Commit Graph

250 Commits

Author SHA1 Message Date
Rafael Espindola 3dcdb8d285 Convert test to use an extra Input file. NFC.
llvm-svn: 223414
2014-12-04 23:31:21 +00:00
Rafael Espindola 31ad468d03 Split the set of identified struct types into opaque and non-opaque ones.
The non-opaque part can be structurally uniqued. To keep this to just
a hash lookup, we don't try to unique cyclic types.

Also change the type mapping algorithm to be optimistic about a type
not being recursive and only create a new type when proven to be wrong.
This is not as strong as trying to speculate that we can keep the source
type, but is simpler (no speculation to revert) and more powerfull
than what we had before (we don't copy non-recursive types at least).

I initially wrote this to try to replace the name based type merging.
It is not strong enough to replace it, but is is a useful addition.

With this patch the number of named struct types is a clang lto bootstrap goes
from 49674 to 15986.

llvm-svn: 223278
2014-12-03 22:36:37 +00:00
Rafael Espindola 2fa1e43a22 Ask the module for its the identified types.
When lazy reading a module, the types used in a function will not be visible to
a TypeFinder until the body is read.

This patch fixes that by asking the module for its identified struct types.
If a materializer is present, the module asks it. If not, it uses a TypeFinder.

This fixes pr21374.

I will be the first to say that this is ugly, but it was the best I could find.

Some of the options I looked at:

* Asking the LLVMContext. This could be made to work for gold, but not currently
  for ld64. ld64 will load multiple modules into a single context before merging
  them. This causes us to see types from future merges. Unfortunately,
  MappedTypes is not just a cache when it comes to opaque types. Once the
  mapping has been made, we have to remember it for as long as the key may
  be used. This would mean moving MappedTypes to the Linker class and having
  to drop the Linker::LinkModules static methods, which are visible from C.

* Adding an option to ignore function bodies in the TypeFinder. This would
  fix the PR by picking the worst result. It would work, but unfortunately
  we are currently quite dependent on the upfront type merging. I will
  try to reduce our dependency, but it is not clear that we will be able
  to get rid of it for now.

The only clean solution I could think of is making the Module own the types.
This would have other advantages, but it is a much bigger change. I will
propose it, but it is nice to have this fixed while that is discussed.

With the gold plugin, this patch takes the number of types in the LTO clang
binary from 52817 to 49669.

llvm-svn: 223215
2014-12-03 07:18:23 +00:00
Peter Collingbourne 51d2de7b9e Prologue support
Patch by Ben Gamari!

This redefines the `prefix` attribute introduced previously and
introduces a `prologue` attribute.  There are a two primary usecases
that these attributes aim to serve,

  1. Function prologue sigils

  2. Function hot-patching: Enable the user to insert `nop` operations
     at the beginning of the function which can later be safely replaced
     with a call to some instrumentation facility

  3. Runtime metadata: Allow a compiler to insert data for use by the
     runtime during execution. GHC is one example of a compiler that
     needs this functionality for its tables-next-to-code functionality.

Previously `prefix` served cases (1) and (2) quite well by allowing the user
to introduce arbitrary data at the entrypoint but before the function
body. Case (3), however, was poorly handled by this approach as it
required that prefix data was valid executable code.

Here we redefine the notion of prefix data to instead be data which
occurs immediately before the function entrypoint (i.e. the symbol
address). Since prefix data now occurs before the function entrypoint,
there is no need for the data to be valid code.

The previous notion of prefix data now goes under the name "prologue
data" to emphasize its duality with the function epilogue.

The intention here is to handle cases (1) and (2) with prologue data and
case (3) with prefix data.

References
----------

This idea arose out of discussions[1] with Reid Kleckner in response to a
proposal to introduce the notion of symbol offsets to enable handling of
case (3).

[1] http://lists.cs.uiuc.edu/pipermail/llvmdev/2014-May/073235.html

Test Plan: testsuite

Differential Revision: http://reviews.llvm.org/D6454

llvm-svn: 223189
2014-12-03 02:08:38 +00:00
Rafael Espindola a4e85e3db0 Partial revert of r222986.
The explicit set of destination types is not fully redundant when lazy loading
since the TypeFinder will not find types used only in function bodies.

This keeps the logic to drop the name of mapped types since it still helps
with avoiding further renaming.

llvm-svn: 223043
2014-12-01 16:32:20 +00:00
Rafael Espindola 04a74af734 Change how we keep track of which types are in the dest module.
Instead of keeping an explicit set, just drop the names of types we choose
to map to some other type.

This has the advantage that the name of the unused will not cause the context
to rename types on module read.

llvm-svn: 222986
2014-12-01 04:15:59 +00:00
Rafael Espindola c59dc43eeb Add a test showing what the linker IdentifiedStructTypes is for.
Without this it could just be deleted and all tests would pass.

llvm-svn: 222985
2014-12-01 03:20:57 +00:00
Rafael Espindola a96f235c15 Add back r222727 with a fix.
The original patch would fail when:

* A dst opaque type (%A) is matched with a src type (%A).
* A src opaque (%E) type is then speculatively matched with %A and the
  speculation fails afterward.
* When rolling back the speculation we would cancel the source %A to dest
  %A mapping.

The fix is to keep an explicit list of which resolutions are speculative.

Original message:

Fix overly aggressive type merging.

If we find out that two types are *not* isomorphic, we learn nothing about
opaque sub types in both the source and destination.

llvm-svn: 222923
2014-11-28 16:41:24 +00:00
Rafael Espindola 93cd657cf0 Add a testcase reduced from clang lto bootstrap on OS X.
llvm-svn: 222921
2014-11-28 15:45:31 +00:00
Duncan P. N. Exon Smith c586eaa1f1 Revert "Fix overly aggressive type merging."
This reverts commit r222727, which causes LTO bootstrap failures.

Last passing @ r222698:
http://lab.llvm.org:8080/green/job/clang-Rlto_master_build/532/

First failing @ r222843:
http://lab.llvm.org:8080/green/job/clang-Rlto_master_build/533/

Internal bootstraps pointed at a much narrower range: r222725 is
passing, and r222731 is failing.

LTO crashes while handling libclang.dylib:
http://lab.llvm.org:8080/green/job/clang-Rlto_master_build/533/consoleFull#-158682280549ba4694-19c4-4d7e-bec5-911270d8a58c

    GEP is not of right type for indices!
      %InfoObj.i.i = getelementptr inbounds %"class.llvm::OnDiskIterableChainedHashTable"* %.lcssa, i64 0, i32 0, i32 4, !dbg !123627
     %"class.clang::serialization::reader::ASTIdentifierLookupTrait" = type { %"class.clang::ASTReader.31859"*, %"class.clang::serialization::ModuleFile.31870"*, %"class.clang::IdentifierInfo"* }LLVM ERROR: Broken function found, compilation aborted!
    clang: error: linker command failed with exit code 1 (use -v to see invocation)

Looks like the new algorithm doesn't merge types aggressively enough.

llvm-svn: 222895
2014-11-27 17:01:10 +00:00
Rafael Espindola c81c3f554c Set the body of a new struct as soon as it is created.
This changes the order in which different types are passed to get, but
one order is not inherently better than the other.

The main motivation is that this simplifies linkDefinedTypeBodies now that
it is only linking "real" opaque types. It is also means that we only have to
call it once and that we don't need getImpl.

A small change in behavior is that we don't copy type names when resolving
opaque types. This is an improvement IMHO, but it can be added back if
desired. A test is included with the new behavior.

llvm-svn: 222764
2014-11-25 15:33:40 +00:00
Rafael Espindola 86911440c2 Fix overly aggressive type merging.
If we find out that two types are *not* isomorphic, we learn nothing about
opaque sub types in both the source and destination.

llvm-svn: 222727
2014-11-25 05:59:24 +00:00
Rafael Espindola e96d7eb8bd Link the type of aliases.
They are not more or less "well typed" than GlobalVariables.

llvm-svn: 222725
2014-11-25 04:43:59 +00:00
Rafael Espindola 27ce577356 Add an interesting test that we already get right. NFC.
llvm-svn: 222720
2014-11-25 03:47:57 +00:00
Rafael Espindola 3410466495 Pass the .ll files to llvm-link directly. NFC.
llvm-svn: 222681
2014-11-24 20:35:59 +00:00
Duncan P. N. Exon Smith f39c3b8108 IR: Simplify uniquing for MDNode
Change uniquing from a `FoldingSet` to a `DenseSet` with custom
`DenseMapInfo`.  Unfortunately, this doesn't save any memory, since
`DenseSet<T>` is a simple wrapper for `DenseMap<T, char>`, but I'll come
back to fix that later.

I used the name `GenericDenseMapInfo` to the custom `DenseMapInfo` since
I'll be splitting `MDNode` into two classes soon: `MDNodeFwdDecl` for
temporaries, and `GenericMDNode` for everything else.

I also added a non-debug-info reduced version of a type-uniquing test
that started failing on an earlier draft of this patch.

Part of PR21532.

llvm-svn: 222191
2014-11-17 23:28:21 +00:00
Rafael Espindola 75b809c9b6 Copy externally_initialized in GlobalVariable::copyAttributesFrom.
Patch by Kevin Frei!

llvm-svn: 221620
2014-11-10 18:41:59 +00:00
Justin Hibbits 771c132e0f Add Position-independent Code model Module API.
Summary:
This makes PIC levels a Module flag attribute, which can be queried by the
backend.  The flag is named `PIC Level`, and can have a value of:

  0 - Backend-default
  1 - Small-model (-fpic)
  2 - Large-model (-fPIC)

These match the `-pic-level' command line argument for clang, and the value of the
preprocessor macro `__PIC__'.

Test Plan:
New flags tests specific for the 'PIC Level' module flag.
Tests to be added as part of a future commit for PowerPC, which will use this new API.

Reviewers: rafael, echristo

Reviewed By: rafael, echristo

Subscribers: rafael, llvm-commits

Differential Revision: http://reviews.llvm.org/D5882

llvm-svn: 221510
2014-11-07 04:46:10 +00:00
Sean Silva e727f57d37 [Linker] Add some test coverage for llvm.ident merging
llvm-svn: 221403
2014-11-05 21:33:34 +00:00
Rafael Espindola 778fcc770b Revert r221096 bringing back r221014 with a fix.
The issue was that linkAppendingVarProto does the full linking job, including
deleting the old dst variable. The fix is just to call it and return early
if we have a GV with appending linkage.

original message:

    Refactor duplicated code in liking GlobalValues.

    There is quiet a bit of logic that is common to any GlobalValue but was
    duplicated for Functions, GlobalVariables and GlobalAliases.

    While at it, merge visibility even when comdats are used, fixing pr21415.

llvm-svn: 221098
2014-11-02 13:28:57 +00:00
Chandler Carruth fd38af2d13 Revert r221014: "Refactor duplicated code in liking GlobalValues."
This commit introduces heap-use-after-free detected by ASan. Here is the output
for one of several tests that detect it:

******************** TEST 'LLVM :: Linker/AppendingLinkage.ll' FAILED ********************
Command Output (stderr):
--
=================================================================
==2122==ERROR: AddressSanitizer: heap-use-after-free on address 0x60c00000b9c8 at pc 0x0000005d05d1 bp 0x7fff64ed27c0 sp 0x7fff64ed27b8
READ of size 4 at 0x60c00000b9c8 thread T0
    #0 0x5d05d0 in llvm::GlobalValue::setUnnamedAddr(bool) /usr/local/google/home/chandlerc/src/llvm/build/../include/llvm/IR/GlobalValue.h:115:35
    #1 0x69fff1 in (anonymous namespace)::ModuleLinker::linkGlobalValueProto(llvm::GlobalValue*) /usr/local/google/home/chandlerc/src/llvm/build/../lib/Linker/LinkModules.cpp:1041:5
    #2 0x697229 in (anonymous namespace)::ModuleLinker::run() /usr/local/google/home/chandlerc/src/llvm/build/../lib/Linker/LinkModules.cpp:1485:9
    #3 0x696542 in llvm::Linker::linkInModule(llvm::Module*) /usr/local/google/home/chandlerc/src/llvm/build/../lib/Linker/LinkModules.cpp:1621:10
    #4 0x4a2db7 in main /usr/local/google/home/chandlerc/src/llvm/build/../tools/llvm-link/llvm-link.cpp:116:9
    #5 0x7f4ae61e5ec4 in __libc_start_main /build/buildd/eglibc-2.19/csu/libc-start.c:287
    #6 0x41eb71 in _start (/usr/local/google/home/chandlerc/src/llvm/build/bin/llvm-link+0x41eb71)

0x60c00000b9c8 is located 72 bytes inside of 128-byte region [0x60c00000b980,0x60c00000ba00)
freed by thread T0 here:
    #0 0x4a1e6b in operator delete(void*) /usr/local/google/home/chandlerc/src/llvm/opt-build/../projects/compiler-rt/lib/asan/asan_new_delete.cc:94:3
    #1 0x5d1a7a in llvm::iplist<llvm::GlobalVariable, llvm::ilist_traits<llvm::GlobalVariable> >::erase(llvm::ilist_iterator<llvm::GlobalVariable>) /usr/local/google/home/chandlerc/src/llvm/build/../inclu
de/llvm/ADT/ilist.h:466:5
    #2 0x5d1980 in llvm::GlobalVariable::eraseFromParent() /usr/local/google/home/chandlerc/src/llvm/build/../lib/IR/Globals.cpp:204:3
    #3 0x6a8a4d in (anonymous namespace)::ModuleLinker::linkAppendingVarProto(llvm::GlobalVariable*, llvm::GlobalVariable const*) /usr/local/google/home/chandlerc/src/llvm/build/../lib/Linker/LinkModules.
cpp:980:3
    #4 0x6a7403 in (anonymous namespace)::ModuleLinker::linkGlobalVariableProto(llvm::GlobalVariable const*, llvm::GlobalValue*, bool) /usr/local/google/home/chandlerc/src/llvm/build/../lib/Linker/LinkMod
ules.cpp:1074:11
    #5 0x69ff4e in (anonymous namespace)::ModuleLinker::linkGlobalValueProto(llvm::GlobalValue*) /usr/local/google/home/chandlerc/src/llvm/build/../lib/Linker/LinkModules.cpp:1028:13
    #6 0x697229 in (anonymous namespace)::ModuleLinker::run() /usr/local/google/home/chandlerc/src/llvm/build/../lib/Linker/LinkModules.cpp:1485:9
    #7 0x696542 in llvm::Linker::linkInModule(llvm::Module*) /usr/local/google/home/chandlerc/src/llvm/build/../lib/Linker/LinkModules.cpp:1621:10
    #8 0x4a2db7 in main /usr/local/google/home/chandlerc/src/llvm/build/../tools/llvm-link/llvm-link.cpp:116:9
    #9 0x7f4ae61e5ec4 in __libc_start_main /build/buildd/eglibc-2.19/csu/libc-start.c:287

previously allocated by thread T0 here:
    #0 0x4a192b in operator new(unsigned long) /usr/local/google/home/chandlerc/src/llvm/opt-build/../projects/compiler-rt/lib/asan/asan_new_delete.cc:62:35
    #1 0x61d85c in llvm::User::operator new(unsigned long, unsigned int) /usr/local/google/home/chandlerc/src/llvm/build/../lib/IR/User.cpp:57:19
    #2 0x6a7525 in (anonymous namespace)::ModuleLinker::linkGlobalVariableProto(llvm::GlobalVariable const*, llvm::GlobalValue*, bool) /usr/local/google/home/chandlerc/src/llvm/build/../lib/Linker/LinkMod
ules.cpp:1100:3
    #3 0x69ff4e in (anonymous namespace)::ModuleLinker::linkGlobalValueProto(llvm::GlobalValue*) /usr/local/google/home/chandlerc/src/llvm/build/../lib/Linker/LinkModules.cpp:1028:13
    #4 0x697229 in (anonymous namespace)::ModuleLinker::run() /usr/local/google/home/chandlerc/src/llvm/build/../lib/Linker/LinkModules.cpp:1485:9
    #5 0x696542 in llvm::Linker::linkInModule(llvm::Module*) /usr/local/google/home/chandlerc/src/llvm/build/../lib/Linker/LinkModules.cpp:1621:10
    #6 0x4a2db7 in main /usr/local/google/home/chandlerc/src/llvm/build/../tools/llvm-link/llvm-link.cpp:116:9
    #7 0x7f4ae61e5ec4 in __libc_start_main /build/buildd/eglibc-2.19/csu/libc-start.c:287

SUMMARY: AddressSanitizer: heap-use-after-free /usr/local/google/home/chandlerc/src/llvm/build/../include/llvm/IR/GlobalValue.h:115 llvm::GlobalValue::setUnnamedAddr(bool)
Shadow bytes around the buggy address:
  0x0c187fff96e0: fa fa fa fa fa fa fa fa 00 00 00 00 00 00 00 00
  0x0c187fff96f0: 00 00 00 00 00 00 00 fa fa fa fa fa fa fa fa fa
  0x0c187fff9700: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fa
  0x0c187fff9710: fa fa fa fa fa fa fa fa 00 00 00 00 00 00 00 00
  0x0c187fff9720: 00 00 00 00 00 00 00 00 fa fa fa fa fa fa fa fa
=>0x0c187fff9730: fd fd fd fd fd fd fd fd fd[fd]fd fd fd fd fd fd
  0x0c187fff9740: fa fa fa fa fa fa fa fa fd fd fd fd fd fd fd fd
  0x0c187fff9750: fd fd fd fd fd fd fd fa fa fa fa fa fa fa fa fa
  0x0c187fff9760: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
  0x0c187fff9770: fa fa fa fa fa fa fa fa fd fd fd fd fd fd fd fd
  0x0c187fff9780: fd fd fd fd fd fd fd fd fa fa fa fa fa fa fa fa
Shadow byte legend (one shadow byte represents 8 application bytes):
  Addressable:           00
  Partially addressable: 01 02 03 04 05 06 07
  Heap left redzone:       fa
  Heap right redzone:      fb
  Freed heap region:       fd
  Stack left redzone:      f1
  Stack mid redzone:       f2
  Stack right redzone:     f3
  Stack partial redzone:   f4
  Stack after return:      f5
  Stack use after scope:   f8
  Global redzone:          f9
  Global init order:       f6
  Poisoned by user:        f7
  Container overflow:      fc
  Array cookie:            ac
  ASan internal:           fe
==2122==ABORTING

llvm-svn: 221096
2014-11-02 09:10:31 +00:00
Rafael Espindola 4e27567a12 Refactor duplicated code in liking GlobalValues.
There is quiet a bit of logic that is common to any GlobalValue but was
duplicated for Functions, GlobalVariables and GlobalAliases.

While at it, merge visibility even when comdats are used, fixing pr21415.

llvm-svn: 221014
2014-10-31 23:10:07 +00:00
Rafael Espindola 67926f10e8 Unify and update link-messages.ll and redefinition.ll. NFC.
llvm-svn: 220968
2014-10-31 16:52:30 +00:00
Rafael Espindola 5b24759dff Move an input file to Inputs instead of using RUN: true.
llvm-svn: 220953
2014-10-31 05:54:15 +00:00
Rafael Espindola e5204efeaf merge tests for constant linking.
llvm-svn: 220951
2014-10-31 05:04:16 +00:00
Rafael Espindola d1e64b1e93 Fix the merging of the constantness of declarations.
The langref says:

LLVM explicitly allows declarations of global variables to be marked
constant, even if the final definition of the global is not. This
capability can be used to enable slightly better optimization of the
program, but requires the language definition to guarantee that
optimizations based on the ‘constantness’ are valid for the
translation units that do not include the definition.

Given that definition, when merging two declarations, we have to drop
constantness if of of them is not marked contant, since the Module
without the constant marker might not have the necessary guarantees.

llvm-svn: 220927
2014-10-30 20:50:23 +00:00
Rafael Espindola f9a94abd4e Update test to pass .ll to llvm-link and use Inputs.
llvm-svn: 220924
2014-10-30 20:23:59 +00:00
Rafael Espindola 6e0b559d4f Add a test for the -suppress-warnings option.
llvm-svn: 220603
2014-10-25 01:14:15 +00:00
Rafael Espindola 52b249b9f4 Cleanup this test a bit.
Use simpler names and remove unnecessary fields.

llvm-svn: 220499
2014-10-23 19:36:21 +00:00
Rafael Espindola 2c301f5c8c Cleanup this test a bit.
Use simpler names and remove unnecessary fields.

llvm-svn: 220498
2014-10-23 19:23:42 +00:00
Rafael Espindola 28d6b27bba Make this test a bit stricter.
This now:
* Forces the linker to include the internal definition.
* Checks the full output.

llvm-svn: 220495
2014-10-23 18:52:46 +00:00
Rafael Espindola c16ec3ed42 Make this test a bit stricter.
This now:
* Forces the linker to include the internal definition.
* Checks the full output.

llvm-svn: 220494
2014-10-23 18:44:07 +00:00
Frederic Riss d1cfc3c791 [dwarfdump] Print the name for referenced specification of abstract_origin DIEs.
Reviewers: dblaikie, samsonov, echristo, aprantl

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D5466

llvm-svn: 219099
2014-10-06 03:36:31 +00:00
Duncan P. N. Exon Smith 176b691d32 Revert "Revert "DI: Fold constant arguments into a single MDString""
This reverts commit r218918, effectively reapplying r218914 after fixing
an Ocaml bindings test and an Asan crash.  The root cause of the latter
was a tightened-up check in `DILexicalBlock::Verify()`, so I'll file a
PR to investigate who requires the loose check (and why).

Original commit message follows.

--

This patch addresses the first stage of PR17891 by folding constant
arguments together into a single MDString.  Integers are stringified and
a `\0` character is used as a separator.

Part of PR17891.

Note: I've attached my testcases upgrade scripts to the PR.  If I've
just broken your out-of-tree testcases, they might help.

llvm-svn: 219010
2014-10-03 20:01:09 +00:00
Duncan P. N. Exon Smith 786cd049fc Revert "DI: Fold constant arguments into a single MDString"
This reverts commit r218914 while I investigate some bots.

llvm-svn: 218918
2014-10-02 22:15:31 +00:00
Duncan P. N. Exon Smith 571f97bd90 DI: Fold constant arguments into a single MDString
This patch addresses the first stage of PR17891 by folding constant
arguments together into a single MDString.  Integers are stringified and
a `\0` character is used as a separator.

Part of PR17891.

Note: I've attached my testcases upgrade scripts to the PR.  If I've
just broken your out-of-tree testcases, they might help.

llvm-svn: 218914
2014-10-02 21:56:57 +00:00
Adrian Prantl 87b7eb9d0f Move the complex address expression out of DIVariable and into an extra
argument of the llvm.dbg.declare/llvm.dbg.value intrinsics.

Previously, DIVariable was a variable-length field that has an optional
reference to a Metadata array consisting of a variable number of
complex address expressions. In the case of OpPiece expressions this is
wasting a lot of storage in IR, because when an aggregate type is, e.g.,
SROA'd into all of its n individual members, the IR will contain n copies
of the DIVariable, all alike, only differing in the complex address
reference at the end.

By making the complex address into an extra argument of the
dbg.value/dbg.declare intrinsics, all of the pieces can reference the
same variable and the complex address expressions can be uniqued across
the CU, too.
Down the road, this will allow us to move other flags, such as
"indirection" out of the DIVariable, too.

The new intrinsics look like this:
declare void @llvm.dbg.declare(metadata %storage, metadata %var, metadata %expr)
declare void @llvm.dbg.value(metadata %storage, i64 %offset, metadata %var, metadata %expr)

This patch adds a new LLVM-local tag to DIExpressions, so we can detect
and pretty-print DIExpression metadata nodes.

What this patch doesn't do:

This patch does not touch the "Indirect" field in DIVariable; but moving
that into the expression would be a natural next step.

http://reviews.llvm.org/D4919
rdar://problem/17994491

Thanks to dblaikie and dexonsmith for reviewing this patch!

Note: I accidentally committed a bogus older version of this patch previously.
llvm-svn: 218787
2014-10-01 18:55:02 +00:00
Adrian Prantl b458dc2eee Revert r218778 while investigating buldbot breakage.
"Move the complex address expression out of DIVariable and into an extra"

llvm-svn: 218782
2014-10-01 18:10:54 +00:00
Adrian Prantl 25a7174e7a Move the complex address expression out of DIVariable and into an extra
argument of the llvm.dbg.declare/llvm.dbg.value intrinsics.

Previously, DIVariable was a variable-length field that has an optional
reference to a Metadata array consisting of a variable number of
complex address expressions. In the case of OpPiece expressions this is
wasting a lot of storage in IR, because when an aggregate type is, e.g.,
SROA'd into all of its n individual members, the IR will contain n copies
of the DIVariable, all alike, only differing in the complex address
reference at the end.

By making the complex address into an extra argument of the
dbg.value/dbg.declare intrinsics, all of the pieces can reference the
same variable and the complex address expressions can be uniqued across
the CU, too.
Down the road, this will allow us to move other flags, such as
"indirection" out of the DIVariable, too.

The new intrinsics look like this:
declare void @llvm.dbg.declare(metadata %storage, metadata %var, metadata %expr)
declare void @llvm.dbg.value(metadata %storage, i64 %offset, metadata %var, metadata %expr)

This patch adds a new LLVM-local tag to DIExpressions, so we can detect
and pretty-print DIExpression metadata nodes.

What this patch doesn't do:

This patch does not touch the "Indirect" field in DIVariable; but moving
that into the expression would be a natural next step.

http://reviews.llvm.org/D4919
rdar://problem/17994491

Thanks to dblaikie and dexonsmith for reviewing this patch!

llvm-svn: 218778
2014-10-01 17:55:39 +00:00
Rafael Espindola fe3842cda7 Merge alignment of common GlobalValue.
Fixes pr20882.

llvm-svn: 217455
2014-09-09 17:48:18 +00:00
Rafael Espindola 0910605af6 When merging two common GlobalValues, keep the largest.
llvm-svn: 217451
2014-09-09 15:59:12 +00:00
Rafael Espindola 14a41ce802 Make this input file pass the verifier.
This was not noticed before because llvm-link only runs the verifier on the
result and these globals were not present in the result.

llvm-svn: 217450
2014-09-09 15:40:12 +00:00
Rafael Espindola c83c8d4e74 Fix a use of an undefined value (the linkage).
llvm-svn: 217445
2014-09-09 14:52:27 +00:00
Rafael Espindola 7fc29546f9 Prefer common over weak linkage when linking.
This matches the behavior of ELF linkers.

llvm-svn: 217443
2014-09-09 14:27:09 +00:00
Rafael Espindola d31dc048ca Fix pr20078.
When linking llvm.global_ctors with the optional third element we have to handle
it specially and only copy the elements whose keys were also copied.

llvm-svn: 217281
2014-09-05 21:27:52 +00:00
Frederic Riss 878065bb21 [ dwarfdump ] Add symbolic dump of known DWARF attribute values.
Reviewed By: dblaikie

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D5187

llvm-svn: 217186
2014-09-04 19:39:20 +00:00
Adrian Prantl daedfda892 Debug info: Add a new explicit DIDescriptor flag for the "public" access
specifier and change the default behavior to only emit the
DW_AT_accessibility(public) attribute when the isPublic() is explicitly
set.

rdar://problem/18154959

llvm-svn: 216799
2014-08-29 22:44:07 +00:00
David Blaikie b3833ef0c1 Fix a couple of debug info test cases to match the metadata schema change in r216239
Found these while testing something else.

llvm-svn: 216505
2014-08-27 00:04:16 +00:00
Rafael Espindola 3931c28b03 Set comdats when lazily linking functions.
We were setting the comdat when functions were copied in the initial pass, but
not when they were linked only when we found out that they are needed.

llvm-svn: 215765
2014-08-15 20:17:08 +00:00
Duncan P. N. Exon Smith 09d84addb7 Don't upgrade global constructors when reading bitcode
An optional third field was added to `llvm.global_ctors` (and
`llvm.global_dtors`) in r209015.  Most of the code has been changed to
deal with both versions of the variables.  Users of the C API might
create either version, the helper functions in LLVM create the two-field
version, and clang now creates the three-field version.

However, the BitcodeReader was changed to always upgrade to the
three-field version.  This created an unnecessary inconsistency in the
IR before/after serializing to bitcode.

This commit resolves the inconsistency by making the third field truly
optional (and not upgrading in the bitcode reader).  Since `llvm-link`
was relying on this upgrade code, rather than deleting it I've moved it
into `ModuleLinker`, where it upgrades these arrays as necessary to
resolve inconsistencies between modules.

The ideal resolution would be to remove the 2-field version and make the
third field required.  I filed PR20506 to track that.

I changed `test/Bitcode/upgrade-global-ctors.ll` to a negative test and
duplicated the `llvm-link` check in `test/Linker/global_ctors.ll` to
check both upgrade directions.

Since I came across this as part of PR5680 (serializing use-list order),
I've also added the missing `verify-uselistorder` RUN line to
`test/Bitcode/metadata-2.ll`.

llvm-svn: 215457
2014-08-12 16:46:37 +00:00
Rafael Espindola b16196a3e0 Fix use of uninitialized variable.
Fixes linking bitcode files that use the new style comdats for constructors
with ones that don't.

llvm-svn: 215364
2014-08-11 17:07:34 +00:00
Rafael Espindola 464fe024c5 Use "weak alias" instead of "alias weak"
Before this patch we had

@a = weak global ...
but
@b = alias weak ...

The patch changes aliases to look more like global variables.

Looking at some really old code suggests that the reason was that the old
bison based parser had a reduction for alias linkages and another one for
global variable linkages. Putting the alias first avoided the reduce/reduce
conflict.

The days of the old .ll parser are long gone. The new one parses just "linkage"
and a later check is responsible for deciding if a linkage is valid in a
given context.

llvm-svn: 214355
2014-07-30 22:51:54 +00:00
Manman Ren 4dbffad804 Clean up testing cases.
llvm-svn: 214142
2014-07-28 23:16:05 +00:00
Manman Ren bd3c17cc86 Remove extra ; in testing case.
llvm-svn: 214137
2014-07-28 22:46:46 +00:00
Manman Ren f8a1967c8c [Debug Info] add DISubroutineType and its creation takes DITypeArray.
DITypeArray is an array of DITypeRef, at its creation, we will create
DITypeRef (i.e use the identifier if the type node has an identifier).

This is the last patch to unique the type array of a subroutine type.

rdar://17628609

llvm-svn: 214132
2014-07-28 22:24:06 +00:00
David Majnemer dad0a645a7 IR: Add COMDATs to the IR
This new IR facility allows us to represent the object-file semantic of
a COMDAT group.

COMDATs allow us to tie together sections and make the inclusion of one
dependent on another. This is required to implement features like MS
ABI VFTables and optimizing away certain kinds of initialization in C++.

This functionality is only representable in COFF and ELF, Mach-O has no
similar mechanism.

Differential Revision: http://reviews.llvm.org/D4178

llvm-svn: 211920
2014-06-27 18:19:56 +00:00
Rafael Espindola 42a4c9f9e0 Allow aliases to be unnamed_addr.
Alias with unnamed_addr were in a strange state. It is stored in GlobalValue,
the language reference talks about "unnamed_addr aliases" but the verifier
was rejecting them.

It seems natural to allow unnamed_addr in aliases:

* It is a property of how it is accessed, not of the data itself.
* It is perfectly possible to write code that depends on the address
of an alias.

This patch then makes unname_addr legal for aliases. One side effect is that
the syntax changes for a corner case: In globals, unnamed_addr is now printed
before the address space.

llvm-svn: 210302
2014-06-06 01:20:28 +00:00
Rafael Espindola 64c1e18033 Allow alias to point to an arbitrary ConstantExpr.
This  patch changes GlobalAlias to point to an arbitrary ConstantExpr and it is
up to MC (or the system assembler) to decide if that expression is valid or not.

This reduces our ability to diagnose invalid uses and how early we can spot
them, but it also lets us do things like

@test5 = alias inttoptr(i32 sub (i32 ptrtoint (i32* @test2 to i32),
                                 i32 ptrtoint (i32* @bar to i32)) to i32*)

An important implication of this patch is that the notion of aliased global
doesn't exist any more. The alias has to encode the information needed to
access it in its metadata (linkage, visibility, type, etc).

Another consequence to notice is that getSection has to return a "const char *".
It could return a NullTerminatedStringRef if there was such a thing, but when
that was proposed the decision was to just uses "const char*" for that.

llvm-svn: 210062
2014-06-03 02:41:57 +00:00
David Blaikie 3c2fff3fe6 DebugInfo: Lazily construct subprogram definition DIEs.
A further step to correctly emitting concrete out of line definitions
preceeding inlined instances of the same program.

To do this, emission of subprograms must be delayed until required since
we don't know which (abstract only (if there's no out of line
definition), concrete only (if there are no inlined instances), or both)
DIEs are required at the start of the module.

To reduce the test churn in the following commit that actually fixes the
bug, this commit introduces the lazy DIE construction and cleans up test
cases that are impacted by the changes in the resulting DIE ordering.

llvm-svn: 209675
2014-05-27 18:37:48 +00:00
David Blaikie 2f75351c02 DebugInfo: Generalize some tests to handle variations in attribute ordering.
In an effort to fix inlined debug info in situations where the out of
line definition of a function preceeds any inlined usage, the order in
which some attributes are added to subprogram DIEs may change. (in
essence, definition-necessary attributes like DW_AT_low_pc/high_pc will
be added immediately, but the names, types, and other features will be
delayed to module end where they may either be added to the subprogram
DIE or instead reference an abstract definition for those values)

These tests can be generalized to be resilient to this change. 5 or so
tests actually have to be incompatibly changed to cope with this
reordering and will go along with the change that affects the order.

llvm-svn: 209554
2014-05-23 21:11:46 +00:00
Adrian Prantl eb1ddfc8f4 LTO: Add a testcase for linking modules with incompatible Debug Info
Versions.
rdar://problem/16926122

llvm-svn: 209183
2014-05-19 23:41:25 +00:00
Reid Kleckner fceb76f5f9 Add comdat key field to llvm.global_ctors and llvm.global_dtors
This allows us to put dynamic initializers for weak data into the same
comdat group as the data being initialized.  This is necessary for MSVC
ABI compatibility.  Once we have comdats for guard variables, we can use
the combination to help GlobalOpt fire more often for weak data with
guarded initialization on other platforms.

Reviewers: nlewycky

Differential Revision: http://reviews.llvm.org/D3499

llvm-svn: 209015
2014-05-16 20:39:27 +00:00
Rafael Espindola 6b238633b7 Fix most of PR10367.
This patch changes the design of GlobalAlias so that it doesn't take a
ConstantExpr anymore. It now points directly to a GlobalObject, but its type is
independent of the aliasee type.

To avoid changing all alias related tests in this patches, I kept the common
syntax

@foo = alias i32* @bar

to mean the same as now. The cases that used to use cast now use the more
general syntax

@foo = alias i16, i32* @bar.

Note that GlobalAlias now behaves a bit more like GlobalVariable. We
know that its type is always a pointer, so we omit the '*'.

For the bitcode, a nice surprise is that we were writing both identical types
already, so the format change is minimal. Auto upgrade is handled by looking
through the casts and no new fields are needed for now. New bitcode will
simply have different types for Alias and Aliasee.

One last interesting point in the patch is that replaceAllUsesWith becomes
smart enough to avoid putting a ConstantExpr in the aliasee. This seems better
than checking and updating every caller.

A followup patch will delete getAliasedGlobal now that it is redundant. Another
patch will add support for an explicit offset.

llvm-svn: 209007
2014-05-16 19:35:39 +00:00
Rafael Espindola 89992b0d6b Fix DataLayout::operator==().
Patch by Maks Naumov!

llvm-svn: 206911
2014-04-22 17:47:03 +00:00
Adrian Prantl 1a1647cab6 Switch the type field in DIVariable and DIGlobalVariable over to DITypeRefs.
This allows us to catch more opportunities for ODR-based type uniquing
during LTO.
Paired commit with CFE which updates some testcases to verify the new
DIBuilder behavior.

llvm-svn: 204106
2014-03-18 02:34:58 +00:00
Adrian Prantl 2e4e62e2cc Debug info: Unique types before emitting them to DWARF, where applicable.
llvm-svn: 203983
2014-03-14 23:08:29 +00:00
Adrian Prantl d1e6a4e189 Debug Info: Fix LTO type uniquing for C++ member declarations
based on the ODR.

This adds an OdrMemberMap to DwarfDebug which is used to unique C++
member function declarations based on the unique identifier of their
containing class and their mangled name.
We can't use the usual DIRef mechanism here because DIScopes are indexed
using their entire MDNode, including decl_file and decl_line, which need
not be unique (see testcase).

Prior to this change multiple redundant member function declarations would
end up in the same uniqued DW_TAG_class_type.

llvm-svn: 203982
2014-03-14 23:08:25 +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 698a5bdbba Don't assume an empty stderr.
GuardMalloc can print info to stderr, causing these tests to fail.
Since FileCheck errors on empty inputs, just add a bit of dummy
data to make it happy.

llvm-svn: 203595
2014-03-11 18:25:33 +00:00
JF Bastien 76086c667d Add test for LinkModules warning on triple, modified by r203009. Datalayout is already tested.
llvm-svn: 203468
2014-03-10 15:54:49 +00:00
JF Bastien d44807ca67 Fix datalayout test that I broke with my previous LinkModules warning improvement.
llvm-svn: 203011
2014-03-05 21:37:08 +00:00
Juergen Ributzka 95d11dee8b Revert "Use count 0."
This reverts commit r202283, because when we use GuardMalloc the test will fail
due to additional output to std err.

llvm-svn: 202341
2014-02-27 03:10:10 +00:00
Rafael Espindola b556fcbdb5 Use count 0.
Thanks to Roman Divacky for the suggestion.

llvm-svn: 202283
2014-02-26 17:57:35 +00:00
Rafael Espindola ae593f1563 Compare DataLayout by Value, not by pointer.
This fixes spurious warnings in llvm-link about the datalayout not matching.

Thanks to Zalman Stern for reporting the bug!

llvm-svn: 202276
2014-02-26 17:02:08 +00:00
Rafael Espindola 75ec01f3de Copy dll storage in copyAttributes.
llvm-svn: 201295
2014-02-13 05:11:35 +00:00
David Blaikie 5e390e4df7 DebugInfo: Remove some unneeded conditionals now that DIBuilder no longer emits zero-length arrays as {i32 0}
A bunch of test cases needed to be cleaned up for this, many my fault -
when implementid imported modules I updated test cases by simply
duplicating the prior metadata field - which wasn't always the empty
metadata entry.

llvm-svn: 200731
2014-02-04 01:23:52 +00:00
Timur Iskhodzhanov f166f6c8d0 Reland r200340 - 'Add line table debug info to COFF files when using a win32 triple'
This incorporates a couple of fixes reviewed at http://llvm-reviews.chandlerc.com/D2651

llvm-svn: 200440
2014-01-30 01:39:17 +00:00
Bill Wendling 3c68b0d484 Verify that attributes are not lost during linking.
We don't want to lose attributes when a function decl without them is merged
with a function decl that has them.
PR2382

llvm-svn: 200030
2014-01-24 19:20:15 +00:00
Adrian Prantl ef129fbb41 Debug info (LTO): Move the creation of accessibility flags to
getOrCreateSubprogramDIE to avoid attributes being added twice when DIEs
are merged.

rdar://problem/15842330.

llvm-svn: 199536
2014-01-18 02:12:00 +00:00
Manman Ren 409558f81e Debug Info: update testing cases to specify the debug info version number.
We are going to drop debug info without a version number or with a different
version number, to make sure we don't crash when we see bitcode files with
different debug info metadata format.

llvm-svn: 195504
2013-11-22 21:49:45 +00:00
Manman Ren 4dbdc9021d Debug Info: remove duplication of DIEs when a DIE can be shared across CUs.
We add a map in DwarfDebug to map MDNodes that are shareable across CUs to the
corresponding DIEs: MDTypeNodeToDieMap. These DIEs can be shared across CUs,
that is why we keep the maps in DwarfDebug instead of CompileUnit.

We make the assumption that if a DIE is not added to an owner yet, we assume
it belongs to the current CU. Since DIEs for the type system are added to
their owners immediately after creation, and other DIEs belong to the current
CU, the assumption should be true.

A testing case is added to show that we only create a single DIE for a type
MDNode and we use ref_addr to refer to the type DIE.

We also add a testing case to show ref_addr relocations for non-darwin
platforms.

llvm-svn: 193779
2013-10-31 17:54:35 +00:00
Manman Ren b3388601fb Debug Info: In DIBuilder, the derived-from field of a DW_TAG_pointer_type
is updated to use DITypeRef.

Move isUnsignedDIType and getOriginalTypeSize from DebugInfo.h to be static
helper functions in DwarfCompileUnit. We already have a static helper function
"isTypeSigned" in DwarfCompileUnit, and a pointer to DwarfDebug is added to
resolve the derived-from field. All three functions need to go across link
for derived-from fields, so we need to get hold of a type identifier map.

A pointer to DwarfDebug is also added to DbgVariable in order to resolve the
derived-from field.

Debug info verifier is updated to check a derived-from field is a TypeRef.
Verifier will not go across link for derived-from fields, in debug info finder,
we go across the link to add derived-from fields to types.

Function getDICompositeType is only used by dragonegg and since dragonegg does
not generate identifier for types, we use an empty map to resolve the
derived-from field.

When printing a derived-from field, we use DITypeRef::getName to either return
the type identifier or getName of the DIType.

A paired commit at clang is required due to changes to DIBuilder.

llvm-svn: 192018
2013-10-05 01:43:03 +00:00
Eric Christopher e595bae4a4 Temporarily revert r191792 as it is causing some LTO debug failures
on platforms with relocations in debug info and also temporarily
revert r191800 due to conflicts with the revert of r191792.

llvm-svn: 191967
2013-10-04 17:08:38 +00:00
Manman Ren 9a0a67035e Debug Info: In DIBuilder, the derived-from field of a DW_TAG_pointer_type
is updated to use DITypeRef.

Move isUnsignedDIType and getOriginalTypeSize from DebugInfo.h to be static
helper functions in DwarfCompileUnit. We already have a static helper function
"isTypeSigned" in DwarfCompileUnit, and a pointer to DwarfDebug is added to
resolve the derived-from field. All three functions need to go across link
for derived-from fields, so we need to get hold of a type identifier map.

A pointer to DwarfDebug is also added to DbgVariable in order to resolve the
derived-from field.

Debug info verifier is updated to check a derived-from field is a TypeRef.
Verifier will not go across link for derived-from fields, in debug info finder,
we go across the link to add derived-from fields to types.

Function getDICompositeType is only used by dragonegg and since dragonegg does
not generate identifier for types, we use an empty map to resolve the
derived-from field.

When printing a derived-from field, we use DITypeRef::getName to either return
the type identifier or getName of the DIType.

A paired commit at clang is required due to changes to DIBuilder.

llvm-svn: 191800
2013-10-01 23:45:54 +00:00
Manman Ren 79b887f3e3 Remove triple from type unique testing cases.
llvm-svn: 191794
2013-10-01 20:27:56 +00:00
Manman Ren 512dc5660a Try to fix native-arm bot
llvm-svn: 191793
2013-10-01 20:23:12 +00:00
Manman Ren 8990d7ee84 Debug Info: remove duplication of DIEs when a DIE is part of the type system
and it is shared across CUs.

We add a few maps in DwarfDebug to map MDNodes for the type system to the
corresponding DIEs: MDTypeNodeToDieMap, MDSPNodeToDieMap, and
MDStaticMemberNodeToDieMap. These DIEs can be shared across CUs, that is why we
keep the maps in DwarfDebug instead of CompileUnit.

Sometimes, when we try to add an attribute to a DIE, the DIE is not yet added
to its owner yet, so we don't know whether we should use ref_addr or ref4.
We create a worklist that will be processed during finalization to add
attributes with the correct form (ref_addr or ref4).

We add addDIEEntry to DwarfDebug to be a wrapper around DIE->addValue. It checks
whether we know the correct form, if not, we update the worklist
(DIEEntryWorklist).

A testing case is added to show that we only create a single DIE for a type
MDNode and we use ref_addr to refer to the type DIE.

llvm-svn: 191792
2013-10-01 19:52:23 +00:00
Peter Collingbourne 3fa50f9b05 Implement function prefix data as an IR feature.
Previous discussion:
http://lists.cs.uiuc.edu/pipermail/llvmdev/2013-July/063909.html

Differential Revision: http://llvm-reviews.chandlerc.com/D1191

llvm-svn: 190773
2013-09-16 01:08:15 +00:00
Manman Ren 15b2abf229 Debug Info: In DIBuilder, the context fields of a TAG_inheritance and a
TAG_friend are updated to use scope reference.

Added testing cases to verify that class with inheritance can be uniqued.

llvm-svn: 190364
2013-09-09 23:07:58 +00:00
Manman Ren 122792dc4d Debug Info Testing: remove a commented out line.
llvm-svn: 190351
2013-09-09 20:45:34 +00:00
Manman Ren 116868eadd Debug Info: Use DIScopeRef for DIType::getContext.
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
2013-09-09 19:47:11 +00:00
Manman Ren f2a88f3622 Debug Info Testing: update context from empty string to null.
Context should be either null or MDNode.

llvm-svn: 190267
2013-09-08 03:11:54 +00:00
Manman Ren deeafd8a58 Debug Info Testing: updated to use NULL instead of "i32 0" in a few fields.
Field 2 of DIType (Context), field 9 of DIDerivedType (TypeDerivedFrom),
field 12 of DICompositeType (ContainingType), fields 2, 7, 12 of DISubprogram
(Context, Type, ContainingType).

llvm-svn: 190205
2013-09-06 21:03:58 +00:00
Rafael Espindola fac3a018d1 Error on linking appending globals with different unnamed_addr.
llvm-svn: 189950
2013-09-04 15:33:34 +00:00
Rafael Espindola fd9a9415f5 Fix linking of unnamed_addr in functions.
llvm-svn: 189945
2013-09-04 14:59:03 +00:00
Rafael Espindola df814e976d Rename in preparation for adding tests for function linking.
llvm-svn: 189944
2013-09-04 14:40:49 +00:00
Rafael Espindola 3a3563d4be Use CHECK-DAG instead of sort.
llvm-svn: 189942
2013-09-04 14:35:48 +00:00
Rafael Espindola d4885daefa Fix linking of unnamed_addr.
This was regression from r134829. When linking we have to be conservative. If
one of the symbols has a significant address, then the result should have it
too.

llvm-svn: 189935
2013-09-04 14:05:09 +00:00
Daniel Dunbar 5c8f5c1c26 [tests] Use multiple statements instead of 'echo -e', which is not part of BSD echo.
llvm-svn: 189560
2013-08-29 03:02:30 +00:00
Manman Ren 0ed70aeb85 Debug Info: add an identifier field to DICompositeType.
DICompositeType will have an identifier field at position 14. For now, the
field is set to null in DIBuilder.
For DICompositeTypes where the template argument field (the 13th field)
was optional, modify DIBuilder to make sure the template argument field is set.
Now DICompositeType has 15 fields.

Update DIBuilder to use NULL instead of "i32 0" for null value of a MDNode.
Update verifier to check that DICompositeType has 15 fields and the last
field is null or a MDString.

Update testing cases to include an extra field for DICompositeType.
The identifier field will be used by type uniquing so a front end can
genearte a DICompositeType with a unique identifer.

llvm-svn: 189282
2013-08-26 22:39:55 +00:00