Summary:
There are a number of passes that could be sped up by using dominator tree DFS numbers to order or compare things across multiple bbs
(MemorySSA, MergedLoadStoreMotion, EarlyCSE, Sinking, GVN, NewGVN, for starters :P).
For example, GVN/CSE elimination can be done with a simple stack/etc (instead of full-on scoped hash table or repeated leader set walks)
if the DFS pair is stored next to leaders.
The dominator tree keeps them, and the DOM tree nodes expose them as public, but you have no guarantee they are up to date (and in fact,
if you split blocks or whatever during your pass, they definitely won't be)
This means passes either have to compute their own versions[1], or make 32 queries, or ....
Rather than try to hide this, i just made the API public, and make it do nothing if the numbers are already valid.
[1] Which we want as a non-recursive walk, which is not pretty, sadly,
because it cannot use the depth first iterators since you don't get called on the way back up. So you either have to do one walk with po_iterator
and one with df_iterator, or write your own non-recursive walk that looks identical to the one in updateDFSNumbers.
Reviewers: chandlerc
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D8946
llvm-svn: 234930
As a follow-up to r234850, add an implicit conversion from
`DISubprogram` to `DIScope` to support Kaleidoscope Ch. 8. This also
reverts that band-aid from r234890.
(/me learns *again* to build Kaleidoscope before commit...)
llvm-svn: 234904
Some targets (ie. Mips) have additional rules for ordering the relocation
table entries. Allow them to override generic sortRelocs(), which sorts
entries by Offset.
Then override this function for Mips, to emit HI16 and GOT16 relocations
against the local symbol in pair with the corresponding LO16 relocation.
Patch by Vladimir Stefanovic.
Differential Revision: http://reviews.llvm.org/D7414
llvm-svn: 234883
Summary:
This transformation reassociates a n-ary add so that the add can partially reuse
existing instructions. For example, this pass can simplify
void foo(int a, int b) {
bar(a + b);
bar((a + 2) + b);
}
to
void foo(int a, int b) {
int t = a + b;
bar(t);
bar(t + 2);
}
saving one add instruction.
Fixes PR22357 (https://llvm.org/bugs/show_bug.cgi?id=22357).
Test Plan: nary-add.ll
Reviewers: broune, dberlin, hfinkel, meheff, sanjoy, atrick
Reviewed By: sanjoy, atrick
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D8950
llvm-svn: 234855
Change `DICompileUnit::replaceSubprograms()` and
`DICompileUnit::replaceGlobalVariables()` to match the `MDCompileUnit`
equivalents that they're wrapping.
llvm-svn: 234852
When a loadable (.so or .dylib) pass is built with assertions enabled and
loaded into the 'opt' tool, we need to ensure that the extra symbols that such
passes depend on are linked into the tool.
llvm-svn: 234851
Gut the `DIDescriptor` wrappers around `MDLocalScope` subclasses. Note
that `DILexicalBlock` wraps `MDLexicalBlockBase`, not `MDLexicalBlock`.
llvm-svn: 234850
Bring function documentation for ScalarEvolutionExpander up to code by
not repeating the function name in the comment documenting
functionality. Reflow the edited comments where needed.
llvm-svn: 234847
Summary:
Runtime unrolling of loops needs to emit an expression to compute the
loop's runtime trip-count. Avoid runtime unrolling if this computation
will be expensive.
Depends on D8993.
Reviewers: atrick
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D8994
llvm-svn: 234846
Summary:
Move isHighCostExpansion from IndVarSimplify to SCEVExpander. This
exposed function will be used in a subsequent change.
Reviewers: bogner, atrick
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D8995
llvm-svn: 234844
Add a few functions from `DILexicalBlock` to `MDLexicalBlockBase`,
leaving `DILexicalBlock` a simple wrapper.
IMO, the new functions (`getLine()` and `getColumn()`) don't really
belong in the base class, but to simplify transitioning old code it
seems like the right incremental step. I've explicitly deleted them in
`MDLexicalBlockFile`, and eventually the callers should be updated to
downcast to `MDLexicalBlock` directly and the forwarding functions
removed.
llvm-svn: 234842
Gut all the non-pointer API from the variable wrappers, except an
implicit conversion from `DIGlobalVariable` to `DIDescriptor`. Note
that if you're updating out-of-tree code, `DIVariable` wraps
`MDLocalVariable` (`MDVariable` is a common base class shared with
`MDGlobalVariable`).
llvm-svn: 234840
This is along the same lines as r234832, but for `DILocation`. Clean
out all accessors from `DILocation`. Any callers should be using
`MDLocation` directly (e.g., via `operator->()`).
llvm-svn: 234835
Completely gut `DIExpression`, turning it into a simple wrapper around
`MDExpression *`. There are two bits of magic left:
- It's constructed from `const MDExpression*` but convertible to
`MDExpression*`.
- It's default-constructed to `nullptr`.
Otherwise, it should behave quite like a raw pointer. Once I've done
the same to the rest of the `DIDescriptor` subclasses, I'll come back to
delete them entirely (and update call sites as necessary to deal with
the missing magic).
llvm-svn: 234832
As documented in PR23200 (and the FIXMEs I've added to the code here),
this logic is fairly broken: it modifies the `LLVMContext` in a way that
affects other modules and cannot be serialized to assembly/bitcode. For
now, move it over to `MDLocation::computeNewDiscriminators()` anyway.
llvm-svn: 234825
I don't see a reason to add the `copyWithNewScope()` API over to
`MDLocation` -- it seems to be a holdover from when creating locations
required knowing details of operand layout -- so change
`AddDiscriminators` to call `MDLocation::get()` directly. Should be no
functionality change here.
llvm-svn: 234824
There's only one user of the various `DIObjCProperty::is*Property()`
accessors -- `DwarfUnit::constructTypeDIE()` -- and it's just using the
reverse logic to reconstruct the bitfield. Drop this API and simplify
the only caller.
llvm-svn: 234818
These accessors in `DIDerivedType` should only be called when `DbgNode`
really is a `MDDerivedType`, not just a `MDDerivedTypeBase`. Assume
that it is.
llvm-svn: 234812
This is almost NFC, but I'm removing some assertions against `nullptr`.
The assertions aren't worth all that much since we'll typically get
segfaults at the same site (and I imagine ASan catches this sort of
thing), and besides: the whole idea is to replace the `DIDescriptor`
hierarchy with raw pointers to the new one.
llvm-svn: 234802
Instead of calling the somewhat confusingly-named
`DIVariable::isInlinedFnArgument()`, do the check directly here.
There's possibly a small functionality change here: instead of
`dyn_cast<>`'ing `DV->getScope()` to `MDSubprogram`, I'm looking up the
scope chain for the actual subprogram. I suspect that this is a no-op
for function arguments so in practise there isn't a real difference.
I've also added a `FIXME` to check the `inlinedAt:` chain instead, since
I wonder if that would be more reliable than the
`MDSubprogram::describes()` function.
Since this was the only user of `DIVariable::isInlinedFnArgument()`,
delete it.
llvm-svn: 234799
`DIGlobalVariable::getGlobal()` isn't really helpful, it just does a
`dyn_cast_or_null<>`. Simplify its only user by doing the cast directly
and delete the code.
llvm-svn: 234796
I don't really like this function at all -- I think it should be as
simple as `return getFunction() == F` -- but for now this seems like the
best we can do.
llvm-svn: 234778
This reverts commit r234717, reapplying r234698 (in spirit).
As described in r234717, the original `Verifier` check had a
use-after-free. Instead of storing pointers to "interesting" debug info
intrinsics whose bit piece expressions should be verified once we have
typerefs, do a second traversal. I've added a testcase to catch the
`llc` crasher.
Original commit message:
Verifier: Check for incompatible bit piece expressions
Convert an assertion into a `Verifier` check. Bit piece expressions
must fit inside the variable, and mustn't be the entire variable.
Catching this in the verifier will help us find bugs sooner, and makes
`DIVariable::getSizeInBits()` dead code.
llvm-svn: 234776
This reverts commit r234698.
This caused a use-after-free: `QueuedBitPieceExpressions` holds onto
references to `DbgInfoIntrinsic`s and references them past where they're
deleted (this is because the verifier is run as a function pass, and
then `verifyTypeRefs()` is called during `doFinalization()`).
I'll include a reduced crasher for `llc` when I recommit the check.
llvm-svn: 234717
Summary:
When instruction bundling is enabled and the -mc-relax-all flag is
set, we can write bundle padding directly into fragments and avoid
creating large number of fragments significantly reducing LLVM MC
memory usage.
Test Plan: Regression test attached
Reviewers: eliben
Subscribers: jfb, mseaborn
Differential Revision: http://reviews.llvm.org/D8072
llvm-svn: 234714
Change `MDSubprogram::getFunction()` and
`MDGlobalVariable::getConstant()` to return a `Constant`. Previously,
both returned `ConstantAsMetadata`.
llvm-svn: 234699
Convert an assertion into a `Verifier` check. Bit piece expressions
must fit inside the variable, and mustn't be the entire variable.
Catching this in the verifier will help us find bugs sooner, and makes
`DIVariable::getSizeInBits()` dead code.
llvm-svn: 234698
r234696 replaced the only use of `DIDescriptor::replaceAllUsesWith()`
with `DIBuilder::replaceTemporary()` (added in r234695). Delete the
dead code.
llvm-svn: 234697
Add `DIBuilder::replaceTemporary()` as a replacement for
`DIDescriptor::replaceAllUsesWith()`. I'll update clang to use the new
method, and then come back to delete the original.
This method dispatches to `replaceAllUsesWith()` or
`replaceWithUniqued()`, depending on whether the replacement is actually
a different node from the original.
llvm-svn: 234695
