Commit Graph

102 Commits

Author SHA1 Message Date
Reid Kleckner 5772b77789 Add 'musttail' marker to call instructions
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
2014-04-24 20:14:34 +00:00
Duncan P. N. Exon Smith 0d640014ff verify-di: Add back braces for MSVC compatability
Fixup after r206300.

<rdar://problem/15500563>

llvm-svn: 206305
2014-04-15 17:28:26 +00:00
Duncan P. N. Exon Smith 6ef5f284d6 verify-di: Implement DebugInfoVerifier
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
2014-04-15 16:27:38 +00:00
Duncan P. N. Exon Smith 67b44da0dd verify-di: split out VerifierSupport
Split out assertion and output helpers from Verifier in preparation for
writing the DebugInfoVerifier.

<rdar://problem/15500563>

llvm-svn: 206299
2014-04-15 16:27:32 +00:00
Craig Topper c620761ca5 [C++11] More 'nullptr' conversion or in some cases just using a boolean check instead of comparing to nullptr.
llvm-svn: 205831
2014-04-09 06:08:46 +00:00
Duncan P. N. Exon Smith 2541d4e525 Verifier: Give the right message for bad atomic loads
Talk about load (not store) on an invalid atomic load.

<rdar://problem/16287567>

llvm-svn: 205777
2014-04-08 17:07:44 +00:00
Eric Christopher 484182779d Invert the option to enable debug info verification. No functional
change outside of the command line to enable it.

llvm-svn: 205713
2014-04-07 13:55:21 +00:00
Tim Northover 4516de3412 Intrinsics: add LLVMHalfElementsVectorType constraint
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
2014-03-29 07:04:54 +00:00
Tim Northover aa3cf1e691 Intrinsics: expand semantics of LLVMExtendedVectorType (& trunc)
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
2014-03-28 12:31:39 +00:00
Rafael Espindola 24a669d225 Prevent alias from pointing to weak aliases.
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
2014-03-27 15:26:56 +00:00
Rafael Espindola 65481d7b97 Revert "Prevent alias from pointing to weak aliases."
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
2014-03-26 06:14:40 +00:00
Rafael Espindola 3b712a84a9 Prevent alias from pointing to weak aliases.
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
2014-03-26 04:48:47 +00:00
Alon Mishne ad312155a6 [C++11] Change DebugInfoFinder to use range-based loops
Also changes the iterators to return actual DI type over MDNode.

llvm-svn: 204130
2014-03-18 09:41:07 +00:00
Rafael Espindola f3336bc1d5 Reject alias to undefined symbols in the verifier.
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
2014-03-12 20:15:49 +00:00
Rafael Espindola 2e43aff460 Avoid repeated calls to CE->getOperand(0). No functionality change.
llvm-svn: 203686
2014-03-12 18:08:14 +00:00
Tim Northover e94a518a22 IR: add a second ordering operand to cmpxhg for failure
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
2014-03-11 10:48:52 +00:00
Justin Bogner 28e1cf6061 IR: Slightly more verbose error in Verifier
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
2014-03-10 21:22:44 +00:00
Ahmed Charles 821b66669c [C++11] Fix break due to MSVC bug.
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
2014-03-09 04:57:09 +00:00
Chandler Carruth cdf4788401 [C++11] Add range based accessors for the Use-Def chain of a Value.
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
2014-03-09 03:16:01 +00:00
Chandler Carruth 7da14f1ab9 [Layering] Move InstVisitor.h into the IR library as it is pretty
obviously coupled to the IR.

llvm-svn: 203064
2014-03-06 03:23:41 +00:00
Chandler Carruth 9a4c9e597b [Layering] Move DebugInfo.h into the IR library where its implementation
already lives.

llvm-svn: 203046
2014-03-06 00:46:21 +00:00
Craig Topper f398d7c6bf [C++11] Add 'override' keyword to IR library.
llvm-svn: 202939
2014-03-05 06:35:38 +00:00
Chandler Carruth 8cd041ef19 [Modules] Move the ConstantRange class into the IR library. This is
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
2014-03-04 12:24:34 +00:00
Chandler Carruth 1305dc3351 [Modules] Move CFG.h to the IR library as it defines graph traits over
IR types.

llvm-svn: 202827
2014-03-04 11:45:46 +00:00
Chandler Carruth 219b89b987 [Modules] Move CallSite into the IR library where it belogs. It is
abstracting between a CallInst and an InvokeInst, both of which are IR
concepts.

llvm-svn: 202816
2014-03-04 11:01:28 +00:00
Rafael Espindola 79c3ab7c5e Check that GlobalAliases don't have section or alignment.
An alias is always in the section of its aliasee and has the same alignment
(since it has the same address).

llvm-svn: 201354
2014-02-13 18:26:41 +00:00
Chandler Carruth 4d35631a6c [PM] Wire up the Verifier for the new pass manager and connect it to the
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
2014-01-20 11:34:08 +00:00
Chandler Carruth 043949d446 [PM] Make the verifier work independently of any pass manager.
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
2014-01-19 02:22:18 +00:00
Chandler Carruth bf2b652c05 [PM] [cleanup] Rename some of the Verifier's members, re-arrange them,
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
2014-01-17 11:09:34 +00:00
Chandler Carruth 7677760ec8 [PM] Remove the preverifier and directly compute the DominatorTree for
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
2014-01-17 10:56:02 +00:00
Reid Kleckner 60d3a835ff Change inalloca rules to make it only apply to the last parameter
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
2014-01-16 22:59:24 +00:00
Nico Rieck 7157bb765e Decouple dllexport/dllimport from linkage
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
2014-01-14 15:22:47 +00:00
Nico Rieck 9d2e0df049 Revert "Decouple dllexport/dllimport from linkage"
Revert this for now until I fix an issue in Clang with it.

This reverts commit r199204.

llvm-svn: 199207
2014-01-14 12:38:32 +00:00
Nico Rieck e43aaf7967 Decouple dllexport/dllimport from linkage
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
2014-01-14 11:55:03 +00:00
Chandler Carruth 73523021d0 [PM] Split DominatorTree into a concrete analysis result object which
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
2014-01-13 13:07:17 +00:00
Chandler Carruth 5ad5f15cff [cleanup] Move the Dominators.h and Verifier.h headers into the IR
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
2014-01-13 09:26:24 +00:00
Chandler Carruth d48cdbf0c3 Put the functionality for printing a value to a raw_ostream as an
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
2014-01-09 02:29:41 +00:00
Chandler Carruth 9aca918df9 Move the LLVM IR asm writer header files into the IR directory, as they
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
2014-01-07 12:34:26 +00:00
Matt Arsenault 00436ea156 Allow addrspacecast in global aliases
llvm-svn: 198349
2014-01-02 20:55:01 +00:00
Reid Kleckner a534a38130 Begin adding docs and IR-level support for the inalloca attribute
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
2013-12-19 02:14:12 +00:00
Kaelyn Uhrain 4e8656077c Fix the segfault reported in PR 11990.
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
2013-12-07 00:13:34 +00:00
Paul Robinson dcbe35bad5 The 'optnone' attribute means don't inline anything into this function
(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
2013-11-18 21:44:03 +00:00
Manman Ren 101d345227 Debug Info Verifier: disable it by default.
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
2013-11-18 03:19:31 +00:00
Manman Ren c9e395e9ac Debug Info Verifier: fix when to find debug info nodes and when to verify them.
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
2013-11-17 18:48:57 +00:00
Manman Ren 2085cccf99 Debug Info Verifier: enable public functions of Finder to update the type map.
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
2013-11-17 18:42:37 +00:00
Manman Ren 23662907fc Debug Info Verifier: remove un-used argument in verifyDebugInfo.
No functionality change.

llvm-svn: 194917
2013-11-16 02:34:57 +00:00
Matt Arsenault b03bd4d96b Add addrspacecast instruction.
Patch by Michele Scandale!

llvm-svn: 194760
2013-11-15 01:34:59 +00:00
Rafael Espindola 156227ac2b Don't call doFinalization from verifyFunction.
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
2013-11-13 13:44:11 +00:00
Rafael Espindola 716e7405d3 Remove linkonce_odr_auto_hide.
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
2013-11-01 17:09:14 +00:00
Andrew Trick a2efd99bdf Enable variable arguments support for intrinsics.
llvm-svn: 193766
2013-10-31 17:18:11 +00:00