Commit Graph

1271 Commits

Author SHA1 Message Date
Sanjay Patel a260701bbb propagate fast-math-flags on DAG nodes
After D10403, we had FMF in the DAG but disabled by default. Nick reported no crashing errors after some stress testing, 
so I enabled them at r243687. However, Escha soon notified us of a bug not covered by any in-tree regression tests: 
if we don't propagate the flags, we may fail to CSE DAG nodes because differing FMF causes them to not match. There is
one test case in this patch to prove that point.

This patch hopes to fix or leave a 'TODO' for all of the in-tree places where we create nodes that are FMF-capable. I 
did this by putting an assert in SelectionDAG.getNode() to find any FMF-capable node that was being created without FMF
( D11807 ). I then ran all regression tests and test-suite and confirmed that everything passes.

This patch exposes remaining work to get DAG FMF to be fully functional: (1) add the flags to non-binary nodes such as
FCMP, FMA and FNEG; (2) add the flags to intrinsics; (3) use the flags as conditions for transforms rather than the
current global settings.

Differential Revision: http://reviews.llvm.org/D12095

llvm-svn: 247815
2015-09-16 16:31:21 +00:00
Matt Arsenault acd68b58ae SelectionDAG: Support Expand of f16 extloads
Currently this hits an assert that extload should
always be supported, which assumes integer extloads.

This moves a hack out of SI's argument lowering and
is covered by existing tests.

llvm-svn: 247113
2015-09-09 01:12:27 +00:00
Ahmed Bougacha f9c19da03a [CodeGen] Support (and default to) expanding READCYCLECOUNTER to 0.
For targets that didn't support this, this will let us respect the
langref instead of failing to select.

Note that we don't need to change the 32-bit x86/PPC lowerings (to
account for the result type/# difference) because they're both
custom and bypass type legalization.

llvm-svn: 246258
2015-08-28 01:49:59 +00:00
Charles Davis 119525914c Make variable argument intrinsics behave correctly in a Win64 CC function.
Summary:
This change makes the variable argument intrinsics, `llvm.va_start` and
`llvm.va_copy`, and the `va_arg` instruction behave as they do on Windows
inside a `CallingConv::X86_64_Win64` function. It's needed for a Clang patch
I have to add support for GCC's `__builtin_ms_va_list` constructs.

Reviewers: nadav, asl, eugenis

CC: llvm-commits

Differential Revision: http://llvm-reviews.chandlerc.com/D1622

llvm-svn: 245990
2015-08-25 23:27:41 +00:00
Ahmed Bougacha a196661bb0 [CodeGen] Mark the promoted FCOPYSIGN result FP_ROUND as TRUNCating.
Now that we can properly promote mismatched FCOPYSIGNs (r244858), we
can mark the FP_ROUND on the result as truncating, to expose folding.

FCOPYSIGN doesn't change anything but the sign bit, so
  (fp_round (fcopysign (fpext a), b))
is equivalent to (modulo the sign bit):
  (fp_round (fpext a))
which is a no-op.

llvm-svn: 244862
2015-08-13 01:32:30 +00:00
Ahmed Bougacha 40ded502ff [CodeGen] When Promoting, don't extend the 2nd FCOPYSIGN operand.
We don't care about its type, and there's even a combine that'll fold
away the FP_EXTEND if we let it run. However, until it does, we'll have
something broken like:
  (f32 (fp_extend (f64 v)))

Scalar f16 follow-up to r243924.

llvm-svn: 244858
2015-08-13 01:09:43 +00:00
Alex Lorenz e40c8a2b26 PseudoSourceValue: Replace global manager with a manager in a machine function.
This commit removes the global manager variable which is responsible for
storing and allocating pseudo source values and instead it introduces a new
manager class named 'PseudoSourceValueManager'. Machine functions now own an
instance of the pseudo source value manager class.

This commit also modifies the 'get...' methods in the 'MachinePointerInfo'
class to construct pseudo source values using the instance of the pseudo
source value manager object from the machine function.

This commit updates calls to the 'get...' methods from the 'MachinePointerInfo'
class in a lot of different files because those calls now need to pass in a
reference to a machine function to those methods.

This change will make it easier to serialize pseudo source values as it will
enable me to transform the mips specific MipsCallEntry PseudoSourceValue
subclass into two target independent subclasses.

Reviewers: Akira Hatanaka
llvm-svn: 244693
2015-08-11 23:09:45 +00:00
Hal Finkel caf1149b8b [SDAG] Fix a result chain in ExpandUnalignedLoad
On the code path in ExpandUnalignedLoad which expands an unaligned vector/fp
value in terms of a legal integer load of the same size, the ChainResult needs
to be the chain result of the integer load.

No in-tree test case is currently available.

Patch by Jan Hranac!

llvm-svn: 243956
2015-08-04 06:29:12 +00:00
Sanjay Patel 0f9dcf8b90 move DAGCombiner's allowableAlignment() helper function into the TLI
Making allowableAlignment() more accessible was suggested as a predecessor patch
for D10662, so I've pulled it into TargetLowering. This let's us remove 4 instances
of duplicate logic in LegalizeDAG.

There's a subtle functional change in the implementation: the existing 
allowableAlignment() code was using getPrefTypeAlignment() when checking 
alignment with the DataLayout and assumed that was fast. In this implementation,
we use getABITypeAlignment() and assume that is fast. See the TODO comment or the
discussion in the Phab review for future improvements in this implementation
(don't use the data layout at all).

There are no regression test changes from this difference, and I'm not sure how to
expose it via a test. I think we actually do want to provide the 'Fast' param when
checking this from DAGCombiner::MergeConsecutiveStores(). Ie, we shouldn't merge 
stores if the new stores are not going to be fast. But that change will require 
fixing allowsMisalignedMemoryAccess() overrides as noted in D10662.

Differential Revision: http://reviews.llvm.org/D10905

llvm-svn: 243549
2015-07-29 18:24:18 +00:00
Matthias Braun 3cd00c1739 Fix __builtin_setjmp in combination with sjlj exception handling.
llvm.eh.sjlj.setjmp was used as part of the SjLj exception handling
style but is also used in clang to implement __builtin_setjmp.  The ARM
backend needs to output additional dispatch tables for the SjLj
exception handling style, these tables however can't be emitted if
llvm.eh.sjlj.setjmp is simply used for __builtin_setjmp and no actual
landing pad blocks exist.

To solve this issue a new llvm.eh.sjlj.setup_dispatch intrinsic is
introduced which is used instead of llvm.eh.sjlj.setjmp in the SjLj
exception handling lowering, so we can differentiate between the case
where we actually need to setup a dispatch table and the case where we
just need the __builtin_setjmp semantic.

Differential Revision: http://reviews.llvm.org/D9313

llvm-svn: 242481
2015-07-16 22:34:16 +00:00
Pete Cooper 8acd386969 Use getZExtOrTrunc helper instead of manually doing zext/trunc check. NFC.
The code here was doing exactly what is already in getZExtOrTrunc().
Just use that method instead.

llvm-svn: 242260
2015-07-15 00:43:54 +00:00
Matthias Braun 75e668ea6e Revert "LegalizeDAG: Fix and improve FCOPYSIGN/FABS legalization"
Accidental commit, needs review first.

This reverts commit r242107.

llvm-svn: 242108
2015-07-14 02:09:57 +00:00
Matthias Braun 4ac4ecdadf LegalizeDAG: Fix and improve FCOPYSIGN/FABS legalization
- Factor out code to query and modify the sign bit of a floatingpoint
  value as an integer. This also works if none of the targets integer
  types is big enough to hold all bits of the floatingpoint value.

- Legalize FABS(x) as FCOPYSIGN(x, 0.0) if FCOPYSIGN is available,
  otherwise perform bit manipulation on the sign bit. The previous code
  used "x >u 0 ? x : -x" which is incorrect for x being -0.0! It also
  takes 34 instructions on ARM Cortex-M4. With this patch we only
  require 5:
    vldr d0, LCPI0_0
    vmov r2, r3, d0
    lsrs r2, r3, #31
    bfi r1, r2, #31, #1
    bx lr
  (This could be further improved if the compiler would recognize that
   r2, r3 is zero).

- Only lower FCOPYSIGN(x, y) = sign(x) ? -FABS(x) : FABS(x) if FABS is
  available otherwise perform bit manipulation on the sign bit.

- Perform the sign(x) test by masking out the sign bit and comparing
  with 0 rather than shifting the sign bit to the highest position and
  testing for "<s 0". For x86 copysignl (on 80bit values) this gets us:
    testl $32768, %eax
  rather than:
    shlq $48, %rax
    sets %al
    testb %al, %al

llvm-svn: 242107
2015-07-14 02:08:26 +00:00
Mehdi Amini 9639d650bb Make TargetLowering::getShiftAmountTy() taking DataLayout as an argument
Summary:
This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.

Reviewers: echristo

Subscribers: jholewinski, llvm-commits, rafael, yaron.keren

Differential Revision: http://reviews.llvm.org/D11037

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 241776
2015-07-09 02:09:20 +00:00
Mehdi Amini 44ede33a69 Make TargetLowering::getPointerTy() taking DataLayout as an argument
Summary:
This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.

Reviewers: echristo

Subscribers: jholewinski, ted, yaron.keren, rafael, llvm-commits

Differential Revision: http://reviews.llvm.org/D11028

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 241775
2015-07-09 02:09:04 +00:00
Mehdi Amini 8ac7a9d57a Redirect DataLayout from TargetMachine to Module in SelectionDAG
Summary:
SelectionDAG itself is not invoking directly the DataLayout in the
TargetMachine, but the "TargetLowering" class is still using it. I'll
address it in a following commit.

This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.

Reviewers: echristo

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D11000

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 241618
2015-07-07 19:07:19 +00:00
Pete Cooper af61ac71e2 Wrap assert loops in #ifndef NDEBUG
The body of the loops here only contained asserts.  This triggered an unused variable
warning on release builds and -Werror on the bots.

llvm-svn: 240819
2015-06-26 19:23:20 +00:00
Pete Cooper 8fc121dfc4 Convert a bunch of loops to foreach. NFC.
This uses the new SDNode::op_values() iterator range committed in r240805.

llvm-svn: 240815
2015-06-26 19:08:33 +00:00
Alexander Kornienko f00654e31b Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC)
Apparently, the style needs to be agreed upon first.

llvm-svn: 240390
2015-06-23 09:49:53 +00:00
Alexander Kornienko 70bc5f1398 Fixed/added namespace ending comments using clang-tidy. NFC
The patch is generated using this command:

tools/clang/tools/extra/clang-tidy/tool/run-clang-tidy.py -fix \
  -checks=-*,llvm-namespace-comment -header-filter='llvm/.*|clang/.*' \
  llvm/lib/


Thanks to Eugene Kosov for the original patch!

llvm-svn: 240137
2015-06-19 15:57:42 +00:00
James Molloy 7e9776b559 Add SDNodes for umin, umax, smin and smax.
This adds new SDNodes for signed/unsigned min/max. These nodes are built from
select/icmp pairs matched at SDAGBuilder stage.

This patch adds the nodes, as well as legalization support and sets them to
be "expand" for all targets.

NFC for now; this will be tested when I switch AArch64 to using these new
nodes.

llvm-svn: 237423
2015-05-15 09:03:15 +00:00
Eric Christopher 824f42f209 Migrate existing backends that care about software floating point
to use the information in the module rather than TargetOptions.

We've had and clang has used the use-soft-float attribute for some
time now so have the backends set a subtarget feature based on
a particular function now that subtargets are created based on
functions and function attributes.

For the one middle end soft float check go ahead and create
an overloadable TargetLowering::useSoftFloat function that
just checks the TargetSubtargetInfo in all cases.

Also remove the command line option that hard codes whether or
not soft-float is set by using the attribute for all of the
target specific test cases - for the generic just go ahead and
add the attribute in the one case that showed up.

llvm-svn: 237079
2015-05-12 01:26:05 +00:00
Jan Vesely 7539548738 CodeGen: Default overflow operations to expand so we don't have to assume targets are lying
Signed-off-by: Jan Vesely <jan.vesely@rutgers.edu>
Reviewed-by: ab
Differential Revision: http://reviews.llvm.org/D9265

llvm-svn: 236119
2015-04-29 16:30:46 +00:00
Sergey Dmitrouk 842a51bad8 Reapply r235977 "[DebugInfo] Add debug locations to constant SD nodes"
[DebugInfo] Add debug locations to constant SD nodes

This adds debug location to constant nodes of Selection DAG and updates
all places that create constants to pass debug locations
(see PR13269).

Can't guarantee that all locations are correct, but in a lot of cases choice
is obvious, so most of them should be. At least all tests pass.

Tests for these changes do not cover everything, instead just check it for
SDNodes, ARM and AArch64 where it's easy to get incorrect locations on
constants.

This is not complete fix as FastISel contains workaround for wrong debug
locations, which drops locations from instructions on processing constants,
but there isn't currently a way to use debug locations from constants there
as llvm::Constant doesn't cache it (yet). Although this is a bit different
issue, not directly related to these changes.

Differential Revision: http://reviews.llvm.org/D9084

llvm-svn: 235989
2015-04-28 14:05:47 +00:00
Daniel Jasper 48e93f7181 Revert "[DebugInfo] Add debug locations to constant SD nodes"
This breaks a test:
http://bb.pgr.jp/builders/cmake-llvm-x86_64-linux/builds/23870

llvm-svn: 235987
2015-04-28 13:38:35 +00:00
Sergey Dmitrouk adb4c69d5c [DebugInfo] Add debug locations to constant SD nodes
This adds debug location to constant nodes of Selection DAG and updates
all places that create constants to pass debug locations
(see PR13269).

Can't guarantee that all locations are correct, but in a lot of cases choice
is obvious, so most of them should be. At least all tests pass.

Tests for these changes do not cover everything, instead just check it for
SDNodes, ARM and AArch64 where it's easy to get incorrect locations on
constants.

This is not complete fix as FastISel contains workaround for wrong debug
locations, which drops locations from instructions on processing constants,
but there isn't currently a way to use debug locations from constants there
as llvm::Constant doesn't cache it (yet). Although this is a bit different
issue, not directly related to these changes.

Differential Revision: http://reviews.llvm.org/D9084

llvm-svn: 235977
2015-04-28 11:56:37 +00:00
Ahmed Bougacha 1ffe7c7d36 [AArch64] Promote f16 operations to f32.
For the most common ones (such as fadd), we already did the promotion.
Do the same thing for all the others.

Currently, we'll just crash/assert on all these operations, as
there's no hardware or libcall support whatsoever.

f16 (half) is specified as an interchange - not arithmetic - format,
and is expected to be promoted to single-precision for arithmetic
operations.

While there, teach the legalizer about promoting some of the (mostly
floating-point) operations that we never needed before.

Differential Revision: http://reviews.llvm.org/D8648
See related discussion on the thread for: http://reviews.llvm.org/D8755

llvm-svn: 234550
2015-04-10 00:08:48 +00:00
Ahmed Bougacha c809761dc0 [CodeGen] Replace the reused stores' chain for extractelt expansion.
This fixes a subtle issue that was introduced in r205153.

When reusing a store for the extractelement expansion (to load directly
from it, inserting of going through the stack), later stores to the
same location might have overwritten the data we were expecting to
extract from.

To fix that, we need to explicitly replace the chain going out of the
reused store, so that later stores also have an explicit dependency on
the generated element-extracting loads, and can't clobber them.

rdar://20066785
Differential Revision: http://reviews.llvm.org/D8180

llvm-svn: 231721
2015-03-09 22:51:05 +00:00
Benjamin Kramer c54c38e090 SDAG: Merge the meat of two ExpandAtomic implementations.
The copies already diverged, don't let them become any worse. Reduce
redundancy in code with a little macro metaprogramming.

llvm-svn: 231401
2015-03-05 20:04:29 +00:00
Hal Finkel cec70130ac [SDAG] Handle LowerOperation returning its input consistently
For almost all node types, if the target requested custom lowering, and
LowerOperation returned its input, we'd treat the original node as legal. This
did not work, however, for many loads and stores, because they follow
slightly different code paths, and we did not account for the possibility of
LowerOperation returning its input at those call sites.

I think that we now handle this consistently everywhere. At the call sites in
LegalizeDAG, we used to assert in this case, so there's no functional change
for any existing code there. For the call sites in LegalizeVectorOps, this
really only affects whether or not we set Changed = true, but I think makes the
semantics clearer.

No test case here, but it will be covered by an upcoming PowerPC commit adding
QPX support.

llvm-svn: 230332
2015-02-24 12:59:47 +00:00
Andrea Di Biagio af3f397b10 [X86] Teach how to custom lower double-to-half conversions under fast-math.
This patch teaches the backend how to expand a double-half conversion into
a double-float conversion immediately followed by a float-half conversion.
We do this only under fast-math, and if float-half conversions are legal
for the target.

Added test CodeGen/X86/fastmath-float-half-conversion.ll

Differential Revision: http://reviews.llvm.org/D7832

llvm-svn: 230276
2015-02-23 22:59:02 +00:00
Matt Arsenault 0dc54c4dee Add generic fmad DAG node.
This allows sharing of FMA forming combines to work
with instructions that have the same semantics as a separate
multiply and add.

This is expand by default, and only formed post legalization
so it shouldn't have much impact on targets that do not want it.

llvm-svn: 230070
2015-02-20 22:10:33 +00:00
Matt Arsenault bd22342322 Implement new way of expanding extloads.
Now that the source and destination types can be specified,
allow doing an expansion that doesn't use an EXTLOAD of the
result type. Try to do a legal extload to an intermediate type
and extend that if possible.

This generalizes the special case custom lowering of extloads
R600 has been using to work around this problem.

This also happens to fix a bug that would incorrectly use more
aligned loads than should be used.

llvm-svn: 225925
2015-01-14 01:35:17 +00:00
Ahmed Bougacha 2b6917b020 [SelectionDAG] Allow targets to specify legality of extloads' result
type (in addition to the memory type).

The *LoadExt* legalization handling used to only have one type, the
memory type.  This forced users to assume that as long as the extload
for the memory type was declared legal, and the result type was legal,
the whole extload was legal.

However, this isn't always the case.  For instance, on X86, with AVX,
this is legal:
    v4i32 load, zext from v4i8
but this isn't:
    v4i64 load, zext from v4i8
Whereas v4i64 is (arguably) legal, even without AVX2.

Note that the same thing was done a while ago for truncstores (r46140),
but I assume no one needed it yet for extloads, so here we go.

Calls to getLoadExtAction were changed to add the value type, found
manually in the surrounding code.

Calls to setLoadExtAction were mechanically changed, by wrapping the
call in a loop, to match previous behavior.  The loop iterates over
the MVT subrange corresponding to the memory type (FP vectors, etc...).
I also pulled neighboring setTruncStoreActions into some of the loops;
those shouldn't make a difference, as the additional types are illegal.
(e.g., i128->i1 truncstores on PPC.)

No functional change intended.

Differential Revision: http://reviews.llvm.org/D6532

llvm-svn: 225421
2015-01-08 00:51:32 +00:00
Sanjay Patel eb4a4d5aeb Don't repeat class/function/variable names in comments. NFC.
llvm-svn: 222555
2014-11-21 18:58:38 +00:00
Sanjay Patel b06441aded Less space; NFC
llvm-svn: 222546
2014-11-21 18:05:59 +00:00
David Blaikie 70573dcd9f Update SetVector to rely on the underlying set's insert to return a pair<iterator, bool>
This is to be consistent with StringSet and ultimately with the standard
library's associative container insert function.

This lead to updating SmallSet::insert to return pair<iterator, bool>,
and then to update SmallPtrSet::insert to return pair<iterator, bool>,
and then to update all the existing users of those functions...

llvm-svn: 222334
2014-11-19 07:49:26 +00:00
Owen Anderson b5a259935c Fix an incorrect chain operand when expanding INSERT_VECTOR operations through the stack.
Patch by Daniil Troshkov!

llvm-svn: 222254
2014-11-18 20:50:19 +00:00
Matt Arsenault 7c93690be0 Add minnum / maxnum codegen
llvm-svn: 220342
2014-10-21 23:01:01 +00:00
Eric Christopher 85de8f98a9 Use the subtarget on the dag to get TargetFrameLowering rather
than off the target machine.

llvm-svn: 219378
2014-10-09 01:35:27 +00:00
Benjamin Kramer c6cc58e703 Remove unnecessary copying or replace it with moves in a bunch of places.
NFC.

llvm-svn: 219061
2014-10-04 16:55:56 +00:00
Sanjay Patel bb29221129 Replace dead links to "Hacker's Delight" with general references. NFC.
llvm-svn: 217814
2014-09-15 19:47:44 +00:00
Chandler Carruth 74ec9e19ee [SDAG] Re-instate r215611 with a fix to a pesky X86 DAG combine.
This combine is essentially combining target-specific nodes back into target
independent nodes that it "knows" will be combined yet again by a target
independent DAG combine into a different set of target-independent nodes that
are legal (not custom though!) and thus "ok". This seems... deeply flawed. The
crux of the problem is that we don't combine un-legalized shuffles that are
introduced by legalizing other operations, and thus we don't see a very
profitable combine opportunity. So the backend just forces the input to that
combine to re-appear.

However, for this to work, the conditions detected to re-form the unlegalized
nodes must be *exactly* right. Previously, failing this would have caused poor
code (if you're lucky) or a crasher when we failed to select instructions.
After r215611 we would fall back into the legalizer. In some cases, this just
"fixed" the crasher by produces bad code. But in the test case added it caused
the legalizer and the dag combiner to iterate forever.

The fix is to make the alignment checking in the x86 side of things match the
alignment checking in the generic DAG combine exactly. This isn't really a
satisfying or principled fix, but it at least make the code work as intended.
It also highlights that it would be nice to detect the availability of under
aligned loads for a given type rather than bailing on this optimization. I've
left a FIXME to document this.

Original commit message for r215611 which covers the rest of the chang:
  [SDAG] Fix a case where we would iteratively legalize a node during
  combining by replacing it with something else but not re-process the
  node afterward to remove it.

  In a truly remarkable stroke of bad luck, this would (in the test case
  attached) end up getting some other node combined into it without ever
  getting re-processed. By adding it back on to the worklist, in addition
  to deleting the dead nodes more quickly we also ensure that if it
  *stops* being dead for any reason it makes it back through the
  legalizer. Without this, the test case will end up failing during
  instruction selection due to an and node with a type we don't have an
  instruction pattern for.

It took many million runs of the shuffle fuzz tester to find this.

llvm-svn: 216537
2014-08-27 11:22:16 +00:00
Nick Lewycky a4967c2740 Revert r215611 because it caused the infinite loop in bug 20736. There is a reduced testcase in that bug.
llvm-svn: 216307
2014-08-23 00:45:03 +00:00
Oliver Stannard 51b1d460cb [ARM] Enable DP copy, load and store instructions for FPv4-SP
The FPv4-SP floating-point unit is generally referred to as
single-precision only, but it does have double-precision registers and
load, store and GPR<->DPR move instructions which operate on them.
This patch enables the use of these registers, the main advantage of
which is that we now comply with the AAPCS-VFP calling convention.
This partially reverts r209650, which added some AAPCS-VFP support,
but did not handle return values or alignment of double arguments in
registers.

This patch also adds tests for Thumb2 code generation for
floating-point instructions and intrinsics, which previously only
existed for ARM.

llvm-svn: 216172
2014-08-21 12:50:31 +00:00
Oliver Stannard f5469bec97 Teach the AArch64 backend to handle f16
This allows the AArch64 backend to handle fadd, fsub, fmul and fdiv
operations on f16 (half-precision) types by promoting to f32.

llvm-svn: 215891
2014-08-18 14:22:39 +00:00
Chandler Carruth 8039b16de7 [SDAG] Fix a case where we would iteratively legalize a node during
combining by replacing it with something else but not re-process the
node afterward to remove it.

In a truly remarkable stroke of bad luck, this would (in the test case
attached) end up getting some other node combined into it without ever
getting re-processed. By adding it back on to the worklist, in addition
to deleting the dead nodes more quickly we also ensure that if it
*stops* being dead for any reason it makes it back through the
legalizer. Without this, the test case will end up failing during
instruction selection due to an and node with a type we don't have an
instruction pattern for.

It took many million runs of the shuffle fuzz tester to find this.

llvm-svn: 215611
2014-08-14 01:07:37 +00:00
Eric Christopher d913448b38 Remove the TargetMachine forwards for TargetSubtargetInfo based
information and update all callers. No functional change.

llvm-svn: 214781
2014-08-04 21:25:23 +00:00
Chandler Carruth 1f52b3da0a [SDAG] Begin simplifying the way in which the legalizer deletes nodes.
This lifts the (very few) places the legalizer would delete dead nodes
into the outer loop around the legalizer. This is significantly simpler
because it doesn't require the legalizer itself to manage the iterator
validity, and it doesn't require the legalizer to be a DAG update
listener in order to remove things from the legalized set. It also makes
the interface much less contrived for the case of the legalizer running
inside the last phase of DAG combining.

I'm working on centralizing the deletion of nodes during both legalizing
and combining as much as possible. My hope is to remove the need for DAG
update listeners from the combiner next, which would remove a costly
virtual dispatch chain on every deletion. This in turn should allow us
to more aggressively delete DAG nodes during combining which will in
turn allow us to combine more aggressively by exposing the actual nodes
which have single users to the combine phases.

llvm-svn: 214546
2014-08-01 19:49:59 +00:00
Louis Gerbarg 67474e3755 Make sure no loads resulting from load->switch DAGCombine are marked invariant
Currently when DAGCombine converts loads feeding a switch into a switch of
addresses feeding a load the new load inherits the isInvariant flag of the left
side. This is incorrect since invariant loads can be reordered in cases where it
is illegal to reoarder normal loads.

This patch adds an isInvariant parameter to getExtLoad() and updates all call
sites to pass in the data if they have it or false if they don't. It also
changes the DAGCombine to use that data to make the right decision when
creating the new load.

llvm-svn: 214449
2014-07-31 21:45:05 +00:00