Take DW_FORM_implicit_const attribute value into account when profiling
DIEAbbrevData.
Currently if we have two similar types with implicit_const attributes and
different values we end up with only one abbrev in .debug_abbrev section.
For example consider two structures: S1 with implicit_const attribute ATTR
and value VAL1 and S2 with implicit_const ATTR and value VAL2.
The .debug_abbrev section will contain only 1 related record:
[N] DW_TAG_structure_type DW_CHILDREN_yes
DW_AT_ATTR DW_FORM_implicit_const VAL1
// ....
This is incorrect as struct S2 (with VAL2) will use abbrev record with VAL1.
With this patch we will have two different abbreviations here:
[N] DW_TAG_structure_type DW_CHILDREN_yes
DW_AT_ATTR DW_FORM_implicit_const VAL1
// ....
[M] DW_TAG_structure_type DW_CHILDREN_yes
DW_AT_ATTR DW_FORM_implicit_const VAL2
// ....
llvm-svn: 296691
This patch changes the CMake configuration so that it always
generates the test/lit.site.cfg file, even when testing is disabled.
This allows users to test libc++ without requiring them to have
a full LLVM checkout on their machine.
llvm-svn: 296685
- We only need the information from the base class, not the additional
details in the LiveInterval class.
- Spread more `const`
- Some code cleanup
llvm-svn: 296684
Summary:
Avoids tons of prologue boilerplate when arguments are passed in memory
and left in memory. This can happen in a debug build or in a release
build when an argument alloca is escaped. This will dramatically affect
the code size of x86 debug builds, because X86 fast isel doesn't handle
arguments passed in memory at all. It only handles the x86_64 case of up
to 6 basic register parameters.
This is implemented by analyzing the entry block before ISel to identify
copy elision candidates. A copy elision candidate is an argument that is
used to fully initialize an alloca before any other possibly escaping
uses of that alloca. If an argument is a copy elision candidate, we set
a flag on the InputArg. If the the target generates loads from a fixed
stack object that matches the size and alignment requirements of the
alloca, the SelectionDAG builder will delete the stack object created
for the alloca and replace it with the fixed stack object. The load is
left behind to satisfy any remaining uses of the argument value. The
store is now dead and is therefore elided. The fixed stack object is
also marked as mutable, as it may now be modified by the user, and it
would be invalid to rematerialize the initial load from it.
Supersedes D28388
Fixes PR26328
Reviewers: chandlerc, MatzeB, qcolombet, inglorion, hans
Subscribers: igorb, llvm-commits
Differential Revision: https://reviews.llvm.org/D29668
llvm-svn: 296683
I am planning to use this tool to find too noisy (missed) optimization
remarks. Long term it may actually be better to just have another tool that
exports the remarks into an sqlite database and perform queries like this in
SQL.
This splits out the YAML parsing from opt-viewer.py into a new Python module
optrecord.py.
This is the result of the script on the LLVM testsuite:
Total number of remarks 714433
Top 10 remarks by pass:
inline 52%
gvn 24%
licm 13%
loop-vectorize 5%
asm-printer 3%
loop-unroll 1%
regalloc 1%
inline-cost 0%
slp-vectorizer 0%
loop-delete 0%
Top 10 remarks:
gvn/LoadClobbered 20%
inline/Inlined 19%
inline/CanBeInlined 18%
inline/NoDefinition 9%
licm/LoadWithLoopInvariantAddressInvalidated 6%
licm/Hoisted 6%
asm-printer/InstructionCount 3%
inline/TooCostly 3%
gvn/LoadElim 3%
loop-vectorize/MissedDetails 2%
Beside some refactoring, I also changed optrecords not to use context to
access global data (max_hotness). Because of the separate module this would
have required splitting context into two. However it's not possible to access
the optrecord context from the SourceFileRenderer when calling back to
Remark.RelativeHotness.
llvm-svn: 296682
Multi-disjunct access maps can easily result in inbound assumptions which
explode in case of many memory accesses and many parameters. This change reduces
compilation time of some larger kernel from over 15 minutes to less than 16
seconds.
Interesting is the test case test/ScopInfo/multidim_param_in_subscript.ll
which has a memory access
[n] -> { Stmt_for_body3[i0, i1] -> MemRef_A[i0, -1 + n - i1] }
which requires folding, but where only a single disjunct remains. We can still
model this test case even when only using limited memory folding.
For people only reading commit messages, here the comment that explains what
memory folding is:
To recover memory accesses with array size parameters in the subscript
expression we post-process the delinearization results.
We would normally recover from an access A[exp0(i) * N + exp1(i)] into an
array A[][N] the 2D access A[exp0(i)][exp1(i)]. However, another valid
delinearization is A[exp0(i) - 1][exp1(i) + N] which - depending on the
range of exp1(i) - may be preferrable. Specifically, for cases where we
know exp1(i) is negative, we want to choose the latter expression.
As we commonly do not have any information about the range of exp1(i),
we do not choose one of the two options, but instead create a piecewise
access function that adds the (-1, N) offsets as soon as exp1(i) becomes
negative. For a 2D array such an access function is created by applying
the piecewise map:
[i,j] -> [i, j] : j >= 0
[i,j] -> [i-1, j+N] : j < 0
After this patch we generate only the first case, except for situations where
we can proove the first case to be invalid and can consequently select the
second without introducing disjuncts.
llvm-svn: 296679
Looks like .gdb.index and its support classes do things that they don't
have to or shouldn't do do. This patch addresses one of these issues.
GdbHashTab class is a hash table class. Just like other in-memory hash
tables, that incrementally updates its internal data and resizes buckets
as new elements are added so that key lookup is always fast.
But that is completely not necessary.
Unlike debuggers, we only produce hash tables for .gdb.index and
never read them. So incrementally updating a hash table in memory is
just a waste of resource and complicates the code. What we should
do is to accumulate symbols and then create the final hash table
at once.
llvm-svn: 296678
Summary:
This patch moves the clearUnusedBits calls into the two different initialization paths for APInt from a uint64_t. This allows the compiler to better optimize the clearing of the unused bits for the single word case. And it puts the clearing for the multi word case into the initSlowCase function to save code. In the common case of initializing with 0 this allows the clearing to be completely optimized out for the single word case.
On my local x86 build this is showing a ~45kb reduction in the size of the opt binary.
Reviewers: RKSimon, hans, majnemer, davide, MatzeB
Reviewed By: hans
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D30486
llvm-svn: 296677
This patch adds a MachineSSA pass that coalesces blocks that branch
on the same condition.
Committing on behalf of Lei Huang.
Differential Revision: https://reviews.llvm.org/D28249
llvm-svn: 296670
Add check that deleted nodes do not get added to worklist. This can
occur when a node's operand is simplified to an existing node.
This fixes PR32108.
Reviewers: jyknight, hfinkel, chandlerc
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D30506
llvm-svn: 296668
This was due to the test stream choosing an arbitrary partition
index for introducing the discontinuity rather than choosing
an index that would be correctly aligned for the type of data.
Also added an assertion into FixedStreamArray so that this will
be caught on all bots in the future, and not just the UBSan bot.
llvm-svn: 296661
Many things were wrong:
- We didn't always allow wrapping after "as", which can be necessary.
- We used to Undestand the identifier after "as" as a start of a name.
- We didn't properly parse the structure of the expression with "as"
having the precedence of relational operators
llvm-svn: 296659
Summary: With clang-cl gaining support for link-time optimization, we can now enable builds using LTO when using clang-cl and lld on Windows. To do this, we must not pass the -flto flag to the linker; lld-link does not understand it, but will perform LTO automatically when it encounters bitcode files. We also don't pass /Brepro when using LTO - the compiler doesn't generate object files for LTO, so passing the flag would only result in a warning about it being unused.
Reviewers: rnk, ruiu, hans
Reviewed By: hans
Subscribers: mgorny, mehdi_amini, llvm-commits
Differential Revision: https://reviews.llvm.org/D30240
llvm-svn: 296658
This is a stopgap fix for PR31863, a regression introduced in r276159.
Consider this snippet:
struct FVector;
struct FVector {};
struct FBox {
FVector Min;
FBox(int);
};
namespace {
FBox InvalidBoundingBox(0);
}
While parsing the DECL_VAR for 'struct FBox', clang recursively read all the
dep decls until it finds the DECL_CXX_RECORD forward declaration for 'struct
FVector'. Then, it resumes all the way up back to DECL_VAR handling in
`ReadDeclRecord`, where it checks if `isConsumerInterestedIn` for the decl.
One of the condition for `isConsumerInterestedIn` to return false is if the
VarDecl is imported from a module `D->getImportedOwningModule()`, because it
will get emitted when we import the relevant module. However, before checking
if it comes from a module, clang checks if `Ctx.DeclMustBeEmitted(D)`, which
triggers the emission of 'struct FBox'. Since one of its fields is still
incomplete, it crashes.
Instead, check if `D->getImportedOwningModule()` is true before calling
`Ctx.DeclMustBeEmitted(D)`.
Differential Revision: https://reviews.llvm.org/D29753
rdar://problem/30173654
llvm-svn: 296656
Summary: Points the user to look at function pointer assignments.
Reviewers: kcc, eugenis, kubamracek
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D30432
llvm-svn: 296653
DWARF may define a default lower-bound for arrays in languages defined
in a particular DWARF version. But the logic to suppress an
unnecessary lower-bound attribute was looking at the hard-coded
default DWARF version, not the version that had been requested.
Also updated the list with all languages defined in DWARF v5.
Differential Revision: http://reviews.llvm.org/D30484
llvm-svn: 296652
Resubmit r295336 after the bug with non-zero offset patterns on BE targets is fixed (r296336).
Support {a|s}ext, {a|z|s}ext load nodes as a part of load combine patters.
Reviewed By: filcab
Differential Revision: https://reviews.llvm.org/D29591
llvm-svn: 296651
and the nature of a declaration
This commit adds an external_source_symbol attribute to Clang. This attribute
specifies that a declaration originates from an external source and describes
the nature of that source. This attribute will be used to improve IDE features
like 'jump-to-definition' for mixed-language projects or project that use
auto-generated code.
rdar://30423368
Differential Revision: https://reviews.llvm.org/D29819
llvm-svn: 296649
In the following code involving GNU statement-expression extension:
struct S {
~S();
};
void foo() {
const S &x = ({ return; S(); });
}
function 'foo()' returns before reference x is initialized. We shouldn't call
the destructor for the temporary object lifetime-extended by 'x' in this case,
because the object never gets constructed in the first place.
The real problem is probably in the CFG somewhere, so this is a quick-and-dirty
hotfix rather than the perfect solution.
A patch by Artem Dergachev!
rdar://problem/30759076
Differential Revision: https://reviews.llvm.org/D30499
llvm-svn: 296646
Rui Ueyama