This is similar to the 'tail' marker, except that it guarantees that
tail call optimization will occur. It also comes with convervative IR
verification rules that ensure that tail call optimization is possible.
Reviewers: nicholas
Differential Revision: http://llvm-reviews.chandlerc.com/D3240
llvm-svn: 207143
Implement DebugInfoVerifier, which steals verification relying on
DebugInfoFinder from Verifier.
- Adds LegacyDebugInfoVerifierPassPass, a ModulePass which wraps
DebugInfoVerifier. Uses -verify-di command-line flag.
- Change verifyModule() to invoke DebugInfoVerifier as well as
Verifier.
- Add a call to createDebugInfoVerifierPass() wherever there was a
call to createVerifierPass().
This implementation as a module pass should sidestep efficiency issues,
allowing us to turn debug info verification back on.
<rdar://problem/15500563>
llvm-svn: 206300
This is like the LLVMMatchType, except the verifier checks that the
second argument is a vector with the same base type and half the
number of elements.
This will be used by the ARM64 backend.
llvm-svn: 205079
These are used in the ARM backends to aid type-checking on patterns involving
intrinsics. By making sure one argument is an extended/truncated version of
another.
However, there's no reason to limit them to just vectors types. For example
AArch64 has the instruction "uqshrn sD, dN, #imm" which would naturally use an
intrinsic taking an i64 and returning an i32.
llvm-svn: 205003
This adds back r204781.
Original message:
Aliases are just another name for a position in a file. As such, the
regular symbol resolutions are not applied. For example, given
define void @my_func() {
ret void
}
@my_alias = alias weak void ()* @my_func
@my_alias2 = alias void ()* @my_alias
We produce without this patch:
.weak my_alias
my_alias = my_func
.globl my_alias2
my_alias2 = my_alias
That is, in the resulting ELF file my_alias, my_func and my_alias are
just 3 names pointing to offset 0 of .text. That is *not* the
semantics of IR linking. For example, linking in a
@my_alias = alias void ()* @other_func
would require the strong my_alias to override the weak one and
my_alias2 would end up pointing to other_func.
There is no way to represent that with aliases being just another
name, so the best solution seems to be to just disallow it, converting
a miscompile into an error.
llvm-svn: 204934
This reverts commit r204781.
I will follow up to with msan folks to see what is what they
were trying to do with aliases to weak aliases.
llvm-svn: 204784
Aliases are just another name for a position in a file. As such, the
regular symbol resolutions are not applied. For example, given
define void @my_func() {
ret void
}
@my_alias = alias weak void ()* @my_func
@my_alias2 = alias void ()* @my_alias
We produce without this patch:
.weak my_alias
my_alias = my_func
.globl my_alias2
my_alias2 = my_alias
That is, in the resulting ELF file my_alias, my_func and my_alias are
just 3 names pointing to offset 0 of .text. That is *not* the
semantics of IR linking. For example, linking in a
@my_alias = alias void ()* @other_func
would require the strong my_alias to override the weak one and
my_alias2 would end up pointing to other_func.
There is no way to represent that with aliases being just another
name, so the best solution seems to be to just disallow it, converting
a miscompile into an error.
llvm-svn: 204781
On ELF and COFF an alias is just another name for a position in the file.
There is no way to refer to a position in another file, so an alias to
undefined is meaningless.
MachO currently doesn't support aliases. The spec has a N_INDR, which when
implemented will have a different set of restrictions. Adding support for
it shouldn't be harder than any other IR extension.
For now, having the IR represent what is actually possible with current
tools makes it easier to fix the design of GlobalAlias.
llvm-svn: 203705
The syntax for "cmpxchg" should now look something like:
cmpxchg i32* %addr, i32 42, i32 3 acquire monotonic
where the second ordering argument gives the required semantics in the case
that no exchange takes place. It should be no stronger than the first ordering
constraint and cannot be either "release" or "acq_rel" (since no store will
have taken place).
rdar://problem/15996804
llvm-svn: 203559
Extend the error message generated by the Verifier when an intrinsic
name does not match the expected mangling to include the expected
name. Simplifies debugging.
Patch by Philip Reames!
llvm-svn: 203490
MSVC (2012, 2013, 2013 Nov CTP) fail on the following code:
int main() {
int arr[] = {1, 2};
for (int i : arr)
do {} while (0);
}
The fix is to put {} around the for loop. I've reported this to the MSVC
team.
llvm-svn: 203371
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
a bit surprising, as the class is almost entirely abstracted away from
any particular IR, however it encodes the comparsion predicates which
mutate ranges as ICmp predicate codes. This is reasonable as they're
used for both instructions and constants. Thus, it belongs in the IR
library with instructions and constants.
llvm-svn: 202838
various opt verifier commandline options.
Mostly mechanical wiring of the verifier to the new pass manager.
Exercises one of the more unusual aspects of it -- a pass can be either
a module or function pass interchangably. If this is ever problematic,
we can make things more constrained, but for things like the verifier
where there is an "obvious" applicability at both levels, it seems
convenient.
This is the next-to-last piece of basic functionality left to make the
opt commandline driving of the new pass manager minimally functional for
testing and further development. There is still a lot to be done there
(notably the factoring into .def files to kill the current boilerplate
code) but it is relatively uninteresting. The only interesting bit left
for minimal functionality is supporting the registration of analyses.
I'm planning on doing that on top of the .def file switch mostly because
the boilerplate for the analyses would be significantly worse.
llvm-svn: 199646
This makes the 'verifyFunction' and 'verifyModule' functions totally
independent operations on the LLVM IR. It also cleans up their API a bit
by lifting the abort behavior into their clients and just using an
optional raw_ostream parameter to control printing.
The implementation of the verifier is now just an InstVisitor with no
multiple inheritance. It also is significantly more const-correct, and
hides the const violations internally. The two layers that force us to
break const correctness are building a DomTree and dispatching through
the InstVisitor.
A new VerifierPass is used to implement the legacy pass manager
interface in terms of the other pieces.
The error messages produced may be slightly different now, and we may
have slightly different short circuiting behavior with different usage
models of the verifier, but generally everything works equivalently and
this unblocks wiring the verifier up to the new pass manager.
llvm-svn: 199569
and tweak comments prior to more invasive surgery. Also clean up some
other non-doxygen comments, and run clang-format over the parts that are
going to change dramatically in subsequent commits so that those don't
get cluttered with formatting changes.
No functionality changed.
llvm-svn: 199489
the verifier after ensuring the CFG is at least usefully formed.
This fixes a number of problems:
1) The PreVerifier was missing the controls the Verifier provides over
*how* an invalid module is handled -- it just aborted the program!
Now it uses the same logic as the Verifier which is significantly
more library-friendly.
2) The DominatorTree used previously could have been cached and not
updated due to bugs in prior passes and we would silently use the
stale tree. This could cause dominance errors to not be as quickly
diagnosed.
3) We can now (in the next patch) pull the functionality of the verifier
apart from the pass infrastructure so that you can verify IR without
having any form of pass manager. This in turn frees the code to share
logic between old and new pass manager variants.
Along the way I fixed at least one annoying bug -- the state for
'Broken' wasn't being cleared from run to run causing all functions
visited after the first broken function to be marked as broken
regardless of whether *they* were a problem. Fortunately, I don't really
know much of a way to observe this peculiarity.
In case folks are worried about the runtime cost, its negligible.
I looked at running the entire regression test suite (which should be
a relatively good use of the verifier) before and after but was unable
to even measure the time spent on the verifier and there was no
regresion from before to after. I checked both with debug builds and
optimized builds.
llvm-svn: 199487
This makes things a lot easier, because we can now talk about the
"argument allocation", which allocates all the memory for the call in
one shot.
The only functional change is to the verifier for a feature that hasn't
shipped yet.
llvm-svn: 199434
Representing dllexport/dllimport as distinct linkage types prevents using
these attributes on templates and inline functions.
Instead of introducing further mixed linkage types to include linkonce and
weak ODR, the old import/export linkage types are replaced with a new
separate visibility-like specifier:
define available_externally dllimport void @f() {}
@Var = dllexport global i32 1, align 4
Linkage for dllexported globals and functions is now equal to their linkage
without dllexport. Imported globals and functions must be either
declarations with external linkage, or definitions with
AvailableExternallyLinkage.
llvm-svn: 199218
Representing dllexport/dllimport as distinct linkage types prevents using
these attributes on templates and inline functions.
Instead of introducing further mixed linkage types to include linkonce and
weak ODR, the old import/export linkage types are replaced with a new
separate visibility-like specifier:
define available_externally dllimport void @f() {}
@Var = dllexport global i32 1, align 4
Linkage for dllexported globals and functions is now equal to their linkage
without dllexport. Imported globals and functions must be either
declarations with external linkage, or definitions with
AvailableExternallyLinkage.
llvm-svn: 199204
can be used by both the new pass manager and the old.
This removes it from any of the virtual mess of the pass interfaces and
lets it derive cleanly from the DominatorTreeBase<> template. In turn,
tons of boilerplate interface can be nuked and it turns into a very
straightforward extension of the base DominatorTree interface.
The old analysis pass is now a simple wrapper. The names and style of
this split should match the split between CallGraph and
CallGraphWrapperPass. All of the users of DominatorTree have been
updated to match using many of the same tricks as with CallGraph. The
goal is that the common type remains the resulting DominatorTree rather
than the pass. This will make subsequent work toward the new pass
manager significantly easier.
Also in numerous places things became cleaner because I switched from
re-running the pass (!!! mid way through some other passes run!!!) to
directly recomputing the domtree.
llvm-svn: 199104
directory. These passes are already defined in the IR library, and it
doesn't make any sense to have the headers in Analysis.
Long term, I think there is going to be a much better way to divide
these matters. The dominators code should be fully separated into the
abstract graph algorithm and have that put in Support where it becomes
obvious that evn Clang's CFGBlock's can use it. Then the verifier can
manually construct dominance information from the Support-driven
interface while the Analysis library can provide a pass which both
caches, reconstructs, and supports a nice update API.
But those are very long term, and so I don't want to leave the really
confusing structure until that day arrives.
llvm-svn: 199082
operand into the Value interface just like the core print method is.
That gives a more conistent organization to the IR printing interfaces
-- they are all attached to the IR objects themselves. Also, update all
the users.
This removes the 'Writer.h' header which contained only a single function
declaration.
llvm-svn: 198836
are part of the core IR library in order to support dumping and other
basic functionality.
Rename the 'Assembly' include directory to 'AsmParser' to match the
library name and the only functionality left their -- printing has been
in the core IR library for quite some time.
Update all of the #includes to match.
All of this started because I wanted to have the layering in good shape
before I started adding support for printing LLVM IR using the new pass
infrastructure, and commandline support for the new pass infrastructure.
llvm-svn: 198688
The inalloca attribute is designed to support passing C++ objects by
value in the Microsoft C++ ABI. It behaves the same as byval, except
that it always implies that the argument is in memory and that the bytes
are never copied. This attribute allows the caller to take the address
of an outgoing argument's memory and execute arbitrary code to store
into it.
This patch adds basic IR support, docs, and verification. It does not
attempt to implement any lowering or fix any possibly broken transforms.
When this patch lands, a complete description of this feature should
appear at http://llvm.org/docs/InAlloca.html .
Differential Revision: http://llvm-reviews.chandlerc.com/D2173
llvm-svn: 197645
The sefault occurs due to an infinite loop when the verifier tries to
determine the size of a type of the form "%rt = type { %rt }" while
checking an alloca of the type.
llvm-svn: 196626
(except functions marked always_inline).
Functions with 'optnone' must also have 'noinline' so they don't get
inlined into any other function.
Based on work by Andrea Di Biagio.
llvm-svn: 195046
Debug info verifier is part of the verifier which is a Function Pass.
Tot currently tries to pull all reachable debug info MDNodes in each function,
which is too time-consuming. The correct fix seems to be separating debug info
verification to its own module pass.
I will disable the debug info verifier until a correct fix is found.
For Bill's testing case, enabling debug info verifier increase compile
time from 11s to 11m.
llvm-svn: 194986
We used to collect debug info MDNodes in doInitialization and verify them in
doFinalization. That is incorrect since MDNodes can be modified by passes run
between doInitialization and doFinalization.
To fix the problem, we handle debug info MDNodes that can be reached from a
function in runOnFunction (i.e we collect those nodes by calling processDeclare,
processValue and processLocation, and then verify them in runOnFunction).
We handle debug info MDNodes that can be reached from named metadata in
doFinalization. This is in line with how Verifier handles module-level data
(they are verified in doFinalization).
rdar://15472296
llvm-svn: 194974
We used to depend on running processModule before the other public functions
such as processDeclare, processValue and processLocation. We are now relaxing
the constraint by adding a module argument to the three functions and
letting the three functions to initialize the type map. This will be used in
a follow-on patch that collects nodes reachable from a Function.
llvm-svn: 194973
verifyFunction needs to call doInitialization to collect metadata and avoid
crashing when verifying debug info in a function.
But it should not call doFinalization since that is where the verifier will
check declarations, variables and aliases, which is not desirable when one
only wants to verify a function.
A possible cleanup would be to split the class into a ModuleVerifier and
FunctionVerifier.
Issue reported by Ilia Filippov. Patch by Michael Kruse.
llvm-svn: 194574
linkonce_odr_auto_hide was in incomplete attempt to implement a way
for the linker to hide symbols that are known to be available in every
TU and whose addresses are not relevant for a particular DSO.
It was redundant in that it all its uses are equivalent to
linkonce_odr+unnamed_addr. Unlike those, it has never been connected
to clang or llvm's optimizers, so it was effectively dead.
Given that nothing produces it, this patch just nukes it
(other than the llvm-c enum value).
llvm-svn: 193865
The function verifyFunction() in lib/IR/Verifier.cpp misses some
calls. It creates a temporary FunctionPassManager that will run a
single Verifier pass. Unfortunately, FunctionPassManager is no
PassManager and does not call doInitialization() and doFinalization()
by itself. Verifier does important tasks in doInitialization() such as
collecting type information used to check DebugInfo metadata and
doFinalization() does some additional checks. Therefore these checks
were missed and debug info couldn't be verified at all, it just
crashed if the function had some.
verifyFunction() is currently not used in llvm unless -debug option is
enabled, and in unittests/IR/VerifierTest.cpp
VerifierTest had to be changed to create the function in a module from
which the type debug info can be collected.
Patch by Michael Kruse.
llvm-svn: 193719
In DIBuilder, the context field of a TAG_member is updated to use the
scope reference. Verifier is updated accordingly.
DebugInfoFinder now needs to generate a type identifier map to have
access to the actual scope. Same applies for BreakpointPrinter.
processModule of DebugInfoFinder is called during initialization phase
of the verifier to make sure the type identifier map is constructed early
enough.
We are now able to unique a simple class as demonstrated by the added
testing case.
llvm-svn: 190334
The work on this project was left in an unfinished and inconsistent state.
Hopefully someone will eventually get a chance to implement this feature, but
in the meantime, it is better to put things back the way the were. I have
left support in the bitcode reader to handle the case-range bitcode format,
so that we do not lose bitcode compatibility with the llvm 3.3 release.
This reverts the following commits: 155464, 156374, 156377, 156613, 156704,
156757, 156804 156808, 156985, 157046, 157112, 157183, 157315, 157384, 157575,
157576, 157586, 157612, 157810, 157814, 157815, 157880, 157881, 157882, 157884,
157887, 157901, 158979, 157987, 157989, 158986, 158997, 159076, 159101, 159100,
159200, 159201, 159207, 159527, 159532, 159540, 159583, 159618, 159658, 159659,
159660, 159661, 159703, 159704, 160076, 167356, 172025, 186736
llvm-svn: 190328
functions marked 'nobuiltin'. That approach doesn't play well with LTO, and
there's no harm in marking a call as 'builtin' if it was going to be a builtin
regardless.
llvm-svn: 190233
This function attribute indicates that the function is not optimized
by any optimization or code generator passes with the
exception of interprocedural optimization passes.
llvm-svn: 189101
Also remove checking of llvm.dbg.sp since it is not used in generating dwarf.
Current state of Finder:
DebugInfoFinder tries to list all debug info MDNodes used in a module. To
list debug info MDNodes used by an instruction, DebugInfoFinder provides
processDeclare, processValue and processLocation to handle DbgDeclareInst,
DbgValueInst and DbgLoc attached to instructions. processModule will go
through all DICompileUnits in llvm.dbg.cu and list debug info MDNodes
used by the CUs.
TODO:
1> Finder has a list of CUs, SPs, Types, Scopes and global variables. We
need to add a list of variables that are used by DbgDeclareInst and
DbgValueInst.
2> MDString fields should be null or isa<MDString> and MDNode fields should be
null or isa<MDNode>. We currently use empty string or int 0 to represent null.
3> Go though Verify functions and make sure that they check field types.
4> Clean up existing testing cases to remove llvm.dbg.sp and make sure each
testing case has a llvm.dbg.cu.
Re-apply r187609 with fix to pass ocaml binding. vmcore.ml generates a debug
location with scope being metadata !{}, in verifier we treat this as a null
scope.
llvm-svn: 187812
Also remove checking of llvm.dbg.sp since it is not used in generating dwarf.
Current state of Finder:
DebugInfoFinder tries to list all debug info MDNodes used in a module. To
list debug info MDNodes used by an instruction, DebugInfoFinder provides
processDeclare, processValue and processLocation to handle DbgDeclareInst,
DbgValueInst and DbgLoc attached to instructions. processModule will go
through all DICompileUnits in llvm.dbg.cu and list debug info MDNodes
used by the CUs.
TODO:
1> Finder has a list of CUs, SPs, Types, Scopes and global variables. We
need to add a list of variables that are used by DbgDeclareInst and
DbgValueInst.
2> MDString fields should be null or isa<MDString> and MDNode fields should be
null or isa<MDNode>. We currently use empty string or int 0 to represent null.
3> Go though Verify functions and make sure that they check field types.
4> Clean up existing testing cases to remove llvm.dbg.sp and make sure each
testing case has a llvm.dbg.cu.
llvm-svn: 187609
MDNodes used by DbgDeclareInst and DbgValueInst.
Another 16 testing cases failed and they are disabled with
-disable-debug-info-verifier.
A total of 34 cases are disabled with -disable-debug-info-verifier and will be
corrected.
llvm-svn: 186902
Simplify DIxxx:Verify to not call Verify on an operand. Instead, we use
DebugInfoFinder to list all MDNodes that should be a DIScope and all MDNodes
that should be a DIType and we will call Verify on those lists.
llvm-svn: 186737
We were incorrectly using compiler_used instead of compiler.used. Unfortunately
the passes using the broken name had tests also using the broken name.
llvm-svn: 186705
1> Use DebugInfoFinder to find debug info MDNodes.
2> Add disable-debug-info-verifier to disable verifying debug info.
3> Disable verifying for testing cases that fail (will update the testing cases
later on).
4> MDNodes generated by clang can have empty filename for TAG_inheritance and
TAG_friend, so DIType::Verify is modified accordingly.
Note that DebugInfoFinder does not list all debug info MDNode.
For example, clang can generate:
metadata !{i32 786468}, which will fail to verify.
This MDNode is used by debug info but not included in DebugInfoFinder.
This MDNode is generated as a temporary node in DIBuilder::createFunction
Value *TElts[] = { GetTagConstant(VMContext, DW_TAG_base_type) };
MDNode::getTemporary(VMContext, TElts)
llvm-svn: 186634
Add missing parenthesis such that all and not only the very first attribute
is checked.
Testing this piece of code is not possible with an LLVM-IR test file, as the
LLVM-IR parser has a similar check such that the wrong IR does not even arrive
at the verifier.
llvm-svn: 185408
The Builtin attribute is an attribute that can be placed on function call site that signal that even though a function is declared as being a builtin,
rdar://problem/13727199
llvm-svn: 185049
The effect of llvm.used is to introduce an invisible reference, so this seems
a reasonable restriction. It will be used to provide an easy ordering of
the entries in llvm.used.
llvm-svn: 183743
Other than recognizing the attribute, the patch does little else.
It changes the branch probability analyzer so that edges into
blocks postdominated by a cold function are given low weight.
Added analysis and code generation tests. Added documentation for the
new attribute.
llvm-svn: 182638
1) Disallow 'returned' on parameter that is also 'sret' (no sensible semantics, as far as I can tell).
2) Conservatively disallow tail calls through 'returned' parameters that also are 'zext' or 'sext' (for consistency with treatment of other zero-extending and sign-extending operations in tail call position detection...can be revised later to handle situations that can be determined to be safe).
This is a new attribute that is not yet used, so there is no impact.
llvm-svn: 180118
1. Verify::VerifyParameterAttrs in "lib/IR/Verifier.cpp" and
AttrBuilder::removeFunctionOnlyAttrs in "lib/IR/Attributes.cpp" (only called
by Verify::VerifyFunctionAttrs) separately maintained a list of function-only
attribute types. I've consolidated the logic into a new function used for
both cases in "lib/IR/Verifier.cpp", so this logic is in one place (other
than the AsmParser front-end)
2. Various functions in "lib/IR/Verifier.cpp" passed AttributeSet around by
reference needlessly, as it's just a handle to an immutable pimpl body.
Patch by Stephen Lin!
llvm-svn: 179790
These are two related changes (one in llvm, one in clang).
LLVM:
- rename address_safety => sanitize_address (the enum value is the same, so we preserve binary compatibility with old bitcode)
- rename thread_safety => sanitize_thread
- rename no_uninitialized_checks -> sanitize_memory
CLANG:
- add __attribute__((no_sanitize_address)) as a synonym for __attribute__((no_address_safety_analysis))
- add __attribute__((no_sanitize_thread))
- add __attribute__((no_sanitize_memory))
for S in address thread memory
If -fsanitize=S is present and __attribute__((no_sanitize_S)) is not
set llvm attribute sanitize_S
llvm-svn: 176075
The 'nobuiltin' attribute is applied to call sites to indicate that LLVM should
not treat the callee function as a built-in function. I.e., it shouldn't try to
replace that function with different code.
llvm-svn: 175835
The AttrBuilder is there to build up multiple attributes. The Attribute class
represents only one attribute at a time. So remove this unnecessary builder
creator method.
llvm-svn: 174010
The 'getSlot' function and its ilk allow introspection into the AttributeSet
class. However, that class should be opaque. Allow access through accessor
methods instead.
llvm-svn: 173522
Because the Attribute class is going to stop representing a collection of
attributes, limit the use of it as an aggregate in favor of using AttributeSet.
This replaces some of the uses for querying the function attributes.
llvm-svn: 172844
Reid Kleckner