Commit Graph

15 Commits

Author SHA1 Message Date
Ahmed Bougacha 171f7b9986 [AArch64] Don't blindly lower f16/f128 FCCMPs.
Instead, extend f16 (like we do when lowering a standalone SETCC),
and let f128 be legalized to the RT calls.

Fixes PR26803.

llvm-svn: 263301
2016-03-11 22:02:58 +00:00
Balaram Makam 92431703d7 AArch64: Implement missed conditional compare sequences.
Summary:
This is an extension to the existing implementation of r242436 which
restricts to only select inputs. This version fixes missed opportunities
in pr26084 by attempting to lower conditional compare sequences of
and/or trees with setcc leafs. This will additionaly handle the case
when a tree with select input is not a conjunction-disjunction tree
but some of the sub trees are conjunction-disjunction trees.

Reviewers: jmolloy, t.p.northover, mcrosier, MatzeB

Subscribers: mcrosier, llvm-commits, junbuml, haicheng, mssimpso, gberry

Differential Revision: http://reviews.llvm.org/D16291

llvm-svn: 259387
2016-02-01 19:13:07 +00:00
Matthias Braun fdef49b183 AArch64ISel: Fix ccmp code selection matching deep expressions.
Some of the conditions necessary to produce ccmp sequences were only
checked in recursive calls to emitConjunctionDisjunctionTree() after
some of the earlier expressions were already built. Move all checks over
to isConjunctionDisjunctionTree() so they are all checked before we
start emitting instructions.

Also rename some variable to better reflect their usage.

llvm-svn: 258605
2016-01-23 04:05:22 +00:00
Ahmed Bougacha 8e491e2d02 [AArch64] Cleanup ccmp test check labels. NFC.
llvm-svn: 258541
2016-01-22 20:02:26 +00:00
Ahmed Bougacha 99209b90a4 [AArch64] Lower 2-CC FCCMPs (one/ueq) using AND'ed CCs.
The current behavior is incorrect, as the two CCs returned by
changeFPCCToAArch64CC, intended to be OR'ed, are instead used
in an AND ccmp chain.

Consider:
define i32 @t(float %a, float %b, float %c, float %d, i32 %e, i32 %f) {
  %cc1 = fcmp one float %a, %b
  %cc2 = fcmp olt float %c, %d
  %and = and i1 %cc1, %cc2
  %r = select i1 %and, i32 %e, i32 %f
  ret i32 %r
}

Assuming (%a < %b) and (%c < %d); we used to do:
  fcmp  s0, s1            # nzcv <- 1000
  orr   w8, wzr, #0x1     # w8 <- 1
  csel  w9, w8, wzr, mi   # w9 <- 1
  csel  w8, w8, w9, gt    # w8 <- 1
  fcmp  s2, s3            # nzcv <- 1000
  cset   w9, mi           # w9 <- 1
  tst    w8, w9           # (w8 & w9) == 1, so: nzcv <- 0000
  csel  w0, w0, w1, ne    # w0 <- w0

We now do:
  fcmp  s2, s3            # nzcv <- 1000
  fccmp s0, s1, #0, mi    #  mi, so: nzcv <- 1000
  fccmp s0, s1, #8, le    # !le, so: nzcv <- 1000
  csel  w0, w0, w1, pl    # !pl, so: w0 <- w1

In other words, we transformed:
  (c < d) &&  ((a < b) || (a > b))
into:
  (c < d) &&   (a u>= b) && (a u<= b)
whereas, per De Morgan's, we wanted:
  (c < d) && !((a u>= b) && (a u<= b))

Note that this problem doesn't occur in the test-suite.

changeFPCCToAArch64CC produces disjunct CCs; here, one -> mi/gt.
We can't represent that in the fccmp chain; it can't express
arbitrary OR sequences, as one comment explains:
  In general we can create code for arbitrary "... (and (and A B) C)"
  sequences.  We can also implement some "or" expressions, because
  "(or A B)" is equivalent to "not (and (not A) (not B))" and we can
  implement some  negation operations. [...] However there is no way
  to negate the result of a partial sequence.

Instead, introduce changeFPCCToANDAArch64CC, which produces the
conjunct cond codes:
- (a one b)
    == ((a olt b) || (a ogt b))
    == ((a ord b) && (a une b))
- (a ueq b)
    == ((a uno b) || (a oeq b))
    == ((a ule b) && (a uge b))

Note that, at first, one might think that, when PushNegate is true,
we should use the disjunct CCs, in effect doing:
  (a || b)
  = !(!a && !(b))
  = !(!a && !(b1 || b2))  <- changeFPCCToAArch64CC(b, b1, b2)
  = !(!a && !b1 && !b2)

However, we can take advantage of the fact that the CC is already
negated, which lets us avoid special-casing PushNegate and doing
the simpler to reason about:

  (a || b)
  = !(!a && (!b))
  = !(!a && (b1 && b2))   <- changeFPCCToANDAArch64CC(!b, b1, b2)
  = !(!a && b1 && b2)

This makes both emitConditionalCompare cases behave identically,
and produces correct ccmp sequences for the 2-CC fcmps.

llvm-svn: 258533
2016-01-22 19:43:54 +00:00
Matthias Braun 25fd09a756 AArch64: Fix testcase of r245640
llvm-svn: 245647
2015-08-21 00:23:19 +00:00
Matthias Braun 46e5639806 AArch64: Fix cmp;ccmp ordering
When producing conditional compare sequences for or operations we need
to negate the operands and the finally tested flags. The thing is if we negate
the finally tested flags this equals a logical negation of all previously
emitted expressions. There was a case missing where we have to order OR
expressions so they get emitted first.

This fixes http://llvm.org/PR24459

llvm-svn: 245641
2015-08-20 23:33:34 +00:00
Matthias Braun 266204b7dc AArch64: Do not create CCMP on multiple users.
Create CMP;CCMP sequences from and/or trees does not gain us anything if
the and/or tree is materialized to a GP register anyway. While most of
the code already checked for hasOneUse() there was one important case
missing.

llvm-svn: 245640
2015-08-20 23:33:31 +00:00
Matthias Braun 2bd6dd8d54 MachineScheduler: Restrict macroop fusion to data-dependent instructions.
Before creating a schedule edge to encourage MacroOpFusion check that:
- The predecessor actually writes a register that the branch reads.
- The predecessor has no successors in the ScheduleDAG so we can
  schedule it in front of the branch.

This avoids skewing the scheduling heuristic in cases where macroop
fusion cannot happen.

Differential Revision: http://reviews.llvm.org/D10745

llvm-svn: 242723
2015-07-20 22:34:44 +00:00
Matthias Braun af7d7709d6 AArch64: Implement conditional compare sequence matching.
This is a new iteration of the reverted r238793 /
http://reviews.llvm.org/D8232 which wrongly assumed that any and/or
trees can be represented by conditional compare sequences, however there
are some restrictions to that. This version fixes this and adds comments
that explain exactly what types of and/or trees can actually be
implemented as conditional compare sequences.

Related to http://llvm.org/PR20927, rdar://18326194

Differential Revision: http://reviews.llvm.org/D10579

llvm-svn: 242436
2015-07-16 20:02:37 +00:00
Matthias Braun 8321006d44 Revert "AArch64: Use CMP;CCMP sequences for and/or/setcc trees."
The patch triggers a miscompile on SPEC 2006 403.gcc with the (ref)
200.i and scilab.i inputs. I opened PR23866 to track analysis of this.

This reverts commit r238793.

llvm-svn: 239880
2015-06-17 04:02:32 +00:00
Matthias Braun 72b8f74813 AArch64: Use CMP;CCMP sequences for and/or/setcc trees.
Previously CCMP/FCCMP instructions were only used by the
AArch64ConditionalCompares pass for control flow. This patch uses them
for SELECT like instructions as well by matching patterns in ISelLowering.

PR20927, rdar://18326194

Differential Revision: http://reviews.llvm.org/D8232

llvm-svn: 238793
2015-06-01 22:31:17 +00:00
David Blaikie a79ac14fa6 [opaque pointer type] Add textual IR support for explicit type parameter to load instruction
Essentially the same as the GEP change in r230786.

A similar migration script can be used to update test cases, though a few more
test case improvements/changes were required this time around: (r229269-r229278)

import fileinput
import sys
import re

pat = re.compile(r"((?:=|:|^)\s*load (?:atomic )?(?:volatile )?(.*?))(| addrspace\(\d+\) *)\*($| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$)")

for line in sys.stdin:
  sys.stdout.write(re.sub(pat, r"\1, \2\3*\4", line))

Reviewers: rafael, dexonsmith, grosser

Differential Revision: http://reviews.llvm.org/D7649

llvm-svn: 230794
2015-02-27 21:17:42 +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 3b0846e8f7 AArch64/ARM64: move ARM64 into AArch64's place
This commit starts with a "git mv ARM64 AArch64" and continues out
from there, renaming the C++ classes, intrinsics, and other
target-local objects for consistency.

"ARM64" test directories are also moved, and tests that began their
life in ARM64 use an arm64 triple, those from AArch64 use an aarch64
triple. Both should be equivalent though.

This finishes the AArch64 merge, and everyone should feel free to
continue committing as normal now.

llvm-svn: 209577
2014-05-24 12:50:23 +00:00