predecessor. Remove that
assumption. Changes to tests are necessary because the errant cfg edges
were preventing optimizations.

llvm-svn: 273700
2016-06-24 18:16:36 +00:00
David Blaikie 79e6c74981 [opaque pointer type] Add textual IR support for explicit type parameter to getelementptr instruction
One of several parallel first steps to remove the target type of pointers,
replacing them with a single opaque pointer type.

This adds an explicit type parameter to the gep instruction so that when the
first parameter becomes an opaque pointer type, the type to gep through is
still available to the instructions.

* This doesn't modify gep operators, only instructions (operators will be
  handled separately)

* Textual IR changes only. Bitcode (including upgrade) and changing the
  in-memory representation will be in separate changes.

* geps of vectors are transformed as:
    getelementptr <4 x float*> %x, ...
  ->getelementptr float, <4 x float*> %x, ...
  Then, once the opaque pointer type is introduced, this will ultimately look
  like:
    getelementptr float, <4 x ptr> %x
  with the unambiguous interpretation that it is a vector of pointers to float.

* address spaces remain on the pointer, not the type:
    getelementptr float addrspace(1)* %x
  ->getelementptr float, float addrspace(1)* %x
  Then, eventually:
    getelementptr float, ptr addrspace(1) %x

Importantly, the massive amount of test case churn has been automated by
same crappy python code. I had to manually update a few test cases that
wouldn't fit the script's model (r228970,r229196,r229197,r229198). The
python script just massages stdin and writes the result to stdout, I
then wrapped that in a shell script to handle replacing files, then
using the usual find+xargs to migrate all the files.

update.py:
import fileinput
import sys
import re

ibrep = re.compile(r"(^.*?[^%\w]getelementptr inbounds )(((?:<\d* x )?)(.*?)(| addrspace\(\d\)) *\*(|>)(?:$| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$))")
normrep = re.compile(       r"(^.*?[^%\w]getelementptr )(((?:<\d* x )?)(.*?)(| addrspace\(\d\)) *\*(|>)(?:$| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$))")

def conv(match, line):
  if not match:
    return line
  line = match.groups()[0]
  if len(match.groups()[5]) == 0:
    line += match.groups()[2]
  line += match.groups()[3]
  line += ", "
  line += match.groups()[1]
  line += "\n"
  return line

for line in sys.stdin:
  if line.find("getelementptr ") == line.find("getelementptr inbounds"):
    if line.find("getelementptr inbounds") != line.find("getelementptr inbounds ("):
      line = conv(re.match(ibrep, line), line)
  elif line.find("getelementptr ") != line.find("getelementptr ("):
    line = conv(re.match(normrep, line), line)
  sys.stdout.write(line)

apply.sh:
for name in "$@"
do
  python3 `dirname "$0"`/update.py < "$name" > "$name.tmp" && mv "$name.tmp" "$name"
  rm -f "$name.tmp"
done

The actual commands:
From llvm/src:
find test/ -name *.ll | xargs ./apply.sh
From llvm/src/tools/clang:
find test/ -name *.mm -o -name *.m -o -name *.cpp -o -name *.c | xargs -I '{}' ../../apply.sh "{}"
From llvm/src/tools/polly:
find test/ -name *.ll | xargs ./apply.sh

After that, check-all (with llvm, clang, clang-tools-extra, lld,
compiler-rt, and polly all checked out).

The extra 'rm' in the apply.sh script is due to a few files in clang's test
suite using interesting unicode stuff that my python script was throwing
exceptions on. None of those files needed to be migrated, so it seemed
sufficient to ignore those cases.

Reviewers: rafael, dexonsmith, grosser

Differential Revision: http://reviews.llvm.org/D7636

llvm-svn: 230786
2015-02-27 19:29:02 +00:00
Tim Northover b4ddc0845a ARM & AArch64: make use of common cmpxchg idioms after expansion
The C and C++ semantics for compare_exchange require it to return a bool
indicating success. This gets mapped to LLVM IR which follows each cmpxchg with
an icmp of the value loaded against the desired value.

When lowered to ldxr/stxr loops, this extra comparison is redundant: its
results are implicit in the control-flow of the function.

This commit makes two changes: it replaces that icmp with appropriate PHI
nodes, and then makes sure earlyCSE is called after expansion to actually make
use of the opportunities revealed.

I've also added -{arm,aarch64}-enable-atomic-tidy options, so that
existing fragile tests aren't perturbed too much by the change. Many
of them either rely on undef/unreachable too pervasively to be
restored to something well-defined (particularly while making sure
they test the same obscure assert from many years ago), or depend on a
particular CFG shape, which is disrupted by SimplifyCFG.

rdar://problem/16227836

llvm-svn: 209883
2014-05-30 10:09:59 +00:00
Evan Cheng 0be4144a68 Allow machine-cse to look across MBB boundary when cse'ing instructions that
define physical registers. It's currently very restrictive, only catching
cases where the CE is in an immediate (and only) predecessor. But it catches
a surprising large number of cases.

rdar://10660865

llvm-svn: 147827
2012-01-10 02:02:58 +00:00
Owen Anderson 0b9b9da6c8 Teach SelectionDAG to match more calls to libm functions onto existing SDNodes. Mark these nodes as illegal by default, unless the target declares otherwise.
llvm-svn: 146171
2011-12-08 19:32:14 +00:00
Stuart Hastings aa02c0847d Since I can't reproduce the failures from 131261, re-trying with a
simplified version.  <rdar://problem/9298790>

llvm-svn: 131274
2011-05-13 00:51:54 +00:00
Stuart Hastings 8d57d8ea64 Revert 131266 and 131261 due to buildbot complaints.
rdar://problem/9298790

llvm-svn: 131269
2011-05-13 00:15:17 +00:00
Stuart Hastings ef4940254f Tweak 131261 (thumb2-cbnz.ll) to generate the intended cbnz.
rdar://problem/9298790

llvm-svn: 131266
2011-05-13 00:10:03 +00:00
Stuart Hastings 89f1b47e3a Non-fast-isel followup to 129634; correctly handle branches controlled
by non-CMP expressions.  The executable test case (129821) would test
this as well, if we had an "-O0 -disable-arm-fast-isel" LLVM-GCC
tester.  Alas, the ARM assembly would be very difficult to check with
FileCheck.

The thumb2-cbnz.ll test is affected; it generates larger code (tst.w
vs. cmp #0), but I believe the new version is correct.
rdar://problem/9298790

llvm-svn: 131261
2011-05-12 23:36:41 +00:00
Eli Friedman 5401962643 Re-revert r130877; it's apparently causing a regression on 197.parser,
possibly related to cbnz formation.

llvm-svn: 130977
2011-05-06 05:23:07 +00:00
Eli Friedman 0fe4608af2 Re-commit r130862 with a minor change to avoid an iterator running off the edge in some cases.
Original message:

Teach MachineCSE how to do simple cross-block CSE involving physregs.  This allows, for example, eliminating duplicate cmpl's on x86. Part of rdar://problem/8259436 .

llvm-svn: 130877
2011-05-04 22:10:36 +00:00
Eli Friedman 3bd79ba856 Back out r130862; it appears to be breaking bootstrap.
llvm-svn: 130867
2011-05-04 20:48:42 +00:00
Eli Friedman a16fc2fec0 Teach MachineCSE how to do simple cross-block CSE involving physregs. This allows, for example, eliminating duplicate cmpl's on x86. Part of rdar://problem/8259436 .
llvm-svn: 130862
2011-05-04 19:54:24 +00:00
Evan Cheng 2d51c7c592 Allow ARM if-converter to be run after post allocation scheduling.
- This fixed a number of bugs in if-converter, tail merging, and post-allocation
  scheduler. If-converter now runs branch folding / tail merging first to
  maximize if-conversion opportunities.
- Also changed the t2IT instruction slightly. It now defines the ITSTATE
  register which is read by instructions in the IT block.
- Added Thumb2 specific hazard recognizer to ensure the scheduler doesn't
  change the instruction ordering in the IT block (since IT mask has been
  finalized). It also ensures no other instructions can be scheduled between
  instructions in the IT block.

This is not yet enabled.

llvm-svn: 106344
2010-06-18 23:09:54 +00:00
Rafael Espindola 29dda21e96 Remove arm_apcscc from the test files. It is the default and doing this
matches what llvm-gcc and clang now produce.

llvm-svn: 106221
2010-06-17 15:18:27 +00:00
Dan Gohman 64b5d0f468 Add support for tail duplication to BranchFolding, and extend
tail merging support to handle more cases.
 - Recognize several cases where tail merging is beneficial even when
   the tail size is smaller than the generic threshold.
 - Make use of MachineInstrDesc::isBarrier to help detect
   non-fallthrough blocks.
 - Check for and avoid disrupting fall-through edges in more cases.

llvm-svn: 86871
2009-11-11 19:48:59 +00:00
Evan Cheng 50bc004b67 Fix tests.
llvm-svn: 85723
2009-11-01 18:13:29 +00:00
Evan Cheng 6f29ad9170 Use cbz and cbnz instructions.
llvm-svn: 85698
2009-10-31 23:46:45 +00:00