Commit Graph

17341 Commits

Author SHA1 Message Date
Eric Christopher
e6d97094b7 Remove unused argument to CreateTargetScheduleState and change
the TargetMachine to a TargetSubtargetInfo since everything
we wanted is off of that.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219382 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-09 01:59:35 +00:00
Eric Christopher
939dd38a09 Remove uses of getSubtargetImpl from ResourcePriorityQueue and
replace them with calls off of the MachineFuncton.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219381 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-09 01:59:31 +00:00
Eric Christopher
b78fd035a2 Remove the uses of getSubtargetImpl from InstrEmitter and remove
the now unused TargetMachine variable.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219379 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-09 01:35:29 +00:00
Eric Christopher
05597e9fa3 Use the subtarget on the dag to get TargetFrameLowering rather
than off the target machine.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219378 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-09 01:35:27 +00:00
Eric Christopher
31c9cd065a Remove uses of the TargetMachine from FunctionLoweringInfo
via caching TargetLowering and using the MachineFunction.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219375 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-09 00:57:31 +00:00
David Blaikie
7ed0e6d0c6 Push DwarfDebug::attachRangesOrLowHighPC down into DwarfCompileUnit
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219372 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-09 00:21:42 +00:00
David Blaikie
cbb705d900 Sink DwarfDebug::addScopeRangeList down into DwarfCompileUnit
(& add a few accessors/make a couple of things public for this - it's a
bit of a toss-up, but I think I prefer it this way, keeping some more of
the meaty code down in DwarfCompileUnit - if only to make for smaller
implementation files, etc)

I think we could simplify range handling a bit if we removed the range
lists from each unit and just put a single range list on DwarfDebug,
similar to address pooling.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219370 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-09 00:11:39 +00:00
Eric Christopher
6aaac28658 Remove unnecessary include.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219368 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-08 23:38:40 +00:00
Eric Christopher
f6d028047f Use both the cached TLI and the subtarget off of the DAG in
the DAG combiner.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219367 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-08 23:38:39 +00:00
Eric Christopher
5d61941de0 Remove getSubtargetImpl calls from FastISel, we can get it from
the MachineFunction where it's already cached.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219366 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-08 23:38:33 +00:00
David Blaikie
e988932602 Sink DwarfUnit::addSectionDelta into DwarfCompileUnit, the only place it's needed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219364 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-08 23:30:05 +00:00
David Blaikie
f616a4ba06 Reformat some stuff I missed in recent previous commits
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219356 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-08 23:09:42 +00:00
David Blaikie
46e29705c6 Sink and coalesce DwarfDebug.cpp::addSectionLabel and DwarfUnit::addSectionLabel down into DwarfCompileUnit::addSectionLabel
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219351 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-08 22:46:27 +00:00
Eric Christopher
50822e618c Remove dead call to getTypeToTransformTo. The result is
unused.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219347 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-08 22:25:45 +00:00
David Blaikie
3e9c8c557b DebugInfo: The rest of pushing DwarfDebug::constructScopeDIE down into DwarfCompileUnit
Funnily enough, I copied it, but didn't actually remove the original in
r219345. Let's do that.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219346 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-08 22:23:10 +00:00
David Blaikie
3f2f9695c5 Push DwarfDebug::constructScopeDIE down into DwarfCompileUnit
One of many steps to generalize subprogram emission to both the DWO and
non-DWO sections (to emit -gmlt-like data under fission). Once the
functions are pushed down into DwarfCompileUnit some of the data
structures will be pushed at least into DwarfFile so that they can be
unique per-file, allowing emission to both files independently.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219345 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-08 22:20:02 +00:00
Eric Christopher
b05e2be02c Remove a bunch of getSubtargetImpl calls since we already have
a cached TLI instance.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219342 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-08 21:08:32 +00:00
Timur Iskhodzhanov
0a5843e3b1 Fix COFF section index relocation should be 16 bits, not 32
Original patch by Andrey Guskov!
http://reviews.llvm.org/D5651



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219327 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-08 18:01:49 +00:00
Eric Christopher
5a2fda0ca1 Use the TargetLowering information we already have on the
SelectionDAG in SelectionDAGBuilder rather than going through
the TargetMachine for lookup.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219292 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-08 09:50:54 +00:00
Eric Christopher
c586355b06 Grab the TargetRegisterInfo off of the subtarget from the
MachineFunction rather than a lookup on the TargetMachine
to avoid unnecessary lookups.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219291 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-08 09:50:52 +00:00
Eric Christopher
5dd4454174 Replace calls to get the subtarget and TargetFrameLowering with
cached variables and a single call in the constructor.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219287 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-08 08:46:34 +00:00
Eric Christopher
c720405b2a Use cached subtarget rather than looking it up on the
TargetMachine again.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219285 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-08 07:51:41 +00:00
Eric Christopher
b7cd35b171 Cache TargetLowering on SelectionDAGISel and update previous
calls to getTargetLowering() with the cached variable.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219284 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-08 07:32:17 +00:00
Eric Christopher
f3358e3d49 Cache SelectionDAGISel TargetInstrInfo lookups on the class and
propagate. Also use the TargetSubtargetInfo and the MachineFunction
and move TargetRegisterInfo query closer to uses.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219273 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-08 01:58:03 +00:00
Eric Christopher
ede41a93d3 Reset the target options and optimization level as the first
thing we do inside selection dag. This code needs to be
migrated to queries on the function rather than global
data, but this organizes things before we start grabbing
the subtarget.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219271 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-08 01:58:01 +00:00
Eric Christopher
48b1918a1b Have the selection dag grab TargetLowering off of the subtarget
inside init rather than have it passed in as an argument.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219270 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-08 01:57:58 +00:00
Eric Christopher
6e36592a73 Have SelectionDAG's subtarget TargetSelectionDAGInfo be set
during init rather than construction time.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219262 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-08 00:32:59 +00:00
Sanjay Patel
ebc756d0d7 typos
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219221 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-07 17:38:33 +00:00
Sanjay Patel
87ce2e39df typos
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219220 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-07 17:36:50 +00:00
David Blaikie
08942b98d7 DebugInfo: Ensure that all debug location scope chains from instructions within a function, lead to the function itself.
Let me tell you a tale...

Originally committed in r211723 after discovering a nasty case of weird
scoping due to inlining, this was reverted in r211724 after it fired in
ASan/compiler-rt.

(minor diversion where I accidentally committed/reverted again in
r211871/r211873)

After further testing and fixing bugs in ArgumentPromotion (r211872) and
Inlining (r212065) it was recommitted in r212085. Reverted in r212089
after the sanitizer buildbots still showed problems.

Fixed another bug in ArgumentPromotion (r212128) found by this
assertion.

Recommitted in r212205, reverted in r212226 after it crashed some more
on sanitizer buildbots.

Fix clang some more in r212761.

Recommitted in r212776, reverted in r212793. ASan failures.
Recommitted in r213391, reverted in r213432, trying to reproduce flakey
ASan build failure.

Fixed bugs in r213805 (ArgPromo + DebugInfo), r213952
(LiveDebugVariables strips dbg_value intrinsics in functions not
described by debug info).

Recommitted in r214761, reverted in r214999, flakey failure on Windows
buildbot.

Fixed DeadArgElimination + DebugInfo bug in r219210.

Recommitting and hoping that's the last of it.

[That one burned down, fell over, then sank into the swamp.]

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219215 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-07 16:56:20 +00:00
Hal Finkel
807111a8f4 [DAGCombine] Remove SIGN_EXTEND-related inf-loop
The patch's author points out that, despite the function's documentation,
getSetCCResultType is only used to get the SETCC result type (with one
here-removed problematic exception). In one case, getSetCCResultType was being
used to get the predicate type to use for a SELECT node, and then
SIGN_EXTENDing (or truncating) to get the input predicate to match that type.
Unfortunately, this was happening inside visitSIGN_EXTEND, and creating new
SIGN_EXTEND nodes was causing an infinite loop. In addition, this behavior was
wrong if a target was not using ZeroOrNegativeOneBooleanContent. Lastly, the
extension/truncation seems unnecessary here: SELECT is defined as:

  Select(COND, TRUEVAL, FALSEVAL). If the type of the boolean COND is not i1
  then the high bits must conform to getBooleanContents.

So here we remove this use of getSetCCResultType and update
getSetCCResultType's documentation to reflect its actual uses.

Patch by deadal nix!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219141 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-06 20:19:47 +00:00
Sanjay Patel
b67100314b Fast-math fold: x / (y * sqrt(z)) -> x * (rsqrt(z) / y)
The motivation is to recognize code such as this from /llvm/projects/test-suite/SingleSource/Benchmarks/BenchmarkGame/n-body.c:

float distance = sqrt(dx * dx + dy * dy + dz * dz);
float mag = dt / (distance * distance * distance);

Without this patch, we don't match the sqrt as a reciprocal sqrt, so for PPC the new testcase in this patch produces:

   addis 3, 2, .LCPI4_2@toc@ha
   lfs 4, .LCPI4_2@toc@l(3)
   addis 3, 2, .LCPI4_1@toc@ha
   lfs 0, .LCPI4_1@toc@l(3)
   fcmpu 0, 1, 4
   beq 0, .LBB4_2
# BB#1:
   frsqrtes 4, 1
   addis 3, 2, .LCPI4_0@toc@ha
   lfs 5, .LCPI4_0@toc@l(3)
   fnmsubs 13, 1, 5, 1
   fmuls 6, 4, 4
   fmadds 1, 13, 6, 5
   fmuls 1, 4, 1
   fres 4, 1                <--- reciprocal of reciprocal square root
   fnmsubs 1, 1, 4, 0
   fmadds 4, 4, 1, 4
.LBB4_2:
   fmuls 1, 4, 2
   fres 2, 1
   fnmsubs 0, 1, 2, 0
   fmadds 0, 2, 0, 2
   fmuls 1, 3, 0
   blr

After the patch, this simplifies to:

frsqrtes 0, 1
addis 3, 2, .LCPI4_1@toc@ha
fres 5, 2
lfs 4, .LCPI4_1@toc@l(3)
addis 3, 2, .LCPI4_0@toc@ha
lfs 7, .LCPI4_0@toc@l(3)
fnmsubs 13, 1, 4, 1
fmuls 6, 0, 0
fnmsubs 2, 2, 5, 7
fmadds 1, 13, 6, 4
fmadds 2, 5, 2, 5
fmuls 0, 0, 1
fmuls 0, 0, 2
fmuls 1, 3, 0
blr

Differential Revision: http://reviews.llvm.org/D5628



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219139 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-06 19:31:18 +00:00
Benjamin Kramer
8ea5b7120f DbgValueHistoryCalculator: Store modified registers in a BitVector instead of std::set.
And iterate over the smaller map instead of the larger set first.  Reduces the time spent in
calculateDbgValueHistory by 30-40%.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219123 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-06 15:31:04 +00:00
David Blaikie
d53f7f4b22 DebugInfo: Sink constructImportedEntityDIE down into DwarfUnit from DwarfDebug.
It was just calling a bunch of DwarfUnit functions anyway, as can be
seen by the simplification of removing "TheCU" from all the function
calls in the implementation.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219103 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-06 05:37:24 +00:00
Chandler Carruth
560bddce20 [x86, dag] Teach the DAG combiner to prune inputs toa vector_shuffle
that are unused.

This allows the combiner to delete math feeding shuffles where the math
isn't actually necessary. This improves some of the vperm2x128 tests
that regressed when the vector shuffle lowering started actually
generating vperm instructions rather than forcibly decomposing them.

Sadly, this isn't enough to get this *really* right because we still
form a completely unnecessary permutation. To fix that, we also need to
fold shuffles which just rearrange concatenated or inserted subvectors.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219086 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-05 19:14:34 +00:00
David Blaikie
446817b4ef Remove unused map
This became unnecessary/unused in r208636

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219085 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-05 16:31:13 +00:00
Benjamin Kramer
814a2ffc7c Make AAMDNodes ctor and operator bool (!!!) explicit, mop up bugs and weirdness exposed by it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219068 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-04 22:44:29 +00:00
Benjamin Kramer
dbc6d9b9d7 Remove unnecessary copying or replace it with moves in a bunch of places.
NFC.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219061 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-04 16:55:56 +00:00
David Blaikie
53b95f3fb1 Sink DwarfDebug::updateSubprogramScopeDIE into DwarfCompileUnit
This requires exposing some of the current function state from
DwarfDebug. I hope there's not too much of that to expose as I go
through all the functions, but it still seems nicer to expose singular
data down to multiple consumers, than have consumers expose raw mapping
data structures up to DwarfDebug for building subprograms.

Part of a series of refactoring to allow subprograms in both the
skeleton and dwo CUs under Fission.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219060 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-04 16:24:00 +00:00
David Blaikie
dba26ca39c Reformatting accidentally left out of r219057
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219059 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-04 16:00:26 +00:00
David Blaikie
2c9ba7b7b1 Sink DwarfDebug::attachLowHighPC into DwarfCompileUnit
One of many things to sink down into DwarfCompileUnit to allow handling
of subprograms in both the skeleton and dwo CU under Fission.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219058 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-04 15:58:47 +00:00
David Blaikie
a2ec9db66b Move DwarfCompileUnit from DwarfUnit.h to its own header (DwarfCompileUnit.h)
In preparation for sinking all the subprogram emission code down from
DwarfDebug into DwarfCompileUnit, this will avoid bloating
DwarfUnit.h/cpp greatly and make concerns a bit more clear/isolated.

(sinking this handling down is part of the work to handle emitting
minimal subprograms for -gmlt-like data into the skeleton CU under
fission)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219057 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-04 15:49:50 +00:00
Duncan P. N. Exon Smith
83902832de Revert "Revert "DI: Fold constant arguments into a single MDString""
This reverts commit r218918, effectively reapplying r218914 after fixing
an Ocaml bindings test and an Asan crash.  The root cause of the latter
was a tightened-up check in `DILexicalBlock::Verify()`, so I'll file a
PR to investigate who requires the loose check (and why).

Original commit message follows.

--

This patch addresses the first stage of PR17891 by folding constant
arguments together into a single MDString.  Integers are stringified and
a `\0` character is used as a separator.

Part of PR17891.

Note: I've attached my testcases upgrade scripts to the PR.  If I've
just broken your out-of-tree testcases, they might help.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219010 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-03 20:01:09 +00:00
Adam Nemet
726942c8bb [ISel] Keep matching state consistent when folding during X86 address match
In the X86 backend, matching an address is initiated by the 'addr' complex
pattern and its friends.  During this process we may reassociate and-of-shift
into shift-of-and (FoldMaskedShiftToScaledMask) to allow folding of the
shift into the scale of the address.

However as demonstrated by the testcase, this can trigger CSE of not only the
shift and the AND which the code is prepared for but also the underlying load
node.  In the testcase this node is sitting in the RecordedNode and MatchScope
data structures of the matcher and becomes a deleted node upon CSE.  Returning
from the complex pattern function, we try to access it again hitting an assert
because the node is no longer a load even though this was checked before.

Now obviously changing the DAG this late is bending the rules but I think it
makes sense somewhat.  Outside of addresses we prefer and-of-shift because it
may lead to smaller immediates (FoldMaskAndShiftToScale is an even better
example because it create a non-canonical node).  We currently don't recognize
addresses during DAGCombiner where arguably this canonicalization should be
performed.  On the other hand, having this in the matcher allows us to cover
all the cases where an address can be used in an instruction.

I've also talked a little bit to Dan Gohman on llvm-dev who added the RAUW for
the new shift node in FoldMaskedShiftToScaledMask.  This RAUW is responsible
for initiating the recursive CSE on users
(http://lists.cs.uiuc.edu/pipermail/llvmdev/2014-September/076903.html) but it
is not strictly necessary since the shift is hooked into the visited user.  Of
course it's safer to keep the DAG consistent at all times (e.g. for accurate
number of uses, etc.).

So rather than changing the fundamentals, I've decided to continue along the
previous patches and detect the CSE.  This patch installs a very targeted
DAGUpdateListener for the duration of a complex-pattern match and updates the
matching state accordingly.  (Previous patches used HandleSDNode to detect the
CSE but that's not practical here).  The listener is only installed on X86.

I tested that there is no measurable overhead due to this while running
through the spec2k BC files with llc.  The only thing we pay for is the
creation of the listener.  The callback never ever triggers in spec2k since
this is a corner case.

Fixes rdar://problem/18206171

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219009 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-03 20:00:34 +00:00
Benjamin Kramer
63688e622c Eliminate some deep std::vector copies. NFC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218999 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-03 18:33:16 +00:00
Renato Golin
b157cb7afd Revert 202433 - Provide a target override for the latest regalloc heuristic
That commit was introduced in order to help investigate a problem in ARM
codegen breaking from commit 202304 (Add a limit to the heuristic that register
allocates instructions in local order). Recent analisys indicated that the
problem no longer exists, so I'm reverting this change.

See PR18996.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218981 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-03 12:20:53 +00:00
Chandler Carruth
bbb28e7e98 Fix the threshold added in r186434 (a re-apply of r185393) and updaated
to be a ManagedStatic in r218163 to not be a global variable written and
read to from within the innards of SpillPlacement.

This will fix a really scary race condition for anyone that has two
copies of LLVM running spill placement concurrently. Yikes!

This will also fix a really significant compile time hit that r218163
caused because the spill placement threshold read is actually in the
*very* hot path of this code. The memory fence on each read was showing
up as huge compile time regressions when spilling is responsible for
most of the compile time. For example, optimizing sanitized code showed
over 50% compile time regressions here. =/

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218921 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-02 22:23:14 +00:00
Duncan P. N. Exon Smith
32e192aeb3 Revert "DI: Fold constant arguments into a single MDString"
This reverts commit r218914 while I investigate some bots.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218918 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-02 22:15:31 +00:00
Duncan P. N. Exon Smith
0917b70630 DI: Fold constant arguments into a single MDString
This patch addresses the first stage of PR17891 by folding constant
arguments together into a single MDString.  Integers are stringified and
a `\0` character is used as a separator.

Part of PR17891.

Note: I've attached my testcases upgrade scripts to the PR.  If I've
just broken your out-of-tree testcases, they might help.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218914 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-02 21:56:57 +00:00
Adrian Prantl
02474a32eb Move the complex address expression out of DIVariable and into an extra
argument of the llvm.dbg.declare/llvm.dbg.value intrinsics.

Previously, DIVariable was a variable-length field that has an optional
reference to a Metadata array consisting of a variable number of
complex address expressions. In the case of OpPiece expressions this is
wasting a lot of storage in IR, because when an aggregate type is, e.g.,
SROA'd into all of its n individual members, the IR will contain n copies
of the DIVariable, all alike, only differing in the complex address
reference at the end.

By making the complex address into an extra argument of the
dbg.value/dbg.declare intrinsics, all of the pieces can reference the
same variable and the complex address expressions can be uniqued across
the CU, too.
Down the road, this will allow us to move other flags, such as
"indirection" out of the DIVariable, too.

The new intrinsics look like this:
declare void @llvm.dbg.declare(metadata %storage, metadata %var, metadata %expr)
declare void @llvm.dbg.value(metadata %storage, i64 %offset, metadata %var, metadata %expr)

This patch adds a new LLVM-local tag to DIExpressions, so we can detect
and pretty-print DIExpression metadata nodes.

What this patch doesn't do:

This patch does not touch the "Indirect" field in DIVariable; but moving
that into the expression would be a natural next step.

http://reviews.llvm.org/D4919
rdar://problem/17994491

Thanks to dblaikie and dexonsmith for reviewing this patch!

Note: I accidentally committed a bogus older version of this patch previously.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218787 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-01 18:55:02 +00:00