17085 Commits

Author SHA1 Message Date
Hans Wennborg
efa23d332a PeepholeOptimizer: make parameter ref to SmallPtrSetImpl
This makes the function type independent of the in-line size
of LocalMIs.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215356 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-11 13:52:46 +00:00
Hans Wennborg
4d97a1a559 Make this SmallVector size a power of two as suggested by Chandler
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215355 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-11 13:47:57 +00:00
Jiangning Liu
0679d2d0a4 In Machine CSE pass, the source register of a COPY machine instruction can
be propagated to all its users, and this propagation could increase the 
probability of finding common subexpressions. If the COPY has only one user,
the COPY itself can be removed.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215344 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-11 05:17:19 +00:00
Hans Wennborg
07f1b21cb5 Re-commit "Increase the size of this SmallVector in PeepholeOptimizer." (r215340)
This time, also update the function that receives a reference to the SmallPtrSet as
a parameter.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215342 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-11 02:50:43 +00:00
Hans Wennborg
cb57e03fa3 Revert "Increase the size of this SmallVector in PeepholeOptimizer." (r215340)
That broke the build:

/data/buildslave/clang-amd64-freebsd/src-llvm/lib/CodeGen/PeepholeOptimizer.cpp:729:46: error: non-const lvalue reference to type 'SmallPtrSet<[...], 8>' cannot bind to a value of unrelated type 'SmallPtrSet<[...], 16>'
        Changed |= optimizeExtInstr(MI, MBB, LocalMIs);
                                             ^~~~~~~~
/data/buildslave/clang-amd64-freebsd/src-llvm/lib/CodeGen/PeepholeOptimizer.cpp:265:49: note: passing argument to parameter 'LocalMIs' here
                 SmallPtrSet<MachineInstr*, 8> &LocalMIs) {
                                                ^




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215341 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-11 02:34:52 +00:00
Hans Wennborg
9796e980eb Increase the size of this SmallVector in PeepholeOptimizer.
During a Clang build, the median size of this was 9

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215340 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-11 02:21:34 +00:00
Hans Wennborg
e4506cddc5 Increase the size of SpillPlacement::BlockFrequencies.
This SmallVector's median size during a Clang build was 7.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215338 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-11 02:21:30 +00:00
Hans Wennborg
d9dd9692af Increase the size of this SmallVector in CloneNodeWithValues.
In a Clang bootstrap, the size of this vector was always 6.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215335 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-11 02:21:19 +00:00
Hans Wennborg
6adf338dc3 Increase the size of DwarfAccelTable::TableHeaderData::Atoms.
During a Clang bootstrap, it seems this SmallVector always contains 3 elements.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215334 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-11 02:18:15 +00:00
Petar Jovanovic
97b0c63f6b Add support for scalarizing cttz_zero_undef
Follow up to r214266. Add missing case in ScalarizeVectorResult() for
cttz_zero_undef.

Differential Revision: http://reviews.llvm.org/D4813


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215330 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-10 22:49:54 +00:00
Saleem Abdulrasool
8eab0e68d3 CodeGen: switch to a range based for loop
Use a range based for loop instead of manual iteration.  NFC.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215287 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-09 17:21:29 +00:00
David Blaikie
6d56b950a9 DebugInfo: Recommit (reverted in r215217, originally committed in r215157) the assertion that no argument variable is overwritten by subsequent argument variables.
This turned up a bug in clang where arguments were emitted with
duplicate argument numbers (see r215227).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215228 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-08 17:12:35 +00:00
Pedro Artigas
ef6ddcf87a Added a TLI hook to signal that the target does not have or does not care about
floating point exceptions, added use of flag to fold potentially exception 
raising floating point math in selection DAG. No functionality change, as 
targets have to explicitly ask for this behavior and none does today.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215222 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-08 16:46:53 +00:00
David Blaikie
8bbca2cf38 DebugInfo: Remove assertion (added in r215157) that's firing on a blocks
test in the test-suite while I investigate further.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215217 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-08 16:21:50 +00:00
Josh Klontz
b79931d94e Add missing Interpreter intrinsic lowering for sin, cos and ceil
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215209 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-08 15:00:12 +00:00
Patrik Hagglund
cf403861a3 [pr19635] Revert most of r170537, and add new testcase.
Patch provided by Andrey Kuharev.

Sorry, r170537 was obviously wrong.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215190 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-08 08:21:19 +00:00
Akira Hatanaka
43f6ce9289 [stack protector] Look through bitcasts to get global variable
__stack_chk_guard.

Handle the case where the pointer operand of the load instruction that loads the
stack guard is not a global variable but instead a bitcast.

%StackGuard = load i8** bitcast (i64** @__stack_chk_guard to i8**)
call void @llvm.stackprotector(i8* %StackGuard, i8** %StackGuardSlot)

Original test case provided by Ana Pazos.

This fixes PR20558.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215167 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-07 23:08:24 +00:00
David Blaikie
263998aa1d DebugInfo: Fix overwriting/loss of inlined arguments to recursively inlined functions.
Due to an unnecessary special case, inlined arguments that happened to
be from the same function as they were inlined into were misclassified
as non-inline arguments and would overwrite the non-inlined arguments.

Assert that we never overwrite a function's arguments, and stop
misclassifying inlined arguments as non-inline arguments to fix this
issue.

Excuse the rather crappy test case - handcrafted IR might do better, or
someone who understands better how to tickle the inliner to create a
recursive inlining situation like this (though it may also be necessary
to tickle the variable in a particular way to cause it to be recorded in
the MMI side table and go down this particular path for location
information).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215157 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-07 22:22:49 +00:00
Eric Christopher
aa5b9c0f6f Temporarily Revert "Nuke the old JIT." as it's not quite ready to
be deleted. This will be reapplied as soon as possible and before
the 3.6 branch date at any rate.

Approved by Jim Grosbach, Lang Hames, Rafael Espindola.

This reverts commits r215111, 215115, 215116, 215117, 215136.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215154 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-07 22:02:54 +00:00
Gerolf Hoflehner
9fbb012404 Debugging Utility - optional ability for dumping critical path length
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215153 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-07 21:49:44 +00:00
Gerolf Hoflehner
e4fa341dde MachineCombiner Pass for selecting faster instruction sequence on AArch64
Re-commit of r214832,r21469 with a work-around that
avoids the previous problem with gcc build compilers

The work-around is to use SmallVector instead of ArrayRef
of basic blocks in preservesResourceLen()/MachineCombiner.cpp



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215151 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-07 21:40:58 +00:00
Frederic Riss
7d05a0fbc8 test commit: remove trailing whitespace.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215138 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-07 20:04:00 +00:00
Akira Hatanaka
70b56056a1 [Branch probability] Recompute branch weights of tail-merged basic blocks.
BranchFolderPass was not correctly setting the basic block branch weights when
tail-merging created or merged blocks. This patch recomutes the weights of
tail-merged blocks using the following formula:

branch_weight(merged block to successor j) =
sum(block_frequency(bb) * branch_probability(bb -> j))

bb is a block that is in the set of merged blocks.

<rdar://problem/16256423>


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215135 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-07 19:30:13 +00:00
Rafael Espindola
875710a2fd Nuke the old JIT.
I am sure we will be finding bits and pieces of dead code for years to
come, but this is a good start.

Thanks to Lang Hames for making MCJIT a good replacement!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215111 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-07 14:21:18 +00:00
David Blaikie
a0a7ad427a Revert "Reapply "DebugInfo: Ensure that all debug location scope chains from instructions within a function, lead to the function itself.""
This reverts commit r214761.

Revert while Reid investigates & provides a reproduction for an
assertion failure for this on Windows.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214999 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-06 22:30:12 +00:00
Eric Christopher
41612a9b85 Remove the target machine from CCState. Previously it was only used
to get the subtarget and that's accessible from the MachineFunction
now. This helps clear the way for smaller changes where we getting
a subtarget will require passing in a MachineFunction/Function as
well.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214988 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-06 18:45:26 +00:00
Adrian Prantl
6cdc374786 Improve performance of calculateDbgValueHistory.
In r210492 the logic of calculateDbgValueHistory was changed to end
register variable live ranges at the end of MBB conditionally on
the fact that the register was or not clobbered by the function body.

This requires an initial scan of all the operands of the function
to collect all clobbered registers. In a second pass over all
instructions, we compare this set with the set of clobbered
registers for the current MachineInstruction. This modification
incurred a compilation time regression on some benchmarks: the
debug info emission phase takes ~10% more time.

While a small performance hit is unavoidable due to the initial
scan requirement, we can improve the situation by avoiding to
create too many temporary sets and just use lambdas to work directly
on the result of the initial scan.

Fixes <rdar://problem/17884104>

Patch by Frederic Riss!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214987 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-06 18:41:24 +00:00
Adrian Prantl
6e62bbdafc Cleanup collectChangingRegs
The handling of the epilogue is best expressed as an early exit and
there is no reason to look for register defs in DbgValue MIs.

Patch by Frederic Riss!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214986 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-06 18:41:19 +00:00
Reid Kleckner
9688239469 Round up the size of byval arguments to MinAlign
Otherwise we can end up with an argument frame size that is not a
multiple of stack slot size, which is very awkward.

This fixes PR20547, which was a bug in x86_64 Sys V vararg handling.
However, it's much easier to test this with x86 callee-cleanup
functions, which previously ended in "retl $6" instead of "retl $8".

This does affect behavior of all backends, but it presumably fixes the
same bug in all of them.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214980 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-06 17:57:23 +00:00
Sanjay Patel
72a8b11fea use register iterators that include self to reduce code duplication in CriticalAntiDepBreaker
This patch addresses 2 FIXME comments that I added to CriticalAntiDepBreaker while fixing PR20020.

Initialize an MCSubRegIterator and an MCRegAliasIterator to include the self reg.

Assuming that works as advertised, there should be functional difference with this patch, just less code.

Also, remove the associated asserts - we're setting those values just before, so the asserts don't do anything meaningful.

Differential Revision: http://reviews.llvm.org/D4566



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214973 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-06 15:58:15 +00:00
David Blaikie
8480beefd0 DebugInfo: Assert that any CU for which debug_loc lists are emitted, has at least one range.
This was coming in weird debug info that had variables (and hence
debug_locs) but was in GMLT mode (because it was missing the 13th field
of the compile_unit metadata) so no ranges were constructed. We should
always have at least one range for any CU with a debug_loc in it -
because the range should cover the debug_loc.

The assertion just ensures that the "!= 1" range case inside the
subsequent loop doesn't get entered for the case where there are no
ranges at all, which should never reach here in the first place.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214939 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-06 00:21:25 +00:00
David Blaikie
5bfa4ba44d DebugInfo: Move the reference to the CU from the location list entry to the list itself, since it is constant across an entire list.
This simplifies construction and usage while making the data structure
smaller. It was a holdover from the days when we didn't have a separate
DebugLocList and all we had was a flat list of DebugLocEntries.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214933 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-05 23:14:16 +00:00
Sanjay Patel
6902c687b0 Optimize vector fabs of bitcasted constant integer values.
Allow vector fabs operations on bitcasted constant integer values to be optimized
in the same way that we already optimize scalar fabs.

So for code like this:
%bitcast = bitcast i64 18446744069414584320 to <2 x float> ; 0xFFFF_FFFF_0000_0000
%fabs = call <2 x float> @llvm.fabs.v2f32(<2 x float> %bitcast)
%ret = bitcast <2 x float> %fabs to i64

Instead of generating something like this:

movabsq (constant pool loadi of mask for sign bits)
vmovq   (move from integer register to vector/fp register)
vandps  (mask off sign bits)
vmovq   (move vector/fp register back to integer return register)

We should generate:

mov     (put constant value in return register)

I have also removed a redundant clause in the first 'if' statement:
N0.getOperand(0).getValueType().isInteger()

is the same thing as:
IntVT.isInteger()

Testcases for x86 and ARM added to existing files that deal with vector fabs.
One existing testcase for x86 removed because it is no longer ideal.

For more background, please see:
http://reviews.llvm.org/D4770

And:
http://llvm.org/bugs/show_bug.cgi?id=20354

Differential Revision: http://reviews.llvm.org/D4785


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214892 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-05 17:35:22 +00:00
David Blaikie
1d15bbc006 Partially revert r214761 that asserted that all concrete debug info variables had DIEs, due to a failure on Darwin.
I'll work on a reduction and fix after this.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214880 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-05 16:47:23 +00:00
Eric Christopher
6035518e3b Have MachineFunction cache a pointer to the subtarget to make lookups
shorter/easier and have the DAG use that to do the same lookup. This
can be used in the future for TargetMachine based caching lookups from
the MachineFunction easily.

Update the MIPS subtarget switching machinery to update this pointer
at the same time it runs.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214838 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-05 02:39:49 +00:00
Pedro Artigas
3da024594f Changed the liveness tracking in the RegisterScavenger
to use register units instead of registers.

reviewed by Jakob Stoklund Olesen.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214798 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-04 23:07:49 +00:00
Chandler Carruth
8a74e2fc07 [SDAG] Fix a really, really terrible bug in the DAG combiner.
This code is completely wrong. It is also dead, as if it were to *ever*
run, it would crash. Fortunately, after my work to the combiner, it is
at least *possible* to reach the code, and llvm-stress has found a test
case. Thanks to Patrick for reporting.

It would be really good if anyone who remembers how this code works and
what it was intended to do could add some more obvious test coverage
instead of my completely contrived and reduced test case. My test case
was so brittle I left a bread crumb comment in it to help the next
person to stumble on it and not know what it was actually testing for.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214785 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-04 21:29:59 +00:00
Eric Christopher
9f85dccfc6 Remove the TargetMachine forwards for TargetSubtargetInfo based
information and update all callers. No functional change.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214781 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-04 21:25:23 +00:00
David Blaikie
df5eef292d Reapply "DebugInfo: Ensure that all debug location scope chains from instructions within a function, lead to the function itself."
Originally reverted in r213432 with flakey failures on an ASan self-host
build. After reduction it seems to be the same issue fixed in r213805
(ArgPromo + DebugInfo: Handle updating debug info over multiple
applications of argument promotion) and r213952 (by having
LiveDebugVariables strip dbg_value intrinsics in functions that are not
described by debug info). Though I cannot explain why this failure was
flakey...

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214761 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-04 19:30:08 +00:00
Chandler Carruth
53dd6f7830 [x86] Don't add nodes to the combined set (and prune subsequent
combines) until they are legal.

Doing it the old way could, when the stars align *just* right, cause
a node to get into the combine set prior to being legalized. Then, when
the same node showed up as an operand to another node later on (but not
so much later on that it had been deleted as dead) we would fail to add
it back to the worklist thinking it had already been combined. This
would in turn cause it to not be legalized. Fortunately, we can also
walk the operands looking for uncombined (and thus potentially
un-legalized) nodes late. It will still ensure that we walk all operands
of all nodes and send all of them through both the legalizer without
changes and the combiner at least once. (Which was the original goal of
this).

I have a test case for this bug, but it is terribly brittle. For
example, it will stop finding the bug the moment I enable the new
shuffle lowering. I don't yet have any test case that reliably exercises
this bug, and it isn't clear that it will be possible to craft one. It
is entirely possible that with the new shuffle lowering the two forms of
doing this are precisely equivalent. That doesn't mean we shouldn't take
the more conservative approach of insisting on things in the combined
set having survived the legalizer.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214673 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-03 23:10:59 +00:00
Saleem Abdulrasool
335c0ca2c6 CodeGen: silence a warning
GCC 4.8.2 objects to the tautological condition in the assert as the unsigned
value is guaranteed to be >= 0.  Simplify the assertion by dropping the
tautological condition.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214671 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-03 23:00:38 +00:00
Sanjay Patel
0f2bc49126 fix for PR20354 - Miscompile of fabs due to vectorization
This is intended to be the minimal change needed to fix PR20354 ( http://llvm.org/bugs/show_bug.cgi?id=20354 ). The check for a vector operation was wrong; we need to check that the fabs itself is not a vector operation.

This patch will not generate the optimal code. A constant pool load and 'and' op will be generated instead of just returning a value that we can calculate in advance (as we do for the scalar case). I've put a 'TODO' comment for that here and expect to have that patch ready soon.

There is a very similar optimization that we can do in visitFNEG, so I've put another 'TODO' there and expect to have another patch for that too.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214670 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-03 22:48:23 +00:00
Gerolf Hoflehner
b0b708854e MachineCombiner Pass for selecting faster instruction
sequence -  target independent framework

 When the DAGcombiner selects instruction sequences
 it could increase the critical path or resource len.

 For example, on arm64 there are multiply-accumulate instructions (madd,
 msub). If e.g. the equivalent  multiply-add sequence is not on the
 crictial path it makes sense to select it instead of  the combined,
 single accumulate instruction (madd/msub). The reason is that the
 conversion from add+mul to the madd could lengthen the critical path
 by the latency of the multiply.

 But the DAGCombiner would always combine and select the madd/msub
 instruction.

 This patch uses machine trace metrics to estimate critical path length
 and resource length of an original instruction sequence vs a combined
 instruction sequence and picks the faster code based on its estimates.

 This patch only commits the target independent framework that evaluates
 and selects code sequences. The machine instruction combiner is turned
 off for all targets and expected to evolve over time by gradually
 handling DAGCombiner pattern in the target specific code.

 This framework lays the groundwork for fixing
 rdar://16319955



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214666 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-03 21:35:39 +00:00
James Molloy
e411c38de9 [AArch64] Teach DAGCombiner that converting two consecutive loads into a vector load is not a good transform when paired loads are available.
The combiner was creating Q-register loads and stores, which then had to be spilled because there are no callee-save Q registers!



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214634 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-02 14:51:24 +00:00
Chandler Carruth
4e6635e7e6 [SDAG] Refactor the code which deletes nodes in the DAG combiner to do
so using a single helper which adds operands back onto the worklist.

Several places didn't rigorously do this but a couple already did.
Factoring them together and doing it rigorously is important to delete
things recursively early on in the combiner and get a chance to see
accurate hasOneUse values. While no existing test cases change, an
upcoming patch to add DAG combining logic for PSHUFB requires this to
work correctly.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214623 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-02 10:02:07 +00:00
Owen Anderson
ec6d4d8afb Fix issues with ISD::FNEG and ISD::FMA SDNodes where they would not be constant-folded
during DAGCombine in certain circumstances.  Unfortunately, the circumstances required
to trigger the issue seem to require a pretty specific interaction of DAGCombines,
and I haven't been able to find a testcase that reproduces on X86, ARM, or AArch64.
The functionality added here is replicated in essentially every other DAG combine,
so it seems pretty obviously correct.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214622 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-02 08:45:33 +00:00
Justin Bogner
61e99f1b80 CodeGen: Remove commented out code
These two lines have been commented out for over 4 years. They aren't
helping anyone.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214615 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-02 06:47:07 +00:00
Adrian Prantl
87c17d97f3 Attempt to increase the overall happiness of the MSCV-based buildbots.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214588 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-01 22:56:10 +00:00
Adrian Prantl
2a39c993eb Debug info: Infrastructure to support debug locations for fragmented
variables (for example, by-value struct arguments passed in registers, or
large integer values split across several smaller registers).
On the IR level, this adds a new type of complex address operation OpPiece
to DIVariable that describes size and offset of a variable fragment.
On the DWARF emitter level, all pieces describing the same variable are
collected, sorted and emitted as DWARF expressions using the DW_OP_piece
and DW_OP_bit_piece operators.

http://reviews.llvm.org/D3373
rdar://problem/15928306

What this patch doesn't do / Future work:
- This patch only adds the backend machinery to make this work, patches
  that change SROA and SelectionDAG's type legalizer to actually create
  such debug info will follow. (http://reviews.llvm.org/D2680)
- Making the DIVariable complex expressions into an argument of dbg.value
  will reduce the memory footprint of the debug metadata.
- The sorting/uniquing of pieces should be moved into DebugLocEntry,
  to facilitate the merging of multi-piece entries.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214576 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-01 22:11:58 +00:00
Chandler Carruth
04395213ab [SDAG] MorphNodeTo recursively deletes dead operands of the old
fromulation of the node, which isn't really the desired behavior from
within the combiner or legalizer, but is necessary within ISel. I've
added a hopefully helpful comment and fixed the only two places where
this took place.

Yet another step toward the combiner and legalizer not needing to use
update listeners with virtual calls to manage the worklists behind
legalization and combining.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214574 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-01 22:09:43 +00:00