It turns out that terminatepad gives little benefit over a cleanuppad
which calls the termination function. This is not sufficient to
implement fully generic filters but MSVC doesn't support them which
makes terminatepad a little over-designed.
Depends on D15478.
Differential Revision: http://reviews.llvm.org/D15479
llvm-svn: 255522
While we have successfully implemented a funclet-oriented EH scheme on
top of LLVM IR, our scheme has some notable deficiencies:
- catchendpad and cleanupendpad are necessary in the current design
but they are difficult to explain to others, even to seasoned LLVM
experts.
- catchendpad and cleanupendpad are optimization barriers. They cannot
be split and force all potentially throwing call-sites to be invokes.
This has a noticable effect on the quality of our code generation.
- catchpad, while similar in some aspects to invoke, is fairly awkward.
It is unsplittable, starts a funclet, and has control flow to other
funclets.
- The nesting relationship between funclets is currently a property of
control flow edges. Because of this, we are forced to carefully
analyze the flow graph to see if there might potentially exist illegal
nesting among funclets. While we have logic to clone funclets when
they are illegally nested, it would be nicer if we had a
representation which forbade them upfront.
Let's clean this up a bit by doing the following:
- Instead, make catchpad more like cleanuppad and landingpad: no control
flow, just a bunch of simple operands; catchpad would be splittable.
- Introduce catchswitch, a control flow instruction designed to model
the constraints of funclet oriented EH.
- Make funclet scoping explicit by having funclet instructions consume
the token produced by the funclet which contains them.
- Remove catchendpad and cleanupendpad. Their presence can be inferred
implicitly using coloring information.
N.B. The state numbering code for the CLR has been updated but the
veracity of it's output cannot be spoken for. An expert should take a
look to make sure the results are reasonable.
Reviewers: rnk, JosephTremoulet, andrew.w.kaylor
Differential Revision: http://reviews.llvm.org/D15139
llvm-svn: 255422
Re-implement `ilist_node::getNextNode()` and `getPrevNode()` without
relying on the sentinel having a "next" pointer. Instead, get access to
the owning list and compare against the `begin()` and `end()` iterators.
This only works when the node *can* get access to the owning list. The
new support is in `ilist_node_with_parent<>`, and any class `Ty`
inheriting from `ilist_node<NodeTy>` that wants `getNextNode()` and/or
`getPrevNode()` should inherit from
`ilist_node_with_parent<NodeTy, ParentTy>` instead. The requirements:
- `NodeTy` must have a `getParent()` function that returns the parent.
- `ParentTy` must have a `getSublistAccess()` static that, given a(n
ignored) `NodeTy*` (to determine which list), returns a member field
pointer to the appropriate `ilist<>`.
This isn't the cleanest way to get access to the owning list, but it
leverages the API already used in the IR hierarchy (see, e.g.,
`Instruction::getSublistAccess()`).
If anyone feels like ripping out the calls to `getNextNode()` and
`getPrevNode()` and replacing with direct iterator logic, they can also
remove the access function, etc., but as an incremental step, I'm
maintaining the API where it's currently used in tree.
If these requirements are *not* met, call sites with access to the ilist
can call `iplist<NodeTy>::getNextNode(NodeTy*)` directly, as in
ilistTest.cpp.
Why rewrite this?
The old code was broken, calling `getNext()` on a sentinel that possibly
didn't have a "next" pointer at all! The new code avoids that
particular flavour of UB (see the commit message for r252538 for more
details about the "lucky" memory layout that made this function so
interesting).
There's still some UB here: the end iterator gets downcast to `NodeTy*`,
even when it's a sentinel (which is typically
`ilist_half_node<NodeTy*>`). I'll tackle that in follow-up commits.
See this llvm-dev thread for more details:
http://lists.llvm.org/pipermail/llvm-dev/2015-October/091115.html
What's the danger?
There might be some code that relies on `getNextNode()` or
`getPrevNode()` *never* returning `nullptr` -- i.e., that relies on them
being broken when the sentinel is an `ilist_half_node<NodeTy>`. I tried
to root out those cases with the audits I did leading up to r252380, but
it's possible I missed one or two. I hope not.
(If (1) you have out-of-tree code, (2) you've reverted r252380
temporarily, and (3) you get some weird crashes with this commit, then I
recommend un-reverting r252380 and auditing the compile errors looking
for "strange" implicit conversions.)
llvm-svn: 252694
Create `SymbolTableList`, a wrapper around `iplist` for lists that
automatically manage a symbol table. This commit reduces a ton of code
duplication between the six traits classes that were used previously.
As a drive by, reduce the number of template parameters from 2 to 1 by
using a SymbolTableListParentType metafunction (I originally had this as
a separate commit, but it touched most of the same lines so I squashed
them).
I'm in the process of trying to remove the UB in `createSentinel()` (see
the FIXMEs I added for `ilist_embedded_sentinel_traits` and
`ilist_half_embedded_sentinel_traits`). My eventual goal is to separate
the list logic into a base class layer that knows nothing about (and
isn't templated on) the downcasted nodes -- removing the need to invoke
UB -- but for now I'm just trying to get a handle on all the current use
cases (and cleaning things up as I see them).
Besides these six SymbolTable lists, there are two others that use the
addNode/removeNode/transferNodes() hooks: the `MachineInstruction` and
`MachineBasicBlock` lists. Ideally there'll be a way to factor these
hooks out of the low-level API entirely, but I'm not quite there yet.
llvm-svn: 249602
Summary:
Add a `cleanupendpad` instruction, used to mark exceptional exits out of
cleanups (for languages/targets that can abort a cleanup with another
exception). The `cleanupendpad` instruction is similar to the `catchendpad`
instruction in that it is an EH pad which is the target of unwind edges in
the handler and which itself has an unwind edge to the next EH action.
The `cleanupendpad` instruction, similar to `cleanupret` has a `cleanuppad`
argument indicating which cleanup it exits. The unwind successors of a
`cleanuppad`'s `cleanupendpad`s must agree with each other and with its
`cleanupret`s.
Update WinEHPrepare (and docs/tests) to accomodate `cleanupendpad`.
Reviewers: rnk, andrew.w.kaylor, majnemer
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D12433
llvm-svn: 246751
and make it always preserve debug locations, since all callers wanted this
behavior anyway.
This is addressing a post-commit review feedback for r245589.
NFC (inside the LLVM tree).
llvm-svn: 245622
This introduces new instructions neccessary to implement MSVC-compatible
exception handling support. Most of the middle-end and none of the
back-end haven't been audited or updated to take them into account.
Differential Revision: http://reviews.llvm.org/D11097
llvm-svn: 243766
Summary:
This introduces new instructions neccessary to implement MSVC-compatible
exception handling support. Most of the middle-end and none of the
back-end haven't been audited or updated to take them into account.
Reviewers: rnk, JosephTremoulet, reames, nlewycky, rjmccall
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11041
llvm-svn: 241888
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
While working on another change, I noticed that the naming in this function was mildly deceptive. While fixing that, I took the oppurtunity to modernize some of the code. NFC intended.
llvm-svn: 238252
The patch is generated using clang-tidy misc-use-override check.
This command was used:
tools/clang/tools/extra/clang-tidy/tool/run-clang-tidy.py \
-checks='-*,misc-use-override' -header-filter='llvm|clang' \
-j=32 -fix -format
http://reviews.llvm.org/D8925
llvm-svn: 234679
Update lib/IR and lib/Bitcode to use the new `DebugLoc` API. Added an
explicit conversion to `bool` (avoiding a conversion to `MDLocation`),
since a couple of these use cases need to handle broken code.
llvm-svn: 233585
Summary:
This does not conceptually belongs here. Instead provide a shortcut
getModule() that provides access to the DataLayout.
Reviewers: chandlerc, echristo
Reviewed By: echristo
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D8027
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 231147
Instead, we're going to separate metadata from the Value hierarchy. See
PR21532.
This reverts commit r221375.
This reverts commit r221373.
This reverts commit r221359.
This reverts commit r221167.
This reverts commit r221027.
This reverts commit r221024.
This reverts commit r221023.
This reverts commit r220995.
This reverts commit r220994.
llvm-svn: 221711
Change `Instruction::getAllMetadata()` to modify a vector of `Value`
instead of `MDNode` and update call sites. This is part of PR21433.
llvm-svn: 221027
Change `Instruction::getMetadata()` to return `Value` as part of
PR21433.
Update most callers to use `Instruction::getMDNode()`, which wraps the
result in a `cast_or_null<MDNode>`.
llvm-svn: 221024
Add `Instruction::getMDNode()` that casts to `MDNode` before changing
`Instruction::getMetadata()` to return `Value`. This avoids adding
`cast_or_null<MDNode>` boiler-plate throughout the code.
Part of PR21433.
llvm-svn: 221023
Summary:
Split shouldExpandAtomicInIR() into different versions for Stores/Loads/RMWs/CmpXchgs.
Makes runOnFunction cleaner (no more redundant checking/casting), and will help moving
the X86 backend to this pass.
This requires a way of easily detecting which instructions are atomic.
I followed the pattern of mayReadFromMemory, mayWriteOrReadMemory, etc.. in making
isAtomic() a method of Instruction implemented by a switch on the opcodes.
Test Plan: make check
Reviewers: jfb
Subscribers: mcrosier, llvm-commits
Differential Revision: http://reviews.llvm.org/D5035
llvm-svn: 217080
"Setting" does not equal "copying". This bug has sat dormant for 2 reasons:
1. The unit test was not adequate.
2. Every current user of the "copyFastMathFlags" API is operating on a new instruction.
(ie, all existing fast-math flags are off). If you copy flags to an existing
instruction that has some flags on already, you will not necessarily turn them off
as expected.
I uncovered this bug while trying to implement a fix for PR20802.
llvm-svn: 216939
In order to enable the preservation of noalias function parameter information
after inlining, and the representation of block-level __restrict__ pointer
information (etc.), additional kinds of aliasing metadata will be introduced.
This metadata needs to be carried around in AliasAnalysis::Location objects
(and MMOs at the SDAG level), and so we need to generalize the current scheme
(which is hard-coded to just one TBAA MDNode*).
This commit introduces only the necessary refactoring to allow for the
introduction of other aliasing metadata types, but does not actually introduce
any (that will come in a follow-up commit). What it does introduce is a new
AAMDNodes structure to hold all of the aliasing metadata nodes associated with
a particular memory-accessing instruction, and uses that structure instead of
the raw MDNode* in AliasAnalysis::Location, etc.
No functionality change intended.
llvm-svn: 213859
This requires a number of steps.
1) Move value_use_iterator into the Value class as an implementation
detail
2) Change it to actually be a *Use* iterator rather than a *User*
iterator.
3) Add an adaptor which is a User iterator that always looks through the
Use to the User.
4) Wrap these in Value::use_iterator and Value::user_iterator typedefs.
5) Add the range adaptors as Value::uses() and Value::users().
6) Update *all* of the callers to correctly distinguish between whether
they wanted a use_iterator (and to explicitly dig out the User when
needed), or a user_iterator which makes the Use itself totally
opaque.
Because #6 requires churning essentially everything that walked the
Use-Def chains, I went ahead and added all of the range adaptors and
switched them to range-based loops where appropriate. Also because the
renaming requires at least churning every line of code, it didn't make
any sense to split these up into multiple commits -- all of which would
touch all of the same lies of code.
The result is still not quite optimal. The Value::use_iterator is a nice
regular iterator, but Value::user_iterator is an iterator over User*s
rather than over the User objects themselves. As a consequence, it fits
a bit awkwardly into the range-based world and it has the weird
extra-dereferencing 'operator->' that so many of our iterators have.
I think this could be fixed by providing something which transforms
a range of T&s into a range of T*s, but that *can* be separated into
another patch, and it isn't yet 100% clear whether this is the right
move.
However, this change gets us most of the benefit and cleans up
a substantial amount of code around Use and User. =]
llvm-svn: 203364
already lived there and it is where it belongs -- this is the in-memory
debug location representation.
This is just cleanup -- Modules can actually cope with this, but that
doesn't make it right. After chatting with folks that have out-of-tree
stuff, going ahead and moving the rest of the headers seems preferable.
llvm-svn: 202960
Eventually DataLayoutPass should go away, but for now that is the only easy
way to get a DataLayout in some APIs. This patch only changes the ones that
have easy access to a Module.
One interesting issue with sometimes using DataLayoutPass and sometimes
fetching it from the Module is that we have to make sure they are equivalent.
We can get most of the way there by always constructing the pass with a Module.
In fact, the pass could be changed to point to an external DataLayout instead
of owning one to make this stricter.
Unfortunately, the C api passes a DataLayout, so it has to be up to the caller
to make sure the pass and the module are in sync.
llvm-svn: 202204
When simplifycfg moves an instruction, it must drop metadata it doesn't know
is still valid with the preconditions changes. In particular, it must drop
the range and tbaa metadata.
The patch implements this with an utility function to drop all metadata not
in a white list.
llvm-svn: 200322
into their new header subdirectory: include/llvm/IR. This matches the
directory structure of lib, and begins to correct a long standing point
of file layout clutter in LLVM.
There are still more header files to move here, but I wanted to handle
them in separate commits to make tracking what files make sense at each
layer easier.
The only really questionable files here are the target intrinsic
tablegen files. But that's a battle I'd rather not fight today.
I've updated both CMake and Makefile build systems (I think, and my
tests think, but I may have missed something).
I've also re-sorted the includes throughout the project. I'll be
committing updates to Clang, DragonEgg, and Polly momentarily.
llvm-svn: 171366