Commit Graph

20 Commits

Author SHA1 Message Date
Nirav Dave
ca6d3f8f6a [DAG] Improve Aliasing of operations to static alloca
Re-recommiting after landing DAG extension-crash fix.

Recommiting after adding check to avoid miscomputing alias information
on addresses of the same base but different subindices.

Memory accesses offset from frame indices may alias, e.g., we
may merge write from function arguments passed on the stack when they
are contiguous. As a result, when checking aliasing, we consider the
underlying frame index's offset from the stack pointer.

Static allocs are realized as stack objects in SelectionDAG, but its
offset is not set until post-DAG causing DAGCombiner's alias check to
consider access to static allocas to frequently alias. Modify isAlias
to consider access between static allocas and access from other frame
objects to be considered aliasing.

Many test changes are included here. Most are fixes for tests which
indirectly relied on our aliasing ability and needed to be modified to
preserve their original intent.

The remaining tests have minor improvements due to relaxed
ordering. The exception is CodeGen/X86/2011-10-19-widen_vselect.ll
which has a minor degradation dispite though the pre-legalized DAG is
improved.

Reviewers: rnk, mkuper, jonpa, hfinkel, uweigand

Reviewed By: rnk

Subscribers: sdardis, nemanjai, javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D33345

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@308350 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-18 20:06:24 +00:00
Chandler Carruth
98e77572bc Revert r308025 due to uncovering a crash in SelectionDAG. This is filed
with a minimal test case in http://llvm.org/PR33833.

Original commit message:
  Improve Aliasing of operations to static alloca

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@308271 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-18 07:53:47 +00:00
Nirav Dave
be4d3e6292 Improve Aliasing of operations to static alloca
Recommiting after adding check to avoid miscomputing alias information
on addresses of the same base but different subindices.

Memory accesses offset from frame indices may alias, e.g., we
may merge write from function arguments passed on the stack when they
are contiguous. As a result, when checking aliasing, we consider the
underlying frame index's offset from the stack pointer.

Static allocs are realized as stack objects in SelectionDAG, but its
offset is not set until post-DAG causing DAGCombiner's alias check to
consider access to static allocas to frequently alias. Modify isAlias
to consider access between static allocas and access from other frame
objects to be considered aliasing.

Many test changes are included here. Most are fixes for tests which
indirectly relied on our aliasing ability and needed to be modified to
preserve their original intent.

The remaining tests have minor improvements due to relaxed
ordering. The exception is CodeGen/X86/2011-10-19-widen_vselect.ll
which has a minor degradation dispite though the pre-legalized DAG is
improved.

Reviewers: rnk, mkuper, jonpa, hfinkel, uweigand

Reviewed By: rnk

Subscribers: sdardis, nemanjai, javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D33345

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@308025 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-14 13:56:21 +00:00
Matthias Braun
c364d94de8 Revert "[DAG] Improve Aliasing of operations to static alloca"
Reverting as it breaks tramp3d-v4 in the llvm test-suite. I added some
comments to https://reviews.llvm.org/D33345 about it.

This reverts commit r307546.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307589 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-10 20:51:30 +00:00
Nirav Dave
e791f411d3 [DAG] Improve Aliasing of operations to static alloca
Memory accesses offset from frame indices may alias, e.g., we
may merge write from function arguments passed on the stack when they
are contiguous. As a result, when checking aliasing, we consider the
underlying frame index's offset from the stack pointer.

Static allocs are realized as stack objects in SelectionDAG, but its
offset is not set until post-DAG causing DAGCombiner's alias check to
consider access to static allocas to frequently alias. Modify isAlias
to consider access between static allocas and access from other frame
objects to be considered aliasing.

Many test changes are included here. Most are fixes for tests which
indirectly relied on our aliasing ability and needed to be modified to
preserve their original intent.

The remaining tests have minor improvements due to relaxed
ordering. The exception is CodeGen/X86/2011-10-19-widen_vselect.ll
which has a minor degradation dispite though the pre-legalized DAG is
improved.

Reviewers: rnk, mkuper, jonpa, hfinkel, uweigand

Reviewed By: rnk

Subscribers: sdardis, nemanjai, javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D33345

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307546 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-10 15:39:41 +00:00
Daniel Jasper
7da5231e32 Revert "r306529 - [X86] Correct dwarf unwind information in function epilogue"
I am 99% sure that this breaks the PPC ASAN build bot:
http://lab.llvm.org:8011/builders/sanitizer-ppc64be-linux/builds/3112/steps/64-bit%20check-asan/logs/stdio

If it doesn't go back to green, we can recommit (and fix the original
commit message at the same time :) ).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@306676 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-29 13:58:24 +00:00
Petar Jovanovic
32d37d6720 [X86] Correct dwarf unwind information in function epilogue
CFI instructions that set appropriate cfa offset and cfa register are now
inserted in emitEpilogue() in X86FrameLowering.

Majority of the changes in this patch:

1. Ensure that CFI instructions do not affect code generation.
2. Enable maintaining correct information about cfa offset and cfa register
in a function when basic blocks are reordered, merged, split, duplicated.

These changes are target independent and described below.

Changed CFI instructions so that they:

1. are duplicable
2. are not counted as instructions when tail duplicating or tail merging
3. can be compared as equal

Add information to each MachineBasicBlock about cfa offset and cfa register
that are valid at its entry and exit (incoming and outgoing CFI info). Add
support for updating this information when basic blocks are merged, split,
duplicated, created. Add a verification pass (CFIInfoVerifier) that checks
that outgoing cfa offset and register of predecessor blocks match incoming
values of their successors.

Incoming and outgoing CFI information is used by a late pass
(CFIInstrInserter) that corrects CFA calculation rule for a basic block if
needed. That means that additional CFI instructions get inserted at basic
block beginning to correct the rule for calculating CFA. Having CFI
instructions in function epilogue can cause incorrect CFA calculation rule
for some basic blocks. This can happen if, due to basic block reordering,
or the existence of multiple epilogue blocks, some of the blocks have wrong
cfa offset and register values set by the epilogue block above them.

Patch by Violeta Vukobrat.

Differential Revision: https://reviews.llvm.org/D18046


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@306529 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-28 10:21:17 +00:00
Philip Reames
bfffaf778f Add placeholder for more extensive verification of psuedo ops
This initial patch doesn't actually do much useful. It's just to show where the new code goes. Once this is in, I'll extend the verification logic to check more useful properties.

For those curious, the more complicated version of this patch already found one very suspicious thing.

Differential Revision: https://reviews.llvm.org/D33819



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@304564 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-02 16:36:37 +00:00
Dan Gohman
f4e788949d [MC] Use .p2align instead of .align
For historic reasons, the behavior of .align differs between targets.
Fortunately, there are alternatives, .p2align and .balign, which make the
interpretation of the parameter explicit, and which behave consistently across
targets.

This patch teaches MC to use .p2align instead of .align, so that people reading
code for multiple architectures don't have to remember which way each platform
does its .align directive.

Differential Revision: http://reviews.llvm.org/D16549


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@258750 91177308-0d34-0410-b5e6-96231b3b80d8
2016-01-26 00:03:25 +00:00
Chen Li
955318d58d [gc.statepoint] Change gc.statepoint intrinsic's return type to token type instead of i32 type
Summary: This patch changes gc.statepoint intrinsic's return type to token type instead of i32 type. Using token types could prevent LLVM to merge different gc.statepoint nodes into PHI nodes and cause further problems with gc relocations. The patch also changes the way on how gc.relocate and gc.result look for their corresponding gc.statepoint on unwind path. The current implementation uses the selector value extracted from a { i8*, i32 } landingpad as a hook to find the gc.statepoint, while the patch directly uses a token type landingpad (http://reviews.llvm.org/D15405) to find the gc.statepoint. 

Reviewers: sanjoy, JosephTremoulet, pgavlin, igor-laevsky, mjacob

Subscribers: reames, mjacob, sanjoy, llvm-commits

Differential Revision: http://reviews.llvm.org/D15662

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256443 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-26 07:54:32 +00:00
Jonathan Roelofs
993a1116f7 Fix a bunch of trivial cases of 'CHECK[^:]*$' in the tests. NFCI
I looked into adding a warning / error for this to FileCheck, but there doesn't
seem to be a good way to avoid it triggering on the instances of it in RUN lines.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@244481 91177308-0d34-0410-b5e6-96231b3b80d8
2015-08-10 19:01:27 +00:00
David Majnemer
cc714e2142 Move the personality function from LandingPadInst to Function
The personality routine currently lives in the LandingPadInst.

This isn't desirable because:
- All LandingPadInsts in the same function must have the same
  personality routine.  This means that each LandingPadInst beyond the
  first has an operand which produces no additional information.

- There is ongoing work to introduce EH IR constructs other than
  LandingPadInst.  Moving the personality routine off of any one
  particular Instruction and onto the parent function seems a lot better
  than have N different places a personality function can sneak onto an
  exceptional function.

Differential Revision: http://reviews.llvm.org/D10429

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239940 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-17 20:52:32 +00:00
Igor Laevsky
efab5a1dfa [StatepointLowering] Support of the gc.relocates for invoke statepoints.
This change implements support for lowering of the gc.relocates tied to the invoke statepoint.
This is acomplished by storing frame indices of the lowered values in "StatepointRelocatedValues" map inside FunctionLoweringInfo instead of storing them in per-basic block structure StatepointLowering.
After this change StatepointLowering is used only during "LowerStatepoint" call and it is not necessary to store it as a field in SelectionDAGBuilder anymore.

Differential Revision: http://reviews.llvm.org/D7798


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237786 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-20 11:37:25 +00:00
Sanjoy Das
ead2d1fbe0 [Statepoints] Support for "patchable" statepoints.
Summary:
This change adds two new parameters to the statepoint intrinsic, `i64 id`
and `i32 num_patch_bytes`.  `id` gets propagated to the ID field
in the generated StackMap section.  If the `num_patch_bytes` is
non-zero then the statepoint is lowered to `num_patch_bytes` bytes of
nops instead of a call (the spill and reload code remains unchanged).
A non-zero `num_patch_bytes` is useful in situations where a language
runtime requires complete control over how a call is lowered.

This change brings statepoints one step closer to patchpoints.  With
some additional work (that is not part of this patch) it should be
possible to get rid of `TargetOpcode::STATEPOINT` altogether.

PlaceSafepoints generates `statepoint` wrappers with `id` set to
`0xABCDEF00` (the old default value for the ID reported in the stackmap)
and `num_patch_bytes` set to `0`.  This can be made more sophisticated
later.

Reviewers: reames, pgavlin, swaroop.sridhar, AndyAyers

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D9546

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237214 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-12 23:52:24 +00:00
Pat Gavlin
5c7f7462e4 Extend the statepoint intrinsic to allow statepoints to be marked as transitions from GC-aware code to code that is not GC-aware.
This changes the shape of the statepoint intrinsic from:

  @llvm.experimental.gc.statepoint(anyptr target, i32 # call args, i32 unused, ...call args, i32 # deopt args, ...deopt args, ...gc args)

to:

  @llvm.experimental.gc.statepoint(anyptr target, i32 # call args, i32 flags, ...call args, i32 # transition args, ...transition args, i32 # deopt args, ...deopt args, ...gc args)

This extension offers the backend the opportunity to insert (somewhat) arbitrary code to manage the transition from GC-aware code to code that is not GC-aware and back.

In order to support the injection of transition code, this extension wraps the STATEPOINT ISD node generated by the usual lowering lowering with two additional nodes: GC_TRANSITION_START and GC_TRANSITION_END. The transition arguments that were passed passed to the intrinsic (if any) are lowered and provided as operands to these nodes and may be used by the backend during code generation.

Eventually, the lowering of the GC_TRANSITION_{START,END} nodes should be informed by the GC strategy in use for the function containing the intrinsic call; for now, these nodes are instead replaced with no-ops.

Differential Revision: http://reviews.llvm.org/D9501

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236888 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-08 18:07:42 +00:00
David Blaikie
e41f3849bc [opaque pointer type] Add textual IR support for explicit type parameter to the invoke instruction
Same as r235145 for the call instruction - the justification, tradeoffs,
etc are all the same. The conversion script worked the same without any
false negatives (after replacing 'call' with 'invoke').

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235755 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-24 19:32:54 +00:00
Philip Reames
76acab3fc7 Require a GC strategy be specified for functions which use gc.statepoint
This was discussed a while back and I left it optional for migration.  Since it's been far more than the 'week or two' that was discussed, time to actually make this manditory.  



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233357 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-27 05:09:33 +00:00
Igor Laevsky
68beb2a9ec Teach lowering to correctly handle invoke statepoint and gc results tied to them. Note that we still can not lower gc.relocates for invoke statepoints.
Also it extracts getCopyFromRegs helper function in SelectionDAGBuilder as we need to be able to customize type of the register exported from basic block during lowering of the gc.result.
(Resubmitting this change after not being able to reproduce buildbot failure)

Differential Revision: http://reviews.llvm.org/D7760



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231800 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-10 16:26:48 +00:00
Igor Laevsky
684d323b9b Revert change r231366 as it broke clang-native-arm-cortex-a9 Analysis/properties.m test.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231374 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-05 15:41:14 +00:00
Igor Laevsky
f8b3003ab8 Teach lowering to correctly handle invoke statepoint and gc results tied to them. Note that we still can not lower gc.relocates for invoke statepoints.
Also it extracts getCopyFromRegs helper function in SelectionDAGBuilder as we need to be able to customize type of the register exported from basic block during lowering of the gc.result.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231366 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-05 14:11:21 +00:00